Abstract
The betaine-stimulated differential synthesis of vitamin B12, i.e., the increase in B12 per increase in dry cell weight, by Pseudomonas denitrificans was inhibited by rifampin and chloramphenicol but not by benzylpenicillin and carbenicillin at concentrations of antibiotic that inhibit growth. The level of the first enzyme of corrin (and porphyrin) biosynthesis, δ-aminolevulinic acid synthetase, was decreased to a much greater degree by rifampin and chloramphenicol than by the penicillins. These data support the concept that betaine stimulation of B12 synthesis is a result of its stimulation of synthesis of δ-aminolevulinic acid synthetase, a labile and presumably rate-limiting enzyme of corrin formation requiring continuous induction. In further support of this hypothesis, it was found that chloramphenicol immediately interfered with both vitamin B12 and δ-aminolevulinic acid synthetase formation, no matter when it was added to the system.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
- Demain A. L., Daniels H. J., Schnable L., White R. F. Specificity of the stimulatory effect of betaine on the vitamin B12 fermentation. Nature. 1968 Dec 28;220(5174):1324–1325. doi: 10.1038/2201324a0. [DOI] [PubMed] [Google Scholar]
- Demain A. L., White R. F. Porphyrin overproduction by Pseudomonas denitrificans: essentiality of betaine and stimulation by ethionine. J Bacteriol. 1971 Aug;107(2):456–460. doi: 10.1128/jb.107.2.456-460.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lago B. D., Demain A. L. Alternate requirement for vitamin B12 or methionine in mutants of Pseudomonas denitrificans, a vitamin B12-producing bacterium. J Bacteriol. 1969 Jul;99(1):347–349. doi: 10.1128/jb.99.1.347-349.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- White R. F., Demain A. L. Catabolism of betaine and its relationship to cobalamin overproduction. Biochim Biophys Acta. 1971 Apr 20;237(1):112–119. doi: 10.1016/0304-4165(71)90036-5. [DOI] [PubMed] [Google Scholar]