Metabolites ofStreptomyces noursei

Было установлено, что актиномицет Str. noursei образует амиды некоторых разветвленных алифатических кислот: изобутирамид, метилэтилацетамид, изовалерамид, а, вероятно, и более сложные гомологи, как изокапронамид, изоэнантамид и 4-метилкапронамид. Обсуждается биогенез этих веществ.     

Metabolites ofStreptomyces noursei

Production of cycloheximide and fungicidin by the producing strainStreptomyces noursei 52/152 was shown to be coupled. Cycloheximide added to the culture medium increased the production of fungicidin, addition of fungicidin caused an increase of the production of cycloheximide. Antibiotic compounds added were degraded in the course of cultivation approximately to the same amount as if produced in control cultures. Cycloheximide added to the culture medium was not transformed to actiphenol. It was suggested that the synthesis of secondary metabolites ofStreptomyces noursei is controlled by mechanisms analogous to repression or allosteric inhibition.     

Metabolites ofStreptomyces noursei

The production variability of secondary metabolites was studied after treatment with mutagenic factors. 852 isolates were examined, out of which 308 after X-irradiation, 277 after u. v.—irradiation and 267 after treatment with nitrogen mustard. According to the production of individual secondary metabolites examined it was possible to divide the strains obtained into 4 groups.     

Metabolites ofStreptomyces noursei

Branched chain amino acids are degraded byStreptomyces noursei to the corresponding amides: valine being the precursor of isobutyramide, leucine of isovaleramide and isoleucine of anteisovaleramide. The formation of amides is pyridoxalphosphate dependent and is catalyzed by peroxidase. Furthermore it was found that branched chain amino acids were also degraded via the corresponding 2-oxoacids into acylCoA which can be dehydrogenated to unsaturated acylCoA or hydrolyzed to acids and CoASH.     

Metabolites ofStreptomyces noursei

The antibiotic cycloheximide is formed biogenetically from six malonate units, five of which undergo decarboxylation, both methyl groups are of methionine origin. The biogenesis of the glutarimide part of the molecule is nonstereospecific. Degradation procedures using¹⁴C-labelled substrates are described.     

The metabolism ofStreptomyces griseus

The electron transfer pathway in the respiratory particles ofStreptomyces griseus was studied. Vitamins K₃ and K₅,α- andβ-naphthoquinones, served as the hydrogen acceptors in succinate oxidation, and succinate- and reduced nicotinamide adenine dinucleotide (NADH)-cytochromec reductase activities, but were ineffective for NADH oxidase activity. Vitamin K seemed to mediate the hydrogen from NADH-diaphorase to cytochromec. Chlorpromazine inhibited electron transfer in the respiratory particles. Cyanide completely inhibited the electron transfer system initially, however, oxygen consumption increased gradually with time. AlthoughS. griseus possesses cytochromesa, b, c and pigment 625 (probablyd), the electron transfer chain was complicated. Two terminal oxidase activities (cytochromec oxidase and cytochromec peroxidase activities) were detected in the respiratory particles ofS. griseus. Dedicated to Prof. Shoichiro Usami celebrating his sexagenary birthday.     

Identification ofStreptomyces odor spectrum

The chemical composition of odors produced by nine strains ofStreptomyces was determined. StrainsStreptomyces aureofaciens, S. avermitilis, S. cinamomensis, S. coelicolor, S. griseus, S. lividans, S. rimosus, S. spectabilis, S. virginiae (as representatives of producers of biologically active compounds) were cultivated at the same time statically in dishes and in shaken flasks at similar cultivation conditions. According to the GC-MS analysis of odor compounds, more than twenty noteworthy volatile chemical individuals were identified. As the main component of odor spectrum geosmin and homologues of oxolones (dihydrofuranones) were found; the other compounds (pyrazine derivatives, acetoin and its homologues, aromatic esters, furan derivatives,etc.) were in minority. An erratum to this article is available at .     

Mutant strains ofStreptomyces cinnamonensis protoplasts

Mycelium of Streptomyces cinnamonensis mutant strains cultivated in a synthetic medium with glycine produced protoplasts after lysis of cell walls with lysozyme. The protoplast yield was up to 95%. The protoplasts could revert and mycelial forms were thus regenerated. In a sucrose-containing medium the protoplasts stored at 4 degrees C were stable for 2 d.     

Properties of chorismate mutase ofStreptomyces venezuelae

Zusammenfassung Aus Kulturen von Streptomyces collinus (Stamm Tü 365) wurde ein neues, gelbes Antibioticum isoliert und durch analytische, spektroskopische und mikrobiologische Daten charakterisiert.

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Metabolic products of microorganisms99. Kirromycin

Summary Kirromycin, a new yellow antibiotic, has been isolated from cultures of strain Tü 365 of Streptomyces collinus. It has been characterized by analytical, spectroscopic, and microbiological data.

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98. Mitt.: Bayer, E., Gugel, K. H., Hägele, K., Hagenmaier, H., Jessipow, S., König, W. A., Zähner, H.: Helv. chim. Acta 55, 224–239 (1972).     

The amino-terminal sequence ofStreptomyces griseus carboxypeptidase

The amino-terminal sequence of carboxypeptidase fromStreptomyces griseus was determined using a new protocol for automatic Edman degradation that reduced background noise. The sequence of the first 48 residues is: Asp-Phe-Pro-Pro-Ala-Asp-Ser-Arg-Tyr-His-Asn-Tyr-Ala-Glu-Met-Asn-Ala-Ala-Ile-Asp-Ala-Arg-Ile-Ala-Ala-Asn-Pro-Ser-Ile-Met-Ser-Lys-Arg-Val-Ile-Gly-Lys-Thr-Tyr-Gln-Gly-(Arg)-Asp-Val-Ile-Ala-Val-Lys, which is homologous to that of other zinc-containing carboxypeptidase from vertebrate and invertebrate sources.     

Differentiation ofStreptomyces strains by gas chromatography

Culture fluids of representative strains ofStreptomyces griseus, S. griseoluteus, S. albus, S. viridochromogenes andS. fradiae were distilled at 100 C, the distillates extracted with ether and the concentrated extracts analyzed by dual-channel gas chromatography. Each extract gave a distinctly different chromatogram. The greatest number of clearly separable peaks and the highest yields of volatile products were formed byS. griseus. The possible use of gas chromatography in taxonomic studies of actinomycetes is discussed.     

Transformation ofStreptomyces avermitilis by plasmid DNA

Summary Polyethylene glycol (PEG) efficiently mediated the transformation ofStreptomyces avermitilis protoplasts by plasmid DNA to yield 10⁷ transformants per g of plasmid DNA. Under conditios in which the maximum transformation frequency was observed, the cotransformation frequency exceeded 10%. The number of transformants increased linearly with the amount of DNA and number ofS. avermitilis protoplasts. Relaxed and supercoiled, but not linear DNA transformed protoplasts efficiently. Dimethyl sulfoxide (DMSO)-mediated transformation of protoplasts was 1000-fold less efficient. PEG and, less efficiently, DMSO also mediated the transformation of whole cells ofS. avermitilis by DNA.     

Activation ofStreptomyces viridochromogenes spores by detergents

Constitutively dormant spores ofStreptomyces viridochromogenes germinate rapidly following treatment with 1.0% of the detergents Tween 80, sodium dodecyl sulfate (SDS), or sodium heptadodecyl sulfate. Six other detergents did not activate the spores. Activation by SDS was studied further. The spores were not activated following treatment with 0.09% or less of SDS for 60 min at 37°C. Activation was complete within 1 to 2 min of treatment with 1.0% SDS. the SDS-activated spores became deactivated during incubation in buffer. Deactivation was slow at 4°C and complete after incubation for 12 h at 25°C or 6 h at 37°C. The endogenous respiratory rate of the spores was increased 3-fold by SDS activation.     

Sporulation ofStreptomyces roseosporus in submerged culture

Summary A soil isolate ofStreptomyces roseosporus was found to produce spores in stirred submerged culture. Both biological mass and respiratory activity increased during the sporulation process. Contrary to other reports, the differentiation process was not purposefully initiated by critical manipulation of either nutritional or environmental conditions.     

Transformation ofStreptomyces lincolnensis protoplasts with plasmid vectors

A method for the preparation and regeneration of protoplasts of Streptomyces lincolnensis is described. Mycelium in the early exponential phase appeared to be most suitable for this purpose and yielded up to 25% regenerated intact cells. Transformation of S. lincolnensis protoplasts was achieved using broad-host-range streptomycete plasmid vectors pIJ622, pMP66, pRS410 and pIJ943 constructed from replicons pIJ101, pSLG33 and SCP2. The efficiency of transformation was 3.10(3) transformants per micrograms plasmid DNA when (2-5).10(7) recipient protoplasts were used. Interspecific transformations showed that there is no efficient restriction system in S. lincolnensis that would limit the transfer of genetic information from S. lividans or E. coli.