An antibiotic complex produced byStreptomyces werraensis 1365T

An antibiotic complex comprising four components (A, B, C, and X) was extracted from a native solution and myceliumof Streptomyces werraensis 1365T. The components were purified by column and thinlayer (TLC) Chromatographic procedures to study their physicochemical and biological properties. The results were used to identify the substances isolated. The preliminary data allowed us to identify the components X, A, and B as the previously described compounds undecylprodigiosin, anisomycin, and copiamycin, respectively, whereas component C is a natural compound which has probably never been described.     

Structure of heliomycin produced by Streptomyces heliomycini and antibiotic 11-98 produced by Streptomyces olivocinereus

The data on UV, 1H NMR and mass spectroscopy confirmed that heliomycin produced by S. heliomycini and antibiotic 11-98 produced by S. olivocinereus were identical with resistomycin. The major minor component produced by S. heliomycini was shown to be resistoflavin which was also confirmed by physicochemical methods.     

Isolation and characterization of an antibiotic produced by the scab disease-suppressive Streptomyces diastatochromogenes strain PonSSII

An antibiotic produced by the scab disease-suppressive Streptomyces diastatochromogenes strain PonSSII has been isolated and partially characterized. The antibiotic is produced throughout culture growth, with maximum amounts accumulating in the broth when the culture is in the early stationary phase of growth. The activity declines within about 30 h after the culture enters stationary phase. Purification techniques included chromatography on Amberlite XAD-2, DEAE Sephadex and SP Sephadex in addition to C18 HPLC with an average yield of 75%. This antibiotic only inhibits pathogenic strains of S. scabies that cause scab disease on potato and other tuberous vegetables and does not affect S. griseus, S. venezuelae, Actinomyces bovis, Nocardia asteroides, Clostridium perfringens, Bacillus subtilis, Staphylococcus aureus, S. epidermidis, Enterococcus faecalis, Micrococcus luteus, Serratia marcescens and Escherichia coli. The antibiotic has a molecular weight of 500 or less, and is stable for weeks at acidic pH but is very labile at alkaline pH conditions. Received 18 February 1997/ Accepted in revised form 11 August 1997     

Determination of the structure of the main component of an antibiotic complex produced by Streptomyces griseolus 182]

In the programme for screening antibiotics with antifungal and immunosuppressing activity a culture of Streptomyces griseolus 182 was isolated. The culture produced a complex of oligomycin structure antibiotics. Individual components of the complex were isolated by HPLC. The complex was shown to contain three components at a ratio of 80:15:5. The findings were compared with the physico-chemical characteristics of the described antibiotics. On the basis of the analysis it was concluded that fraction 2 of the antibiotic complex 182 could be oligomycin A. A detailed comparative investigation of oligomycin A and component 2 with HPLC, FMR, IR spectroscopy and mass spectrometry revealed their identity. The other two components were shown to be oligomycins B and C.     

Development of a new method for preparing biologically active compounds based on the typed strain Streptomyces werraensis

The regulatory function of a DNA fragment responsible for actinomycin resistance in the typed strain Streptomyces werraensis ATCC 1365, which produces a macrotetrolide antibiotic, was studied. Metabolic changes made this strain capable of producing an antibiotic complex, which comprises four biologically active compounds absent from the parent culture.     

An ammonium sulfate sensitive endoxylanase produced by Streptomyces

Streptomyces sp. CSWu2 was newly isolated and identified from Korean soil. In culture medium, the strain produced a highly active endoxylanase (Xynwu2), which was purified to homogeneity by a single-step chromatography on Poros-HQ. The xylanase was ~38 kDa and its activity was maximal at 65 °C and pH 11.0. It was stable up to 60 °C and from pH 8.0 to 12.0, and its activity was slightly enhanced by nonionic detergents, but inhibited by EDTA, EGTA, and divalent metal ions. Intriguingly, Xynwu2 was highly sensitive to ammonium sulfate, but its completely suppressed activity was recovered by desalting out. Xynwu2 produced xylose and xylobiose as principal end products from xylan, suggesting an endoxylanase nature. Importantly, scanning electron microscopy showed Xynwu2 efficiently degraded corncobs, an agro-industrial waste material. We believe that Xynwu2 is a potential candidate for converting lignocellulosic waste material into simple sugars which could be used to produce bioethanol and other value-added products.     

Biosynthetic studies on saframycin A, a quinone antitumor antibiotic produced by Streptomyces lavendulae

The biosynthesis of saframycin A, a heterocyclic quinone antitumor antibiotic isolated from Streptomyces lavendulae 314, was studied by feeding experiments with 14C and 13C precursors. Highly increased production of saframycin A and prolongation of the maximum production period of saframycin A were attained by constant pH control of the culture and by addition of chloramphenicol to the culture. The biosynthetic origin of the quinone skeleton common to the saframycin group was confirmed to be two tyrosine molecules which condense to generate the basic ring system of saframycin A. Feeding experiments with [1-13C]tyrosine showed specific labeling of C-11 and C-21 carbons of saframycin A, and the enrichment of the carbons was 40-fold over natural abundance. Two O- and two C-methyl and one N-methyl carbons arose directly from methionine, and alanine and glycine were the precursors for the pyruvoyl amide side chain of saframycin A.     

Phylogenetics of an antibiotic producing Streptomyces strain isolated from soil

Traditional methods of species classification and identification of the organism are based on morphological, physiological, biochemical, developmental and nutritional characteristics. Accurate assignment of taxonomic status to the new biologically active microbial isolates through existing bioinformatics methods is now very essential and also helpful in chemical characterization of the active molecule produced by microorganisms. The bacterial strain M4 (ckm7) was isolated from the pre-treated soil sample collected from the agricultural field of Eastern Uttar Pradesh (U.P.), India and was found to be producing antibacterial and antifungal antibiotics. Taxonomic identification of the isolate belongs to the genus Streptomyces which was done with the help of sequence analysis and later confirmed by biological activity. Sequence comparison study of ckm7 showed 98% identical similarity with 16S rRNA gene sequences of Streptomyces spinichromogenes, Streptomyces triostinicus and Streptomyces capoamus. On the basis of both biological activity and phylogenetic analysis of ckm7, it was concluded that the isolated strain is a new variant of S. triostinicus.     

Ester antibiotic accumulation by Streptomyces hygroscopicus

In an attempt to maximize the ester antibiotic production by Streptomyces hygroscopicus D1.5, its efficacy was found to be enhanced by manipulation of the nutrient and physical environment. The two stage fermentation using seed inoculum (10% v/v) resulted in better production while fermentation continued for 5 days in pH 7.0 at 30 degrees C. Enhanced yield was also observed in whole cell immobilization. Under entrapment, maximum yield was achieved at 7th and 9th day of fermentation for mycelia and spore. In addition, the beads could be reused up to the 3rd cycle.