title: ATPase and GTPase activities associated with a specific 5S RNA-protein complex.
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.
mesh_terms: D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000378:metabolism*; D005672:Fusidic Acid / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D010455:Peptides / Q000494:pharmacology; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010761:Phosphorus Radioisotopes; D011485:Protein Binding; D012329:RNA, Bacterial / Q000378:metabolism*; D012335:RNA, Ribosomal / Q000378:metabolism*; D013696:Temperature
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D010455:Peptides; D010761:Phosphorus Radioisotopes; D012329:RNA, Bacterial; D012335:RNA, Ribosomal; D005672:Fusidic Acid; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D010744:Phosphoric Monoester Hydrolases; D000251:Adenosine Triphosphatases