| recombineering using recet in corynebacterium glutamicum atcc14067 via a self-excisable cassette. | gene manipulation is essential for metabolic engineering and synthetic biology, but the current general gene manipulation methods are not applicable to the non-model strain corynebacterium glutamicum (c. glutamicum) atcc14067, which is used for amino acid production. here, we report an effective and sequential deletion method for c. glutamicum atcc14067 using the exonuclease-recombinase pair rece + rect (recet) for recombineering via a designed self-excisable linear double-strand dna (dsdna) cas ... | 2017 | 28801604 |
| physiological roles of sigma factor sigd in corynebacterium glutamicum. | sigma factors are one of the components of rna polymerase holoenzymes, and an essential factor of transcription initiation in bacteria. corynebacterium glutamicum possesses seven genes coding for sigma factors, most of which have been studied to some detail; however, the role of sigd in transcriptional regulation in c. glutamicum has been mostly unknown. | 2017 | 28701150 |
| development of a single-cell glxr-based camp biosensor for corynebacterium glutamicum. | cyclic adenosine monophosphate (camp) plays a regulatory role as second messenger in many species. in the industrial model organism corynebacterium glutamicum, camp acts as effector of the global transcriptional regulator glxr, a homolog of enterobacterial crp. the camp-glxr complex activates or represses the expression of about 200 target genes. cyab, a membrane-bound class iii adenylate cyclase, synthesizes camp from atp, but another yet unknown camp-forming enzyme is likely present in c. glut ... | 2017 | 28698098 |
| a new genome-scale metabolic model of corynebacterium glutamicum and its application. | corynebacterium glutamicum is an important platform organism for industrial biotechnology to produce amino acids, organic acids, bioplastic monomers, and biofuels. the metabolic flexibility, broad substrate spectrum, and fermentative robustness of c. glutamicum make this organism an ideal cell factory to manufacture desired products. with increases in gene function, transport system, and metabolic profile information under certain conditions, developing a comprehensive genome-scale metabolic mod ... | 2017 | 28680478 |
| structural insights into substrate specificity of cystathionine γ-synthase from corynebacterium glutamicum. | cystathionine γ-synthase (metb) condenses o-acetyl-l-homoserine (oahs) or o-succinyl-l-homoserine (oshs) with cysteine to produce cystathionine. to investigate the molecular mechanisms and substrate specificity of metb from corynebacterium glutamicum (cgmetb), we determined its crystal structure at 1.5 å resolution. the pyridoxal phosphate cofactor is covalently bound to lys204 via a schiff base linkage in the deep cavity. superposition with the structure of metb from nicotiana tabacum in comple ... | 2017 | 28675039 |
| assignment of sigma factors of rna polymerase to promoters in corynebacterium glutamicum. | corynebacterium glutamicum is an important industrial producer of various amino acids and other metabolites. the c. glutamicum genome encodes seven sigma subunits (factors) of rna polymerase: the primary sigma factor siga (σ(a)), the primary-like σ(b) and five alternative sigma factors (σ(c), σ(d), σ(e), σ(h) and σ(m)). we have developed in vitro and in vivo methods to assign particular sigma factors to individual promoters of different classes. in vitro transcription assays and measurements of ... | 2017 | 28651382 |
| crispr/cas9-coupled recombineering for metabolic engineering of corynebacterium glutamicum. | genome engineering of corynebacterium glutamicum, an important industrial microorganism for amino acids production, currently relies on random mutagenesis and inefficient double crossover events. here we report a rapid genome engineering strategy to scarlessly knock out one or more genes in c. glutamicum in sequential and iterative manner. recombinase rect is used to incorporate synthetic single-stranded oligodeoxyribonucleotides into the genome and crispr/cas9 to counter-select negative mutants ... | 2017 | 28649005 |
| the linkage between nutrient supply, intracellular enzyme abundances and bacterial growth: new evidences from the central carbon metabolism of corynebacterium glutamicum. | corynebacterium glutamicum serves as important production host for small molecular compounds that are derived from precursor molecules of the central carbon metabolism. it is therefore a well-studied model organism of industrial biotechnology. however, a deeper understanding of the regulatory principles underlying the synthesis of central metabolic enzymes under different environmental conditions as well as its impact on cell growth is still missing. we studied enzyme abundances in c. glutamicum ... | 2017 | 28647528 |
| biotransformation of ferulic acid to protocatechuic acid by corynebacterium glutamicum atcc 21420 engineered to express vanillate o-demethylase. | ferulic acid (4-hydroxy-3-methoxycinnamic acid, fa) is a lignin-derived phenolic compound abundant in plant biomass. the utilization of fa and its conversion to valuable compounds is desired. protocatechuic acid (3,4-dihydroxybenzoic acid, pca) is a precursor of polymers and plastics and a constituent of food. a microbial conversion system to produce pca from fa was developed in this study using a pca-producing strain of corynebacterium glutamicum f (atcc 21420). c. glutamicum strain f grown at ... | 2017 | 28641405 |
| selective oxidation of aliphatic c-h bonds in alkylphenols by a chemomimetic biocatalytic system. | selective oxidation of aliphatic c-h bonds in alkylphenols serves significant roles not only in generation of functionalized intermediates that can be used to synthesize diverse downstream chemical products, but also in biological degradation of these environmentally hazardous compounds. chemo-, regio-, and stereoselectivity; controllability; and environmental impact represent the major challenges for chemical oxidation of alkylphenols. here, we report the development of a unique chemomimetic bi ... | 2017 | 28607077 |
| enhancement of anaerobic lysine production in corynebacterium glutamicum electrofermentations. | it has been suggested that application of electric potential can affect lysine producing fermentations, although experimental evidence is lacking. to study this hypothesis we used the lysine producer corynebacterium glutamicum zw04, and we exposed it to 12 different conditions regarding anaerobic gas environment, applied electrode potential (cathodic, open circuit, anodic), redox mediator and nitrate presence. the gas environment was found to play a major role, with co2 leading to double the lys ... | 2017 | 28599233 |
| novel chromosome organization pattern in actinomycetales-overlapping replication cycles combined with diploidy. | bacteria regulate chromosome replication and segregation tightly with cell division to ensure faithful segregation of dna to daughter generations. the underlying mechanisms have been addressed in several model species. it became apparent that bacteria have evolved quite different strategies to regulate dna segregation and chromosomal organization. we have investigated here how the actinobacterium corynebacterium glutamicum organizes chromosome segregation and dna replication. unexpectedly, we fo ... | 2017 | 28588128 |
| metabolic design of corynebacterium glutamicum for production of l-cysteine with consideration of sulfur-supplemented animal feed. | l-cysteine is a valuable sulfur-containing amino acid widely used as a nutrition supplement in industrial food production, agriculture, and animal feed. however, this amino acid is mostly produced by acid hydrolysis and extraction from human or animal hairs. in this study, we constructed recombinant corynebacterium glutamicum strains that overexpress combinatorial genes for l-cysteine production. the aims of this work were to investigate the effect of the combined overexpression of serine acetyl ... | 2017 | 28560868 |
| miniaturized and automated adaptive laboratory evolution: evolving corynebacterium glutamicum towards an improved d-xylose utilization. | adaptive laboratory evolution (ale) is increasingly being used as a technique for untargeted strain optimization. this work aimed at developing an automated and miniaturized ale approach based on repetitive batch cultivations in microtiter plates. the new method is applied to the recently published strain corynebacterium glutamicum pekex3-xylxabcdcc, which is capable of utilizing d-xylose via the weimberg (wmb) pathway. as a result, the significantly improved strain wmb2evo was obtained, showing ... | 2017 | 28552568 |
| enhancement of 5-aminolevulinic acid production by metabolic engineering of the glycine biosynthesis pathway in corynebacterium glutamicum. | to construct a strain of corynebacterium glutamicum capable of efficiently producing 5-aminolevulinic acid (5-ala) via the c4 pathway by modification of serine and glycine pathway using glucose as sole carbon source. | 2017 | 28536938 |
| overexpression of ppc or deletion of mdh for improving production of γ-aminobutyric acid in recombinant corynebacterium glutamicum. | l-glutamate decarboxylase (gad) transforms l-glutamate into γ-aminobutyric acid (gaba). corynebacterium glutamicum that expresses exogenous gad gene(s) can synthesize gaba from its own produced l-glutamate. to enhance gaba production in recombinant c. glutamicum strain sh, metabolic engineering strategies were used to improve the supply of the gaba precursor, l-glutamate. five new strains were constructed here. first, the ppc gene was coexpressed with two gad genes (gadb1 and gadb2). then, the m ... | 2017 | 28534111 |
| y418 in 410s loop is required for high transglucosylation activity and large-ring cyclodextrin production of amylomaltase from corynebacterium glutamicum. | amylomaltase catalyzes α-1,4 glucosyl transfer reaction to yield linear or cyclic oligosaccharide products. the aim of this work is to investigate functional roles of 410s loop unique to amylomaltase from corynebacterium glutamicum (cgam). site-directed mutagenesis of y418, the residue at the loop tip, was performed. y418a/s/d/r/w/f - cgams were characterized and compared to the wild-type (wt). a significant decrease in starch transglucosylation, disproportionation and cyclization activities was ... | 2017 | 28522291 |
| crystal structure of the 2-iminoglutarate-bound complex of glutamate dehydrogenase from corynebacterium glutamicum. | the nadp(+) -dependent glutamate dehydrogenase from corynebacterium glutamicum (cggdh) is considered to be one of the key enzymes in the industrial fermentation of glutamate due to its high glutamate-producing activity. we determined the crystal structure of cggdh complexed with nadp(+) and 2-iminoglutarate. among six subunits of hexameric cggdh-binding nadp(+) , only four subunits bind 2-iminoglutarate in a closed form, while the other two are in an open form. in the closed form, 2-iminoglutara ... | 2017 | 28486765 |
| isoprenoid pyrophosphate-dependent transcriptional regulation of carotenogenesis in corynebacterium glutamicum. | corynebacterium glutamicum is a natural producer of the c50 carotenoid decaprenoxanthin. the crtecg0722crtbiyeb operon comprises most of its genes for terpenoid biosynthesis. the marr-type regulator encoded upstream and in divergent orientation of the carotenoid biosynthesis operon has not yet been characterized. this regulator, named crtr in this study, is encoded in many actinobacterial genomes co-occurring with terpenoid biosynthesis genes. crtr was shown to repress the crt operon of c. gluta ... | 2017 | 28484430 |
| improved fermentative production of the compatible solute ectoine by corynebacterium glutamicum from glucose and alternative carbon sources. | the cyclic amino acid ectoine is a compatible solute serving as a protective substance against osmotic stress. ectoine finds various applications due to its moisturizing effect. to avoid the disadvantages of the prevailing so-called "bacterial milking ectoine production process" caused by the high salt concentration, low salt fermentation strategies are sought after. as l-lysine and ectoine biosynthesis share l-aspartate-semialdehyde as common precursor, l-lysine producing strains can be convert ... | 2017 | 28478080 |
| complete nucleotide sequence and annotation of the temperate corynephage ϕ16 genome. | the complete genome of ϕ16, a temperate corynephage from corynebacterium glutamicum atcc 21792, was sequenced and annotated (genbank: ky250482). the electron microscopy study of ϕ16 virion confirmed that it belongs to the family siphoviridae. the ϕ16 genome consists of a linear double-stranded dna molecule of 58,200 bp (g+c = 52.2%) with protruding cohesive 3'-ends of 14 nt. four major structural proteins were separated by sds-page and identified by peptide mass fingerprinting technique. using b ... | 2017 | 28455670 |
| the arsenic detoxification system in corynebacteria: basis and application for bioremediation and redox control. | arsenic (as) is widespread in the environment and highly toxic. it has been released by volcanic and anthropogenic activities and causes serious health problems worldwide. to survive arsenic-rich environments, soil and saprophytic microorganisms have developed molecular detoxification mechanisms to survive arsenic-rich environments, mainly by the enzymatic conversion of inorganic arsenate (as(v)) to arsenite (as(iii)) by arsenate reductases, which is then extruded by arsenite permeases. one of t ... | 2017 | 28438267 |
| genome-wide determination of transcription start sites reveals new insights into promoter structures in the actinomycete corynebacterium glutamicum. | the genome-wide identification of transcription start sites, enabled by high-throughput sequencing of a cdna library enriched for native 5' transcript ends, is ideally suited for the analysis of promoters. here, the transcriptome of corynebacterium glutamicum, a non-pathogenic soil bacterium from the actinomycetes branch that is used in industry for the production of amino acids, was analysed by transcriptome sequencing of the 5'-ends of native transcripts. total rna samples were harvested from ... | 2017 | 28412515 |
| dynamic flux balance analysis with nonlinear objective function. | dynamic flux balance analysis (dfba) extends flux balance analysis and enables the combined simulation of both intracellular and extracellular environments of microbial cultivation processes. a dfba model contains two coupled parts, a dynamic part at the upper level (extracellular environment) and an optimization part at the lower level (intracellular environment). both parts are coupled through substrate uptake and product secretion rates. this work proposes a karush-kuhn-tucker condition based ... | 2017 | 28401266 |
| analysis of strain-specific genes in glutamic acid-producing corynebacterium glutamicum ssp. lactofermentum aj 1511. | strains of the bacterium, corynebacterium glutamicum, are widely used for the industrial production of l-glutamic acid and various other substances. c. glutamicum ssp. lactofermentum aj 1511, formerly classified as brevibacterium lactofermentum, and the closely related c. glutamicum atcc 13032 have been used as industrial strains for more than 50 years. we determined the whole genome sequence of c. glutamicum aj 1511 and performed genome-wide comparative analysis with c. glutamicum atcc 13032 to ... | 2017 | 28392541 |
| identification of specific posttranslational o-mycoloylations mediating protein targeting to the mycomembrane. | the outer membranes (oms) of members of the corynebacteriales bacterial order, also called mycomembranes, harbor mycolic acids and unusual outer membrane proteins (omps), including those with α-helical structure. the signals that allow precursors of such proteins to be targeted to the mycomembrane remain uncharacterized. we report here the molecular features responsible for omp targeting to the mycomembrane of corynebacterium glutamicum, a nonpathogenic member of the corynebacteriales order. to ... | 2017 | 28373551 |
| transcriptome analysis of corynebacterium glutamicum in the process of recombinant protein expression in bioreactors. | corynebacterium glutamicum (c. glutamicum) is a favorable host cell for the production of recombinant proteins, such as important enzymes and pharmaceutical proteins, due to its excellent potential advantages. herein, we sought to systematically explore the influence of recombinant protein expression on the transcription and metabolism of c. glutamicum. two c. glutamicum strains, the wild-type strain and an engineered strain expressing enhanced green fluorescent protein (egfp), were cultured in ... | 2017 | 28369109 |
| a novel genetic tool for metabolic optimization of corynebacterium glutamicum: efficient and repetitive chromosomal integration of synthetic promoter-driven expression libraries. | fine-tuning the expression level of multiple genes is usually pivotal for metabolic optimization. we have developed a tool for this purpose for the important industrial workhorse corynebacterium glutamicum that allows for the introduction of synthetic promoter-driven expression libraries of arbitrary genes. we first devised a method for introducing genetic elements into the chromosome repeatedly, relying on site-specific recombinases and the vector pjs31 serving as the carrier. the pjs31 vector ... | 2017 | 28361238 |
| a newly determined member of the meso-diaminopimelate dehydrogenase family with a broad substrate spectrum. | meso-diaminopimelate dehydrogenase (meso-dapdh) from symbiobacterium thermophilum (stdapdh) is the first member of the meso-dapdh family known to catalyze the asymmetric reductive amination of 2-keto acids to produce d-amino acids. it is important to understand the catalytic mechanisms of stdapdh and other enzymes in this family. in this study, based on an evolutionary analysis and examination of catalytic activity, the meso-dapdh enzymes can be divided into two types. type i showed highly prefe ... | 2017 | 28341677 |
| proteomics of facs-sorted heterogeneous corynebacterium glutamicum populations. | the metabolic status of individual cells in microbial cultures can differ, being relevant for biotechnology, environmental and medical microbiology. however, it is hardly understood in molecular detail due to limitations of current analytical tools. here, we demonstrate that facs in combination with proteomics can be used to sort and analyze cell populations based on their metabolic state. a previously established gfp reporter system was used to detect and sort single corynebacterium glutamicum ... | 2017 | 28323243 |
| similarities in the structure of the transcriptional repressor amtr in two different space groups suggest a model for the interaction with glnk. | amtr belongs to the tetr family of transcription regulators and is a global nitrogen regulator that is induced under nitrogen-starvation conditions in corynebacterium glutamicum. amtr regulates the expression of transporters and enzymes for the assimilation of ammonium and alternative nitrogen sources, for example urea, amino acids etc. the recognition of operator dna by homodimeric amtr is not regulated by small-molecule effectors as in other tetr-family members but by a trimeric adenylylated p ... | 2017 | 28291750 |
| characterization of lysine acetylation of a phosphoenolpyruvate carboxylase involved in glutamate overproduction in corynebacterium glutamicum. | protein nε-acylation is emerging as a ubiquitous post-translational modification. in corynebacterium glutamicum, which is utilized for industrial production of l-glutamate, the levels of protein acetylation and succinylation change drastically under the conditions that induce glutamate overproduction. here, the acylation of phosphoenolpyruvate carboxylase (pepc), an anaplerotic enzyme that supplies oxaloacetate for glutamate overproduction was characterized. it was shown that acetylation of pepc ... | 2017 | 28256782 |
| complete genome sequencing of newly isolated thermotolerant corynebacterium glutamicum n24 provides a new insights into its thermotolerant phenotype. | to understand the genetic background of thermotolerance, we determined the complete genome sequence of a thermotolerant corynebacterium glutamicum n24 strain isolated from soil. the whole genome based phylogenetic analysis between n24 and other related species revealed that n24 diverged from other c. glutamicum strains at earlier stages. comparisons of thermotolerance between n24 and its related species showed that n24 and corynebacterium efficiens ys-314 have a higher thermotolerance than coryn ... | 2017 | 28249784 |
| beyond amino acids: use of the corynebacterium glutamicum cell factory for the secretion of heterologous proteins. | the gram-positive soil bacterium corynebacterium glutamicum has a long tradition in industry as a potent cell factory for the production of various amino acids. besides this, in the last few years it became increasingly clear that this microorganism can also efficiently be used as a host organism for the expression and secretion of biotechnologically or pharmaceutically relevant heterologous proteins. in this review, first a short overview is given on the two main protein export pathways (sec an ... | 2017 | 28238807 |
| improvement of succinate production by release of end-product inhibition in corynebacterium glutamicum. | succinate is a renewable-based platform chemical that may be used to produce a wide range of chemicals including 1,4-butanediol, tetrahydrofurane, and γ-butyrolactone. however, industrial fermentation of organic acids is often subject to end-product inhibition, which significantly retards cell growth and limits metabolic activities and final productivity. in this study, we report the development of metabolically engineered corynebacterium glutamicum for high production of succinate by release of ... | 2017 | 28232033 |
| click-chemistry approach to study mycoloylated proteins: evidence for porb and porc porins mycoloylation in corynebacterium glutamicum. | protein mycoloylation is a recently identified, new form of protein acylation. this post-translational modification consists in the covalent attachment of mycolic acids residues to serine. mycolic acids are long chain, α-branched, β-hydroxylated fatty acids that are exclusively found in the cell envelope of corynebacteriales, a bacterial order that includes important genera such as mycobacterium, nocardia or corynebacterium. so far, only 3 mycoloylated proteins have been identified: pora, porh a ... | 2017 | 28199365 |
| comparative analysis of corynebacterium glutamicum genomes: a new perspective for the industrial production of amino acids. | corynebacterium glutamicum is a non-pathogenic bacterium widely used in industrial amino acid production and metabolic engineering research. although the genome sequences of some c. glutamicum strains are available, comprehensive comparative genome analyses of these species have not been done. six wild type c. glutamicum strains were sequenced using next-generation sequencing technology in our study. together with 20 previously reported strains, we present a comprehensive comparative analysis of ... | 2017 | 28198668 |
| cofactor recycling for co-production of 1,3-propanediol and glutamate by metabolically engineered corynebacterium glutamicum. | production of 1,3-propanediol (1,3-pdo) from glycerol is a promising route toward glycerol biorefinery. however, the yield of 1,3-pdo is limited due to the requirement of nadh regeneration via glycerol oxidation process, which generates large amounts of undesired byproducts. glutamate fermentation by corynebacterium glutamicum is an important oxidation process generating excess nadh. in this study, we proposed a novel strategy to couple the process of 1,3-pdo synthesis with glutamate production ... | 2017 | 28176878 |
| structural basis for redox sensitivity in corynebacterium glutamicum diaminopimelate epimerase: an enzyme involved in l-lysine biosynthesis. | diaminopimelate epimerase (dapf) is one of the crucial enzymes involved in l-lysine biosynthesis, where it converts l,l-diaminopimelate (l,l-dap) into d,l-dap. dapf is also considered as an attractive target for the development of antibacterial drugs. here, we report the crystal structure of dapf from corynebacterium glutamicum (cgdapf). structures of cgdapf obtained under both oxidized and reduced conditions reveal that the function of cgdapf is regulated by redox-switch modulation via reversib ... | 2017 | 28176858 |
| fermentative production of l-pipecolic acid from glucose and alternative carbon sources. | corynebacterium glutamicum is used for the million-ton scale production of amino acids and has recently been engineered for production of the cyclic non-proteinogenic amino acid l-pipecolic acid (l-pa). in this synthetic pathway l-lysine was converted to l-pa by oxidative deamination, dehydration and reduction by l-lysine 6-dehydrogenase (deaminating) from silicibacter pomeroyi and pyrroline 5-carboxylate reductase from c. glutamicum. however, production of l-pa occurred as by-product of l-lysin ... | 2017 | 28169491 |
| l-lysine production by bacillus methanolicus: genome-based mutational analysis and l-lysine secretion engineering. | bacillus methanolicus is a methylotrophic bacterium with an increasing interest in academic research and for biotechnological applications. this bacterium was previously applied for methanol-based production of l-glutamate, l-lysine and the five-carbon diamine cadaverine by wild type, classical mutant and recombinant strains. the genomes of two different l-lysine secreting b. methanolicus classical mutant strains, noa2#13a52-8a66 and m168-20, were sequenced. we focused on mutational mapping in g ... | 2017 | 28163092 |
| modular pathway engineering of corynebacterium glutamicum to improve xylose utilization and succinate production. | xylose-negative corynebacterium glutamicum has been engineered to utilize xylose as the sole carbon source via either the xylose isomerase (xi) pathway or the weimberg pathway. heterologous expression of xylose isomerase and overexpression of a gene encoding for xylulose kinase enabled efficient xylose utilization. in this study, we show that two functionally-redundant transcriptional regulators (gntr1 and gntr2) present on xylose repress the pentose phosphate pathway genes. for efficient xylose ... | 2017 | 28153765 |
| comprehensive and accurate tracking of carbon origin of lc-tandem mass spectrometry collisional fragments for (13)c-mfa. | in recent years the benefit of measuring positionally resolved (13)c-labeling enrichment from tandem mass spectrometry (ms/ms) collisional fragments for improved precision of (13)c-metabolic flux analysis ((13)c-mfa) has become evident. however, the usage of positional labeling information for (13)c-mfa faces two challenges: (1) the mass spectrometric acquisition of a large number of potentially interfering mass transitions may hamper accuracy and sensitivity. (2) the positional identity of carb ... | 2017 | 28116490 |
| pathway construction in corynebacterium glutamicum and strain engineering to produce rare sugars from glycerol. | rare sugars are valuable natural products widely used in pharmaceutical and food industries. in this study, we expected to synthesize rare ketoses from abundant glycerol using dihydroxyacetone phosphate (dhap)-dependent aldolases. first, a new glycerol assimilation pathway was constructed to synthesize dhap. the enzymes which convert glycerol to 3-hydroxypropionaldehyde and l-glyceraldehyde were selected, and their corresponding aldehyde synthesis pathways were constructed in vivo. four aldol pa ... | 2016 | 27998065 |
| metabolic engineering of cyanobacteria for the photosynthetic production of succinate. | succinate is an important commodity chemical currently used in the food, pharmaceutical, and polymer industries. it can also be chemically converted into other major industrial chemicals such as 1,4-butanediol, butadiene, and tetrahydrofuran. here we metabolically engineered a model cyanobacterium synechococcus elongatus pcc 7942 to photosynthetically produce succinate. we expressed the genes encoding for α-ketoglutarate decarboxylase and succinate semialdehyde dehydrogenase in s. elongatus pcc ... | 2016 | 27989804 |
| a novel synthetic pathway enables microbial production of polyphenols independent from the endogenous aromatic amino acid metabolism. | numerous plant polyphenols have potential applications as pharmaceuticals or nutraceuticals. stilbenes and flavonoids as most abundant polyphenols are synthesized from phenylpropanoids, which are exclusively derived from aromatic amino acids in nature. several microorganisms were engineered for the synthesis of biotechnologically interesting plant polyphenols; however, low activity of heterologous ammonia lyases, linking endogenous microbial aromatic amino acid biosynthesis to phenylpropanoid sy ... | 2017 | 27936616 |
| glutamate fermentation-2: mechanism of l-glutamate overproduction in corynebacterium glutamicum. | the nonpathogenic coryneform bacterium, corynebacterium glutamicum, was isolated as an l-glutamate-overproducing microorganism by japanese researchers and is currently utilized in various amino acid fermentation processes. l-glutamate production by c. glutamicum is induced by limitation of biotin and addition of fatty acid ester surfactants and β-lactam antibiotics. these treatments affect the cell surface structures of c. glutamicum. after the discovery of c. glutamicum, many researchers have i ... | 2017 | 27913829 |
| discovery and history of amino acid fermentation. | there has been a strong demand in japan and east asia for l-glutamic acid as a seasoning since monosodium glutamate was found to present umami taste in 1907. the discovery of glutamate fermentation by corynebacterium glutamicum in 1956 enabled abundant and low-cost production of the amino acid, creating a large market. the discovery also prompted researchers to develop fermentative production processes for other l-amino acids, such as lysine. currently, the amino acid fermentation industry is so ... | 2017 | 27909736 |
| transcriptome and multivariable data analysis of corynebacterium glutamicum under different dissolved oxygen conditions in bioreactors. | dissolved oxygen (do) is an important factor in the fermentation process of corynebacterium glutamicum, which is a widely used aerobic microbe in bio-industry. herein, we described rna-seq for c. glutamicum under different do levels (50%, 30% and 0%) in 5 l bioreactors. multivariate data analysis (mvda) models were used to analyze the rna-seq and metabolism data to investigate the global effect of do on the transcriptional distinction of the substance and energy metabolism of c. glutamicum. the ... | 2016 | 27907077 |
| the whcd gene of corynebacterium glutamicum plays roles in cell division and envelope formation. | in this study, we analysed the whcd gene from corynebacteriumglutamicum, which encodes a homologue of whib, a streptomycescoelicolor gene required for the sporulation of aerial hyphae. deletion of the gene (δwhcd) severely affected cell growth in c. glutamicum. the δwhcd strain exhibited a large filamentous, branched and bud-shaped morphology with multiple septa. the transcription levels of the cell division genes involved in z-ring assembly and septal peptidoglycan synthesis, including ftsz, se ... | 2017 | 27902442 |
| expansion of the substrate range of the gentisate 1,2-dioxygenase from corynebacterium glutamicum for the conversion of monohydroxylated benzoates. | the gentisate 1,2-dioxygenases (gdos) from corynebacterium glutamicum and various other organisms oxidatively cleave the aromatic nucleus of gentisate (2,5-dihydroxybenzoate), but are not able to convert salicylate (2-hydroxybenzoate). in contrast, the α-proteobacterium pseudaminobacter salicylatoxidans synthesises an enzyme ('salicylate dioxygenase', sdo) which cleaves gentisate, but also (substituted) salicylate(s). sequence comparisons showed that the sdo belongs to a group of gdos mainly ori ... | 2017 | 27887027 |
| enhanced glucose consumption and organic acid production by engineered corynebacterium glutamicum based on analysis of a pfkb1 deletion mutant. | in the analysis of a carbohydrate metabolite pathway, we found interesting phenotypes in a mutant strain of corynebacterium glutamicum deficient in pfkb1, which encodes fructose-1-phosphate kinase. after being aerobically cultivated with fructose as a carbon source, this mutant consumed glucose and produced organic acid, predominantly l-lactate, at a level more than 2-fold higher than that of the wild-type grown with glucose under conditions of oxygen deprivation. this considerably higher fermen ... | 2017 | 27881414 |
| microbial production of amino acid-related compounds. | corynebacterium glutamicum is the workhorse of the production of proteinogenic amino acids used in food and feed biotechnology. after more than 50 years of safe amino acid production, c. glutamicum has recently also been engineered for the production of amino acid-derived compounds, which find various applications, e.g., as synthons for the chemical industry in several markets including the polymer market. the amino acid-derived compounds such as non-proteinogenic ω-amino acids, α,ω-diamines, an ... | 2017 | 27872963 |
| boosting anaplerotic reactions by pyruvate kinase gene deletion and phosphoenolpyruvate carboxylase desensitization for glutamic acid and lysine production in corynebacterium glutamicum. | in the 1980s, shiio and coworkers demonstrated using random mutagenesis that the following three phenotypes were effective for boosting lysine production by corynebacterium glutamicum: (1) low-activity-level citrate synthase (cs(l)), (2) phosphoenolpyruvate carboxylase (pepc) resistant to feedback inhibition by aspartic acid (pepc(r)), and (3) pyruvate kinase (pyk) deficiency. here, we reevaluated these phenotypes and their interrelationship in lysine production using recombinant dna techniques. ... | 2017 | 27872961 |
| corynebacterium glutamicum for sustainable bioproduction: from metabolic physiology to systems metabolic engineering. | since its discovery 60 years ago, corynebacterium glutamicum has evolved into a workhorse for industrial biotechnology. traditionally well known for its remarkable capacity to produce amino acids, this gram-positive soil bacterium, has become a flexible, efficient production platform for various bulk and fine chemicals, materials, and biofuels. the central turnstile of all these achievements is our excellent understanding of its metabolism and physiology. this knowledge base, together with innov ... | 2016 | 27872959 |
| identification of the camp phosphodiesterase cpda as novel key player in camp-dependent regulation in corynebacterium glutamicum. | the second messenger cyclic amp (camp) plays an important role in the metabolism of corynebacterium glutamicum, as the global transcriptional regulator glxr requires complex formation with camp to become active. whereas a membrane-bound adenylate cyclase, cyab, was shown to be involved in camp synthesis, enzymes catalyzing camp degradation have not been described yet. in this study we identified a class ii camp phosphodiesterase named cpda (cg2761), homologs of which are present in many actinoba ... | 2017 | 27862445 |
| a novel pyruvate kinase and its application in lactic acid production under oxygen deprivation in corynebacterium glutamicum. | pyruvate kinase (pyk) catalyzes the generation of pyruvate and atp in glycolysis and functions as a key switch in the regulation of carbon flux distribution. both the substrates and products of pyk are involved in the tricarboxylic acid cycle, anaplerosis and energy anabolism, which places pyk at a primary metabolic intersection. pyks are highly conserved in most bacteria and lower eukaryotes. corynebacterium glutamicum is an industrial workhorse for the production of various amino acids and org ... | 2016 | 27852252 |
| comparative analysis of the corynebacterium glutamicum transcriptome in response to changes in dissolved oxygen levels. | the dissolved oxygen (do) level of a culture of corynebacterium glutamicum (c. glutamicum) in a bioreactor has a significant impact on the cellular redox potential and the distribution of energy and metabolites. in this study, to gain a deeper understanding of the effects of do on the metabolism of c. glutamicum, we sought to systematically explore the influence of different do concentrations on genetic regulation and metabolism through transcriptomic analysis. the results revealed that after 20 ... | 2017 | 27844170 |
| functional architecture and global properties of the corynebacterium glutamicum regulatory network: novel insights from a dataset with a high genomic coverage. | corynebacterium glutamicum is a gram-positive, anaerobic, rod-shaped soil bacterium able to grow on a diversity of carbon sources like sugars and organic acids. it is a biotechnological relevant organism because of its highly efficient ability to biosynthesize amino acids, such as l-glutamic acid and l-lysine. here, we reconstructed the most complete c. glutamicum regulatory network to date and comprehensively analyzed its global organizational properties, systems-level features and functional a ... | 2017 | 27829123 |
| improved fermentative production of gamma-aminobutyric acid via the putrescine route: systems metabolic engineering for production from glucose, amino sugars, and xylose. | gamma-aminobutyric acid (gaba) is a non-protein amino acid widespread in nature. among the various uses of gaba, its lactam form 2-pyrrolidone can be chemically converted to the biodegradable plastic polyamide-4. in metabolism, gaba can be synthesized either by decarboxylation of l-glutamate or by a pathway that starts with the transamination of putrescine. fermentative production of gaba from glucose by recombinant corynebacterium glutamicum has been described via both routes. putrescine-based ... | 2017 | 27800627 |
| metabolic engineering of corynebacterium glutamicum for shikimate overproduction by growth-arrested cell reaction. | corynebacterium glutamicum with the ability to simultaneously utilize glucose/pentose mixed sugars was metabolically engineered to overproduce shikimate, a valuable hydroaromatic compound used as a starting material for the synthesis of the anti-influenza drug oseltamivir. to achieve this, the shikimate kinase and other potential metabolic activities for the consumption of shikimate and its precursor dehydroshikimate were inactivated. carbon flux toward shikimate synthesis was enhanced by overex ... | 2016 | 27553883 |
| construction of a corynebacterium glutamicum platform strain for the production of stilbenes and (2s)-flavanones. | corynebacterium glutamicum is an important organism in industrial biotechnology for the microbial production of bulk chemicals, in particular amino acids. however, until now activity of a complex catabolic network for the degradation of aromatic compounds averted application of c. glutamicum as production host for aromatic compounds of pharmaceutical or biotechnological interest. in the course of the construction of a suitable c. glutamicum platform strain for plant polyphenol production, four g ... | 2016 | 27288926 |
| mutations in mure, the essential udp-n-acetylmuramoylalanyl-d-glutamate 2,6-diaminopimelate ligase of corynebacterium glutamicum: effect on l-lysine formation and analysis of systemic consequences. | to explore systemic effects of mutations in the udp-n-acetylmuramoylalanyl-d-glutamate 2,6-diaminopimelate ligase (mure) of corynebacterium glutamicum, that leads to extracellular l-lysine accumulation by this bacterium. | 2017 | 27783176 |
| application of crispri in corynebacterium glutamicum for shikimic acid production. | to construct, test and exploit the crispri system for enhancement of shikimic acid production with corynebacterium glutamicum. | 2016 | 27623797 |
| construction of genetic parts from the corynebacterium glutamicum genome with high expression activities. | to construct effective genetic expression parts controlling transcription and translation initiation for synthetic biology and heterologous expression in corynebacterium glutamicum. | 2016 | 27580890 |
| global transcriptomic analysis of the response of corynebacterium glutamicum to ferulic acid. | corynebacterium glutamicum can survive by using ferulic acid as the sole carbon source. in this study, we assessed the response of c. glutamicum to ferulic acid stress by means of a global transcriptional response analysis. the transcriptional data showed that several genes involved in degradation of ferulic acid were affected. moreover, several genes related to the stress response; protein protection or degradation and dna repair; replication, transcription and translation; and the cell envelop ... | 2017 | 27766354 |
| global transcriptomic analysis of the response of corynebacterium glutamicum to vanillin. | lignocellulosic biomass is an abundant and renewable resource for biofuels and bio-based chemicals. vanillin is one of the major phenolic inhibitors in biomass production using lignocellulose. to assess the response of corynebacterium glutamicum to vanillin stress, we performed a global transcriptional response analysis. the transcriptional data showed that the vanillin stress not only affected the genes involved in degradation of vanillin, but also differentially regulated several genes related ... | 2016 | 27760214 |
| glutamine metabolism of corynebacterium glutamicum: role of the glutaminase glsk. | corynebacterium glutamicum is able to metabolize different nitrogen and carbon sources. in standard minimal media, ammonium and urea typically serve as nitrogen source and glucose or sucrose as carbon and energy source; however, amino acids might also play a role as nitrogen, carbon and energy source. in this study, the function of the putative glutaminase glsk was investigated. a glsk deletion strain showed impaired growth with l-glutamine as carbon and energy source, while growth was improved ... | 2016 | 27754855 |
| production of 2-methyl-1-butanol and 3-methyl-1-butanol in engineered corynebacterium glutamicum. | the pentanol isomers 2-methyl-1-butanol and 3-methyl-1-butanol represent commercially interesting alcohols due to their potential application as biofuels. for a sustainable microbial production of these compounds, corynebacterium glutamicum was engineered for producing 2-methyl-1-butanol and 3-methyl-1-butanol via the ehrlich pathway from 2-keto-3-methylvalerate and 2-ketoisocaproate, respectively. in addition to an already available 2-ketoisocaproate producer, a 2-keto-3-methylvalerate accumula ... | 2016 | 27746323 |
| protein secretion in corynebacterium glutamicum. | corynebacterium glutamicum, a gram-positive bacterium, has been widely used for the industrial production of amino acids, such as glutamate and lysine, for decades. due to several characteristics - its ability to secrete properly folded and functional target proteins into culture broth, its low levels of endogenous extracellular proteins and its lack of detectable extracellular hydrolytic enzyme activity - c. glutamicum is also a very favorable host cell for the secretory production of heterolog ... | 2017 | 27737570 |
| increased glucose utilization and cell growth of corynebacterium glutamicum by modifying the glucose-specific phosphotransferase system (pts(glc)) genes. | the phosphoenolpyruvate:glucose phosphotransferase system (pts(glc)) is the major pathway of glucose uptake in corynebacterium glutamicum. this study investigated glucose consumption rate, cell growth, and metabolite changes resulting from modification of pts(glc). the classical l-lysine producer c. glutamicum xq-8 exhibited low glucose consumption, cell growth, and l-lysine production rates, whereas these parameters were significantly increased during cultivating on glucose plus maltose, throug ... | 2016 | 27718589 |
| ciprofloxacin triggered glutamate production by corynebacterium glutamicum. | corynebacterium glutamicum is a well-studied bacterium which naturally overproduces glutamate when induced by an elicitor. glutamate production is accompanied by decreased 2-oxoglutatate dehydrogenase activity. elicitors of glutamate production by c. glutamicum analyzed to molecular detail target the cell envelope. | 2016 | 27717325 |
| attenuating l-lysine production by deletion of ddh and lyse and their effect on l-threonine and l-isoleucine production in corynebacterium glutamicum. | the fermentative production of l-threonine and l-isoleucine with corynebacterium glutamicum is usually accompanied by the by-production of l-lysine, which shares partial biosynthesis pathway with l-threonine and l-isoleucine. since the direct precursor for l-lysine synthesis, diaminopimelate, is a component of peptidoglycan and thus essential for cell wall synthesis, reducing l-lysine by-production could be troublesome. here, a basal strain with eliminated l-lysine production was constructed fro ... | 2016 | 27702487 |
| a toolbox of genetically encoded fret-based biosensors for rapid l-lysine analysis. | background: the fast development of microbial production strains for basic and fine chemicals is increasingly carried out in small scale cultivation systems to allow for higher throughput. such parallelized systems create a need for new rapid online detection systems to quantify the respective target compound. in this regard, biosensors, especially genetically encoded förster resonance energy transfer (fret)-based biosensors, offer tremendous opportunities. as a proof-of-concept, we have created ... | 2016 | 27690044 |
| transcriptomic analysis for elucidating the physiological effects of 5-aminolevulinic acid accumulation on corynebacterium glutamicum. | 5-aminolevulinic acid (ala), the committed intermediate of the heme biosynthetic pathway, attracts close attention among researchers because of its potential applications to cancer treatment and agriculture. overexpression of heterologous hema and heml, which encode glutamyl-trna reductase and glutamate-1-semialdehyde aminotransferase, respectively, in corynebacterium glutamicum produces ala, although whether ala accumulation causes unintended effects on the host is unknown. here we used an inte ... | 2016 | 27664748 |
| metabolic profile of 1,5-diaminopentane producing corynebacterium glutamicum under scale-down conditions: blueprint for robustness to bioreactor inhomogeneities. | performance losses during scale-up are described since decades, but are still one of the major obstacles for industrial bioprocess development. consequently, robustness to inhomogeneous cultivation environments is an important quality of industrial production organisms. especially, corynebacterium glutamicum was proven to have an outstanding resistance against rapid changes of oxygen and substrate availability as occurring in industrial scale bioreactors. this study focuses on the identification ... | 2017 | 27641904 |
| elucidation of the regulatory role of the fructose operon reveals a novel target for enhancing the nadph supply in corynebacterium glutamicum. | the performance of corynebacterium glutamicum cell factories producing compounds which rely heavily on nadph has been reported to depend on the sugar being metabolized. while some aspects of this phenomenon have been elucidated, there are still many unresolved questions as to how sugar metabolism is linked to redox and to the general metabolism. we here provide new insights into the regulation of the metabolism of this important platform organism by systematically characterizing mutants carrying ... | 2016 | 27553884 |
| light-controlled cell factories: employing photocaged isopropyl-β-d-thiogalactopyranoside for light-mediated optimization of lac promoter-based gene expression and (+)-valencene biosynthesis in corynebacterium glutamicum. | precise control of microbial gene expression resulting in a defined, fast, and homogeneous response is of utmost importance for synthetic bio(techno)logical applications. however, even broadly applied biotechnological workhorses, such as corynebacterium glutamicum, for which induction of recombinant gene expression commonly relies on the addition of appropriate inducer molecules, perform moderately in this respect. light offers an alternative to accurately control gene expression, as it allows f ... | 2016 | 27520809 |
| roles of n287 in catalysis and product formation of amylomaltase from corynebacterium glutamicum. | amylomaltase catalyzes intermolecular and intramolecular transglucosylation reactions to form linear and cyclic oligosaccharides, respectively. the aim of this work is to investigate the structure-function relationship of amylomaltase from a mesophilic corynebacterium glutamicum (cgam). site-directed mutagenesis was performed to substitute tyr for asn287 (n287y) to determine its role in controlling amylomaltase activity and product formation. expression of the wild-type (wt) and n287y was achiev ... | 2016 | 27507216 |
| silencing of cryptic prophages in corynebacterium glutamicum. | dna of viral origin represents a ubiquitous element of bacterial genomes. its integration into host regulatory circuits is a pivotal driver of microbial evolution but requires the stringent regulation of phage gene activity. in this study, we describe the nucleoid-associated protein cgps, which represents an essential protein functioning as a xenogeneic silencer in the gram-positive corynebacterium glutamicum cgps is encoded by the cryptic prophage cgp3 of the c. glutamicum strain atcc 13032 and ... | 2016 | 27492287 |
| improvement of the intracellular environment for enhancing l-arginine production of corynebacterium glutamicum by inactivation of h2o2-forming flavin reductases and optimization of atp supply. | l-arginine, a semi essential amino acid, is an important amino acid in food flavoring and pharmaceutical industries. its production by microbial fermentation is gaining more and more attention. in previous work, we obtained a new l-arginine producing corynebacterium crenatum (subspecies of corynebacterium glutamicum) through mutation breeding. in this work, we enhanced l-arginine production through improvement of the intracellular environment. first, two nad(p)h-dependent h2o2-forming flavin red ... | 2016 | 27474351 |
| the obligate respiratory supercomplex from actinobacteria. | actinobacteria are closely linked to human life as industrial producers of bioactive molecules and as human pathogens. respiratory cytochrome bcc complex and cytochrome aa3 oxidase are key components of their aerobic energy metabolism. they form a supercomplex in the actinobacterial species corynebacterium glutamicum. with comprehensive bioinformatics and phylogenetic analysis we show that genes for cyt bcc-aa3 supercomplex are characteristic for actinobacteria (actinobacteria and acidimicrobiia ... | 2016 | 27472998 |
| erratum to: the actinobacterium corynebacterium glutamicum, an industrial workhorse. | this erratum is being published to correct the 3rd author's name of above manuscript by lee et al. that was published in journal of microbiology and biotechnology (2016, 26: 807-822). the 3rd author name(eungsoo kim) should appear as 'eung-soo kim'. | 2016 | 27452344 |
| overexpression of mycothiol disulfide reductase enhances corynebacterium glutamicum robustness by modulating cellular redox homeostasis and antioxidant proteins under oxidative stress. | mycothiol (msh) is the dominant low-molecular-weight thiol (lmwt) unique to high-(g+c)-content gram-positive actinobacteria, such as corynebacterium glutamicum, and is oxidised into its disulfide form mycothiol disulfide (mssm) under oxidative conditions. mycothiol disulfide reductase (mtr), an nadph-dependent enzyme, reduces mssm to msh, thus maintaining intracellular redox homeostasis. in this study, a recombinant plasmid was constructed to overexpress mtr in c. glutamicum using the expression ... | 2016 | 27383057 |
| a method for simultaneous gene overexpression and inactivation in the corynebacterium glutamicum genome. | the gene integration method is an important tool to stably express desirable genes in bacteria. to avoid heavy workload and cost, we constructed a rapid and efficient method for genome modification. this method depended on a mobilizable plasmid, which contains a p tac promoter, an introduced multiple cloning site (imcs), and rrnbt1t2 terminator. briefly, the mobilizable plasmid pk18-mbpmt with the p tac-imcs-rrnbt1t2 cartridge derived from pk18mobsacb was prepared to directly integrate hetero-/h ... | 2016 | 27377799 |
| biotypes analysis of corynebacterium glutamicum growing in dicarboxylic acids demonstrates the existence of industrially-relevant intra-species variations. | production enhancement of industrial microbial products or strains has been traditionally tackled by mutagenesis with chemical methods, irradiation or genetic manipulation. however, the final yield increase must go hand in hand with the resistance increasing against the usual inherent toxicity of the final products. few studies have been carried out on resistance improvement and even fewer on the initial selection of naturally-generated biotypes, which could decrease the artificial mutagenesis. ... | 2016 | 27371347 |
| crystal structure of amylomaltase from corynebacterium glutamicum. | amylomaltase is an essential enzyme in maltose utilization and maltodextrin metabolism, and it has been industrially used for the production of cyclodextrin and modification of starch. we determined the crystal structure of amylomaltase from corynebacterium glutamicum (cgam) at a resolution of 1.7 å. although cgam forms a dimer without nacl, it exists as a monomer in physiological concentration of nacl. cgam is composed of n- and c-terminal domains, which can be further divided into two and four ... | 2016 | 27366969 |
| the small 6c rna of corynebacterium glutamicum is involved in the sos response. | the 6c rna family is a class of small rnas highly conserved in actinobacteria, including the genera mycobacterium, streptomyces and corynebacterium whose physiological function has not yet been elucidated. we found that strong transcription of the cgb_03605 gene, which encodes 6c rna in c. glutamicum, was driven by the siga- and sigb-dependent promoter pcgb_03605. 6c rna was detected at high level during exponential growth phase (180 to 240 molcules per cell) which even increased at the entry of ... | 2016 | 27362471 |
| a novel acee mutation leading to a better growth profile and a higher l-serine production in a high-yield l-serine-producing corynebacterium glutamicum strain. | a comparative genomic analysis was performed to study the genetic variations between the l-serine-producing strain corynebacterium glutamicum syps-062 and the mutant strain syps-062-33a, which was derived from syps-062 by random mutagenesis with enhanced l-serine production. some variant genes between the two strains were reversely mutated or deleted in the genome of syps-062-33a to verify the influences of the gene mutations introduced by random mutagenesis. it was found that a his-594 → tyr mu ... | 2016 | 27344574 |
| systems pathway engineering of corynebacterium crenatum for improved l-arginine production. | l-arginine is an important amino acid in food and pharmaceutical industries. until now, the main production method of l-arginine in china is the highly polluting keratin acid hydrolysis. the industrial level l-arginine production by microbial fermentation has become an important task. in previous work, we obtained a new l-arginine producing corynebacterium crenatum (subspecies of corynebacterium glutamicum) through screening and mutation breeding. in this work, we performed systems pathway engin ... | 2016 | 27338253 |
| graded response of the multifunctional 2-cysteine peroxiredoxin, cgprx, to increasing levels of hydrogen peroxide in corynebacterium glutamicum. | eukaryotic typical 2-cysteine (cys) peroxiredoxins (prxs) are multifunctional proteins subjected to complex regulation and play important roles in oxidative stress resistance, hydrogen peroxide (h2o2) signaling modulation, aging, and cancer, but the information on the biochemical functions and regulation mechanisms of prokaryotic atypical 2-cys prxs is largely lacking. | 2017 | 27324811 |
| formation of xylitol and xylitol-5-phosphate and its impact on growth of d-xylose-utilizing corynebacterium glutamicum strains. | wild-type corynebacterium glutamicum has no endogenous metabolic activity for utilizing the lignocellulosic pentose d-xylose for cell growth. therefore, two different engineering approaches have been pursued resulting in platform strains harbouring a functional version of either the isomerase (iso) or the weimberg (wmb) pathway for d-xylose assimilation. in a previous study we found for c. glutamicum wmb by-product formation of xylitol during growth on d-xylose and speculated that the observed l ... | 2016 | 27297548 |
| corynebacterium glutamicum mtcc 2745 immobilized on granular activated carbon/mnfe2o4 composite: a novel biosorbent for removal of as(iii) and as(v) ions. | the optimization of biosorption/bioaccumulation process of both as(iii) and as(v) has been investigated by using the biosorbent; biofilm of corynebacterium glutamicum mtcc 2745 supported on granular activated carbon/mnfe2o4 composite (mgac). the presence of functional groups on the cell wall surface of the biomass that may interact with the metal ions was proved by ft-ir. to determine the most appropriate correlation for the equilibrium curves employing the procedure of the non-linear regression ... | 2016 | 27289352 |
| transcription of sialic acid catabolism genes in corynebacterium glutamicum is subject to catabolite repression and control by the transcriptional repressor nanr. | corynebacterium glutamicum metabolizes sialic acid (neu5ac) to fructose-6-phosphate (fructose-6p) via the consecutive activity of the sialic acid importer siaefgi, n-acetylneuraminic acid lyase (nana), n-acetylmannosamine kinase (nank), n-acetylmannosamine-6p epimerase (nane), n-acetylglucosamine-6p deacetylase (naga), and glucosamine-6p deaminase (nagb). within the cluster of the three operons nagab, nanake, and siaefgi for neu5ac utilization a fourth operon is present, which comprises cg2936, ... | 2016 | 27274030 |
| use of in vitro transcription system for analysis of corynebacterium glutamicum promoters recognized by two sigma factors. | promoter activities in corynebacterium glutamicum strains with deletions of genes encoding sigma factors of rna polymerase suggested that transcription from some promoters is controlled by two sigma factors. to prove that different sigma factors are involved in the recognition of selected corynebacterium glutamicum promoters, in vitro transcription system was applied. it was found that a typical housekeeping promoter pper interacts with the alternative sigma factor σ(b) in addition to the primar ... | 2016 | 27270733 |
| metabolic engineering of corynebacterium glutamicum for methionine production by removing feedback inhibition and increasing nadph level. | relieving the feedback inhibition of key enzymes in a metabolic pathway is frequently the first step of producer-strain construction by genetic engineering. however, the strict feedback regulation exercised by microorganisms in methionine biosynthesis often makes it difficult to produce methionine at a high level. in this study, corynebacterium glutamicum atcc 13032 was metabolically engineered for methionine production. first, the metd gene encoding the methionine uptake system was deleted to a ... | 2016 | 27255137 |
| mycothiol protects corynebacterium glutamicum against acid stress via maintaining intracellular ph homeostasis, scavenging ros, and s-mycothiolating mete. | mycothiol (msh) plays a major role in protecting cells against oxidative stress and detoxification from a broad range of exogenous toxic agents. in the present study, we reveal that intracellular msh contributes significantly to the adaptation to acidic conditions in the model organism corynebacterium glutamicum. we present evidence that msh confers c. glutamicum with the ability to adapt to acidic conditions by maintaining phi homeostasis, scavenging reactive oxygen species (ros), and protectin ... | 2016 | 27250661 |
| structural characterization of heme environmental mutants of cghmut that shuttles heme molecules to heme transporters. | corynebacteria contain a heme uptake system encoded in hmutuv genes, in which hmut protein acts as a heme binding protein to transport heme to the cognate transporter hmuuv. the crystal structure of hmut from corynebacterium glutamicum (cghmut) reveals that heme is accommodated in the central cleft with his141 and tyr240 as the axial ligands and that tyr240 forms a hydrogen bond with arg242. in this work, the crystal structures of h141a, y240a, and r242a mutants were determined to understand the ... | 2016 | 27240352 |
| cathodes enhance corynebacterium glutamicum growth with nitrate and promote acetate and formate production. | the industrially important corynebacterium glutamicum can only incompletely reduce nitrate into nitrite which then accumulates and inhibits growth. herein we report that cathodes can resolve this problem and enhance glucose fermentation and growth by promoting nitrite reduction. cell growth was inhibited at relatively high potentials but was significant when potentials were more reductive (-1.20v with anthraquinone-2-sulfonate as redox mediator or -1.25v vs. ag/agcl). under these conditions, glu ... | 2016 | 27235972 |
| overexpression of ppc and lysc to improve the production of 4-hydroxyisoleucine and its precursor l-isoleucine in recombinant corynebacterium glutamicum ssp. lactofermentum. | 4-hydroxyisoleucine (4-hil) exhibits unique insulinotropic and insulin-sensitizing activities and is an attractive candidate for the treatment of type ii and type i diabetes. in our previous study, l-isoleucine dioxygenase gene (ido) was cloned and overexpressed in an l-isoleucine-producing strain, corynebacterium glutamicum ssp. lactofermentum sn01, and 4-hil was produced from the endogenous l-isoleucine (ile). in this study, ppc and lysc were co-expressed with ido to increase the supply of ile ... | 2016 | 27178798 |