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：5
页码：1634-1638
DOI：10.1073/pnas.71.5.1634
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Spectinomycin at low concentrations inhibits initiating ribosomes but not ribosomes already engaged in chain elongation. The initiating ribosomes are blocked in some step after formation of the initiation complex, probably the first translocation. Cells inhibited by spectinomycin accumulate polysomes, and these have proved to be unstable polyinitiation complexes: they can be pulse-labeled with methionine but not with valine, and they disappear after addition of rifampicin. Hence, the blocked ribosomes evidently are released and then reinitiate. In heterozygotes this cyclic reinitiation by the sensitive ribosomes, each blocking an initiation site for an average of 10-15 min, can explain (just as with streptomycin) the dominance of sensitivity over resistance.
