| a high-resolution reference map for cytoplasmic and membrane-associated proteins of corynebacterium glutamicum. | we present a high-resolution reference map for soluble proteins obtained from corynebacterium glutamicum cells grown in glucose minimal medium. the analysis window covers the pl range from 4-6 and the molecular mass range from 5-100 kda. using overlapping narrow immobilized ph gradients for isoelectric focusing, 970 protein spots were detected after second-dimensional separation on sds-polyacrylamide gels and colloidal coomassie-staining. by tryptic peptide mass fingerprinting 169 protein spots ... | 2001 | 11824608 |
| expression of genes of lipid synthesis and altered lipid composition modulates l-glutamate efflux of corynebacterium glutamicum. | l-glutamate is made with corynebacterium glutamicum on a scale of more than 106 tons/year. nevertheless, formation of this amino acid is enigmatic and there is very limited molecular information available to unravel the apparently complex conditions leading to l-glutamate efflux. here, we report the isolation and overexpression of the genes involved in lipid synthesis: acp, fadd 15, cma, cls, pgsa2, cdsa, gpsa, and plsc, and the inactivation of cma and cls. in addition, the consequences for phos ... | 2002 | 11831479 |
| corynebacterium glutamicum utilizes both transsulfuration and direct sulfhydrylation pathways for methionine biosynthesis. | a direct sulfhydrylation pathway for methionine biosynthesis in corynebacterium glutamicum was found. the pathway was catalyzed by mety encoding o-acetylhomoserine sulfhydrylase. the gene mety, located immediately upstream of meta, was found to encode a protein of 437 amino acids with a deduced molecular mass of 46,751 da. in accordance with dna and protein sequence data, the introduction of mety into c. glutamicum resulted in the accumulation of a 47-kda protein in the cells and a 30-fold incre ... | 2002 | 11844756 |
| a novel methodology employing corynebacterium glutamicum genome information to generate a new l-lysine-producing mutant. | classical whole-cell mutagenesis has achieved great success in development of many industrial fermentation strains, but has the serious disadvantage of accumulation of uncharacterized secondary mutations that are detrimental to their performance. in the post-genomic era, a novel methodology which avoids this drawback presents itself. this "genome-based strain reconstruction" involves identifying mutations by comparative genomic analysis, defining mutations beneficial for production, and assembli ... | 2002 | 11876415 |
| strategy to sequence the genome of corynebacterium glutamicum atcc 13032: use of a cosmid and a bacterial artificial chromosome library. | the initial strategy of the corynebacterium glutamicum genome project was to sequence overlapping inserts of an ordered cosmid library. high-density colony grids of approximately 28 genome equivalents were used for the identification of overlapping clones by southern hybridization. altogether 18 contiguous genomic segments comprising 95 overlapping cosmids were assembled. systematic shotgun sequencing of the assembled cosmid set revealed that only 2.84 mb (86.6%) of the c. glutamicum genome were ... | 2002 | 11879709 |
| sensing nitrogen limitation in corynebacterium glutamicum: the role of glnk and glnd. | a novel nitrogen control system regulating the transcription of genes expressed in response to nitrogen starvation in corynebacterium glutamicum was identified by us recently. in this communication, we also show that the nitrogen regulation cascade in c. glutamicum functions by a new mechanism, although components highly similar to sensor and signal transmitter proteins of escherichia coli are used, namely uridylyltransferase and a pii-type glnk protein. the genes encoding these key components o ... | 2001 | 11886559 |
| osmosensing and osmoregulatory compatible solute accumulation by bacteria. | bacteria inhabit natural and artificial environments with diverse and fluctuating osmolalities, salinities and temperatures. many maintain cytoplasmic hydration, growth and survival most effectively by accumulating kosmotropic organic solutes (compatible solutes) when medium osmolality is high or temperature is low (above freezing). they release these solutes into their environment when the medium osmolality drops. solutes accumulate either by synthesis or by transport from the extracellular med ... | 2001 | 11913457 |
| l-methionine degradation potentialities of cheese-ripening microorganisms. | volatile sulphur compounds are major flavouring compounds in many traditional fermented foods including cheeses. these compounds are products of the catabolism of l-methionine by cheese-ripening microorganisms. the diversity of l-methionine degradation by such microorganisms, however, remains to be characterized. the objective of this work was to compare the capacities to produce volatile sulphur compounds by five yeasts, geotrichum candidum, yarrowia lipolytica, kluyveromyces lactis, debaryomyc ... | 2001 | 11928962 |
| bacterial amino acid transport proteins: occurrence, functions, and significance for biotechnological applications. | transport processes play a pivotal role in cellular metabolism, e.g. for the uptake of nutrients or the excretion of metabolic waste products. moreover, they are also important in biotechnological processes such as the production of various amino acids by the use of microorganisms. the focus of this review is on bacterial amino acid transport systems, in particular those of corynebacterium glutamicum and escherichia coli, with respect to their function and biotechnological significance. | 2002 | 11935175 |
| [serological affinity of some species of nonpathogenic corynebacteria]. | serological peculiarities of the species strains corynebacterium glutamicum, c. ammoniagenes, c. vitaeruminis, c. variabilis and strain of corynebacterium sp. (brevibacterium stationis) ucm ac-719 have been investigated with the help of immunoenzyme analysis elisa with the use of mice immune serum, specific to c. ammoniagenes ucm ac-732t, c. vitaeruminis ucm ac-718t, c. variabilis ucm ac-717t, c. glutamicum ucm ac-733 and corynebacterium sp. ucm ac-719. it has been established that the species o ... | 2002 | 11944349 |
| nitrogen assimilation in corynebacterium diphtheriae: pathways and regulatory cascades. | genes encoding proteins for ammonium uptake, assimilation, and the nitrogen regulatory system in corynebacterium diphtheriae were studied on basis of homology searches using corynebacterium glutamicum genes as query sequences. regulation of transcription of these genes in response to nitrogen starvation was analyzed by rna hybridization experiments and knock-out mutants were generated to verify the function of distinct genes. in this communication, we were able to identify the key components of ... | 2002 | 11959451 |
| linking central metabolism with increased pathway flux: l-valine accumulation by corynebacterium glutamicum. | mutants of corynebacterium glutamicum were made and enzymatically characterized to clone ilvd and ilve, which encode dihydroxy acid dehydratase and transaminase b, respectively. these genes of the branched-chain amino acid synthesis were overexpressed together with ilvbn (which encodes acetohydroxy acid synthase) and ilvc (which encodes isomeroreductase) in the wild type, which does not excrete l-valine, to result in an accumulation of this amino acid to a concentration of 42 mm. since l-valine ... | 2002 | 11976094 |
| identification of two prpdbc gene clusters in corynebacterium glutamicum and their involvement in propionate degradation via the 2-methylcitrate cycle. | genome sequencing revealed that the corynebacterium glutamicum genome contained, besides glta, two additional citrate synthase homologous genes (prpc) located in two different prpdbc gene clusters, which were designated prpd1b1c1 and prpd2b2c2. the coding regions of the two gene clusters as well as the predicted gene products showed sequence identities of about 70 to 80%. significant sequence similarities were found also to the prpbcde operons of escherichia coli and salmonella enterica, which a ... | 2002 | 11976302 |
| intraspecific diversity of brevibacterium linens, corynebacterium glutamicum and rhodococcus erythropolis based on partial 16s rdna sequence analysis and fourier-transform infrared (ft-ir) spectroscopy. | the intraspecific diversity of 31 strains of brevibacterium linens, 27 strains of corynebacterium glutamicum and 29 strains of rhodococcus erythropolis was determined by partial 16s rdna sequence analysis and fourier-transform infrared (ft-ir) spectroscopy. as a prerequisite for the analyses, 27 strains derived from culture collections which had carried invalid or wrong species designations were reclassified in accordance with polyphasic taxonomical data. ft-ir spectroscopy proved to be a rapid ... | 2002 | 11988527 |
| charting and unzipping the surface layer of corynebacterium glutamicum with the atomic force microscope. | bacterial surface layers (s-layers) are extracellular protein networks that act as molecular sieves and protect a large variety of archaea and bacteria from hostile environments. atomic force microscopy (afm) was used to asses the s-layer of coryne-bacterium glutamicum formed of ps2 proteins that assemble into hexameric complexes within a hexagonal lattice. native and trypsin-treated s-layers were studied. using the afm stylus as a nanodissector, native arrays that adsorbed to mica as double lay ... | 2002 | 11994150 |
| evidence for a partial redundancy of the fibronectin-binding proteins for the transfer of mycoloyl residues onto the cell wall arabinogalactan termini of mycobacterium tuberculosis. | mycobacterium tuberculosis produces a series of major secreted proteins, the fibronectin-binding proteins (fbps), also known as the antigen 85 complex, that are believed to play an essential role in the pathogenesis of tuberculosis through their mycoloyltransferase activity required for maintaining the integrity of the bacterial cell envelope. four different fbp genes are found in the genome of m. tuberculosis, but the reason for the existence of these fbps sharing the same substrate specificity ... | 2002 | 12010501 |
| flexibility of the metabolism of corynebacterium glutamicum 2262, a glutamic acid-producing bacterium, in response to temperature upshocks. | in order to test the temperature sensitivity of glutamate production metabolism, several temperature shifts, from 33 to 37, 38, 39, 40 or 41 degrees c, were applied to the temperature-sensitive strain, corynebacterium glutamicum 2262, cultivated in a 24-h fed-batch process. whereas glucose was entirely dedicated to biomass synthesis when cells were grown at 33 degrees c, applying temperature upshocks, whatever their range, triggered a redistribution of the carbon utilisation between glutamate, b ... | 2002 | 12032806 |
| influence of glucose, fructose and sucrose as carbon sources on kinetics and stoichiometry of lysine production by corynebacterium glutamicum. | batch cultivations of l-lysine-producing corynebacterium glutamicum atcc 21253 were carried out on the different carbon sources, glucose, sucrose and fructose. the time profiles of substrate and product concentrations were evaluated to compare kinetics and stoichiometry of lysine production. the lysine yield (mol c/mol c) on glucose was 8% higher than on sucrose and 30% higher than on fructose. the highest final biomass concentration of 5.0 g/l was obtained on glucose, whereas fructose and sucro ... | 2002 | 12032807 |
| augmentation of nkt and nk cell-mediated cytotoxicity by peptidoglycan monomer linked with zinc. | peptidoglycan monomer (pgm), which was originally prepared by biosynthesis from culture fluids of penicillin-treated brevibacterium divaricatum, is an immunostimulator, the activities of which might be improved by addition of zinc (zn) to the basic molecule. | 2002 | 12061425 |
| export of l-isoleucine from corynebacterium glutamicum: a two-gene-encoded member of a new translocator family. | bacteria possess amino acid export systems, and corynebacterium glutamicum excretes l-isoleucine in a process dependent on the proton motive force. in order to identify the system responsible for l-isoleucine export, we have used transposon mutagenesis to isolate mutants of c. glutamicum sensitive to the peptide isoleucyl-isoleucine. in one such mutant, strong peptide sensitivity resulted from insertion into a gene designated brnf encoding a hydrophobic protein predicted to possess seven transme ... | 2002 | 12081967 |
| l-glutamic acid production in a continuous stirred tank bioreactor using coimmobilized bio-catalyst using a fluorosensor. | the production of l-glutamic acid has been studied using coimmobilized whole cells of pseudomonas reptilivora and micrococcus glutamicus in a two litre tokyo rikakikai fermentor using glucose as selected production medium. the process was carried out at an optimum temperature of 32 degree celsius and a ph of 7.2. the progress of the reaction was recorded using dr. ingold fluorosensor. the effect of initial substrate concentration, speed of agitation, volume ofcalcium alginate beads and aeration ... | 2002 | 12085657 |
| identification of glya (encoding serine hydroxymethyltransferase) and its use together with the exporter thre to increase l-threonine accumulation by corynebacterium glutamicum. | l-threonine can be made by the amino acid-producing bacterium corynebacterium glutamicum. however, in the course of this process, some of the l-threonine is degraded to glycine. we detected an aldole cleavage activity of l-threonine in crude extracts with an activity of 2.2 nmol min(-1) (mg of protein)(-1). in order to discover the molecular reason for this activity, we cloned glya, encoding serine hydroxymethyltransferase (shmt). by using affinity-tagged glya, shmt was isolated and its substrat ... | 2002 | 12089010 |
| influence of threonine exporters on threonine production in escherichia coli. | threonine production in escherichia coli threonine producer strains is enhanced by overexpression of the e. coli rhtb and rhtc genes or by heterologous overexpression of the gene encoding the corynebacterium glutamicum threonine excretion carrier, thre. both e. coli genes give rise to a threonine-resistant phenotype when overexpressed, and they decrease the accumulation of radioactive metabolites derived from [(14)c] l-threonine. the evidence presented supports the conclusion that both rhtb and ... | 2002 | 12111147 |
| genome-wide transcription profiling of corynebacterium glutamicum after heat shock and during growth on acetate and glucose. | to monitor the global gene expression of corynebacterium glutamicum we established two formats of dna-arrays on nylon membranes. we produced an ordered dna-array of pcr fragments from a shotgun library of c. glutamicum representing a threefold coverage of the genome. with this format we studied genome-wide transcriptional changes after heat shock. sequence and subsequent blast analysis of pcr fragments with elevated expression after heat shock revealed pcr fragments harboring genes that encode s ... | 2002 | 12141991 |
| corynebacterium efficiens sp. nov., a glutamic-acid-producing species from soil and vegetables. | three glutamic-acid-producing coryneform strains were isolated from soil and vegetable samples. chemotaxonomic investigations indicated that these strains belonged to the genus corynebacterium. phylogenetic studies, based on 16s rdna analysis, demonstrated that the three strains formed a distinct cluster within the genus corynebacterium and that their nearest relatives were corynebacterium glutamicum and corynebacterium callunae, also known as glutamic-acid-producing species. the data from 16s r ... | 2002 | 12148616 |
| transcriptome analysis of acetate metabolism in corynebacterium glutamicum using a newly developed metabolic array. | following the determination of the whole-genome sequence of corynebacterium glutamicum, we have developed a dna array to extensively investigate gene expression and regulation relevant to carbon metabolism. for this purpose, a total of 120 c. glutamicum genes, including those in central metabolism and amino acid biosyntheses, were amplified by pcr and printed onto glass slides. the resulting array, designated a "metabolic array", was used for hybridization with fluorescently labeled cdna probes ... | 2002 | 12162556 |
| plasmid-borne macrolide resistance in micrococcus luteus. | a plasmid designated pmec2 which confers resistance to erythromycin, other macrolides, and lincomycin was detected in micrococcus luteus strain maw843 isolated from human skin. curing of this approximately 4.2 kb plasmid from the host organism resulted in erythromycin sensitivity of the strain. introduction of pmec2 into a different m. luteus strain conferred erythromycin resistance upon this strain. macrolide resistance in m. luteus maw843 was an inducible trait. induction occurred at subinhibi ... | 2002 | 12177341 |
| antibacterial activity in four marine crustacean decapods. | a search for antibacterial activity in different body-parts of pandalus borealis (northern shrimp), pagurus bernhardus (hermit crab), hyas araneus (spider crab) and paralithodes camtschatica (king crab) was conducted. dried samples were extracted with 60% (v/v) acetonitrile, containing 0.1% (v/v) trifluoroacetic acid, and further extracted and concentrated on c18 cartridges. eluates from the solid phase extraction were tested for antibacterial, lysozyme and haemolytic activity. antibacterial act ... | 2002 | 12194450 |
| the alanine racemase gene alr is an alternative to antibiotic resistance genes in cloning systems for industrial corynebacterium glutamicum strains. | the potential of the alanine racemase gene alr from corynebacterium glutamicum atcc 13032 to substitute for antibiotic resistance determinants in cloning systems has been investigated. the alr gene was identified by a pcr technique and its nucleotide sequence was determined. the deduced protein revealed the highest amino acid sequence similarity to the alr protein from mycobacterium smegmatis with 45% identical and 58% similar amino acids. a defined alr deletion mutant of c. glutamicum displayed ... | 2002 | 12204559 |
| optimisation of a culture medium containing fish silage for l-lysine production by corynebacterium glutamicum. | in a first step the effects of 10 components of a culture medium designed for l-lysine production were evaluated with a 2(10-6) factorial design. among them, glucose, fish silage, and ammonium sulphate showed a significant effect. in a second step, an orthogonal-central composite experimental design and response surface methodology was performed with five from the 10 initial compounds. the determination coefficient (r2) of the fitted second-order model was 0.990. l-lysine production with the opt ... | 2002 | 12227548 |
| efficient electrotransformation of corynebacterium diphtheriae with a mini-replicon derived from the corynebacterium glutamicum plasmid pga1. | efficient transformation of the human pathogen corynebacterium diphtheriae was achieved with novel cloning vectors consisting of a mini-replicon from the cryptic c. glutamicum plasmid pga1 as well as of the aph(3')-iia or teta(z ) antibiotic resistance genes. plasmid-containing transformants of c. diphtheriae were recovered at frequencies ranging from 1.3 x 10(5) to 4.8 x 10(6) colony forming units (cfu)/microg of plasmid dna. vector dna was directly transferred from escherichia coli into c. dip ... | 2002 | 12232668 |
| carbon flux analysis in a pantothenate overproducing corynebacterium glutamicum strain. | carbon flux analysis during a pseudo-stationary phase of metabolite accumulation in a genetically engineered strain of corynebacterium glutamicum, containing plasmids leading to over-expression of the ilvbncd and panbc operons, has identified the basic metabolic constraints governing the potential of this bacterium to produce pantothenate. carbon flux converging on pyruvate (75% of glucose uptake) is controlled by anabolic precursor requirements and nadph demand provoking high carbon loss as co2 ... | 2002 | 12241042 |
| influence of adjuvant-active peptidoglycan monomer on specific t cell responses in mice. | peptidoglycan monomer (pgm) originating from brevibacterium divaricatum is a non-toxic, non-pyrogenic, water-soluble immunostimulator. it potentiates humoral immune response to ovalbumin (ova) in mice upregulating both immunoglobulin (igg) 1 and igg2a antibody subclasses. this study concerns the influence of pgm on t cell activation and cytokine networks in response to ova. ova-specific proliferative response as well as interferon-gamma (ifn-gamma) and interleukin-4 (il-4) secretion in lymph nod ... | 2002 | 12297400 |
| the 27.8-kb r-plasmid ptet3 from corynebacterium glutamicum encodes the aminoglycoside adenyltransferase gene cassette aada9 and the regulated tetracycline efflux system tet 33 flanked by active copies of the widespread insertion sequence is6100. | we determined the complete nucleotide sequence of the 27.8-kb r-plasmid ptet3 from corynebacterium glutamicum lp-6 which encodes streptomycin, spectinomycin, and tetracycline resistance. the antibiotic resistance determinant of ptet3 comprises an inti1-like gene, which was truncated by the insertion sequence is6100, and the novel aminoglycoside adenyltransferase gene cassette aada9. the deduced aada9 protein showed 61% identity and 71% similarity to aada6 of integron in51 from pseudomonas aerugi ... | 2002 | 12383729 |
| effect of pyruvate carboxylase overexpression on the physiology of corynebacterium glutamicum. | pyruvate carboxylase was recently sequenced in corynebacterium glutamicum and shown to play an important role of anaplerosis in the central carbon metabolism and amino acid synthesis of these bacteria. in this study we investigate the effect of the overexpression of the gene for pyruvate carboxylase (pyc) on the physiology of c. glutamicum atcc 21253 and atcc 21799 grown on defined media with two different carbon sources, glucose and lactate. in general, the physiological effects of pyc overexpr ... | 2002 | 12406733 |
| atypical location of double-strand origin of replication (nic site) on the plasmid pga1 from corynebacterium glutamicum. | the double-strand origin of replication (dso) of the rolling-circle-replicating (rc) plasmid pga1 from corynebacterium glutamicum was analyzed using the runoff dna synthesis assay. the site- and strand-specific breakage of double-stranded plasmid dna, representing the nic site of dso, was localized precisely within the sequence 5'-ctgg decreases at-3' in the distal part of the pga1 rep gene. this location of dso differs from the dso positions found on other rc plasmids and is in agreement with t ... | 2002 | 12422507 |
| characterization of a novel plasmid pxz608 from corynebacterium glutamicum. | the complete nucleotide sequence of a novel cryptic plasmid pxz608 from corynebacterium glutamicum 227 was determined. pxz608 was 5949 bp with six open reading frames (orf1-6). the predicted orf1 gene product was homologous to replication proteins of rolling circle replication plasmids. the conserved single- and double-stranded origins of rolling circle replication were found, and interestingly, the two origins were both located on orf1, which indicated that the rep protein encoded by orf1 could ... | 2002 | 12423755 |
| s-layer protein transport across the cell wall of corynebacterium glutamicum: in vivo kinetics and energy requirements. | corynebacteria are gram-positive bacteria with a very peculiar cell envelope structure as it is constituted of an inner membrane and an outer membrane-like structure. protein secretion in corynebacterium glutamicum was studied in vivo, using the s-layer protein ps2 as a model. we show that different variants of ps2 protein are exported through the whole cell envelope with a half-life ranging between 2 and 4 min, by a two-step mechanism. the first step, which is over after about 1.5 min, is atp- ... | 2002 | 12445648 |
| purification, characterization and identification of cysteine desulfhydrase of corynebacterium glutamicum, and its relationship to cysteine production. | we highly purified the enzyme having l-cysteine desulfhydrase activity from corynebacterium glutamicum. according to its partial amino acid sequence, the enzyme was identified as the aecd gene product, a c-s lyase with alpha, beta-elimination activity [i. rossol and a. pühler (1992) j. bacteriol. 174, 2968-2977]. to produce l-cysteine in c. glutamicum, the escherichia coli-altered cyse gene encoding met256ile mutant serine acetyltransferase, which is desensitized to feedback inhibition by l-cyst ... | 2002 | 12445652 |
| purification of a cytochrome bc-aa3 supercomplex with quinol oxidase activity from corynebacterium glutamicum. identification of a fourth subunity of cytochrome aa3 oxidase and mutational analysis of diheme cytochrome c1. | the aerobic respiratory chain of the gram-positive corynebacterium glutamicum involves a bc(1) complex with a diheme cytochrome c(1) and a cytochrome aa(3) oxidase but no additional c-type cytochromes. here we show that the two enzymes form a supercomplex, because affinity chromatography of either strep-tagged cytochrome b (qcrb) or strep-tagged subunit i (ctad) of cytochrome aa(3) always resulted in the copurification of the subunits of the bc(1) complex (qcra, qcrb, qcrc) and the aa(3) complex ... | 2003 | 12446663 |
| genealogy profiling through strain improvement by using metabolic network analysis: metabolic flux genealogy of several generations of lysine-producing corynebacteria. | a comprehensive approach of metabolite balancing, (13)c tracer studies, gas chromatography-mass spectrometry, matrix-assisted laser desorption ionization-time of flight mass spectrometry, and isotopomer modeling was applied for comparative metabolic network analysis of a genealogy of five successive generations of lysine-producing corynebacterium glutamicum. the five strains examined (c. glutamicum atcc 13032, 13287, 21253, 21526, and 21543) were previously obtained by random mutagenesis and sel ... | 2002 | 12450803 |
| 3-phosphoglycerate dehydrogenase from corynebacterium glutamicum: the c-terminal domain is not essential for activity but is required for inhibition by l-serine. | the sera gene of corynebacterium glutamicum coding for 3-phosphoglycerate dehydrogenase (pgdh) was isolated and functionally characterized. it encodes a polypeptide of 530 aminoacyl residues (aa), which is substantially longer than the corresponding escherichia coli polypeptide of 410 aa. the difference is largely due to an additional stretch of aa in the carboxy- (c)-terminal part of the polypeptide. overexpression of sera in c. glutamicum results in a 16-fold increase in specific pgdh activity ... | 2002 | 12466884 |
| accumulation of anthranilic acid and n-glucosylanthranilic acid by a corynebacterium glutamicum mutant resistant to dl-serine hydroxamate. | during a study on the effect of dl-serine hydroxamate on corynebacterium glutamicum (jcm1318, a wild strain), a mutant resistant to the drug, strain to3002, was isolated. this mutant accumulated five ehrlich's reagent positive fluorescent substances in the culture medium. two major and one minor fluorescent products were isolated by preparative high-performance liquid chromatography following charcoal column chromatography from the culture supernatant. one major product was identified as anthran ... | 1999 | 12501374 |
| secretion of active-form streptoverticillium mobaraense transglutaminase by corynebacterium glutamicum: processing of the pro-transglutaminase by a cosecreted subtilisin-like protease from streptomyces albogriseolus. | the transglutaminase secreted by streptoverticillium mobaraense is a useful enzyme in the food industry. a fragment of transglutaminase was secreted by corynebacterium glutamicum when it was coupled on a plasmid to the promoter and signal peptide of a cell surface protein from c. glutamicum. we analyzed the signal peptide and the pro-domain of the transglutaminase gene and found that the signal peptide consists of 31 amino acid residues and the pro-domain consists of 45 residues. when the pro-do ... | 2003 | 12514016 |
| metabolic engineering of glutamate production. | since the discovery of corynebacterium glutamicum as an efficient glutamate-overproducing microorganism in 1957, the production of l-amino acids by the fermentative method has become one of the most important research-target of industrial microbiology. several research groups have developed metabolic engineering principles for l-amino acid-producing c. glutamicum strains over the last four decades. the mechanism of l-glutamate-overproduction by the microorganism is very unique and interesting. l ... | 2003 | 12523388 |
| biotechnological manufacture of lysine. | l-lysine has been manufactured using corynebacterium glutamicum for more than 40 years. nowadays production exceeds 600,000 tons per year. based on conventionally bred strains, further improvement of lysine productivity has been achieved by genetic engineering. pyruvate carboxylase, aspartate kinase, dihydrodipicolinate synthase, homoserine dehydrogenase and the specific lysine exporter were shown to be key enzymes for lysine production and were characterized in detail. their combined engineerin ... | 2003 | 12523389 |
| metabolic flux redistribution in corynebacterium glutamicum in response to osmotic stress. | osmotic stress constitutes a major bacterial stress factor in the soil and during industrial fermentation. in this paper, we quantified the metabolic response, in terms of metabolic flux redistribution, of a lysine-overproducing strain of corynebacterium glutamicum grown under continuous culture, to gradually increasing osmolality. oxygen and carbon dioxide evolution rates, and the changes in concentration of extracellular, as well as intracellular, metabolites were measured throughout the osmot ... | 2003 | 12536254 |
| integrated optical sensing of dissolved oxygen in microtiter plates: a novel tool for microbial cultivation. | microtiter plates with integrated optical sensing of dissolved oxygen were developed by immobilization of two fluorophores at the bottom of 96-well polystyrene microtiter plates. the oxygen-sensitive fluorophore responded to dissolved oxygen concentration, whereas the oxygen-insensitive one served as an internal reference. the sensor measured dissolved oxygen accurately in optically well-defined media. oxygen transfer coefficients, k(l)a, were determined by a dynamic method in a commercial micro ... | 2003 | 12557316 |
| [analysis on integration sites of transposon-insertion mutant by transposon rescue]. | in order to define the chromosomal locus of the transposon integration in a mutant of corynebacterium glutamicum, transposon rescue experiments were performed. by isolating parts of the transposon together with adjacent parts of the bacterial chromosome and subsequent sequencing of the adjacent parts, the mutant was found to have three transposon integrations, one just in front of the citrate synthase gene glta, the other two in hitherto unknown open reading frames designated orfa and orfb. the ... | 2002 | 12557374 |
| [site-directed construction of in-frame deletion mutants of corynebacterium glutamicum]. | this study is focused on corynebacterium glutamicum, an important producer in amino-acids industry, by the protocol with construction of the in-frame deletion fragments of targeting genes, application of dna recombination technique and so on. we achieved successfully the defined deletion mutants in frame of the single gene or double genes. the in-frame deletion mutants are subsequently analyzed and confirmed by polymerase chain reaction and sequencing. | 2002 | 12557553 |
| i do it my way: regulation of ammonium uptake and ammonium assimilation in corynebacterium glutamicum. | in order to utilize different nitrogen sources and to survive situations of nitrogen limitation, microorganisms have developed several mechanisms to adapt their metabolism to changes in the nitrogen supply. in this communication, recent advances in our knowledge of ammonium uptake, its assimilation, and connected regulatory systems in corynebacterium glutamicum are discussed with respect to the situation in the bacterial model organisms escherichia coli and bacillus subtilis. the regulatory netw ... | 2003 | 12560985 |
| molecular and biochemical characterization of mechanosensitive channels in corynebacterium glutamicum. | database searches in the corynebacterium glutamicum genome sequence revealed homologs of the mechanosensitive channels mscl and yggb of escherichia coli. to elucidate the physiological role of these putative channels deletion mutants were constructed. betaine efflux induced by osmotic downshock of the mscl deletion mutant was nearly identical to that of the wild-type, whereas the yggb deletion mutant showed a reduced efflux rate. interestingly, the double deletion strain, which was expected to h ... | 2003 | 12586408 |
| characterization of the gene encoding glutamate dehydrogenase ( gdha) from the ruminal bacterium ruminococcus flavefaciens fd-1. | the gene encoding glutamate dehydrogenase ( gdha) in the ruminal bacterium ruminococcus flavefaciens fd-1 was cloned. a degenerate primer based on the n-terminal amino acid sequence of the purified protein was used in conjunction with genome walking to obtain the complete orf of 1,365 bp, capable of encoding a polypeptide of 455 amino acid residues. the translated orf contained the amino acid motifs characteristic of the subfamily gdh s_50(i) small glutamate dehydrogenases, including the catalyt ... | 2003 | 12610723 |
| changes of pentose phosphate pathway flux in vivo in corynebacterium glutamicum during leucine-limited batch cultivation as determined from intracellular metabolite concentration measurements. | corynebacterium glutamicum is an important organism for the industrial production of amino acids such as lysine. in the present study time-dependent changes in the oxidative pentose phosphate pathway activity, an important site of nadph regeneration in c. glutamicum, are investigated, whereby intracellular metabolite concentrations and specific enzyme activities in two isogenic leucine auxotrophic strains differing only in the regulation of their aspartate kinases were compared. after leucine li ... | 2002 | 12646324 |
| disparity between changes in mrna abundance and enzyme activity in corynebacterium glutamicum: implications for dna microarray analysis. | the relationship between changes in mrna abundance and enzyme activity was determined for three genes over a span of nearly 3 h during amino acid production in corynebacterium glutamicum. gene expression changes during c. glutamicum fermentations were examined by complementary dna (cdna) microarrays and by a second method for quantitating rna levels, competitive reverse transcriptase-pcr (rt-pcr). the results obtained independently by both methods were compared and found to be in agreement, thus ... | 2003 | 12658516 |
| glts, the sodium-coupled l-glutamate uptake system of corynebacterium glutamicum: identification of the corresponding gene and impact on l-glutamate production. | a screening procedure was established to identify corynebacterium glutamicum transposon mutants with an altered l-glutamate excretion behaviour. by this microtiter plate-based approach seven non- or less excreting c. glutamicum strains and two hyper-excreters were found. the subsequently carried out molecular analysis of a hyper-producing clone led to the identification of the glts gene, which codes for the sodium-coupled secondary l-glutamate uptake system in c. glutamicum. characterization of ... | 2003 | 12664155 |
| control of rep gene expression in plasmid pga1 from corynebacterium glutamicum. | the cryptic multicopy plasmid pga1 (4,826 bp) from corynebacterium glutamicum lp-6 belongs to the fifth group of rolling-circle-replicating plasmids. a determinant, which negatively controls pga1 replication, was localized in the leader region of the rep gene coding for the initiator of plasmid replication. this region, when cloned into the compatible vector pec6, was found to cause decrease of segregational stability of the pga1 derivative pkg48. a promoter and a single transcriptional start si ... | 2003 | 12670963 |
| global expression profiling and physiological characterization of corynebacterium glutamicum grown in the presence of l-valine. | addition of l-valine (50 to 200 mm) to glucose minimal medium had no effect on the growth of wild-type corynebacterium glutamicum atcc 13032 but inhibited the growth of the derived valine production strain val1 [13032 deltailva deltapanbc(pjc1ilvbncd)] in a concentration-dependent manner. in order to explore this strain-specific valine effect, genomewide expression profiling was performed using dna microarrays, which showed that valine caused an increased ilvbn mrna level in val1 but not in the ... | 2003 | 12732517 |
| production of native-type streptoverticillium mobaraense transglutaminase in corynebacterium glutamicum. | we previously observed secretion of active-form transglutaminase in corynebacterium glutamicum by coexpressing the subtilisin-like protease sam-p45 from streptomyces albogriseolus to process the prodomain. however, the n-terminal amino acid sequence of the transglutaminase differed from that of the native streptoverticillium mobaraense enzyme. in the present work we have used site-directed mutagenesis to generate an optimal sam-p45 cleavage site in the c-terminal region of the prodomain. as a re ... | 2003 | 12732581 |
| identification and functional analysis of six mycolyltransferase genes of corynebacterium glutamicum atcc 13032: the genes cop1, cmt1, and cmt2 can replace each other in the synthesis of trehalose dicorynomycolate, a component of the mycolic acid layer of the cell envelope. | by data mining in the sequence of the corynebacterium glutamicum atcc 13032 genome, six putative mycolyltransferase genes were identified that code for proteins with similarity to the n-terminal domain of the mycolic acid transferase ps1 of the related c. glutamicum strain atcc 17965. the genes identified were designated cop1, cmt1, cmt2, cmt3, cmt4, and cmt5 ( cmt from corynebacterium mycolyl transferases). cop1 encodes a protein of 657 amino acids, which is larger than the proteins encoded by ... | 2003 | 12740729 |
| the corynebacterium glutamicum genome: features and impacts on biotechnological processes. | corynebacterium glutamicum has played a principal role in the progress of the amino acid fermentation industry. the complete genome sequence of the representative wild-type strain of c. glutamicum, atcc 13032, has been determined and analyzed to improve our understanding of the molecular biology and physiology of this organism, and to advance the development of more efficient production strains. genome annotation has helped in elucidation of the gene repertoire defining a desired pathway, which ... | 2003 | 12743753 |
| engineering metabolism and product formation in corynebacterium glutamicum by coordinated gene overexpression. | single gene overexpression in product pathways such as lysine synthesis has often been employed in metabolic engineering efforts aiming at pathway flux amplification and metabolite overproduction. this approach is limited due to metabolic flux imbalances that often lead to unpredictable physiological responses and suboptimal metabolite productivity. this deficiency can be overcome by the coordinated overexpression of more than one flux controlling genes in a production pathway selected by consid ... | 2003 | 12749842 |
| host-vector system for phenol-degrading rhodococcus erythropolis based on corynebacterium plasmids. | the strain rhodococcus erythropolis ccm2595, which was shown to degrade phenol, was chosen for genetic studies. to facilitate strain improvement using the methods of gene manipulation, the technique of genetic transfer was introduced and cloning vectors were constructed. using the plasmid pfaj2574, an electrotransformation procedure yielding up to 7x10(4) transformants/microg dna was optimized. escherichia coli- r. erythropolis shuttle vectors were constructed using the replicons psr1 and pga1 f ... | 2003 | 12764568 |
| the putative transcriptional repressor mcbr, member of the tetr-family, is involved in the regulation of the metabolic network directing the synthesis of sulfur containing amino acids in corynebacterium glutamicum. | in order to isolate transcriptional regulatory proteins involved in l-methionine-dependent repression in corynebacterium glutamicum, proteins binding to the putative promoter region upstream of the mety gene were isolated by dna affinity chromatography. one of the isolated proteins was identified as a putative transcriptional repressor of the tetr-family by a mass spectrometry fingerprint technique based on the complete c. glutamicum genome sequence. the respective gene, designated mcbr, was del ... | 2003 | 12770504 |
| a single v317a or v317m substitution in enzyme ii of a newly identified beta-glucoside phosphotransferase and utilization system of corynebacterium glutamicum r extends its specificity towards cellobiose. | a catabolic system involved in the utilization of beta-glucosides in corynebacterium glutamicum r and its spontaneous mutant variants allowing uptake of cellobiose were investigated. the system comprises a beta-glucoside-specific enzyme iibca component (gene bglf) of the phosphotransferase system (pts), a phospho-beta-glucosidase (bgla) and an antiterminator protein (bglg) from the bglg/sacy family of transcription regulators. the results suggest that transcription antitermination is involved in ... | 2003 | 12777497 |
| improved vectors for transcriptional/translational signal screening in corynebacteria using the melc operon from streptomyces glaucescens as reporter. | the tyrosinase operon ( melc) from streptomyces glaucescens was cloned and functionally expressed in brevibacterium lactofermentum and corynebacterium glutamicum under the control of the promoter of the kan gene from tn 5. recombinant corynebacterial cells containing the tyrosinase operon produced melanin on agar plates and in liquid culture when supplemented with copper and tyrosine. a conjugative bifunctional replacement vector for transcriptional/translational signal screening (pemel-1) was c ... | 2003 | 12802479 |
| modified glycopeptides related to cell wall peptidoglycan: conformational studies by nmr and molecular modelling. | polymeric peptidoglycans of bacterial cell walls, and smaller glycopeptides derived from them, exhibit versatile biological activities including immunomodulating properties. peptidoglycan monomer (pgm) was isolated from brevibacterium divaricatum and novel lipophilic derivatives of pgm bearing either (adamantyl-1-yl)-acetyl or boc-tyr substituents (ad-pgm and boctyr-pgm respectively) have recently been synthesized. we have obtained full assignments of the 1h and 13c spectra, using 2d nmr techniq ... | 2003 | 12818676 |
| a novel polygalacturonic acid bioflocculant rea-11 produced by corynebacterium glutamicum: a proposed biosynthetic pathway and experimental confirmation. | corynebacterium glutamicum cctcc m201005 produces a novel polygalacturonic acid bioflocculant, rea-11, consisting of galacturonic acid as the main structural unit. a biosynthetic pathway of rea-11 in c. glutamicum cctcc m201005 was proposed. evidence for the biosynthetic pathway was provided by: (1) analyzing the response upon addition of udp-glucose to the culture medium; (2) detecting the presence of several key intermediates in the pathway; and (3) correlating the activities of several key en ... | 2003 | 12827320 |
| efficient 40 degrees c fermentation of l-lysine by a new corynebacterium glutamicum mutant developed by genome breeding. | we have recently developed a new l-lysine-producing mutant of corynebacterium glutamicum by "genome breeding" consisting of characterization and reconstitution of a mutation set essential for high-level production. the strain ahp-3 was examined for l-lysine fermentation on glucose at temperatures above 35 degrees c, at which no examples of efficient l-lysine production have been reported for this organism. we found that the strain had inherited the thermotolerance that the original coryneform ba ... | 2003 | 12835923 |
| characterization and molecular cloning of a novel enzyme, inorganic polyphosphate/atp-glucomannokinase, of arthrobacter sp. strain km. | a bacterium exhibiting activities of several inorganic polyphosphate [poly(p)]- and atp-dependent kinases, including glucokinase, nad kinase, mannokinase, and fructokinase, was isolated, determined to belong to the genus arthrobacter, and designated arthrobacter sp. strain km. among the kinases, a novel enzyme responsible for the poly(p)- and atp-dependent mannokinase activities was purified 2,200-fold to homogeneity from a cell extract of the bacterium. the purified enzyme was a monomer with a ... | 2003 | 12839753 |
| comparative complete genome sequence analysis of the amino acid replacements responsible for the thermostability of corynebacterium efficiens. | corynebacterium efficiens is the closest relative of corynebacterium glutamicum, a species widely used for the industrial production of amino acids. c. efficiens but not c. glutamicum can grow above 40 degrees c. we sequenced the complete c. efficiens genome to investigate the basis of its thermostability by comparing its genome with that of c. glutamicum. the difference in gc content between the species was reflected in codon usage and nucleotide substitutions. our comparative genomic study cle ... | 2003 | 12840036 |
| methionine biosynthesis and its regulation in corynebacterium glutamicum: parallel pathways of transsulfuration and direct sulfhydrylation. | there are two alternative pathways leading to methionine synthesis in microorganisms: the transsulfuration pathway involves cystathionine as the intermediate and utilizes cysteine as the sulfur source, but the direct sulfhydrylation pathway bypasses cystathionine and uses inorganic sulfur instead. while most microorganisms synthesize methionine via either one of these pathways, corynebacterium glutamicum utilizes both pathways, which appear to be fully functional. in c. glutamicum, each pathway ... | 2003 | 12845493 |
| production process monitoring by serial mapping of microbial carbon flux distributions using a novel sensor reactor approach: ii--(13)c-labeling-based metabolic flux analysis and l-lysine production. | corynebacterium glutamicum is intensively used for the industrial large-scale (fed-) batch production of amino acids, especially glutamate and lysine. however, metabolic flux analyses based on 13c-labeling experiments of this organism have hitherto been restricted to small-scale batch conditions and carbon-limited chemostat cultures, and are therefore of questionable relevance for industrial fermentations. to lever flux analysis to the industrial level, a novel sensor reactor approach was develo ... | 2003 | 12850132 |
| new insights into the biogenesis of the cell envelope of corynebacteria: identification and functional characterization of five new mycoloyltransferase genes in corynebacterium glutamicum. | mycolic acids, the major lipid constituents of corynebacterineae, play an essential role in maintaining the integrity of the bacterial cell envelope. we have previously characterized a corynebacterial mycoloyltransferase (ps1) homologous in its n-terminal part to the three known mycobacterial mycoloyltransferases, the so-called fibronectin-binding proteins a, b and c. the genomes of corynebacterium glutamicum (atcc13032 and cgl2005) and corynebacterium diphtheriae were explored for the occurrenc ... | 2003 | 12855165 |
| genetic dissection of trehalose biosynthesis in corynebacterium glutamicum: inactivation of trehalose production leads to impaired growth and an altered cell wall lipid composition. | the analysis of the available corynebacterium genome sequence data led to the proposal of the presence of all three known pathways for trehalose biosynthesis in bacteria, i.e. trehalose synthesis from udp-glucose and glucose 6-phosphate (otsa-otsb pathway), from malto-oligosaccharides or alpha-1,4-glucans (trey-trez pathway), or from maltose (tres pathway). inactivation of only one of the three pathways by chromosomal deletion did not have a severe impact on c. glutamicum growth, while the simul ... | 2003 | 12855718 |
| the phosphate starvation stimulon of corynebacterium glutamicum determined by dna microarray analyses. | the phosphate (p(i)) starvation stimulon of corynebacterium glutamicum was characterized by global gene expression analysis by using dna microarrays. hierarchical cluster analysis of the genes showing altered expression 10 to 180 min after a shift from p(i)-sufficient to p(i)-limiting conditions led to identification of five groups comprising 92 genes. four of these groups included genes which are not directly involved in p metabolism and changed expression presumably due to the reduced growth r ... | 2003 | 12867461 |
| new ubiquitous translocators: amino acid export by corynebacterium glutamicum and escherichia coli. | molecular access to amino acid excretion by corynebacterium glutamicum and escherichia coli led to the identification of structurally novel carriers and novel carrier functions. the exporters lyse, rhtb, thre and brnfe each represent the protoype of new transporter families, which are in part distributed throughout all of the kingdoms of life. lyse of c. glutamicum catalytes the export of basic amino acids. the expression of the carrier gene is regulated by the cell-internal concentration of bas ... | 2003 | 12879215 |
| characterization and application of an optical sensor for quantification of dissolved o2 in shake-flasks. | on-line measurement of dissolved o2 in shake-flasks was realized via immobilized sensor spots containing a fluorophore with an o2-dependent luminescent decay time. an unaffected sensor signal during 80 autoclaving cycles suggests multi-usage of sensor equipped shake-flasks. the sensor had a response time of 6 s. quantification of gas-liquid mass transfer revealed maximum kla values of 150 h(-1), from which maximum o2 transfer capacity of 33 mm h(-1) was calculated. liquid volume and shaking freq ... | 2003 | 12882556 |
| three pathways for trehalose metabolism in corynebacterium glutamicum atcc13032 and their significance in response to osmotic stress. | genome scanning of corynebacterium glutamicum atcc13032 revealed the presence of five different genes encoding enzymes belonging to three putative trehalose biosynthesis pathways (otsab, treyz, tres). the function of the different pathways and of trehalose as an osmoprotectant was studied by characterizing several strains defective for individual trehalose biosynthetic routes. trehalose synthesis was shown to increase upon hyperosmotic conditions. cytoplasmic trehalose levels varied considerably ... | 2003 | 12890033 |
| unstructured model for l-lysine fermentation under controlled dissolved oxygen. | an unstructured model was developed for batch cultivation of corynebacterium lactofermentum (atcc 21799) under controlled dissolved oxygen. the model is capable of predicting batch experiments performed at various initial substrate concentrations. by extending the batch culture model to a fed-batch model and using a heuristic approach to optimize the fed-batch cultivation, it is shown that fed-batch cultivation is superior to batch operation due to increased productivity at high substrate concen ... | 2003 | 12892508 |
| pora represents the major cell wall channel of the gram-positive bacterium corynebacterium glutamicum. | the cell wall of the gram-positive bacterium corynebacterium glutamicum contains a channel (porin) for the passage of hydrophilic solutes. the channel-forming polypeptide pora is a 45-amino-acid acidic polypeptide with an excess of four negatively charged amino acids, which is encoded by the 138-bp gene pora. pora was deleted from the chromosome of c.glutamicum wild-type strain atcc 13032 to obtain mutant atcc 13032deltapora. southern blot analysis demonstrated that pora was deleted. lipid bilay ... | 2003 | 12896997 |
| cloning and expression of the inorganic pyrophosphatase gene from the amino acid producer brevibacterium lactofermentum atcc 13869. | a 20-kda brevibacterium lactofermentum protein was detected when purifying the his-tagged ftszbl. the protein was identified by matrix-assisted laser desorption/ionisation time of flight as the inorganic pyrophosphatase encoded by the ppa gene, which is present as a single copy in the genome of corynebacterium glutamicum. the ppa gene was cloned from b. lactofermentum chromosomal dna by polymerase chain reaction; it seemed to be an essential gene and it might represent an attractive target for d ... | 2003 | 12900025 |
| chloride dependence of growth in bacteria. | chloride is an abundant anion on earth but studies analyzing a possible function of chloride in prokaryotes are scarce. to address the question, we have tested 44 different gram-negative and gram-positive bacteria for a chloride dependence or chloride stimulation of growth. none required chloride for growth at their optimal growth (salt) conditions. however, in hyperosmotic media containing high concentrations of na+, 11 bacteria (aeromonas hydrophila, bacillus megaterium, bacillus subtilis, cor ... | 2003 | 12900036 |
| disruption of cg-ppm1, a polyprenyl monophosphomannose synthase, and the generation of lipoglycan-less mutants in corynebacterium glutamicum. | the glycosyl donor, polyprenyl monophosphomannose (ppm), has been shown to be involved in the biosynthesis of the mycobacterial lipoglycans: lipomannan and lipoarabinomannan. the mycobacterial ppm synthase (mt-ppm1) catalyzes the transfer of mannose from gdp-mannose to polyprenyl phosphates. based on sequence homology to mt-ppm1, we have identified the ppm synthase from corynebacterium glutamicum. in the present study, we demonstrate that the corynebacterial synthase is composed of two distinct ... | 2003 | 12904287 |
| fructose-1,6-bisphosphatase from corynebacterium glutamicum: expression and deletion of the fbp gene and biochemical characterization of the enzyme. | the class ii fructose-1,6-bisphosphatase gene of corynebacterium glutamicum, fbp, was cloned and expressed with a n-terminal his-tag in escherichia coli. purified, his-tagged fructose-1,6-bisphosphatase from c. glutamicum was shown to be tetrameric, with a molecular mass of about 140 kda for the homotetramer. the enzyme displayed michaelis-menten kinetics for the substrate fructose 1,6-bisphosphate with a k(m) value of about 14 micro m and a v(max) of about 5.4 micro mol min(-1) mg(-1) and k(cat ... | 2003 | 12904832 |
| systematic quantification of complex metabolic flux networks using stable isotopes and mass spectrometry. | metabolic fluxes provide a detailed metric of the cellular metabolic phenotype. fluxes are estimated indirectly from available measurements and various methods have been developed for this purpose. of particular interest are methods making use of stable isotopic tracers as they enable the estimation of fluxes at a high resolution. in this paper, we present data validating the use of mass spectrometry (ms) for the quantification of complex metabolic flux networks. in the context of the lysine bio ... | 2003 | 12919317 |
| towards a phosphoproteome map of corynebacterium glutamicum. | in this study, the phosphoproteome of corynebacterium glutamicum, an industrially important soil bacterium of the corynebacterium/mycobacterium/nocardia (cmn) group of gram-positive bacteria, was investigated by two different detection methods: first, by in vivo radio-labeling using [(33)p]-phosphoric acid with subsequent autoradiography and second, by immunostaining with phosphoamino acid-specific monoclonal antibodies. after two-dimensional gel electrophoresis (2-de), around 60 [(33)p]-labeled ... | 2003 | 12923788 |
| crystallization and preliminary x-ray crystallographic studies of phosphoenolpyruvate carboxykinase from corynebacterium glutamicum. | phosphoenolpyruvate carboxykinase (pck) is a key enzyme involved in the regulation of gluconeogenesis. pcks from higher animals require guanosine nucleotide for activity. pck from corynebacterium glutamicum is also gtp specific. x-ray diffraction data from a c. glutamicum pck crystal were collected to 2.8 a resolution. the crystals were monoclinic, belonging to space group p2(1), with unit-cell parameters a = 71.7, b = 117.4, c = 161.3 a, beta = 92.9 degrees. the presence of two molecules in the ... | 2003 | 12925798 |
| a gene homologous to beta-type carbonic anhydrase is essential for the growth of corynebacterium glutamicum under atmospheric conditions. | carbonic anhydrase catalyzes the interconversion of co(2) and bicarbonate. we focused on this enzyme in the amino acid-producing organism corynebacterium glutamicum in order to assess the availability of bicarbonate for carboxylation reactions essential to growth and for those required for l-lysine overproduction. a whole-genome sequence revealed two genes encoding putative beta-type and gamma-type carbonic anhydrases in c. glutamicum. these genes encode polypeptides containing zinc ligands stri ... | 2004 | 12937954 |
| the complete corynebacterium glutamicum atcc 13032 genome sequence and its impact on the production of l-aspartate-derived amino acids and vitamins. | the complete genomic sequence of corynebacterium glutamicum atcc 13032, well-known in industry for the production of amino acids, e.g. of l-glutamate and l-lysine was determined. the c. glutamicum genome was found to consist of a single circular chromosome comprising 3282708 base pairs. several dna regions of unusual composition were identified that were potentially acquired by horizontal gene transfer, e.g. a segment of dna from c. diphtheriae and a prophage-containing region. after automated a ... | 2003 | 12948626 |
| plasmids in corynebacterium glutamicum and their molecular classification by comparative genomics. | endogenous plasmids and selectable resistance markers are a fundamental prerequisite for the development of efficient recombinant dna techniques in industrial microorganisms. in this article, we therefore summarize the current knowledge about endogenous plasmids in amino acid-producing corynebacterium glutamicum isolates. screening studies identified a total of 24 different plasmids ranging in size from 2.4 to 95 kb. although most of the c. glutamicum plasmids were cryptic, four plasmids carried ... | 2003 | 12948627 |
| ribosomal rna and ribosomal proteins in corynebacteria. | ribosomal rnas (rrnas) (16s, 23s, 5s) encoded by the rrn operons and ribosomal proteins play a very important role in the formation of ribosomes and in the control of translation. five copies of the rrn operon were reported by hybridization studies in brevibacterium (corynebacterium) lactofermentum but the genome sequence of corynebacterium glutamicum provided evidence for six rrn copies. all six copies of the c. glutamicum 16s rrna have a size of 1523 bp and each of the six copies of the 5s con ... | 2003 | 12948628 |
| mycomembrane and s-layer: two important structures of corynebacterium glutamicum cell envelope with promising biotechnology applications. | corynebacteria belong to a distinct gram-positive group of bacteria including mycobacteria and nocardia, which are characterized by the presence of mycolic acids in their cell wall. these bacteria share the property of having an unusual cell envelope structural organization close to gram-negative bacteria. in addition to the inner membrane, the cell envelope is constituted of a thick arabinogalactan-peptidoglycan polymer covalently linked to an outer lipid layer, which is mainly composed of myco ... | 2003 | 12948629 |
| impact of transport processes in the osmotic response of corynebacterium glutamicum. | osmoregulation, the adaptation of cells to changes in the external osmolarity, is an important aspect of the bacterial stress response, in particular for a soil bacterium like corynebacterium glutamicum. consequently, this organism is equipped with several redundant systems for coping with both hyper- and hypoosmotic stress. for the adaptation to hypoosmotic stress c. glutamicum possesses at least three different mechanosensitive (ms) channels. to overcome hyperosmotic stress c. glutamicum accum ... | 2003 | 12948630 |
| osmotic stress, glucose transport capacity and consequences for glutamate overproduction in corynebacterium glutamicum. | glucose uptake by corynebacterium glutamicum is predominantly assured by a mannose phosphotransferase system (pts) with a high affinity for glucose (km=0.35 mm). mutants selected for their resistance to 2-deoxyglucose (2dg) and lacking detectable pep-dependent glucose-transporting activity, retained the capacity to grow on media in which glucose was the only carbon and energy source, albeit at significantly diminished rates, due to the presence of a low affinity (ks=11 mm) non-pts uptake system. ... | 2003 | 12948631 |
| impact of osmotic stress on volume regulation, cytoplasmic solute composition and lysine production in corynebacterium glutamicum mh20-22b. | the response of the l-lysine producing corynebacterium glutamicum strain mh20-22b to osmotic stress was studied in batch cultures. to mimic the conditions during a fermentation process the long term adaptation of cells subjected to a constant osmotic stress between 1.0 and 2.5 osm was investigated. cytoplasmic water content and volume of c. glutamicum cells were found to depend on growth phase, extent of osmotic stress and availability of betaine. the maximal cytoplasmic volumes, which were high ... | 2003 | 12948632 |
| acetate metabolism and its regulation in corynebacterium glutamicum. | the amino acid producing corynebacterium glutamicum grows aerobically on a variety of carbohydrates and organic acids as single or combined sources of carbon and energy. among the substrates metabolized are glucose and acetate which both can also serve as substrates for amino acid production. based on biochemical, genetic and regulatory studies and on quantitative determination of metabolic fluxes during utilization of acetate and/or glucose, this review summarizes the present knowledge on the d ... | 2003 | 12948633 |
| lysine synthesis control in corynebacterium glutamicum rc 115 in mixed substrate (glucose-acetate) medium. | the effect of acetate as a glucose co-substrate on growth, lysine synthesis and experimental lysine yield from carbon substrates by corynebacterium glutamicum rc 115 was investigated. it was found that low amounts of acetate, injected with a glucose-acetate pulse into the steady-state continuous culture in bioreactor, caused a slight decrease in the specific rates of glucose uptake and bacterial growth, but a significant increase in the cell specific rate of lysine synthesis and an increase in l ... | 2003 | 12948634 |
| the respiratory chain of corynebacterium glutamicum. | corynebacterium glutamicum is an aerobic bacterium that requires oxygen as exogenous electron acceptor for respiration. recent molecular and biochemical analyses together with information obtained from the genome sequence showed that c. glutamicum possesses a branched electron transport chain to oxygen with some remarkable features. reducing equivalents obtained by the oxidation of various substrates are transferred to menaquinone via at least eight different dehydrogenases, i.e. nadh dehydrogen ... | 2003 | 12948635 |
| industrial production of amino acids by coryneform bacteria. | in the 1950s corynebacterium glutamicum was found to be a very efficient producer of l-glutamic acid. since this time biotechnological processes with bacteria of the species corynebacterium developed to be among the most important in terms of tonnage and economical value. l-glutamic acid and l-lysine are bulk products nowadays. l-valine, l-isoleucine, l-threonine, l-aspartic acid and l-alanine are among other amino acids produced by corynebacteria. applications range from feed to food and pharma ... | 2003 | 12948636 |