| influence of nanomechanical stress induced by zno nanoparticles of different shapes on the viability of cells. | there is growing interest in nanostructures interacting with living organisms. however, there are still no general rules for the design of biocompatible nanodevices. here, we present a step towards understanding the interactions between nanostructures and living cells. we study the influence of nanomechanical stress induced by zinc oxide (zno) nanostructures of different shapes on the viability of both prokaryotic (gram-negative bacteria: escherichia coli and enterobacter aerogenes, and gram-pos ... | 2016 | 27074722 |
| dihydroxyacetone production in an engineered escherichia coli through expression of corynebacterium glutamicum dihydroxyacetone phosphate dephosphorylase. | dihydroxyacetone (dha) has several industrial applications such as a tanning agent in tanning lotions in the cosmetic industry; its production via microbial fermentation would present a more sustainable option for the future. here we genetically engineered escherichia coli (e. coli) for dha production from glucose. deletion of e. coli triose phosphate isomerase (tpia) gene was carried out to accumulate dihydroxyacetone phosphate (dhap), for use as the main intermediate or precursor for dha produ ... | 2016 | 26992791 |
| production of succinic acid by metabolically engineered microorganisms. | succinic acid (sa) has been recognized as one of the most important bio-based building block chemicals due to its numerous potential applications. for the economical bio-based production of sa, extensive research works have been performed on developing microbial strains by metabolic engineering as well as fermentation and downstream processes. here we review metabolic engineering strategies applied for bio-based production of sa using representative microorganisms, including saccharomyces cerevi ... | 2016 | 26990278 |
| pathway construction and metabolic engineering for fermentative production of ectoine in escherichia coli. | ectoine is a protective agent and stabilizer whose synthesis pathway exclusively exists in select moderate halophiles. a novel established process called "bacterial milking" efficiently synthesized ectoine in moderate halophiles, however, this method places high demands on equipment and is cost prohibitive. in this study, we constructed an ectoine producing strain by introducing the ectoine synthesis pathway into escherichia coli and improved its production capacity. firstly, the ectabc gene clu ... | 2016 | 26969253 |
| a new strategy for production of 5-aminolevulinic acid in recombinant corynebacterium glutamicum with high yield. | 5-aminolevulinic acid (ala), a nonprotein amino acid involved in tetrapyrrole synthesis, has been widely applied in agriculture, medicine, and food production. many engineered metabolic pathways have been constructed; however, the production yields are still low. in this study, several 5-aminolevulinic acid synthases (alass) from different sources were evaluated and compared with respect to their ala production capacities in an engineered corynebacterium glutamicum cgs1 strain that can accumulat ... | 2016 | 26921424 |
| microfluidic screening of electric fields for electroporation. | electroporation is commonly used to deliver molecules such as drugs, proteins, and/or dna into cells, but the mechanism remains poorly understood. in this work a rapid microfluidic assay was developed to determine the critical electric field threshold required for inducing bacterial electroporation. the microfluidic device was designed to have a bilaterally converging channel to amplify the electric field to magnitudes sufficient to induce electroporation. the bacterial cells are introduced into ... | 2016 | 26893024 |
| strategies used for genetically modifying bacterial genome: site-directed mutagenesis, gene inactivation, and gene over-expression. | with the availability of the whole genome sequence of escherichia coli or corynebacterium glutamicum, strategies for directed dna manipulation have developed rapidly. dna manipulation plays an important role in understanding the function of genes and in constructing novel engineering bacteria according to requirement. dna manipulation involves modifying the autologous genes and expressing the heterogenous genes. two alternative approaches, using electroporation linear dna or recombinant suicide ... | 2016 | 26834010 |
| web application for genetic modification flux with database to estimate metabolic fluxes of genetic mutants. | computational analysis of metabolic fluxes is essential in understanding the structure and function of a metabolic network and in rationally designing genetically modified mutants for an engineering purpose. we had presented the genetic modification flux (gmf) that predicts the flux distribution of a broad range of genetically modified mutants. to enhance the feasibility and usability of gmf, we have developed a web application with a metabolic network database to predict a flux distribution of ... | 2016 | 26777238 |
| in vitro functional characterization of the na+/h+ antiporters in corynebacterium glutamicum. | corynebacterium glutamicum, typically used as industrial workhorse for amino acid production, is a moderately salt-alkali-tolerant microorganism with optimal growth at ph 7-9. however, little is known about the mechanisms of salt-alkali tolerance in c. glutamicum. here, the catalytic capacity of three putative na(+)/h(+) antiporters from c. glutamicum (designated as cg-mrp1, cg-mrp2 and cg-nhap) were characterized in an antiporter-deficient escherichia coli knabc strain. only cg-mrp1 was able to ... | 2016 | 26667218 |
| enhanced production of 3-hydroxypropionic acid from glucose via malonyl-coa pathway by engineered escherichia coli. | in this study, production of 3-hp via malonyl-coa was investigated by using metabolically engineered escherichia coli carrying heterogeneous acetyl-coa carboxylase (acc) from corynebacterium glutamicum and codon-optimized malonyl-coa reductase (mcr) from chloroflexus aurantiacus. three engineered e. coli strains with different host-vector systems were constructed and investigated. the results indicated that the combination of e. coli bl21(de3) and pet28a was the most efficient host-vector system ... | 2016 | 26606325 |
| fudc, a protein primarily responsible for furfural detoxification in corynebacterium glutamicum. | lignocellulosic hydrolysates contain compounds that inhibit microbial growth and fermentation, thereby decreasing the productivity of biofuel and biochemical production. in particular, the heterocyclic aldehyde furfural is one of the most toxic compounds found in these hydrolysates. we previously demonstrated that corynebacterium glutamicum converts furfural into the less toxic compounds furfuryl alcohol and 2-furoic acid. to date, however, the genes involved in these oxidation and reduction rea ... | 2016 | 26541332 |
| the impact of the c-terminal domain on the gating properties of msccg from corynebacterium glutamicum. | the mechanosensitive (ms) channel msccg from the soil bacterium corynebacterium glutamicum functions as a major glutamate exporter. msccg belongs to a subfamily of the bacterial mscs-like channels, which play an important role in osmoregulation. to understand the structural and functional features of msccg, we investigated the role of the carboxyl-terminal domain, whose relevance for the channel gating has been unknown. the chimeric channel mscs-(c-msccg), which is a fusion protein between the c ... | 2016 | 26494188 |
| production of protocatechuic acid by corynebacterium glutamicum expressing chorismate-pyruvate lyase from escherichia coli. | protocatechuic acid (3,4-dihydroxybenzoic acid; pca) serves as a building block for polymers and pharmaceuticals. in this study, the biosynthetic pathway for pca from glucose was engineered in corynebacterium glutamicum. the pathway to pca-employed elements of the chorismate pathway by using chorismate-pyruvate lyase (cpl) and 4-hydroxybenzoate hydroxylase (4-hba hydroxylase). as c. glutamicum has the potential to synthesize the aromatic amino acid intermediate chorismate and possesses 4-hba hyd ... | 2016 | 26392137 |
| metabolic engineering of the mixed-acid fermentation pathway of escherichia coli for anaerobic production of glutamate and itaconate. | itaconic acid, an unsaturated c5-dicarboxylic acid, is a biobased building block for the polymer industry. the purpose of this study was to establish proof of principle for an anaerobic fermentation process for the production of itaconic acid by modification of the mixed acid fermentation pathway of e. coli. e. coli bw25113 (de3) and the phosphate acetyltransferase (pta) and lactate dehydrogenase (ldha) deficient strain e. coli bw25113 (de3) δpta-δldha were used to study anaerobic itaconate prod ... | 2015 | 26384341 |
| engineering of corynebacterium glutamicum for growth and succinate production from levoglucosan, a pyrolytic sugar substrate. | thermochemical processing provides continuous production of bio-oils from lignocellulosic biomass. levoglucosan, a pyrolytic sugar substrate c6h10o5 in a bio-oil, has been used for ethanol production using engineered escherichia coli. here we provide the first example for succinate production from levoglucosan with corynebacterium glutamicum, a well-known industrial amino acid producer. heterologous expression of a gene encoding a sugar kinase from lipomyces starkeyi, gibberella zeae or pseudomo ... | 2015 | 26363018 |
| metabolic engineering of escherichia coli for the production of 3-aminopropionic acid. | a novel metabolic pathway was designed for the production of 3-aminopropionic acid (3-ap), an important platform chemical for manufacturing acrylamide and acrylonitrile. using a fumaric acid producing escherichia coli strain as a host, the corynebacterium glutamicum pand gene (encoding l-aspartate-α-decarboxylase) was overexpressed and the native promoter of the aspa gene was replaced with the strong trc promoter, which allowed aspartic acid production through the aspartase-catalyzed reaction. a ... | 2015 | 26057003 |
| construction of synthetic promoter-based expression cassettes for the production of cadaverine in recombinant corynebacterium glutamicum. | corynebacterium glutamicum is an important microorganism in the biochemical industry for the production of various platform chemicals. however, despite its importance, a limited number of studies have been conducted on how to constitute gene expression cassettes in engineered c. glutamicum to obtain desired amounts of the target products. therefore, in this study, six expression cassettes for the expression of the second lysine decarboxylase of escherichia coli, ldcc, were constructed using six ... | 2015 | 26047931 |
| fermentative production of the diamine putrescine: system metabolic engineering of corynebacterium glutamicum. | corynebacterium glutamicum shows great potential for the production of the glutamate-derived diamine putrescine, a monomeric compound of polyamides. a genome-scale stoichiometric model of a c. glutamicum strain with reduced ornithine transcarbamoylase activity, derepressed arginine biosynthesis, and an anabolic plasmid-addiction system for heterologous expression of e. coli ornithine decarboxylase gene spec was investigated by flux balance analysis with respect to its putrescine production poten ... | 2015 | 25919117 |
| development of an orthogonal fatty acid biosynthesis system in e. coli for oleochemical production. | here we report recombinant expression and activity of several type i fatty acid synthases that can function in parallel with the native escherichia coli fatty acid synthase. corynebacterium glutamicum fas1a was the most active in e. coli and this fatty acid synthase was leveraged to produce oleochemicals including fatty alcohols and methyl ketones. coexpression of fas1a with the acp/coa-reductase maqu2220 from marinobacter aquaeolei shifted the chain length distribution of fatty alcohols produce ... | 2015 | 25887638 |
| enhanced production of gamma-aminobutyrate (gaba) in recombinant corynebacterium glutamicum by expressing glutamate decarboxylase active in expanded ph range. | gamma-aminobutylate (gaba) is an important chemical in pharmacetucal field and chemical industry. gaba has mostly been produced in lactic acid bacteria by adding l-glutamate to the culture medium since l-glutamate can be converted into gaba by inherent l-glutamate decarboxylase. recently, gaba has gained much attention for the application as a major building block for the synthesis of 2-pyrrolidone and biodegradable polyamide nylon 4, which opens its application area in the industrial biotechnol ... | 2015 | 25886194 |
| regulation of expression of soda and msra genes of corynebacterium glutamicum in response to oxidative and radiative stress. | promoters of genes encoding superoxide dismutase (soda) and peptide methionine sulfoxide reductase (msra) from cory-nebacterium glutamicum were cloned and sequenced. promoter region analysis of soda-msra was unable to identify putative sites of fixed eventual regulators except for possible sites of fixed oxyr and integra-tion host factor. a study of the regulation of these genes was performed using the lacz gene of escherichia coli as a reporter placed under the control of sequences downstream o ... | 2015 | 25867357 |
| characterization of a flavin-containing monooxygenase from corynebacterium glutamicum and its application to production of indigo and indirubin. | to examine the role of a gene encoding flavin-containing monooxygenase (cfmo) from corynebacterium glutamicum atcc13032 when cloned and expressed in escherichia coli for the production of indigo pigments. | 2015 | 25851950 |
| diaminopimelic acid amidation in corynebacteriales: new insights into the role of ltsa in peptidoglycan modification. | a gene named ltsa was earlier identified in rhodococcus and corynebacterium species while screening for mutations leading to increased cell susceptibility to lysozyme. the encoded protein belonged to a huge family of glutamine amidotransferases whose members catalyze amide nitrogen transfer from glutamine to various specific acceptor substrates. we here describe detailed physiological and biochemical investigations demonstrating the specific role of ltsa protein from corynebacterium glutamicum ( ... | 2015 | 25847251 |
| distinct paths for basic amino acid export in escherichia coli: ybje (lyso) mediates export of l-lysine. | in escherichia coli, argo encodes an exporter for l-arginine (arg) and its toxic analogue canavanine (can), and its transcriptional activation and repression, by arg and l-lysine (lys), respectively, are mediated by the regulator argp. accordingly argo and argp mutants are can supersensitive (can(ss)). we report the identification of ybje as a gene encoding a predicted inner membrane protein that mediates export of lys, and our results confirm the previous identification with a different approac ... | 2015 | 25845847 |
| identification of essential tryptophan in amylomaltase from corynebacterium glutamicum. | this work aims to identify essential tryptophan residue(s) of amylomaltase from corynebacterium glutamicum (cgam) through chemical modification and site-directed mutagenesis techniques. the recombinant enzyme expressed by escherichia coli was purified and treated with n-bromosuccinimide (nbs), a modifying agent for tryptophan. a significant decrease in enzyme activity was observed indicating that tryptophan is important for catalysis. inactivation kinetics with nbs resulted in pseudo first-order ... | 2015 | 25748841 |
| expression of recombinant protein using corynebacterium glutamicum: progress, challenges and applications. | corynebacterium glutamicum (c. glutamicum) is a highly promising alternative prokaryotic host for recombinant protein expression, as it possesses several significant advantages over escherichia coli (e. coli), the currently leading bacterial protein expression system. during the past decades, several experimental techniques and vector components for genetic manipulation of c. glutamicum have been developed and validated, including strong promoters for tightly regulating target gene expression, v ... | 2016 | 25714007 |
| advanced biotechnology: metabolically engineered cells for the bio-based production of chemicals and fuels, materials, and health-care products. | corynebacterium glutamicum, escherichia coli, and saccharomyces cerevisiae in particular, have become established as important industrial workhorses in biotechnology. recent years have seen tremendous progress in their advance into tailor-made producers, driven by the upcoming demand for sustainable processes and renewable raw materials. here, the diversity and complexity of nature is simultaneously a challenge and a benefit. harnessing biodiversity in the right manner through synergistic progre ... | 2015 | 25684732 |
| methanol-based cadaverine production by genetically engineered bacillus methanolicus strains. | methanol is regarded as an attractive substrate for biotechnological production of value-added bulk products, such as amino acids and polyamines. in the present study, the methylotrophic and thermophilic bacterium bacillus methanolicus was engineered into a microbial cell factory for the production of the platform chemical 1,5-diaminopentane (cadaverine) from methanol. this was achieved by the heterologous expression of the escherichia coli genes cada and ldcc encoding two different lysine decar ... | 2015 | 25644214 |
| transcriptional regulation of the vanillate utilization genes (vanabk operon) of corynebacterium glutamicum by vanr, a padr-like repressor. | corynebacterium glutamicum is able to utilize vanillate, the product of lignin degradation, as the sole carbon source. the vanillate utilization components are encoded by the vanabk operon. the vana and vanb genes encode the subunits of vanillate o-demethylase, converting vanillate to protocatechuate, while vank is the specific vanillate transporter. the vanabk operon is regulated by a padr-type repressor, vanr. heterologous gene expression and variations of the vanr open reading frame revealed ... | 2015 | 25535273 |
| functional characterization of corynebacterium glutamicum mycothiol s-conjugate amidase. | the present study focuses on the genetic and biochemical characterization of mycothiol s-conjugate amidase (mca) of corynebacterium glutamicum. recombinant c. glutamicum mca was heterologously expressed in escherichia coli and purified to apparent homogeneity. the molecular weight of native mca protein determined by gel filtration chromatography was 35 kda, indicating that mca exists as monomers in the purification condition. mca showed amidase activity with mycothiol s-conjugate of monobromobim ... | 2014 | 25514023 |
| engineering microorganisms based on molecular evolutionary analysis: a succinate production case study. | evolution has resulted in thousands of species possessing similar metabolic enzymes with identical functions that are, however, regulated by different mechanisms. it is thus difficult to select optimal gene to engineer novel or manipulated metabolic pathways. here, we tested the ability of molecular evolutionary analysis to identify appropriate genes from various species. we calculated the fraction of synonymous substitution and the effective number of codons (enc) for nine genes stemming from g ... | 2014 | 25469170 |
| discovery of a bacterial 5-methylcytosine deaminase. | 5-methylcytosine is found in all domains of life, but the bacterial cytosine deaminase from escherichia coli (coda) will not accept 5-methylcytosine as a substrate. since significant amounts of 5-methylcytosine are produced in both prokaryotes and eukaryotes, this compound must eventually be catabolized and the fragments recycled by enzymes that have yet to be identified. we therefore initiated a comprehensive phylogenetic screen for enzymes that may be capable of deaminating 5-methylcytosine to ... | 2014 | 25384249 |
| generation of minicells from an endotoxin-free gram-positive strain corynebacterium glutamicum. | drug delivery systems (ddss) incorporating bacterial minicells have been evaluated as a very powerful tool in view of biocompatibility. however, limited studies have been carried out on these systems, mainly using minicells from salmonella sp. and escherichia coli. thus, we generated a new minicell-producing strain from an endotoxin-free corynebacterium glutamicum by the inactivation of genes related to cell division. the two knockout strains, δpara and δncgl1366, showed distinct abilities to pr ... | 2015 | 25341464 |
| increasing available nadh supply during succinic acid production by corynebacterium glutamicum. | a critical factor in the biotechnological production of succinic acid with corynebacterium glutamicum is the sufficient supply of nadh. it is conceivable that cofactor availability and the proportion of cofactor in the active form may play an important role in dictating the succinic acid yield. pntab genes from escherichia coli can directly catalyze the reversible hydride transfer and adjust the dynamic balance between nadp(h) and nad(h). hence, we studied the physiological effect of coenzyme sy ... | 2015 | 25311136 |
| biosynthesis of rare ketoses through constructing a recombination pathway in an engineered corynebacterium glutamicum. | rare sugars have various known biological functions and potential for applications in pharmaceutical, cosmetics, and food industries. here we designed and constructed a recombination pathway in corynebacterium glutamicum, in which dihydroxyacetone phosphate (dhap), an intermediate of the glycolytic pathway, and a variety of aldehydes were condensed to synthesize rare ketoses sequentially by rhamnulose-1-phosphate aldolase (rhad) and fructose-1-phosphatase (yqab) obtained from escherichia coli. a ... | 2015 | 25060350 |
| metabolic engineering of escherichia coli for the production of riboflavin. | riboflavin (vitamin b2), the precursor of the flavin cofactors flavin mononucleotide (fmn) and flavin adenine dinucleotide (fad), is used commercially as an animal feed supplement and food colorant. e. coli is a robust host for various genetic manipulations and has been employed for efficient production of biofuels, polymers, amino acids, and bulk chemicals. thus, the aim of this study was to understand the metabolic capacity of e. coli for the riboflavin production by modification of central me ... | 2014 | 25027702 |
| enhanced acetic acid and succinic acid production under microaerobic conditions by corynebacterium glutamicum harboring escherichia coli transhydrogenase gene pntab. | some microorganisms, such as escherichia coli, harbor transhydrogenases that catalyze the interconversion between nadph and nadh. however, such transhydrogenase genes have not been found in the genome of a glutamic acid-producing bacterium corynebacterium glutamicum. in this study, the e. coli transhydrogenase genes udha and pntab were introduced into the c. glutamicum wild-type strain atcc 13032, and the metabolic characteristics of the recombinant strains under aerobic and microaerobic conditi ... | 2014 | 25008167 |
| disruption of pkng enhances production of gamma-aminobutyric acid by corynebacterium glutamicum expressing glutamate decarboxylase. | gamma-aminobutyric acid (gaba), a building block of the biodegradable plastic polyamide 4, is synthesized from glucose by corynebacterium glutamicum that expresses escherichia coli glutamate decarboxylase (gad) b encoded by gadb. this strain was engineered to produce gaba more efficiently from biomass-derived sugars. to enhance gaba production further by increasing the intracellular concentration of its precursor glutamate, we focused on engineering pkng (encoding serine/threonine protein kinase ... | 2014 | 24949255 |
| [progress in biosythesis of diaminopentane]. | air pollution and global warming are increasingly deteriorating. large amounts of polyamides derived from fossil fuel sources are consumed around the world. cadaverine is an important building monomer block of bio-based polyamides, thus biotechnological processes for these polymers possess enormous ecological and economical potential. currently, the engineered strains for biological production of cadaverine are corynebacterium glutamicum and escherichia coli. we review here the latest research p ... | 2014 | 24941739 |
| microbial production of amino acids and derived chemicals: synthetic biology approaches to strain development. | amino acids are produced at the multi-million-ton-scale with fermentative production of l-glutamate and l-lysine alone being estimated to amount to more than five million tons in the year 2013. metabolic engineering constantly improves productivities of amino acid producing strains, mainly corynebacterium glutamicum and escherichia coli strains. classical mutagenesis and screening have been accelerated by combination with intracellular metabolite sensing. synthetic biology approaches have allowe ... | 2014 | 24922334 |
| production of the sesquiterpene (+)-valencene by metabolically engineered corynebacterium glutamicum. | the sesquiterpene (+)-valencene is an aroma compound of citrus fruits and is used to flavor foods and drinks. biosynthesis of (+)-valencene starts from farnesyl pyrophosphate, an intermediate of carotenoid biosynthesis. corynebacterium glutamicum, the workhorse of the million-ton scale amino acid industry, is naturally pigmented as it synthesizes the rare fifty carbon atoms (c50) containing carotenoid decaprenoxanthin. since the carotenoid pathway of this gram-positive bacterium has previously b ... | 2014 | 24910970 |
| application of metabolic engineering for the biotechnological production of l-valine. | the branched chain amino acid l-valine is an essential nutrient for higher organisms, such as animals and humans. besides the pharmaceutical application in parenteral nutrition and as synthon for the chemical synthesis of e.g. herbicides or anti-viral drugs, l-valine is now emerging into the feed market, and significant increase of sales and world production is expected. in accordance, well-known microbial production bacteria, such as escherichia coli and corynebacterium glutamicum strains, have ... | 2014 | 24816722 |
| synthesis of β-alanine from l-aspartate using l-aspartate-α-decarboxylase from corynebacterium glutamicum. | β-alanine is mainly produced by chemical methods in current industrial processes. here, pand from corynebacterium glutamicum encoding l-aspartate-α-decarboxylase (adc) was cloned and expressed in escherichia coli bl21(de3). adc c.g catalyzes the α-decarboxylation of l-aspartate to β-alanine. the purified adc c.g was optimal at 55 °c and ph 6 with excellent stability at 16-37 °c and ph 4-7. a ph-stat directed, fed-batch feeding strategy was developed for enzymatic synthesis of β-alanine to keep t ... | 2014 | 24737081 |
| synthetic biology platform of corynebrick vectors for gene expression in corynebacterium glutamicum and its application to xylose utilization. | currently, the majority of tools in synthetic biology have been designed and constructed for model organisms such as escherichia coli and saccharomyces cerevisiae. in order to broaden the spectrum of organisms accessible to such tools, we established a synthetic biological platform, called corynebrick, for gene expression in corynebacterium glutamicum as a set of e. coli-c. glutamicum shuttle vectors whose elements are interchangeable with bglbrick standard parts. c. glutamicum is an established ... | 2014 | 24706215 |
| [effect of overexpressing isocitrate lyase on succinate production in ldh(-1) corynebacterium glutamicum]. | corynebacterium glutamicum sa001 is a mutant with lactate dehydrogenase (ldha) deletion. in order to increase metabolic flux from isocitrate to succinate, and to improve the production of succinate under anaerobic conditions,we transducted the gene acea coding isocitrate lyase (icl) from escherichia coli k12 into corynebacterium glutamicum sa001 (sa001/pxmj19-acea). after 12 h aerobic induction by adding 0.8 mmol/l of iptg, the recombinant strain was transferred to anaerobic fermentation for 16 ... | 2013 | 24701837 |
| engineering of corynebacterium glutamicum for growth and l-lysine and lycopene production from n-acetyl-glucosamine. | sustainable supply of feedstock has become a key issue in process development in microbial biotechnology. the workhorse of industrial amino acid production corynebacterium glutamicum has been engineered towards utilization of alternative carbon sources. utilization of the chitin-derived aminosugar n-acetyl-glucosamine (glcnac) for both cultivation and production with c. glutamicum has hitherto not been investigated. albeit this organism harbors the enzymes n-acetylglucosamine-6-phosphatedeacetyl ... | 2014 | 24668244 |
| improving the secretion of cadaverine in corynebacterium glutamicum by cadaverine-lysine antiporter. | cadaverine (1,5-pentanediamine, diaminopentane), the desired raw material of bio-polyamides, is an important industrial chemical with a wide range of applications. biosynthesis of cadaverine in corynebacterium glutamicum has been a competitive way in place of petroleum-based chemical synthesis method. to date, the cadaverine exporter has not been found in c. glutamicum. in order to improve cadaverine secretion, the cadaverine-lysine antiporter cadb from escherichia coli was studied in c. glutami ... | 2014 | 24510022 |
| synthetic promoter libraries for corynebacterium glutamicum. | the ability to modulate gene expression is an important genetic tool in systems biology and biotechnology. here, we demonstrate that a previously published easy and fast pcr-based method for modulating gene expression in lactic acid bacteria is also applicable to corynebacterium glutamicum. we constructed constitutive promoter libraries based on various combinations of a previously reported c. glutamicum -10 consensus sequence (gngnta(c/t)aatgg) and the escherichia coli -35 consensus, either wit ... | 2014 | 24458563 |
| coupling bioorthogonal chemistries with artificial metabolism: intracellular biosynthesis of azidohomoalanine and its incorporation into recombinant proteins. | in this paper, we present a novel, "single experiment" methodology based on genetic engineering of metabolic pathways for direct intracellular production of non-canonical amino acids from simple precursors, coupled with expanded genetic code. in particular, we engineered the intracellular biosynthesis of l-azidohomoalanine from o-acetyl-l-homoserine and nan3, and achieved its direct incorporation into recombinant target proteins by aug codon reassignment in a methionine-auxotroph e. coli strain. ... | 2014 | 24434673 |
| heterologous expression of escherichia coli fructose-1,6-bisphosphatase in corynebacterium glutamicum and evaluating the effect on cell growth and l-lysine production. | fructose-1,6-bisphosphatase (fbpase), which is mainly used to supply nadph, has an important role in increasing l-lysine production by corynebacterium glutamicum. however, c. glutamicum fbpase is negatively regulated at the metabolic level. strains that overexpressed escherichia coli fructose-1,6-bisphosphatase in c. glutamicum were constructed, and the effects of heterologous fbpase on cell growth and l-lysine production during growth on glucose, fructose, and sucrose were evaluated. the hetero ... | 2014 | 24397720 |
| development and characterization of expression vectors for corynebacterium glutamicum. | in an attempt to develop a variety of expression vector systems for corynebacterium glutamicum, six types of promoters, including ptac, psod, psod with a conserved shine-dalgarno (sd) sequence from c. glutamicum, pilvc, pilvc with a conserved sd-1 (pilvc-m1), and pilvc with a conserved sd-2 (pilvc-m2), were cloned into a modified shuttle vector, pcxm48. according to analysis of promoter strength by quantitative reverse transcription pcr, psod and psod-m were superior to tac and ilvc promoters in ... | 2014 | 24169455 |
| aerobic production of succinate from arabinose by metabolically engineered corynebacterium glutamicum. | arabinose is considered as an ideal feedstock for the microbial production of value-added chemicals due to its abundance in hemicellulosic wastes. in this study, the arabad operon from escherichia coli was introduced into succinate-producing corynebacterium glutamicum, which enabled aerobic production of succinate using arabinose as sole carbon source. the engineered strain zx1 (pxarabad, peacsaglta) produced 74.4 mm succinate with a yield of 0.58 mol (mol arabinose)(-1), which represented 69.9% ... | 2014 | 24169202 |
| significance of arg3, arg54, and tyr58 of l-aspartate α-decarboxylase from corynebacterium glutamicum in the process of self-cleavage. | we have elucidated the significance of three key amino acid residues of l-aspartate α-decarboxylase that act remotely from its cleavage site for its functional self-cleavage as well as for its catalytic activity. these results provide useful fundamental information for engineering l-aspartate α-decarboxylase. l-aspartate α-decarboxylase (adc) from corynebacterium glutamicum, and encoded by pand, was cloned and expressed in escherichia coli and then purified. three amino acid residues were found ... | 2014 | 24104602 |
| succinic acid production from corn cob hydrolysates by genetically engineered corynebacterium glutamicum. | corynebacterium glutamicum wild type lacks the ability to utilize the xylose fractions of lignocellulosic hydrolysates. in the present work, we constructed a xylose metabolic pathway in c. glutamicum by heterologous expression of the xyla and xylb genes coming from escherichia coli. dilute-acid hydrolysates of corn cobs containing xylose and glucose were used as a substrate for succinic acid production by recombinant c. glutamicum nc-2. the results indicated that the available activated charcoal ... | 2014 | 24078255 |
| formaldehyde degradation in corynebacterium glutamicum involves acetaldehyde dehydrogenase and mycothiol-dependent formaldehyde dehydrogenase. | corynebacterium glutamicum, a gram-positive soil bacterium belonging to the actinomycetes, is able to degrade formaldehyde but the enzyme(s) involved in this detoxification process were not known. acetaldehyde dehydrogenase ald, which is essential for ethanol utilization, and fadh, characterized here as nad-linked mycothiol-dependent formaldehyde dehydrogenase, were shown to be responsible for formaldehyde oxidation since a mutant lacking ald and fadh could not oxidize formaldehyde resulting in ... | 2013 | 24065717 |
| electrophysiological characterization of the mechanosensitive channel msccg in corynebacterium glutamicum. | corynebacterium glutamicum msccg, also referred to as ncgl1221, exports glutamate when biotin is limited in the culture medium. msccg is a homolog of escherichia coli mscs, which serves as an osmotic safety valve in e. coli cells. patch-clamp experiments using heterogeneously expressed msccg have shown that msccg is a mechanosensitive channel gated by membrane stretch. although the association of glutamate secretion with the mechanosensitive gating has been suggested, the electrophysiological ch ... | 2013 | 24047987 |
| a wbla-binding protein, spia, involved in streptomyces oxidative stress response. | the streptomyces coelicolor wbla gene is known to play a negative role in both antibiotic biosynthesis and the expression of genes responding to oxidative stress. recently, whca, a wbla ortholog protein, was confirmed to interact with dioxygenase-encoding spia (stress protein interacting with whca) in corynebacterium glutamicum. we describe here the identification of a spia ortholog sco2553 protein (spiasc) that interacts with wbla in s. coelicolor. using heterologous expression in e. coli and i ... | 2013 | 23867703 |
| construction and application of an efficient multiple-gene-deletion system in corynebacterium glutamicum. | gene deletion techniques are important for modifying corynebacterium glutamicum, the bacterium for industrial production of amino acids. in this study, a novel multiple-gene-deletion system for c. glutamicum was developed. the system is composed of three plasmids pdtw109, pdtw201 and pdtw202. pdtw109 is a temperature-sensitive vector which harbors a cat gene under the tacm promoter, a cre gene under the tac promoter, an origin orie for replicating in escherichia coli, and another origin rep(ts) ... | 2013 | 23856168 |
| enhancing (l)-isoleucine production by thrabc overexpression combined with alat deletion in corynebacterium glutamicum. | l-isoleucine is synthesized from 2-ketobutyrate and pyruvate in corynebacterium glutamicum, and the supplies of these two precursors are important for l-isoleucine synthesis. c. glutamicum yilwδalat with alat gene deletion (encoding alanine aminotransferase, a principal enzyme for l-alanine synthesis) was constructed to increase intracellular pyruvate availability, and the thrabc genes from escherichia coli (encoding bifunctional aspartate kinase i-homoserine dehydrogenase i, homoserine kinase, ... | 2013 | 23813403 |
| the methylotrophic bacillus methanolicus mga3 possesses two distinct fructose 1,6-bisphosphate aldolases. | the thermotolerant gram-positive methylotroph bacillus methanolicus is able to grow with methanol, glucose or mannitol as a sole carbon and energy source. fructose 1,6-bisphosphate aldolase (fba), a key enzyme of glycolysis and gluconeogenesis, is encoded in the genome of b. methanolicus by two putative fba genes, the chromosomally located fba(c) and fba(p) on the naturally occurring plasmid pbm19. their amino acid sequences share 75 % identity and suggest a classification as class ii aldolases. ... | 2013 | 23760818 |
| strain optimization for efficient isobutanol production using corynebacterium glutamicum under oxygen deprivation. | microbial production of isobutanol is made difficult by the chemical's high cell toxicity. corynebacterium glutamicum, inherently one of the more isobutanol-tolerant industrial microorganisms, exhibits unprecedented productivity under oxygen deprivation, potentially allowing for high productivity of such toxic chemicals as isobutanol. here, we show that development of c. glutamicum strains proficient in isobutanol production depends not only on modulating the activity of 2-keto acid decarboxylas ... | 2013 | 23737329 |
| production of non-proteinogenic amino acids from α-keto acid precursors with recombinant corynebacterium glutamicum. | in the present work, corynebacterium glutamicum was metabolically engineered for the enantioselective synthesis of non-proteinogenic amino acids as valuable building blocks for pharmaceuticals and agrochemicals. the novel bio-catalytic activity of c. glutamicum was obtained by heterologous expression of the branched chain aminotransferase ilve from escherichia coli. upon this modification, the recombinant cells converted the α-keto acid precursor 2-(3-hydroxy-1-adamantyl)-2-oxoethanoic acid (hoa ... | 2013 | 23737264 |
| l-glutamate secretion by the n-terminal domain of the corynebacterium glutamicum ncgl1221 mechanosensitive channel. | the corynebacterium glutamicum ncgl1221 mechanosensitive channel mediates l-glutamate secretion by sensing changes in membrane tension caused by treatments such as biotin limitation and penicillin. the ncgl1221 protein has an n-terminal domain (1-286 a.a.) homologous to the escherichia coli mscs and a long c-terminal domain (287-533 a.a.) of unknown function. in order to investigate the role of the c-terminal domain in l-glutamate secretion, we constructed a series of c-terminally truncated muta ... | 2013 | 23649271 |
| histidine biosynthesis, its regulation and biotechnological application in corynebacterium glutamicum. | l-histidine biosynthesis is an ancient metabolic pathway present in bacteria, archaea, lower eukaryotes, and plants. for decades l-histidine biosynthesis has been studied mainly in escherichia coli and salmonella typhimurium, revealing fundamental regulatory processes in bacteria. furthermore, in the last 15 years this pathway has been also investigated intensively in the industrial amino acid-producing bacterium corynebacterium glutamicum, revealing similarities to e. coli and s. typhimurium, a ... | 2014 | 23617600 |
| crude glycerol-based production of amino acids and putrescine by corynebacterium glutamicum. | corynebacterium glutamicum possesses genes for glycerol kinase and glycerol-3-phosphate dehydrogenase that were shown to support slow growth with glycerol only when overexpressed from a plasmid. pure glycerol and crude glycerol from biodiesel factories were tested for growth of recombinant strains expressing glpf, glpk and glpd from escherichia coli. some, but not all crude glycerol lots served as good carbon sources. although the inhibitory compound(s) present in these crude glycerol lots remai ... | 2013 | 23562176 |
| enhanced production of l-phenylalanine in corynebacterium glutamicum due to the introduction of escherichia coli wild-type gene aroh. | metabolic engineering is a powerful tool which has been widely used for producing valuable products. for improving l-phenylalanine (l-phe) accumulation in corynebacterium glutamicum, we have investigated the target genes involved in the biosynthetic pathways. the genes involved in the biosynthesis of l-phe were found to be strictly regulated genes by feedback inhibition. as a result, overexpression of the native wild-type genes arof, arog or phea resulted in a slight increase of l-phe. in contra ... | 2013 | 23526182 |
| metabolic engineering of corynebacterium glutamicum to produce gdp-l-fucose from glucose and mannose. | wild-type corynebacterium glutamicum was metabolically engineered to convert glucose and mannose into guanosine 5'-diphosphate (gdp)-l-fucose, a precursor of fucosyl-oligosaccharides, which are involved in various biological and pathological functions. this was done by introducing the gmd and wcag genes of escherichia coli encoding gdp-d-mannose-4,6-dehydratase and gdp-4-keto-6-deoxy-d-mannose-3,5-epimerase-4-reductase, respectively, which are known as key enzymes in the production of gdp-l-fuco ... | 2013 | 23404100 |
| glutamate efflux mediated by corynebacterium glutamicum msccg, escherichia coli mscs, and their derivatives. | corynebacterium glutamicum is used in microbial biotechnology for the production of amino acids, in particular glutamate. the mechanism of glutamate excretion, however, is not yet fully understood. recently, evidence was provided that the ncgl1221 gene product from c. glutamicum atcc 13869, a mscs-type mechanosensitive efflux channel, is responsible for glutamate efflux [1]. the major difference of ncgl1221 and the homologous protein msccg of c. glutamicum atcc 13032 from escherichia coli mscs a ... | 2013 | 23313454 |
| transcriptional control of the f0f1-atp synthase operon of corynebacterium glutamicum: sigmah factor binds to its promoter and regulates its expression at different ph values. | corynebacterium glutamicum used in the amino acid fermentation industries is an alkaliphilic microorganism. its f(0)f(1)-atpase operon (atpbefhagdc) is expressed optimally at ph 9.0 forming a polycistronic (7.5 kb) and a monocistronic (1.2 kb) transcripts both starting upstream of the atpb gene. expression of this operon is controlled by the sigmah factor. the sigmah gene (sigh) was cloned and shown to be co-transcribed with a small gene, cg0877, encoding a putative anti-sigma factor. a mutant d ... | 2013 | 23298179 |
| metabolic engineering of industrial platform microorganisms for biorefinery applications--optimization of substrate spectrum and process robustness by rational and evolutive strategies. | bio-based production promises a sustainable route to myriads of chemicals, materials and fuels. with regard to eco-efficiency, its future success strongly depends on a next level of bio-processes using raw materials beyond glucose. such renewables, i.e., polymers, complex substrate mixtures and diluted waste streams, often cannot be metabolized naturally by the producing organisms. this particularly holds for well-known microorganisms from the traditional sugar-based biotechnology, including esc ... | 2013 | 23260271 |
| 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 ... | 2012 | 23134565 |
| 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 ... | 2012 | 23033959 |
| [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 ... | 2012 | 22916496 |
| 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 ... | 2012 | 22885668 |
| increased lysine production by flux coupling of the tricarboxylic acid cycle and the lysine biosynthetic pathway--metabolic engineering of the availability of succinyl-coa in corynebacterium glutamicum. | in this study, we demonstrate increased lysine production by flux coupling using the industrial work horse bacterium corynebacterium glutamicum, which was mediated by the targeted interruption of the tricarboxylic acid (tca) cycle at the level of succinyl-coa synthetase. the succinylase branch of the lysine production pathway functions as the bridging reaction to convert succinyl-coa to succinate in this aerobic bacterium. the mutant c. glutamicum δsuccd showed a 60% increase in the yield of lys ... | 2013 | 22871505 |
| 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, ... | 2012 | 22806862 |
| 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 ... | 2012 | 22785475 |
| 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 ... | 2012 | 22771937 |
| 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 ... | 2012 | 22759537 |
| 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 ... | 2012 | 22685153 |
| 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 ... | 2012 | 22682799 |
| exploring the allosteric mechanism of dihydrodipicolinate synthase by reverse engineering of the allosteric inhibitor binding sites and its application for lysine production. | dihydrodipicolinate synthase (dhdps, ec 4.2.1.52) catalyzes the first committed reaction of l-lysine biosynthesis in bacteria and plants and is allosterically regulated by l-lysine. in previous studies, dhdpss from different species were proved to have different sensitivity to l-lysine inhibition. in this study, we investigated the key determinants of feedback regulation between two industrially important dhdpss, the l-lysine-sensitive dhdps from escherichia coli and l-lysine-insensitive dhdps f ... | 2013 | 22644522 |
| 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 ... | 2012 | 22640862 |
| 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 ... | 2012 | 22588847 |
| [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. | 2012 | 22586995 |
| glycerol as a substrate for aerobic succinate production in minimal medium with corynebacterium glutamicum. | corynebacterium glutamicum, an established microbial cell factory for the biotechnological production of amino acids, was recently genetically engineered for aerobic succinate production from glucose in minimal medium. in this work, the corresponding strains were transformed with plasmid pvwex1-glpfkd coding for glycerol utilization genes from escherichia coli. this plasmid had previously been shown to allow growth of c. glutamicum with glycerol as sole carbon source. the resulting strains were ... | 2013 | 22513227 |
| 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 ... | 2012 | 22511122 |
| 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. ... | 2012 | 22497218 |
| 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 ... | 2012 | 22405039 |
| 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 ... | 2012 | 22370950 |
| 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 ... | 2012 | 22340668 |
| 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 ... | 2012 | 23113930 |
| effects of eliminating pyruvate node pathways and of coexpression of heterogeneous carboxylation enzymes on succinate production by enterobacter aerogenes. | lowering the ph in bacterium-based succinate fermentation is considered a feasible approach to reduce total production costs. newly isolated enterobacter aerogenes strain aj110637, a rapid carbon source assimilator under weakly acidic (ph 5.0) conditions, was selected as a platform for succinate production. our previous work showed that the δadhe/pck strain, developed from aj110637 with inactivated ethanol dehydrogenase and introduced actinobacillus succinogenes phosphoenolpyruvate carboxykinase ... | 2015 | 25416770 |
| metabolic engineering of corynebacterium glutamicum for the production of 3-hydroxypropionic acid from glucose and xylose. | 3-hydroxypropionic acid (3-hp) is a promising platform chemical which can be used for the production of various value-added chemicals. in this study,corynebacterium glutamicum was metabolically engineered to efficiently produce 3-hp from glucose and xylose via the glycerol pathway. a functional 3-hp synthesis pathway was engineered through a combination of genes involved in glycerol synthesis (fusion of gpd and gpp from saccharomyces cerevisiae) and 3-hp production (pducdegh from klebsiella pneu ... | 2017 | 27918882 |
| industrial production of 2,3-butanediol from the engineered corynebacterium glutamicum. | the platform chemical 2,3-butanediol (2,3-bdo) is a valuable product that can be converted into several petroleum-based chemicals via simple chemical reactions. here, we produced 2,3-bdo with the non-pathogenic and rapidly growing corynebacterium glutamicum. to enhance the 2,3-bdo production capacity of c. glutamicum, we introduced buda encoding acetolactate decarboxylase from klebsiella pneumoniae, a powerful 2,3-bdo producer. additionally, budb (encoding α-acetolactate synthase) and budc (enco ... | 2015 | 26113219 |
| 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 ... | 2012 | 22940340 |
| directed evolution and mutagenesis of glutamate decarboxylase from lactobacillus brevis lb85 to broaden the range of its activity toward a near-neutral ph. | glutamate decarboxylase (gad) transforms l-glutamate into γ-aminobutyric acid (gaba) with the consumption of a proton. gad derived from lactic acid bacteria exhibits optimum activity at ph 4.0-5.0 and significantly loses activity at near-neutral ph. to broaden the active range of the gad gadb1 from lactobacillus brevis lb85 toward a near-neutral ph, irrational design using directed evolution and rational design using site-specific mutagenesis were performed. for directed evolution of gadb1, a se ... | 2014 | 24910334 |
| enhancement of γ-aminobutyric acid production in recombinant corynebacterium glutamicum by co-expressing two glutamate decarboxylase genes from lactobacillus brevis. | γ-aminobutyric acid (gaba), a non-protein amino acid, is a bioactive component in the food, feed and pharmaceutical fields. to establish an effective single-step production system for gaba, a recombinant corynebacterium glutamicum strain co-expressing two glutamate decarboxylase (gad) genes (gadb1 and gadb2) derived from lactobacillus brevis lb85 was constructed. compared with the gaba production of the gadb1 or gadb2 single-expressing strains, gaba production by the gadb1-gadb2 co-expressing st ... | 2013 | 23928903 |
| heme derived from corynebacterium glutamicum: a potential iron additive for swine and an electron carrier additive for lactic acid bacterial culture. | to investigate the potential applications of bacterial heme, aminolevulinic acid synthase (hema) was expressed in a corynebacterium glutamicum ha strain that had been adaptively evolved against oxidative stress. the red pigment from the constructed strain was extracted and it exhibited the typical heme absorbance at 408 nm from the spectrum. to investigate the potential of this strain as an iron additive for swine, a prototype feed additive was manufactured in pilot scale by culturing the strain ... | 2017 | 28035120 |
| glucose consumption rate critically depends on redox state in corynebacterium glutamicum under oxygen deprivation. | rapid sugar consumption is important for the microbial production of chemicals and fuels. here, we show that overexpression of the nadh dehydrogenase gene (ndh) increased glucose consumption rate in corynebacterium glutamicum under oxygen-deprived conditions through investigating the relationship between the glucose consumption rate and intracellular nadh/nad(+) ratio in various mutant strains. the nadh/nad(+) ratio was strongly repressed under oxygen deprivation when glucose consumption was acc ... | 2015 | 25808520 |