Abstract
Mutations were found which enable Escherichia coli K-12 to form homocysteine in the absence of cystathionase. The formation of homocysteine in the mutant strains required cystathionine gamma-synthetase, the metB gene product, but bypassed the normal intermediate cystathionine. It is concluded that cystathionine gamma-synthetase catalyzes the formation of homocysteine directly from O-succinylhomoserine and an as-yet-unidentified sulfur donor. The mutation apparently causes the formation of this sulfur donor and has been named metQ. The expression of the metQ gene is under catabolite repression.
Full text
PDF
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- CAVALLINI D., MONDOVI B., DE MARCO C., SCIOSCIASANTORO A. Inhibitory effect of mercaptoethanol and hypotaurine on the desulfhydration of cysteine by cystathionase. Arch Biochem Biophys. 1962 Feb;96:456–457. doi: 10.1016/0003-9861(62)90436-8. [DOI] [PubMed] [Google Scholar]
- Clarke L., Carbon J. A colony bank containing synthetic Col El hybrid plasmids representative of the entire E. coli genome. Cell. 1976 Sep;9(1):91–99. doi: 10.1016/0092-8674(76)90055-6. [DOI] [PubMed] [Google Scholar]
- DELAVIER-KLUTCHKO C., FLAVIN M. ROLE OF A BACTERIAL CYSTATHIONINE-BETA-CLEAVAGE ENZYME IN DISULFIDE DECOMPOSITION. Biochim Biophys Acta. 1965 May 18;99:375–377. doi: 10.1016/s0926-6593(65)80137-0. [DOI] [PubMed] [Google Scholar]
- ELLMAN G. L. Tissue sulfhydryl groups. Arch Biochem Biophys. 1959 May;82(1):70–77. doi: 10.1016/0003-9861(59)90090-6. [DOI] [PubMed] [Google Scholar]
- FLAVIN M. Microbial transsulfuration: the mechanism of an enzymatic disulfide elimination reaction. J Biol Chem. 1962 Mar;237:768–777. [PubMed] [Google Scholar]
- Flavin M., Slaughter C. Enzymatic synthesis of homocysteine or methionine directly from O-succinyl-homoserine. Biochim Biophys Acta. 1967 Mar 15;132(2):400–405. doi: 10.1016/0005-2744(67)90158-1. [DOI] [PubMed] [Google Scholar]
- Hong J. S. An ecf mutation in Escherichia coli pleiotropically affecting energy coupling in active transport but not generation or maintenance of membrane potential. J Biol Chem. 1977 Dec 10;252(23):8582–8588. [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Lieberman M. A., Hong J. S. A mutant of Escherichia coli defective in the coupling of metabolic energy to active transport. Proc Natl Acad Sci U S A. 1974 Nov;71(11):4395–4399. doi: 10.1073/pnas.71.11.4395. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lieberman M. A., Simon M., Hong J. S. Characterization of Escherichia coli mutant incapable of maintaining a transmembrane potential. MetC ecfts mutations. J Biol Chem. 1977 Jun 25;252(12):4056–4067. [PubMed] [Google Scholar]
- Savin M. A., Flavin M., Slaughter C. Regulation of homocysteine biosynthesis in Salmonella typhimurium. J Bacteriol. 1972 Aug;111(2):547–556. doi: 10.1128/jb.111.2.547-556.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shimada K., Weisberg R. A., Gottesman M. E. Prophage lambda at unusual chromosomal locations. I. Location of the secondary attachment sites and the properties of the lysogens. J Mol Biol. 1972 Feb 14;63(3):483–503. doi: 10.1016/0022-2836(72)90443-3. [DOI] [PubMed] [Google Scholar]
- VOGEL H. J., BONNER D. M. Acetylornithinase of Escherichia coli: partial purification and some properties. J Biol Chem. 1956 Jan;218(1):97–106. [PubMed] [Google Scholar]