| studies on lankacidin-group (t-2636) antibiotics. ix preparation of c-labeled lankacidin c 14-propionate. | to investigate the metabolic fate of lankacidin c 14-propionate in experimental animals, the 14-c-labeled antibiotic was prepared by the fermentation of streptomyces rochei var, volubilis in the presence of various 14-c-labeled organic carboxylic acids, amino acids and carbohydrates. significant incorporation (20 similar to 40%) was observed with l-methionine-methyl-14-c. lankacidin c 14-propionate-14-c (specific activity 49.6 muci/mg) was obtained from lankacidin c-14-c and ethyl propionate by ... | 1975 | 1126865 |
| degradation of polychlorinated phenols by streptomyces rochei 303. | the strain streptomyces rochei 303 (vkm ac-1284d) is capable of utilizing 2-chloro-, 2,4-, 2,6-dichloro- and 2,4,6-trichlorophenols as the sole source of carbon. its resting cells completely dechlorinated and degraded 2-, 3-chloro-; 2,4-, 2,6-, 2,3-, 2,5-, 3,4-, 3,5-dichloro-; 2,4-, 2,6-dibromo-; 2,4,6-, 2,4,5-, 2,3,4-, 2,3,5-, 2,3,6-trichlorophenols; 2,3,5,6-tetrachloro- and pentachlorophenol. during chlorophenol degradation, a stoichiometric amount of chloride ions was released and chlorohydro ... | 1991 | 1368964 |
| butyrolactols a and b, new antifungal antibiotics. taxonomy, isolation, physico-chemical properties, structure and biological activity. | new antifungal antibiotics, butyrolactols a and b, have been isolated from the culture broth of streptomyces rochei s785-16. they are novel type of molecules containing a common 2,3-dihydroxybutyrolactone nucleus substituted with a different long hydroxyalkyl side chain. butyrolactol a showed good antifungal activity against aspergillus fumigatus and trichophyton mentagrophytes, and moderately inhibited the growth of yeasts. | 1992 | 1429230 |
| influence of aromatic substitution patterns on azo dye degradability by streptomyces spp. and phanerochaete chrysosporium. | twenty-two azo dyes were used to study the influence of substituents on azo dye biodegradability and to explore the possibility of enhancing the biodegradabilities of azo dyes without affecting their properties as dyes by changing their chemical structures. streptomyces spp. and phanerochaete chrysosporium were used in the study. none of the actinomycetes (streptomyces rochei a10, streptomyces chromofuscus a11, streptomyces diastaticus a12, s. diastaticus a13, and s. rochei a14) degraded the com ... | 1992 | 1482183 |
| cis-2-amino-1-hydroxycyclobutane-1-acetic acid, a herbicidal antimetabolite produced by streptomyces rochei a13018. | | 1991 | 1778797 |
| linear plasmids with terminal inverted repeats obtained from streptomyces rochei and kluyveromyces lactis. | linear plasmids with inverted terminal repeats of 614 bp were obtained from streptomyces rochei which produced lankacidin. the 5' ends were blocked by the association of a terminal protein. a dna model of racket frame-like structure is presented implying the juxtaposition of 2 double-stranded dnas of the same sequence through the binding of cohesive proteins which recognize and bind to the dna. two linear plasmids with the inverted terminal repeats of 202 and 184 bp were obtained from a yeast, k ... | 1985 | 2990421 |
| cloning, characterization and expression in escherichia coli of a leucine biosynthetic gene from streptomyces rochei. | leucine and histidine biosynthetic genes from streptomyces rochei hp1 that complemented auxotrophic mutations in s. lividans tk54 were cloned in pij61. dna from one leucine recombinant plasmid was subcloned into pbr322. from the latter, a recombinant plasmid was obtained that complemented the leua mutation in escherichia coli cv512 but not other leucine markers in e. coli. analysis of this and several subclones, including mutant plasmids constructed in vitro, established that the cloned s. roche ... | 1987 | 3309149 |
| interconversion of t-2636 antibiotics produced by streptomyces rochei var. volubilis. | | 1970 | 5412283 |
| studies on t-2636 antibiotics. i. taxonomy of streptomyces rochei var. volubilis var. nov. and production of the antibiotics and an esterase. | | 1971 | 5541329 |
| isolation of a streptomyces rochei idiotroph requiring beta-lysine for production of streptothricin. | | 1983 | 6319347 |
| a linear dna plasmid from streptomyces rochei with an inverted terminal repetition of 614 base pairs. | the terminal structure of a linear plasmid psla2 , which was isolated from streptomyces rochei , was analysed. the 5' ends of psla2 dna were blocked by the association of a protein probably covalently bonded with the dna. this block is removed by alkali treatment and blunt ends with 5'-phosphate and 3'-hydroxy termini were released. the two terminal fragments of psla2 were cloned and the nucleotide sequence was determined. an inverted terminal repetition of 614 bp was found along with the presen ... | 1984 | 6327287 |
| characterization and sequence analysis of a streptomyces rochei a2 endoglucanase-encoding gene. | a 7-kb fragment of streptomyces rochei a2 chromosomal dna was cloned into pat153 and shown to confer endoglucanase (egls) activity on escherichia coli cells. in e. coli clones, the egls was secreted into the periplasm. deletion analysis revealed that an 827-bp fragment was enough for the enzymatic activity. sequence analysis showed that the 827-bp fragment codes for the catalytic domain of the enzyme. the complete sequence of the gene (egls) is 1149-bp long. a signal peptide, a catalytic domain ... | 1994 | 7523249 |
| purification and characterization of 6-chlorohydroxyquinol 1,2-dioxygenase from streptomyces rochei 303: comparison with an analogous enzyme from azotobacter sp. strain gp1. | the enzyme which cleaves the benzene ring of 6-chlorohydroxyquinol was purified to apparent homogeneity from an extract of 2,4,6-trichlorophenol-grown cells of streptomyces rochei 303. like the analogous enzyme from azotobacter sp. strain gp1, it exhibited a highly restricted substrate specificity and was able to cleave only 6-chlorohydroxyquinol and hydroxyquinol and not catechol, chlorinated catechols, or pyrogallol. no extradiol-cleaving activity was observed. in contrast to 6-chlorohydroxyqu ... | 1995 | 7798136 |
| isolation and characterization of linear plasmids from lankacidin-producing streptomyces species. | streptomyces rochei 7434an4, a producer of lankacidin and lankamycin contains three large linear plasmids, psla2-l (200 kb), m (100 kb), and s (17 kb). studies on the mutants of 7434an4 having a different plasmid profile showed a parallel relationship between the presence of psla2-l and the production of both lankacidin and lankamycin. when psla2-l was transferred by protoplast fusion to s. rochei 2-39, a non-antibiotic-producing mutant of 7434an4 which contained no detectable plasmid, the fusan ... | 1994 | 7844039 |
| bidirectional replication from an internal origin in a linear streptomyces plasmid. | commonly, linear replicons that have protein covalently attached to 5' dna termini replicate by protein-primed, strand-displacing, continuous synthesis of full-length strands. the synthesis of dna in psla2, a 17-kilobase linear plasmid of streptomyces rochei containing 5' terminal protein, occurs bidirectionally from an internally located replication origin. the replication intermediates are linear duplex molecules that have recessed (approximately 280 nucleotides) 5' ends rather than full-lengt ... | 1994 | 8052852 |
| characterization of a streptomyces rochei endoglucanase. | | 1996 | 8659894 |
| streptomyces linear plasmids that contain a phage-like, centrally located, replication origin. | unlike previously studied linear replicons containing 5' dna termini covalently bound to protein, psla2, a 17 kb linear plasmid of streptomyces rochei, initiates replication internally rather than at the telomeres (chang and cohen, 1994). here we identify and characterize the replication origin of psla2, showing that it contains a series of direct repeats (iterons) within a centrally located gene encoding an essential dna-binding protein (rep1); a second essential protein (rep2), which resembles ... | 1996 | 8971702 |
| degradation of pentachlorophenol in soil by streptomyces rochei 303. | the fate of pentachlorophenol (pcp) in soil under natural conditions was investigated. it was revealed that the total amount of pcp significantly decreased when soil was inoculated by streptomyces rochei 303, a strain-destructor of chlorophenols. the products of pcp transformation, such as tetra- and trichlorophenols, pentachlorobenzene, chlorinated dioxins, were identified after the first month of the experiment. their quantity was less in the variant with the introduced strain compared to cont ... | 1997 | 9025267 |
| restriction enzyme and dna hybridization analysis of cellulolytic streptomyces isolates of different origin. | streptomyces rochei a2 endoglucanase (egls) and beta-glucosidase (bgs1) genes were used as probes to survey their distribution among 16 streptomyces strains isolated from different sources and characterized for their cellulolytic activities. the egls probe hybridized to the genomic dna of 12 strains with a restriction pattern different from that of s. rochei a2. the dna from all strains, except one, hybridized with the bgs1 probe and one strain showed the same restriction pattern as seen in s. r ... | 1997 | 9115095 |
| borrelidin is an angiogenesis inhibitor; disruption of angiogenic capillary vessels in a rat aorta matrix culture model. | borrelidin, an antibiotic from streptomyces rochei, was found to be an angiogenesis inhibitor in a rat aorta matrix culture model which forms capillary vessels in vitro. borrelidin strongly inhibited capillary tube formation with a 50%-inhibitory concentration value of 0.8 nm, and decreased the number of capillary tubes within 24 hours when added after maturation of tube formation. borrelidin remarkably disrupted capillary tubes in a dose-dependent manner, by inducing apoptosis of the tube-formi ... | 1997 | 9315080 |
| streptothricin biosynthesis is catalyzed by enzymes related to nonribosomal peptide bond formation. | in a search for strains producing biocides with a wide spectrum of activity, a new strain was isolated. this strain was taxonomically characterized as streptomyces rochei f20, and the chemical structure of the bioactive product extracted from its fermentation broth was determined to be a mixture of streptothricins. from a genomic library of the producer strain prepared in the heterologous host streptomyces lividans, a 7.2-kb dna fragment which conferred resistance to the antibiotic was isolated. ... | 1997 | 9371436 |
| a silent abc transporter isolated from streptomyces rochei f20 induces multidrug resistance. | in the search for heterologous activators for actinorhodin production in streptomyces lividans, 3.4 kb of dna from streptomyces rochei f20 (a streptothricin producer) were characterized. subcloning experiments showed that the minimal dna fragment required for activation was 0.4 kb in size. the activation is mediated by increasing the levels of transcription of the actii-orf4 gene. sequencing of the minimal activating fragment did not reveal any clues about its mechanism; nevertheless, it was sho ... | 1998 | 9696745 |
| physical mapping of the linear plasmid psla2-l and localization of the eryai and acti homologs. | the 200-kb linear plasmid psla2-l was suggested to be involved in the production of lankamycin and lankacidin in streptomyces rochei 7434an4. in this study, we have constructed a physical map for 23 psti fragments of psla2-l, the sum of which was 206 kb. detailed restriction maps for both ends of psla2-l revealed the presence of terminal inverted repeats, the size of which was found to be 2.1 kb by cloning and sequencing of the end-points. hybridization experiments using two polyketide biosynthe ... | 1998 | 9836424 |
| new ravidomycin analogues, fe35a and fe35b, apoptosis inducers produced by streptomyces rochei. | | 1998 | 10048570 |
| optimisation of cultural conditions for antifungal antibiotic accumulation by streptomyces rochei g164. | to induce higher amount of antifungal antibiotic production by variation of cultural parameters has been studied. the maximum effectivity was found in sucrose as carbon source, peptone as nitrogen source and at ph 7.0. the effect of other selected factors were also evaluated in order to judge the variables that influenced antibiotic production. | 1997 | 10386018 |
| establishment of a quantitative mouse dorsal air sac model and its application to evaluate a new angiogenesis inhibitor. | we have developed an improved mouse dorsal air sac model for quantifying in vivo tumor-induced angiogenesis. in our improved model, tumor angiogenesis is determined by measuring the blood volume in an area of skin held in contact with a tumor cell-containing chamber, using 51cr-labeled red blood cells (rbc). the blood volume induced by murine b16-bl6 melanoma cells increased linearly with the cell number in the range from 2 x 10(5) to 5 x 10(6). ten of 11 human tumor cell lines examined induced ... | 1999 | 10757446 |
| identification of two polyketide synthase gene clusters on the linear plasmid psla2-l in streptomyces rochei. | the 200kb linear plasmid psla2-l was suggested to be involved in the production of two macrolide antibiotics, lankamycin (lm) and lankacidin (lc), in streptomyces rochei 7434an4. hybridization experiments with the polyketide synthase (pks) genes for erythromycin and actinorhodin identified two eryai-homologous regions and an acti-homologous region on psla2-l. the nucleotide sequence of a 3.6kb saci fragment carrying one of the eryai-homologs revealed that it codes for part of a large protein wit ... | 2000 | 10767533 |
| cloning and analysis of the replication origin and the telomeres of the large linear plasmid psla2-l in streptomyces rochei. | the replication origin and both terminal segments were cloned from the large linear plasmid psla2-l in streptomyces rochei 7434an4. the basic replicon consists of a 1.9-kb dna fragment, which contains the genetic information required for autonomous replication in circular form. sequence analysis revealed two orfs, repl1 and repl2, with no similarity to any of the replication initiator proteins in the database. deletion and mutational analysis showed that repl1 is essential for replication and re ... | 2000 | 10954087 |
| terminal proteins essential for the replication of linear plasmids and chromosomes in streptomyces. | linear plasmids and chromosomes of the bacterial genus streptomyces have proteins of unknown characteristics and function linked covalently to their 5' dna termini. we purified protein attached to the end of the psla2 linear plasmid of streptomyces rochei, determined the n-terminal amino acid sequence, and used this information to clone corresponding genes from a s. rochei cosmid library. three separate terminal protein genes (here designated as tpgr1, tpgr2, and tpgr3), which map to the s. roch ... | 2001 | 11410532 |
| cloning and expression of an endocellulase gene from a novel streptomycete isolated from an east african soda lake. | alkaline cellulase-producing actinomycete strains were isolated from mud samples collected from east african soda lakes. the strains were identified as novel streptomyces spp. by 16s rdna sequence analysis. a cellulase gene (cel12a) from streptomyces sp. strain 11ag8 was cloned by expression screening of a genomic dna library in escherichia coli. from the nucleotide sequence of a 1.5-kb dna fragment, an open reading frame of 1,113 nucleotides was identified encoding a protein of 371 amino acids. ... | 2001 | 11699647 |
| purification and characterization of beta-1,6-glucanase of streptomyces rochei application in the study of yeast cell wall proteins. | a beta-1,6-glucanase was purified to apparent homogeneity from a commercial yeast digestive enzyme prepared from streptomyces rochei by a series of column chromatographies. the molecular mass of the purified enzyme was 60 kda by sds-page. the purified enzyme had an optimum ph range from 4.0 to 6.0 and was stable in the same ph range. the enzyme was stable under 50 degrees c but lost almost all activity at 60 degrees c. the enzyme was specific to beta-1,6-glucan and had little activity towards be ... | 2002 | 12507000 |
| 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 |
| growth phase-dependent expression of an endoglucanase encoding gene (egls) in streptomyces rochei a2. | different growth phases of streptomyces rochei a2, a cellulolytic strain isolated from termite gut, were determined in liquid culture. the strain exhibited a multiphasic growth curve typical of streptomycetes. in s. rochei a2, the secreted endoglucanase egls is coded by a tta-containing gene, conserved in other streptomyces. the onset of s. rochei a2 egls gene expression was determined by rt-pcr using total rna extracted at different growth phases. the egls gene was expressed only during transit ... | 2004 | 15321672 |
| in situ monitoring of streptothricin production by streptomyces rochei f20 in soil and rhizosphere. | the onset of streptothricin (st) biosynthesis in streptomyces rochei f20 was studied by using reverse transcription-pcr (rt-pcr) to detect transcripts of st genes during growth in liquid medium, soil, and the rhizosphere. in situ results correlated with those obtained in vitro, illustrating the growth phase-dependent manner of st production by f20. maximal transcription of st resistance (sttr) and biosynthesis (stta) genes occurred during the transition between the exponential and stationary pha ... | 2004 | 15345403 |
| isolation and characterization of mesophilic, oxalate-degrading streptomyces from plant rhizosphere and forest soils. | the present work was aimed at the isolation of additional new pure cultures of oxalate-degrading streptomyces and its preliminary characterization for further work in the field of oxalate metabolism and taxonomic studies. mesophilic, oxalate-degrading streptomyces were enriched and isolated from plant rhizosphere and forest soil samples. strains were examined for cultural, morphological (spore chain morphology, spore mass colour, diffusible and melanin pigment production), physiological (antibio ... | 2004 | 15448922 |
| cyclization mechanism for the synthesis of macrocyclic antibiotic lankacidin in streptomyces rochei. | the lankacidin biosynthetic gene cluster in streptomyces rochei strain 7434an4 was found to span 31 kb of the giant linear plasmid psla2-l and contain a polyketide synthase (pks)/nonribosomal peptide synthetase (nrps) hybrid gene (lkca), type i pks genes, and pyrroloquinoline quinone (pqq) biosynthetic genes (lkck-lkco). feeding of pqq to a pqq mutant restored the lankacidin production, suggesting its crucial role in an oxidation process. however, formation of the 17-membered macrocyclic ring wa ... | 2005 | 15734652 |
| production of a growth dependent metabolite active against dermatophytes by streptomyces rochei ak 39. | dermatophytes responsible for causing dermatophytoses in humans have acquired resistance to certain antimycotic drugs. we isolated naturally occurring actinomycetes with an ability to produce metabolites having antimycotic property. the timecourse of antifungal metabolite production in terms of arbitrary units (au) under optimum conditions was studied. | 2005 | 15802758 |
| prediction and functional analysis of the replication origin of the linear plasmid pscl2 in streptomyces clavuligerus. | pscl2 (120 kb), one of the linear plasmids found in streptomyces clavuligerus nrrl3585, was isolated and partially sequenced. computational analysis of the central region of pscl2 revealed the presence of two open reading frames that appear to encode proteins highly homologous to repl1 and repl2, replication proteins from psla2-l, the large linear plasmid in streptomyces rochei. the s. clavuligerus open reading frames were designated repc1 and repc2, encoding the proteins repc1 (150 amino acids) ... | 2006 | 16699579 |
| analysis of the loading and hydroxylation steps in lankamycin biosynthesis in streptomyces rochei. | the biosynthetic gene cluster of lankamycin (lm), a 14-member macrolide antibiotic, is encoded on the 210-kb linear plasmid psla2-l in streptomyces rochei 7434an4. lm contains a 3-hydroxy-2-butyl group at the c-13 position, which is different from an ethyl group in erythromycin. the following two possibilities could be considered for the origin of this starter moiety of lm biosynthesis: (i) an extra module exists in the biosynthetic gene cluster and loads an additional acetate molecule, or (ii) ... | 2006 | 16723550 |
| gamma-butyrolactone autoregulator-receptor system involved in lankacidin and lankamycin production and morphological differentiation in streptomyces rochei. | an afsa homologue (srrx) and three gamma-butyrolactone receptor gene homologues (srra, srrb and srrc) are coded on the giant linear plasmid psla2-l in streptomyces rochei 7434an4, a producer of two polyketide antibiotics, lankacidin and lankamycin. construction of gene disruptants and their phenotypic study revealed that srrx and srra make a gamma-butyrolactone receptor system in this strain. addition of a gamma-butyrolactone fraction to an srrx-deficient mutant restored the production of lankac ... | 2007 | 17526839 |
| an improved chemo-enzymatic synthesis of 1-beta-o-acyl glucuronides: highly chemoselective enzymatic removal of protecting groups from corresponding methyl acetyl derivatives. | an improved and widely applicable chemo-enzymatic method for the synthesis of a series of 1-beta-o-acyl glucuronides 5a-f has been developed from the corresponding methyl acetyl derivatives 3a-f, which were stereospecifically synthesized from cesium salts of carboxylic acids 1a-f and methyl 2,3,4-tri-o-acetyl-1-bromo-1-deoxy-alpha-d-glucopyranuronate (2). chemoselectivity of lipase as amano (las) in the hydrolytic removal of o-acetyl groups of 3a-f to provide methyl esters 4a-f was influenced by ... | 2007 | 17985922 |
| analysis of modular-iterative mixed biosynthesis of lankacidin by heterologous expression and gene fusion. | lankacidin is a unique 17-membered macrocyclic antibiotic different from usual even-membered macrolides. based on the gene organization of the lankacidin biosynthetic cluster coded on the linear plasmid psla2-l in streptomyces rochei, we previously proposed a hypothesis of modular-iterative mixed polyketide biosynthesis for lankacidin. two experimental evidences in this paper further strengthened this hypothesis. heterologous expression of the lankacidin cluster (lkca-lkco) in streptomyces livid ... | 2007 | 18057700 |
| gamma-butyrolactone-dependent expression of the streptomyces antibiotic regulatory protein gene srry plays a central role in the regulatory cascade leading to lankacidin and lankamycin production in streptomyces rochei. | our previous studies revealed that the srrx and srra genes carried on the large linear plasmid psla2-l constitute a gamma-butyrolactone-receptor system in streptomyces rochei. extensive transcriptional analysis has now showed that the streptomyces antibiotic regulatory protein gene srry, which is also carried on psla2-l, is a target of the receptor/repressor srra and plays a central role in lankacidin and lankamycin production. the srry gene was expressed in a growth-dependent manner, slightly p ... | 2008 | 18083808 |
| [identification of endophytic actinomycete lj20 from plant and its antifungal substances]. | endophytic actinomycete lj20 with antifungal activity was isolated from the roots of capsicum plants. we identified lj20 and synthesized its antifungal substances. | 2008 | 18837367 |
| extensive mutational analysis of modular-iterative mixed polyketide biosynthesis of lankacidin in streptomyces rochei. | extensive mutations of lankacidin synthase genes were carried out to analyze the modular-iterative mixed polyketide biosynthesis of lankacidin. three ketoreductase domains (lkcc-kr, lkcf-kr1, and lkcf-kr2) were inactivated by in-frame deletion and site-directed mutagenesis of their active sites. the mutants ceased or diminished lankacidin production, indicating that the three kr domains are functional in lankacidin biosynthesis. however, all of the kr mutants failed to accumulate the expected un ... | 2009 | 19966473 |
| the structure of ribosome-lankacidin complex reveals ribosomal sites for synergistic antibiotics. | crystallographic analysis revealed that the 17-member polyketide antibiotic lankacidin produced by streptomyces rochei binds at the peptidyl transferase center of the eubacterial large ribosomal subunit. biochemical and functional studies verified this finding and showed interference with peptide bond formation. chemical probing indicated that the macrolide lankamycin, a second antibiotic produced by the same species, binds at a neighboring site, at the ribosome exit tunnel. these two antibiotic ... | 2010 | 20080686 |
| regulation of lankamycin biosynthesis in streptomyces rochei by two sarp genes, srry and srrz. | transcription and complementation experiments were carried out to analyze the regulatory hierarchy of two streptomyces antibiotic regulatory protein (sarp) genes, srry and srrz, in the gamma-butyrolactone (gb)-dependent regulatory cascade in streptomyces rochei 7434an4. the srry gene was transcribed in the srrz mutant, while the srrz gene was not in the srry mutant. the srry protein was specifically bound to the promoter region of srrz, where a possible sarp binding sequence was identified 26 bp ... | 2010 | 20378964 |
| [isolation, identification and insecticidal activity of endophyte from achnatherum inebrians]. | to study endophyte species of achnatherum inebrians and to screen strains with insecticidal activity against cotton insect. | 2010 | 20560358 |
| bioremediation of pah by streptomyces sp. | an actinobacterium designated as pah-13 was isolated from bitumen (heavy crude oil) soil collected from mathura refinery, india. the isolate was screened for its ability to degrade 3-4 ring pah compounds (anthracene, fluorene, phenanthrene and pyrene) in minimal medium supplemented with 0.1% yeast extract as a co-substrate. the isolate was found to degrade four pahs between 28%-92% within 15 days at 100 ppm level. in addition, the strain showed good extracellular production of biosurfactant meas ... | 2011 | 21301805 |
| psla2-m of streptomyces rochei is a composite linear plasmid characterized by self-defense genes and homology with psla2-l. | the 113,463-bp nucleotide sequence of the linear plasmid psla2-m of streptomyces rochei 7434an4 was determined. psla2-m had a 69.7% overall gc content, 352-bp terminal inverted repeats with 91% (321/352) identity at both ends, and 121 open reading frames. the rightmost 14.6-kb sequence was almost (14,550/14,555) identical to that of the coexisting 211-kb linear plasmid psla2-l. adjacent to this homologous region an 11.8-kb crispr cluster was identified, which is known to function against phage i ... | 2011 | 21670526 |
| streptomyces rochei acta1551, an indigenous greek isolate studied as a potential biocontrol agent against fusarium oxysporum f.sp. lycopersici. | many studies have shown that several greek ecosystems inhabit very interesting bacteria with biotechnological properties. therefore streptomyces isolates from diverse greek habitats were selected for their antifungal activity against the common phytopathogenic fungus fusarium oxysporum. the isolate encoded acta1551, member of streptomyces genus, could strongly suppress the fungal growth when examined in antagonistic bioassays in vitro. the isolate was found phylogenetically relative to streptomy ... | 2013 | 23762841 |
| characterization of a potential β-lactamase inhibitory metabolite from a marine streptomyces sp. pm49 active against multidrug-resistant pathogens. | actinobacteria is a prolific producer of complex natural products; we isolated a potential marine streptomyces sp. pm49 strain from bay of bengal coastal area of india. the strain pm49 exhibited highly efficient antibacterial properties on multidrug-resistant pathogens with a zone of inhibition of 14-17 mm. ssf was adopted for the production of the secondary metabolites from pm49 with isp2; utilizing agricultural wastes for compound extraction was also attempted. bioactive fraction of rf value 0 ... | 2015 | 25737024 |
| complementary and synergistic roles in enzyme-catalyzed regioselective and complete hydrolytic deprotection of o-acetylated β-d-glucopyranosides of n-arylacetohydroxamic acids. | an efficient chemoenzymatic synthesis of β-d-glucopyranosides of n-arylacetohydroxamic acids 3a-c was achieved by the chemoselective o-deacetylation of 1a-c under mild, neutral conditions, with no accompanying n-deacetylation. lipase as amano from aspergillus niger (las) and carboxylesterase from streptomyces rochei (csr) played complementary, synergistic roles in the o-deacetylation of 1a and its partially o-deacetylated intermediates. an intramolecular o-acetyl migration, which proceeded simul ... | 2012 | 22283641 |
| screening of endophytic streptomycetes isolated from parthenium hysterophorus l. against nosocomial pathogens. | parthenium hysterophorus l. is an obnoxious weed of the family asteraceae recognized for its detrimental effects and significant economic losses to agriculture. in this study 42 endophytic streptomycetes strains were isolated from its roots and leaves. the isolates were identified by morphological, microscopic, biochemical and physiological characterization as members of genus streptomyces. in 16s rrna gene sequencing the selected isolates exhibited maximum similarity with streptomyces rochei (9 ... | 2013 | 23455197 |
| terpenoid bioactive compound from streptomyces rochei (m32): taxonomy, fermentation and biological activities. | the present study emphasized the production of biologically active terpenoid compound from streptomyces rochei m32, which was isolated from western ghats ecosystem, south india. the presence of resistant genes like meca, vana of staphylococcus aureus and bla shv, bla tem of pseudomonas aeruginosa was confirmed by molecular studies. the isolated compound from streptomyces rochei m32 inhibited wide range of standard and clinical drug resistant pathogens and enteric pathogens. the rice bran supplem ... | 2016 | 27562595 |
| endophytic actinomycetes from spontaneous plants of algerian sahara: indole-3-acetic acid production and tomato plants growth promoting activity. | twenty-seven endophytic actinomycete strains were isolated from five spontaneous plants well adapted to the poor sandy soil and arid climatic conditions of the algerian sahara. morphological and chemotaxonomical analysis indicated that twenty-two isolates belonged to the streptomyces genus and the remaining five were non-streptomyces. all endophytic strains were screened for their ability to produce indole-3-acetic acid (iaa) in vitro on a chemically defined medium. eighteen strains were able to ... | 2013 | 23579766 |
| enhanced biodegradation of pahs by microbial consortium with different amendment and their fate in in-situ condition. | microbial degradation is a useful tool to prevent chemical pollution in soil. in the present study, in-situ bioremediation of polyaromatic hydrocarbons (pahs) by microbial consortium consisting of serratia marcescens l-11, streptomyces rochei pah-13 and phanerochaete chrysosporium vv-18 has been reported. in preliminary studies, the consortium degraded nearly 60-70% of pahs in broth within 7 days under controlled conditions. the same consortium was evaluated for its competence under natural cond ... | 2016 | 27558829 |
| plant growth promoting potential and soil enzyme production of the most abundant streptomyces spp. from wheat rhizosphere. | to evaluate the plant growth promotion (pgp) potential and soil enzyme production under solid state fermentation (ssf) by most abundant streptomyces spp. isolated from the wheat rhizosphere and to evaluate their effect on plant growth parameters. | 2012 | 22849825 |
| taxonomy and polyphasic characterization of alkaline amylase producing marine actinomycete streptomyces rochei btss 1001. | actinomycetes isolated from marine sediments along the southeast coast of bay of bengal were investigated for amylolytic activity. marine actinomycete btss 1001 producing an alkaline amylase was identified from marine sediment of diviseema coast, bay of bengal. the isolate produced alkaline amylase with maximum amylolytic activity at ph 9.5 at 50°c. the organism produced white to pale grey substrate mycelium and grayish aerial mycelium with pinkish brown pigmentation. a comprehensive study of mo ... | 2013 | 24489548 |
| functional genome mining for metabolites encoded by large gene clusters through heterologous expression of a whole-genome bacterial artificial chromosome library in streptomyces spp. | genome sequencing projects in the last decade revealed numerous cryptic biosynthetic pathways for unknown secondary metabolites in microbes, revitalizing drug discovery from microbial metabolites by approaches called genome mining. in this work, we developed a heterologous expression and functional screening approach for genome mining from genomic bacterial artificial chromosome (bac) libraries in streptomyces spp. we demonstrate mining from a strain of streptomyces rochei, which is known to pro ... | 2016 | 27451447 |
| isolation and biosynthesis of an azoxyalkene compound produced by a multiple gene disruptant of streptomyces rochei. | streptomyces rochei 7434an4 predominantly produces lankacidin and lankamycin under normal culture conditions, thus suggesting that other biosynthetic gene clusters for secondary metabolites are silent. to identify the silent metabolites of 7434an4, we constructed mutant ka57 with multiple disruptions of the transcriptional repressor srrb and the biosynthesis genes for both antibiotics. ka57 accumulated a compound (ka57a) with a strong uv absorption at 235 nm, not detected in the parent strain or ... | 2015 | 26300120 |
| cytosine-type nucleosides from marine-derived streptomyces rochei 06cm016. | rocheicoside a (3), a nucleoside analog possessing a novel 5-(hydroxymethyl)-5-methylimidazolidin-4-one substructure, was isolated from marine-derived actinomycete streptomyces rochei 06cm016, together with a new (4) and three known compounds. structures of the new metabolites were elucidated by one-dimensional ((1)h and (13)c) and 2d nmr (cosy, hmqc and hmbc) and hr-tof-ms analyses. all the metabolites exhibited significant antimicrobial activity. a plausible mechanism was proposed for compound ... | 2016 | 26126744 |
| the tap-tpg gene pair on the linear plasmid functions to maintain a linear topology of the chromosome in streptomyces rochei. | streptomyces rochei 7434an4 carries three linear plasmids, psla2-l (211 kb), psla2-m (113 kb) and psla2-s (18 kb), their complete nucleotide sequences having been determined. restriction and sequencing analysis revealed that the telomere sequences at both ends of the linear chromosome are identical to each other, are 98.5% identical to the right end sequences of psla2-l and psla2-m up to 3.1 kb from the ends and have homology to those of typical streptomyces species. mutant 2-39, which lost all ... | 2015 | 25495952 |
| blockage of the early step of lankacidin biosynthesis caused a large production of pentamycin, citreodiol and epi-citreodiol in streptomyces rochei. | in our effort to find the key intermediates of lankacidin biosynthesis in streptomyces rochei, three uv-active compounds were isolated from mutant fs18, a gene disruptant of lkca encoding a non-ribosomal peptide synthetase (nrps)-polyketide synthase (pks) hybrid enzyme. their structures were elucidated on the basis of spectroscopic data of nmr and ms. two compounds of a higher mobile spot on silica gel tlc (rf=0.45 in chcl3-meoh=20:1) were determined to be an epimeric mixture of citreodiol and e ... | 2015 | 25464973 |
| genetic and biochemical analysis of the antibiotic biosynthetic gene clusters on the streptomyces linear plasmid. | we extensively analyzed the giant linear plasmid psla2-l in streptomyces rochei 7434an4, a producer of two structurally unrelated polyketide antibiotics, lankacidin and lankamycin. it was found that amine oxidase lkce oxidizes an acyclic amine to an imine, which is in turn converted to the 17-membered carbocyclic lankacidin. heterologous expression and translational fusion experiments indicated the modular-iterative mixed polyketide biosynthesis of lankacidin. concerning to lankamycin biosynthes ... | 2014 | 25036669 |
| the butenolide signaling molecules srb1 and srb2 induce lankacidin and lankamycin production in streptomyces rochei. | new signaling molecules that induce lankacidin and lankamycin production in streptomyces rochei were extracted from the culture filtrate and purified by sephadex lh20 and silica gel chromatography with the help of bioassay. chiral hplc and esi-ms analyses indicated the presence of two active components--srb1 and srb2--and their molecular formulas were established to be c15h24o5 and c16h26o5, respectively. by extensive nmr analysis, srb1 and srb2 were determined to be 2-(1'-hydroxy-6'-oxo-8'-meth ... | 2012 | 22761035 |
| screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes. | actinomycetes from earthworm castings were isolated and screened for their antimicrobial activity and industrial enzymes. a total of 48 isolates were obtained from 12 samples of earthworm castings. highest numbers of isolates were recovered from forest site (58.33 %) as compared to grassland (25%) and agricultural land (16.66%). the growth patterns, mycelial coloration of abundance actinomycetes were documented. the dominant genera identified by cultural, morphological and physiological characte ... | 2012 | 24031819 |