Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 112 (1977), S. 283-285 
    ISSN: 1432-072X
    Keywords: Wine yeasts ; Sulfur metabolism ; Regulation ; Sulfate uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Five different strains of wine yeasts were investigated with respect to active uptake of [35S] sulfate and its regulation by methionine. Considerable differences exist between “low” and “high” sulfite-producing strains in the initial velocity of sulfate uptake. Further differences were established in repression of sulfate permease by l-methionine, most evident in a total lack of repression in one of the “high” sulfite producers. These findings explain in part variable sulfite and sulfide formation.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 121 (1979), S. 251-253 
    ISSN: 1432-072X
    Keywords: Wine yeasts ; Sulfite formation ; Sulfur metabolism ; OAS/OAHS-sulfhydrylase regulation ; Serine sulfhydrase regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four strains of wine yeasts of two different species (Saccharomyces cerevisiae var. ellipsoideus and Saccharomyces bayanus) were investigated with respect to the influence of various sulfur compounds on the formation of O-acetylserine sulfhydrylase, O-acetylhomoserine sulfhydrylase and serine sulfhydrase. The specific enzyme activities were followed over a growth period of 96 h. In the presence of sulfate, sulfite and djencolic acid during exponential growth, a moderate increase of O-acetylserine sulfhydrylase and O-acetylhomoserine sulfhydrylase activities was recognized. In three strains cysteine and methionine prevented this derepression. At the end of the exponential growth phase, biosynthesis of these two enzymes was suppressed again. Serine sulfhydrase showed a modified regulation which indicates that its synthesis and the synthesis of O-acetylserine and O-acetylhomoserine sulfhydrylases are not coordinated.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The anaerobic degradation of p-cresol under denitrifying conditions by a bacterial consortium was studied in batch and continuous cultures. Concentrations up to 3 mm were degraded within 5–6 days with 4-hydroxybenzyl alcohol, 4-hydroxybenzaldehyde and 4-hydroxybenzoate as intermediates. Steady states could be maintained at only one dilution rate, D=0.04 h−1. A further increase in the dilution rate to 0.0 8 h−1 resulted in culture wash-out. An estimation of the Saturation constant was made (〈1 mg/l), taking the maximum specific growth rate as 0.045 h−1, thus yielding a value of 0.125 mg p-cresol/l.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The anaerobic degradation of phenol under denitrifying conditions by a bacterial consortium was studied both in batch and continuous cultures. Anaerobic degradation was dependent on NOf3 p− and concentrations up to 4 mm phenol were degraded within 2–5 days. During continuous growth in a fermenter, steady states could be maintained at eight dilution rates (D) corresponding to residence times between 12.5 and 50 h. Culture wash-out occurred at D=0.084 h−1. The kinetic parameters obtained for anaerobic degradation of phenol under denitrifying conditions by the consortium were: maximam specific growth rate = 0.091 h−1; saturation constant = 4.91 mg phenol/l; true growth yield = 0.57 mg dry wt/mg phenol; maintenance coefficient = 0.013 mg phenol/mg dry wt per hour. The Haldane model inhibition constant was estimated from batch culture data giving a value of 101 mg/l. The requirement of CO2 for the anaerobic degradation of phenol with NOf3 p− indicates that phenol carboxylation to 4-hydroxybenzoate was the first step of phenol degradation by this culture. 4-Hydroxybenzoate, proposed as an intermediate of phenol carboxylation under these conditions, was detected only in continuous cultures at very low growth rates (D=0.02 h−1), but was never detected as a free intermediary metabolite either in batch or in continuous cultures.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 118 (1978), S. 249-251 
    ISSN: 1432-072X
    Keywords: Wine yeasts ; Sulfite formation ; Sulfur metabolism ; Sulfite reductase regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four strains of wine yeasts of two different species (Saccharomyces cerevisiae var. ellipsoideus and S. bayanus) were investigated with respect to regulation of NADPH- and benzyl viologen-dependent sulfite reductases by various sulfur sources. The enzyme activity was followed over a growth period of 96 h. The low sulfite-producing strains showed an increased biosynthesis of NADPH-dependent sulfite reductase during the exponential growth phase in the presence of sulfate, sulfite and djencolic-acid. This increase was not observed in the high sulfite-producing strains. Methionine and cysteine prevented this derepression. At the end of the exponential growth phase, enzyme biosynthesis was repressed again, presumably by sulfur-containing amino acids which were produced during growth. The regulatory influence of the various sulfur sources on benzyl viologen dependent sulfitereductase activity is obviously much weaker.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 107 (1976), S. 289-292 
    ISSN: 1432-072X
    Keywords: Wine yeasts ; Sulfur metabolism ; Sulfite formation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Eight different strains of wine yeasts were investigated phenomenologically with respect to their fermentation characteristics and sulfite production. It was established that the amount of produced sulfite is specific for each strain and proceeds parallel to the fermentation of sugar. A reduced production of biomass observed in the strongly sulfite-forming strains might be a result of an intracellular inhibition by the produced sulfite.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 108 (1976), S. 99-104 
    ISSN: 1432-072X
    Keywords: Wine yeasts ; Sulfur metabolism ; Regulation ; Sulfite reductase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The enzyme catalyzing the reduction of sulfite by reduced benzyl viologen (BVH) was partially purified and characterized from two strains of wine yeasts, a sulfite-producing strain and a non-producing strain. Both enzymes showed corresponding features in pH-optima, optima of buffer and benzyl viologen concentrations. The enzymes did not catalyze the reduction of nitrite by reduced viologen dyes, but the reduction of sulfite was uncompetitively inhibited by nitrite. Compounds of sulfur metabolism such as sulfate, thiosulfate, cysteine, serine and methionine did not influence the activity of either of the enzymes. The main differences between the two enzymes exist in the specific activities in crude extracts, the K m -values for sulfite, substrate inhibition rates, and localization in different fractions during (NH4)2SO4 precipitation. The specific activity in crude extracts of the sulfite-producing strain (0.052 μmoles S2- x min-1 x mg-1) was about three fold higher than that of the non-producing strain (0.0179 μmoles S2- x min-1 x mg-1). On the other hand the sulfite-producing strain had a higher K m -value for sulfite (2×10-3 M) and was more strongly inhibited by the substrate than the non-producing strain (6×10-3 M).
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1574-6968
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract Eleven isolates obtained from a laboratory sewage treatment plant, most of them presumptively assigned to the coryneform genera Curtobacterium and Aureobacterium were studied for the presence of intracellular polyphosphates and polyphosphate dependent enzymes. All isolates stored polyphosphates and showed adenylate kinase activities ranging from 64 to 815 mU mg−1. Polyphosphate:AMP phosphotransferase could only be detected in one isolate. Three isolates showed a polyphosphate kinase activity also in minor amounts from 15 to 17 mU mg−1. A polyphosphate dependent NAD or 3-phosphoglycerate kinase could not be detected. Polyphosphate glucokinase activity was measured in cell-free extracts of nine isolates ranging from 2 to 376 mU mg−1. Three isolates showed in addition to the polyphosphate glucokinase, a glucose-6-phosphate-dependent NAD kinase. For the regeneration of NADP from NAD and polyphosphate, this enzyme system may give the isolates a distinct competitive advantage, especially for anabolic processes. The polyphosphate-dependent enzymes reported here may play an additional role in the complex process of ‘biological’ phosphate removal from wastewater.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1574-6941
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract Several soil and subsoil samples from a soil accumulation and from the aquifer of a site of a former pesticide production factory, which were contaminated with chlorinated benzenes (CB), chlorinated phenols (CP) and hexachlorocyclohexanes (HCH) were investigated chemically for their content of individual pollutants, and microbiologically for the presence and the activity of different microorganisms. The samples of the soil accumulation (until 2 m depth) showed a higher content of chlorinated organic compounds (〉 1000 mg extractable halogenated organic substances (EOX) kg−1 soil; ratio CB:HCH:CP = 88:10:2), than the samples from the aquifer (〈 150 mg EOX kg− soil; ratio CB:HCH:CP = 88:6:6). All isomers of CB and CP, and the five important isomers of HCH could be detected in the samples. In samples of the accumulation, 1,2,3,4,-tetrachlorobenzene and pentachlorobenzene were the dominant CB in the upper layers, and 1,2,4-trichlorobenzene in the lower layers. In almost all samples α-HCH was predominant (〉 50%) among the HCH. The major pollutant of samples from the aquifer was 1,2,4-tricholorobenzene (〉 50% of CB). Among the HCH, δ-HCH was predominant, with only three exceptions. Degradation experiments with mixed bacterial cultures showed the aerobic degradation of monochlorobenzene, 1,3- and 1,4-dichlorobenzene, 1,2,4-trichlorobenzene, 1,2,3,4- and 1,2,4,5-tetrachlorobenzene 1,2,3-tricholorobenzene only in combination with 1,2,4-trichlorobenzene, and α-HCH, whereas 1,2-dichlorobenzene, 1,3,5-trichlorobenzene, β-HCH, 4-chlorophenol, and 2,4,5-trichlorophenol were not significantly transformed. It should be stressed that the compounds which were biodegraded in the laboratory were present in relatively high concentrations in situ, indicating limiting factors in their in situ degradation. Soil and subsoil microorganisms were present in numbers up to 105 colony forming units (CFU) g−1 soil. In soil samples, Gram-positive bacteria (coryneforms and Bacillus spp.) were dominant, mainly in the upper layers, but in the subsoil samples of the aquifer the majority of isolates were Gram-negative and could be identified as Pseudomonas stutzeri, Ps. fluorescens, Aeromonas sp. and Acinetobacter sp. The degradation potential observed under laboratory conditions should be studied further under in situ conditions to assess the success of a bioremediation.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1573-0972
    Keywords: Alcaligenes ; chlorophenol ; methylphenol ; meta cleavage pathway ; ortho cleavage pathway
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Alcaligenes xylosoxidans subspecies denitrificans JH1 was enriched with 2-chlorophenol from a mixed culture degrading different chloro- and methylphenols. The strain used all monochloro- and monomethylphenols apart from 2-methylphenol as sole source of energy and carbon with stoichiometric release of chloride. 4-Chlorophenol was mineralized up to a concentration of 1.3 mM. Degradation of mixtures of monochloro- and monomethylphenols occurred at least partially except for the mixture of 2-chlorophenol and 3-methylphenol. Depending upon the growth substrates used, enzymes of the ortho and/or meta cleavage pathway catalysed the degradation of the phenols. The transformation of chlorophenols was concluded to occur exclusively via the ortho cleavage pathway because no chlorocatechol 2,3-dioxygenase activity was found in chlorophenol-grown cells. Degradation of 4-methylphenol in strain JH1 occurred both by the ortho and meta cleavage pathway as indicated by the finding that the ortho- and meta-cleaving dioxygenases were expressed in 4-methylphenol-grown cells. Transformation of methylphenols by the ortho cleavage pathway led to the accumulation of methyllactones as dead-end products. Mixtures of methyl- and chlorophenols were metabolized mainly by the ortho cleavage pathway because chlorocatechols formed inactivated the constitutive catechol 2,3-dioxygenase which caused channelling of methylphenols into the ortho cleavage pathway.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...