摘要:

AbstractStable mutants resitant to benzyl alcohol (= Balr) were selected from natural colony populations of several strains ofS. nourseiJA 3890 b. Irrespective of the absence of aerial mycelium formation the majority of the Balrmutants produced the same amount of nourseothricin as their parental strains. The Balrderivative 2/8 showed a higher production of biomass and lipids than its ancestor BF32 under standard conditions of growth. In the presence of increasing concentrations of benzyl alcohol in the medium (0–0.2%), growth of this Balrstrain was more resistant to the toxic agent, and the lipid content dropped more slowly concomitant with aberrant alterations of the composition of fatty acids. The results suggest that Balrstrains represent regulatory mutants whose occurrence in natural populations has been caused either by changes at the level of pleiotropic gene functions or by several, independent genetic alteration

ISSN:0233-111X    

DOI:10.1002/jobm.3620260302

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractBy means of special selective conditions we analyzed the temporal relationship of diploidization and haploidization in the yeastYarrowia lipolytica. These processes could be divided into several steps. Twelve hours after mixing parental strains dissociation products of unstable heterokaryons are selectable. Four hours later karyogamy takes place as shown by isolation of mitotic recombinants. At this time spontaneous haploidization starts which leads to an enrichment of haploid and aneuploid segregants in the cell population. A high portion of chimeric clones which represents the dynamics of segregation were selected at time intervals 16, 23 and 29 hours.We concluded that an unstable heterokaryon should be a connecting link between sexual and parasexual processes inY. lipolytica.

ISSN:0233-111X    

DOI:10.1002/jobm.3620260303

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractThe degradation of l‐ and d‐aromatic amino acids has been studied inCandida maltosa. The following main metabolites were indentified: indolelactate was the degradation product of tryptophan, phenylpyruvate and phenyllactate were that of phenylalanine andp‐hydroxyphenylpyruvate andp‐hydroxyphenyllactate resulted from degradation of tyrosine. The first step of utilization of l‐aromatic amino acids was found to be a transamination. The cells contained increased aromatic aminotransferase activity if grown on medium supplemented with one of the three l‐aromatic amino acids. Three aromatic aminotransferases were separated by DEAE‐cellulose chromatography. The pathway for degradation of d‐aromatic amino acids involves deamination as the initial step. The enzyme was characterized to be a general d‐amino acid oxidase capable of utilizing various d‐amino acids. Synthesis of this enzyme was constitutive. Common products of both enzymatic reactions with the aromatic amino acids were the corresponding aromatic pyruvates. Formation of the aromatic lactate derivatives was catalyzed by an aromatic lactate dehydrogenase. This enzyme possessed a high substrate specificity forp‐hydroxyphenylpyruvate, phenylpyruvate, and indolepyruvate and was synth

ISSN:0233-111X    

DOI:10.1002/jobm.3620260304

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractThirty‐nine isolates and additional reference strains of methanotrophic bacteria were studied with respect to mol % G + C of their DNA and the type of intracytoplasmatic membranes. The results on the whole confirm the former classification scheme of Whittenburyet al. (1970). However, problematic groups such as “Methylocystis” and “Methylobacter” are in need of additional taxonomi

ISSN:0233-111X    

DOI:10.1002/jobm.3620260305

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractMn2+uptake by wild type ofAnacystis nidulansIU 625 follows Michaelis‐Menten type kinetics with apparent saturation at 27 μmol/l of Mn2+. Lineweaver‐Burk plot of the data reveals aKm of 25 μmol/l andVmaxof 1.2 nmol/mg protein · min. The uptake values at different pH (pH 4.0 to 9.0) exhibit a characteristic profile with an optimum at pH 6.0. The Mn2+uptake rate in the dark is found to be similar to that in the light suggesting that energy for transport may not be directly derived from light reactions. The system seems to be specific for Mn2+transport since simultaneous addition of Mg2+partially inhibited the uptake in a competitive manner. Further, the alterations inKmandVmaxvalues of mutants with respect to that of wild type strains suggest a genetic control of the transport

ISSN:0233-111X    

DOI:10.1002/jobm.3620260306

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractButylmaduramycin, a new derivative of maduramycin was isolated from the culture medium of a mutant strain ofActinomadura rubra. This communication describes some biological and physicochemical characteristics of the new antibiotic.

ISSN:0233-111X    

DOI:10.1002/jobm.3620260307

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractAn economic assay to determine the yield of interferon is necessary for the induction, production and purification of interferon.Using the inhibition of cytopathic effect of vesicular stomatitis virus in a microtitre system, we compared the susceptibility of different cell lines against an internal IFNα standard obtained from Sendai virus‐induced human leukocytes. Human fibroblasts carrying trisomy G 21 and bovine MDBK cells showed the highest sensitivity followed by normal human fibroblasts. Human RH kidney cells exhibited a susceptibility similar to that of human WISH amnion cells frequently used by others. The human amnion cell line FL and monkey Vero kidney cells, as described here, were unsuitable for the determination of IFN yiel

ISSN:0233-111X    

DOI:10.1002/jobm.3620260308

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620260310

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractAfter growth on acetate three groups ofAcinetobacterstrains could be indentified with respect to the excretion of a bioemulsifier. Mutants ofA. calcoaceticus69‐V were selected which produced reduced amounts of emulsifie

ISSN:0233-111X    

DOI:10.1002/jobm.3620260311

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY

摘要:

AbstractFlagellar (H) antigens of 189 acrystalliferous spore‐forming bacteria, referable toBacillus cereus, isolated from soils and silkworm litters of Japan, were analyzed by using H antisera againstBacillus thuringiensisH serotypes 1–20. These isolates proved to share common H antigens at a very high frequency of 29.6% (56/189) with the known 16 H serotypes ofB. thuringiensis. This indicates that, in natural environments,B. cereuspossessingB. thuringiensisH antigens is distributed more widely than crystalliferousB. thuringien

ISSN:0233-111X    

DOI:10.1002/jobm.3620260312

出版商:Wiley‐VCH    

年代:1986

数据来源: WILEY