摘要:

AbstractThe detection, fermentation, isolation, physicochemical and biological properties of violamycin, a new antibiotic produced by a strain ofStreptomyces violaceusIMET JA 6844 are described. Violamycin is a mixture of the complexes violamycin A and violamycin B. Violamycin A is mainly a complex of aminoglycosides of ϵ‐isorhodomycinone, β‐rhodomycinone, and α2‐rhodomycinone. The sugar component is rhodosamine. Violamycin B is mainly a complex of di‐ and triglycosides of ϵ‐isorhodomycinone, β‐rhodomycinone, and α2‐rhodomycinone. The sugar components of the diglycoside are rhodosamine and deoxy‐L‐fucose, the sugar components of the triglycoside are rhodosamine, deoxy‐L‐fucose, and rhodinose. Violamycin complexes A and B consist of constituents which are similar to other known members of anthracycline antibiotics but can be differentiated from them by physicochemical and biological properties, specially ϵ‐isorhodomycinone which so far has not been determined as a constituent of an antibiotic. The producer of violamycin was detected by means of the “BIP” test method. Violamycin can be isolated from fermentation filtrates and mycelium by extraction with lower aliphatic alcohols and can be purified by gel filtration methods. Violamycin has indicator properties and has been shown to possess a strong antimicrobial activity against grampositive bacteria and mycobacteria, including such strains which produce inactivating enzymes for different commercial antibiotics. Violamycin has growth inhibiting activity to a lower extent also in respect of gramnegative bacteria but has no antibiotic action in respect of yeasts and fungi. In addition to its antimicrobial activity, violamycin shows cytostatic action on mammalian cellsin vitroand experimentally induced tumors of the mouse. Violamycin inhibited bacterial viruses in their multiplication by intracellular action without simultaneous blocking of the metabolism and growth of the host cells. The LD50of violamycin A in mice was 15 mg/kg when administered intraperitoneally and 2 mg/kg on intraperiton

ISSN:0044-2208    

DOI:10.1002/jobm.19740140702

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractIn order to detect specific inhibitors of DNA synthesis with potential cancerostatic properties from microbial or chemical sources, a complex screening programin vitroandin vivohas been developed. This screening program consists both of molecularbiological models and rodent transplanted tumor systems. The microbiological screening program has proved to be of value in the primary selection of 95 mostly new synthesized compounds belonging to the C‐ and N‐MANNICHbases with or without nitrogen mustard groups. All the compounds detected by this screening are potential inhibitors of DNA synthesis and, therefore, able to disturb selectively mechanisms operating both in microbial and mammalian cells,e. g., replication, transcription, recombination, excission, and integration of DNA. Positive results concerning the correlation between effectivityin vitroandin vivoantitumor activity using rodent transplanted tumor systems are presented. Since most of the present day, alkylating agents are selectively toxic for cells which actively synthesize DNA, it is not surprising that there is some degree of correlation between antitumor effect and effects on various microbial or other rapidly growing organisms. However, evidence that agents with prophage inducing capability in lysogenic bacteria and/or with activity in the “BIP” test might play a part in cancer chemotherapy is obvious. The selectivity of the microbiological screening models used shows that they are potential screens despite their inabilities, thus far, to detect all active cancero

ISSN:0044-2208    

DOI:10.1002/jobm.19740140703

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractDer Einfluß vonn‐Alkanen und anderen C‐Quellen auf die Synthese der Enzyme des Citratzyklus inAcinetobacter calcoaceticuswird untersucht.Von den Enzymen des Citratzyklus zeigt nur die Malatdehydrogenase eine Abhängigkeit von der C‐Quelle. Die spezifische Aktivität des Enzyms ist nach Wachstum aufn‐Alkanen oder Acetat etwa 4fach höher als nach Wachstum auf Malat und Succinat. Ein Zusatz von Glucose ‐ aber auch von Antibiotica ‐ zum Nährmedium verhindert den durchn‐Alkane oder Acetat bedingten Aktivitätsanstieg.Um Aussagen über die Kontrollmechanismen des Citrat‐ und Glyoxylatzyklus inAcinetobacter calcoaceticuszu machen, werden die erhaltenen Befunde im Zusammenhang mit den Ergebnissen über die Regulation der Enzyme des Glyoxylatzyklus sowie des

ISSN:0044-2208    

DOI:10.1002/jobm.19740140704

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractConsiderable amounts of GTP, GMP, adenosine, guanine, and adenine accumulated inNeurospora crassawhen a culture grown on low phosphate (0.01%) medium was transferred to a high phosphate (1%) medium. The levels of alkaline phosphatase, nucleotidase, and nucleosidase decreased by 2.4, 5.4, and 3 folds, respectively, in cultures grown on high phosphate medium. Substrate kinetics of these enzymes revealed that: (1) alkaline phosphatase isolated from the organism grown on low phosphate medium demonstrates nonlinear reciprocal plots with two distinct apparentKmvalues for β‐glycerophosphate compared to one apparentKmvalue (associated with 32% decrease in the apparentVmaxvalue) obtained with that grown on high phosphate medium; (2) nucleotidases and nucleosidases isolated from organisms cultivated on low phosphate and high phosphate media showed the same apparentKmvalues, 0.25 mM for nucleotidase and 0.909 mM for nucleosidase. There was, however,>3 times decrease in the catalytic activity of the latter enzymes isolated from organisms grown on high phosphate medium as compared to those grown on low phosphate. Inclusion of inorganic phosphate in standard assay mixtures of the three enzymes resulted in a considerable inhibition in the catalytic activities of all of them. High levels of phosphate in the medium caused marked repression of three out of six of alkaline phosphatase, two out of three of nucleotidase, and one out of two of nucleosidase isozymic forms detected in the low phosphate grown cultu

ISSN:0044-2208    

DOI:10.1002/jobm.19740140705

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractSeven thermophilic fungi have been isolated from stacks of oil palm kernels in parts of the Western State of Nigeria. These includeHumicola lanuginosa(GRIFFONandMAUBLANC)BUNCE,Mucor pusillusLINDT,Talaromyces emersoniiSTOLK,Chaetomium thermophile var coprophileCOONEYandEMERSON,Chaetomium thermophile var. dissitumCOONEYandEMERSON,Thermoascus aurantiacusMIEHEsensuAPINIS, andThermoascus crustaceus(APINISandCHESTERS)STOLK. While the last four are new records for Nigeria, they, together withH. lanuginosaandM. pusillus, are also reported on palm kernels for the first time. All are shown to be strongly thermophilic.

ISSN:0044-2208    

DOI:10.1002/jobm.19740140706

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractThe ability ofChaetomium thermophile var. coprophileCOONEYandEMERSONto utilize carbohydrates as carbon sources for growth has been studied in stationary liquid medium at 45 °C. Among the monosaccharides, the highest growth was obtained on mannose, followed by xylose, glucose, and fructose. There was apparently no growth on galactose, sorbose, arabinose, and rhamnose. The oligosaccharides, cellobiose and maltose supported good growth even though growth on the former was much better. The other oligosaccharides tested (sucrose, lactose, melibiose, and raffinose) were not utilized by the fungus. The polysaccharides dextrin and starch were readily available to the fungus, but growth on dextrin was higher. Out of the two remaining carbon sources tested, there was very good growth on malt extract while mannitol was not utilized. The rate of growth and the accompanying pH changes on glucose, mannose, maltose, dextrin, starch, and malt extract were also studied. There was an initial drop, then a rise, and finally a levelling of the pH as growth progressed on all the six carbon sources. The organism grew well and produced abundant fruiting bodies on cellulose, both in liquid and on solid media. Further evidence of its cellulolytic nature was supplied by its ability to clear cellulose in an agar medium

ISSN:0044-2208    

DOI:10.1002/jobm.19740140707

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

摘要:

AbstractBy combination of indirect immunoferritin technique and freeze‐etching (immuno freeze‐etching) M‐protein ofStreptococcus pyogeneswas demonstrated on the surface of the bacterial cells. The distribution of the ferritin particles shows that the antigen is bound on thread‐like structures. The results correspond to the localization of the M‐protein observed in ultrathin sections from the same

ISSN:0044-2208    

DOI:10.1002/jobm.19740140708

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

ISSN:0044-2208    

DOI:10.1002/jobm.19740140709

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

ISSN:0044-2208    

DOI:10.1002/jobm.19740140710

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY

ISSN:0044-2208    

DOI:10.1002/jobm.19740140713

出版商:Akademie‐Verlag    

年代:1974

数据来源: WILEY