Affiliation:
1. Department of Biology, Emory University, Atlanta, Georgia 30322.
Abstract
Two forms of ATP:GTP 3'-pyrophosphotransferase (guanosine pentaphosphate synthetase) have been purified from Streptomyces antibioticus. The larger form has an M(r) of 88,000, while the M(r) of a smaller form is 47,000. Both synthetase forms are active in the formation of guanosine 5'-triphosphate, 3'-diphosphate in reaction mixtures containing methanol. Unlike the RelA protein from Escherichia coli, the synthetases from S. antibioticus do not use GDP efficiently as a substrate. Experiments using crude extracts of S. antibioticus mycelium and the 88,000-M(r) form of guanosine pentaphosphate synthetase strongly suggest that the 47,000-M(r) species is produced by proteolysis of the larger species. This conclusion is supported by the observation that antibody to either protein reacts with the other protein. Thus, the 88,000-M(r) species may be the catalytically relevant protein in vivo. Unlike the RelA protein, the 88,000-M(r) protein is not activated by ribosomes. Modest levels of guanosine pentaphosphate synthesis were observed in mycelial extracts derived from nine other actinomycetes.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology
Reference35 articles.
1. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding;Bradford M. M.;Anal. Biochem.,1976
2. The control of ribonucleic acid synthesis in Escherichia coli. IV. Relevance of unusual phosphorylated compounds from amino acid starved stringent strains;Cashel M.;J. Biol. Chem.,1969
3. An improved method for thin-layer chromatography of nucleotide mixtures containing 32P-labeled orthophosphate;Cashel M.;J. Chromatogr.,1970
4. Cashel M. and K. E. Rudd. 1987. The stringent response p. 1410-1438. In F. C. Neidhardt J. L. Ingraham K. B. Low B. Magasanik M. Schaechter and H. E. Umbarger (ed.) Escherichia coli and Salmonella typhimurium: cellular and molecular biology vol. 2. American Society for Microbiology Washington D.C.
5. Phenoxazinone synthase from Streptomyces antibioticus: purification of the large and small enzyme forms;Choy H. A.;Arch. Biochem. Biophys.,1981
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