Publications

TitleAbstractYear
Filter
PMID(sorted ascending)
Filter
the effect of argr-dna binding affinity on ornithine production in corynebacterium glutamicum.pembtl-sy1, which can over produce the argr protein in corynebacterium glutamicum, was constructed. the dna-binding affinity of argr was analyzed using a chromatin immunoprecipitation (chip) assay. the level of argr protein expression in the plasmid-carrying c. glutamicum (pembtl-sy1) was higher than that in the wild-type strain. on the other hand, there was no increase in the dna-binding affinity of argr on the upstream of argb and the level of ornithine production. the dna-binding affinity of ...200919688381
reinforcement of carboxyl groups in the surface of corynebacterium glutamicum biomass for effective removal of basic dyes.the biomass of corynebacterium glutamicum was treated with poly(amic acid) to improve the biosorption of basic blue 3 (bb3) from aqueous solution. the grafting of poly(amic acid) onto the biomass surface increased the density of the carboxyl groups. the uv-spectrum revealed that strong acidic (ph2) and basic conditions (ph11) resulted in the precipitation of bb3. therefore, ph edge experiments were conducted only within the range 3-10; these results indicated that electrostatic attraction betwee ...200919692228
visualizing post genomics data-sets on customized pathway maps by prometra-aeration-dependent gene expression and metabolism of corynebacterium glutamicum as an example.the rapid progress of post-genomic analyses, such as transcriptomics, proteomics, and metabolomics has resulted in the generation of large amounts of quantitative data covering and connecting the complete cascade from genotype to phenotype for individual organisms. various benefits can be achieved when these "omics" data are integrated, such as the identification of unknown gene functions or the elucidation of regulatory networks of whole organisms. in order to be able to obtain deeper insights ...200919698148
optical device for parallel online measurement of dissolved oxygen and ph in shake flask cultures.we describe a new device with parallel optical measurement of dissolved oxygen (do) and ph in up to nine shake flasks applicable in any conventional shaking incubator. measurement ranges are 0-500% of air saturation for oxygen and 5.5-8.5 for ph. it was used to characterize growth profiles of different l-lysine producing strains of corynebacterium glutamicum, of saccharomyces cerevisiae and of escherichia coli. cultures in unbaffled flasks were highly reproducible. oxygen limitation was indicate ...201019701780
conversion of phenol to glutamate and proline in corynebacterium glutamicum is regulated by transcriptional regulator argr.this paper reports a novel integrated metabolic pathway of amino acid production through the utilization of phenol in corynebacterium glutamicum. in the presence of 8.5 mm phenol, the level of glutamate and proline production increased up to 1.2- and 14.7-fold, respectively, compared to the control condition. in addition, their productivities increased 1.6- and 20-fold in the culture medium using phenol as the sole carbon source with 72 microm feso(4) as iron supplementation. chromatin immunopre ...201019707750
electron paramagnetic resonance (epr) spectroscopy of the stable-free radical in the native metallo-cofactor of the manganese-ribonucleotide reductase (mn-rnr) of corynebacterium glutamicum.ribonucleotide reductases (rnr; ec 1.17.4.1) provide the 2'-deoxyribonucleotides for dna replication of proliferating cells by a uniform radical mechanism using diverse metals. the native metallo-cofactor of the corynebacterium glutamicum rnr contains manganese and is sensitive to edta and radical scavengers. hybrid holoenzymes, capable of ribonucleotide reduction, were composed of the small manganese-containing (r2f) and the large catalytic subunit (r1e) from either of the two corynebacterial r ...200919707921
the benefit of combining nlc-maldi-orbitrap ms data with nlc-maldi-tof/tof data for proteomic analyses employing elastase.the recently established coupling of a maldi-type ion source to a linear ion trap and an orbitrap mass analyzer offers high-accuracy mass measurements compared to common maldi-tof/tof instruments. contrary to maldi-tof/tof, the fragmentation of peptides in the new hybrid mass spectrometer is less efficient due to the generation of predominantly singly charged ions by the maldi process. therefore, data from two maldi instruments, tof/tof and orbitrap, were combined into a single data set in order ...200919725589
display of alpha-amylase on the surface of corynebacterium glutamicum cells by using ncgl1221 as the anchoring protein, and production of glutamate from starch.we developed a new cell surface display system in corynebacterium glutamicum based on the c-terminally truncated ncgl1221 anchor protein to increase l-glutamate production from starch directly. the c-terminally truncated ncgl1221 protein is a mutant ncgl1221 and leads to the constitutive export of l-glutamate. the n terminus of alpha-amylase (amya) was fused to truncated ncgl1221, and the resulting fusion protein was expressed on the cell surface by iptg induction. localization of the fusion pro ...200919727672
correlation between proton translocation and growth: genetic analysis of the respiratory chain of corynebacterium glutamicum.corynebacterium glutamicum contains at least two terminal oxidases in the respiratory chain; cytochrome aa(3)-type cytochrome c oxidase and bd-type menaquinol oxidase. thus, the chain has two branches of electron flow. the bcc-aa(3) branch translocates three protons per electron transferred, while the bd branch translocates only one. in this study, we constructed two mutant strains, lacking of either subunit i of the cytochrome c oxidase (deltactad) or subunits i and ii of the quinol oxidase (de ...200919734178
role of the transcriptional regulator ramb (rv0465c) in the control of the glyoxylate cycle in mycobacterium tuberculosis.mycobacterium tuberculosis generally is assumed to depend on lipids as a major carbon and energy source when persisting within the host. the utilization of fatty acids requires a functional glyoxylate cycle with the key enzymes isocitrate lyase (icl) and malate synthase. the open reading frame rv0465c of m. tuberculosis h37rv encodes a protein with significant sequence similarity to the transcriptional regulator ramb, which in corynebacterium glutamicum controls the expression of several genes i ...200919767422
genetic and biochemical analysis of the serine/threonine protein kinases pkna, pknb, pkng and pknl of corynebacterium glutamicum: evidence for non-essentiality and for phosphorylation of odhi and ftsz by multiple kinases.we previously showed that the 2-oxoglutarate dehydrogenase inhibitor protein odhi of corynebacterium glutamicum is phosphorylated by pkng at thr14, but that also additional serine/threonine protein kinases (stpks) can phosphorylate odhi. to identify these, a set of three single (deltapkna, deltapknb, deltapknl), five double (deltapknag, deltapknal, deltapknbg, deltapknbl, deltapknlg) and two triple deletion mutants (deltapknalg, deltapknblg) were constructed. the existence of these mutants shows ...200919788543
computing the shortest elementary flux modes in genome-scale metabolic networks.elementary flux modes (efms) represent a key concept to analyze metabolic networks from a pathway-oriented perspective. in spite of considerable work in this field, the computation of the full set of elementary flux modes in large-scale metabolic networks still constitutes a challenging issue due to its underlying combinatorial complexity.200919793869
proline reduces the binding of transcriptional regulator argr to upstream of argb in corynebacterium glutamicum.in this study, the argr-binding sites on the arg operon corynbebacterium glutamicum were characterized by in vivo chromatin immunoprecipitation (chip). in addition, the argr-binding affinity in the presence of glutamate, proline, or arginine was examined to get further information on expression control. the chip assay showed that the argr protein binds specifically to the upstream regions of argc, argb, argf, and argg. upon proline supplementation, argr-binding affinity was significantly reduced ...201019798496
identification of a stress-induced factor of corynebacterineae that is involved in the regulation of the outer membrane lipid composition.corynebacterineae are gram-positive bacteria that possess a true outer membrane composed of mycolic acids and other lipids. little is known concerning the modulation of mycolic acid composition and content in response to changes in the bacterial environment, especially temperature variations. to address this question, we investigated the function of the rv3802c gene, a gene conserved in corynebacterineae and located within a gene cluster involved in mycolic acid biosynthesis. we showed that the ...200919801408
qupe--a rich internet application to take a step forward in the analysis of mass spectrometry-based quantitative proteomics experiments.the goal of present -omics sciences is to understand biological systems as a whole in terms of interactions of the individual cellular components. one of the main building blocks in this field of study is proteomics where tandem mass spectrometry (lc-ms/ms) in combination with isotopic labelling techniques provides a common way to obtain a direct insight into regulation at the protein level. methods to identify and quantify the peptides contained in a sample are well established, and their outpu ...200919808875
the corynebacterium glutamicum ncgl2281 gene encoding an rnase e/g family endoribonuclease can complement the escherichia coli rng::cat mutation but not the rne-1 mutation.the corynebacterium glutamicum ncgl2281 gene encodes an rnase e/g family endoribonuclease having an additional n-terminal domain of unknown function. in this study, we constructed plasmids expressing the full length (fl) and the n-terminally truncated form (deltan) of ncgl2281 and examined their complementation ability as to escherichia coli rng::cat and rne-1 mutations. both fl- and deltan-ncgl2281 rescued the defects caused by the rng::cat mutation, i.e., accumulation of 16s rrna precursor, ov ...200919809192
metabolic engineering of the tricarboxylic acid cycle for improved lysine production by corynebacterium glutamicum.in the present work, lysine production by corynebacterium glutamicum was improved by metabolic engineering of the tricarboxylic acid (tca) cycle. the 70% decreased activity of isocitrate dehydrogenase, achieved by start codon exchange, resulted in a >40% improved lysine production. by flux analysis, this could be correlated to a flux shift from the tca cycle toward anaplerotic carboxylation.200919820141
biotechnological production of enantiomeric pure lactic acid from renewable resources: recent achievements, perspectives, and limits.lactic acid (la) is an important and versatile chemical that can be produced from renewable resources such as biomass. la is used in the food, pharmaceutical, and polymers industries and is produced by microorganism fermentation; however, most microorganisms cannot directly utilize biomass such as starchy materials and cellulose. here, we summarize la production using several kinds of genetically modified microorganisms, such as la bacteria, escherichia coli, corynebacterium glutamicum, and yeas ...201019826806
sugar transporters in efficient utilization of mixed sugar substrates: current knowledge and outlook.there is increasing interest in production of transportation fuels and commodity chemicals from lignocellulosic biomass, most desirably through biological fermentation. considerable effort has been expended to develop efficient biocatalysts that convert sugars derived from lignocellulose directly to value-added products. glucose, the building block of cellulose, is the most suitable fermentation substrate for industrial microorganisms such as escherichia coli, corynebacterium glutamicum, and sac ...201019838697
[cloning and analysis of promoter-active fragments from corynebacterium glutamicum 10147].to clone promoter-active fragments from corynebacterium glutamicum for further construction of expression vectors.200919873765
increased glucose utilization in corynebacterium glutamicum by use of maltose, and its application for the improvement of l-valine productivity.corynebacterium glutamicum efficiently utilizes maltose as a substrate. we show here that the presence of maltose increases glucose utilization by raising the expression of ptsg, which encodes the glucose-specific eii permease of the phosphotransferase system. consequently, the l-valine productivity of a pyruvate dehydrogenase complex-deficient c. glutamicum strain was improved by the presence of maltose.201019880641
crystallization and preliminary crystallographic analysis of the global nitrogen regulator amtr from corynebacterium glutamicum.amtr, a member of the tetr family of transcription regulators, is a global regulator of nitrogen control in corynebacterium glutamicum. unlike other tetr-family members, which are regulated by small-molecule effectors, amtr is regulated by a protein called glnk. it has been shown that a glnk trimer has to become adenylylated prior to formation of a complex with amtr. the physiological function of amtr has been very well studied, but structural characterization of the mechanistic aspects of amtr- ...200919923732
disulfide bond formation and cysteine exclusion in gram-positive bacteria.most secretion pathways in bacteria and eukaryotic cells are challenged by the requirement for their substrate proteins to mature after they traverse a membrane barrier and enter a reactive oxidizing environment. for gram-positive bacteria, the mechanisms that protect their exported proteins from misoxidation during their post-translocation maturation are poorly understood. to address this, we separated numerous bacterial species according to their tolerance for oxygen and divided their proteome ...201019940132
adaptation of corynebacterium glutamicum to salt-stress conditions.corynebacterium glutamicum is one of the biotechnologically most important microorganisms because of its ability to enrich amino acids extracellularly. hence, c. glutamicum requires effective adaptation strategies against both hypo- and hyperosmotic stress. we give a comprehensive and coherent outline about the quantitative dynamics of c. glutamicum during adaptation to hyperosmotic stress at the transcript and protein levels. the osmolyte carrier prop, playing a pivotal role in hyperosmotic str ...201019950167
requirement of de novo synthesis of the odhi protein in penicillin-induced glutamate production by corynebacterium glutamicum.we found that penicillin-induced glutamate production by corynebacterium glutamicum is inhibited when a de novo protein synthesis inhibitor, chloramphenicol, is added simultaneously with penicillin. when chloramphenicol was added 4 h after penicillin addition, glutamate production was essentially unaffected. (3)h-leucine incorporation experiments revealed that protein synthesis continued for 1 h after penicillin addition and then gradually decreased. these results suggest that de novo protein sy ...201019956942
microbial production host selection for converting second-generation feedstocks into bioproducts.increasingly lignocellulosic biomass hydrolysates are used as the feedstock for industrial fermentations. these biomass hydrolysates are complex mixtures of different fermentable sugars, but also inhibitors and salts that affect the performance of the microbial production host. the performance of six industrially relevant microorganisms, i.e. two bacteria (escherichia coli and corynebacterium glutamicum), two yeasts (saccharomyces cerevisiae and pichia stipitis) and two fungi (aspergillus niger ...200919958560
impact of adenylyltransferase glne on nitrogen starvation response in corynebacterium glutamicum.adenylyltransferases regulate glutamine synthetase activity in enterobacteria and actinomycetes such as streptomyces coelicolor, mycobacterium tuberculosis and corynebacterium glutamicum. in this study the effects of a mutation of the glne gene, coding for adenylyltransferase, on transcriptome and metabolome profiles of c. glutamicum was investigated. as expected, the glne deletion led to a loss of activity regulation of glutamine synthetase. astonishingly, additionally the glne mutation caused ...201019963018
the transcriptional regulatory repertoire of corynebacterium glutamicum: reconstruction of the network controlling pathways involved in lysine and glutamate production.corynebacterium glutamicum is one of the best studied organisms of the high g+c branch of gram-positive bacteria and an emerging model system for the suborder corynebacterineae. to gain insights into the regulatory gene composition and architecture of the transcriptional regulatory network of c. glutamicum, components of the transcriptional regulatory repertoire were intensively studied by many scientific groups in recent years. in this mini-review, we summarize the present knowledge about the d ...201019963020
reconstitution experiments and gene deletions reveal the existence of two-component major cell wall channels in the genus corynebacterium.two small polypeptides, pora and porh, are known to form cell wall channels in corynebacterium glutamicum and in corynebacterium efficiens. the genes coding for both polypeptides are localized in close proximity to one another between the genes coding for groel2 and a polyphosphate kinase (pkk2). in this study, we investigated the relationship of pora and porh to one another. the results suggested that the major cell wall channels of corynebacterium glutamicum, corynebacterium efficiens, and cor ...201019966008
elucidation of genes relevant to the microaerobic growth of corynebacterium glutamicum.mutagenized cell libraries of corynebacterium glutamicum were screened for mutants that lost the ability to grow under low oxygen concentrations. the resulting high-oxygen-requiring mutants were used to clone wild-type dna fragments that could complement the phenotype. sequencing and subcloning analyses identified six genes, cgl0807, cgl1102, cgl0600, cgl1427, cgl2857, and cgl2859, as the genes responsible for complementation. some of these genes showed cross-complementation of the mutants in ox ...200919966452
isolation, evaluation and use of two strong, carbon source-inducible promoters from corynebacterium glutamicum.to obtain strong, carbon source-inducible promoters useful for industrial applications of corynebacterium glutamicum.201020002569
retention of arsenate using genetically modified coryneform bacteria and determination of arsenic in solid samples by icp-ms.a novel method for the retention of arsenate [as(v)] combining time-controlled solid-phase extraction with living bacterial biomass is presented. as(v) retention was carried out by exposing the extractant, consisting of a living double-mutant of corynebacterium glutamicum strain arsc1-c2, to the sample for a retention time of 1-7min, before the arsenic distribution equilibrium between the sample solution and the extractant was established. the amount of as(v) retained in the biomass was measured ...201020006108
xylitol production by recombinant corynebacterium glutamicum under oxygen deprivation.wild-type corynebacterium glutamicum produced 0.6 g l(-1) xylitol from xylose at a productivity of 0.01 g l(-1) h(-1) under oxygen deprivation. to increase this productivity, the pentose transporter gene (arae) from c. glutamicum atcc31831 was integrated into the c. glutamicum r chromosome. consequent disruption of its lactate dehydrogenase gene (ldha), and expression of single-site mutant xylose reductase from candida tenuis (ctxr (k274r)) resulted in recombinant c. glutamicum strain ctxr4 that ...201020012280
analysing overexpression of l-valine biosynthesis genes in pyruvate-dehydrogenase-deficient corynebacterium glutamicum.l-valine biosynthesis was analysed by comparing different plasmids in pyruvate-dehydrogenase-deficient corynebacterium glutamicum strains in order to achieve an optimal production strain. the plasmids contained different combinations of the genes ilvbncde encoding for the l-valine forming pathway. it was shown that overexpression of the ilvbn genes encoding acetolactate synthase is obligatory for efficient pyruvate conversion and to prevent l-alanine as a by-product. in contrast to earlier studi ...201020012552
importance of nadph supply for improved l-valine formation in corynebacterium glutamicum.cofactor recycling is known to be crucial for amino acid synthesis. hence, cofactor supply was now analyzed for l-valine to identify new targets for an improvement of production. the central carbon metabolism was analyzed by stoichiometric modeling to estimate the influence of cofactors and to quantify the theoretical yield of l-valine on glucose. three different optimal routes for l-valine biosynthesis were identified by elementary mode (em) analysis. the modes differed mainly in the manner of ...201020014412
functional genomics of ph homeostasis in corynebacterium glutamicum revealed novel links between ph response, oxidative stress, iron homeostasis and methionine synthesis.the maintenance of internal ph in bacterial cells is challenged by natural stress conditions, during host infection or in biotechnological production processes. comprehensive transcriptomic and proteomic analyses has been conducted in several bacterial model systems, yet questions remain as to the mechanisms of ph homeostasis.200920025733
flux design: in silico design of cell factories based on correlation of pathway fluxes to desired properties.the identification of genetic target genes is a key step for rational engineering of production strains towards bio-based chemicals, fuels or therapeutics. this is often a difficult task, because superior production performance typically requires a combination of multiple targets, whereby the complex metabolic networks complicate straightforward identification. recent attempts towards target prediction mainly focus on the prediction of gene deletion targets and therefore can cover only a part of ...200920035624
the zur regulon of corynebacterium glutamicum atcc 13032.zinc is considered as an essential element for all living organisms, but it can be toxic at large concentrations. bacteria therefore tightly regulate zinc metabolism. the cg2502 protein of corynebacterium glutamicum was a candidate to control zinc metabolism in this species, since it was classified as metalloregulator of the zinc uptake regulator (zur) subgroup of the ferric uptake regulator (fur) family of dna-binding transcription regulators.201020055984
the transcriptional regulators rama and ramb are involved in the regulation of glycogen synthesis in corynebacterium glutamicum.when grown in glucose-, fructose- or sucrose-containing medium, the amino acid producer corynebacterium glutamicum transiently accumulates large amounts of glycogen (up to 10% of its dry weight), whereas only a marginal amount of glycogen is formed during growth with acetate. this carbon-source-dependent regulation is at least partially due to transcriptional control of glgc, encoding adp-glucose pyrophosphorylase, the first enzyme of glycogen synthesis from glucose-1-phosphate. here, we have an ...201020056699
metabolic flux estimation using particle swarm optimization with penalty function.metabolic flux estimation through 13c trace experiment is crucial for quantifying the intracellular metabolic fluxes. in fact, it corresponds to a constrained optimization problem that minimizes a weighted distance between measured and simulated results. in this paper, we propose particle swarm optimization (pso) with penalty function to solve 13c-based metabolic flux estimation problem. the stoichiometric constraints are transformed to an unconstrained one, by penalizing the constraints and bui ...200920077391
pcao positively regulates pcahg of the beta-ketoadipate pathway in corynebacterium glutamicum.we identified a new regulator, pcao, which is involved in regulation of the protocatechuate (pca) branch of the beta-ketoadipate pathway in corynebacterium glutamicum. pcao is an atypical large atp-binding luxr family (lal)-type regulator and does not have a walker a motif. a mutant of c. glutamicum in which pcao was disrupted (res167deltapcao) was unable to grow on pca, and growth on pca was restored by complementation with pcao. both an enzymatic assay of pca 3,4-dioxygenase activity (encoded ...201020081038
the regulator rama influences cmyta transcription and cell morphology of corynebacterium ammoniagenes.rama plays a regulatory role for acetate utilization and s-layer biosynthesis in corynebacterium glutamicum. looking for any additional role, the function of rama was analyzed in corynebacterium ammoniagenes, which is closely related to c. glutamicum. in this study, we showed that the deltarama mutant constructed by a markerless knockout strategy possessed increased cell surface hydrophobicity, leading to the formation of aggregated cell masses in liquid media. in addition, the mutant exhibited ...201020107993
an emergent self-organizing map based analysis pipeline for comparative metabolome studies.modern high-throughput techniques allow for the identification and quantification of hundreds of metabolites ofa biological system which cover central parts of the metabolome. due to the amount and complexity of obtained data there is an increasing need for the development of appropriate computational interpretation methods. a novel data analysis pipeline designed for high-throughput determined metabolomic data is presented. the combination of principal component analysis (pca) with emergent sel ...200920109147
a novel redox-sensing transcriptional regulator cyer controls expression of an old yellow enzyme family protein in corynebacterium glutamicum.corynebacterium glutamicum cgr_2930 (cyer) encodes a transcriptional regulator of the arsr family. its gene product, cyer, was shown here to repress the expression of cyer and the cgr_2931 (cye1)-cgr_2932 operon, which is located upstream of cyer in the opposite orientation. the cye1 gene encodes an old yellow enzyme family protein, members of which have been implicated in the oxidative stress response. cyer binds to the intergenic region between cyer and cye1. expression of cyer and cye1 is ind ...201020110293
distribution of aerobic motile and non-motile bacteria within the capillary fringe of silica sand.retention of bacterial cells as "particles" by silica sand during formation of a capillary fringe (cf) and the influence of motility was examined with motile pseudomonas putida and non-motile corynebacterium glutamicum suspensions in the absence of nutrients. the fractional retention of c. glutamicum cells at all regions of the cf was higher than for p. putida cells, most probably due to the motility of p. putida. only about 5% of p. putida cells and almost no c. glutamicum cells reached the upp ...201020116084
antimalarial and antitubercular nostocarboline and eudistomin derivatives: synthesis, in vitro and in vivo biological evaluation.the synthesis of nine nostocarboline derivatives with substitutions of the 2-methyl group by alkyl, aryl and functionalized residues, 10 symmetrical bis cationic dimers linking 6-cl-norharmane through the 2-position and fifteen derivatives of the marine alkaloids eudistomin n and o is reported. these compounds were evaluated in vitro against four parasites (trypanosoma brucei rhodesiense stib 900, trypanosoma cruzi tulahuen c2c4, leishmania donovani mhom-et-67/l82 axenic amastigotes, and plasmod ...201020133138
enhancement of ornithine production in proline-supplemented corynebacterium glutamicum by ornithine cyclodeaminase.in this study, corynebacterium glutamicum and its derived mutants were used to demonstrate the relationship between proline, glutamate and ornithine. the maximum ornithine production was shown in the culture medium (3295.0 mg/l) when the cells were cultured with 20 mm proline and was 15.5 times higher than in the presence of 1 mm proline. however, glutamate, which known as an intermediate in the process of converting proline to ornithine, did not have any positive effect on ornithine production. ...201020134243
approaching the complexity of elastase-digested membrane proteomes using off-gel ief/nlc-maldi-ms/ms.liquid chromatography, coupled with tandem mass spectrometry, is an established method for the identification of proteins from a complex sample. despite its wide application, the analysis of whole proteomes still represents a challenge to researchers, because of the complexity and dynamic range of protein concentrations in biological samples. the analysis of such samples can be improved by adding a prefractionation step or a combination of orthogonal separation techniques. off-gel isoelectric fo ...201020136094
analysis and engineering of metabolic pathway fluxes in corynebacterium glutamicum.the gram-positive soil bacterium corynebacterium glutamicum was discovered as a natural overproducer of glutamate about 50 years ago. linked to the steadily increasing economical importance of this microorganism for production of glutamate and other amino acids, the quest for efficient production strains has been an intense area of research during the past few decades. efficient production strains were created by applying classical mutagenesis and selection and especially metabolic engineering s ...201020140657
metabolic changes in a pyruvate kinase gene deletion mutant of corynebacterium glutamicum atcc 13032.to investigate primary effects of a pyruvate kinase (pyk) defect on glucose metabolism in corynebacterium glutamicum, a pyk-deleted mutant was derived from wild-type c. glutamicum atcc13032 using the double-crossover chromosome replacement technique. the mutant was then evaluated under glutamic acid-producing conditions induced by biotin limitation. the mutant showed an increased specific rate of glucose consumption, decreased growth, higher glutamic acid production, and aspartic acid formation ...201020144730
13c metabolic flux analysis for larger scale cultivation using gas chromatography-combustion-isotope ratio mass spectrometry.(13)c-based metabolic flux analysis ((13)cmfa) is limited to smaller scale experiments due to very high costs of labeled substrates. we measured (13)c enrichment in proteinogenic amino acid hydrolyzates using gas chromatography-combustion-isotope ratio mass spectrometry (gc-c-irms) from a series of parallel batch cultivations of corynebacterium glutamicum utilizing mixtures of natural glucose and [1-(13)c] glucose, containing 0%, 0.5%, 1%, 2%, and 10% [1-(13)c] glucose. decreasing the [1-(13)c] ...201020149889
polyphosphate/atp-dependent nad kinase of corynebacterium glutamicum: biochemical properties and impact of ppnk overexpression on lysine production.nicotinamide adenine dinucleotide phosphate (nadp) is synthesized by phosphorylation of either oxidized or reduced nicotinamide adenine dinucleotide (nad/nadh). here, the cg1601/ppnk gene product from corynebacterium glutamicum genome was purified from recombinant escherichia coli and enzymatic characterization revealed its activity as a polyphosphate (polyp)/atp-dependent nad kinase (ppnk). ppnk from c. glutamicum was shown to be active as homotetramer accepting polyp, atp, and even adp for pho ...201020180116
studies on substrate utilisation in l-valine-producing corynebacterium glutamicum strains deficient in pyruvate dehydrogenase complex.the pyruvate dehydrogenase complex was deleted to increase precursor availability in corynebacterium glutamicum strains overproducing l: -valine. the resulting auxotrophy is treated by adding acetate in addition glucose for growth, resulting in the puzzling fact of gluconeogenic growth with strongly reduced glucose uptake in the presence of acetate in the medium. this result was proven by intracellular metabolite analysis and labelling experiments. to increase productivity, the sugr protein invo ...201020204663
engineering of sugar metabolism of corynebacterium glutamicum for production of amino acid l-alanine under oxygen deprivation.corynebacterium glutamicum was genetically engineered to produce l-alanine from sugar under oxygen deprivation. the genes associated with production of organic acids in c. glutamicum were inactivated and the alanine dehydrogenase gene (alad) from lysinibacillus sphaericus was overexpressed to direct carbon flux from organic acids to alanine. although the alad-expressing strain produced alanine from glucose under oxygen deprivation, its productivity was relatively low due to retarded glucose cons ...201020217078
replication methods and tools in high-throughput cultivation processes - recognizing potential variations of growth and product formation by on-line monitoring.high-throughput cultivations in microtiter plates are the method of choice to express proteins from recombinant clone libraries. such processes typically include several steps, whereby some of them are linked by replication steps: transformation, plating, colony picking, preculture, main culture and induction. in this study, the effects of conventional replication methods and replication tools (8-channel pipette, 96-pin replicators: steel replicator with fixed or spring-loaded pins, plastic repl ...201020233443
genetic and functional analysis of the soluble oxaloacetate decarboxylase from corynebacterium glutamicum.soluble, divalent cation-dependent oxaloacetate decarboxylases (odx) catalyze the irreversible decarboxylation of oxaloacetate to pyruvate and co(2). although these enzymes have been characterized in different microorganisms, the genes that encode them have not been identified, and their functions have been only poorly analyzed so far. in this study, we purified a soluble odx from wild-type c. glutamicum about 65-fold and used matrix-assisted laser desorption ionization-time of flight (maldi-tof ...201020233922
transcriptional regulation of histidine biosynthesis genes in corynebacterium glutamicum.corynebacterium glutamicum, a gram-positive bacterium, has been widely used for industrial amino acid production. corynebacterium glutamicum his genes are located and transcribed in two unlinked loci, hiseg and hisdcb-orf1-orf2-hisha-impa-hisfi. the latter his operon starts the transcription at the c residue localized 196 bp upstream of the hisd atg start codon. our computer-based sequence analysis showed that the region corresponding to the untranslated 5' end of the transcript, named the hisd ...201020237580
the fha domain of odhi interacts with the carboxyterminal 2-oxoglutarate dehydrogenase domain of odha in corynebacterium glutamicum.in corynebacterium glutamicum, the unphosphorylated 15-kda odhi protein inhibits the activity of the 2-oxoglutarate dehydrogenase complex (odhc) by binding to odha, which in corynebacteria and mycobacteria is a large fusion protein with two major domains exhibiting structural features of e1o and e2 proteins. using copurification and surface plasmon resonance experiments with different odhi and odha length variants it was shown that the entire forkhead-associated (fha) domain of odhi and the c-te ...201020303957
carbohydrate metabolism in corynebacterium glutamicum and applications for the metabolic engineering of l-lysine production strains.carbohydrates exclusively serve as feedstock for industrial amino acid production with corynebacterium glutamicum. due to the industrial interest, knowledge about the pathways for carbohydrate metabolization in c. glutamicum steadily increases, enabling the rational design of optimized strains and production processes. in this review, we provide an overview of the metabolic pathways for utilization of hexoses (glucose, fructose), disaccharides (sucrose, maltose), pentoses (d-ribose, l-arabinose, ...201020333512
a deficiency in arabinogalactan biosynthesis affects corynebacterium glutamicum mycolate outer membrane stability.corynebacterineae is a specific suborder of gram-positive bacteria that includes mycobacterium tuberculosis and corynebacterium glutamicum. the ultrastructure of the cell envelope is very atypical. it is composed of a heteropolymer of peptidoglycan and arabinogalactan (ag) covalently associated to an outer membrane. five arabinosyltransferases are involved in the biosynthesis of ag in c. glutamicum. aftb catalyzes the transfer of araf (arabinofuranosyl) onto the arabinan domain of the arabinogal ...201020363942
factors enhancing l-valine production by the growth-limited l-isoleucine auxotrophic strain corynebacterium glutamicum deltailva deltapanb ilvnm13 (peckailvbnc).cell growth limitation is known to be an important condition that enhances l: -valine synthesis in corynebacterium glutamicum recombinant strains with l: -isoleucine auxotrophy. to identify whether it is the limited availability of l: -isoleucine itself or the l: -isoleucine limitation-induced rel-dependent ppgpp-mediated stringent response that is essential for the enhancement of l: -valine synthesis in growth-limited c. glutamicum cells, we deleted the rel gene, thereby constructing a relaxed ...201020364396
engineering corynebacterium glutamicum for isobutanol production.the production of isobutanol in microorganisms has recently been achieved by harnessing the highly active 2-keto acid pathways. since these 2-keto acids are precursors of amino acids, we aimed to construct an isobutanol production platform in corynebacterium glutamicum, a well-known amino-acid-producing microorganism. analysis of this host's sensitivity to isobutanol toxicity revealed that c. glutamicum shows an increased tolerance to isobutanol relative to escherichia coli. overexpression of al ...201020376637
functional characterization of the glxr deletion mutant of corynebacterium glutamicum atcc 13032: involvement of glxr in acetate metabolism and carbon catabolite repression.recently, a cyclic amp receptor protein homologue, glxr, was reported to bind to the upstream regions of several genes involved in the regulation of diverse physiological processes in corynebacterium glutamicum. however, the function of glxr has not yet been explored in c. glutamicum in vivo using a glxr deletion mutant. therefore, this study examines the role of glxr as a repressor in glyoxylate bypass and carbon catabolite repression (ccr) using a deletion mutant. the disruption of glxr result ...201020377641
cg2091 encodes a polyphosphate/atp-dependent glucokinase of corynebacterium glutamicum.the corynebacterium glutamicum gene cg2091 is encoding a polyphosphate (polyp)/atp-dependent glucokinase (ppgk). previous work demonstrated the association of ppgk to polyp granules. the deduced amino acid sequence of ppgk shows 45% sequence identity to polyp/atp glucomannokinase of arthrobacter sp. strain km and 50% sequence identity to polyp glucokinase of mycobacterium tuberculosis h37rv. ppgk from c. glutamicum was purified from recombinant escherichia coli. polyp was highly preferred over a ...201020379711
systems-wide metabolic pathway engineering in corynebacterium glutamicum for bio-based production of diaminopentane.in the present work the gram-positive bacterium corynebacterium glutamicum was engineered into an efficient, tailor-made production strain for diaminopentane (cadaverine), a highly attractive building block for bio-based polyamides. the engineering comprised expression of lysine decarboxylase (ldcc) from escherichia coli, catalyzing the conversion of lysine into diaminopentane, and systems-wide metabolic engineering of central supporting pathways. substantially re-designing the metabolism yielde ...201020381632
decolorization and biodegradation of reactive dyes and dye wastewater by a developed bacterial consortium.a bacterial consortium (consortium gr) consisting of proteus vulgaris ncim-2027 and micrococcus glutamicus ncim-2168 could rapidly decolorize and degrade commonly-used sulfonated reactive dye green he4bd and many other reactive dyes. consortium gr shows markedly higher decolorization activity than that of the individual strains. the preferable physicochemical parameters were identified to achieve higher dye degradation and decolorization efficiency. the supplementation of cheap co-substrates (e. ...201020407917
udp-(5f)-glcnac acts as a slow-binding inhibitor of msha, a retaining glycosyltransferase.glycosyltransferase enzymes play important roles in numerous cellular pathways. despite their participation in many therapeutically relevant pathways, there is a paucity of information on how to effectively inhibit this class of enzymes. here we report that udp-(5f)-glcnac acts as a slow-binding, competitive inhibitor of the retaining glycosyltransferase msha from corynebacterium glutamicum (k(i) approximately 1.6 mum). the kinetic data are consistent with a single-step inhibition mechanism whos ...201020411981
subcellular localization and characterization of the parab system from corynebacterium glutamicum.faithful segregation of chromosomes and plasmids is a vital prerequisite to produce viable and genetically identical progeny. bacteria use a specialized segregation system composed of the partitioning proteins para and parb to segregate certain plasmids. strikingly, homologues of para and parb are found to be encoded in many chromosomes. although mutations in the chromosomal par system have effects on segregation efficiency, the exact mechanism by which the chromosomes are segregated into the da ...201020435732
utilization of phenol and naphthalene affects synthesis of various amino acids in corynebacterium glutamicum.this article reports multiple metabolic pathways of amino acid production via phenol and naphthalene use by corynebacterium glutamicum. biodegradation of phenol and naphthalene by c. glutamicum occurred in a mineral salt medium containing 1% yeast extract without any additional carbon sources. among the amino acids synthesized via the tca-cycle, glutamate synthesis increased in c. glutamicum supplemented with 8.5 mm phenol or with 4.2 mm naphthalene. aspartate synthesis significantly increased w ...201020443004
codon usage patterns in corynebacterium glutamicum: mutational bias, natural selection and amino acid conservation.the alternative synonymous codons in corynebacterium glutamicum, a well-known bacterium used in industry for the production of amino acid, have been investigated by multivariate analysis. as c. glutamicum is a gc-rich organism, g and c are expected to predominate at the third position of codons. indeed, overall codon usage analyses have indicated that c and/or g ending codons are predominant in this organism. through multivariate statistical analysis, apart from mutational selection, we identifi ...201020445740
odhi dephosphorylation kinetics during different glutamate production processes involving corynebacterium glutamicum.in corynebacterium glutamicum, the activity of the 2-oxoglutarate dehydrogenase complex was shown to be controlled by the phosphorylation of a 15-kda protein odhi by different serine/threonine protein kinases. in this paper, the phosphorylation status and kinetics of odhi dephosphorylation were assessed during glutamate producing processes triggered by either a biotin limitation or a temperature upshock from 33 degrees c to 39 degrees c. a dephosphorylation of odhi in c. glutamicum 2262 was obse ...201020449744
transcriptional regulation of gene expression in corynebacterium glutamicum: the role of global, master and local regulators in the modular and hierarchical gene regulatory network.the genus corynebacterium belongs to the taxonomic class actinobacteria representing the high g+c branch of gram-positive bacteria. among the most prominent members of this genus is corynebacterium glutamicum, which is used by the biotechnological industry for the fermentative production of l-amino acids. because of its industrial importance, c. glutamicum is one of the best-studied gram-positive bacteria and an emerging model for the suborder corynebacterineae. over the past years, the transcri ...201020491930
o-mycoloylated proteins from corynebacterium: an unprecedented post-translational modification in bacteria.o-acylation of proteins was known only in a few eukaryotic proteins but never in bacteria. we demonstrate, using a combination of protein chemistry and mass spectrometry, the occurrence of three o-acylated polypeptides in corynebacterium glutamicum, pora, porh, and an unknown small protein. the three polypeptides are o-substituted by mycolic acids, long chain alpha-alkyl and beta-hydroxy fatty acids specifically produced by members of the corynebacterineae suborder. to date these acids were desc ...201020508265
identification of a suppressor gene for the arginine-auxotrophic argj mutation in corynebacterium glutamicum.we recently proposed a metabolic engineering strategy for l-ornithine production based on the hypothesis that an increased intracellular supply of n-acetylglutamate may further enhance l-ornithine production in a well-defined recombinant strain of corynebacterium glutamicum. in this work, an argj-deficient arginine auxotrophic mutant of c. glutamicum is suppressed by a different locus of c. glutamicum atcc13032. overexpression of the ncgl1469 open reading frame (orf), exhibiting n-acetylglutamat ...201020544254
characterization of a 24-kb plasmid pcgr2 newly isolated from corynebacterium glutamicum.a 24-kb plasmid with 21 open reading frames (orfs) was newly isolated from corynebacterium glutamicum atcc 14997 and named pcgr2. three of its orfs were indispensable for stable autonomous replication of pcgr2 in c. glutamicum: in the absence of selective pressure, deletion derivatives of pcgr2 containing the three orfs showed stability in c. glutamicum for over 50 generations. the first of these orfs encoded replicase repa whose gene product revealed high amino acid sequence similarity to corre ...201020552356
identification and elimination of the competing n-acetyldiaminopentane pathway for improved production of diaminopentane by corynebacterium glutamicum.the present work describes the development of a superior strain of corynebacterium glutamicum for diaminopentane (cadaverine) production aimed at the identification and deletion of the underlying unknown n-acetyldiaminopentane pathway. this acetylated product variant, recently discovered, is a highly undesired by-product with respect to carbon yield and product purity. initial studies with c. glutamicum dap-3c, a previously derived tailor-made diaminopentane producer, showed that up to 20% of th ...201020562290
mechanism of concerted inhibition of alpha2beta2-type hetero-oligomeric aspartate kinase from corynebacterium glutamicum.aspartate kinase (ak) is the first and committed enzyme of the biosynthetic pathway producing aspartate family amino acids, lysine, threonine, and methionine. ak from corynebacterium glutamicum (cgak), a bacterium used for industrial fermentation of amino acids, including glutamate and lysine, is inhibited by lysine and threonine in a concerted manner. to elucidate the mechanism of this unique regulation in cgak, we determined the crystal structures in several forms: an inhibitory form complexed ...201020573952
an improved shuttle vector constructed for metabolic engineering research in corynebacterium glutamicum.corynebacterium glutamicum is an industrial microorganism for production of amino acids. however, the metabolic engineering in c. glutamicum has been retarded due to lack of suitable vectors. in this study, we have constructed a shuttle vector pdxw-10 which harbors a large multiple cloning site suitable for cloning multiple genes, and a tac-m promoter suitable for constitutive gene expression in c. glutamicum. the cat gene was subcloned into the vector and the expression levels of the cat protei ...201020580910
fed-batch production of a bioflocculant from corynebacterium glutamicum.the constant-rate fed-batch production of the polygalacturonic acid bioflocculant rea-11 was studied. a controlled sucrose-feeding strategy resulted in a slight improvement in biomass and a 7% reduction in flocculating activity compared with the batch process. when fed with a 3 g l(-1) urea solution, the flocculating activity was enhanced to 720 u ml(-1) in 36 h. high cell density (2.12 g l(-1)) and flocculating activity (820 u ml(-1)) were obtained in a 10-l fermentor by feeding with a sucrose- ...201020589412
biochemical characterization of two thymidylate synthases in corynebacterium glutamicum nchu 87078.the genome of corynebacterium glutamicum nchu 87078 contains two putative thymidylate synthase genes, designated cgthya and cgthyx. these two genes were expressed in escherichia coli novablue and the expressed his(6)-tagged enzymes were purified by nickel-chelate chromatography. the purified cgthya had a specific activity of 414 mu mg(-)(1) protein, whereas thymidylate synthase activity for cgthyx could not be detected in a functional complementation assay using a 10-day incubation period. gel f ...201020595007
the properties and contribution of the corynebacterium glutamicum mscs variant to fine-tuning of osmotic adaptation.based on sequence similarity, the msccg gene product of corynebacterium glutamicum belongs to the family of mscs-type mechanosensitive channels. in order to investigate the physiological significance of msccg in response to osmotic shifts in detail, we studied its properties using both patch-clamp techniques and betaine efflux kinetics. after heterologous expression in an escherichiacoli strain devoid of mechanosensitive channels, in patch-clamp analysis of giant e. coli spheroplasts msccg showe ...201020599688
regulation of the expression of genes involved in nad de novo biosynthesis in corynebacterium glutamicum.three genes, nada, nadb, and nadc, involved in nad de novo biosynthesis are broadly conserved in the genomes of numerous bacterial species. in the genome of corynebacterium glutamicum, nada and nadc but not nadb are annotated. the nada and nadc genes are located in a gene cluster containing two other genes, designated ndnr and nads herein. ndnr encodes a member of the nudix-related transcriptional regulator (nrtr) family. nads encodes a homologue of cysteine desulfurase involved in fe-s cluster ...201020601509
rama and ramb are global transcriptional regulators in corynebacterium glutamicum and control genes for enzymes of the central metabolism.in corynebacterium glutamicum, the transcriptional regulators of acetate metabolism rama (encoded by cg2831) and ramb (encoded by cg0444) play an important role in expression control of genes involved in acetate and ethanol metabolism. both regulators were speculated to have broader significance in expression control of further genes in the central metabolism of c. glutamicum. here we investigated the rama and ramb regulons by genome-wide transcriptome analysis with special emphasis on genes enc ...201020620178
phosphorylation of a novel cytoskeletal protein (rsmp) regulates rod-shaped morphology in corynebacterium glutamicum.corynebacteria grow by wall extension at the cell poles, with diviva being an essential protein orchestrating cell elongation and morphogenesis. diviva is considered a scaffolding protein able to recruit other proteins and enzymes involved in polar peptidoglycan biosynthesis. partial depletion of diviva induced overexpression of cg3264, a previously uncharacterized gene that encodes a novel coiled coil-rich protein specific for corynebacteria and a few other actinomycetes. by partial depletion a ...201020622015
citrate synthase in corynebacterium glutamicum is encoded by two glta transcripts which are controlled by rama, ramb, and glxr.citrate synthase (cs) is located at a major branch point in the metabolism and is required for both tricarboxylic acid and glyoxylic acid cycle activity. here we show that the cs gene glta of corynebacterium glutamicum is monocistronic, but that two transcripts are formed with their transcript initiation sites located 121bp and 357bp upstream of the translational start codon, respectively. northern blot analyses revealed that during growth on acetate the short transcript prevails, whereas during ...201020630483
recovery of zero-valent gold from cyanide solution by a combined method of biosorption and incineration.a new combined way of biosorption and incineration is presented for the recovery of gold from gold-cyanide solutions. decarboxylated biosorbent (dcb) was prepared by removing interfering carboxyl groups from the surface of inactive corynebacterium glutamicum. the recovery of gold from the exhausted biosorbents was performed using elution or incineration. the maximum gold(i) uptakes were obtained as 50.19 and 86.16mg/g for the raw biomass and dcb, respectively. the biosorption performance of dcb ...201020630746
alternative thymidylate synthase, thyx, involved in corynebacterium glutamicum atcc 13032 survival during stationary growth phase.a blastp search has shown the presence of a gene homologous to an alternative thymidylate synthase (ts), thyx, in corynebacterium glutamicum atcc 13032. to determine if thyx is functionally analogous to thya, thyx was cloned in a plasmid and the resulting construct was transferred by transformation into a thya mutant of escherichia coli. the thyx from c. glutamicum compensated for the defect in ts-deficient e. coli. a functional knockout of the thyx gene was constructed by allelic replacement us ...201020636973
treatment of phenol-contaminated soil by corynebacterium glutamicum and toxicity removal evaluation.biodegradation of phenol-contaminated soils using corynebacterium glutamicum, was optimized in this study. phenol degradation by c. glutamicum was observed in soil supplemented with 1% yeast extract as a substrate. we determined the optimal inoculation size of c. glutamicum (7.4 log(10) cfu ml(-1)) for the degradation of phenol-contaminated soil. under optimal conditions (1% yeast extract and 7.4 log(10) cfu ml(-1) of c. glutamicum), the efficiency of phenol degradation in soil was greater than ...201020638173
production of the amino acids l-glutamate, l-lysine, l-ornithine and l-arginine from arabinose by recombinant corynebacterium glutamicum.amino acid production processes with corynebacterium glutamicum are based on media containing glucose from starch hydrolysis or fructose and sucrose as present in molasses. simultaneous utilization of various carbon sources, including glucose, fructose and sucrose, in blends is a typical characteristic of this bacterium. the renewable non-food carbon source arabinose, which is present in hemicellulosic hydrolysates, cannot be utilized by most c. glutamicum strains. heterologous expression of the ...201020638422
the pstscab operon for phosphate uptake is regulated by the global regulator glxr in corynebacterium glutamicum.the pstscab operon of corynebacterium glutamicum, which encodes a high affinity transport system for uptake of the phosphorus source inorganic phosphate, is induced upon phosphate starvation involving activation by the two-component regulatory system phos-phor. partial phosphate starvation induction of the pstscab operon in a deltaphors mutant indicated the involvement of (an) additional transcriptional regulator(s). here, glxr, a global camp-dependent transcriptional regulator, was shown to bin ...201020638427
stationary versus non-stationary (13)c-mfa: a comparison using a consistent dataset.besides the well-established (13)c-metabolic flux analysis ((13)c-mfa) which characterizes a cell's fluxome in a metabolic and isotopic stationary state a current area of research is isotopically non-stationary mfa. non-stationary (13)c-mfa uses short-time isotopic transient data instead of long-time isotopic equilibrium data and thus is capable to resolve fluxes within much shorter labeling experiments. however, a comparison of both methods with data from one single experiment has not been made ...201020638432
rosr (cg1324), a hydrogen peroxide-sensitive marr-type transcriptional regulator of corynebacterium glutamicum.the cg1324 gene (rosr) of corynebacterium glutamicum encodes a marr-type transcriptional regulator. by a comparative transcriptome analysis with dna microarrays of a δrosr mutant and the wild type and subsequent emsas with purified rosr protein, direct target genes of rosr were identified. the narkghji operon, which encodes a nitrate/nitrite transporter and the dissimilatory nitrate reductase complex, was activated by rosr. all other target genes were repressed by rosr. they encode four putative ...201020643656
biochemical characterisation of aconitase from corynebacterium glutamicum.in this work, aconitase of the biotechnologically relevant microorganism corynebacterium glutamicum was characterised. the specific activity of aconitase in extracts of glucose-grown cells was determined by four different assays. in three of them the formation or disappearance of cis-aconitate was measured, whereas in the fourth assay the aconitase reaction was coupled with isocitrate dehydrogenase. the highest activity was determined with cis-aconitate as substrate (0.433+/-0.054umg(-1)) and th ...201020647021
quantitative proteomic overview on the corynebacterium glutamicuml-lysine producing strain dm1730.corynebacterium glutamicum is one of the most important microorganisms because of its ability to produce and secrete glutamate, lysine and other amino acids. to optimize biotechnological amino acid synthesis it is therefore necessary to understand well how metabolic fluxes can be altered by studying the proteins directing these fluxes. in this work we give a comprehensive quantitative outline about the proteomic state of the l-lysine producing mutant strain dm1730 compared to wild type strain at ...201020650338
tetrahydrolipstatin inhibition, functional analyses, and three-dimensional structure of a lipase essential for mycobacterial viability.the highly complex and unique mycobacterial cell wall is critical to the survival of mycobacteria in host cells. however, the biosynthetic pathways responsible for its synthesis are, in general, incompletely characterized. rv3802c from mycobacterium tuberculosis is a partially characterized phospholipase/thioesterase encoded within a genetic cluster dedicated to the synthesis of core structures of the mycobacterial cell wall, including mycolic acids and arabinogalactan. enzymatic assays performe ...201020656688
l-glutamine as a nitrogen source for corynebacterium glutamicum: derepression of the amtr regulon and implications for nitrogen sensing.corynebacterium glutamicum, a gram-positive soil bacterium employed in the industrial production of various amino acids, is able to use a number of different nitrogen sources, such as ammonium, urea or creatinine. this study shows that l-glutamine serves as an excellent nitrogen source for c. glutamicum and allows similar growth rates in glucose minimal medium to those in ammonium. a transcriptome comparison revealed that the nitrogen starvation response was elicited when glutamine served as the ...201020656783
corynebacterium glutamicum exhibits a membrane-related response to a small ferrocene-conjugated antimicrobial peptide.multiresistant bacteria are becoming more and more widespread. it is therefore necessary to have new compound groups in hand, such as small cationic peptides, to cope with these challenges. in this work, we present a comprehensive approach by monitoring protein expression profiles in a gram-positive bacterium (corynebacterium glutamicum) to investigate the cellular response to such a compound, a ferrocene-conjugated arginine- and tryptophan-rich pentapeptide. to achieve this, a proteomic outline ...201020658302
putrescine production by engineered corynebacterium glutamicum.here, we report the engineering of the industrially relevant corynebacterium glutamicum for putrescine production. c. glutamicum grew well in the presence of up to 500 mm of putrescine. a reduction of the growth rate by 34% and of biomass formation by 39% was observed at 750 mm of putrescine. c. glutamicum was enabled to produce putrescine by heterologous expression of genes encoding enzymes of the arginine- and ornithine decarboxylase pathways from escherichia coli. the results showed that the ...201020661733
the e2 domain of odha of corynebacterium glutamicum has succinyltransferase activity dependent on lipoyl residues of the acetyltransferase acef.oxoglutarate dehydrogenase (odh) and pyruvate dehydrogenase (pdh) complexes catalyze key reactions in central metabolism, and in corynebacterium glutamicum there is indication of an unusual supercomplex consisting of acee (e1), acef (e2), and lpd (e3) together with odha. odha is a fusion protein of additional e1 and e2 domains, and odha orthologs are present in all corynebacterineae, including, for instance, mycobacterium tuberculosis. here we show that deletion of any of the individual domains ...201020675489
metabolic engineering of escherichia coli and corynebacterium glutamicum for the production of l-threonine.l-threonine is an essential amino acid for mammals and as such has a wide and expanding application in industry with a fast growing market demand. the major method of production of l-threonine is microbial fermentation. to optimize l-threonine production the fundamental solution is to develop robust microbial strains with high productivity and stability. metabolic engineering provides an effective alternative to the random mutation for strain development. in this review, the updated information ...201120688145
Displaying items 1201 - 1300 of 2194