摘要:

AbstractFractionation of cell‐free extracts ofLactobacillus caseiNCDO 151 (grown in MAN'set al.(1960) broth) by polyacrylamide disc electrophoresis showed the presence of 4 constitutive peptidases. The enzymes appear to be a tripeptidase with a narrow substrate specificity, two true dipeptidases with identical broad‐specificity, and a probable carboxypeptidase with broad‐specificity. A probable amino peptidase could also be isolated from the cell‐free extract by density gadient electrofocusing. Growth of the organism in skim milk resulted in the formation of two inducible dipeptidases.Examination of 5 other strains ofL. caseifor the presence of the two constitutive dipeptidases and the carboxypeptidase confirmed the results obtained for the species. Some strains, however, had one more peptidase. The peptidases of the strains differed relatively in the activity and substrate specificity from strain to strain. On polyacrylamide gel, the peptidase activity ofL. plantarumappeared as one band only, probably of a carboxype

ISSN:0233-111X    

DOI:10.1002/jobm.3620270302

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe metabolization of L‐carnitine was studied using whole cells ofEscherichia coli044 K74. It showed features of an epigenetical control. L‐carnitine and crotonobetaine were able to induce the carnitine‐reducing system. Oxygen and nitrate as electron acceptors, γ‐butyrobetaine as final product of carnitine transformation inE. colias well as glucose repress the carnitine metabolization. Other betaines and structurally related compounds did not show any effect neither as inductors nor as re

ISSN:0233-111X    

DOI:10.1002/jobm.3620270303

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620270304

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractNourseothricin (streptothricin) causes disturbances (perforations) in the outer membrane of sensitiveE. colistrains allowing lysozyme and deoxycholate, but not the periplasmic alkaline phosphatase to penetrate. EDTA slightly increases, but Mg++ions slightly decrease this effect. The cell walls of three from four nourseothricin‐resistant strains do not become permeable under these conditions, but remain sensitive against TRIS/EDTA. Nourseothricin is supposed to pass the outer membrane of sensitive bacteria via some kind of “self‐promoting” pathway. This way can (but need not) be blocked in resistant

ISSN:0233-111X    

DOI:10.1002/jobm.3620270305

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractExtracellular components of plant pathogenic bacteria were obtained from their culture medium as well as from the whole cells by using NaCl 1 M, pH 6.0; 20% sucrose dissolved in 0.03 M Tris buffer, pH 8.0; or 0.05 M Na2EDTA.All the extracts fromErwinia carotovorasubsp.carotovora, Xanthomonas campestrispv.campestris, Pseudomonas syrinagaepv.phaseolicola, Xanthomonas campestrispv.phaseoli, Pseudomonas solanacearum, andErwinia carotovorasubsp.atroseptica, were assayed for hemagglutinating activity on sheep, rabbit and chicken red blood cells (RBCs).The only active extracts were those obtained by NaCl treatment. They agglutinated sheep and rabbit erythrocytes. Extracts fromE. carotovorasubsp.atrose pticagave rise to the high agglutination titer on rabbit RBCs. These extracts had the lowest polysaccharide/protein ratio.E. carotovorasubsp.carotovoraextracts showed only a low titer (18.5 units).The agglutinating activity present in NaCl extracts of the bacteria tested was inhibited by different carbohydrates to various extent. Extracts fromE. carotovorasubsp.atrosepticaappeared to be the most sensitive ones while those ofE. carotovorasubsp.carotovoraleast sensitive to the presence of sugar.It is suggested that hemagglutinins observed in plant pathogenic bacteria and those in plant host are similar and that both may, in some way, be involved in the plant‐parasite relationshi

ISSN:0233-111X    

DOI:10.1002/jobm.3620270306

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620270308

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractFrom a collection of 28 virulent phages peviously used for the typing ofRhizobiumstrains, four were selected for detailed characterization: 3C forR. trifolii, 3H forR. leguminosarum, 1A and 2A forR. meliloti, respctively. On the basis of their morphology phages 3H and 1A were included into group B and phage 3C into group C according to the classification of BRADLEY (1967). Rceptors for phage 3H were thermosensitive in contrast to those for phages 3C and 2A. Phage 3H kept in phosphate buffer (0.01 M), Na‐citrate or EDTA, lost its activity. Ca++and Mg++protected the infectivity of phages 3H and 3C maintained in phosphate buffe

ISSN:0233-111X    

DOI:10.1002/jobm.3620270309

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620270311

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe composition of fatty acids and the spectrum of macrolide antibiotics produced in 7 mutant strains ofStreptomyces fradiae, a tylosin producer, were investigated. The strains under investigation differed in the production level and representation of individual tylosin‐like compounds. The composition of fatty acids in the mycelium did not depend on the total production. However, the strains producing relomycin in addition to tylosin produced a significantly higher fraction of fatty acids with a higher melting point, and, on the contrary, the strains producing only tylosin or tylosin and desmycosin synthesized a significantly lower proportion of these acids. The results obtained indicate that in addition to the activity and substrate specifity of secondary metabolism enzymes, the composition of the tylosin‐like compounds produced can be influenced by the cell membrane and its funct

ISSN:0233-111X    

DOI:10.1002/jobm.3620270312

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620270313

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY