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J. T. Keltjens J. M. H. Hermans G. J. F. A. Rijsdijk C. Van der Drift G. D. Vogels 《Antonie van Leeuwenhoek》1988,54(3):207-220
F430 is the prosthetic group of the methylcoenzyme M reductase of methanogenic bacteria. The compound isolated from Methanosarcina barkeri appears to be identical to the one obtained from the only distinctly related Methanobacterium thermoautotrophicum. F430 is thermolabile and in the presence of acetonitrile or C10
in4
sup-
two epimerization products are obtained upon heating; in the absence of these compounds F430 is oxidized to 12, 13-didehydro-F430. The latter is stereoselectively reduced under H2 atmosphere to F430 by cell-free extracts of M. barkeri or M. thermoautotrophicum. H2 may be replaced by the reduced methanogenic electron carrier coenzyme F420.Abbreviations CH3S-CoM
methylcoenzyme M, 2-methylthioethanesulfonic acid
- HS-CoM
coenzyme M, 2-mercaptoethanesulfonic acid
- F430
Ni(II) tetrahydro-(12, 13)-corphin with a uroporphinoid (III) ligand skeleton
- 13-epi-F430 and 12,13-di-epi-F430
the 12, 13- and 12, 13-derivatives of F430
- 12, 13-didehydro-F430
F430 oxidized at C-12 and C-13
- coenzyme F420
7,8-didemethyl-8-hydroxy-5-deazaflavin derivative
- coenzyme F420H2
reduced coenzyme F420
- MV+
methylviologen semiquinone
- HPLC
high-performance liquid chromatography 相似文献
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Competence pheromone, oligopeptide permease, and induction of competence in Streptococcus pneumoniae 总被引:5,自引:4,他引:1
Geneviève Alioing Chantal Granadel Donald A. Morrison Jean-Pierre Claverys 《Molecular microbiology》1996,21(3):471-478
An unmodified heptadecapeptide pheromone capable of eliciting competence for genetic transformation in Streptococcus pneumoniae has recently been identified and characterized. In considering possible signaltransduction mechanisms for the peptide, the previously characterized Ami oligopeptide permease and the three highly homologous oligopeptide-binding lipoproteins, AmiA. AliA, and AliB, appeared to be good candidates for receptors. We therefore compared the spontaneous transformability of Ami, AliA and AliB mutants to that of an isogenic wild-type strain and we investigated the response of the various mutants to treatment with synthetic competence-stimulating peptide (CSP). Our results clearly demonstrate that neither Ami nor any of the three highly homologous oligopeptide-binding lipoproteins identified so far in S. pneumoniae are required for competence induction following treatment with synthetic CSP. Although the existence of a fourth unidentified oligopeptide-binding lipoprotein and/or a second oligopeptide permease operon could not be completely ruled out, we favour the hypothesis that CSP signal transmission rather involves a two-component regulatory system. Although none of the single or double Ami and Ali mutants tested appeared severely affected for competence, an exceptional aliB plasmid-insertion mutation abolished competence completely. In addition, the triple AmiA-AliA-AliB mutant differed from wild type in showing no sharp peak of competence but exhibiting transformability throughout the exponential phase of growth. These and previous observations are discussed and a general hypothesis is proposed to account for the modulation of competence by peptide permease mutants in S. pneumoniae. 相似文献
6.
G. D. Vogels C. van der Drift C. K. Stumm J. T. M. Keltjens K. B. Zwart 《Antonie van Leeuwenhoek》1984,50(5-6):557-567
Methanogenesis involves a novel set of coenzymes as one-carbon and electron carriers. Consequently, metabolic processes of
methanogens deviate from those present in non-methanogenic bacteria. Methanogenic bacteria can be classified on the basis
of substrate utilization. Group I (24 species) grows at the expense of hydrogen plus CO2 and/or formate and group II (7 species) uses methanol and/or acetate. Hydrogen-consuming methanogens are found as epi- or
endosymbionts of anaerobic ciliates. 相似文献
7.
Jan T. Keltjens Henny J. Rozie Godfried D. Vogels 《Archives of biochemistry and biophysics》1984,229(2):532-537
During purification procedures and upon aerobic heating with alkali a green-yellow degradation fluorescent product (GY) was formed from 5,10-methenyl-5,6,7,8-tetrahydromethanopterin, an intermediate in the reduction of CO2 to methane [J. T. Keltjens, L. Daniels, H. G. Janssen, and G. D. Vogels (1983)Eur. J. Biochem.130, 545–552]. GY was suggested to be a 6-(1-oxo)-7,8-dihydropterin. On the basis of the spectral properties and the results of degradation studies, it was now shown that the structure of GY is 6-acetyl-7-methyl-7,8-dihydropterin. This structure was confirmed by synthesis of the compound and other reference substances. 相似文献
8.
Evolution of Volatile Sulfur Compounds during Laboratory-Scale Incubations and Indoor Preparation of Compost Used as a Substrate in Mushroom Cultivation 总被引:2,自引:1,他引:1 下载免费PDF全文
P. J. L. Derikx F. H. M. Simons H. J. M. Op den Camp C. van der Drift L. J. L. D. Van Griensven G. D. Vogels 《Applied microbiology》1991,57(2):563-567
Volatile sulfur compounds are known to be produced during the preparation of compost used as a substrate in mushroom cultivation. Because they cause odor problems, attempts have been made to reduce the production of these compounds. The influences of temperature and various additions on the production of volatile sulfur compounds from composting material were tested on laboratory-scale preparations. The production of H2S, COS, CH3SH, and (CH3)2S was proven to be a biological process with an optimal temperature that coincides with the optimal temperature for biological activity. The formation of CS2 and (CH3)2S2 was shown to be a nonbiological process. The emission of volatile sulfur compounds during the indoor preparation of mushroom compost appeared to be remarkably reduced (about 90%) as compared with the emission during the conventional outdoor process. Introduction of this indoor composting process would result in a significant reduction in environmental pollution. 相似文献
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