Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| characterization of the plasmid pmb1 from bifidobacterium longum and its use for shuttle vector construction. | the nucleotide sequence of the 1847-bp bifidobacterium longum b2577 cryptic plasmid pmb1 was determined. the plasmid had a g+c content of 62.0%, and contained two open reading frames, orf1 and orf2, likely arranged in an operon. the proteins encoded by orf1 and orf2 show the highest degree of similarity with similarly arranged peptide sequences translated from corynebacterium glutamicum pxz10142 and mycobacterium fortuitum pal5000 plasmids. recombinant plasmids containing the pmb1 replicon were ... | 1996 | 8761732 |
| mutations in the corynebacterium glutamicum proline biosynthetic pathway: a natural bypass of th proa step. | two chromosomal loci containing the corynebacterium glutamicum atcc 17965 prob and proc genes were isolated by complementation of escherichia coli prob and proc auxotrophic mutants. together with a proa gene described earlier, these new genes describe the major c. glutamicum proline biosynthetic pathway. the prob and proa genes, closely linked in most bacteria, are in c. glutamicum separated by a 304-amino-acid open reading frame (unk) whose predicted sequence resembles that of the 2-hydroxy aci ... | 1996 | 8755867 |
| isolation, characterization, and expression of the corynebacterium glutamicum betp gene, encoding the transport system for the compatible solute glycine betaine. | corynebacterium glutamicum accumulates glycine betaine under conditions of high osmolarity. previous work revealed the existence of a high-affinity glycine betaine permease which is osmotically regulated. in the present study, the corresponding gene was cloned. the betp gene, encoding the glycine betaine uptake carrier, was isolated by heterologous complementation of mutant strain escherichia coli mkh13. from sequence analysis it is predicted to encode a protein of 595 amino acids. this protein ... | 1996 | 8752342 |
| molecular cloning, sequence analysis, and functional characterization of the lipopolysaccharide biosynthetic gene kdta encoding 3-deoxy-alpha-d-manno-octulosonic acid transferase of chlamydia pneumoniae strain tw-183. | the gene kdta of chlamydia pneumoniae strain tw-183, encoding the enzyme 3-deoxy-alpha-d-manno-octulosonic acid (kdo) transferase of lipopolysaccharide biosynthesis, was cloned and sequenced. a single open reading frame of 1314 bp was identified, the deduced amino acid sequence of which revealed 69% similarity and 43% identity with kdta of chlamydia trachomatis and chlamydia psittaci. the gene was expressed in the gram-positive host corynebacterium glutamicum and the primary gene product was cha ... | 1995 | 8748024 |
| promoters from corynebacterium glutamicum: cloning, molecular analysis and search for a consensus motif. | relatively limited information about promoter structures in corynebacterium glutamicum has been available until now. with the aim of isolating and characterizing such transcription initiation signals, random sau3a fragments of c. glutamicum chromosomal dna and of the corynebacterial phage phi ga1 were cloned into the promoter probe vector pekplcm and selected for promoter activity by chloramphenicol resistance of transformed c. glutamicum cells. the nucleotide sequence of ten chromosomal and thr ... | 1996 | 8704969 |
| c3-carboxylation as an anaplerotic reaction in phosphoenolpyruvate carboxylase-deficient corynebacterium glutamicum. | phosphoenolpyruvate carboxylase (pepcx) has recently been found to be dispensable as an anaplerotic enzyme for growth and lysine production of corynebacterium glutamicum. to clarify the role of the glyoxylate cycle as a possible alternative anaplerotic sequence, defined pepcx- and isocitrate-lyase (icl)-negative double mutants of c. glutamicum wild-type and of the l-lysine-producing strain mh20-22b were constructed by disruption of the respective genes. analysis of these mutants revealed that th ... | 1996 | 8661932 |
| construction of l-lysine-, l-threonine-, and l-isoleucine-overproducing strains of corynebacterium glutamicum. | the gram-negative bacterium corynebacterium glutamicum is used for the industrial production of amino acids, for example, of l-glutamate and l-lysine. by cloning and expressing the various genes of the l-lysine pathway in c. glutamicum, we would demonstrate that an increase of the flux of l-aspartate semialdehyde to l-lysine could be obtained in strains with increased dihydrodipicolinate synthase activity. recently we detected that in c. glutamicum two pathways exist for synthesis of d,l-diamino ... | 1996 | 8659901 |
| transport mutants and transport genes of corynebacterium glutamicum. | 1996 | 8659896 | |
| functional and genetic characterization of the (methyl)ammonium uptake carrier of corynebacterium glutamicum. | under nitrogen starvation conditions, corynebacterium glutamicum was found to take up methylammonium at a rate of 20 +/- 5 nmol.min-1.(mg dry weight)-1. the specific activity of this uptake was 10-fold lower when growing the cells under sufficient nitrogen supply, indicating a tight regulation on the expression level. the methylammonium uptake showed michaelis-menten kinetics with an km of 44 +/- 7 microm and was completely inhibited by the addition of 10 microm ammonium. this finding and the fa ... | 1996 | 8621394 |
| cloning and characterization of an is-like element present in the genome of brevibacterium lactofermentum atcc 13869. | a repetitive dna element of the gram+ brevibacterium lactofermentum (bl), cloned by a modification of the subtractive hybridization method, contained a 1.4-kb is-like element, is13869, which included an open reading frame (orf) inside a perfect 26-bp terminal inverted repeat (tir). an 8-bp direct repeat (dr) was found outside each tir. the orf encoded a deduced protein of 436 amino acids (49 380 da) with extensive similarity to other known transposases of insertion elements of mycobacterium smeg ... | 1996 | 8621097 |
| genetic characterization of site-specific integration functions of phi aau2 infecting "arthrobacter aureus" c70. | all the essential genetic determinants for site-specific integration of corynephage phi aau2 are contained within a 1,756-bp dna fragment, carried on the integrative plasmid p5510, and are shown to be functional in escherichia coli. one open reading frame, orf4, encoding a protein of 266 amino acids was shown to represent the phi aau2 integrase. the nucleotide sequence of the phi aau2 attachment site, attp, and the attb, attl, and attr sequences in the host "arthrobacter aureus" c70 were determi ... | 1996 | 8606175 |
| cloning of m-fluorophenylalanine-resistant gene and mutational analysis of feedback-resistant prephenate dehydratase from corynebacterium glutamicum. | corynebacterium glutamicum was mutated by nitrosoguanidine and five m-fluorophenylalanine (mfp)-resistant mutants were isolated. the mutants were resistant to phenylalanine-mediated feedback inhibition of the prephenate dehydratase activity. cloning and characterization of the mfp-resistant gene revealed that mutant prephenate dehydratase, encoded by the phe a gene, confers the mfp-resistant phenotype upon c. glutamicum. to determine the amino acid residues to which variation may result in the f ... | 1996 | 8605023 |
| genes and enzymes of the acetyl cycle of arginine biosynthesis in corynebacterium glutamicum: enzyme evolution in the early steps of the arginine pathway. | a cluster of arginine biosynthetic genes of corynebacterium glutamicum atcc 13032, comprising argj, argb and argd as well as part of argc and argf, has been cloned by heterologous complementation of an escherichia coli arge mutant. the gene order has been established as argcjbdf by sequencing the entire 4.4 kb cloned dna fragment. the c. glutamicum argb gene can be transcribed in e. coli cells from an internal promoter located in the coding part of the preceding argj gene, whereas transcription ... | 1996 | 8581175 |
| the corynebacterium xerosis composite transposon tn5432 consists of two identical insertion sequences, designated is1249, flanking the erythromycin resistance gene ermcx. | analysis of the 50-kb r-plasmid ptp10 from the clinical isolate corynebacterium xerosis m82b revealed that the erythromycin resistance gene, ermcx, is located on a 4524-bp composite transposable element, tn5432. the ends of tn5432 are identical, direct repeats of an insertion sequence, designated is1249, encoding a putative transposase of the is256 family. is1249 consists of 1385 bp with 45/42 imperfect terminal inverted repeats. the nucleotide sequence of the 1754-bp tn5432 central region is 99 ... | 1995 | 8559800 |
| multiple sigma factor genes in brevibacterium lactofermentum: characterization of siga and sigb. | four rpod hybridizing signals have been identified in the chromosome of brevibacterium lactofermentum. two rpod-like genes, siga and sigb, have been cloned and sequenced, and they encode principal sigma factors of the rna polymerase. the deduced amino acid sequences of siga and sigb showed very high similarities to those of mycobacterium smegmatis mysa and mysb proteins, respectively, and also to those of hrdb proteins from different streptomyces species. siga and sigb maintain the conserved mot ... | 1996 | 8550480 |
| mutations in the trpd gene of corynebacterium glutamicum confer 5-methyltryptophan resistance by encoding a feedback-resistant anthranilate phosphoribosyltransferase. | the trpd gene from tryptophan-hyperproducing corynebacterium glutamicum atcc 21850 was isolated on the basis of its ability to confer resistance to 5-methyltryptophan on wild-type c. glutamicum as019. comparative sequence analysis of the genes from the wild-type as019 and atcc 21850 trpd genes revealed two amino acid substitutions at the protein level. further analysis demonstrated that the trpd gene product from atcc 21850, anthranilate phosphoribosyltransferase, was more resistant to feedback ... | 1995 | 8534114 |
| prophage distribution in coryneform bacteria. | four temperate bacteriophages of corynebacteria were isolated after uv induction. phages phi 304l and phi 304s were both induced from corynebacterium glutamicum atcc 13058, atcc 21488, atcc 21649 and atcc 21650 strains, and have no known sensitive host. phages phi 15 and phi 16 were both induced from atcc 14020 and atcc 21792. phage phi 15 formed turbid plaques on corynebacterium sp. atcc 21857 and on c. glutamicum atcc 13058, atcc 21488, atcc 21649 and atcc 21650. phage phi 16 produced turbid p ... | 1995 | 8525066 |
| multicopy suppression by asd gene and osmotic stress-dependent complementation by heterologous proa in proa mutants. | auxotrophic proa mutants of escherichia coli were complemented by two different classes of corynebacterium glutamicum genes. one of these was the asd gene. the e. coli asd gene also complements the same proa alleles. complementation of proa by the asd+ gene requires a high asd dosage and the prob and the proc gene products. the reciprocal complementation pattern (asd by the proa+ gene) was not observed. this complementation appears to be due to multicopy suppression by a proline biosynthetic gen ... | 1995 | 8522535 |
| purification, characterization, and lytic activity against naegleria fowleri of two amoebicins produced by bacillus licheniformis a12. | bacillus licheniformis a12 produces two amoebolytic substances (amoebicins a12-a and a12-b) in liquid media during sporulation. both substances have been purified and characterized. they are heat- and protease-resistant peptides containing aspartic acid, glutamic acid, serine, proline, and tyrosine in a molar ratio of 5:2:2:2:2. no fatty acids or carbohydrates have been detected. their molecular weight is 1,430. purified amoebicins a12-a and a12-b exhibit amoebolytic action against naegleria fow ... | 1993 | 8517742 |
| flux partitioning in the split pathway of lysine synthesis in corynebacterium glutamicum. quantification by 13c- and 1h-nmr spectroscopy. | the gram-positive corynebacterium glutamicum has the potential to synthesize l-lysine via a split pathway, where amino-ketopimelate is converted to the ultimate lysine precursor diaminopimelate either by reactions involving succinylated intermediates, or by one single reaction catalysed by d-diaminopimelate dehydrogenase. to quantify the flux distribution via both pathways, 13c-enriched glucose was used and specific enrichments in lysine and in pyruvate-derived metabolites were determined by 13c ... | 1993 | 8504824 |
| corynebacterium glutamicum arginyl-trna synthetase. | 1993 | 8497194 | |
| a cluster of three genes (dapa, orf2, and dapb) of brevibacterium lactofermentum encodes dihydrodipicolinate synthase, dihydrodipicolinate reductase, and a third polypeptide of unknown function. | the dapa and dapb genes, encoding, respectively, dihydrodipicolinate synthase and dihydrodipicolinate reductase, the two first enzymes of the lysine branch of the aspartic amino acid family, were cloned from the dna of the amino acid-producing bacterium brevibacterium lactofermentum. the two genes were clustered in a 3.5-kb sau3ai-bamhi fragment but were separated by an open reading frame of 750 nucleotides. the protein encoded by this open reading frame had little similarity to any protein in t ... | 1993 | 8478336 |
| characterization of the arcd arginine:ornithine exchanger of pseudomonas aeruginosa. localization in the cytoplasmic membrane and a topological model. | the arcdabc operon of pseudomonas aeruginosa encodes the enzymes of the arginine deiminase pathway and is induced by oxygen limitation. the arcd gene specifies a 53-kda protein with arginine: ornithine exchange activity. the arcd protein of p. aeruginosa, like the lysi lysine transporter of corynebacterium glutamicum, has 13 hydrophobic regions which could span the cytoplasmic membrane. fusion of a caa (colicin a) epitope to the n-terminal part of arcd permitted the localization, by immunoblotti ... | 1993 | 8449902 |
| characterization of the cspb gene encoding ps2, an ordered surface-layer protein in corynebacterium glutamicum. | ps2 is one of two major proteins detected in the culture media of various corynebacterium glutamicum strains. the coding and promoter regions of the cspb gene encoding ps2 were cloned in lambda gt11 using polyclonal antibodies raised against ps2 for screening. expression of the cspb gene in escherichia coli led to the production of a major anti-ps2 labelled peptide of 63,000 da, corresponding presumably to the mature form of ps2. it was detected in the cytoplasm, periplasm and surrounding medium ... | 1993 | 8412676 |
| the dna sequence and minimal replicon of the corynebacterium glutamicum plasmid psr1: evidence of a common ancestry with plasmids from c. diphtheriae. | the complete nucleotide sequence of psr1, a 3 kb multicopy cryptic plasmid from corynebacterium glutamicum atcc 19223 has been determined. psr1 is unrelated to the 4.4 kb brevibacterium lactofermentum plasmid pbl1 and shows no dna sequence conservation with plasmids from staphylococcus. transposon insertion and deletion mutants located the minimal replicon to within a 2.1 kb ncoi-bcli restriction fragment. this region contains a single large open reading frame, orf2, flanked at the 5' end by a s ... | 1993 | 8409918 |
| numerical analysis of fatty and mycolic acid profiles of corynebacterium urealyticum and other related corynebacteria. | the fatty and mycolic acid profiles of 52 strains of clinical origin belonging to corynebacterium urealyticum were subjected to numerical analysis along with those of representative members of corynebacterium ammoniagenes, corynebacterium bovis, corynebacterium glutamicum, corynebacterium jèikeium, corynebacterium minutissimum, corynebacterium pseudodiphtheriticum, corynebacterium pseudotuberculosis, corynebacterium xerosis, corynebacterium renale, corynebacterium cystitidis, "corynebacterium ul ... | 1993 | 8397966 |
| evolutionary comparisons of three enzymes of the threonine biosynthetic pathway among several microbial species. | as an approach in the study of the evolution of threonine biosynthetic pathways throughout various organisms, the sequences of three enzymes, namely homoserine dehydrogenase, homoserine kinase and threonine synthase, originating from six organisms, namely escherichia coli, bacillus subtilis, corynebacterium glutamicum, brevibacterium lactofermentum, pseudomonas aeruginosa and saccharomyces cerevisiae, were compared. as a general trend all three enzymatic activities were carried out by proteins s ... | 1993 | 8395899 |
| role of the protonmotive force and of the state of the lipids in the in vivo protein secretion in corynebacterium glutamicum, a gram-positive bacterium. | ps1 is a protein translocated across the cytoplasmic membrane of corynebacterium glutamicum, a gram-positive bacterium. western blots of whole cell extracts showed the presence of two bands associated with the mature and the precursor forms. addition of chloramphenicol led to the disappearance of the precursor form while dissipation of the protonmotive force (delta microh) prior to the addition of chloramphenicol prevented the maturation of the precursor. dissipation of delta microh prior to a p ... | 1993 | 8382958 |
| isoleucine synthesis in corynebacterium glutamicum: molecular analysis of the ilvb-ilvn-ilvc operon. | acetohydroxy acid synthase (ahas) and isomeroreductase (ir) catalyze subsequent reactions in the flux of metabolites towards isoleucine, valine, leucine, and pantothenate. a 4,705-bp dna fragment from corynebacterium glutamicum known to code for ahas and ir was sequenced and analyzed by northern (rna blot) analysis. as in other bacteria, the ahas of this gram-positive organism is encoded by two genes, ilvb and ilvn. gene disruption verified that these genes encode the single ahas activity in c. ... | 1993 | 8366043 |
| codon preference in corynebacteria. | the codon usage (cu) of 34 genes from the closely related species, brevibacterium lactofermentum and corynebacterium glutamicum (blcg), was analysed and compared with that of 23 genes from other brevibacterium and corynebacterium species. the g+c content of the blcg genes ranged from 50 to 62%. a wider range was found in other corynebacterial genes (25-71%). the g+c contents of non-coding regions in glutamic acid bacteria are lower than those of the coding regions and both values are lower than ... | 1993 | 8244028 |
| lactose permease of escherichia coli catalyzes active beta-galactoside transport in a gram-positive bacterium. | the following several lines of evidence demonstrate that lactose permease (lacy) of escherichia coli is assembled into the cytoplasmic membrane of gram-positive corynebacterium glutamicum, expressing the lacy gene, as a functional carrier protein. (i) lacy was detected immunologically in the cytoplasmic membrane fraction of the heterologous host. (ii) recombinant c. glutamicum cells bearing the lacy gene displayed an increased influx of o-nitrophenyl-beta-d-galactopyranoside, which was inhibited ... | 1993 | 8226697 |
| a gene encoding arginyl-trna synthetase is located in the upstream region of the lysa gene in brevibacterium lactofermentum: regulation of args-lysa cluster expression by arginine. | the brevibacterium lactofermentum args gene, which encodes an arginyl-trna synthetase, was identified in the upstream region of the lysa gene. the cloned gene was sequenced; it encodes a 550-amino-acid protein with an m(r) of 59,797. the deduced amino acid sequence showed 28% identical and 49% similar residues when compared with the sequence of the escherichia coli arginyl-trna synthetase. the b. lactofermentum enzyme showed the highly conserved motifs of class i aminoacyl-trna synthetases. expr ... | 1993 | 8226683 |
| in vivo modulating effects of bacterial peptidoglycans on pha-induced responses of porcine pbl and splenocytes. | the modulating effect of brevibacterium divaricatum cell wall derivatives, i.e. peptidoglycan monomer (pgm) and peptidoglycan polymer (pgp) on phytohemagglutinin (pha)-induced responses of peripheral blood lymphocytes (pbl) and spleen lymphocytes (spl) from neonatal pigs farrowed to gilts or sows was tested. both, pbl from progeny of sows and spl from progeny of gilts responded significantly lower (p < 0.01) when pgm (14 mg/kg) was given by intraperitoneal (ip) route at day 0 and day 7 after far ... | 1993 | 8225389 |
| cloning and sequence analysis of the meso-diaminopimelate decarboxylase gene from bacillus methanolicus mga3 and comparison to other decarboxylase genes. | the lysa gene of bacillus methanolicus mga3 was cloned by complementation of an auxotrophic escherichia coli lysa22 mutant with a genomic library of b. methanolicus mga3 chromosomal dna. subcloning localized the b. methanolicus mga3 lysa gene into a 2.3-kb smai-ssti fragment. sequence analysis of the 2.3-kb fragment indicated an open reading frame encoding a protein of 48,223 da, which was similar to the meso-diaminopimelate (dap) decarboxylase amino acid sequences of bacillus subtilis (62%) and ... | 1993 | 8215365 |
| presence of mrr- and mcr-like restriction systems in coryneform bacteria. | efficient transformation of brevibacterium flavum mj233c and corynebacterium glutamicum atcc 31831 (up to 5.0 x 10(7) transformants/microgram dna) depends on the source of plasmid dna. the transformation efficiencies of b. flavum mj233c and c. glutamicum atcc 31831 increased nearly 10(3)-fold when plasmid dna was isolated from the recipient strain itself or from a damdcm escherichia coli mutant, as compared with dna passed through a modification-proficient e. coli strain. these results suggest t ... | 1993 | 8210675 |
| characterization of the isocitrate lyase gene from corynebacterium glutamicum and biochemical analysis of the enzyme. | isocitrate lyase is a key enzyme in the glyoxylate cycle and is essential as an anaplerotic enzyme for growth on acetate as a carbon source. it is assumed to be of major importance in carbon flux control in the amino acid-producing organism corynebacterium glutamicum. in crude extracts of c. glutamicum, the specific activities of isocitrate lyase were found to be 0.01 u/mg of protein after growth on glucose and 2.8 u/mg of protein after growth on acetate, indicating tight regulation. the isocitr ... | 1994 | 8206824 |
| isolation and characterization of is31831, a transposable element from corynebacterium glutamicum. | a transposable element from a coryneform bacterium, corynebacterium glutamicum atcc 31831 was isolated and characterized. the element is31831 is a 1453 bp insertion sequence with 24 bp imperfect terminal inverted repeats. it contains one open reading frame highly homologous at the amino acid level to the transposase of is1096 from mycobacterium smegmatis. both is31831 and is1096 exhibit several common characteristics suggesting that they constitute a new family of insertion sequences. is31831 wa ... | 1994 | 8196545 |
| characterization of a region of plasmid pbl1 of brevibacterium lactofermentum involved in replication via the rolling circle model. | the minimal region for autonomous replication of pbl1, a 4.5-kb cryptic plasmid of brevibacterium lactofermentum atcc 13869 that has been used to construct a variety of corynebacterium vectors, was shown to be contained on a 1.8-kb hindii-sphi dna fragment. this region contains two open reading frames (orfs) (orf1 and orf5) which are essential for pbl1 replication in b. lactofermentum. accumulation of single-strand intermediates in some of the constructions indicates that plasmid pbl1 replicates ... | 1994 | 8195068 |
| analysis of the biotin biosynthesis pathway in coryneform bacteria: cloning and sequencing of the biob gene from brevibacterium flavum. | the biotin biosynthetic pathway of three coryneform bacteria, brevibacterium flavum, brevibacterium lactofermentum, and corynebacterium glutamicum were analysed by cross-feeding experiments using several escherichia coli biotin-requiring mutants. the three strains of coryneform bacteria tested were able to convert 7-keto-8-aminopelargonic acid to biotin, through a biotin synthetic pathway identical to that from e. coli. the biotin biosynthetic gene, biob, of b. flavum was cloned by phenotypic co ... | 1993 | 8173080 |
| genomic organization of the biotin biosynthetic genes of coryneform bacteria: cloning and sequencing of the bioa-biod genes from brevibacterium flavum. | three coryneform bacteria, brevibacterium flavum, brevibacterium lactofermentum and corynebacterium glutamicum have been shown to be able to convert 7-keto-8-aminopelargonic acid to biotin through a biotin synthetic pathway identical to that from escherichia coli (hatakeyama et al., dna sequence, in press, 1993). we report in this paper the cloning and sequencing of the biotin biosynthetic genes encoding the 7,8-diaminopelargonic acid aminotransferase (bioa) and the dethiobiotin synthetase (biod ... | 1993 | 8161820 |
| increased fertility of corynebacterium glutamicum recipients in intergeneric matings with escherichia coli after stress exposure. | corynebacterial recipient cells exposed to heat, organic solvents, ph shifts, or detergents show an increased fertility in subsequent interspecific matings with escherichia coli. this effect is independent of de novo protein biosynthesis and seems to be due to a direct inactivation of a restriction system active against foreign dna that enters the cell by incp-mediated conjugation. | 1994 | 8135527 |
| leucine synthesis in corynebacterium glutamicum: enzyme activities, structure of leua, and effect of leua inactivation on lysine synthesis. | enzymes and genes of the isopropylmalate pathway leading to leucine in corynebacterium glutamicum were studied, and assays were performed to unravel their connection to lysine oversynthesis. the first enzyme of the pathway is inhibited by leucine (ki = 0.4 mm), and all three enzyme activities of the isopropylmalate pathway are reduced upon addition of this amino acid to the growth medium. three different dna fragments were cloned, each resulting in an oversynthesis of one of the three enzymes. t ... | 1994 | 8117072 |
| the cloning and nucleotide sequence of a corynebacterium glutamicum 3-deoxy-d-arabinoheptulosonate-7-phosphate synthase gene. | the aro gene of corynebacterium glutamicum ccrc 18310 encoding 3-deoxy-d-arabinoheptulosonate-7-phosphate (dahp) synthase was isolated by complementation of a dahp synthase-deficient mutant of escherichia coli ab3257. the specific activity of dahp synthase was increased four-fold in a c. glutamicum strain harboring the cloned aro gene. the complete nucleotide sequence of the aro gene and its 5' and 3' flanking regions has been determined. the sequence contained an open reading frame of 368 codon ... | 1993 | 8097175 |
| direct evidence for a constitutive internal promoter in the tryptophan operon of corynebacterium glutamicum. | insertional inactivation of the trpe gene in corynebacterium glutamicum as019 blocked expression of the trp operon from the primary promoter and resulted in tryptophan auxotrophy. the presence of indole, the substrate for the terminal trp pathway enzyme tryptophan synthase, reversed this auxotrophy thereby providing evidence for the existence of an internal promoter independently expressing the tryptophan synthase genes (trpb and trpa). the toxic tryptophan analogue 6-fluorotryptophan failed to ... | 1994 | 8093062 |
| molecular aspects of lysine, threonine, and isoleucine biosynthesis in corynebacterium glutamicum. | the gram-positive bacterium corynebacterium glutamicum is used for the industrial production of amino acids, e.g. of l-glutamate and l-lysine. in the last ten years genetic engineering methods were developed for c. glutamicum and consequently, recombinant dna technology was employed to study the biosynthetic pathways and to improve the amino acid productivity by manipulation of enzymatic, transport and regulatory functions of this bacterium. the present review summarizes the current knowledge on ... | 1993 | 8092856 |
| structural and functional analysis of pyruvate kinase from corynebacterium glutamicum. | pyruvate kinase activity is an important element in the flux control of the intermediate metabolism. the purified enzyme from corynebacterium glutamicum demonstrated a marked sigmoidal dependence of the initial rate on the phosphoenolpyruvate concentration. in the presence of the negative allosteric effector atp, the phosphoenolpyruvate concentration at the half-maximum rate (s0.5) increased from 1.2 to 2.8 mm, and cooperation, as expressed by the hill coefficient, increased from 2.0 to 3.2. amp ... | 1994 | 8074528 |
| cloning of the pyruvate kinase gene (pyk) of corynebacterium glutamicum and site-specific inactivation of pyk in a lysine-producing corynebacterium lactofermentum strain. | the pyruvate kinase gene pyk from corynebacterium glutamicum was cloned by applying a combination of pcr, site-specific mutagenesis, and complementation. a 126-bp dna fragment central to the c. glutamicum pyk gene was amplified from genomic dna by pcr with degenerate oligonucleotides as primers. the cloned dna fragment was used to inactivate the pyk gene in c. glutamicum by marker rescue mutagenesis via homologous recombination. the c. glutamicum pyk mutant obtained was unable to grow on minimal ... | 1994 | 8074527 |
| analysis and expression of the thrc gene of brevibacterium lactofermentum and characterization of the encoded threonine synthase. | the thrc gene of brevibacterium lactofermentum was cloned by complementation of escherichia coli thrc auxotrophs. the gene was located by deletion mapping and complementation analysis in a 2.9-kb sau3ai-hindiii fragment of the genome. this fragment also complemented a b. lactofermentum ul1035 threonine auxotroph that was deficient in threonine synthase. a 1,892-bp dna fragment of this region was sequenced; this fragment contained a 1,446-bp open reading frame that encoded a 481-amino-acid protei ... | 1994 | 8074505 |
| determination of nucleotide sequence of corynebacterium plasmid pxz10145. | with abi370a autosequencer, the total nucleotide sequence of plasmid pxz10145 from corynebacterium glutamicum 1014-6t has been determined using the dideoxy chain termination method. the plasmid contain 4887 base pairs (bp). computer-aided-analysis of the sequence showed the location and number of restriction enzyme cutting sites and revealed eight open reading frames (orf) on the plasmid. the two sites on the plasmid pxz10145, where deletion occurred to result in plasmid pnat65 were confirmed. a ... | 1993 | 8049348 |
| small mobilizable multi-purpose cloning vectors derived from the escherichia coli plasmids pk18 and pk19: selection of defined deletions in the chromosome of corynebacterium glutamicum. | here we describe small mobilizable vectors based on the escherichia coli plasmids pk18 and pk19. we combined the useful properties of the pk plasmids (e.g., multiple cloning site, lacz alpha fragment, sequencing with m13 primers) with the broad-host-range transfer machinery of plasmid rp4 and a modified sacb gene from bacillus subtilis. the new pk derivatives can be transferred by rp4-mediated conjugation into a wide range of gram- and gram+ bacteria, and should facilitate gene disruption and al ... | 1994 | 8045426 |
| nucleotide sequence of the gene encoding the corynebacterium glutamicum mannose enzyme ii and analyses of the deduced protein sequence. | the complete nucleotide sequence of the gene encoding the corynebacterium glutamicum mannose enzyme ii (eiiman) was determined. the gene consisted of 2052 base pairs encoding a protein of 683 amino acid residues; the molecular mass of the protein subunit was calculated to be 72570 da. the n-terminal hydrophilic domain of eiiman showed 39.7% homology with a c-terminal hydrophilic domain of escherichia coli glucose-specific enzyme ii (eiiglc). similar homology was shown between the c-terminal sequ ... | 1994 | 8039653 |
| a sequence from a tryptophan-hyperproducing strain of corynebacterium glutamicum encoding resistance to 5-methyltryptophan. | a cloned dna fragment containing the trp gene cluster from the tryptophan-hyperproducing strain corynebacterium glutamicum atcc21850 was found to increase the resistance of escherichia coli to the tryptophan analogs 5-methyltryptophan and 6-fluorotryptophan. a sequence sufficient to mediate resistance to 5-methyltryptophan in e. coli was mapped to a 582-bp sequence located immediately upstream of the c. glutamicum trp operon. the equivalent fragment from the related wild type strain c. glutamicu ... | 1994 | 8024569 |
| expression of ovine gamma interferon in escherichia coli and corynebacterium glutamicum. | bacteria of two species, escherichia coli and corynebacterium glutamicum, were used as hosts to express recombinant ovine gamma interferon as a fusion protein with glutathione s-transferase. the recombinant gamma interferon produced by both bacteria was biologically active in vitro and was recognized by anti-gamma interferon monoclonal antibodies. e. coli produced large amounts of soluble recombinant protein which could be purified by a simple affinity chromatography method. only a small fractio ... | 1994 | 8017943 |
| metabolic engineering of corynebacterium glutamicum. | 1994 | 8010662 | |
| in situ probing of gram-positive bacteria with high dna g + c content using 23s rrna-targeted oligonucleotides. | 23s-rrna-targeted oligonucleotide probes were designed for the phylogenetic group 'gram-positive bacteria with high g + c content of dna' (gpbhgc). a sequence idiosyncrasy in two adjacent base pairs in the stem of helix 69 in domain iv of the 23s rrna is present in all hitherto analysed strains of gpbhgc. an oligonucleotide probe targeted to this region hybridized only with strains of gpbhgc and was successfully used for in situ monitoring of these cells in activated sludge. another unique featu ... | 1994 | 8000548 |
| pulsed-field gel electrophoresis analysis of the genome of amino acid producing corynebacteria: chromosome sizes and diversity of restriction patterns. | a large number of species of corynebacteria are known to be amino acid producers, including members of the genera corynebacterium and brevibacterium. pulsed-field gel electrophoresis (pfge) of dna fragments obtained by using endonucleases which recognize at-rich hexanucleotide or octanucleotide sequences produces a discrete pattern of bands useful for fingerprinting and physical mapping of the chromosome. using pacl and swal endonucleases the genome of brevibacterium lactofermentum atcc 13869 (g ... | 1994 | 8000547 |
| corynebacterium glutamicum dna is subjected to methylation-restriction in escherichia coli. | efficient electroporation of escherichia coli with plasmid dna isolated from corynebacterium glutamicum depends on the use of mcr-deficient e. coli strains. the transformation frequency increased nearly 800-fold when the mcr-deficient e. coli dh5 alpha mcr was used instead of e. coli dh5 alpha. we used e. coli strains with different mutations in the methyl-specific restriction systems to show that mcrbc-deficiency is sufficient to generate this effect. the results imply that c. glutamicum dna co ... | 1994 | 7988915 |
| characterization of energetically functional inverted membrane vesicles from corynebacterium glutamicum. | we show that inverted membrane vesicles from corynebacterium glutamicum, a gram-positive bacterium, are able to generate and maintain an electrochemical gradient of protons in response to the addition of nadh. this result indicates that the respiratory chain is intact and that the vesicles are reasonably impermeable to protons. these membrane vesicles may be the starting point for in vitro translocation studies of proteins in gram-positive bacteria. | 1994 | 7988700 |
| mechanism of alanine excretion in recombinant strains of zymomonas mobilis. | a thiamine-auxotrophic strain of zymomonas mobilis (cp4thi/pzy73), in which the alad gene of bacillus sphaericus coding for the alanine dehydrogenase was expressed, synthesizes and excretes alanine at high rates after thiamine starvation and in the presence of high external ammonium concentrations. the mechanism of alanine excretion was studied in this recombinant zymomonas mobilis strain. under production conditions the internal alanine concentration reached values of up to 280 mm and excretion ... | 1994 | 7986805 |
| transcriptional analysis and regulatory signals of the hom-thrb cluster of brevibacterium lactofermentum. | two genes, hom (encoding homoserine dehydrogenase) and thrb (encoding homoserine kinase), of the threonine biosynthetic pathway are clustered in the chromosome of brevibacterium lactofermentum in the order 5' hom-thrb 3', separated by only 10 bp. the brevibacterium thrb gene is expressed in escherichia coli, in brevibacterium lactofermentum, and in corynebacterium glutamicum and complements auxotrophs of all three organisms deficient in homoserine kinase, whereas the brevibacterium hom gene did ... | 1994 | 7961509 |
| cloning and characterization of a dna region encoding a stress-sensitive restriction system from corynebacterium glutamicum atcc 13032 and analysis of its role in intergeneric conjugation with escherichia coli. | rp4-mediated transfer of mobilizable plasmids in intergeneric conjugation of escherichia coli donors with corynebacterium glutamicum atcc 13032 is severely affected by a restriction system in the recipient that can be inactivated by a variety of exogenous stress factors. in this study a rapid test procedure based on intergeneric conjugal plasmid transfer that permitted the distinction between restriction-negative and restriction-positive c. glutamicum clones was developed. by using this procedur ... | 1994 | 7961503 |
| quantitative discrimination of carrier-mediated excretion of isoleucine from uptake and diffusion in corynebacterium glutamicum. | the efflux of isoleucine in whole cells of corynebacterium glutamicum was studied. the different amino acid fluxes across the plasma membrane were functionally discriminated into passive diffusion, carrier-mediated excretion, and carrier-mediated uptake. detailed kinetic analysis was made possible by controlled variation of internal isoleucine from low concentrations to 100 mm by feeding with mixtures of isoleucine-containing peptides. isoleucine diffusion was experimentally separated and procee ... | 1994 | 7961449 |
| fungicin m4: a narrow spectrum peptide antibiotic from bacillus licheniformis m-4. | the strain bacillus licheniformis m-4 produces a 3.4 kda hydrophilic peptide with antifungal activity, named fungicin m4. analysis of the purified peptide shows that it contains the amino acids glu (8), arg (5), pro (4), tyr (8), val (3), met (2) and orn (4). its inhibitory spectrum is restricted to microsporum canis cect 2797, mucor mucedo cect 2653, mucor plumbeus ccm 443, sporothrix schenckii cect 2799, bacillus megaterium and corynebacterium glutamicum cect 78. fungicin m4 exerts biocidal ac ... | 1994 | 7928782 |
| isolation of insertion elements from gram-positive brevibacterium, corynebacterium and rhodococcus strains using the bacillus subtilis sacb gene as a positive selection marker. | the sacb gene of bacillus subtilis was successfully applied in various arthrobacter, brevibacterium, corynebacterium and rhodococcus strains for the isolation of transposable elements. three different insertion sequence (is) elements entrapped in sacb were isolated. the is elements is-bl and is-cg isolated from brevibacterium lactofermentum and corynebacterium glutamicum, respectively, were found to be similar in size (1.45 kb) and generated target duplications of 8 bp. their inverted repeats sh ... | 1995 | 7896070 |
| effect of inducible thrb expression on amino acid production in corynebacterium lactofermentum atcc 21799. | amplification of the operon homdr-thrb encoding a feedback-insensitive homoserine dehydrogenase and a wild-type homoserine kinase in a corynebacterium lactofermentum lysine-producing strain resulted in both homoserine and threonine accumulation, with some residual lysine production. a plasmid enabling separate transcriptional control of each gene was constructed to determine the effect of various enzyme activity ratios on metabolite accumulation. by increasing the activity of homoserine kinase r ... | 1995 | 7887627 |
| identification of is1206, a corynebacterium glutamicum is3-related insertion sequence and phylogenetic analysis. | integration of plasmid pcgl320 into a corynebacterium glutamicum atcc21086 derivative led to tandem amplification of the inserted plasmid (labarre et al., 1993). one amplification event was associated with integration of an insertion sequence that we have named is1206. hybridizing sequences were only found in c. glutamicum strains and at various copy numbers. is1206 is 1290 bp long, carries 32 bp imperfect inverted repeats and generates a 3 bp duplication of the target dna upon insertion. is1206 ... | 1994 | 7885235 |
| analysis of different dna fragments of corynebacterium glutamicum complementing dape of escherichia coli. | in corynebacterium glutamicum l-lysine is synthesized simultaneously via the succinylase and dehydrogenase variant of the diaminopimelate pathway. starting from a strain with a disrupted dehydrogenase gene, three different-sized dna fragments were isolated which complemented defective escherichia coli mutants in the succinylase pathway. enzyme studies revealed that in one case the dehydrogenase gene had apparently been reconstituted in the heterologous host. the two other fragments resulted in d ... | 1994 | 7881553 |
| characterization and sequence analysis of the f2 promoter from corynephage bfk20. | f2 promoter from corynephage bfk20 was isolated and characterized. it was functional in escherichia coli and corynebacterium glutamicum. cloning of the f2 promoter into the pjup05 promoter probe vector caused an increase of the neomycin phosphotransferase ii specific activity. according to the northern blot hybridization the nptii gene was expressed from the cloned f2 promoter. the apparent transcription start point in e. coli and c. glutamicum was determined. the -35 region of f2 promoter showe ... | 1994 | 7879712 |
| structure of the gluabcd cluster encoding the glutamate uptake system of corynebacterium glutamicum. | to assess the mechanism and function of the glutamate uptake system of gram-positive corynebacterium glutamicum, a mutant deficient in glutamate uptake was isolated and was then used to isolate a dna fragment restoring this deficiency. in a low-copy-number vector, this fragment resulted in an increased glutamate uptake rate of 4.9 nmol/min/mg (wild type, 1.5 nmol/min/mg). in addition, carbon source-dependent regulation of the glutamate uptake system was determined with the fragment, showing that ... | 1995 | 7868586 |
| nucleotide sequence of a reca gene from corynebacterium glutamicum. | the nucleotide sequence of the reca gene from corynebacterium glutamicum as019 was determined by sequencing a number of overlapping clones containing genomic dna. comparison of the c. glutamicum reca gene sequence to the sequences of other procaryotic reca genes reveals a high degree of identity of both the dna and inferred amino acid sequences. | 1994 | 7841463 |
| cloning, sequence analysis, expression, and inactivation of the corynebacterium glutamicum icd gene encoding isocitrate dehydrogenase and biochemical characterization of the enzyme. | nadp(+)-dependent isocitrate dehydrogenase (icd) is an important enzyme of the intermediary metabolism, as it controls the carbon flux within the citric acid cycle and supplies the cell with 2-oxoglutarate and nadph for biosynthetic purposes. in the amino acid-producing organism corynebacterium glutamicum, the specific activity of icd was independent of the growth substrate and of the growth phase at approximately 1 u/mg, indicating that this enzyme is constitutively formed. the icd gene, icd, w ... | 1995 | 7836312 |
| threonine dehydratases of corynebacterium glutamicum with altered allosteric control: their generation and biochemical and structural analysis. | threonine dehydratase is the key enzyme in l-isoleucine synthesis, since it is allosterically feedback-inhibited by l-isoleucine. with the aim of obtaining regulatorily altered mutants of the threonine dehydratase of corynebacterium glutamicum, amino acids were specifically exchanged and a new biological system of mutant selection was developed, based on the intoxication of escherichia coli by ketobutyrate, which is the dehydratase reaction product. a collection of 19 mutant enzymes was generate ... | 1994 | 7815942 |
| molecular cloning, dna sequence analysis, and characterization of the corynebacterium diphtheriae dtxr homolog from brevibacterium lactofermentum. | a homolog of the corynebacterium diphtheriae dtxr gene was isolated from brevibacterium lactofermentum. the product of the b. lactofermentum dtxr gene was immunoreactive with polyclonal anti-dtxr antibodies and functioned as an iron-activated repressor capable of regulating the expression of beta-galactosidase from a diphtheria tox promoter/operator transcriptional fusion in recombinant escherichia coli. the extents of induction by increasing concentrations of the chelator 2,2'-dipyridyl were id ... | 1995 | 7814338 |
| malate synthase from corynebacterium glutamicum: sequence analysis of the gene and biochemical characterization of the enzyme. | malate synthase is one of the key enzymes of the glyoxylate cycle and is essential for growth on acetate as sole carbon source. the aceb gene from corynebacterium glutamicum, encoding malate synthase, was isolated, subcloned and expressed in escherichia coli and c. glutamicum. sequencing of a 3024 bp dna fragment containing the aceb gene revealed that it is located close to the isocitrate lyase gene acea. the two genes are separated by 597 bp and are transcribed in divergent directions. the pred ... | 1994 | 7812449 |
| transposon mutagenesis of coryneform bacteria. | the corynebacterium glutamicum insertion sequence is31831 was used to construct two artificial transposons: tn31831 and minitn31831. the transposition vectors were based on a gram-negative replication origin and do not replicate in coryneform bacteria. strain brevibacterium flavum mj233c was mutagenized by minitn31831 at an efficiency of 4.3 x 10(4) mutants per microgram dna. transposon insertions occurred at different locations on the chromosome and produced a variety of mutants. auxotrophs cou ... | 1994 | 7808388 |
| purification and properties of oxaloacetate decarboxylase from corynebacterium glutamicum. | oxaloacetate (oaa) decarboxylase (e.c. 4.1.1.3) was isolated from corynebacterium glutamicum. in five steps the enzyme was purified 300-fold to apparent homogeneity. the molecular mass estimated by gel filtration was 118 +/- 6 kda. sds-page showed a single subunit of 31.7 kda, indicating an alpha 4 subunit structure for the native enzyme. the enzyme catalyzed the decarboxylation of oaa to pyruvate and co2, but no other alpha-ketoacids were used as substrate. the cation mn2+ was required for full ... | 1995 | 7771770 |
| effect of different levels of aspartokinase on the lysine production by corynebacterium lactofermentum. | a 2.9-kb saci fragment containing the ask-asd operon, encoding aspartokinase and aspartatesemialdehyde dehydrogenase, was cloned from an aminoethylcysteine-resistant, lysine-producing corynebacterium lactofermentum strain. enzymatic analysis showed that the aspartokinase (ask) activity was completely resistant to inhibition by mixtures of lysine and threonine. comparison of the deduced amino acid sequence of the beta submit of the ask gene showed three amino acid residue changes with ask gene en ... | 1995 | 7766138 |
| construction of a new host-vector system in arthrobacter sp. and cloning of the lipase gene. | arthrobacter sp. strain mis38 was transformed with a shuttle vector containing the kanamycin resistant gene kan (derived from tn5) by an electroporation method. this shuttle vector is from brevibacterium lactofermentum and escherichia coli, pulrs8. the following optimal condition of electroporation was determined. a square wave pulse of 1 kv/cm electric field strength for 0.5 ms duration yielded 3 x 10(5) transformants/micrograms plasmid dna. the number of transformants increased with the amount ... | 1994 | 7765770 |
| construction and characterization of reca mutant strains of corynebacterium glutamicum and brevibacterium lactofermentum. | an internal fragment of the corynebacterium glutamicum reca gene was amplified by the polymerase chain reaction (pcr) using degenerate primers corresponding to two short sequences that are well conserved in procaryotic reca proteins. the deduced amino acid sequence of the amplified fragment shared significant homology with reca sequences from other bacteria including the "invariant" and functionally conserved amino acids leu-126, asp-144, gly-157, arg-169 and asn-193. highest identity (91%) was ... | 1994 | 7765733 |
| sensitivity of translation by brevibacterium lactofermentum ribosomes to type 1 and type 2 ribosome-inactivating proteins. | an active cell-free translation system was prepared from brevibacterium lactofermentum, a gram-positive bacteria used in molecular cloning and protein expression. the system contained high speed postribosomal supernatant (s 370), purified ribosomes and a trna mixture from escherichia coli, and synthesized polyuridylic acid-directed polyphenylalanine once optimized for mono and divalent ions, time, and temperature. the translation system was evaluated for sensitivity to several translational inhi ... | 1994 | 7765276 |
| factors improving l-threonine production by a three l-threonine biosynthetic genes-amplified recombinant strain of brevibacterium lactofermentum. | when a brevibacterium lactofermentum l-threonine producer that accumulated l-lysine as well, was transformed with a recombinant plasmid carrying the indigenous hom, thrb, and thrc genes, delayed growth and plasmid instability were observed. addition of organic nutrients, vitamins (thiamine.hcl and d-biotin), and nacl under the optimal culture conditions solved these problems and further increased threonine production in a small jar fermentor. | 1994 | 7764868 |
| fermentative production of tryptophan by a stable recombinant strain of corynebacterium glutamicum with a modified serine-biosynthetic pathway. | introduction of plasmid pkw99, which coexpresses the deregulated 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase and tryptophan-biosynthetic enzymes, into tryptophan-producing corynebacterium glutamicum ky10894 resulted in a marked increase (54%) in yield of tryptophan production (43 g/liter), but incurred two problems. one was a decline in sugar consumption at the late stage of fermentation, and the other the loss of the plasmid in the absence of selective pressure. the retarded sugar assi ... | 1994 | 7764859 |
| cloning of the atp phosphoribosyl transferase gene of corynebacterium glutamicum and application of the gene to l-histidine production. | corynebacterium glutamicum mutants lacking atp phosphoribosyl transferase (prt) were selected by complementation with the escherichia coli prt gene. the recombinant plasmid pch13 carrying a wild type prt gene from c. glutamicum t106 was obtained in one of the mutants, lh13. transformants, lh13/pch13 and t106/pch13, had three times higher prt specific activity than t106. the plasmid pch99 specifying the prt, which was desensitized to feedback inhibition by l-histidine fifty-fold higher than the w ... | 1994 | 7764856 |
| production of intracellular enzyme by corynebacterium glutamicum t6-13 protoplasts immobilized in ca-alginate gels. | the glutamate dehydrogenase (gdh) (ec 1.4.1.4) productivity of the immobilized corynebacterium glutamicum t6-13 protoplasts in ca-alginate gels was investigated. gdh in corynebacterium glutamicum t6-13 cells is an intracellular enzyme. the cells pretreated with 0.5 u/l-1 penicillin g were used for the preparation of protoplasts. protoplasts were prepared by treating these cells with lysozyme at 30 degrees c for 14 h in 0.5 m nacl solution and separating the protoplasts. protoplasts were directly ... | 1993 | 7764008 |
| isolation and physico-chemical characterization of an antifungal and antibacterial peptide produced by bacillus licheniformis a12. | an antifungal substance named peptide a12-c has been purified to homogeneity from supernatants of sporulated cultures of bacillus licheniformis a12. it consists of a 0.77-kda hydrophilic peptide containing two residues of glu and one of arg, ala, pro, tyr and orn. no fatty acids, phosphorus or carbohydrates have been detected. peptide a12-c is active on several fungi (microsporum canis cect 2797, mucor mucedo cect 2653, m. plumbeus (ccm f 443, sporothrix schenckii cect 2799 and trichophyton ment ... | 1993 | 7763922 |
| phenylalanine production by metabolically engineered corynebacterium glutamicum with the phea gene of escherichia coli. | the bifunctional enzyme chorismate mutase (cm)-prephenate dehydratase (pd), which is encoded by the phea gene of escherichia coli, catalyses the two consecutive key steps in phenylalanine biosynthesis. to utilize the enzyme for metabolic engineering of phenylalanine-producing corynebacterium glutamicum ky10694, the intact gene was cloned on a multicopy vector to yield pea11.c. glutamicum cells transformed with pea11 exhibited a more than tenfold increase in cm and pd activities relative to the h ... | 1993 | 7763713 |
| functional expression of the glutamate uptake system from corynebacterium glutamicum in escherichia coli. | glutamate uptake in the gram-positive corynebacterium glutamicum is mediated via a binding protein-dependent transport system, which is encoded by the gluabcd gene cluster. cloning of these genes in an expression vector and subsequent transformation of the resulting plasmid allows different strains of the gram-negative bacterium escherichia coli to grow on glutamate as sole carbon and nitrogen source. however, overexpression of the glutamate uptake system results in growth inhibitory effects, pr ... | 1995 | 7758940 |
| prephenate dehydratase of the actinomycete amycolatopsis methanolica: purification and characterization of wild-type and deregulated mutant proteins. | prephenate dehydratase (pdt) is a key regulatory enzyme in l-phenylalanine biosynthesis in the gram-positive bacterium amycolatopsis methanolica. the pdt protein was purified to homogeneity (1957-fold) from wild-type cells with a final yield of 6.5%. it was characterized as a 150 kda homotetrameric protein with a subunit size of 34 kda. the first 35 n-terminal amino acids were identified, revealing highest similarity to the pdt proteins from corynebacterium glutamicum and bacillus subtilis. kine ... | 1995 | 7755580 |
| expression and secretion of heterologous proteases by corynebacterium glutamicum. | genes encoding the basic protease of dichelobacter nodosus (bprv) and the subtilisin of bacillus subtilis (apre) were cloned and expressed in corynebacterium glutamicum. in each case, enzymatically active protein was detected in the supernatants of liquid cultures. while the secretion of subtilisin was directed by its own signal peptide, the natural signal peptide of the bprv basic protease did not facilitate secretion. a hybrid apre-bprv gene in which the promoter and signal peptide coding sequ ... | 1995 | 7747974 |
| recent advances in the physiology and genetics of amino acid-producing bacteria. | corynebacterium glutamicum and its close relatives, c. flavum and c. lactofermentum, have been used for over 3 decades in the industrial production of amino acids by fermentation. since 1984, several research groups have started programs to develop metabolic engineering principles for amino acid-producing corynebacterium strains. initially, the programs concentrated on the isolation of genes encoding (deregulated) biosynthetic enzymes and the development of general molecular biology tools such a ... | 1995 | 7736600 |
| transcriptional analysis of the gap-pgk-tpi-ppc gene cluster of corynebacterium glutamicum. | the transcriptional organization of the corynebacterium glutamicum gap-pgk-tpi-ppc gene cluster, encoding glyceraldehyde-3-phosphate dehydrogenase, 3-phosphoglycerate kinase, triosephosphate isomerase, and phosphoenolpyruvate carboxylase, was investigated by northern (rna) blot and primer extension analyses. four transcripts corresponding to gap, to gap-pgk-tpi, to pgk-tpi, and to pgk-tpi-ppc were identified. the respective transcriptional initiation sites in front of gap and pgk were located, a ... | 1993 | 7685337 |
| cloning of the trp gene cluster from a tryptophan-hyperproducing strain of corynebacterium glutamicum: identification of a mutation in the trp leader sequence. | corynebacterium glutamicum atcc 21850 produces up to 5 g of extracellular l-tryptophan per liter in broth culture and displays resistance to several synthetic analogs of aromatic amino acids. here we report the cloning of the tryptophan biosynthesis (trp) gene cluster of this strain on a 14.5-kb bamhi fragment. subcloning and complementation of escherichia coli trp auxotrophs revealed that as in brevibacterium lactofermentum, the c. glutamicum trp genes are clustered in an operon in the order tr ... | 1993 | 7683184 |
| gene replacement, integration, and amplification at the gdha locus of corynebacterium glutamicum. | gene replacement and integration in a corynebacterium glutamicum atcc 21086 derivative were achieved by transformation with a nonreplicative plasmid that contains the c. glutamicum atcc 17965 gdha gene modified by the insertion of an aphiii cartridge. we isolated rare derivatives of the integrative transformants that have higher levels of expression of the integrated plasmid genes than the parent. different types of such amplified clones were distinguished according to their antibiotic resistanc ... | 1993 | 7679382 |
| glycine betaine uptake after hyperosmotic shift in corynebacterium glutamicum. | osmoregulatory uptake of glycine betaine in whole cells of corynebacterium glutamicum atcc 13032 (wild type) was studied. the cells actively take up glycine betaine when they are osmotically shocked. the total accumulation and uptake rate were dependent on the osmotic strength of the medium. kinetic analysis revealed a high-affinity transport system (km, 8.6 +/- 0.4 microm) with high maximum velocity (110 nmol.min-1.mg [dry weight]-1). glycine betaine functioned as a compatible solute when added ... | 1995 | 7642496 |
| the biosynthesis of threonine by mammalian cells: expression of a complete bacterial biosynthetic pathway in an animal cell. | the coding regions for the escherichia coli gene for aspartokinase i/homoserine dehydrogenase i (thra) and the corynebacterium glutamicum gene for aspartic semialdehyde dehydrogenase (asd) have been subcloned into a simian virus 40 (sv40)-based mammalian expression vector. both enzyme activities are expressed in mouse 3t3 cells after transfer of the corresponding chimaeric gene. the kinetic parameters are similar to those of the native bacterial enzymes, and aspartokinase i/homoserine dehydrogen ... | 1995 | 7639721 |
| production of isoleucine by overexpression of ilva in a corynebacterium lactofermentum threonine producer. | overproduction of isoleucine, an essential amino acid, was achieved by amplification of the gene encoding threonine dehydratase, the first enzyme in the threonine to isoleucine pathway, in a corynebacterium lactofermentum threonine producer. threonine overproduction was previously achieved with c. lactofermentum atcc 21799, a lysine-hyperproducing strain, by introduction of plasmid pgc42 containing the corynebacterium homdr and thrb genes (encoding homoserine dehydrogenase and homoserine kinase ... | 1995 | 7632398 |
| construction of lysine-producing strains by gene disruption and replacement in brevibacterium divaricatum. | gene disruption and replacement techniques were applied to block the biosynthesis of threonine and methionine and thus to construct genetically stable lysine producers in a glutamate-producing bacteria, brevibacterium divaricatum. the homoserine dehydrogenase gene (hom), homoserine kinase gene (thrb) and hom-thrb operon were amplified as 1.8, 1.25 and 2.8 kb fragments from b. divaricatum by polymerase chain reaction (pcr) and cloned in an e. coli-coryneform bacteria shuttle vector, psumn18. thes ... | 1995 | 7624444 |
| unbalance of l-lysine flux in corynebacterium glutamicum and its use for the isolation of excretion-defective mutants. | we found that the simple addition of l-methionine to the wild type of corynebacterium glutamicum results in excretion of the cellular building block l-lysine up to rates of 2.5 nmol/min/mg (dry weight). biochemical analyses revealed that l-methionine represses the homoserine dehydrogenase activity and reduces the intracellular l-threonine level from 7 to less than 2 mm. since l-lysine synthesis is regulated mainly by l-threonine (plus l-lysine) availability, the result is enhanced flux towards l ... | 1995 | 7608075 |
| functional analysis of sequences adjacent to dape of corynebacterium glutamicum reveals the presence of arop, which encodes the aromatic amino acid transporter. | an initially nonclonable dna locus close to a gene of l-lysine biosynthesis in corynebacterium glutamicum was analyzed in detail. its stepwise cloning and its functional identification by monitoring the amino acid uptakes of defined mutants, together with mechanistic studies, identified the corresponding structure as arop, the general aromatic amino acid uptake system. | 1995 | 7592354 |
| the erythromycin resistance gene of the corynebacterium xerosis r-plasmid ptp10 also carrying chloramphenicol, kanamycin, and tetracycline resistances is capable of transposition in corynebacterium glutamicum. | the clinical isolate corynebacterium xerosis m82b carries the 50-kb r-plasmid ptp10 that confers resistance to the antibiotics chloramphenicol, kanamycin, erythromycin, and tetracycline. a detailed restriction map of ptp10 was constructed by cloning and analyzing restriction fragments of ptp10 in escherichia coli. the resistance determinants of ptp10 were located by studying the phenotype of the recombinant plasmids in e. coli and corynebacterium glutamicum. restriction patterns of fragments enc ... | 1995 | 7568464 |