摘要:

AbstractIf in stationary growth phases appearing in the submerged cultivation ofStreptomyces griseusseveral times the consumption rates of glucose and oxygen and the rates of streptomycin formation are put in relation, the following results are obtained: The yield coefficientY spof glucose was below 0.1. Since from the stoichiometric equation of turnover for the biosynthesis of the streptomycin follows that the substrate and the product are in the same weight relation, it was possible to check whether the quantity of glucose that does not appear in the streptomycin is used for the energy supplying synthesis or concervation reactions. As a characteristic value was built up the quotientqo3/qglucthat in total substrate oxidations takes the numerical value 6. This quotient varied between 2.0 and 6.0 so that anabolic side reactions during the production of secondary substances were concluded from. As possibilities are discussed syntheses of analytically disregarded primary metabolites or preliminary steps of the biosynthesis of streptomycin. Due to the decrease of the enthalpy production by anabolic reaction steps in stationary growth phases follows a physiological‐energetical importance of microbial product syntheses with likely evolutive act

ISSN:0044-2208    

DOI:10.1002/jobm.19800200602

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

摘要:

AbstractA fibrinolytic enzyme obtained fromB. subtiliswas purified, using DEAE‐cellulose column chromatography, and gel filtration on Sephadex G‐100. The preparation was homogeneous as tested by gel filtration on Sephadex G‐200, and disc electrophoresis.The molecular weight of this enzyme was 29.400 estimated by gel filtration on Sephadex G‐100. The optimum pH for enzyme activity was 7.2. Copper ions significantly increased enzyme activity, while Zn++and Mn++caused marked inh

ISSN:0044-2208    

DOI:10.1002/jobm.19800200603

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

摘要:

AbstractTwo fibrinolytic enzymes isolated fromB. subtilisand fromB. polymyxawere purified using a five step method. The pH optimum for the enzyme fromB. subtiliswas 7.2 and for the enzyme fromB. polymyxawas 7.0. Both enzymes were activated by Cu++.The molecular weight of the first enzyme was 29,400 and that for the second enzyme was 18,000 on the basis of gel filtration on Sephadex G‐100.The enzyme fromB. subtilishas higher affinity to buffalo fibrin than towards human fibrin. The enzyme fromB. polymyxahas higher affinity to human fibrin than towards buffalo fibri

ISSN:0044-2208    

DOI:10.1002/jobm.19800200604

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

摘要:

AbstractIn order to investigate the control behaviour of dihydroxyacetone kinase of methanol‐grownCandida methylicaunder nearly physiological conditions kinetic and regulatory studies were carried outin situ. Yeast cells were made permeable to substrate and reaction products by treatment with Triton X‐100. Normal Michaelis‐Menten kinetics resulted in dependence upon the dihydroxyacetone concentration, both at the pH optimum of 7.6 and near the physiological pH‐value of 6.5. TheKmobtained for dihydroxyacetone was 0.02 mm, independent of the pH‐value. The plots of dihydroxyacetone kinase activity as a function of the ATP concentration revealed complex kinetic characteristics with plateau regions. The maximum reaction rate was reached only after a lag time both at pH 7.6 and concentrations of ATP higher than 5 mm and at pH 6.5 and concentrations of ATP higher than 1.25 mm. Among a great number of tested metabolites no inhibitors of dihydroxyacetone kinase were found. Dihydroxyacetone kinase activity depending upon energy charge according to Atkinson exhibited curves of the U‐type. These results and further data concerning the regulation of other enzymes obtained withC. methylicaand other yeasts were the basis to propose a preliminary overall model of fine control of the carbon and energy metabolism of methanol‐uti

ISSN:0044-2208    

DOI:10.1002/jobm.19800200605

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

摘要:

AbstractCell‐free extracts of the obligate methanol‐utilizing bacteriumPseudomonasW6 catalyze the oxydation of isocitrate to α‐ketoglutarate in the presence of NAD+and NADP+. After electro‐focusing of the crude extract ofPseudomonasW6 actually two distinct bands each of NAD+‐linked isocitrate dehydrogenase (NAD+‐IDH) and of NADP+‐linked isocitrate dehydrogenase (NADP+‐IDH) could be observed. The NAD+‐IDH was completely separated from the NADP+‐IDH by employing DEAE ion exchange chromatography and further purified by affinity chromatography using Cibacron blue F 3G‐A.The NAD+‐IDH was inhibited by a high energy charge, whereas the NADP+‐IDH was found to be independent of energy charge. Consequently the NAD+‐IDH showed the control behaviour of an enzyme of an energy‐generating sequence which, however, equally fulfils a catabolic and an anabolic function. With respect to the inhibition by reduced pyridine nucleotides and α‐ketoglutarate differences between NAD+‐IDH and NADP+‐IDH were also found. Only the NADP+‐linked enzyme exhibited a feedback inhibition by its reaction products α‐ketoglutarate and NADPH. This control behaviour gives evidence for the biosynthetic function of the NADP+‐IDH. These results confer an amphibolic character to the sequence from citrate to α‐ketoglutarate in t

ISSN:0044-2208    

DOI:10.1002/jobm.19800200606

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

摘要:

AbstractAnaerobic growth on an amino acids mixture in the presence of nitrate of a strain ofK. pneumoniaeisolated from soil depended on the presence of serine in the mixture. This organism grew on serine as sole carbon source under anaerobic conditions in the presence of nitrate but not in its absence. Glycylglycine could replace serine. Serine was degraded to acetate, formate, pyruvate, acetone and acetoin with formation of nitrite under these conditions. These products were practically not different from those formed from glucose. Resting cells decomposed serine also in the absence of nitrate forming butanediol and a large amount of formate in place of decreased amounts of acetate and pyruvate. These cells also anaerobically decomposed alanine to products similar to those from serine and phenylalanine to phenylacetate and formate only in the presence of nitrate. Valine was not catabolized under the same conditions. Serine was decomposed to pyruvate and ammonia in the crude extract in the presence and absence of nitrate, indicating participation of serine dehydratase in its breakdown. Phenylalanine appears to be decomposed to phenylpyruvate by transamination coupled to glutamate oxidation and then to phenylacetate and formate. Little growth on serine under anaerobic conditions in the absence of nitrate may be accounted for by the small gain of ATP in the anaerobic breakdown of serine by this organism.

ISSN:0044-2208    

DOI:10.1002/jobm.19800200607

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

摘要:

AbstractEs konnte erstmals gefunden werden, daß die Hefezellwand eine strahlenschützende Funktion besitzt. Dieser Nachweis gelang durch vergleichende Untersuchungen an Hefen, deren Wand partiell oder völlig entfernt worden war bzw. wo die Bindungen zwischen den die Wand aufbauenden Makromolekülen (Disulfidbrücken, Ca++‐Brücken) zerstört wurden. Das Mannan der Zellwand ist für die Strahlenresistenz verantwortlich. Diese Schutzfunktion wird verstärkt, wenn Mannan und Glutathion, ein zelleigener Protektor der Hefe, zusa

ISSN:0044-2208    

DOI:10.1002/jobm.19800200608

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

ISSN:0044-2208    

DOI:10.1002/jobm.19800200611

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

ISSN:0044-2208    

DOI:10.1002/jobm.19800200613

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY

ISSN:0044-2208    

DOI:10.1002/jobm.19800200616

出版商:Akademie‐Verlag    

年代:1980

数据来源: WILEY