| emerging corynebacterium glutamicum systems biology. | corynebacterium glutamicum is widely used for the biotechnological production of amino acids. amino acid producing strains have been improved classically by mutagenesis and screening as well as in a rational manner using recombinant dna technology. metabolic flux analysis may be viewed as the first systems approach to c. glutamicum physiology since it combines isotope labeling data with metabolic network models of the biosynthetic and central metabolic pathways. however, only the complete genome ... | 2006 | 16406159 |
| secretion of human epidermal growth factor by corynebacterium glutamicum. | to examine the secretion of human epidermal growth factor (hegf) by corynebacterium glutamicum. | 2006 | 16411922 |
| substrate-free structure of a monomeric nadp isocitrate dehydrogenase: an open conformation phylogenetic relationship of isocitrate dehydrogenase. | both monomeric and dimeric nadp+-dependent isocitrate dehydrogenase (idh) belong to the metal-dependent beta-decarboxylating dehydrogenase family and catalyze the oxidative decarboxylation from 2r,3s-isocitrate to yield 2-oxoglutarate, co2, and nadph. it is important to solve the structures of idhs from various species to correlate with its function and evolutionary significance. so far, only two crystal structures of substrate/cofactor-bound (isocitrate/nadp) nadp+-dependent monomeric idh from ... | 2006 | 16416443 |
| influence of membrane composition on osmosensing by the betaine carrier betp from corynebacterium glutamicum. | the glycine betaine carrier betp from corynebacterium glutamicum was recently shown to function as both an osmosensor and osmoregulator in proteoliposomes made from escherichia coli phospholipids by sensing changes in the internal k+ concentration as a measure of hyperosmotic stress (rübenhagen, r., morbach, s., and krämer, r. (2001) embo j. 20, 5412-5420). furthermore, evidence was provided that a stretch of 25 amino acids of the c-terminal domain of betp is critically involved in k+ sensing. t ... | 2006 | 16421104 |
| changes in composition and content of mycolic acids in glutamate-overproducing corynebacterium glutamicum. | overproduction of glutamate by corynebacterium glutamicum is induced by biotin limitation or by the supplementation of specific detergents, sublethal amounts of penicillin, or cerulenin. but, it remains unclear why these different treatments, which have different sites of primary action, produce similar effects. in this study, it was found that the cellular content of mycolic acids--characteristic constituents of corynebacterineae that are synthesized from fatty acids and form a cell surface lay ... | 2006 | 16428817 |
| functional analysis of l-serine o-acetyltransferase from corynebacterium glutamicum. | we report here the function of l-serine o-acetyltransferase (sat) from the glutamic acid-producing bacterium corynebacterium glutamicum. based on the genome sequence of c. glutamicum and the nh(2)-terminal amino-acid sequence, the gene encoding sat (cyse) was cloned and expressed in c. glutamicum. deletion analysis of the 5'-noncoding region showed a putative -10 region ((-27)ttaagt(-22) or (-26)taagtc(-21)) and a possible ribosome-binding site ((-12)aga(-10)) just upstream from the start codon. ... | 2006 | 16436075 |
| pyruvate:quinone oxidoreductase in corynebacterium glutamicum: molecular analysis of the pqo gene, significance of the enzyme, and phylogenetic aspects. | corynebacterium glutamicum recently has been shown to possess pyruvate:quinone oxidoreductase (pqo), catalyzing the oxidative decarboxylation of pyruvate to acetate and co2 with a quinone as the electron acceptor. here, we analyze the expression of the c. glutamicum pqo gene, investigate the relevance of the pqo enzyme for growth and amino acid production, and perform phylogenetic studies. expression analyses revealed that transcription of pqo is initiated 45 bp upstream of the translational sta ... | 2006 | 16452416 |
| the dtxr protein acting as dual transcriptional regulator directs a global regulatory network involved in iron metabolism of corynebacterium glutamicum. | the knowledge about complete bacterial genome sequences opens the way to reconstruct the qualitative topology and global connectivity of transcriptional regulatory networks. since iron is essential for a variety of cellular processes but also poses problems in biological systems due to its high toxicity, bacteria have evolved complex transcriptional regulatory networks to achieve an effective iron homeostasis. here, we apply a combination of transcriptomics, bioinformatics, in vitro assays, and ... | 2006 | 16469103 |
| the gene ncgl2918 encodes a novel maleylpyruvate isomerase that needs mycothiol as cofactor and links mycothiol biosynthesis and gentisate assimilation in corynebacterium glutamicum. | data mining of the corynebacterium glutamicum genome identified 4 genes analogous to the msha, mshb, mshc, and mshd genes that are involved in biosynthesis of mycothiol in mycobacterium tuberculosis and mycobacterium smegmatis. individual deletion of these genes was carried out in this study. mutants mshc- and mshd- lost the ability to produce mycothiol, but mutant mshb- produced mycothiol as the wild type did. the phenotypes of mutants mshc- and mshd- were the same as the wild type when grown i ... | 2006 | 16481315 |
| utilization of soluble starch by a recombinant corynebacterium glutamicum strain: growth and lysine production. | corynebacterium glutamicum, well known for the industrial production of amino acids, grows aerobically on a variety of mono- and disaccharides and on alcohols and organic acids as single or combined sources of carbon and energy. members of the genera corynebacterium and brevibacterium were here tested for their ability to use the homopolysaccharide starch as a substrate for growth. none of the 24 type strains tested showed growth on or degradation of this substrate, indicating that none of the s ... | 2006 | 16488498 |
| transcriptome analysis reveals global expression changes in an industrial l-lysine producer of corynebacterium glutamicum. | toward the elucidation of advanced mechanisms of l-lysine production by corynebacterium glutamicum, a highly developed industrial strain b-6 was analyzed from the viewpoint of gene expression. northern blot analysis showed that the lysc gene encoding aspartokinase, the key enzyme of l-lysine biosynthesis, was up-regulated by several folds in strain b-6, while no repression mechanism exists in l-lysine biosynthesis of this bacterium. to analyze the underlying mechanisms of the up-regulation, we c ... | 2006 | 16495679 |
| a genome-based approach to create a minimally mutated corynebacterium glutamicum strain for efficient l-lysine production. | based on the progress in genomics, we have developed a novel approach that employs genomic information to generate an efficient amino acid producer. a comparative genomic analysis of an industrial l-lysine producer with its natural ancestor identified a variety of mutations in genes associated with l-lysine biosynthesis. among these mutations, we identified two mutations in the relevant terminal pathways as key mutations for l-lysine production, and three mutations in central metabolism that res ... | 2006 | 16506038 |
| protein cleavage strategies for an improved analysis of the membrane proteome. | membrane proteins still remain elusive in proteomic studies. this is in part due to the distribution of the amino acids lysine and arginine, which are less frequent in integral membrane proteins and almost absent in transmembrane helices. as these amino acids are cleavage targets for the commonly used protease trypsin, alternative cleavage conditions, which should improve membrane protein analysis, were tested by in silico digestion for the three organisms saccharomyces cerevisiae, halobacterium ... | 2006 | 16512920 |
| metabolic engineering of corynebacterium glutamicum for trehalose overproduction: role of the treyz trehalose biosynthetic pathway. | trehalose has many potential applications in biotechnology and the food industry due to its protective effect against environmental stress. our work explores microbiological production methods based on the capacity of corynebacterium glutamicum to excrete trehalose. we address here raising trehalose productivity through homologous overexpression of maltooligosyltrehalose synthase and the maltooligosyltrehalose trehalohydrolase genes. in addition, heterologous expression of the udp-glucose pyroph ... | 2006 | 16517642 |
| corynebacterial protein kinase g controls 2-oxoglutarate dehydrogenase activity via the phosphorylation status of the odhi protein. | a novel regulatory mechanism for control of the ubiquitous 2-oxoglutarate dehydrogenase complex (odh), a key enzyme of the tricarboxylic acid cycle, was discovered in the actinomycete corynebacterium glutamicum, a close relative of important human pathogens like corynebacterium diphtheriae and mycobacterium tuberculosis. based on the finding that a c. glutamicum mutant lacking serine/threonine protein kinase g (pkng) was impaired in glutamine utilization, proteome comparisons led to the identifi ... | 2006 | 16522631 |
| mechanism and regulation of isoleucine excretion in corynebacterium glutamicum. | whole cells of corynebacterium glutamicum were loaded with high cytoplasmic l-isoleucine concentrations, and isoleucine excretion from these cells was studied in terms of mechanism and regulation. the transmembrane isoleucine flux could be differentiated into carrier-mediated uptake, carrier-mediated excretion, and diffusion. after discrimination from the other transmembrane solute movements, the outward-directed flux, which was due to the activity of the isoleucine excretion carrier, was charac ... | 1996 | 16535397 |
| complete sucrose metabolism requires fructose phosphotransferase activity in corynebacterium glutamicum to ensure phosphorylation of liberated fructose. | sucrose uptake by corynebacterium glutamicum involves a phosphoenolpyruvate-dependent sucrose phosphotransferase (pts), but in the absence of fructokinase, further metabolism of the liberated fructose requires efflux of the fructose and reassimilation via the fructose pts. mutant strains lacking detectable fructose-transporting pts activity accumulated fructose extracellularly but consumed sucrose at rates comparable to those of the wild-type strain. | 1996 | 16535429 |
| l-isoleucine production with corynebacterium glutamicum: further flux increase and limitation of export. | the synthesis of l-isoleucine with corynebacterium glutamicum involves 11 reaction steps, in at least five of which activity or expression is regulated. we used four genes and alleles encoding feedback-resistant enzymes (fbr) in various combinations to assay flux increase through the sequence. during strain construction, the order of genes overexpressed was important. only when ilva(fbr) was first overexpressed could hom(fbr) be introduced. this succession apparently prevents the toxic accumulat ... | 1996 | 16535457 |
| protein and proteome phosphorylation stoichiometry analysis by element mass spectrometry. | protein phosphorylation stoichiometry was assessed by two analytical strategies. both are based on element mass spectrometry (icpms, inductively coupled plasma mass spectrometry) and simultaneous monitoring of (31)p and (34)s. one strategy employs a combination of 1d gel electrophoresis, in-gel digestion, and final microlc-icpms analysis (microlc = capillary liquid chromatography). the other strategy uses the combination of 1d gel electrophoresis, protein blotting, and imla-icpms (imla = imaging ... | 2006 | 16536437 |
| identification of rama, a novel luxr-type transcriptional regulator of genes involved in acetate metabolism of corynebacterium glutamicum. | in corynebacterium glutamicum, the acetate-activating enzymes phosphotransacetylase and acetate kinase and the glyoxylate cycle enzymes isocitrate lyase and malate synthase are coordinately up-regulated in the presence of acetate in the growth medium. this regulation is due to transcriptional control of the respective pta-ack operon and the acea and aceb genes, brought about at least partly by the action of the negative transcriptional regulator ramb. using cell extracts of c. glutamicum and emp ... | 2006 | 16547043 |
| the surface (s)-layer gene cspb of corynebacterium glutamicum is transcriptionally activated by a luxr-type regulator and located on a 6 kb genomic island absent from the type strain atcc 13032. | the surface (s)-layer gene region of the gram-positive bacterium corynebacterium glutamicum atcc 14067 was identified on fosmid clones, sequenced and compared with the genome sequence of c. glutamicum atcc 13032, whose cell surface is devoid of an ordered s-layer lattice. a 5.97 kb dna region that is absent from the c. glutamicum atcc 13032 chromosome was identified. this region includes cspb, the structural gene encoding the s-layer protomer ps2, and six additional coding sequences. pcr experim ... | 2006 | 16549657 |
| oxygen limitation is a pitfall during screening for industrial strains. | oxygen supply is a key parameter in aerobic fermentation processes like the industrial production of amino acids. although the oxygen transfer rate (otr; or the volumetric oxygen transfer coefficient k(l)a) is routinely analyzed by engineers during stirred tank fermentations, it is often not taken into account by biologists conducting screening experiments in shake flasks. to show the importance of knowing how to avoid oxygen transfer limitations during primary screenings, corynebacterium glutam ... | 2006 | 16575561 |
| [cloning, sequence analysis and expression of n-acetylglutamate kinase gene in corynebacterium crenatum]. | n-acetylglutamate kinase (ec 2.7.2.8;nagk) genes from wild-type corynebacterium crenatum as 1.542 and a l-arginine-producing mutant c. crenatum 971.1 were cloned and sequenced. analysis of argb sequences revealed that only one orf existed, which used atg as the initiation codon and coded a peptide of 317 amino acids with a calculated molecular weight of 33.6kda. only one nucleotide difference was found in the structure gene and the difference did not cause a change of amino acid by comparison of ... | 2006 | 16579472 |
| the dtxr regulon of corynebacterium glutamicum. | previous studies with corynebacterium diphtheriae and mycobacterium species revealed that the transcriptional regulator dtxr and its ortholog ider play a central role in the control of iron metabolism. in the present work, we used genome-based approaches to determine the dtxr regulon of corynebacterium glutamicum, a nonpathogenic relative of c. diphtheriae. first, global gene expression of a dtxr deletion mutant was compared with that of the wild type using dna microarrays. second, we used a com ... | 2006 | 16585752 |
| identification of a novel arabinofuranosyltransferase (afta) involved in cell wall arabinan biosynthesis in mycobacterium tuberculosis. | the cell wall mycolyl-arabinogalactan-peptidoglycan complex is essential in mycobacterial species, such as mycobacterium tuberculosis, and is the target of several anti-tubercular drugs. for instance, ethambutol targets arabinogalactan biosynthesis through inhibition of the arabinofuranosyltransferases mt-emba and mt-embb. following a detailed bioinformatics analysis of genes surrounding the conserved emb locus, we present the identification and characterization of a novel arabinofuranosyltransf ... | 2006 | 16595677 |
| ammonium toxicity in bacteria. | although an excellent nitrogen source for most bacteria, ammonium was-in analogy to plant and animal systems-assumed be detrimental to bacteria when present in high concentrations. in this study, we examined the effect of molar ammonium concentrations on different model bacteria, namely, corynebacterium glutamicum, escherichia coli, and bacillus subtilis. the studied bacteria are highly resistant to ammonium. when growth was impaired upon addition of molar (nh4)2so4 concentrations, this was not ... | 2006 | 16604417 |
| on-line optimization of glutamate production based on balanced metabolic control by rq. | in glutamate fermentations by corynebacterium glutamicum, higher glutamate concentration could be achieved by constantly controlling dissolved oxygen concentration (do) at a lower level; however, by-product lactate also severely accumulated. the results of analyzing activities changes of the two key enzymes, glutamate and lactate dehydrogenases involved with the fermentation, and the entire metabolic network flux analysis showed that the lactate overproduction was because the metabolic flux in t ... | 2006 | 16614826 |
| metabolic engineering of escherichia coli and corynebacterium glutamicum for biotechnological production of organic acids and amino acids. | industrial microorganisms have been developed as biocatalysts to provide new or to optimize existing processes for the biotechnological production of chemicals from renewable plant biomass. rational strain development by metabolic engineering is crucial to successful processes, and is based on efficient genetic tools and detailed knowledge of metabolic pathways and their regulation. this review summarizes recent advances in metabolic engineering of the industrial model bacteria escherichia coli ... | 2006 | 16617034 |
| gene expression of corynebacterium glutamicum in response to the conditions inducing glutamate overproduction. | the ultimate aim is to elucidate the molecular mechanisms for glutamate overproduction by corynebacterium glutamicum. | 2006 | 16620205 |
| metabolic pathway analysis for rational design of l-methionine production by escherichia coli and corynebacterium glutamicum. | metabolic pathway analysis was carried out to predict the metabolic potential of corynebacterium glutamicum and escherichia coli for the production of l-methionine. based on detailed stoichiometric models for these organisms, this allowed the calculation of the theoretically optimal methionine yield and related metabolic fluxes for various scenarios involving different mutants and process conditions. the theoretical optimal methionine yield on the substrates glucose, sulfate and ammonia for the ... | 2006 | 16621639 |
| comparisons of potentials for l-lysine production among different corynebacterium glutamicum strains. | corynebacterium glutamicum is an industrially important organism that is most widely used for the production of various amino acids. a defined l-lysine-producing mutant was generated by introduction of the lysc mutation (t311i) into each of six representative c. glutamicum strains. the resulting six isogenic mutants were compared for l-lysine production under traditional 30 degrees c conditions and industrially more advantageous 40 degrees c conditions. it was found that there were significant d ... | 2006 | 16636474 |
| metabolic activity of corynebacterium glutamicum grown on l: -lactic acid under stress. | respiration measurement in shake flasks is introduced as a new method to characterize the metabolic activity of microorganisms during and after stress exposure. the major advantage of the new method is the possibility to determine the metabolic activity independent of manual sampling without the necessity to change the culture vessel or the cultivation medium. this excludes stress factors, which may be induced by transferring the microorganisms to plates or respirometers. the negative influence, ... | 2006 | 16642330 |
| structure and function of the betaine uptake system betp of corynebacterium glutamicum: strategies to sense osmotic and chill stress. | the soil bacterium corynebacterium glutamicum has to cope with frequent fluctuations of the external osmolarity and temperature. the consequences of hyperosmotic and chill stress seem to differ, either causing dehydration of the cytoplasm or leading to impairment of cellular functions due to low temperature. nevertheless, a particular type of regulatory response, namely the accumulation of so-called compatible solutes, is induced under both conditions. compatible solutes are known to stabilize t ... | 2005 | 16645311 |
| structure determination of secondary transport proteins by electron crystallography: two-dimensional crystallization of the betaine uptake system betp. | structure determination at high resolution is still a challenge for membrane proteins in general, but in particular for secondary transporters due to their highly dynamic nature. x-ray structures of ten secondary transporters have recently been determined, but a thorough understanding of transport mechanisms necessitates structures at different functional states. electron cryo-microscopy of two-dimensional (2d) crystals offers an alternative to obtain structural information at intermediate resol ... | 2005 | 16645315 |
| engineering of a xylose metabolic pathway in corynebacterium glutamicum. | the aerobic microorganism corynebacterium glutamicum was metabolically engineered to broaden its substrate utilization range to include the pentose sugar xylose, which is commonly found in agricultural residues and other lignocellulosic biomass. we demonstrated the functionality of the corynebacterial xylb gene encoding xylulokinase and constructed two recombinant c. glutamicum strains capable of utilizing xylose by cloning the escherichia coli gene xyla encoding xylose isomerase, either alone ( ... | 2006 | 16672486 |
| high-throughput transposon mutagenesis of corynebacterium glutamicum and construction of a single-gene disruptant mutant library. | a simple and high-throughput transposon-mediated mutagenesis system employing two different types of transposons in combination with direct genomic dna amplification and thermal asymmetric interlaced pcr (tail-pcr) was developed. each of the two minitransposons based on is31831 (isl3 family) and tn5 (is4 family) was integrated into the corynebacterium glutamicum r genome. by using blast and perl, transposon insertion locations were automatically identified based on the sequences of tail-pcr prod ... | 2006 | 16672528 |
| application of global analysis techniques to corynebacterium glutamicum: new insights into nitrogen regulation. | the regulation of nitrogen metabolism in the amino acid producer corynebacterium glutamicum was subject of research for several decades. while previous studies focused on single enzymes or pathways, the publication of the c. glutamicum genome sequence gave a fresh impetus to research, since a global investigation of metabolism and regulation networks became possible based on these data. this communication summarizes the advances made by different studies, in which global analysis approaches were ... | 2006 | 16698104 |
| expression of alr gene from corynebacterium glutamicum atcc 13032 in escherichia coli and molecular characterization of the recombinant alanine racemase. | we constructed the high-expression system of the alr gene from corynebacterium glutamicum atcc 13032 in escherichia coli bl 21 (de3) to characterize the enzymological and structural properties of the gene product, alr. the alr was expressed in the soluble fractions of the cell extract of the e. coli clone and showed alanine racemase activity. the purified alr was a dimer with a molecular mass of 78 kda. the alr required pyridoxal 5'-phosphate (plp) as a coenzyme and contained 2 mol of plp per mo ... | 2006 | 16707184 |
| purification and characterization of fumarase from corynebacterium glutamicum. | fumarase (ec 4.2.1.2) from corynebacterium glutamicum (brevibacterium flavum) atcc 14067 was purified to homogeneity. its amino-terminal sequence (residues 1 to 30) corresponded to the sequence (residues 6 to 35) of the deduced product of the fumarase gene of c. glutamicum (genbank accession no. bab98403). the molecular mass of the native enzyme was 200 kda. the protein was a homotetramer, with a 50-kda subunit molecular mass. the homotetrameric and stable properties indicated that the enzyme be ... | 2006 | 16717409 |
| the corynebacterium glutamicum gene pmt encoding a glycosyltransferase related to eukaryotic protein-o-mannosyltransferases is essential for glycosylation of the resuscitation promoting factor (rpf2) and other secreted proteins. | two-dimensional gel electrophoresis and immunoassays revealed several proteins of the secretory subproteome of corynebacterium glutamicum to be glycosylated. by genome-wide searches for genes involved in glycosylation, the c. glutamicum gene cg1014 was found to exhibit significant similarity to eukaryotic protein-o-mannosyltransferases (pmts) and to a recently identified orthologue of mycobacterium tuberculosis, rv1002c, which is responsible for protein-o-mannosylation. the putative membrane pro ... | 2006 | 16734784 |
| respirometric 13c flux analysis--part ii: in vivo flux estimation of lysine-producing corynebacterium glutamicum. | a novel method for metabolic flux studies of central metabolism which is based on respirometric (13)c flux analysis, i.e., parallel (13)c tracer studies with online co(2) labeling measurements is applied to flux quantification of a lysine-producing mutant of corynebacterium glutamicum. for this purpose, 3 respirometric (13)c labeling experiments with [1-(13)c(1)], [6-(13)c(1)] and [1,6-(13)c(2)] glucose were carried out in parallel. all fluxes comprising the reactions of glycolysis, of tca cycle ... | 2006 | 16750927 |
| heterologous expression and localization of gentisate transporter ncg12922 from corynebacterium glutamicum atcc 13032. | ralstonia sp. strain u2 metabolizes naphthalene via gentisate (2,5-dihydroxybenzoate) to central metabolites, but it was found unable to utilize gentisate as growth substrate. a putative gentisate transporter encoded by ncg12922 from corynebacterium glutamicum atcc 13032 was functionally expressed in ralstonia sp. strain u2, converting strain u2 to a gentisate utilizer. after ncg12922 was inserted into plasmid pgfpe with green fluorescence protein gene gfp, the expressed fusion protein ncg12922- ... | 2006 | 16765316 |
| corynebacterium glutamicum superoxide dismutase is a manganese-strict non-cambialistic enzyme in vitro. | superoxide dismutase (sod) of corynebacterium glutamicum was purified and characterized. the enzyme had a native molecular weight of about 80kda, whereas a monomer with molecular weight of 24kda was found on sds-page suggesting it to be homotetramer. the native sod activity stained gel revealed a unique cytosolic enzyme. supplementing growth media with manganese increased the specific activity significantly, while adding iron did not result in significant difference. no growth perturbation was o ... | 2008 | 16809027 |
| cloning, expression, purification and preliminary crystallographic characterization of a shikimate dehydrogenase from corynebacterium glutamicum. | the shikimate dehydrogenase from corynebacterium glutamicum has been cloned into an escherichia coli expression vector, overexpressed and purified. native crystals were obtained by the vapour-diffusion technique using 2-methyl-2,4-pentanediol as a precipitant. the crystals belong to the centred monoclinic space group c2, with unit-cell parameters a = 118.77, b = 63.17, c = 35.67 angstroms, beta = 92.26 degrees (at 100 k), and diffract to 1.64 angstroms on a synchrotron x-ray source. the asymmetr ... | 2006 | 16820680 |
| mutation-induced metabolite pool alterations in corynebacterium glutamicum: towards the identification of nitrogen control signals. | the influence of glutamate dehydrogenase activity on nitrogen regulation in corynebacterium glutamicum was investigated. as shown by rna hybridization experiments deletion of the gdh gene results in a rearrangement of nitrogen metabolism. even when sufficiently supplied with nitrogen sources, a gdh deletion strain showed the typical nitrogen starvation response of c. glutamicum. these changes in transcription correlate with distinct alterations of intracellular metabolite pattern. metabolite ana ... | 2006 | 16822574 |
| temperature-sensitive cloning vector for corynebacterium glutamicum. | we constructed a temperature-sensitive form of the corynebacterium glutamicum atcc13869 cryptic plasmid, pbl1. the c. glutamicum/escherichia coli shuttle vector psfk6, which is composed of pbl1 and the e. coli cloning vector pk1, was mutagenized in vitro by treatment with hydroxylamine, and introduced into c. glutamicum cells. a mutant plasmid, which was stably maintained at 25 degrees c but not at 34 degrees c, was isolated from the cells. sequencing the plasmid, which was named p48k, revealed ... | 2006 | 16828161 |
| respirometric 13c flux analysis, part i: design, construction and validation of a novel multiple reactor system using on-line membrane inlet mass spectrometry. | a novel method for (13)c flux analysis based on on-line co(2) labeling measurements is presented. this so-called respirometric (13)c flux analysis requires multiple parallel (13)c labeling experiments using differently labeled tracer substrates. in part i of the work, a membrane-inlet mass spectrometry-based measurement system with 6 parallel reactors with each 12 ml liquid volume and associated experimental and computational methods for the respirometric (13)c data acquisition and evaluation ar ... | 2006 | 16844397 |
| morphological changes and proteome response of corynebacterium glutamicum to a partial depletion of ftsi. | in corynebacterium glutamicum, as in many gram-positive bacteria, the cell division gene ftsi is located at the beginning of the dcw cluster, which comprises cell division- and cell wall-related genes. transcriptional analysis of the cluster revealed that ftsi is transcribed as part of a polycistronic mrna, which includes at least mraz, mraw, ftsl, ftsi and mure, from a promoter that is located upstream of mraz. ftsi appears also to be expressed from a minor promoter that is located in the inter ... | 2006 | 16849811 |
| growth rate-dependent modulation of carbon flux through central metabolism and the kinetic consequences for glucose-limited chemostat cultures of corynebacterium glutamicum. | the physiological behavior of corynebacterium glutamicum in glucose-limited chemostat cultures was examined from both growth kinetics and enzymatic viewpoints. metabolic fluxes within the central metabolism were calculated from growth kinetics and analyzed in relation to specific enzyme activities. at high growth rates, incomplete glucose removal was observed, and this was attributed to rate-limiting capacity of the phosphotransferase system transporter and the probable contribution of a low-aff ... | 1996 | 16535231 |
| triggering glutamate excretion in corynebacterium glutamicum by modulating the membrane state with local anesthetics and osmotic gradients. | corynebacterium glutamicum can be triggered to excrete glutamate by the addition of local anesthetics, particularly tetracaine. glutamate efflux is a carrier-mediated process and not due to unspecific membrane permeabilization. the concentration of local anesthetics triggering optimum excretion depended on the type of anesthetic and varied, ranging from 0.1 (chlorpromazine), 1.3 (tetracaine), and 2.6 mm (butacaine) to 15 mm (benzocaine), in close resemblance to the order of efficiency in anesthe ... | 1995 | 16535186 |
| use of feedback-resistant threonine dehydratases of corynebacterium glutamicum to increase carbon flux towards l-isoleucine. | the biosynthesis of l-isoleucine proceeds via a highly regulated reaction sequence connected with l-lysine and l-threonine synthesis. using defined genetic corynebacterium glutamicum strains characterized by different fluxes through the homoserine dehydrogenase reaction, we analyzed the influence of four different ilva alleles (encoding threonine dehydratase) in vectors with two different copy numbers on the total flux towards l-isoleucine. for this purpose, 18 different strains were constructed ... | 1995 | 16535185 |
| [effect of synthetic surfactants on some biological properties of non-pathogenic species of the genus corynebacterium]. | the influence of cationic, anionic and non-ionic synthetic surfactants on some biological properties of different representatives of the following species corynebacterium glutamicum, corynebacterium ammoniagenes, corynebacterium vitaeruminis, corynebacterium variabile and strain corynebacterium sp. (brevibacterium stationis) ukm as-719 has been investigated. it has been shown that the action of surfactants is accompanied by the change of cell morphology and loss of ability for gram-staining, as ... | 2006 | 16869145 |
| enhancement of l-lysine production in methylotroph methylophilus methylotrophus by introducing a mutant lyse exporter. | the obligate methylotroph methylophilus methylotrophus as1 expressing a mutant form of dapa (dapa24) encoding a dihydrodipicolinate synthase desensitized from feedback inhibition by l-lysine could secrete l-lysine into the medium, but also maintained a high concentration of intracellular l-lysine. to improve the yield from excretion, we attempted to introduce an l-lysine/l-arginine exporter (lyse) from corynebacterium glutamicum 2256 into m. methylotrophus. we were unable to stably transform m. ... | 2006 | 16870294 |
| utilization of fermentation waste (corynebacterium glutamicum) for biosorption of reactive black 5 from aqueous solution. | a fermentation waste, corynebacterium glutamicum, was successfully employed as a biosorbent for reactive black 5 (rb5) from aqueous solution. this paper initially studied the effect of pretreatment on the biosorption capacity of c. glutamicum toward rb5, using several chemical agents, such as hcl, h(2)so(4), hno(3), naoh, na(2)co(3), cacl(2) and nacl. among these reagents, 0.1m hno(3) gave the maximum enhancement of the rb5 uptake, exhibiting 195mg/g at ph 1 with an initial rb5 concentration of ... | 2007 | 16879915 |
| monitoring and modeling of the reaction dynamics in the valine/leucine synthesis pathway in corynebacterium glutamicum. | the intracellular concentrations of the valine and leucine pathway intermediates in a corynebacterium glutamicum strain were measured during a transient state. the data were obtained by performing a glucose stimulus-response experiment with the use of a rapid sampling device and advanced mass spectrometry. the glucose stimulus resulted in a 3-fold increase in the intracellular pyruvate concentration within less than a second, demonstrating the very fast interactions in metabolic networks. the sa ... | 2006 | 16889382 |
| arabinan-deficient mutants of corynebacterium glutamicum and the consequent flux in decaprenylmonophosphoryl-d-arabinose metabolism. | the arabinogalactan (ag) of corynebacterianeae is a critical macromolecule that tethers mycolic acids to peptidoglycan, thus forming a highly impermeable cell wall matrix termed the mycolyl-arabinogalactan peptidoglycan complex (magp). the front line anti-tuberculosis drug, ethambutol (emb), targets the mycobacterium tuberculosis and corynebacterium glutamicum arabinofuranosyltransferase mt-emba, mt-embb and cg-emb enzymes, respectively, which are responsible for the biosynthesis of the arabinan ... | 2006 | 16891347 |
| random mutagenesis in corynebacterium glutamicum atcc 13032 using an is6100-based transposon vector identified the last unknown gene in the histidine biosynthesis pathway. | corynebacterium glutamicum, a gram-positive bacterium of the class actinobacteria, is an industrially relevant producer of amino acids. several methods for the targeted genetic manipulation of this organism and rational strain improvement have been developed. an efficient transposon mutagenesis system for the completely sequenced type strain atcc 13032 would significantly advance functional genome analysis in this bacterium. | 2006 | 16901339 |
| siderophore-mediated iron transport in bacillus subtilis and corynebacterium glutamicum. | hexadentate bacillibactin is the siderophore of bacillus subtilis and is structurally similar to the better known enterobactin of gram-negative bacteria such as escherichia coli. although both are triscatecholamide trilactones, the structural differences of these two siderophores result in opposite metal chiralities, different affinity for ferric ion, and dissimilar iron transport behaviors. bacillibactin was first reported as isolated from corynebacterium glutamicum and called corynebactin. how ... | 2006 | 16912897 |
| proteomics of corynebacterium glutamicum: essential industrial bacterium. | | 2006 | 16929678 |
| markov chain monte carlo algorithm based metabolic flux distribution analysis on corynebacterium glutamicum. | metabolic flux analysis via a (13)c tracer experiment has been achieved using a monte carlo method with the assumption of system noise as gaussian noise. however, an unbiased flux analysis requires the estimation of fluxes and metabolites jointly without the restriction on the assumption of gaussian noise. the flux distributions under such a framework can be freely obtained with various system noise and uncertainty models. | 2006 | 16940326 |
| a leuc mutation leading to increased l-lysine production and rel-independent global expression changes in corynebacterium glutamicum. | we previously found by transcriptome analysis that global induction of amino acid biosynthetic genes occurs in a classically derived industrial l-lysine producer, corynebacterium glutamicum b-6. based on this stringent-like transcriptional profile in strain b-6, we analyzed the relevant mutations from among those identified in the genome of the strain, with special attention to the genes that are involved in amino acid biosynthesis and metabolism. among these mutations, a gly-456-->asp mutation ... | 2006 | 16944136 |
| one-pot synthesis of genistein from tyrosine by coincubation of genetically engineered escherichia coli and saccharomyces cerevisiae cells. | for production of genistein from n-acetylcysteamine-attached p-coumarate (p-coumaroyl-nac) supplemented to the medium, a chalcone synthase (chs) gene from glycyrrhiza echinata, a chalcone isomerase (chi) gene from pueraria lobata, and an isoflavone synthase (ifs) gene from g. echinata were placed under the control of the galactose-inducible gal promoters in pesc vector and were introduced in saccharomyces cerevisiae. when the recombinant yeast cells (0.5 g wet weight) were used as "enzyme bags" ... | 2007 | 16960736 |
| global gene expression during stringent response in corynebacterium glutamicum in presence and absence of the rel gene encoding (p)ppgpp synthase. | the stringent response is the initial reaction of microorganisms to nutritional stress. during stringent response the small nucleotides (p)ppgpp act as global regulators and reprogram bacterial transcription. in this work, the genetic network controlled by the stringent response was characterized in the amino acid-producing corynebacterium glutamicum. | 2006 | 16961923 |
| genetic characterization of the resorcinol catabolic pathway in corynebacterium glutamicum. | corynebacterium glutamicum grew on resorcinol as a sole source of carbon and energy. by genome-wide data mining, two gene clusters, designated ncgl1110-ncgl1113 and ncgl2950-ncgl2953, were proposed to encode putative proteins involved in resorcinol catabolism. deletion of the ncgl2950-ncgl2953 gene cluster did not result in any observable phenotype changes. disruption and complementation of each gene at ncgl1110-ncgl1113, ncgl2951, and ncgl2952 indicated that these genes were involved in resorci ... | 2006 | 16963551 |
| determination of soluble and granular inorganic polyphosphate in corynebacterium glutamicum. | corynebacterium glutamicum forms inorganic polyphosphate (poly p) that may occur as soluble (cytosolic) poly p and/or as volutin granules. a suitable method for monitoring soluble and granular poly p in c. glutamicum was developed and applied to c. glutamicum cells cultivated under different growth conditions. under phosphate-limiting conditions, c. glutamicum did not accumulate poly p, but it rebuilt its poly p storages when phosphate became available. the poly p content of c. glutamicum growin ... | 2006 | 16977467 |
| characterization of myo-inositol utilization by corynebacterium glutamicum: the stimulon, identification of transporters, and influence on l-lysine formation. | although numerous bacteria possess genes annotated iol in their genomes, there have been very few studies on the possibly associated myo-inositol metabolism and its significance for the cell. we found that corynebacterium glutamicum utilizes myo-inositol as a carbon and energy source, enabling proliferation with a high maximum rate of 0.35 h-1. whole-genome dna microarray analysis revealed that 31 genes respond to myo-inositol utilization, with 21 of them being localized in two clusters of >14 k ... | 2006 | 16997948 |
| functional analysis of the twin-arginine translocation pathway in corynebacterium glutamicum atcc 13869. | compared to those of other gram-positive bacteria, the genetic structure of the corynebacterium glutamicum tat system is unique in that it contains the tate gene in addition to tata, tatb, and tatc. the tate homologue has been detected only in the genomes of gram-negative enterobacteria. to assess the function of the c. glutamicum tat pathway, we cloned the tata, tatb, tatc, and tate genes from c. glutamicum atcc 13869 and constructed mutants carrying deletions of each tat gene or of both the ta ... | 2006 | 16997984 |
| an experimental comparison of respiration measuring techniques in fermenters and shake flasks: exhaust gas analyzer vs. ramos device vs. respirometer. | respiration measurement is applied as a universal tool to determine the activity of biological systems. the measurement techniques are difficult to compare, due to the vast variety of devices and analytical procedures commonly in use. they are used in fields as different as microbiology, gene engineering, toxicology, and industrial process monitoring to observe the physiological activity of living systems in environments as diverse as fermenters, shake flasks, lakes and sewage plants. a method i ... | 2007 | 17001475 |
| genes from a dietzia sp. for synthesis of c40 and c50 beta-cyclic carotenoids. | dietzia sp. cq4 accumulated the c(40) beta-cyclic carotenoids (canthaxanthin and echinenone) and the c(50) beta-cyclic carotenoid (c.p.450 monoglucoside). a plant-type lycopene beta-cyclase gene crtl was identified for beta-cyclization of the c(40) carotenoids. a carotenoid synthesis gene cluster was identified away from the crtl gene, which contained the crtebi genes for the synthesis of lycopene followed by the lbtabc genes for lycopene elongation and beta-cyclization of the c(50) carotenoids. ... | 2007 | 17008032 |
| quantification of cell size distribution as applied to the growth of corynebacterium glutamicum. | it is known that the cell size is related to the physiological state of a cell. therefore, cell size distribution directly reflects the average physiological properties of the cell culture. cell size distribution can be enumerated by image analysis, flow cytometry and coulter counter. in this study, image analysis was used to characterize the cell size distribution during the growth of corynebacterium glutamicum and was further analyzed by a distribution function. the parameters of the distribut ... | 2008 | 17008078 |
| metabolic pathways and biotechnological production of l-cysteine. | l-cysteine is an important amino acid both biologically and commercially. although most amino acids are commercially produced by fermentation, cysteine is mainly produced by protein hydrolysis. however, synthetic or biotechnological products have been preferred in the market. biotechnological processes for cysteine production, both enzymatic and fermentative processes, are discussed. enzymatic process, the asymmetric hydrolysis of dl-2-amino-delta(2)-thiazoline-4-carboxylic acid to l-cysteine, h ... | 2006 | 17021879 |
| understanding the roadmap of metabolism by pathway analysis. | the theoretical investigation of the structure of metabolic systems has recently attracted increasing interest. in this chapter, the basic concepts of metabolic pathway analysis are described and various applications are outlined. in particular, the concepts of nullspace and elementary flux modes are explained. the presentation is illustrated by a simple example from tyrosine metabolism and a system describing lysine production in corynebacterium glutamicum. the latter system gives rise to 37 el ... | 2007 | 17035688 |
| analysis of optimal phenotypic space using elementary modes as applied to corynebacterium glutamicum. | quantification of the metabolic network of an organism offers insights into possible ways of developing mutant strain for better productivity of an extracellular metabolite. the first step in this quantification is the enumeration of stoichiometries of all reactions occurring in a metabolic network. the structural details of the network in combination with experimentally observed accumulation rates of external metabolites can yield flux distribution at steady state. one such methodology for quan ... | 2006 | 17038164 |
| production system for biodegradable polyester polyhydroxybutyrate by corynebacterium glutamicum. | a biosynthetic pathway for poly(3-hydroxybutyrate) [p(3hb)] production by corynebacterium glutamicum was developed by introducing the phbcab operon derived from ralstonia eutropha. p(3hb) synthase activity was detected in this recombinant c. glutamicum carrying a cell surface protein gene promoter. intracellular p(3hb) was microscopically observed as inclusion granules and its content was calculated to be 22.5% (w/w) with a number average molecular weight of 2.1x10(5) and a polydispersity of 1.6 ... | 2006 | 17046539 |
| two-chamber afm: probing membrane proteins separating two aqueous compartments. | biological membranes compartmentalize and define physical borders of cells. they are crowded with membrane proteins that fulfill diverse crucial functions. about one-third of all genes in organisms code for, and the majority of drugs target, membrane proteins. to combine structure and function analysis of membrane proteins, we designed a two-chamber atomic force microscopy (afm) setup that allows investigation of membranes spanned over nanowells, therefore separating two aqueous chambers. we ima ... | 2006 | 17060909 |
| corynebacterium glutamicum as a model bacterium for the bioremediation of arsenic. | arsenic is an extremely toxic metalloid that, when present in high concentrations, severely threatens the biota and human health. arsenic contamination of soil, water, and air is a global growing environmental problem due to leaching from geological formations, the burning of fossil fuels, wastes generated by the gold mining industry present in uncontrolled landfills, and improper agriculture or medical uses. unlike organic contaminants, which are degraded into harmless chemical species, metals ... | 2006 | 17061211 |
| evidence for activator and repressor functions of the response regulator mtra from corynebacterium glutamicum. | previous analysis of a corynebacterium glutamicum delta mtrab mutant showed that the mtrab two-component signal transduction system influences the expression of genes involved in cell wall metabolism or osmoregulation, but it remained unknown whether this influence is direct or indirect. in order to identify the direct target genes of the response regulator mtra, chromatin immunoprecipitation as a genome-wide approach and dna affinity chromatography as a gene-specific approach were used. the res ... | 2006 | 17064374 |
| crystallization and initial crystallographic characterization of the corynebacterium glutamicum nitrilotriacetate monooxygenase component a. | safety and environmental concerns have recently dictated the proper disposal of nitrilotriacetate (nta). biodegradation of nta is initiated by nta monooxygenase, which is composed of two proteins: component a and component b. the nta monooxygenase component a protein from corynebacterium glutamicum was crystallized using the sitting-drop vapour-diffusion method in the presence of ammonium sulfate as the precipitant. x-ray diffraction data were collected to a maximum resolution of 2.5 a on a sync ... | 2006 | 17077499 |
| analysis of subcellular surface structure, function and dynamics. | analytics of single biological cells allows quantitative investigation from a structural, functional and dynamical point of view and opens novel possibilities to an unamplified subcellular analysis. in this article, we report on three different experimental methods and their applications to single cellular systems with a subcellular sensitivity down to the single molecule level. first, the subcellular surface structure of living bacteria (corynebacterium glutamicum) was investigated with atomic ... | 2007 | 17082883 |
| topology and mutational analysis of the single emb arabinofuranosyltransferase of corynebacterium glutamicum as a model of emb proteins of mycobacterium tuberculosis. | the cell wall mycolyl-arabinogalactan (ag)--peptidoglycan complex is essential in mycobacterial species, such as mycobacterium tuberculosis, and is the target of several antitubercular drugs. for instance, ethambutol (emb) targets ag biosynthesis through inhibition of the arabinofuranosyltransferases mt-emba and mt-embb, as well as the single emb from corynebacterium glutamicum. here, we present for the first time an experimental analysis of the membrane topology of emb. the domain organization ... | 2007 | 17088267 |
| disruption of malate:quinone oxidoreductase increases l-lysine production by corynebacterium glutamicum. | genomic analysis of a classically derived l-lysine-producing mutant, corynebacterium glutamicum b-6, identified a nonsense mutation in the mqo gene, which encodes malate:quinone oxidoreductase (mqo). the effect of mqo disruption on l-lysine production was investigated in a defined l-lysine producer, c. glutamicum ahp-3, showing approximately 18% increased production. to explore the underlying mechanisms of the increase, the mqo-disrupted strain was analyzed from the viewpoints of redox balance, ... | 2006 | 17090916 |
| multiple gene duplication and rapid evolution in the groel gene: functional implications. | the chaperonins, groel and groes, are present ubiquitously and provide a paradigm in the understanding of assisted protein folding. due to its essentiality of function, groel exhibits high sequence conservation across species. complete genome sequencing has shown the occurrence of duplicate or multiple copies of groel genes in bacteria such as mycobacterium tuberculosis and corynebacterium glutamicum. monophyly of each bacterial clade in the phylogenetic tree generated for the groel protein sugg ... | 2006 | 17103057 |
| ramb, the transcriptional regulator of acetate metabolism in corynebacterium glutamicum, is subject to regulation by rama and ramb. | in corynebacterium glutamicum, the transcriptional regulator ramb negatively controls the expression of genes involved in acetate metabolism. here we show that ramb represses its own expression by direct interaction with a 13-bp motif in the ramb promoter region. additionally, ramb expression is subject to carbon source-dependent positive control by rama. | 2007 | 17114251 |
| role of cytochrome bd oxidase from corynebacterium glutamicum in growth and lysine production. | corynebacterium glutamicum possesses two terminal oxidases, cytochrome aa3 and cytochrome bd. cytochrome aa3 forms a supercomplex with the cytochrome bc1 complex, which contains an unusual diheme cytochrome c1. both the bc1 -aa3 supercomplex and cytochrome bd transfer reducing equivalents from menaquinol to oxygen; however, they differ in their proton translocation efficiency by a factor of three. here, we analyzed the role of cytochrome bd for growth and lysine production. when cultivated in gl ... | 2007 | 17142369 |
| reduced folate supply as a key to enhanced l-serine production by corynebacterium glutamicum. | the amino acid l-serine is required for pharmaceutical purposes, and the availability of a sugar-based microbial process for its production is desirable. however, a number of intracellular utilization routes prevent overproduction of l-serine, with the essential serine hydroxymethyltransferase (shmt) (glya) probably occupying a key position. we found that constructs of corynebacterium glutamicum strains where chromosomal glya expression is dependent on ptac and laciq are unstable, acquiring muta ... | 2007 | 17142381 |
| seed-specific expression of a bacterial phosphoenolpyruvate carboxylase in vicia narbonensis increases protein content and improves carbon economy. | an ambitious aim in plant breeding and biotechnology is to increase the protein content of crop seeds used for food and feed. using an approach to manipulate assimilate partitioning, we succeeded in elevating the protein content in legume seeds up to 50%. transgenic bean plants were generated which express a corynebacterium glutamicum phosphoenolpyruvate carboxylase (pepc) in a seed-specific manner. the bacterial enzyme was not feedback inhibited by malate. transgenic seeds showed a higher [14c] ... | 2004 | 17147612 |
| characterization of a unique mutant lyse gene, originating from corynebacterium glutamicum, encoding a product that induces l-lysine production in methylophilus methylotrophus. | lyse24 is an allele of lyse encoding an l-lysine exporter of corynebacterium glutamicum. the mutant gene is able to induce l-lysine production in methylophilus methylotrophus. although lyse24 has a mutation in the middle of lyse that results in chain termination, the entire lyse locus, including the region downstream of the short open reading frame, is necessary for l-lysine production. we propose that separate polypeptides are synthesized from the lyse24 locus due to reinitiation of translation ... | 2006 | 17151474 |
| altered metabolic flux due to deletion of odha causes l-glutamate overproduction in corynebacterium glutamicum. | l-glutamate overproduction in corynebacterium glutamicum, a biotin auxotroph, is induced by biotin limitation or by treatment with certain fatty acid ester surfactants or with penicillin. we have analyzed the relationship between the inductions, 2-oxoglutarate dehydrogenase complex (odhc) activity, and l-glutamate production. here we show that a strain deleted for odha and completely lacking odhc activity produces l-glutamate as efficiently as the induced wild type (27.8 mmol/g [dry weight] of c ... | 2007 | 17158630 |
| detection and identification of bacteria using antibiotic susceptibility and a multi-array electrochemical sensor with pattern recognition. | this work proposes the use of amperometric signals generated by a 96-well multi-array dissolved oxygen multi-electrode sensor (dox) coupled with principal component analysis for continuous monitoring, identification and differentiation of bacteria. two types of differentiation mechanisms were tested: (1) direct monitoring of respiratory activity via oxygen consumption and (2) quantification of the effect of three broad-spectrum antibiotics on bacteria growth and respiration over time. five speci ... | 2007 | 17169547 |
| inactivation of corynebacterium glutamicum ncgl0452 and the role of mgta in the biosynthesis of a novel mannosylated glycolipid involved in lipomannan biosynthesis. | mycobacterium tuberculosis pimb has been demonstrated to catalyze the addition of a mannose residue from gdp-mannose to a monoacylated phosphatidyl-myo-inositol mannoside (ac(1)pim(1)) to generate ac(1)pim(2). herein, we describe the disruption of its probable orthologue cg-pimb and the chemical analysis of glycolipids and lipoglycans isolated from wild type corynebacterium glutamicum and the c. glutamicum::pimb mutant. following a careful analysis, two related glycolipids, gl-a and gl-x, were f ... | 2007 | 17179146 |
| the phosphotransferase system of corynebacterium glutamicum: features of sugar transport and carbon regulation. | in this review, we describe the phosphotransferase system (pts) of corynebacterium glutamicum and discuss genes for putative global carbon regulation associated with the pts. c. glutamicum atcc 13032 has pts genes encoding the general phosphotransferases enzyme i, hpr and four enzyme ii permeases, specific for glucose, fructose, sucrose and one yet unknown substrate. c. gluamicum has a peculiar sugar transport system involving fructose efflux after hydrolyzing sucrose transported via sucrose eii ... | 2007 | 17183210 |
| rama, the transcriptional regulator of acetate metabolism in corynebacterium glutamicum, is subject to negative autoregulation. | the rama protein represents a luxr-type transcriptional activator of genes involved in acetate metabolism of corynebacterium glutamicum. here we analyze the expression of the respective rama gene and its regulation. transcription was found to start 71 nucleotides upstream of the translational start codon and to be two- to threefold up-regulated in the presence of acetate in the growth medium. accordingly, about twofold higher amounts of rama were observed in c. glutamicum cells grown on acetate ... | 2007 | 17183211 |
| nitrogen metabolism and nitrogen control in corynebacteria: variations of a common theme. | the published genome sequences of corynebacterium diphtheriae, corynebacterium efficiens, corynebacterium glutamicum and corynebacterium jeikeium were screened for genes encoding central components of nitrogen source uptake, nitrogen assimilation and nitrogen control systems. interestingly, the soil-living species c. efficiens and c. glutamicum exhibit a broader spectrum of genes for nitrogen transport and metabolism than the pathogenic species c. diphtheriae and c. jeikeium. the latter are char ... | 2007 | 17183220 |
| transcriptional regulation of catabolic pathways for aromatic compounds in corynebacterium glutamicum. | corynebacterium glutamicum is a gram-positive soil microorganism able to utilize a large variety of aromatic compounds as the sole carbon source. the corresponding catabolic routes are associated with multiple ring-fission dioxygenases and among other channeling reactions, include the gentisate pathway, the protocatechuate and catechol branches of the beta-ketoadipate pathway and two potential hydroxyquinol pathways. genes encoding the enzymatic machinery for the bioconversion of aromatic compou ... | 2006 | 17183485 |
| precise metabolic flux analysis of coryneform bacteria by gas chromatography-mass spectrometry and verification by nuclear magnetic resonance. | precise metabolic flux analysis (mfa) by gas chromatography-mass spectrometry (gc-ms) and computer calculation was performed, and the consistency of the estimated results was verified by independently performed nuclear magnetic resonance (nmr) analysis. the precise estimation of flux by the integration method of the mass isotopomer signal, defined as the coefficient of variance (cv) of multiple determination, was investigated, and the results estimated using different data sets with the same mag ... | 2006 | 17189168 |
| secrets of soil survival revealed by the genome sequence of arthrobacter aurescens tc1. | arthrobacter sp. strains are among the most frequently isolated, indigenous, aerobic bacterial genera found in soils. member of the genus are metabolically and ecologically diverse and have the ability to survive in environmentally harsh conditions for extended periods of time. the genome of arthrobacter aurescens strain tc1, which was originally isolated from soil at an atrazine spill site, is composed of a single 4,597,686 basepair (bp) circular chromosome and two circular plasmids, ptc1 and p ... | 2006 | 17194220 |
| the alternative sigma factor sigb of corynebacterium glutamicum modulates global gene expression during transition from exponential growth to stationary phase. | corynebacterium glutamicum is a gram-positive soil bacterium widely used for the industrial production of amino acids. there is great interest in the examination of the molecular mechanism of transcription control. one of these control mechanisms are sigma factors. c. glutamicum atcc 13032 has seven putative sigma factor-encoding genes, including siga and sigb. the siga gene encodes the essential primary sigma factor of c. glutamicum and is responsible for promoter recognition of house-keeping g ... | 2007 | 17204139 |
| expression of the escherichia coli pntab genes encoding a membrane-bound transhydrogenase in corynebacterium glutamicum improves l-lysine formation. | a critical factor in the biotechnological production of l: -lysine with corynebacterium glutamicum is the sufficient supply of nadph. the membrane-integral nicotinamide nucleotide transhydrogenase pntab of escherichia coli can use the electrochemical proton gradient across the cytoplasmic membrane to drive the reduction of nadp(+) via the oxidation of nadh. as c. glutamicum does not possess such an enzyme, we expressed the e. coli pntab genes in the genetically defined c. glutamicum lysine-produ ... | 2007 | 17216441 |
| production of l-lysine from starch by corynebacterium glutamicum displaying alpha-amylase on its cell surface. | we engineered a corynebacterium glutamicum strain displaying alpha-amylase from streptococcus bovis 148 (amya) on its cell surface to produce amino acids directly from starch. we used pgsa from bacillus subtilis as an anchor protein, and the n-terminus of alpha-amylase was fused to the pgsa. the genes of the fusion protein were integrated into the homoserine dehydrogenase gene locus on the chromosome by homologous recombination. l-lysine fermentation was carried out using c. glutamicum displayin ... | 2007 | 17216452 |
| random segment deletion based on is31831 and cre/loxp excision system in corynebacterium glutamicum. | a simple and random genome deletion method combining insertion sequence (is) element is31831 and the cre/loxp excision system generated 42 corynebacterium glutamicum mutants (0.2-186 kb). a total of 393.6 kb (11.9% of c. glutamicum r genome) coding for 331 genes was confirmed to be nonessential under standard laboratory conditions. the deletion strains, generated using only two vectors, varied not only in their lengths but also the location of the deletion along the c. glutamicum r genome. by co ... | 2007 | 17221197 |