Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| inhibition of human nk cell function by valinomycin, a toxin from streptomyces griseus in indoor air. | streptomyces griseus strains isolated from indoor dust have been shown to synthesize valinomycin. in this report, we show that human peripheral blood lymphocytes treated with small doses (30 ng ml(-1)) of pure valinomycin or high-pressure liquid chromatography-pure valinomycin from s. griseus quickly show mitochondrial swelling and reduced nk cell activity. larger doses (>100 ng/ml(-1)) induced nk cell apoptosis within 2 days. within 2 h, the toxin at 100 ng ml(-1) dramatically inhibited interle ... | 2000 | 10603383 |
| family 19 chitinases of streptomyces species: characterization and distribution. | chitinase c from streptomyces griseus hut6037, described in 1997, is the first family 19 chitinase found in an organism other than higher plants. in this study, some properties of chitinase c were compared with those of family 18 bacterial chitinases, and the distribution of family 19 chitinases in streptomyces species was investigated. the specific hydrolysing activity of chitinase c against soluble and insoluble chitinous substrates was markedly higher than those of bacterial family 18 chitina ... | 1999 | 10627034 |
| identification and characterization of the point mutation which affects the transcription level of the chromosomal 3-n-acetyltransferase gene of streptomyces griseus ss-1198. | we determined the molecular basis for the enhanced expression of the aac(3)-xa gene encoding an aminoglycoside 3-n-acetyltransferase in streptomyces griseus. a c-->t substitution was identified at the putative promoter of the mutant gene. rna analyses demonstrated that the substitution caused a marked increase in the production of the gene-specific transcripts. therefore, it seemed very likely that the aac(3)-xa gene was activated by the substitution resulting in the emergence of a stronger prom ... | 2000 | 10639379 |
| nonactin biosynthesis: the potential nonactin biosynthesis gene cluster contains type ii polyketide synthase-like genes. | nonactin is the parent compound of a group of highly atypical polyketide metabolites produced by streptomyces griseus subsp. griseus eth a7796. in this paper we describe the isolation, sequencing, and analysis of 15¿ omitted¿559 bp of chromosomal dna, containing the potential nonactin biosynthesis gene cluster, from s. griseus subsp. griseus eth a7796. fourteen open reading frames were observed in the dna sequence. significantly, type ii polyketide synthase (pks) homologues were discovered in an ... | 2000 | 10650222 |
| cloning, expression, and substrate specificity of a fungal chymotrypsin. evidence for lateral gene transfer from an actinomycete bacterium. | unlike trypsins, chymotrypsins have not until now been found in fungi. expressed sequence tag analysis of the deuteromycete metarhizium anisopliae identified two trypsins (family s1) and a novel chymotrypsin (chy1). chy1 resembles actinomycete (bacterial) chymotrypsins (family s2) rather than other eukaryote enzymes (family s1) in being synthesized as a precursor species (374 amino acids, pi/mw: 5.07/38,279) containing a large n-terminal fragment (186 amino acids). chy1 was expressed in pichia p ... | 2000 | 10692479 |
| active-site variants of streptomyces griseus protease b with peptide-ligation activity. | peptide-ligating technologies facilitate a range of manipulations for the study of protein structure and function that are not possible using conventional genetic or mutagenic methods. to different extents, the currently available enzymatic and nonenzymatic methodologies are synthetically demanding, sequence-dependent and/or sensitive to denaturants. no single coupling method is universally applicable. accordingly, new strategies for peptide ligation are sought. | 2000 | 10712933 |
| deleterious effects of beta-branched residues in the s1 specificity pocket of streptomyces griseus proteinase b (sgpb): crystal structures of the turkey ovomucoid third domain variants ile18i, val18i, thr18i, and ser18i in complex with sgpb. | turkey ovomucoid third domain (omtky3) is a canonical inhibitor of serine proteinases. upon complex formation, the inhibitors fully exposed p1 residue becomes fully buried in the preformed cavity of the enzyme. all 20 p1 variants of omtky3 have been obtained by recombinant dna technology and their equilibrium association constants have been measured with six serine proteinases. to rationalize the trends observed in this data set, high resolution crystal structures have been determined for omtky3 ... | 2000 | 10739250 |
| interactions of streptomyces griseus aminopeptidase with a methionine product analogue: a structural study at 1.53 a resolution. | sgap is an aminopeptidase present in the extracellular fluid of streptomyces griseus cultures. it is a double-zinc enzyme with a strong preference for large hydrophobic amino-terminus residues. it is a monomeric (30 kda) heat-stable enzyme, with a high and efficient catalytic activity modulated by calcium ions. the small size, high activity and heat stability make sgap a very attractive enzyme for various biotechnological applications. only one other related aminopeptidase (aeromonas proteolytic ... | 2000 | 10771423 |
| overexpression of the lat gene in nocardia lactamdurans from strong heterologous promoters results in very high levels of lysine-6-aminotransferase and up to two-fold increase in cephamycin c production. | the level of lysine-6-aminotransferase (encoded by the lat gene), an enzyme that commits lysine to the cephamycin biosynthesis pathway, is very low in wild type nocardia lactamdurans. two lat overexpression systems (pamexlat and psaflat) were constructed to express the promoterless lat gene of n. lactamdurans from the strong promoters amyp (of the alpha-amylase gene) and safp (of the secretion activating factor gene) of streptomyces griseus. both constructions led to very high levels of lysine-6 ... | 2000 | 10772467 |
| genetic localization and molecular characterization of the nons gene required for macrotetrolide biosynthesis in streptomyces griseus dsm40695. | the macrotetrolides are a family of cyclic polyethers derived from tetramerization, in a stereospecific fashion, of the enantiomeric nonactic acid (na) and its homologs. isotope labeling experiments established that na is of polyketide origin, and biochemical investigations demonstrated that 2-methyl-6,8-dihydroxynon-2e-enoic acid can be converted into na by a cell-free preparation from streptomyces lividans that expresses nons. these results lead to the hypothesis that macrotetrolide biosynthes ... | 2000 | 10858335 |
| control of il-5 production by human helper t cells as a treatment for eosinophilic inflammation: comparison of in vitro and in vivo effects between selective and nonselective cytokine synthesis inhibitors. | helper t cells are involved in the pathophysiologic condition of asthma, so modulation of cytokine production may be effective therapy. | 2000 | 10887335 |
| an a-factor-dependent extracytoplasmic function sigma factor (sigma(adsa)) that is essential for morphological development in streptomyces griseus. | a-factor (2-isocapryloyl-3r-hydroxymethyl-gamma-butyrolactone) at an extremely low concentration triggers streptomycin production and aerial mycelium formation in streptomyces griseus. a-factor induces the expression of an a-factor-dependent transcriptional activator, adpa, essential for both morphological and physiological differentiation by binding to the a-factor receptor protein arpa, which has bound and repressed the adpa promoter, and dissociating it from the promoter. nine dna fragments t ... | 2000 | 10913094 |
| an oligoribonuclease gene in streptomyces griseus. | in streptomyces griseus, a-factor (2-isocapryloyl-3r-hydroxymethyl-gamma-butyrolactone) serves as a microbial hormone that switches on many genes required for streptomycin production and morphological development. an open reading frame (orf1) showing high sequence similarity to oligoribonucleases of various origins is present just downstream of adpa, one of the a-factor-dependent genes. orf1 was named orna (oligoribonuclease a) because it showed 3'-to-5' exo-oligoribonuclease activity, releasing ... | 2000 | 10913103 |
| determination of metabolic activity of streptomycetes in soil microcosms. | two streptomyces griseus strains were isolated from different soil types. s. griseus cag17 strain was isolated from an agricultural area with low organic matter but rich in phosphorus content and s. griseus 26k strain was isolated from a forest area rich in organic matter with a low phosphorus content. the survival and metabolic activity of these isolates were studied in dynamic sterile soil microcosm systems. the fitness of each isolate was studied by re-inoculation in a soil type different fro ... | 2000 | 10945795 |
| a synthetic gamma-lactone group with beta-lactamase inhibitory and sporulation initiation effects. | previous studies showed that some lactones have beta-lactamase inhibitory or antibacterial effects, others--like a-factor (a gamma-butyrolactone) and its derivatives--stimulate sporulation in streptomyces griseus strains. our experiments were aimed at exploring whether synthetic gamma-lactones had such effects. none of the seven gamma-lactones studied showed antibacterial activity, but two of them inhibited beta-lactamases isolated from various bacteria. these two gamma-lactones did not reduce c ... | 2000 | 10949975 |
| identification of cis site involved in nickel-responsive transcriptional repression of sodf gene coding for fe- and zn-containing superoxide dismutase of streptomyces griseus. | a sodf gene coding for iron- and zinc-containing superoxide dismutase (feznsod) of streptomyces griseus was cloned and sequenced. a 5' end of 0.8-kb sodf transcript was mapped at the 57 nucleotides upstream from an atg initiation codon. employing expressions of sodf::xyle fusions in trans in streptomyces lividans, nickel-responsive transcriptional repression was found to be relieved if mutations were introduced into an operator sequence of inverted-repeat, ttgcan(7)tgcaa, which traverses the 5' ... | 2000 | 10978523 |
| characterization of ssfr and ssga, two genes involved in sporulation of streptomyces griseus. | in the presence of cefoxitin, which inhibits septum formation during sporulation, streptomyces griseus is unable to sporulate, retaining the sonication sensitivity of nonsporulating hyphae. cefoxitin- and sonication-resistant mutant skk2600 was isolated and showed many morphological differences from its parental strain. a 3.6-kb dna fragment that complemented the mutations of skk2600 contained two open reading frames (orfs), either of which could complement skk2600. one orf, designated ssfr, enc ... | 2000 | 10986257 |
| engineering of heterologous cytochrome p450 in acinetobacter sp.: application for pollutant degradation. | many organisms do not contain the necessary biochemical armoury to carry out the initial oxidative attack of many pollutant chemicals. in the present study, acinetobacter sp. strain bd413 has been genetically engineered to express the cytochrome p450 xenobiotic-metabolising enzyme cyp105d1 from streptomyces griseus that has in its repertoire a diverse array of organic pollutants. further, it is shown that the transformed acinetobacter calcoaceticus strain bd413 can grow on pollutants unlike cont ... | 2000 | 11027550 |
| purification and characterization of streptomyces griseus catechol o-methyltransferase. | a soluble (100,000 x g supernatant) methyltransferase catalyzing the transfer of the methyl group of s-adenosyl-l-methionine to catechols was present in cell extracts of streptomyces griseus. a simple, general, and rapid catechol-based assay method was devised for enzyme purification and characterization. the enzyme was purified 141-fold by precipitation with ammonium sulfate and successive chromatography over columns of deae-cellulose, deae-sepharose, and sephacryl s-200. the purified cytoplasm ... | 2000 | 11055938 |
| peptide sequence information derived by pronase digestion and ammonium sulfate in-source decay matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. | we present the use of pronase digestion and in-source decay in the presence of ammonium sulfate as complementary techniques to confirm the amino acid sequence of a peptide. pronase, a commercial preparation from streptomyces griseus, is a combination of proteolytic enzymes. it produces carboxypeptidase and aminopeptidase ladders using a single pronase digestion and represents an inexpensive, nonspecific, and fast supplement to traditional sequencing enzymes. however, n-terminal peptidase activit ... | 2000 | 11073263 |
| cloning and characterization of the gene encoding penicillin-binding protein a of streptomyces griseus. | an internal segment of the penicillin-binding protein gene, pbpa, of streptomyces griseus was amplified from genomic dna using the polymerase chain reaction and used as a hybridization probe to isolate the complete gene from a cosmid library. pbpa encodes a 485 amino acid sequence that conserves three motifs of pbps, sxxk, sxn, and ktg. the pbpa gene was located downstream of a gene homologous to the bacillus subtilis spove gene. the pbpa gene was disrupted by replacing an apai fragment of the p ... | 2000 | 11094280 |
| feigrisolides a, b, c and d, new lactones with antibacterial activities from streptomyces griseus. | four new lactone compounds, named feigrisolides a to d (1 to 4), have been isolated from streptomyces griseus. the chemical structures were determined by detail analysis of their spectroscopic data and chemical transformations. structurally, the feigrisolides a (1) and b (2) are hepta-lactones, feigrisolide c (3) and d (4) are 16-membered macrodiolides. biological studies showed that feigrisolide b (2) exhibited strong antibacterial, as well as medium cyctotoxic, and antiviral activities. feigri ... | 2000 | 11099227 |
| cofactor recycling with immobilized heterologous cytochrome p450 105d1 (cyp105d1). | immobilisation of cells and enzymes can be a convenient and rapid way for testing and transforming substances. cytochromes p450 may be useful in numerous biotransformations of varied lipophilic substrates, performing both regio- and stereo-specific monooxygenation reactions. however, one limitation of their use in vitro is the requirement of cofactor for the supply of electrons in the catalytic cycle. here we report cyp105d1 from streptomyces griseus expressed in escherichia coli can be immobili ... | 2000 | 11118349 |
| anionic trypsin from chum salmon: activity with p-amidinophenyl ester and comparison with bovine and streptomyces griseus trypsins. | an anionic trypsin from pyloric caeca of chum salmon (oncorhynchus keta) was purified by ammonium sulfate and acetone fractionation followed by affinity chromatography, gel-filtration, and deae-anion exchange chromatography. the apparent molecular mass was about 24 kda as determined by sds-page. the anionic chum salmon trypsin was moderately active toward esterase substrates such as tosyl-l-arginine methyl ester and tosyl-l-lysine methyl ester. its amidase activity for benzoyl-l-arginine p-nitro ... | 2000 | 11126764 |
| polysaccharide lyase: molecular cloning, sequencing, and overexpression of the xanthan lyase gene of bacillus sp. strain gl1. | when grown on xanthan as a carbon source, the bacterium bacillus sp. strain gl1 produces extracellular xanthan lyase (75 kda), catalyzing the first step of xanthan depolymerization (h. nankai, w. hashimoto, h. miki, s. kawai, and k. murata, appl. environ. microbiol. 65:2520-2526, 1999). a gene for the lyase was cloned, and its nucleotide sequence was determined. the gene contained an open reading frame consisting of 2,793 bp coding for a polypeptide with a molecular weight of 99,308. the polypep ... | 2001 | 11157235 |
| contribution of peptide bonds to inhibitor-protease binding: crystal structures of the turkey ovomucoid third domain backbone variants omtky3-pro18i and omtky3-psi[coo]-leu18i in complex with streptomyces griseus proteinase b (sgpb) and the structure of the free inhibitor, omtky-3-psi[ch2nh2+]-asp19i. | x-ray crystallography has been used to determine the 3d structures of two complexes between streptomyces griseus proteinase b (sgpb), a bacterial serine proteinase, and backbone variants of turkey ovomucoid third domain (omtky3). the natural p1 residue (leu18i) has been substituted by a proline residue (omtky3-pro18i) and in the second variant, the peptide bond between thr17i and leu18i was replaced by an ester bond (omtky3-psi[coo]-leu18i). both variants lack the p1 nh group that donates a bifu ... | 2001 | 11162096 |
| cloning and expression of thermophilic catechol 1,2-dioxygenase gene (cata) from streptomyces setonii. | streptomyces setonii (atcc 39116) degrades various single aromatic compounds such as phenol or benzoate via an ortho-cleavage pathway using catechol 1,2-dioxygenase (c12o). a pcr using degenerate primers based on the conserved regions of known c12o-encoding genes amplified a 0.45-kbp dna fragment from s. setonii total dna. a southern hybridization analysis and size-selected dna library screening using the 0.45-kbp pcr product as a probe led to the isolation of a 6.4-kbp s. setonii dna fragment, ... | 2001 | 11166989 |
| a sigmab-like factor responsible for carotenoid biosynthesis in streptomyces griseus. | self-cloning experiments with a high-copy-number plasmid and streptomyces griseus ifo13350 led to the cloning of a 11-kb dna fragment that conferred yellow pigment production on the host. the cloned fragment contained a gene cluster for carotenoid biosynthesis, in which two polycistrons, crte (encoding geranylgeranyl pyrophosphate synthase)-crti (phytoene dehydrogenase)-crtb (phytoene synthase)-crtv (functionally unknown methyltransferase-like protein) and crty (lycopene cyclase)-crtt (functiona ... | 2001 | 11200234 |
| sequence analysis of the aminoacylase-1 family. a new proposed signature for metalloexopeptidases. | the amino acid sequence analysis of the human and porcine aminoacylases-1, the carboxypeptidase s precursor from saccharomyces cerevisiae, the succinyl-diaminopimelate desuccinylase from escherichia coli, haemophilus influenzae and corynebacterium glutamicum, the acetylornithine deacetylase from escherichia coli and dictyostelium discoideum and the carboxypeptidase g(2) precursor from pseudomonas strain, using the basic local alignment search tool (blast) and the position-specific iterated blast ... | 2001 | 11250542 |
| expression and rapid one-step purification of biologically active his-tagged factor c by ni(2+) affinity column chromatography. | factor c is an unusual extracellular protein capable of inducing cytodifferentiation in certain streptomyces strains. the protein is produced by streptomyces griseus 45h at such a low amount that the study of its mode of action was hindered by the shortage of purified protein. we report here the expression of c-terminally hexa-his-tagged factor c in streptomyces lividans and escherichia coli. expression in s. lividans is low while in e. coli it is relatively high, yielding about 5--10 mg of biol ... | 2001 | 11267783 |
| reduction of infectious epizootic hemorrhagic disease virus associated with in vitro produced bovine embryos by non-specific protease. | infectious viruses bind more tenaciously to the zonae pellucidae of in vitro produced bovine embryos than to zonae of in vivo derived embryos. currently, the international embryo transfer society recommends that all in vivo derived embryos be subjected to a rigorous washing procedure in combination with exposure to trypsin to remove viruses adherent to the zonae. in contrast to in vivo derived embryos, this method is not effective for disinfecting in vitro produced embryos. our hypothesis was th ... | 2001 | 11267800 |
| a functional myo-inositol dehydrogenase gene is required for efficient nitrogen fixation and competitiveness of sinorhizobium fredii usda191 to nodulate soybean (glycine max [l.] merr.). | inositol derivative compounds provide a nutrient source for soil bacteria that possess the ability to degrade such compounds. rhizobium strains that are capable of utilizing certain inositol derivatives are better colonizers of their host plants. we have cloned and determined the nucleotide sequence of the myo-inositol dehydrogenase gene (idha) of sinorhizobium fredii usda191, the first enzyme responsible for inositol catabolism. the deduced idha protein has a molecular mass of 34,648 da and sho ... | 2001 | 11274120 |
| metal ion binding and activation of streptomyces griseus dinuclear aminopeptidase: cadmium(ii) binding as a model. | a detailed metal binding and activation of the dinuclear aminopeptidase from streptomyces griseus (sap) has been analyzed and modeled by means of metal titration as well as kinetic and thermodynamic techniques using cd2+ as a probe. cd2+ binds to the two metal-binding sites in a sequential manner to produce a very active cd2+-substituted derivative, particularly in the presence of ca2+ (53% and 90%, respectively, relative to the activities of the native form in terms of kcat/km under the same co ... | 2001 | 11293404 |
| export of cytochrome p450 105d1 to the periplasmic space of escherichia coli. | cyp105d1, a cytochrome p450 from streptomyces griseus, was appended at its amino terminus to the secretory signal of escherichia coli alkaline phosphatase and placed under the transcriptional control of the native phoa promoter. heterologous expression in e. coli phosphate-limited medium resulted in abundant synthesis of recombinant cyp105d1 that was translocated across the bacterial inner membrane and processed to yield authentic, heme-incorporated p450 within the periplasmic space. cell extrac ... | 2001 | 11319092 |
| kinetics of methyl t-butyl ether cometabolism at low concentrations by pure cultures of butane-degrading bacteria. | butane-oxidizing arthrobacter (atcc 27778) bacteria were shown to degrade low concentrations of methyl t-butyl ether (mtbe; range, 100 to 800 microg/liter) with an apparent half-saturation concentration (k(s)) of 2.14 mg/liter and a maximum substrate utilization rate (k(c)) of 0.43 mg/mg of total suspended solids per day. arthrobacter bacteria demonstrated mtbe degradation activity when grown on butane but not when grown on glucose, butanol, or tryptose phosphate broth. the presence of butane, t ... | 2001 | 11319100 |
| hydroxylations and methylations of quercetin, fisetin, and catechin by streptomyces griseus. | preparative-scale biotransformation of quercetin (1), fisetin (7), and (+)-catechin (12) with streptomyces griseus (atcc 13273) resulted in the isolation and characterization of nine known hydroxylated and/or methylated (2--6, 8, 9, 11, 13a) metabolites and two previously unknown (10 and 14) metabolites. s.griseus catalyzed aromatic hydroxylations of rings a and b of quercetin and fisetin. mono- and dimethoxy ring-b metabolites were obtained with all three substrates. methylation appeared to occ ... | 2001 | 11325228 |
| identification and characterization of a developmentally regulated protein, esha, required for sporogenic hyphal branches in streptomyces griseus. | to identify sporulation-specific proteins that might serve as targets of developmental regulatory factors in streptomyces, we examined total proteins of streptomyces griseus by two-dimensional gel electrophoresis. among five proteins that were present at high levels during sporulation but absent from vegetative cells, two of the proteins, p3 and p4, were absent from developmental mutants that undergo aberrant morphogenesis. the deduced amino acid sequence of the gene that encodes p3 (esha) showe ... | 2001 | 11325927 |
| enhancement of chymotrypsin-inhibitor/substrate interactions by 3 m nacl. | a series of 16 bovine pancreatic trypsin inhibitor variants mutated at the p(1) position of the binding loop and seven tetrapeptide p-nitroanilide (pna) substrates of the general formula: suc-ala-ala-pro-aaa-pna (where aaa denotes either: phe, arg, lys, leu, met, nva, nle) were used to investigate the influence of high salt concentration on the activity of bovine chymotrypsin. the increase of the association constant (k(a)) and the specificity index (k(cat)/k(m)) in the presence of 3 m nacl high ... | 2001 | 11342033 |
| identification of a growth phase-dependent promoter in the rpljl operon of streptomyces coelicolor a3(2). | a single promoter, rpljp (p(l10)), has been identified in the rpljl operon from streptomyces coelicolor a3(2) by promoter probe and primer extension analyses. p(l10) is located upstream of the rpll gene and of the dna encoding the mrna leader region that contains the putative l10 (or l10.l12(4)) binding site for translational autogenous regulation. the potential start point for transcription was found 239 nucleotides upstream of the predicted translational start codon of rplj. the promoter seque ... | 2001 | 11342105 |
| carbon-source-dependent transcriptional control involved in the initiation of cellular differentiation in streptomyces griseus. | carbon source is one of the environmental factors that affects cellular differentiation of streptomyces. we have identified the craa gene as a putative negative regulator involved in the carbon-source-dependent initiation of cellular differentiation in streptomyces griseus. carbon-source-dependent transcriptional repression of craa, which is caused by binding of a putative repressor protein to its promoter region, is proposed to result in the initiation of aerial mycelium formation. the presence ... | 2000 | 11386348 |
| transcriptional and functional analysis of the gene for factor c, an extracellular signal protein involved in cytodifferentiation of streptomyces griseus. | factor c is an extracellular signal protein involved in cellular differentiation in streptomyces griseus. nuclease s1 mapping experiments revealed that transcription of the gene takes place from a single promoter in a developmental-stage specific manner. the latter was also confirmed by in vivo promoter probing. the sequence of its promoter suggests that the gene is not transcribed by the major sigma factor. the cloned gene expressed from its own promoter in low- and high-copy-number vectors res ... | 2000 | 11386350 |
| substrate analysis and molecular cloning of the extracellular alkaline phosphatase of streptomyces griseus. | streptomyces species secrete large amounts of alkaline phosphatase (ap) enzymes that have not been characterized so far. an ap has been purified to homogeneity from cultures of streptomyces griseus imru 3570. the enzyme has a monomer size of 62 kda and is processed in the culture to a 33 kda protein as shown by immunoblotting. the enzyme was purified by ammonium sulfate precipitation, cm-sephadex cationic exchange, chromatofocusing and hplc sphaerogel 3000sw filtration. the pure enzyme uses a va ... | 2001 | 11390683 |
| interactions of streptomyces griseus aminopeptidase with amino acid reaction products and their implications toward a catalytic mechanism. | streptomyces griseus aminopeptidase (sgap) is a double-zinc exopeptidase with a high preference toward large hydrophobic amino-terminus residues. it is a monomer of a relatively low molecular weight (30 kda), it is heat stable, it displays a high and efficient catalytic turnover, and its activity is modulated by calcium ions. the small size, high activity, and heat stability make sgap a very attractive enzyme for various biotechnological applications, among which is the processing of recombinant ... | 2001 | 11484227 |
| differential regulation of ftsz transcription during septation of streptomyces griseus. | streptomyces has been known to form two types of septa. the data in this research demonstrated that streptomyces griseus forms another type of septum near the base of sporogenic hyphae (basal septum). to understand the regulation of the septation machinery in s. griseus, we investigated the expression of the ftsz gene. s1 nuclease protection assays revealed that four ftsz transcripts were differentially expressed during morphological differentiation. the vegetative transcript (emanating from p(v ... | 2001 | 11489862 |
| identification of a cell wall channel of streptomyces griseus: the channel contains a binding site for streptomycin. | cells of the gram-positive actinomycete streptomyces griseus were disrupted and the cell envelope was subjected to sucrose step-gradient centrifugation. the different fractions were analysed for nadh-oxidase activity and the formation of ion-permeable channels in lipid bilayers. highest channel-forming activity and highest nadh-oxidase activity were found in different fractions. the cell wall fraction contained an ion-permeable channel with a single-channel conductance of 850 ps in 1 m kcl. the ... | 2001 | 11532134 |
| a secreted aminopeptidase of pseudomonas aeruginosa. identification, primary structure, and relationship to other aminopeptidases. | using leucine-p-nitroanilide (leu-pna) as a substrate, we demonstrated aminopeptidase activity in the culture filtrates of several pseudomonas aeruginosa strains. the aminopeptidase was partially purified by deae-cellulose chromatography and found to be heat stable. the apparent molecular mass of the enzyme was approximately 56 kda; hence, it was designated ap(56). heating (70 degrees c) of the partially purified aminopeptidase preparations led to the conversion of ap(56) to a approximately 28-k ... | 2001 | 11533066 |
| synthesis of a reported calpain inhibitor isolated from streptomyces griseus. | the reported diketopiperazine calpain inhibitor, cis-l-l-3,6-bis-(4-hydroxybenzyl)-1,4-dimethylpiperazine-2,5-dione 1, and its analogues 3 and 4 were synthesized from the corresponding amino acids. the previously assigned structure of 1 is confirmed but neither synthetic 1 nor its n-methylphenylalanine analogues 3 and 4 inhibit porcine erythrocyte calpain i. | 2001 | 11551769 |
| a complex role for the gamma-butyrolactone scb1 in regulating antibiotic production in streptomyces coelicolor a3(2). | many streptomycetes produce extracellular gamma-butyrolactones. in several cases, these have been shown to act as signals for the onset of antibiotic production. synthesis of these molecules appears to require a member of the afsa family of proteins (afsa is required for a-factor synthesis of the gamma-butyrolactone a-factor and consequently for streptomycin production in streptomyces griseus). an afsa homologue, scba, was identified in streptomyces coelicolor a3(2) and was found to lie adjacent ... | 2001 | 11555283 |
| molecular and functional analyses of the gene (esha) encoding the 52-kilodalton protein of streptomyces coelicolor a3(2) required for antibiotic production. | analysis of proteins recovered in the s100 precipitate fraction of streptomyces griseus after ultracentrifugation led to the identification of a 52-kda protein which is produced during the late growth phase. the gene (esha) which codes for this protein was cloned from s. griseus, and then its homologue was cloned from streptomyces coelicolor a3(2). the protein was deduced to be 471 amino acids in length. the protein esha is characterized by a central region that shows homology to the eukaryotic- ... | 2001 | 11567001 |
| nonactin biosynthesis: disruption of the polyketide synthase genes, nonkj, in streptomyces griseus leads to an overall 96 decrease in macrotetrolide production, yet a net increase in nonactin analogues which incorporate isobutyrate. | 2001 | 11604004 | |
| [structure and functions of bacterial proteinase precursors]. | the data on the precursors of bacterial proteases were generalized. the structure and special features of processing of the precursors of bacillary subtilisins, the alpha-lytic protease from lysobacter enzymogenes and the related chymotrypsin-like proteases from streptomyces griseus, and the metalloproteases from bacilli and pseudomonas aeruginosa were discussed. the approaches to producing the precursors and the protease propeptides and to in vitro characterizing them were particularly analyzed ... | 2001 | 11641907 |
| properties and substrate specificity of rppa, a chalcone synthase-related polyketide synthase in streptomyces griseus. | rppa, a chalcone synthase-related polyketide synthase (type iii polyketide synthase) in the bacterium streptomyces griseus, catalyzes the formation of 1,3,6,8-tetrahydroxynaphthalene (thn) from five molecules of malonyl-coa. the k(m) value for malonyl-coa and the k(cat) value for thn synthesis were determined to be 0.93 +/- 0.1 microm and 0.77 +/- 0.04 min(-1), respectively. rppa accepted aliphatic acyl-coas with the carbon lengths from c(4) to c(8) as starter substrates and catalyzed sequential ... | 2002 | 11723138 |
| atp-binding cassette transport system involved in regulation of morphological differentiation in response to glucose in streptomyces griseus. | streptomyces griseus np4, which was derived by uv mutagenesis from strain ifo13350, showed a bald and wrinkled colony morphology in response to glucose. mutant np4 formed ectopic septa at intervals along substrate hyphae, and each of the compartments developed into a spore which was indistinguishable from an aerial spore in size, shape, and thickness of the spore wall and in susceptibility to lysozyme and heat. the ectopic spores of np4 formed in liquid medium differed from "submerged spores" in ... | 2002 | 11741848 |
| bacterial degradation of natural and synthetic rubber. | the degradation of natural rubber (nr), synthetic poly(cis-1,4-isoprene) (sr), and cross-linked nr (latex gloves) by gram-positive and gram-negative bacteria was analyzed by weight loss, gel permeation chromatography, and determination of the protein content. weight losses of 11-18% and an increase in protein up to 850 microg/ml after incubation of nocardia sp. dsmz43191, streptomyces coelicolor, streptomyces griseus, bacterial isolate 18a, acinetobacter calcoaceticus, and xanthomonas sp. with l ... | 2001 | 11749186 |
| characterization of mutants defective in melanogenesis and a gene for tyrosinase of streptomyces griseus. | nitrosoguanidine-induced melanin-negative mutants of streptomyces griseus were classified according to their ability to produce streptomycin and a-factor, and to form aerial mycelium. a large proportion of the mutants showed deficiency in either antibiotic production and morphological development or both, suggesting close regulatory correlation between melanogenesis and morphological and physiological differentiation. the tyrosinase-encoding mel operon of s. griseus was cloned and examined for i ... | 2001 | 11776433 |
| the a-factor regulatory cascade and camp in the regulation of physiological and morphological development in streptomyces griseus. | in the a-factor regulatory cascade leading to the onset of streptomycin biosynthesis and aerial mycelium formation in streptomyces griseus, the a-factor receptor protein (arpa) serves as a dna-binding repressor and a-factor releases the repression by binding to arpa and dissociating it from the dna. mutants defective in arpa therefore produce streptomycin and aerial hyphae in the absence of a-factor. a gene that inhibits streptomycin production and aerial hyphae formation in an arpa mutant was c ... | 2001 | 11780789 |
| the candicidin gene cluster from streptomyces griseus imru 3570. | a 205 kb dna region from streptomyces griseus imru 3570, including the candicidin biosynthetic gene cluster, was cloned and partially sequenced. analysis of the sequenced dna led to identification of genes encoding part of a modular polyketide synthase (pks), genes for thioesterase, macrolactone ring modification, mycosamine biosynthesis and attachment to the macrolide ring, candicidin export and regulatory proteins. it represents the first extensive genetic characterization of an aromatic polye ... | 2002 | 11782498 |
| depolarization of the membrane potential by beta-lactams as a signal to induce autolysis. | the effect of beta-lactam antibiotics that are known to inhibit cell wall biosynthesis and induce cell wall autolysis on the electrophysiological state of the plasma membrane in streptomyces griseus was studied. addition of various beta-lactam antibiotics induced a dose- and growth-stage-dependent depolarization of the membrane potential of streptomyces griseus. the hydrolyzed biologically inactive derivative penicilloic acid had no depolarizing effect on the membrane potential. the ionophore gr ... | 2002 | 11811985 |
| endogenous nod-factor-like signal molecules promote early somatic embryo development in norway spruce. | embryogenic cultures of norway spruce (picea abies) are composed of pro-embryogenic masses (pems) and somatic embryos of various developmental stages. auxin is important for pem formation and proliferation. in this report we show that depletion of auxin blocks pem development and causes large-scale cell death. extracts of the media conditioned by embryogenic cultures stimulate development of pem aggregates in auxin-deficient cultures. partial characterization of the conditioning factor shows tha ... | 2002 | 11842156 |
| amfs, an extracellular peptidic morphogen in streptomyces griseus. | the amf gene cluster was previously identified as a regulator for the onset of aerial-mycelium formation in streptomyces griseus. the nucleotide sequences of amf and its counterparts in other species revealed a conserved gene organization consisting of five open reading frames. a nonsense mutation in amfs, encoding a 43-amino-acid peptide, caused significant blocking of aerial-mycelium formation and streptomycin production, suggesting its role as a regulatory molecule. extracellular-complementat ... | 2002 | 11844785 |
| intragenomic and intraspecific polymorphism of the 16s-23s rdna internally transcribed sequences of streptomyces ambofaciens. | the nucleotide composition of the internally transcribed sequences (itss) of the six rdna operons of two strains of streptomyces ambofaciens were determined. four variable and five conserved nucleotide blocks were distinguished. five different modular organizations were revealed for each strain and no homologous loci showed the same succession of blocks. this suggests that recombination frequently occurs between the rdna loci, leading to the exchange of nucleotide blocks. the modular structure w ... | 2002 | 11882697 |
| nonactin biosynthesis: the initial committed step is the condensation of acetate (malonate) and succinate. | nonactin is a macrotetrolide antibiotic produced by streptomyces griseus subsp. griseus eth a7796 that has shown activity against the p170-glycoprotein efflux pump associated with multiple drug resistant cancer cells. nonactin is a polyketide, albeit a highly atypical one. the structure is composed of two units of each of the enantiomers of nonactic acid, arranged in a macrocycle, so that the molecule has s4 symmetry and is achiral. the monomer units, (+)- and (-)-nonactic acid, are derived from ... | 2002 | 11902879 |
| indolmycin resistance of streptomyces coelicolor a3(2) by induced expression of one of its two tryptophanyl-trna synthetases. | aminoacyl-trna synthetases, a family of enzymes essential for protein synthesis, are promising targets of antimicrobials. indolmycin, a secondary metabolite of streptomyces griseus and a selective inhibitor of prokaryotic tryptophanyl-trna synthetase (trprs), was used to explore the mechanism of inhibition and to explain the resistance of a naturally occurring strain. streptomyces coelicolor a3(2), an indolmycin-resistant strain, contains two trps genes encoding distinct trprs enzymes. we show t ... | 2002 | 11970956 |
| transformation using in vivo and in vitro methylation in streptomyces griseus. | streptomyces griseus does not readily take up foreign dna isolated from other streptomyces species or escherichia coli, presumably due to its unique restriction-modification systems that function as a barrier for interspecific dna transfer. to efficiently transform s. griseus by avoiding the restriction barriers, we methylated incoming dna in vivo and in vitro and treated protoplasts with heat prior to transformation. whereas heat treatment of protoplasts or methylation of the e. coli-streptomyc ... | 2002 | 12007812 |
| identification and cloning of a type iii polyketide synthase required for diffusible pigment biosynthesis in saccharopolyspora erythraea. | the soluble, diffusible red-brown pigment produced by a saccharopolyspora erythraea "red variant" has been shown to contain glycosylated and polymerized derivatives of 2,5,7-trihydroxy-1,4-naphthoquinone (flaviolin). flaviolin is a spontaneous oxidation product of 1,3,6,8-tetrahydroxynaphthalene (thn), which is biosynthesized in bacteria by a chalcone synthase-like (cs-like) type iii polyketide synthase (pks). a fragment of the gene responsible for thn biosynthesis in s. erythraea e_8-7 was ampl ... | 2002 | 12028378 |
| cloning and analysis of the telomere and terminal inverted repeat of the linear chromosome of streptomyces griseus. | cloning and sequencing of the telomere of streptomyces griseus revealed five palindromic sequences in the terminal 116 nucleotides, all of which can make a hairpin loop structure. however, the end sequence cannot form the foldback secondary structure that is common in streptomyces telomeres and is suggested to be necessary for terminal replication. both inside ends of the terminal inverted repeat (tir) were also cloned and sequenced. the results confirmed the size of the tir to be 24 kb and iden ... | 2002 | 12029061 |
| a novel extracytoplasmic phenol oxidase of streptomyces: its possible involvement in the onset of morphogenesis. | exogenous addition of copper stimulates cellular differentiation in streptomyces spp. several lines of evidence suggested a parallel correlation between the stimulatory effect of copper and phenol-oxidizing enzyme activities in streptomyces griseus. here a novel extracytoplasmic phenol oxidase (epoa) associated with cellular development of this organism was identified and characterized. epoa activity, examined by an in-gel stain procedure with n,n'-dimethyl-p-phenylenediamine sulfate as a substr ... | 2002 | 12055296 |
| functional analysis of the chitin-binding domain of a family 19 chitinase from streptomyces griseus hut6037: substrate-binding affinity and cis-dominant increase of antifungal function. | chitinase c (chic) is the first bacterial family 19 chitinase discovered in streptomyces griseus hut6037. while it shares significant similarity with the plant family 19 chitinases in the catalytic domain, its n-terminal chitin-binding domain (chbd(chic)) differs from those of the plant enzymes. chbd(chic) and the catalytic domain (catd(chic)), as well as intact chic, were separately produced in e. coli and purified to homogeneity. binding experiments and isothermal titration calorimetry assays ... | 2002 | 12092819 |
| alteration of reaction and substrate specificity of a bacterial type iii polyketide synthase by site-directed mutagenesis. | rppa, which belongs to the type iii polyketide synthase family, catalyses the synthesis of 1,3,6,8-tetrahydroxynaphthalene (thn), which is the key intermediate of melanin biosynthesis in the bacterium streptomyces griseus. the reaction of thn synthesis catalysed by rppa is unique in the type iii polyketide synthase family, in that it selects malonyl-coa as a starter substrate. the cys-his-asn catalytic triad is also present in rppa, as in plant chalcone synthases, as revealed by analyses of acti ... | 2002 | 12139488 |
| a microbial hormone, a-factor, as a master switch for morphological differentiation and secondary metabolism in streptomyces griseus. | the gram-positive, soil-inhabiting, filamentous bacterial genus streptomyces employs gamma-butyrolactones as chemical signalling molecules or microbial hormones, together with their specific receptors, to regulate morphological and/or physiological differentiation. the a-factor regulatory cascade in streptomycin-producing streptomyces griseus commences aerial mycelium formation and production of all the secondary metabolites including streptomycin. the molecular mechanism by which a-factor trigg ... | 2002 | 12165483 |
| protein serine/threonine kinases in signal transduction for secondary metabolism and morphogenesis in streptomyces. | a number of proteins in the gram-positive bacterial genus streptomyces are phosphorylated on their serine/threonine and tyrosine residues in response to developmental phases. afsr is one of these proteins and acts as a transcriptional factor in both the regulation of secondary metabolism in streptomyces coelicolor a3(2) and morphological differentiation in streptomyces griseus. in s. coelicolor a3(2), afsr is phosphorylated on its serine and threonine residues by more than three protein kinases ... | 2002 | 12172604 |
| c-o bond formation by polyketide synthases. | polyketide synthases (pkss) assemble the polyketide carbon backbone by sequential decarboxylative condensation of acyl coenzyme a (coa) precursors, and the c-c bond-forming step in this process is catalyzed by the beta-ketoacyl synthase (ks) domain or subunit. genetic and biochemical characterization of the nonactin biosynthesis gene cluster from streptomyces griseus revealed two kss, nonj and nonk, that are highly homologous to known kss but catalyze sequential condensation of the acyl coa subs ... | 2002 | 12193782 |
| trypsin-catalysed synthesis of oligopeptide amides: comparison of catalytic efficiency among trypsins of different origin (bovine, streptomyces griseus and chum salmon). | a procedure has been developed for the synthesis of oligopeptide amide using inverse substrates as acyl donors with amino acid amide instead of p-nitroanilide as acyl acceptor and trypsins of different origin (bovine, streptomyces griseus and chum salmon trypsins) as the catalyst. the effectiveness of this procedure was demonstrated by the synthesis of a pentapeptide, boc-[leu5]-enkephalin amide, as a model compound. the method was the first enzymatic method shown to be successful at each succes ... | 2002 | 12371705 |
| identification of l-glutamine: 2-deoxy-scyllo-inosose aminotransferase required for the biosynthesis of butirosin in bacillus circulans. | using inverse pcr, two new genes (btrn and btrs) were identified upstream of the putative glycosyltransferase gene btrm in the butirosin-biosynthetic btr gene cluster of bacillus circulans. the upstream gene btrs showed significant homology with stsc of streptomyces griseus, which encodes l-glutamine:scyllo-inosose aminotransferase in the biosynthesis of streptomycin. the function of btrs was further confirmed by heterologous expression in escherichia coli and chemical identification of the conv ... | 2002 | 12374384 |
| control by a-factor of a metalloendopeptidase gene involved in aerial mycelium formation in streptomyces griseus. | in streptomyces griseus, a-factor (2-isocapryloyl-3r-hydroxymethyl-gamma-butyrolactone) switches on aerial mycelium formation and secondary metabolite biosynthesis. an a-factor-dependent transcriptional activator, adpa, activates multiple genes required for morphological development and secondary metabolism in a programmed manner. a region upstream of a zinc-containing metalloendopeptidase gene (sgma) was found among the dna fragments that had been isolated as adpa-binding sites. the primary pro ... | 2002 | 12374836 |
| effect of ph on simultaneous saccharification and isomerization by glucoamylase and glucose isomerase. | ph and temperature play critical roles in multistep enzymatic conversions. in such conversions, the optimal ph for individual steps differs greatly. in this article, we describe the production of glucoamylase (from aspergillus oryzae mtcc152 in solid-state fermentation) and glucose isomerase (from streptomyces griseus ncim2020 in submerged fermentation), used in industries for producing high-fructose syrup. optimum ph for glucoamylase was found to be 5.0. for glucose isomerase, the optimum ph ra ... | 2002 | 12396122 |
| deprogrammed sporulation in streptomyces. | the bacterial genus streptomyces forms chains of spores by septation at intervals in aerial hyphae and subsequent maturation on solid medium. substrate hyphae undergo extensive lysis, liberating nutrients on which aerial hyphae develop. some mutant strains, however, ectopically form spores by septation in substrate hyphae on solid medium or in vegetative hyphae in liquid medium, which suggests that all hyphae have the potential to differentiate into spores. a streptomyces griseus mutant strain n ... | 2002 | 12423744 |
| chitosan cross-linking with a water-soluble, blocked diisocyanate. 1. solid state. | the present investigation focuses on the synthesis and application of a cross-linking agent that is compatible with the solubility characteristics of chitosan. a water-soluble, blocked-diisocyanate was prepared as a bisulfite adduct to 1,6-hexamethylene diisocyanate, which proved to be stable for several weeks in aqueous, acidic chitosan solutions at room temperature. thermal cross-linking of chitosan as cast, dried films was investigated by varying the nco/nh(2) ratio from 0.0 to 1.2. spectrosc ... | 2002 | 12425678 |
| new and bioactive compounds from streptomyces strains residing in the wood of celastraceae. | wood from three different plants of the celastraceae growing in their natural habitats in brazil (maytenus aquifolia mart.) and south africa [putterlickia retrospinosa van wyk and mostert, p. verrucosa (e. meyer ex sonder) szyszyl.] was established as a source of endophytic bacteria using a medium selective for actinomycetes. two isolates were identified as streptomyces setonii and s. sampsonii whereas two others were not assignable to any of the known streptomyces species. they were preliminari ... | 2002 | 12430026 |
| genetic and biochemical characterization of esha, a protein that forms large multimers and affects developmental processes in streptomyces griseus. | the 52-kda protein, esha, whose expression is controlled developmentally, is produced during the late growth phase of streptomyces spp. we found that disruption of the esha gene, which encodes the esha protein, abolishes the aerial mycelium formation and streptomycin production in streptomyces griseus when grown on an agar plate. the esha disruptant ko-390 demonstrated a reduced amount of expression of the transcriptional activator strr, thus accounting for the failure to produce streptomycin. k ... | 2003 | 12488450 |
| enhanced expression of s-adenosylmethionine synthetase causes overproduction of actinorhodin in streptomyces coelicolor a3(2). | we found that a 46-kda protein is highly expressed in an actinorhodin-overproducing streptomyces coelicolor a3(2) mutant (ko-179), which exhibited a low-level resistance to streptomycin. the protein was identified as s-adenosylmethionine (sam) synthetase, which is a product of the metk gene. enzyme assay revealed that sam synthetase activity in strain ko-179 was 5- to 10-fold higher than in wild-type cells. the elevation of sam synthetase activity was found to be associated with an increase in t ... | 2003 | 12511507 |
| glutathione s-transferase isoenzymes from streptomyces griseus. | an inducible, cytosolic glutathione s-transferase (gst) was purified from streptomyces griseus. gst isoenzymes with pi values of 6.8 and 7.9 used standard gst substrates including 1-chloro-2,4-dinitrobenzene. gst had subunit and native m(r)s of 24 and 48, respectively, and the n-terminal sequence smilxywdiirglpah. | 2003 | 12514067 |
| chromosomal arm replacement in streptomyces griseus. | uv irradiation of streptomyces griseus 2247 yielded a new chromosomal deletion mutant, mm9. restriction and sequencing analysis revealed that homologous recombination between two similar lipoprotein-like open reading frames, which are located 450 and 250 kb from the left and right ends, respectively, caused chromosomal arm replacement. as a result, new 450-kb terminal inverted repeats (tirs) were formed in place of the original 24-kb tirs. frequent homologous recombinations in streptomyces strai ... | 2003 | 12533491 |
| transcriptional switch on of ssga by a-factor, which is essential for spore septum formation in streptomyces griseus. | a-factor (2-isocapryloyl-3r-hydroxymethyl-gamma-butyrolactone) triggers morphological development and secondary metabolism in streptomyces griseus. a transcriptional activator (adpa) in the a-factor regulatory cascade switches on a number of genes required for both processes. adbs11 was identified in a library of the dna fragments that are bound by adpa and mapped upstream of ssga, which is essential for septum formation in aerial hyphae. gel mobility shift assays and dnase i footprinting reveal ... | 2003 | 12562798 |
| inhibitory specificity change of the ovomucoid third domain of the silver pheasant upon introduction of an engineered cys14-cys39 bond. | the ovomucoid third domain from silver pheasant (omsvp3), a typical kazal-type inhibitor, strongly inhibits different serine proteases of various specificities, i.e., chymotrypsin, streptomyces griseus protease, subtilisin, and elastase. structural studies have suggested that conformational flexibility in the reactive site loop of the free inhibitor may be related to broad specificity of the ovomucoid. on the basis of the structural homology between omsvp3 and ascidian trypsin inhibitor (ati), w ... | 2003 | 12614146 |
| the protein complex composed of nickel-binding srnq and dna binding motif-bearing srnr of streptomyces griseus represses sodf transcription in the presence of nickel. | nickel-responsive transcriptional repression of sodf, which codes for iron- and zinc-containing superoxide dismutase of streptomyces griseus, was mediated through an operator (-2 to +15) spanning over the 5' end (+1) of the transcript. two open reading frames, srnr (12,343 da) and srnq (12,486 da), with overlapping stop-start codons were identified downstream from sodf and found responsible for the repression of sodf. the deduced amino acid sequence of srnr revealed a dna binding motif and showe ... | 2003 | 12644473 |
| molecular cloning, sequencing and expression of the gene encoding a novel chitinase a from a marine bacterium, pseudomonas sp pe2, and its domain structure. | the pcha gene encoding chitinase a (pcha) from a pythium porphyrae cell-wall-degrading marine bacterium, pseudomonas sp. pe2, was cloned and characterized. the deduced pcha was a modular enzyme composed of an n-terminal signal peptide, a glycoside hydrolase family 18 catalytic domain that was responsible for the chitinase activity, the chitin-binding domains (chbds), and the carbohydrate-binding modules (cbm). the amino acid sequence of chbd(pcha) was highly conserved in the cbm family 12 that a ... | 2003 | 12655456 |
| cloning of the conserved regulatory operon by its aerial mycelium-inducing activity in an amfr mutant of streptomyces griseus. | we report cloning and characterization of a 2.8 kb dna fragment that suppressed the aerial mycelium-deficient phenotype of an amfr mutant of streptomyces griseus when it was introduced on a high-copy-number plasmid. nucleotide sequencing revealed that the cloned dna fragment contained a part of a regulatory operon homologous to one of the conserved operons identified in the genome of streptomyces coelicolor a3(2). the operon appeared to consist of 5 cdss (rara-e; restoration of aerial mycelium f ... | 2003 | 12657469 |
| candicidin biosynthesis in streptomyces griseus. | the biosynthesis of the aromatic polyene macrolide antibiotic candicidin, produced by streptomyces griseus imru 3570, begins with a p-aminobenzoic acid (paba) molecule which is activated to paba-coa and used as starter for the head-to-tail condensation of four propionate and 14 acetate units to produce a polyketide molecule to which the deoxysugar mycosamine is attached. using the gene coding for the paba synthase ( pabab) from s. griseusimru 3570 as the probe, a 205-kb region of continuous dna ... | 2003 | 12664141 |
| use of in-biofilm expression technology to identify genes involved in pseudomonas aeruginosa biofilm development. | mature pseudomonas aeruginosa biofilms form complex three-dimensional architecture and are tolerant of antibiotics and other antimicrobial compounds. in this work, an in vivo expression technology system, originally designed to study virulence-associated genes in complex mammalian environments, was used to identify genes up-regulated in p. aeruginosa grown to a mature (5-day) biofilm. five unique cloned promoters unable to promote in vitro growth in the absence of purines after recovery from the ... | 2003 | 12700249 |
| novel chitosanase from streptomyces griseus hut 6037 with transglycosylation activity. | streptomyces griseus hut 6037 inducibly produced two chitosanases when grown on chitosan. to elucidate the mechanism of degradation of chitinous compound by this strain, chitosanases i and ii of s. griseus hut 6037 were purified and characterized. the purified enzymes had a molecular mass of 34 kda. their optimum ph was 5.7, and their optimum temperature was 60 degrees c. they hydrolyzed not only partially deacetylated chitosan, but also carboxymethylcellulose. time-dependent 1h-nmr spectra show ... | 2003 | 12728998 |
| studies on novel bacterial translocase i inhibitors, a-500359s. i. taxonomy, fermentation, isolation, physico-chemical properties and structure elucidation of a-500359 a, c, d and g. | in the course of our screening for bacterial phospho-n-acetylmuramyl-pentapeptide-translocase (translocase i: ec 2.7.8.13) inhibitors, we found inhibitory activity in the cultured broth of the strain identified as streptomyces griseus sank 60196. the strain produced capuramycin and four novel capuramycin derivatives designated as a-500359 a, c, d and g. purification and structural analysis were performed, and the structures of a-500359 a, c, d and g were elucidated as 6'''-methylcapuramycin, 3'- ... | 2003 | 12760680 |
| studies on novel bacterial translocase i inhibitors, a-500359s. iii. deaminocaprolactam derivatives of capuramycin: a-500359 e, f, h; m-1 and m-2. | novel derivatives of capuramycin were obtained when 10 mm of 2-aminoethyl-l-cysteine (aec), an inhibitor of aspartokinase, was added to the culture of streptomyces griseus sank 60196, the producer of a-500359. they were purified from the culture filtrate and their chemical structures were elucidated as a deaminocaprolactam derivative of capuramycin designated as a-500359 f, a-500359 e, a methyl ester of a-500359 f, and a-500359 h, a 3'-demethyl derivative of a-500359 f. two other compounds, a-50 ... | 2003 | 12760682 |
| studies on novel bacterial translocase i inhibitors, a-500359s. iv. biosynthesis of a-500359s. | this report describes the isolation of novel a-500359 analogues from the culture broth of streptomyces griseus sank 60196 and 13c-incorporation studies of a-500359 a to reveal the biosynthetic pathway of a-500359 derivatives. as a result, a-500359 m-3 and j were isolated as novel analogues. the former, isolated from a culture broth fed with unnatural amino acids, was a novel amino acid adduct of a-500359, and the latter was found to be a putative precursor of all a-500359 derivatives, on the bas ... | 2003 | 12760683 |
| the first semi-synthetic serine protease made by native chemical ligation. | selective incorporation of non-natural amino acid residues into proteins is a powerful approach to delineate structure-function relationships. although many methodologies are available for chemistry-based protein engineering, more facile methods are needed to make this approach suitable for routine laboratory practice. here, we describe a new strategy and provide a proof of concept for engineering semi-synthetic proteins. we chose a serine protease streptomyces griseus trypsin (sgt) for this stu ... | 2003 | 12767808 |
| characterization of season and sampling method effects on measurement of forage quality in fescue-based pastures. | information on seasonal changes and effects of sampling methods on the measurement of forage quality is limited for fescue-based pastures. eight continuously grazed, 0.76-ha, fescue-based pastures were used to compare forage type, method of collection, and seasonal effects on forage quality in a repeated-measures, split-plot design. four pastures were interseeded with red clover in march 2000. masticate (m; from four ruminally cannulated steers) and hand--clipped (c) samples were collected every ... | 2003 | 12772859 |
| classification of novel soil streptomycetes as streptomyces aureus sp. nov., streptomyces laceyi sp. nov. and streptomyces sanglieri sp. nov. | the taxonomic positions of soil isolates known as streptomyces groups a, b and c were clarified. comparative 16s rdna sequence studies indicated that representatives of all three taxa formed distinct phyletic lines within the streptomyces tree though the group a strains were shown to be related to streptomyces griseus and associated validly described species. the taxonomic integrity of all three groups was highlighted by dna:dna relatedness and ribotype data though the group a strains encompasse ... | 2003 | 12776920 |
| family 19 chitinase of streptomyces griseus hut6037 increases plant resistance to the fungal disease. | chitinase c (chic) is the first bacterial family 19 chitinase discovered in streptomyces griseus hut6037. in vitro, chic clearly inhibited hyphal extension of trichoderma reesei but a rice family 19 chitinase did not. in order to investigate the effects of chic as an increaser of plant resistance to fungal diseases, the chic gene was introduced into rice plants under the control of the increased camv 35s promoter and a signal sequence from the rice chitinase gene. transgenic plants were morpholo ... | 2003 | 12784627 |
| effect of visible light on the recovery of streptomyces griseus conidia from ultra-violet irradiation injury. | 2003 | 12790091 | |
| the large linear plasmid psla2-l of streptomyces rochei has an unusually condensed gene organization for secondary metabolism. | the complete nucleotide sequence of the large linear plasmid psla2-l in streptomyces rochei strain 7434an4 has been determined. psla2-l was found to be 210 614 bp long with a gc content of 72.8% and carries 143 open reading frames. it is especially noteworthy that three-quarters of the psla2-l dna is occupied by secondary metabolism-related genes, namely two type i polyketide synthase (pks) gene clusters for lankacidin and lankamycin, a mithramycin synthase-like type ii pks gene cluster, a carot ... | 2003 | 12791134 |