| production of riboflavin by metabolically engineered corynebacterium ammoniagenes. | improved strains for the production of riboflavin (vitamin b2) were constructed through metabolic engineering using recombinant dna techniques in corynebacterium ammoniagenes. a c. ammoniagenes strain harboring a plasmid containing its riboflavin biosynthetic genes accumulated 17-fold as much riboflavin as the host strain. in order to increase the expression of the biosynthetic genes, we isolated dna fragments that had promoter activities in c. ammoniagenes. when the dna fragment (p54-6) showing ... | 2000 | 10919325 |
| amino acid catabolism in cheese-related bacteria: selection and study of the effects of ph, temperature and nacl by quadratic response surface methodology. | to screen the cystathionine lyase and l-methionine aminotransferase activities of cheese-related bacteria (lactococci, non-starter lactobacilli and smear bacteria) and to determine the individual and interactive effects of temperature, ph and nacl concentration on selected enzyme activities. | 2001 | 11473596 |
| crystal structure of the di-iron/radical protein of ribonucleotide reductase from corynebacterium ammoniagenes. | ribonucleotide reductase (rnr) is the enzyme performing de novo production of the four deoxyribonucleotides needed for dna synthesis. all mammals as well as some prokaryotes express the class i enzyme which is an alpha(2)beta(2) protein. the smaller of the homodimers, denoted r2, contains a di-iron carboxylate site which, upon reaction with molecular oxygen, generates a stable tyrosyl radical needed for catalysis. the three-dimensional structure of the oxidized class ib rnr r2 from corynebacteri ... | 2002 | 11802741 |
| [relationship between the synthesis of a new stress response component and bacterial cell metabolism]. | various stress factors (incubation with redox-cycling agents, ozonization, heat shock) that induced accumulation of 2-c-methyl-d-erythritol-2,4-cyclopyrophosphate (mec) were also shown to induce various alterations of the phospholipid composition in three microbial species: corynebacterium ammoniagenes, micrococcus luteus, and staphylococcus aureus. the influence of adding 10 carbohydrates to the growth medium on mec accumulation by c. ammoniagenes cells was tested. only glucose and mannose exer ... | 1995 | 8544784 |
| [effect of synthetic surfactants on some biological properties of non-pathogenic species of the genus corynebacterium]. | the influence of cationic, anionic and non-ionic synthetic surfactants on some biological properties of different representatives of the following species corynebacterium glutamicum, corynebacterium ammoniagenes, corynebacterium vitaeruminis, corynebacterium variabile and strain corynebacterium sp. (brevibacterium stationis) ukm as-719 has been investigated. it has been shown that the action of surfactants is accompanied by the change of cell morphology and loss of ability for gram-staining, as ... | 2006 | 16869145 |
| [study on the kinetics of immobilized cells of brevibacterium ammoniagenes ma-2 and brevibacterium flavum ma-3]. | the kinetics of immobilized cells of brevibacterium ammoniagenes ma-2 and brevibacterium flavum ma-3 cells were studied. by means of both a theoretical analysis of diffusion in the gel particles and an experimental determination of apparent kinetic parameters, the intrinsic kinetic parameters of immobilized cells of b. ammoniagenes ma-2 and b. flavum ma-3 cells were obtained. | 2002 | 12148291 |
| significance of the non-oxidative route of the pentose phosphate pathway for supplying carbon to the purine-nucleotide pathway in corynebacterium ammoniagenes. | to evaluate the strategy of supplying ribose 5-phosphate to the purine-nucleotide pathway exclusively via the nonoxidative route, the glucose 6-phosphate dehydrogenase gene zwf was disrupted in inosine- and 5'-xanthylic acid-producers of corynebacterium ammoniagenes. in both producers, interruption of the oxidative route caused a decrease in production yields of about 50%. attempts to increase the capacity of the nonoxidative route through overexpression of the transketolase or transaldolase gen ... | 2003 | 12612788 |
| corynebacterium ammoniagenes class ib ribonucleotide reductase: transcriptional regulation of an atypical genomic organization in the nrd cluster. | ribonucleotide reductases (rnrs) are a family of complex enzymes that play an essential role in all organisms because they catalyse de novo synthesis of deoxyribonucleotides required for dna replication and repair. three different classes of rnr have been described according to their metal cofactors and organic radicals. class ib rnr is encoded in four different genes (nrdh, nrdi, nrde and nrdf) organized in an operon. the authors previously cloned and sequenced the genes encoding the active cla ... | 2003 | 12686643 |
| 31p nmr studies of energy metabolism in xanthosine-5'-monophosphate overproducing corynebacterium ammoniagenes. | corynebacterium ammoniagenes is an overproducer of xanthosine-5'-monophosphate (xmp) by consuming either glcose (glc) or glutamic acid (glu). its energy metabolism was studied in vivo using 31p nmr spectroscopy coupled with a circulating fermentation system (cfs). cfs enabled us to validate directly the cellular dependency on carbon sources and changes in biomolecules produced according to alterations in the cellular energetic status. for the most efficient xmp production, the glutamic acid and ... | 2003 | 12787028 |
| arrest of cell cycle by inhibition of ribonucleotide reductase induces accumulation of nad+ by mn2+-supplemented growth of corynebacterium ammoniagenes. | cell division of the wild type strain corynebacterium (formerly brevibacterium) ammoniagenes atcc 6872 which requires 1 microm mn2+ for balanced growth was inhibited by addition of 20 mm hydroxyurea (hu) or 10 mm p-methoxyphenol (mp) to a mn2+-supplemented fermentation medium at an appropriate time. scanning electron microscopy (sem) showed a restricted elongation characteristic of arrest of the cell cycle in coryneform bacteria. the cultures treated with hu or mp had, respectively, a fourfold o ... | 2003 | 12882290 |
| characterization of developmental colony formation in corynebacterium glutamicum. | we report that corynebacterium glutamicum colonies exhibit a developmental transition in culture. when cultured on a routinely used complete medium (cm2b), this bacterium first formed a flat translucent colony. subsequently, some parts of this colony expanded to form small spherical yellow colonies that finally developed into a single large yellow colony. the small flat colony consisted of long thick cells, which were occasionally v or y shaped, while the large yellow colony consisted of short s ... | 2008 | 18696061 |
| isolation of transcription initiation signals from corynebacterium ammoniagenes and comparison of their gene expression levels in c. ammoniagenes and escherichia coli. | with the aim of isolating transcription initiation signals, random sau3ai fragments of corynebacterium ammoniagenes atcc 6872 were cloned into the promoter-probe plasmid, pekplcm, and screened for promoter activity by chloramphenicol resistance of transformed escherichia coli cells. representative 22 promoter clones were analysed in c. ammoniagenes by its nucleotide sequences and promoter activities were measured by chloramphenicol acetyltransferase (cat) assay. activities of cat were between 0. ... | 2003 | 14514058 |
| [effect of antiseptics and redox-cycling agents on corynebacterium ammoniagenes and related microorganisms in relation to synthesis of a new macroergic compound]. | sublethal concentration of the antiseptic composition desoxon-1 was shown to provoke in cells of corinebacterium ammoniagenes in a liquid medium the biosynthesis and accumulation of a novel macroergic 2-methylbutane-1,2,3,4-tetraol-2,4-cyclopyrophosphate. this substance is also synthesized when c. ammoniagenes is cultivated in a solid agar medium supplemented with benzylviologen. cells preloaded with the new cyclopyrophosphate maintain its content when treated with 4% phenol, dp-2, desoxon-1 or ... | 1994 | 7990732 |
| the open reading frame present in the nrdef cluster of corynebacterium ammoniagenes is a transcriptional regulator belonging to the gntr family. | in this work we have identified the cagntr gene, present between the nrde and nrdf genes of corynebacterium ammoniagenes, as a transcriptional regulator belonging to the gntr family. this gene encodes a transcriptional factor actively transcribed in the opposite direction relative to the nrdhief operon. it is expressed in a cell-culture-dependent fashion and, although the members of this family have been reported to regulate transcription of genes found within their vicinity, we have shown that ... | 2004 | 15386096 |
| the cmar gene of corynebacterium ammoniagenes performs a novel regulatory role in the metabolism of sulfur-containing amino acids. | a novel regulatory gene, which performs an essential function in sulfur metabolism, has been identified in corynebacterium ammoniagenes and was designated cmar (cysteine and methionine regulator in c. ammoniagenes). the cmar-disrupted strain (deltacmar) lost the ability to grow on minimal medium, and was identified as a methionine and cysteine double auxotroph. the mutant strain proved unable to convert cysteine to methionine (and vice versa), and lost the ability to assimilate and reduce sulfat ... | 2009 | 19383689 |
| s434f in nrde generates the thermosensitive phenotype of corynebacterium ammoniagenes ch31 and enhances thermolability by increasing the surface hydrophobicity of the nrde(ts) protein. | the thermosensitive phenotype of strain ch31, a derivative of corynebacterium ammoniagenes atcc 6872, was allocated by cloning, sequencing, and genetic complementation to a single c-->t exchange in the nrde (nucleotide reduction) gene at nucleotide 1301. protein modeling indicates the impaired surface hydrophobicity of nrde(ts) due to the s434f transition. | 2005 | 16151152 |
| large-scale production of the carbohydrate portion of the sialyl-tn epitope, alpha-neup5ac-(2-->6)-d-galpnac, through bacterial coupling. | alpha-neup5ac-(2-->6)-d-galpnac, the carbohydrate portion of sialyl-tn epitope of the tumor-associated carbohydrate antigen, was prepared by a whole-cell reaction through the combination of recombinant escherichia coli strains and corynebacterium ammoniagenes. two recombinant e. coli strains overexpressed the cmp-neup5ac biosynthetic genes and the alpha-(2-->6)-sialyltransferase gene of photobacterium damsela. c. ammoniagenes contributed to the production of utp from orotic acid. alpha-neup5ac-( ... | 2001 | 11269395 |
| identification of yace (coae) as the structural gene for dephosphocoenzyme a kinase in escherichia coli k-12. | dephosphocoenzyme a (dephospho-coa) kinase catalyzes the final step in coenzyme a biosynthesis, the phosphorylation of the 3'-hydroxy group of the ribose sugar moiety. wild-type dephospho-coa kinase from corynebacterium ammoniagenes was purified to homogeneity and subjected to n-terminal sequence analysis. a blast search identified a gene from escherichia coli previously designated yace encoding a highly homologous protein. amplification of the gene and overexpression yielded recombinant dephosp ... | 2001 | 11292795 |
| kinetic resolutions of indan derivatives using bacteria. | racemic indan derivatives have been resolved by the hydrolysis of amide bonds using corynebacterium ammoniagenes ifo12612 to produce (s)-amine and (r)-amides. in the kinetic resolution of 1 (n-12-(6-methoxy-indan-1-yl)ethyl]acetamide), it was possible to run the reaction to 44% conversion on a 10-g scale, obtaining (s)-amine 4 ((s)-2-(6-methoxy-indan-1-yl)ethylamine) at >99% enantiomeric excess (ee) and (r)-1 at 98% ee. | 2002 | 11999429 |
| the regulator rama influences cmyta transcription and cell morphology of corynebacterium ammoniagenes. | rama plays a regulatory role for acetate utilization and s-layer biosynthesis in corynebacterium glutamicum. looking for any additional role, the function of rama was analyzed in corynebacterium ammoniagenes, which is closely related to c. glutamicum. in this study, we showed that the deltarama mutant constructed by a markerless knockout strategy possessed increased cell surface hydrophobicity, leading to the formation of aggregated cell masses in liquid media. in addition, the mutant exhibited ... | 2010 | 20107993 |
| corynebacterium mooreparkense sp. nov. and corynebacterium casei sp. nov., isolated from the surface of a smear-ripened cheese. | ten isolates each of two different bacterial species isolated from the surface of a smear-ripened cheese were found to exhibit many characteristics of the genus corynebacterium. the isolates were gram-positive, catalase-positive, non-spore-forming rods that did not undergo a rod/coccus transformation when grown on complex media. chemotaxonomic investigation revealed that the strains belonged unambiguously to the genus corynebacterium. their cell walls contained arabinose, galactose and short-cha ... | 2001 | 11411705 |
| effect of transketolase modifications on carbon flow to the purine-nucleotide pathway in corynebacterium ammoniagenes. | transketolase, one of the enzymes in the nonoxidative branch of the pentose phosphate pathway, operates to shuttle ribose 5-phosphate and glycolytic intermediates together with transaldolase, and might be involved in the availability of ribose 5-phosphate, a precursor of nucleotide biosynthesis. the tkt and tal genes encoding transketolase and transaldolase, respectively, were cloned from the typical nucleotide- and nucleoside-producing organism corynebacterium ammoniagenes by a pcr approach usi ... | 2001 | 11601619 |
| cloning and expression of beta1,4-galactosyltransferase gene from helicobacter pylori. | helicobacter pylori, which is a human pathogen associated with gastric and duodenal ulcer, has been shown to express human oncofetal antigens lewis x and lewis y. although the mammalian glycosyltransferases that synthesize these structures are well characterized, little is known about the corresponding bacterial enzymes. we report that a novel beta1,4-galactosyltransferase gene (hpgalt) involved in the biosynthesis of lipopolysaccharides in h. pylori has been cloned and expressed in escherichia ... | 2000 | 10929007 |
| nrdh-redoxin of corynebacterium ammoniagenes forms a domain-swapped dimer. | nrdh-redoxins constitute a family of small redox proteins, which contain a conserved cxxc sequence motif, and are characterized by a glutaredoxin-like amino acid sequence but a thioredoxin-like activity profile. here we report the structure of corynebacterium ammoniagenes nrdh at 2.7 a resolution, determined by molecular replacement using e. coli nrdh as model. the structure is the first example of a domain-swapped dimer from the thioredoxin family. the domain-swapped structure is formed by an i ... | 2004 | 15103625 |
| cloning and characterization of a sigma 70 homologue gene, siga from corynebacterium ammoniagenes. | a sigma 70-like gene, siga, has been identified from corynebacterium ammoniagenes. the siga gene encodes a polypeptide of 467 amino acids with a calculated molecular mass of 52036 da. the deduced amino acid sequence preserves the common motifs of the primary sigma factors and shows very high similarity to those of siga (sigmaa) homologues from high g+c gram-positive bacteria, which suggest that the siga gene encodes the primary sigma factor. the siga gene is transcribed as a monocistronic mrna o ... | 2004 | 15168860 |
| structural and mutational studies of the carboxylate cluster in iron-free ribonucleotide reductase r2. | the r2 protein of ribonucleotide reductase features a di-iron site deeply buried in the protein interior. the apo form of the r2 protein has an unusual clustering of carboxylate side chains at the empty metal-binding site. in a previous study, it was found that the loss of the four positive charge equivalents of the diferrous site in the apo protein appeared to be compensated for by the protonation of two histidine and two carboxylate side chains. we have studied the consequences of removing and ... | 2004 | 15196041 |
| characterization of the cell surface protein gene of corynebacterium ammoniagenes. | three dominant cell surface proteins of corynebacterium ammoniagenes atcc 6872 were identified in the cell wall fraction. the cspa gene, which encodes one of the major cell surface proteins, was cloned using the n-terminal amino acid sequence of the protein. then the cloned chromosomal fragment containing the cspa gene was sequenced and was shown to encode a mature polypeptide of 333 amino acids with a molecular mass of 36654 da. the amino acid sequence of the cspa gene showed similarity to the ... | 2001 | 11750067 |
| genes encoding ribonucleoside hydrolase 1 and 2 from corynebacterium ammoniagenes. | two kinds of nucleoside hydrolases (nhs) encoded by rih1 and rih2 were cloned from corynebacterium ammoniagenes using deod- and gsk-defective escherichia coli. sequence analysis revealed that nh 1 was a protein of 337 aa with a deduced molecular mass of 35,892 da, whereas nh 2 consisted of 308 aa with a calculated molecular mass of 32 310 da. experiments with crude extracts of iptg-induced e. coli cgsc 6885(ptnu23) and 6885(ptni12) indicated that the rih1 enzyme could catalyse the hydrolysis of ... | 2006 | 16549679 |
| a functional homing endonuclease in the bacillus anthracis nrde group i intron. | the essential bacillus anthracis nrde gene carries a self-splicing group i intron with a putative homing endonuclease belonging to the giy-yig family. here, we show that the nrde pre-mrna is spliced and that the homing endonuclease cleaves an intronless nrde gene 5 nucleotides (nt) upstream of the intron insertion site, producing 2-nt 3' extensions. we also show that the sequence required for efficient cleavage spans at least 4 bp upstream and 31 bp downstream of the cleaved coding strand. the p ... | 2007 | 17496101 |
| overproduction of nad+ and 5'-inosine monophosphate in the presence of 10 microm mn2+ by a mutant of corynebacterium ammoniagenes with thermosensitive nucleotide reduction (nrd(ts)) after temperature shift. | corynebacterium ammoniagenes strain ch31 is thermosensitive due to a mutation in nucleotide reduction ( nrd(ts)). the strain was examined for nucleotide overproduction upon shifting the culture temperature to a range of elevated temperatures. no overproduction of nad(+) was detected in the control maintained at 27 degrees c whereas nad(+) was accumulated extracellularily by strain ch31 at 37 degrees c and at 40 degrees c. as a result of the temperature shift, division-inhibited cells displayed o ... | 2004 | 15340797 |
| production of uridine 5'-monophosphate by corynebacterium ammoniagenes atcc 6872 using a statistically improved biocatalytic process. | attempts were made with success to develop a two-step biocatalytic process for uridine 5'-monophosphate (ump) production from orotic acid by corynebacterium ammoniagenes atcc 6872: the strain was first cultivated in a high salt mineral medium, and then cells were harvested and used as the catalyst in the ump production reaction. effects of cultivation and reaction conditions on ump production were investigated. the cells exhibited the highest biocatalytic ability when cultivated in a medium cont ... | 2007 | 17520248 |
| autoinduction of a genetic locus encoding putative acyltransferase in corynebacterium glutamicum. | a genetic locus, encoding putative acyltransferase, was induced by autoinducers in corynebacterium glutamicum. the autoinducers were maximally produced by the bacterium after 24 h culture. those molecules are resistant to proteinase k treatment (300 μg ml(-1)) for 30 min at 37°c or at 121°c for 15 min, and remained stable after extensive storage at 4°c. autoinducers in the cell-free culture fluids from corynebacterium ammoniagenes and pseudomonas aeruginosa also induced the expression of acyltra ... | 2011 | 20821248 |
| orotate phosphoribosyltransferase from corynebacterium ammoniagenes lacking a conserved lysine. | the pyre gene, encoding orotate phosphoribosyltransferase (oprtase), was cloned by nested pcr and colony blotting from corynebacterium ammoniagenes atcc 6872, which is widely used in nucleotide production. sequence analysis shows that there is a lack of an important conserved lysine (lys 73 in salmonella enterica serovar typhimurium oprtase) in the c. ammoniagenes oprtase. this lysine has been considered to contribute to the initiation of catalysis. the enzyme was overexpressed and purified from ... | 2007 | 17921291 |
| secretion of streptomyces mobaraensis pro-transglutaminase by coryneform bacteria. | we previously reported on the secretion of streptomyces mobaraensis transglutaminase by corynebacterium glutamicum atcc13869 (formerly classified as brevibacterium lactofermentum). in the present work, we investigated whether any other coryneform bacteria showed higher productivity than c. glutamicum atcc13869. we found that most coryneform species secreted pro-transglutaminase efficiently. moreover, we confirmed that corynebacterium ammoniagenes atcc6872 produced about 2.5 g/l pro-transglutamin ... | 2008 | 18219481 |
| production of nadp by immobilized cells with nad kinase. | by the radiation-copolymerization method with polyethylene glycoldimethacrylate (pgd) as a main polymerizable reagent, microbial cells of brevibacterium ammoniagenes were immobilized with high specific activity of nad kinase and high mechanical strength. the reagents used for the immobilization such as pgd, polyvinyl alcohol (pva), and n,n'-methylenebisacrylamide (bis) did not inversely affect the enzyme activity. freezing and irradiation treatment of the cell-reagent solution did not inactivate ... | 1982 | 18546376 |
| structural analysis of fad synthetase from corynebacterium ammoniagenes. | the prokaryotic fad synthetase family - a group of bifunctional enzymes that catalyse riboflavin phosphorylation and fmn adenylylation within a single polypeptide chain- was analysed in terms of sequence and structure. | 2008 | 18811972 |
| the puzzle of ligand binding to corynebacterium ammoniagenes fad synthetase. | in bacteria, riboflavin phosphorylation and subsequent conversion of fmn into fad are carried out by fad synthetase, a single bifunctional enzyme. both reactions require atp and mg(2+). the n-terminal domain of fad synthetase appears to be responsible for the adenylyltransferase activity, whereas the c-terminal domain would be in charge of the kinase activity. binding to corynebacterium ammoniagenes fad synthetase of its products and substrates, as well as of several analogues, is analyzed. bind ... | 2009 | 19136717 |
| entrapment of live microbial cells in electropolymerized polyaniline and their use as urea biosensor. | the lyophilized biomass of bacterium brevibacterium ammoniagenes was immobilized in polystyrene sulphonate-polyaniline (pss-pani) conducting polymer on a pt twin wire electrode by potentiostatic electropolymerization. the bacterial cells retained their viability as well as urease activity under entrapped state, as confirmed with bacterial live-dead fluorescent assay and enzymatic assays. the entrapped cells were visualized using scanning electron microscope. the immobilized cells were used as a ... | 2009 | 19230647 |
| assignment of brevibacterium stationis (zobell and upham 1944) breed 1953 to the genus corynebacterium, as corynebacterium stationis comb. nov., and emended description of the genus corynebacterium to include isolates that can alkalinize citrate. | brevibacterium stationis atcc 14403(t), corynebacterium ammoniagenes atcc 6872 and two clinical isolates were found to form a single taxon group consistent with the genus corynebacterium, designated here as corynebacterium stationis comb. nov. the type strain of corynebacterium stationis is atcc 14403(t) =ccug 43497( t) =cip 104228(t) =dsm 20302(t) =nbrc 12144(t) =jcm 11611(t) =vkm b-1228(t). these strains can utilize citrate; therefore, inclusion of c. stationis requires that the description of ... | 2010 | 19661509 |
| [properties of 2-c-methyl-d-erythritol 2,4-cyclopyrophosphate--an intermediate in the non-mevalonate isoprenoid biosynthesis]. | extraction and purification from the biomass of corynebacterium ammoniagenes of 2-c-methyl-d-erhythritol 2,4-cyclopyrophosphate (mec) was associated with its spontaneous transformation into a number of derivatives (which was due to pyrophosphate bond lability and the formation of complexes with metals). these derivatives included 1,2-cyclophospho-4-phosphate, 2,4-diphosphate, 2,3-cyclophosphate, 1,4-diphosphate, and 3,5-diphosphate (identified by 1h, 31p, and 13c nmr spectroscopy) and accounted ... | 2003 | 14593871 |
| crystallization and preliminary x-ray analysis of the small subunit (r2f) of native ribonucleotide reductase from corynebacterium ammoniagenes. | ribonucleotide reduction, the unique step in dna-precursor biosynthesis, involves radical-dependent redox chemistry and diverse metallo-cofactors. the metallo-cofactor (r2f) encoded by the nrdf (nucleotide reduction) gene in corynebacterium ammoniagenes atcc 6872 was isolated after homologous expression and a new crystal form of ribonucleotide reductase r2f was obtained. r2f was crystallized at 277 k using the vapour-diffusion method with peg as the precipitating agent. a data set was collected ... | 2009 | 19724122 |
| microbial synthesis of triacetic acid lactone. | native g2ps1-encoded 2-pyrone synthase (2-ps) from gerbera hybrida, a mutant brevibacterium ammoniagenes fatty acid synthase b (fas-b) and two different mutants of penicillium patulum 6-methylsalycilic acid synthase (6-msas) are examined to identify the best enzyme to recruit for the microbial synthesis of triacetic acid lactone (tal). to identify the best microbial host for these evaluations, the native tal-synthesizing activity of g2ps1-encoded 2-ps is expressed in recombinant escherichia coli ... | 2006 | 16245348 |
| the manganese-containing ribonucleotide reductase of corynebacterium ammoniagenes is a class ib enzyme. | ribonucleotide reductases (rnrs) are key enzymes in living cells that provide the precursors of dna synthesis. the three characterized classes of rnrs differ by their metal cofactor and their stable organic radical. we have purified to near homogeneity the enzymatically active mn-containing rnr of corynebacterium ammoniagenes, previously claimed to represent a fourth rnr class. n-terminal and internal peptide sequence analyses clearly indicate that the c. ammoniagenes rnr is a class ib enzyme. i ... | 1998 | 9468481 |
| [interaction of bacteria with mercuric compounds]. | we investigated the interaction of mercuric compounds with the bacteria corynebacterium ammoniagenes, micrococcus luteus, and mycobacterium smegmatus capable of producing hydroxylamines (r-noh) and 2-c-methyl-d-erythritol-2,4-cyclopyrophosphate (mecp), which are prone to form free radicals. the interaction of these substances with hg2+ ions and their dynamics during the mercuric poisoning of bacteria was studied by epr and nmr. under stress conditions induced by lowering ph or generation of acti ... | 2000 | 11314647 |
| production of coenzyme a by a mutant of brevibacterium ammoniagenes resistant to oxypantetheine. | for improved production of coenzyme a (coa), a mutant of brevibacterium ammoniagenes ifo127071 resistant to oxypantetheine, the corresponding oxygen analog of pantetheine, was obtained. in the mutant, activity of pantothenate kinase (ec 2.7.1.33), the first-step enzyme for the biosynthesis of coa from pantothenic acid, l-cysteine, and atp, was about threefold higher than that in the parent strain. as the main regulation mechanism of coa biosynthesis in this bacterium is negative feedback inhibit ... | 1984 | 16346675 |
| internal lipid synthesis and vesicle growth as a step toward self-reproduction of the minimal cell. | one of the major properties of the semi-synthetic minimal cell, as a model for early living cells, is the ability to self-reproduce itself, and the reproduction of the boundary layer or vesicle compartment is part of this process. a minimal bio-molecular mechanism based on the activity of one single enzyme, the fas-b (fatty acid synthase) type i enzyme from brevibacterium ammoniagenes, is encapsulated in 1-palmitoyl-2oleoyl-sn-glycero-3-phosphatidylcholine (popc) liposomes to control lipid synth ... | 2009 | 19957048 |
| crystallization and preliminary x-ray diffraction studies of fad synthetase from corynebacterium ammoniagenes. | fad synthetase from corynebacterium ammoniagenes (cafads), a prokaryotic bifunctional enzyme that catalyses the phosphorylation of riboflavin as well as the adenylylation of fmn, has been crystallized using the hanging-drop vapour-diffusion method at 277 k. diffraction-quality cubic crystals of native and selenomethionine-labelled (semet-cafads) protein belonged to the cubic space group p2(1)3, with unit-cell parameters a = b = c = 133.47 a and a = b = c = 133.40 a, respectively. data sets for n ... | 2009 | 20054130 |
| oligomeric state in the crystal structure of modular fad synthetase provides insights into its sequential catalysis in prokaryotes. | the crystal structure of the modular flavin adenine dinucleotide (fad) synthetase from corynebacterium ammoniagenes has been solved at 1.95 a resolution. the structure of c. ammoniagenes fad synthetase presents two catalytic modules-a c-terminus with atp-riboflavin kinase activity and an n-terminus with atp-flavin mononucleotide (fmn) adenylyltransferase activity-that are responsible for the synthesis of fad from riboflavin in two sequential steps. in the monomeric structure, the active sites fr ... | 2010 | 20471397 |
| a tyrosyl-dimanganese coupled spin system is the native metalloradical cofactor of the r2f subunit of the ribonucleotide reductase of corynebacterium ammoniagenes. | the x-ray crystallographic structure of the native r2f subunit of the ribonucleotide reductase (rnr) of corynebacterium ammoniagenes atcc 6872 is reported, with a resolution of 1.36 a. the metal site contains an oxo/hydroxo-bridged manganese dimer, located near a tyrosine residue (y115). the coordination of the manganese dimer and its distance to a nearby tyrosine residue resemble the di-iron metalloradical cofactor of class i rnr from escherichia coli . multifrequency epr measurements of the hi ... | 2010 | 20698687 |
| rational pathway engineering of type i fatty acid synthase allows the biosynthesis of triacetic acid lactone from d-glucose in vivo. | metabolic pathway engineering is a powerful tool to synthesize structurally diverse and complex chemicals via genetic manipulation of multistep catalytic systems involved in cell metabolism. here, we report the rational design of a fatty acid biosynthetic pathway, brevibacterium ammoniagenes fatty acid synthase b (fas-b), that allows the microbial synthesis of triacetic acid lactone (tal) from an inexpensive feedstock, d-glucose. tal can be chemically converted to phloroglucinol, which is a core ... | 2004 | 15070368 |
| microbial production of n-acetylneuraminic acid by genetically engineered escherichia coli. | previously, we described the production of n-acetylneuraminic acid (neuac) from n-acetylglucosamine (glcnac) in a system combining recombinant escherichia coli expressing glcnac 2-epimerase (slr1975), e. coli expressing neuac synthetase (neub), and corynebacterium ammoniagenes. however, this system was unsuitable for large-scale production because of its complexity and low productivity. to overcome these problems, we constructed a recombinant e. coli simultaneously overexpressing slr1975 and neu ... | 2010 | 20971455 |
| mycobacterium tuberculosis acyl carrier protein synthase adopts two different ph-dependent structural conformations. | the crystal structures of acyl carrier protein synthase (acps) from mycobacterium tuberculosis (mtb) and corynebacterium ammoniagenes determined at ph 5.3 and ph 6.5, respectively, are reported. comparison of the mtb apo-acps structure with the recently reported structure of the mtb acps-adp complex revealed that acps adopts two different conformations: the orthorhombic and trigonal space-group structures show structural differences in the +¦2 helix and in the conformation of the +¦3-+¦4 connect ... | 2011 | 21697604 |
| detection of a quaternary organization into dimer of trimers of corynebacterium ammoniagenes fad synthetase at the single-molecule level and at the in cell level. | biochemical characterization of corynebacterium ammoniagenes fads (cafads) pointed to certain confusion about the stoichiometry of this bifunctional enzyme involved in the production of fmn and fad in prokaryotes. resolution of its crystal structure suggested that it might produce a hexameric ensemble formed by a dimer of trimers. we used atomic force microscopy (afm) to direct imaging single cafads molecules bound to mica surfaces, while preserving their catalytic properties. afm allowed solvin ... | 2013 | 23291469 |
| quantitation of intracellular purine intermediates in different corynebacteria using electrospray lc-ms/ms. | intermediates of the purine biosynthesis pathway play key roles in cellular metabolism including nucleic acid synthesis and signal mediation. in addition, they are also of major interest to the biotechnological industry as several intermediates either possess flavor-enhancing characteristics or are applied in medical therapy. in this study, we have developed an analytical method for quantitation of 12 intermediates from the purine biosynthesis pathway including important nucleotides and their co ... | 2012 | 22960872 |
| 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 |
| the trimer interface in the quaternary structure of the bifunctional prokaryotic fad synthetase from corynebacterium ammoniagenes. | bifunctional fad synthetases (fadss) fold in two independent modules; the c-terminal riboflavin kinase (rfk) catalyzes the rfk activity, while the n-terminal fmn-adenylyltransferase (fmnat) exhibits the fmnat activity. the search for macromolecular interfaces in the corynebacterium ammoniagenes fads (cafads) crystal structure predicts a dimer of trimers organization. within each trimer, a head-to-tail arrangement causes the rfk and fmnat catalytic sites of the two neighboring protomers to approa ... | 2017 | 28341845 |
| structural insights into the synthesis of fmn in prokaryotic organisms. | riboflavin kinases (rfks) catalyse the phosphorylation of riboflavin to produce fmn. in most bacteria this activity is catalysed by the c-terminal module of a bifunctional enzyme, fad synthetase (fads), which also catalyses the transformation of fmn into fad through its n-terminal fmn adenylyltransferase (fmnat) module. the rfk module of fads is a homologue of eukaryotic monofunctional rfks, while the fmnat module lacks homologyto eukaryotic enzymes involved in fad production. previously, the cr ... | 2015 | 26627660 |
| synthesis and application of isotopically labeled flavin nucleotides. | flavin nucleotides, i.e. flavin mononucleotide (fmn) and flavin adenine dinucleotide (fad), are utilized as prosthetic groups and/or substrates by a myriad of proteins, ranging from metabolic enzymes to light receptors. isotopically labeled flavins have served as invaluable tools in probing the structure and function of these flavoproteins. here we present an enzymatic synthesis of several radio- and stable-isotope labeled flavin nucleotides from commercially available labeled riboflavin and atp ... | 2015 | 26149960 |
| quaternary organization in a bifunctional prokaryotic fad synthetase: involvement of an arginine at its adenylyltransferase module on the riboflavin kinase activity. | prokaryotic fad synthetases (fadss) are bifunctional enzymes composed of two modules, the c-terminal module with atp:riboflavin kinase (rfk) activity, and the n-terminus with atp:fmn adenylyltransferase (fmnat) activity. the fads from corynebacterium ammoniagenes, cafads, forms transient oligomers during catalysis. these oligomers are stabilized by several interactions between the rfk and fmnat sites from neighboring protomers, which otherwise are separated in the monomeric enzyme. among these i ... | 2015 | 25801930 |
| truncated fad synthetase for direct biocatalytic conversion of riboflavin and analogs to their corresponding flavin mononucleotides. | the preparation of flavin mononucleotide (fmn) and fmn analogs from their corresponding riboflavin precursors is traditionally performed in a two-step procedure. after initial enzymatic conversion of riboflavin to flavin adenine dinucleotide (fad) by a bifunctional fad synthetase, the adenyl moiety of fad is hydrolyzed with snake venom phosphodiesterase to yield fmn. to simplify the protocol, we have engineered the fad synthetase from corynebacterium ammoniagenes by deleting its n-terminal adeny ... | 2013 | 24170887 |
| key residues at the riboflavin kinase catalytic site of the bifunctional riboflavin kinase/fmn adenylyltransferase from corynebacterium ammoniagenes. | many known prokaryotic organisms depend on a single bifunctional enzyme, encoded by the ribc of ribf gene and named fad synthetase (fads), to convert riboflavin (rf), first into fmn and then into fad. the reaction occurs through the sequential action of two activities present on a single polypeptide chain where the n-terminus is responsible for the atp:fmn adenylyltransferase (fmnat) activity and the c-terminus for the atp: riboflavin kinase (rfk) activity. sequence and structural analysis sugge ... | 2013 | 22892871 |
| x-ray reduction correlates with soaking accessibility as judged from four non-crystallographically related diiron sites. | x-ray crystallography is extensively used to determine the atomic structure of proteins and their cofactors. though a commonly overlooked problem, it has been shown that structural damage to a redox active metal site may precede loss of diffractivity by more than an order of magnitude in x-ray dose. therefore the risk of misassigning redox states is great. adequate treatment and consideration of this issue is of paramount importance in metalloprotein science, from experimental design to interpre ... | 2012 | 22859273 |
| effect of osmotic strength on 5'-inosinic acid fermentation in mutants of corynebacterium ammoniagenes. | the effect of osmotic strength on 5'-inosinic acid (imp) fermentation was examined with a mutant, corynebacterium ammoniagenes ky10895. the growth of ky10895 was inhibited by increased osmotic strength in the medium, but the specific imp production (imp produced/cell density) was promoted. the concentration of l-proline increased greatly under osmotic stress. mutants resistant to growth inhibition by osmotic strength were derived from ky10895. strain h-4415 had the highest imp productivity. the ... | 1992 | 27286204 |
| homologous expression of the nrdf gene of corynebacterium ammoniagenes strain atcc 6872 generates a manganese-metallocofactor (r2f) and a stable tyrosyl radical (y˙) involved in ribonucleotide reduction. | ribonucleotide reduction, the unique step in the pathway to dna synthesis, is catalyzed by enzymes via radical-dependent redox chemistry involving an array of diverse metallocofactors. the nucleotide reduction gene (nrdf) encoding the metallocofactor containing small subunit (r2f) of the corynebacterium ammoniagenes ribonucleotide reductase was reintroduced into strain c. ammoniagenes atcc 6872. efficient homologous expression from plasmid poca2 using the tac-promotor enabled purification of r2f ... | 2010 | 20977673 |
| model based optimization of the fed-batch production of a highly active transglutaminase variant in escherichia coli. | a process for the production of a thermostable variant of a microbial transglutaminase was developed. the transglutaminase variant produced, carried a single amino acid exchange (serine replaced by proline at position 2) and showed a nearly doubled specific activity of 46.1 umg(-1) compared to the wild-type enzyme. based on a model based optimization strategy, intracellular soluble production in escherichia coli was optimized. after parameter identification and only two fed-batch cultivations, a ... | 2010 | 21168505 |
| deoxycytidine production by metabolically engineered corynebacterium ammoniagenes. | corynebacterium ammoniagenes n424 was metabolically modified to isolate overproducers of deoxycytidine. inosine auxotrophy (ino) was initially introduced to prevent the flow of prpp (phosphoribosyl pyrophosphate) into the purine biosynthetic pathway by random mutagenesis using n-methyl-n'-nitro-n-nitrosoguanidine. following that, mutants possessing hydroxyurea resistance (hu(r)) were isolated to increase the activity of ribonucleoside diphosphate reductase, which catalyzes the reduction of ribon ... | 2011 | 21369979 |
| efficient multi-enzyme-catalyzed cdp-choline production driven by an atp donor module. | cytidine diphosphate choline (cdp-choline) has been applied for treating acute craniocerebral injury and allowing recovery of consciousness after brain surgery. in this study, an acetate kinase (ack)/acetyl phosphate system was used to supply atp and combined with escherichia coli-overexpressed cmp kinase (cmk), ndp kinase (ndk), choline phosphate cytidylyltransferase (cct), and choline kinase (cki) to produce cdp-choline from cmp and choline chloride. within 1 h, 49 mm cdp-choline was produced, ... | 2017 | 27738720 |
| production of long chain alcohols and alkanes upon coexpression of an acyl-acp reductase and aldehyde-deformylating oxygenase with a bacterial type-i fatty acid synthase in e. coli. | microbial long chain alcohols and alkanes are renewable biofuels that could one day replace petroleum-derived fuels. here we report a novel pathway for high efficiency production of these products in escherichia coli strain bl21(de3). we first identified the acyl-acp reductase/aldehyde deformylase combinations with the highest activity in this strain. next, we used catalase coexpression to remove toxic byproducts and increase the overall titer. finally, by introducing the type-i fatty acid synth ... | 2015 | 26135500 |
| n-acetylcysteine inhibits growth, adhesion and biofilm formation of gram-positive skin pathogens. | n-acetylcysteine (nac) is a non-antibiotic drug with antimicrobial properties against biofilm phenotypes of gram-positive and gram-negative bacteria. our aim was to assess the effects of nac on the growth of gram-positive human skin and mucous membrane pathogens in the planktonic and biofilm phases. the minimum inhibitory concentrations (mics) of nac against enterococcus faecalis, corynebacterium ammoniagenes, mycobacterium smegmatis, propionibacterium acnes, staphylococcus aureus, s. epidermidi ... | 2017 | 28237766 |
| differences in microbiome in rat models of cardiovascular disease. | recent studies have underscored the important role the gut metagenome in various human diseases, including diabetes and obesity. hypertension is a major risk factor for cardiovascular disease, stroke, and heart and kidney failure, and affects approximately 25% of the world's adult population. the cause of essential hypertension remains unknown. patients given antibiotics show blood pressure changes and transfer of gut bacteria from hypertensive to normal wky rats resulted in the latter developin ... | 2017 | 28876684 |
| kinetics and thermodynamics of the protein-ligand interactions in the riboflavin kinase activity of the fad synthetase from corynebacterium ammoniagenes. | enzymes known as bifunctional and bimodular prokaryotic type-i fad synthetase (fads) exhibit atp:riboflavin kinase (rfk) and fmn:atp adenylyltransferase (fmnat) activities in their c-terminal and n-terminal modules, respectively, and produce flavin mononucleotide (fmn) and flavin adenine dinucleotide (fad). these act as cofactors of a plethora of flavoproteins in all organisms. therefore, regulation of their production maintains the cellular flavoproteome homeostasis. here, we focus on regulatio ... | 2017 | 28779158 |
| orthogonal fatty acid biosynthetic pathway improves fatty acid ethyl ester production in saccharomyces cerevisiae. | fatty acid ethyl esters (faees) are a form of biodiesel that can be microbially produced via a transesterification reaction of fatty acids with ethanol. the titer of microbially produced faees can be greatly reduced by unbalanced metabolism and an insufficient supply of fatty acids, resulting in a commercially inviable process. here, we report on a pathway engineering strategy in saccharomyces cerevisiae for enhancing the titer of microbially produced faees by providing the cells with an orthogo ... | 2015 | 25594225 |
| role of key residues at the flavin mononucleotide (fmn):adenylyltransferase catalytic site of the bifunctional riboflavin kinase/flavin adenine dinucleotide (fad) synthetase from corynebacterium ammoniagenes. | in mammals and in yeast the conversion of riboflavin (rf) into flavin mononucleotide (fmn) and flavin adenine dinucleotide (fad) is catalysed by the sequential action of two enzymes: an atp:riboflavin kinase (rfk) and an atp:fmn adenylyltransferase (fmnat). however, most prokaryotes depend on a single bifunctional enzyme, fad synthetase (fads), which folds into two modules: the c-terminal associated with rfk activity and the n-terminal associated with fmnat activity. sequence and structural anal ... | 2012 | 23203077 |
| influence of oxidative and nitrosative stress on accumulation of diphosphate intermediates of the non-mevalonate pathway of isoprenoid biosynthesis in corynebacteria and mycobacteria. | artificial generation of oxygen superoxide radicals in actively growing cultures of mycobacterium tuberculosis, myc. smegmatis, and corynebacterium ammoniagenes is followed by accumulation in the bacterial cells of substantial amounts of 2-c-methyl-d-erythritol-2,4-cyclodiphosphate (mecdp) - an intermediate of the non-mevalonate pathway of isoprenoid biosynthesis (mep) - most possibly due to the interaction of the oxygen radicals with the 4fe-4s group in the active center and inhibition of the e ... | 2012 | 22809155 |