Horne JR, Erdmann VA. ATPase and GTPase activities associated with a specific 5S RNA-protein complex.
Proc Natl Acad Sci U S A 1973;
70:2870-3. [PMID:
4355369 PMCID:
PMC427128 DOI:
10.1073/pnas.70.10.2870]
[Citation(s) in RCA: 49] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
An RNA-protein complex consisting of 5S RNA and two ribosomal proteins, B-L5 and B-L22, was isolated from Bacillus stearothermophilus ribosomes and found to be active in GTP hydrolysis. This activity was not influenced by elongation factor G. Further analysis of this complex showed that it was also able to hydrolyze ATP. Inhibition studies revealed that ATP was a noncompetitive inhibitor of GTP and that GTP was also a noncompetitive inhibitor of ATP, indicating that two different enzymatic sites were involved. Differences in pH optimum and optimal temperature also point to a twosite enzyme complex. Both enzymatic hydrolyses were inhibited by thiostrepton and fusidic acid, which are known inhibitors of protein synthesis.
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