期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1974
卷号：71
期号：9
页码：3470-3473
DOI：10.1073/pnas.71.9.3470
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The stringent factor-catalyzed, ribosome-dependent synthesis of guanosine polyphosphates is found to be reversible. The reverse reaction specifically requires 5'-AMP as the pyrophosphoryl acceptor, and guanosine 5'-triphosphate-3'-diphosphate is preferentially utilized as the pyrophosphoryl donor. The primary products of the reaction are GTP and ATP. The reverse reaction is strongly inhibited by the antibiotics thiostrepton and tetracycline, and by ATP and {beta}-{gamma}-methylene-adenosine-triphosphate, but not by ADP, GTP, and GDP. The reverse reaction occurs under conditions for nonribosomal synthesis. The overall reaction for stringent factor-catalyzed guanosine polyphosphate formation may thus be formulated: (p)pp5'G + ppp5'A {rightleftharpoons} (p)pp5'G3'pp + p5'A.
关键词：guanosine 5′-diphosphate-3′-diphosphate ; guanosine 5′-triphosphate-3′-diphosphate ; relaxed control ; ribosomes
