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identification of succinate exporter in corynebacterium glutamicum and its physiological roles under anaerobic conditions.corynebacterium glutamicum produces succinate from glucose via the reductive tricarboxylic acid cycle under microaerobic and anaerobic conditions. we identified a ncgl2130 gene of c. glutamicum as a novel succinate exporter that functions in succinate production, and designated suce1. suce1 expression levels were higher under microaerobic conditions than aerobic conditions, and overexpression or disruption of suce1 respectively increased or decreased succinate productivity during fermentation. u ...201121420450
metabolic engineering of 1,2-propanediol pathways in corynebacterium glutamicum.we analyzed 1,2-propanediol (1,2-pd) production in metabolically engineered corynebacterium glutamicum. wild-type c. glutamicum produced 93 µm 1,2-pd after 132 h incubation under aerobic conditions. no gene encoding the methylglyoxal synthase (mgs) which catalyzes the first step of 1,2-pd synthesis from the glycolytic pathway was detected on the c. glutamicum genome, but several genes annotated as encoding putative aldo-keto reductases (akrs) were present. akr functions as a methylglyoxal reduct ...201121424269
lipoarabinomannan biosynthesis in corynebacterineae: the interplay of two +¦(1ôåæ2)-mannopyranosyltransferases mptc and mptd in mannan branching.lipomannan (lm) and lipoarabinomannan (lam) are key corynebacterineae glycoconjugates that are integral components of the mycobacterial cell wall, and are potent immunomodulators during infection. lam is a complex heteropolysaccharide synthesized by an array of essential glycosyltransferase family c (gt-c) members, which represent potential drug targets. herein, we have identified and characterized two open reading frames from corynebacterium glutamicum that encode for putative gt-cs. deletion o ...201121435038
corynebacterium glutamicum tailored for efficient isobutanol production.we recently engineered corynebacterium glutamicum for aerobic production of 2-ketoisovalerate by inactivation of the pyruvate dehydrogenase complex, pyruvate:quinone oxidoreductase, transaminase b, and additional overexpression of the ilvbncd genes, encoding acetohydroxyacid synthase, acetohydroxyacid isomeroreductase, and dihydroxyacid dehydratase. based on this strain, we engineered c. glutamicum for the production of isobutanol from glucose under oxygen deprivation conditions by inactivation ...201121441331
identification and application of a different glucose uptake system that functions as an alternative to the phosphotransferase system in corynebacterium glutamicum.corynebacterium glutamicum uses the phosphoenolpyruvate-dependent sugar phosphotransferase system (pts) to uptake and phosphorylate glucose; no other route has yet been identified. disruption of the ptsh gene in wild-type c. glutamicum resulted, as expected, in a phenotype exhibiting little growth on any of the pts sugars: glucose, fructose, and sucrose. however, a suppressor mutant that grew on glucose but not on the other two sugars was spontaneously isolated from the pts-negative strain wt?pt ...201121452034
the ncgl1108 (phep (cg)) gene encodes a new l: -phe transporter in corynebacterium glutamicum.corynebacterium glutamicum played a central role in the establishment of fermentative production of amino acids, and it is a model for genetic and physiological studies. the general aromatic amino acid transporter, arop( cg ), was the sole functionally identified aromatic amino acid transporter from c. glutamicum. in this study, the ncgl1108 (named as phep ( cg )), which is located upstream of the genetic cluster (ncgl1110 ∼ ncgl1113) for resorcinol catabolism, was identified as a new l: -phe sp ...201121468701
phosphotransferase system-independent glucose utilization in corynebacterium glutamicum by inositol permeases and glucokinases.phosphoenolpyruvate-dependent glucose phosphorylation via the phosphotransferase system (pts) is the major path of glucose uptake in corynebacterium glutamicum, but some growth from glucose is retained in the absence of the pts. the growth defect of a deletion mutant lacking the general pts component hpr in glucose medium could be overcome by suppressor mutations leading to the high expression of inositol utilization genes or by the addition of inositol to the growth medium if a glucokinase is o ...201121478323
investigation of phosphorylation status of odhi protein during penicillin- and tween 40-triggered glutamate overproduction by corynebacterium glutamicum.glutamate overproduction by corynebacterium glutamicum is triggered by treatment with penicillin or tween 40 and is accompanied by a decrease in 2-oxoglutarate dehydrogenase complex (odhc) activity. we have reported that de novo synthesis of odhi, which inhibits odhc activity by interacting specifically with the e1o subunit of odhc (odha), is induced by penicillin, and that odhi overexpression induces glutamate overproduction in the absence of any triggers for glutamate overproduction. in this s ...201121503757
tools for genetic manipulations in corynebacterium glutamicum and their applications.corynebacterium glutamicum is an important industrial producer of various amino acids with great potential for the production of other metabolites. the complete genome sequences of two c. glutamicum strains were determined and the use of genome-based approaches (transcriptomics, proteomics, metabolomics, and fluxomics) provided large amounts of data on the metabolism of this bacterium and its regulation. many tools for genetic manipulations in c. glutamicum have been developed and used for the a ...201121519933
lipoarabinomannan and related glycoconjugates: structure, biogenesis and role in mycobacterium tuberculosis physiology and host-pathogen interaction.approximately one third of the world's population is infected with mycobacterium tuberculosis, the causative agent of tuberculosis. this bacterium has an unusual lipid-rich cell wall containing a vast repertoire of antigens, providing a hydrophobic impermeable barrier against chemical drugs, thus representing an attractive target for vaccine and drug development. apart from the mycolyl-arabinogalactan-peptidoglycan complex, mycobacteria possess several immunomodulatory constituents, notably lipo ...201121521247
high yield secretion of heterologous proteins in corynebacterium glutamicum using its own tat-type signal sequence.efficient protein secretion, the basis of large-scale production of many compounds central to the biotechnology industry, is achieved by signal peptide and propeptide optimization in addition to optimizing host factors affecting heterologous protein production. here, we fused green fluorescent protein (gfp) to the recently identified tat-type secretory signal peptide of cgr0949 to demonstrate a high-yield protein secretion system of corynebacterium glutamicum. the resultant secretion vector faci ...201121523478
co-evolutionary analysis enables rational deregulation of allosteric enzyme inhibition in corynebacterium glutamicum for lysine production.product feedback inhibition of allosteric enzymes is an essential issue for developing highly efficient microbial strains for bioproduction. here we use aspartokinase from corynebacterium glutamicum (cgak), a key enzyme controlling the biosynthesis of industrially important aspartate family amino acids, as a model to demonstrate a fast and efficient approach to deregulate allostery. in the last fifty years many researchers and companies have made considerable efforts to deregulate this enzyme fr ...201121531824
engineering bacillus subtilis for isobutanol production by heterologous ehrlich pathway construction and the biosynthetic 2-ketoisovalerate precursor pathway overexpression.in the present work, bacillus subtilis was engineered as the cell factory for isobutanol production due to its high tolerance to isobutanol. initially, an efficient heterologous ehrlich pathway controlled by the promoter p(43) was introduced into b. subtilis for the isobutanol biosynthesis. further, investigation of acetolactate synthase of b. subtilis, ketol-acid reductoisomerase, and dihydroxy-acid dehydratase of corynebacterium glutamicum responsible for 2-ketoisovalerate precursor biosynthes ...201121533914
biotechnological production of polyamines by bacteria: recent achievements and future perspectives.in bacteria, the pathways of polyamine biosynthesis start with the amino acids l: -lysine, l: -ornithine, l: -arginine, or l: -aspartic acid. some of these polyamines are of special interest due to their use in the production of engineering plastics (e.g., polyamides) or as curing agents in polymer applications. at present, the polyamines for industrial use are mainly synthesized on chemical routes. however, since a commercial market for polyamines as well as an industry for the fermentative pro ...201121552989
crystal structures of the transcriptional repressor rolr reveals a novel recognition mechanism between inducer and regulator.many members of the tetr family control the transcription of genes involved in multidrug resistance and pathogenicity. rolr (resorcinolregulator), the recently reported tetr-type regulator for aromatic catabolism from corynebacterium glutamicum, distinguishes itself by low sequence similarities and different regulation from the previously known members of the tetr family. here we report the crystal structures of rolr in its effector-bound (with resorcinol) and aop- forms at 2.5 å and 3.6 å, resp ...201121559286
purification and characterization of an arginine regulatory protein, argr, in corynebacterium glutamicum.corynebacterium glutamicum, a gram-positive bacterium, has been widely used for industrial amino acid production. we previously showed that, in c. glutamicum, argcjbdfrgh arginine biosynthesis genes are clustered but independently transcribed from argc and argg promoters, leading to the generation of two transcripts corresponding to argcjbdfr and arggh. in this report, we show the effect of the c. glutamicum argr repressor on argc and argg promoters by overexpressing or disrupting the argr gene. ...201121559975
kinetic characterisation of recombinant corynebacterium glutamicum nad(+)-dependent ldh over-expressed in e. coli and its rescue of an lldd (-) phenotype in c. glutamicum: the issue of reversibility re-examined.the ldh gene of corynebacterium glutamicum atcc 13032 (gene symbol cg3219, encoding a 314 residue nad(+)-dependent l: -(+)-lactate dehydrogenase, ec 1.1.1.27) was cloned into the expression vector pkk388-1 and over-expressed in an ldha-null e. coli tg1 strain upon isopropyl-β-d-thiogalactopyranoside (iptg) induction. the recombinant protein (referred to here as cgldh) was purified by a combination of dye-ligand and ion-exchange chromatography. though active in its absence, cgldh activity is enha ...201121567176
corynebacterium deserti sp. nov., isolated from desert in the west of china.a novel coryneform bacterium, was isolated from a sand sample collected in desert in the west of china. the strain comprised gram-positive, non-spore-forming, catalase-positive and irregular rods. comparative 16s rrna gene sequencing analysis demonstrated that the strain, gimn1.010(t), belonged to the genus corynebacterium and was closely related to c. glutamicum atcc 13032(t) (98.4%). however, dna relatedness between gimn1.010(t) and corynebacterium glutamicum was observed to be only 22.4±1.72% ...201121571935
osmotic stress response in c. glutamicum: impact of channel- and transporter-mediated potassium accumulation.potassium accumulation is an essential aspect of bacterial response to diverse stress situations; consequently its uptake plays a pivotal role. here, we show that the gram-positive soil bacterium corynebacterium glutamicum which is employed for the large-scale industrial production of amino acids requires potassium under conditions of ionic and non-ionic osmotic stress. besides the accumulation of high concentrations of potassium contributing significantly to the osmotic potential of the cytopla ...201121614527
identification of spia that interacts with corynebacterium glutamicum whca using two-hybrid system.the corynebacterium glutamicum whca gene is known to play a negative role in the expression of genes responding to oxidative stress. the encoded protein contains conserved cysteines, which likely coordinate the redox-sensitive fe-s cluster. to identify proteins which may interact with whca, we employed a two-hybrid system utilizing whca as a 'bait'. upon screening, several partner proteins were isolated from the c. glutamicum genomic library. sequencing analysis of the isolated clones revealed o ...201121623894
monitoring enzyme expression of a branched respiratory chain of corynebacterium glutamicum using an egfp reporter gene.to investigate the expressional control of branched respiratory chain complexes of the amino-acid producing bacterium corynebacterium glutamicum according to growth conditions, the expression indexes of the ndh, sdh, qcrcab, ctacf, ctad, ctae, and cydab genes were estimated under aerobic and microaerobic, and carbon-rich and -poor conditions. the promoter region of each target gene was cloned upstream of the egfp gene on expression vector pvk6, and the nine reporter constructs were transformed i ...201121643696
characterization of the mannitol catabolic operon of corynebacterium glutamicum.corynebacterium glutamicum encodes a mannitol catabolic operon, which comprises three genes: the deor-type repressor coding gene mtlr (sucr), an mfs transporter gene (mtlt), and a mannitol 2-dehydrogenase gene (mtld). the mtlr gene is located upstream of the mtltd genes in the opposite orientation. in spite of this, wild-type c. glutamicum lacks the ability to utilize mannitol. this wild-type phenotype results from the genetic regulation of the genes coding for mannitol transport and catalytic p ...201121655984
a guide through the computational analysis of isotope-labeled mass spectrometry-based quantitative proteomics data: an application study.abstract: background: mass spectrometry-based proteomics has reached a stage where it is possible to comprehensively analyze the whole proteome of a cell in one experiment. here, the employment of stable isotopes has become a standard technique to yield relative abundance values of proteins. in recent times, more and more experiments are conducted that depict not only a static image of the up- or down-regulated proteins at a distinct time point but instead compare developmental stages of an orga ...201121663690
regulatory and metabolic networks for amino acid production by corynebacterium glutamicum. 201121664532
genome-wide identification of in vivo binding sites of glxr, a cyclic amp receptor protein-type regulator in corynebacterium glutamicum.corynebacterium glutamicum glxr is a cyclic amp (camp) receptor protein-type regulator. although over 200 glxr-binding sites in the c. glutamicum genome are predicted in silico, studies on the physiological function of glxr have been hindered by the severe growth defects of a glxr mutant. this study identified the glxr regulon by chromatin immunoprecipitation in conjunction with microarray (chip-chip) analyses. in total, 209 regions were detected as in vivo glxr-binding sites. in vitro binding a ...201121665967
proteomics of corynebacteria: from biotechnology workhorses to pathogens.corynebacteria belong to the high g+c gram-positive bacteria (actinobacteria) and are closely related to mycobacterium and nocardia species. the best investigated member of this group of almost seventy species is corynebacterium glutamicum, a soil bacterium isolated in 1957, which is used for the industrial production of more than two million tons of amino acids per year. this review focuses on the technical advances made in proteomics approaches during the last years and summarizes applications ...201121674800
high-throughput transposon mutagenesis of corynebacterium glutamicum.construction of gene disruption mutants and analysis of the resultant phenotypes are an important strategy to study gene function. a simple and high-throughput method developed for microorganisms combines two different types of transposons, direct genomic dna amplification and thermal asymmetric interlaced-pcr. the considerable utility of this approach is demonstrable in corynebacterium glutamicum, where 18,000 transposon disruptants enabled the generation of an insertion library covering nearly ...201121815106
the two-component signal transduction system coprs of corynebacterium glutamicum is required for adaptation to copper-excess stress.copper is an essential cofactor for many enzymes but at high concentrations it is toxic for the cell. copper ion concentrations =50 µm inhibited growth of corynebacterium glutamicum. the transcriptional response to 20 µm cu(2+) was studied using dna microarrays and revealed 20 genes that showed a = 3-fold increased mrna level, including cg3281-cg3289. several genes in this genomic region code for proteins presumably involved in the adaption to copper-induced stress, e. g. a multicopper oxidase ( ...201121799779
functional expression of the porah channel from corynebacterium glutamicum in cell-free expression systems: implications on the role of the naturally occurring mycolic acid modification.pora and porh are two small membrane proteins from the outer membrane of corynebacterium glutamicum which have been shown to form heteromeric ion channels and to be post- translationally modified by mycolic acids. any structural details of the channel could not be analyzed so far due to tremendous difficulties in the production of sufficient amounts of protein samples. cell-free (cf) expression is a new and remarkably successful strategy for the production of membrane proteins for which toxicity ...201121799011
amino acid production from rice straw and wheat bran hydrolysates by recombinant pentose-utilizing corynebacterium glutamicum.corynebacterium glutamicum wild type lacks the ability to utilize the pentose fractions of lignocellulosic hydrolysates, but it is known that recombinants expressing the arabad operon and/or the xyla gene from escherichia coli are able to grow with the pentoses xylose and arabinose as sole carbon sources. recombinant pentose-utilizing strains derived from c. glutamicum wild type or from the l: -lysine-producing c. glutamicum strain dm1729 utilized arabinose and/or xylose when these were added as ...201121796382
comparative 13c-metabolic flux analysis of pdhc-deficient l-valine producing corynebacterium glutamicum.l-valine can be formed successfully using c. glutamicum strains missing an active pyruvate dehydrogenase enzyme complex (pdhc). c. glutamicum wild type and four pdhc-deficient strains were compared by (13)c-metabolic flux analysis especially focusing on the split ratio between glycolysis and pentose phosphate pathway (ppp). compared to the wild type showing a carbon flux of 69 ± 14% through the ppp, a strong increase in the ppp flux was observed in pdhc-deficient strains with a maximum of 113 ± ...201121784914
bio-based production of the platform chemical 1,5-diaminopentane.in the rising era of bio-economy, the five carbon compound 1,5-diaminopentane receives increasing interest as platform chemical, especially as innovative building block for bio-based polymers. the vital interest in bio-based supply of 1,5-diaminopentane has strongly stimulated research on the development of engineered producer strains. based on the state-of-art knowledge on the pathways and reactions linked to microbial 1,5-diaminopentane metabolism, the review covers novel systems metabolic eng ...201121761208
advanced mudpit as a next step towards high proteome coverage.we present a simple, time and cost efficient approach to tackle the proteome of prokaryotic organisms. to obtain large datasets of complex biological experiments high throughput and time and cost efficient methods still have to be developed and refined. in this study, we combined well approved techniques, namely elevated chromatographic temperatures, long reversed phase columns and the multidimensional protein identification technology mudpit to achieve high proteome coverage. the advanced mudpi ...201121751368
synthesis of +¦-aminobutyric acid by expressing lactobacillus brevis-derived glutamate decarboxylase in the corynebacterium glutamicum strain atcc 13032.purpose of work: purpose of this work is to synthesize +¦-aminobutyric acid by glutamate-producing species expressing lactobacillus brevis-derived glutamate decarboxylase genes, i.e. recombinant corynebacterium glutamicum strains, which directly convert endogenous l: -glutamate precursor into +¦-aminobutyric acid (gaba) through single-step fermentation. to express exogenous glutamate decarboxylase (gad) in an l: -glutamate-producing strain, lactobacillus brevis lb85, which can produce gaba, was ...201121826397
metabolic engineering of cellular transport for overproduction of the platform chemical 1,5-diaminopentane in corynebacterium glutamicum.the present work describes the development of a superior strain of corynebacterium glutamicum for diaminopentane (cadaverine) production via metabolic engineering of cellular transport processes. in c. glutamicum dap-3c, a tailor-made producer, the diaminopentane forming enzyme, lysine decarboxylase, was inhibited in vivo by its end-product, suggesting a potential bottleneck at the level of the export. the previously proposed lysine exporter lyse was shown not to be involved in diaminopentane ex ...201121821142
expression, purification, crystallization and preliminary crystallographic analysis of cg1458: a novel oxaloacetate decarboxylase from corynebacterium glutamicum.oxaloacetate decarboxylase catalyses the decarboxylation of oxaloacetate to pyruvate and co(2). recently, the corynebacterium glutamicum gene product cg1458 was determined to be a soluble oxaloacetate decarboxylase. to elucidate the mechanism of oxaloacetate decarboxylation by cg1458, recombinant cg1458 was purified and crystallized. the best crystal was grown from 0.2ôçàm mgcl(2), 0.1ôçàm bis-tris ph 6.0, 25%(w/v) polyethylene glycol 3350 using the hanging-drop method. the crystals belonged to ...201121821907
comparison between elementary flux modes analysis and 13c-metabolic fluxes measured in bacterial and plant cells.abstract:201121682932
lrp of corynebacterium glutamicum controls expression of the brnfe operon encoding the export system for l-methionine and branched-chain amino acids.corynebacterium glutamicum possesses export systems for various amino acids including brnfe, a two-component export system for l-methionine and the branched-chain amino acids l-valine, l-isoleucine and l-leucine. a gene for a putative transcriptional regulator of the lrp family is transcribed divergently to the brnfe operon and is required for l-isoleucine export. by comparing global gene expression changes due to l-isoleucine addition we revealed increased brnfe expression in response to l-isol ...201121683740
corynebacterium glutamicum rnase e/g-type endoribonuclease encoded by ncgl2281 is involved in the 5' maturation of 5s rrna.corynebacterium glutamicum has one rnase e/g ortholog and one rnase j ortholog but no rnase y. we previously reported that the c. glutamicum ncgl2281 gene encoding the rnase e/g ortholog complemented the rng::cat mutation in escherichia coli but not the rne-1 mutation. in this study, we constructed an ncgl2281 knockout mutant and found that the mutant cells accumulated 5s rrna precursor molecules. the processing of 16s and 23s rrna, trna, and tmrna was normal. primer extension analysis revealed ...201121717142
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
identification of the membrane protein suce and its role in succinate transport in corynebacterium glutamicum.succinic acid is excreted during anaerobiosis by many bacteria, and manifold applications are known making the biotechnological production of succinate attractive. although the pathways for succinate formation are known, succinate export is not understood in most of the succinate producing bacteria. here, we present a bioinformatic approach for identification of a putative succinate export system in corynebacterium glutamicum. the subsequent screening revealed that a mutant in the gene cg2425 is ...201120809072
enhanced production of l-arginine by expression of vitreoscilla hemoglobin using a novel expression system in corynebacterium crenatum.corynebacterium crenatum sypa 5-5 is an aerobic and industrial l: -arginine producer. it was proved that the corynebacterium glutamicum/escherichia coli shuttle vector pjc1 could be extended in c. crenatum efficiently when using the chloramphenicol acetyltransferase gene (cat) as a reporter under the control of promoter tac. the expression system was applied to over-express the gene vgb coding vitreoscilla hemoglobin (vhb) to further increase the dissolved oxygen in c. crenatum. as a result, the ...201120835781
autoinduction of a genetic locus encoding putative acyltransferase in corynebacterium glutamicum.a genetic locus, encoding putative acyltransferase, was induced by autoinducers in corynebacterium glutamicum. the autoinducers were maximally produced by the bacterium after 24 h culture. those molecules are resistant to proteinase k treatment (300 μg ml(-1)) for 30 min at 37°c or at 121°c for 15 min, and remained stable after extensive storage at 4°c. autoinducers in the cell-free culture fluids from corynebacterium ammoniagenes and pseudomonas aeruginosa also induced the expression of acyltra ...201120821248
production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in recombinant corynebacterium glutamicum using propionate as a precursor.lipopolysaccharides free p[3-hydroxybutyrate (3hb)-co-3-hydroxyvalerate (3hv)] production was achieved using recombinant corynebacterium glutamicum harboring polyhydroxyalkanoate (pha) biosynthetic genes from ralstonia eutropha. cells grown on glucose with feeding of propionate as a precursor of 3hv unit accumulated 8-47wt% of p(3hb-co-3hv). the 3hv fraction in the copolymer was varied from 0 to 28mol% depending on the propionate concentrations.201120692303
Construction of a novel sacB-based system for marker-free gene deletion in Corynebacterium glutamicum.Bacillus subtilis sacB gene with its 463bp upstream region including its native promoter has been used for marker-free gene deletion in Corynebacterium glutamicum, but the role of this upstream region is not clear. In this study, it was demonstrated that the upstream region of sacB failed to efficiently promote its expression in C. glutamicum, and the native promoter of sacB is weak in C. glutamicum. The expression level of sacB under its native promoter in C. glutamicum is not high enough for c ...201222100974
Efficient aerobic succinate production from glucose in minimal medium with Corynebacterium glutamicum.Corynebacterium glutamicum, an established industrial amino acid producer, has been genetically modified for efficient succinate production from the renewable carbon source glucose under fully aerobic conditions in minimal medium. The initial deletion of the succinate dehydrogenase genes (sdhCAB) led to an accumulation of 4.7 g l(-1) (40 mM) succinate as well as high amounts of acetate (125 mM) as by-product. By deleting genes for all known acetate-producing pathways (pta-ackA, pqo and cat) ace ...201222018023
Physiology and global gene expression of a Corynebacterium glutamicum ?F(1)F(O)-ATP synthase mutant devoid of oxidative phosphorylation.A mutant of Corynebacterium glutamicum ATCC 13032 with a deletion of the atpBEFHAGDC genes encoding F(1)F(O)-ATP synthase was characterized. Whereas no growth was observed with acetate as sole carbon source, the ?F(1)F(O) mutant reached 47% of the growth rate and 65% of the biomass of the wild type during shake-flask cultivation in glucose minimal medium. Initially, the mutant strain showed a strongly increased glucose uptake rate accompanied by a high oxygen consumption rate and pyruvate secret ...201222050934
phenol degradation activity and reusability of corynebacterium glutamicum coated with nh(2)-functionalized silica-encapsulated fe(3)o(4) nanoparticles.in this study, a novel method to immobilize and separate corynebacterium glutamicum for phenol degradation was developed using fe(3)o(4) nanoparticles (nps). the fe(3)o(4) nps were encapsulated with silica and functionalized with nh(2) groups to enhance their capacity to adsorb on the cell surface. the results showed that the nh(2)-functionalized silica-encapsulated fe(3)o(4) nps strongly adsorbed on the cell surface of c. glutamicum during 32d culture without any interruptions of their normal c ...201222093979
efflux permease cgacr3-1 of corynebacterium glutamicum is an arsenite-specific antiporter.resistance to arsenite (as(iii)) by cells is generally accomplished by arsenite efflux permeases from acr3 or arsb unrelated families. we analyzed the function of three acr3 proteins from corynebacterium glutamicum, cgacr3-1, cgacr3-2, and cgacr3-3. cgacr3-1 conferred the highest level of as(iii) resistance and accumulation in vivo. cgacr3-1 was also the most active when everted membranes vesicles from escherichia coli or c. glutamicum mutants were assayed for efflux with different energy source ...201222102279
regulation of the malic enzyme gene male by the transcriptional regulator malr in corynebacterium glutamicum.corynebacterium glutamicum is a gram-positive nonpathogenic bacterium that is used for the biotechnological production of amino acids. here, we investigated the transcriptional control of the male gene encoding malic enzyme (male) in c. glutamicum atcc13032, which is known to involve the nitrogen regulator amtr. gel shift experiments using purified regulators rama and ramb revealed binding of these regulators to the male promoter. in dna-affinity purification experiments a hitherto uncharacteriz ...201222261175
genome sequence of corynebacterium glutamicum atcc 14067, which provides insight into amino acid biosynthesis in coryneform bacteria.we report the genome sequence of corynebacterium glutamicum atcc 14067 (once named brevibacterium flavum), which is useful for taxonomy research and further molecular breeding in amino acid production. preliminary comparison with those of the reported coryneform strains revealed some notable differences that might be related to the difficulties in molecular manipulation.201222247536
engineering corynebacterium glutamicum for the production of pyruvate.a corynebacterium glutamicum strain with inactivated pyruvate dehydrogenase complex and a deletion of the gene encoding the pyruvate:quinone oxidoreductase produces about 19 mm l: -valine, 28 mm l: -alanine and about 55 mm pyruvate from 150 mm glucose. based on this double mutant c. glutamicum △acee △pqo, we engineered c. glutamicum for efficient production of pyruvate from glucose by additional deletion of the ldha gene encoding nad(+)-dependent l: -lactate dehydrogenase (ldha) and introduction ...201222228312
transcriptional cross-regulation between gram-negative and gram-positive bacteria, demonstrated using argp-argo of escherichia coli and lysg-lyse of corynebacterium glutamicum.the protein-gene pairs argp-argo of escherichia coli and lysg-lyse of corynebacterium glutamicum are orthologous, with the first member of each pair being a lysr-type transcriptional regulator and the second its target gene encoding a basic amino acid exporter. whereas lyse is an exporter of arginine (arg) and lysine (lys) whose expression is induced by arg, lys, or histidine (his), argo exports arg alone, and its expression is activated by arg but not lys or his. we have now reconstituted in e. ...201222904281
destabilized eyfp variants for dynamic gene expression studies in corynebacterium glutamicum.fluorescent reporter proteins are widely used for the non-invasive monitoring of gene expression patterns, but dynamic measurements are hampered by the extremely high stability of gfp and homologue proteins. in this study, we used ssra-mediated peptide tagging for the construction of unstable variants of the gfp derivative eyfp (enhanced yellow fluorescent protein) and applied those for transient gene expression analysis in the industrial platform organism corynebacterium glutamicum.201222938655
the tetr-type transcriptional repressor rolr from corynebacterium glutamicum regulates resorcinol catabolism by binding to a unique operator, rolo.the rol (designated for resorcinol) gene cluster rolrhmd is involved in resorcinol catabolism in corynebacterium glutamicum, and rolr is the tetr-type regulator. in this study, we investigated how rolr regulated the transcription of the rol genes in c. glutamicum. the transcription start sites and promoters of rolr and rolhmd were identified. quantitative reverse transcription-pcr and promoter activity analysis indicated that rolr negatively regulated the transcription of rolhmd and of its own g ...201222706057
biochemical and molecular characterization of the gentisate transporter genk in corynebacterium glutamicum.gentisate (2,5-dihydroxybenzoate) is a key ring-cleavage substrate involved in various aromatic compounds degradation. corynebacterium glutamicum atcc13032 is capable of growing on gentisate and genk was proposed to encode a transporter involved in this utilization by its disruption in the restriction-deficient mutant res167. its biochemical characterization by uptake assay using [(14)c]-labeled gentisate has not been previously reported.201222808015
two-component signal transduction in corynebacterium glutamicum and other corynebacteria: on the way towards stimuli and targets.in bacteria, adaptation to changing environmental conditions is often mediated by two-component signal transduction systems. in the prototypical case, a specific stimulus is sensed by a membrane-bound histidine kinase and triggers autophosphorylation of a histidine residue. subsequently, the phosphoryl group is transferred to an aspartate residue of the cognate response regulator, which then becomes active and mediates a specific response, usually by activating and/or repressing a set of target ...201222539022
characterization of oxyr as a negative transcriptional regulator that represses catalase production in corynebacterium diphtheriae.corynebacterium diphtheriae and corynebacterium glutamicum each have one gene (cat) encoding catalase. in-frame δcat mutants of c. diphtheriae and c. glutamicum were hyper-sensitive to growth inhibition and killing by h(2)o(2). in c. diphtheriae c7(β), both catalase activity and cat transcription decreased ~2-fold during transition from exponential growth to early stationary phase. prototypic oxyr in escherichia coli senses oxidative stress and it activates katg transcription and catalase produc ...201222438866
phenylacetic acid catabolism and its transcriptional regulation in corynebacterium glutamicum.the industrially important organism corynebacterium glutamicum has been characterized in recent years for its robust ability to assimilate aromatic compounds. in this study, c. glutamicum strain as 1.542 was investigated for its ability to catabolize phenylacetic acid (paa). the paa genes were identified; they are organized as a continuous paa gene cluster. the type strain of c. glutamicum, atcc 13032, is not able to catabolize paa, but the recombinant strain atcc 13032/pec-k18mob2::paa gained t ...201222685150
altered large-ring cyclodextrin product profile due to a mutation at tyr-172 in the amylomaltase of corynebacterium glutamicum.corynebacterium glutamicum amylomaltase (cgam) catalyzes the formation of large-ring cyclodextrins (lr-cds) with a degree of polymerization of 19 and higher. the cloned cgam gene was ligated into the pet-17b vector and used to transform escherichia coli bl21(de3). site-directed mutagenesis of tyr-172 in cgam to alanine (y172a) was performed to determine its role in the control of lr-cd production. both the recombinant wild-type (wt) and y172a enzymes were purified to apparent homogeneity and cha ...201222865069
complete genome sequence, lifestyle, and multi-drug resistance of the human pathogen corynebacterium resistens dsm 45100 isolated from blood samples of a leukemia patient.corynebacterium resistens was initially recovered from human infections and recognized as a new coryneform species that is highly resistant to antimicrobial agents. bacteremia associated with this organism in immunocompromised patients was rapidly fatal as standard minocycline therapies failed. c. resistens dsm 45100 was isolated from a blood culture of samples taken from a patient with acute myelocytic leukemia. the complete genome sequence of c. resistens dsm 45100 was determined by pyrosequen ...201222524407
accelerated pentose utilization by corynebacterium glutamicum for accelerated production of lysine, glutamate, ornithine and putrescine.because of their abundance in hemicellulosic wastes arabinose and xylose are an interesting source of carbon for biotechnological production processes. previous studies have engineered several corynebacterium glutamicum strains for the utilization of arabinose and xylose, however, with inefficient xylose utilization capabilities. to improve xylose utilization, different xylose isomerase genes were tested in c. glutamicum. the gene originating from xanthomonas campestris was shown to have the hig ...201223164409
identification and characterization of γ-aminobutyric acid uptake system gabpcg (ncgl0464) in corynebacterium glutamicum.corynebacterium glutamicum is widely used for industrial production of various amino acids and vitamins, and there is growing interest in engineering this bacterium for more commercial bioproducts such as γ-aminobutyric acid (gaba). in this study, a c. glutamicum gaba-specific transporter (gabp(cg)) encoded by ncgl0464 was identified and characterized. gabp(cg) plays a major role in gaba uptake and is essential to c. glutamicum growing on gaba. gaba uptake by gabp(cg) was weakly competed by l-as ...201222307305
metabolic engineering of corynebacterium glutamicum aimed at alternative carbon sources and new products.corynebacterium glutamicum is well known as the amino acid-producing workhorse of fermentation industry, being used for multi-million-ton scale production of glutamate and lysine for more than 60 years. however, it is only recently that extensive research has focused on engineering it beyond the scope of amino acids. meanwhile, a variety of corynebacterial strains allows access to alternative carbon sources and/or allows production of a wide range of industrially relevant compounds. some of thes ...201224688664
reductive whole-cell biotransformation with corynebacterium glutamicum: improvement of nadph generation from glucose by a cyclized pentose phosphate pathway using pfka and gapa deletion mutants.in this study, the potential of corynebacterium glutamicum for reductive whole-cell biotransformation is shown. the nadph-dependent reduction of the prochiral methyl acetoacetate (maa) to the chiral (r)-methyl 3-hydroxybutyrate (mhb) by an alcohol dehydrogenase from lactobacillus brevis (lbadh) was used as model reaction and glucose served as substrate for the regeneration of nadph. since nadph is mainly formed in the oxidative branch of the pentose phosphate pathway (ppp), c. glutamicum was eng ...201222851018
overexpression of genes encoding glycolytic enzymes in corynebacterium glutamicum enhances glucose metabolism and alanine production under oxygen deprivation conditions.we previously reported that corynebacterium glutamicum strain δldhaδppc+alad+gapa, overexpressing glyceraldehyde-3-phosphate dehydrogenase-encoding gapa, shows significantly improved glucose consumption and alanine formation under oxygen deprivation conditions (t. jojima, m. fujii, e. mori, m. inui, and h. yukawa, appl. microbiol. biotechnol. 87:159-165, 2010). in this study, we employ stepwise overexpression and chromosomal integration of a total of four genes encoding glycolytic enzymes (herei ...201222504802
an in silico platform for the design of heterologous pathways in nonnative metabolite production.microorganisms are used as cell factories to produce valuable compounds in pharmaceuticals, biofuels, and other industrial processes. incorporating heterologous metabolic pathways into well-characterized hosts is a major strategy for obtaining these target metabolites and improving productivity. however, selecting appropriate heterologous metabolic pathways for a host microorganism remains difficult owing to the complexity of metabolic networks. hence, metabolic network design could benefit grea ...201222578364
application of den refinement and automated model building to a difficult case of molecular-replacement phasing: the structure of a putative succinyl-diaminopimelate desuccinylase from corynebacterium glutamicum.phasing by molecular replacement remains difficult for targets that are far from the search model or in situations where the crystal diffracts only weakly or to low resolution. here, the process of determining and refining the structure of cgl1109, a putative succinyl-diaminopimelate desuccinylase from corynebacterium glutamicum, at ∼3 å resolution is described using a combination of homology modeling with modeller, molecular-replacement phasing with phaser, deformable elastic network (den) refi ...201222505259
carotenoid biosynthesis and overproduction in corynebacterium glutamicum.corynebacterium glutamicum contains the glycosylated c50 carotenoid decaprenoxanthin as yellow pigment. starting from isopentenyl pyrophosphate, which is generated in the non-mevalonate pathway, decaprenoxanthin is synthesized via the intermediates farnesyl pyrophosphate, geranylgeranyl pyrophosphate, lycopene and flavuxanthin.201222963379
extensive exometabolome analysis reveals extended overflow metabolism in various microorganisms.overflow metabolism is well known for yeast, bacteria and mammalian cells. it typically occurs under glucose excess conditions and is characterized by excretions of by-products such as ethanol, acetate or lactate. this phenomenon, also denoted the short-term crabtree effect, has been extensively studied over the past few decades, however, its basic regulatory mechanism and functional role in metabolism is still unknown. here we present a comprehensive quantitative and time-dependent analysis of ...201222963408
glycerol-3-phosphatase of corynebacterium glutamicum.formation of glycerol as by-product of amino acid production by corynebacterium glutamicum has been observed under certain conditions, but the enzyme(s) involved in its synthesis from glycerol-3-phosphate were not known. it was shown here that cg1700 encodes an enzyme active as a glycerol-3-phosphatase (gpp) hydrolyzing glycerol-3-phosphate to inorganic phosphate and glycerol. gpp was found to be active as a homodimer. the enzyme preferred conditions of neutral ph and requires mg²⁺ or mn²⁺ for i ...201222353596
conservation of structure and mechanism within the transaldolase enzyme family.transaldolase (tal) is involved in the central carbon metabolism, i.e. the non-oxidative pentose phosphate pathway, and is therefore a ubiquitous enzyme. however, tals show a low degree in sequence identity and vary in length within the enzyme family which previously led to the definition of five subfamilies. we wondered how this variation is conserved in structure and function. to answer this question we characterised and compared the tals from bacillus subtilis, corynebacterium glutamicum and ...201222212631
quantitation of intracellular purine intermediates in different corynebacteria using electrospray lc-ms/ms.intermediates of the purine biosynthesis pathway play key roles in cellular metabolism including nucleic acid synthesis and signal mediation. in addition, they are also of major interest to the biotechnological industry as several intermediates either possess flavor-enhancing characteristics or are applied in medical therapy. in this study, we have developed an analytical method for quantitation of 12 intermediates from the purine biosynthesis pathway including important nucleotides and their co ...201222960872
design and testing of a synthetic biology framework for genetic engineering of corynebacterium glutamicum.synthetic biology approaches can make a significant contribution to the advance of metabolic engineering by reducing the development time of recombinant organisms. however, most of synthetic biology tools have been developed for escherichia coli. here we provide a platform for rapid engineering of c. glutamicum, a microorganism of great industrial interest. this bacteria, used for decades for the fermentative production of amino acids, has recently been developed as a host for the production of ...201223134565
model-based analysis of an adaptive evolution experiment with escherichia coli in a pyruvate limited continuous culture with glycerol.: bacterial strains that were genetically blocked in important metabolic pathways and grown under selective conditions underwent a process of adaptive evolution: certain pathways may have been deregulated and therefore allowed for the circumvention of the given block. a block of endogenous pyruvate synthesis from glycerol was realized by a knockout of pyruvate kinase and phosphoenolpyruvate carboxylase in e. coli. the resulting mutant strain was able to grow on a medium containing glycerol and l ...201223033959
[construction and structural analysis of integrated cellular network of corynebacterium glutamicum].corynebacterium glutamicum is one of the most important traditional industrial microorganisms and receiving more and more attention towards a novel cellular factory due to the recently rapid development in genomics and genetic operation toolboxes for corynebacterium. however, compared to other model organisms such as escherichia coli, there were few studies on its metabolic regulation, especially a genome-scale integrated cellular network model currently missing for corynebacterium, which hinder ...201222916496
construction of in vitro transcription system for corynebacterium glutamicum and its use in the recognition of promoters of different classes.to facilitate transcription studies in corynebacterium glutamicum, we have developed an in vitro transcription system for this bacterium used as an industrial producer of amino acids and a model organism for actinobacteria. this system consists of c. glutamicum rna polymerase (rnap) core (α2, β, β'), a sigma factor and a promoter-carrying dna template, that is specifically recognized by the rnap holoenzyme formed. the rnap core was purified from the c. glutamicum strain with the modified rpoc ge ...201222885668
characterization of the rna polymerase α subunit operon from corynebacterium ammoniagenes.the rpoa gene, which encodes the α subunit of rna polymerase, and the surrounding regions were cloned from corynebacterium ammoniagenes (atcc 6872), a parental strain of an industrial nucleotide producer in korea. this region encodes genes for the following proteins (in order): initiation factor if-1, the ribosomal proteins s13, s11 and s4, the α subunit of rna polymerase and the ribosomal protein l17. transcript mapping via reverse transcription polymerase chain reaction demonstrates that if1, ...201222806862
glutamate is excreted across the cytoplasmic membrane through the ncgl1221 channel of corynebacterium glutamicum by passive diffusion.the ncgl1221 gene, which encodes a mechanosensitive channel, has been reported to be critically involved in glutamate (glu) overproduction by corynebacterium glutamicum, but direct evidence of glu excretion through this channel has not yet been provided. in this study, by electrophysiological methods, we found direct evidence of glu excretion through this channel by passive diffusion. we found that the introduction into phe-producing escherichia coli of mutant ncgl1221 genes that induce glu over ...201222785475
co-expression of feedback-resistant threonine dehydratase and acetohydroxy acid synthase increase l-isoleucine production in corynebacterium glutamicum.threonine dehydratase and acetohydroxy acid synthase are critical enzymes in the l-isoleucine biosynthesis pathway of corynebacterium glutamicum, but their activities are usually feedback-inhibited. in this study, we characterized a feedback-resistant threonine dehydratase and an acetohydroxy acid synthase from an l-isoleucine producing strain c. glutamicum jhi3-156. sequence analysis showed that there was only a single amino acid substitution (phe383val) in the feedback-resistant threonine dehy ...201222771937
robust production of gamma-amino butyric acid using recombinant corynebacterium glutamicum expressing glutamate decarboxylase from escherichia coli.gamma-amino butyric acid (gaba) is a component of pharmaceuticals, functional foods, and the biodegradable plastic polyamide 4. here, we report a simple and robust system to produce gaba from glucose using the recombinant corynebacterium glutamicum strain gad, which expresses gadb, a glutamate decarboxylase encoded by the gadb gene of escherichia coli w3110. as confirmed by hplc analysis, gaba fermentation by c. glutamicum gad cultured at 30°c in gaba production 1 (gp1) medium containing 50 g/l ...201222759537
development and application of an arabinose-inducible expression system by facilitating inducer uptake in corynebacterium glutamicum.corynebacterium glutamicum is currently used for the industrial production of a variety of biological materials. many available inducible expression systems in this species use lac-derived promoters from escherichia coli that exhibit much lower levels of inducible expression and leaky basal expression. we developed an arabinose-inducible expression system that contains the l-arabinose regulator arac, the p(bad) promoter from the arabad operon, and the l-arabinose transporter arae, all of which a ...201222685153
improved detection of microbial risk of releasing genetically modified bacteria in soil by using massive sequencing and antibiotic resistance selection.high-throughput 16s rrna gene-targeted pyrosequencing was used with commonly used risk assessment techniques to evaluate the potential microbial risk in soil after inoculating genetically modified (gm) corynebacterium glutamicum. to verify the risk, reference experiments were conducted in parallel using well-defined and frequently used gm escherichia coli and wild-type strains. the viable cell count showed that the number of gm bacteria in the soil was reduced to below the detection limit within ...201222682799
a high-throughput approach to identify genomic variants of bacterial metabolite producers at the single-cell level.we present a novel method for visualizing intracellular metabolite concentrations within single cells of escherichia coli and corynebacterium glutamicum that expedites the screening process of producers. it is based on transcription factors and we used it to isolate new l-lysine producing mutants of c. glutamicum from a large library of mutagenized cells using fluorescence-activated cell sorting (facs). this high-throughput method fills the gap between existing high-throughput methods for mutant ...201222640862
comparative reaction engineering studies for succinic acid production from sucrose by metabolically engineered escherichia coli in fed-batch-operated stirred tank bioreactors.this study presents a comparative reaction engineering analysis of metabolically engineered sucrose-utilizing escherichia coli derived from e. coli k12 mg1655 for the anaerobic production of succinic acid. production capacities of 16 different recombinant strains were evaluated in 48 parallel fed-batch-operated milliliter-scale stirred tank bioreactors (10 ml) with continuous co₂ sparging. the effects of recombinant sucrose-utilization systems (csc-operon or scr-operon), enhancements of anaplero ...201222588847
[a novel bacterial cell-surface display system based on ncgl1221 from corynebacterium glutamicum].to develop a novel escherichia coli cell surface display system by using c-terminally truncated ncgl1221 as the anchoring protein, which greatly enriched or optimized the bacterial displayed systems.201222586995
a disposable picolitre bioreactor for cultivation and investigation of industrially relevant bacteria on the single cell level.in the continuously growing field of industrial biotechnology the scale-up from lab to industrial scale is still a major hurdle to develop competitive bioprocesses. during scale-up the productivity of single cells might be affected by bioreactor inhomogeneity and population heterogeneity. currently, these complex interactions are difficult to investigate. in this report, design, fabrication and operation of a disposable picolitre cultivation system is described, in which environmental conditions ...201222511122
the missing link in coenzyme a biosynthesis: panm (formerly yhhk), a yeast gcn5 acetyltransferase homologue triggers aspartate decarboxylase (pand) maturation in salmonella enterica.coenzyme a (coa) is an essential cofactor for all forms of life. the biochemistry underpinning the assembly of coa in escherichia coli and other enterobacteria is well understood, except for the events leading to maturation of the l-aspartate-α-decarboxylase (pand) enzyme that converts pantothenate to β-alanine. pand is synthesized as pro-pand, which undergoes an auto-proteolytic cleavage at residue ser25 to yield the catalytic pyruvoyl moiety of the enzyme. since 1990, it has been known that e. ...201222497218
preliminary investigations of the effect of lipophilic analogues of the active metabolite of isoniazid toward bacterial and plasmodial strains.five lipophilic analogues 1-5 of the active metabolite of the antitubercular drug isoniazid (inh), selected as inhibitors of mycobacterium smegmatis and mycobacterium tuberculosis growth, were evaluated for their activity against corynebacterium glutamicum (lacking in inha activity), escherichia coli (to test mycobacteria selectivity), and plasmodium falciparum (as possible parasite target). compound 3 was the only one that did not inhibit c. glutamicum growth. the poor inha inhibitors 1 and 2 w ...201222405039
improving putrescine production by corynebacterium glutamicum by fine-tuning ornithine transcarbamoylase activity using a plasmid addiction system.corynebacterium glutamicum shows a great potential for the production of the polyamide monomer putrescine (1,4-diaminobutane). previously, we constructed the putrescine-producing strain put1 by deletion of argf, the gene for ornithine transcarbamoylase (otc), and argr, encoding the l-arginine repressor, combined with heterologous expression of the escherichia coli gene for l-ornithine decarboxylase spec. as a consequence of argf deletion, this strain requires supplementation of l-arginine and sh ...201222370950
a synthetic escherichia coli system identifies a conserved origin tethering factor in actinobacteria.in eukaryotic and prokaryotic cells the establishment and maintenance of cell polarity is essential for numerous biological processes. in some bacterial species, the chromosome origins have been identified as molecular markers of cell polarity and polar chromosome anchoring factors have been identified, for example in caulobacter crescentus. although speculated, polar chromosome tethering factors have not been identified for actinobacteria, to date. here, using a minimal synthetic escherichia co ...201222340668
an automated workflow for enhancing microbial bioprocess optimization on a novel microbioreactor platform.high-throughput methods are widely-used for strain screening effectively resulting in binary information regarding high or low productivity. nevertheless achieving quantitative and scalable parameters for fast bioprocess development is much more challenging, especially for heterologous protein production. here, the nature of the foreign protein makes it impossible to predict the, e.g. best expression construct, secretion signal peptide, inductor concentration, induction time, temperature and sub ...201223113930
chemometric formulation of bacterial consortium-avs for improved decolorization of resonance-stabilized and heteropolyaromatic dyes.a bacterial consortium-avs, consisting of pseudomonas desmolyticum ncim 2112, kocuria rosea mtcc 1532 and micrococcus glutamicus ncim 2168 was formulated chemometrically, using the mixture design matrix based on the design of experiments methodology. the formulated consortium-avs decolorized acid blue 15 and methylene blue with a higher average decolorization rate, which is more rapid than that of the pure cultures. the uv-vis spectrophotometric, fourier transform infra red spectrophotometric an ...201222940340
mmpl genes are associated with mycolic acid metabolism in mycobacteria and corynebacteria.mycolic acids are vital components of the cell wall of the tubercle bacillus mycobacterium tuberculosis and are required for viability and virulence. while mycolic acid biosynthesis is studied extensively, components involved in mycolate transport remain unidentified. we investigated the role of large membrane proteins encoded by mmpl genes in mycolic acid transport in mycobacteria and the related corynebacteria. mmpl3 was found to be essential in mycobacteria and conditional depletion of mmpl3 ...201222520756
differential arabinan capping of lipoarabinomannan modulates innate immune responses and impacts t helper cell differentiation.toll-like receptors (tlrs) recognize pathogens by interacting with pathogen-associated molecular patterns, such as the phosphatidylinositol-based lipoglycans, lipomannan (lm) and lipoarabinomannan (lam). such structures are present in several pathogens, including mycobacterium tuberculosis, being important for the initiation of immune responses. it is well established that the interaction of lm and lam with tlr2 is a process dependent on the structure of the ligands. however, the implications of ...201223144457
the lipoprotein lpqw is essential for the mannosylation of periplasmic glycolipids in corynebacteria.phosphatidylinositol mannosides (pim), lipomannan (lm), and lipoarabinomannan (lam) are essential components of the cell wall and plasma membrane of mycobacteria, including the human pathogen mycobacterium tuberculosis, as well as the related corynebacterineae. we have previously shown that the lipoprotein, lpqw, regulates pim and lm/lam biosynthesis in mycobacteria. here, we provide direct evidence that lpqw regulates the activity of key mannosyltransferases in the periplasmic leaflet of the ce ...201223091062
deletion of manc in corynebacterium glutamicum results in a phospho-myo-inositol mannoside- and lipoglycan-deficient mutant.mannose is an important constituent of the immunomodulatory glycoconjugates of the mycobacterial cell wall: lipoarabinomannan (lam), lipomannan (lm) and the related phospho-myo-inositol mannosides (pims). in mycobacterium tuberculosis and the related bacillus corynebacterium glutamicum, mannose is either imported from the medium or derived from glycolysis, and is subsequently converted into the nucleotide-based sugar donor guanosine diphosphomannose (gdp-mannose). this can be utilized by the gly ...201222539165
growth response of avena sativa in amino-acids-rich soils converted from phenol-contaminated soils by corynebacterium glutamicum.the biodegradation of phenol in laboratory-contaminated soil was investigated using the gram-positive soil bacterium corynebacterium glutamicum. this study showed that the phenol degradation caused by c. glutamicum was greatly enhanced by the addition of 1% yeast extract. from the toxicity test using daphnia magna, the soil did not exhibit any hazardous effects after the phenol was removed using c. glutamicum. additionally, the treatment of the phenolcontaminated soils with c. glutamicum increas ...201222534303
next-generation sequencing-based genome-wide mutation analysis of l-lysine-producing corynebacterium glutamicum atcc 21300 strain.in order to identify single nucleotide polymorphism and insertion/deletion mutations, we performed whole-genome re-sequencing of the enhanced l-lysine-producing corynebacterium glutamicum atcc 21300 strain. in total, 142 single nucleotide polymorphisms and 477 insertion/deletion mutations were identified in the atcc 21300 strain when compared to 3,434 predicted genes of the wild-type c. glutamicum atcc 13032 strain. among them, 110 transitions and 29 transversions of single nucleotide polymorphi ...201223124757
identification of a had superfamily phosphatase, hdpa, involved in 1,3-dihydroxyacetone production during sugar catabolism in corynebacterium glutamicum.corynebacterium glutamicum produces 1,3-dihydroxyacetone (dha) as metabolite of sugar catabolism but the responsible enzyme is yet to be identified. using a transposon mutant library, the gene hdpa (cgr_2128) was shown to encode a haloacid dehalogenase superfamily member that catalyzes dephosphorylation of dihydroxyacetone phosphate to produce dha. inactivation of hdpa led to a drastic decrease in dha production from each of glucose, fructose, and sucrose, indicating that hdpa is the main enzyme ...201223108048
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