Hypernegative Supercoiling Inhibits Growth by Causing RNA Degradation
نویسندگان
چکیده
منابع مشابه
Hypernegative supercoiling inhibits growth by causing RNA degradation.
Transcription-induced hypernegative supercoiling is a hallmark of Escherichia coli topoisomerase I (topA) mutants. However, its physiological significance has remained unclear. Temperature downshift of a mutant yielded transient growth arrest and a parallel increase in hypernegative supercoiling that was more severe with lower temperature. Both properties were alleviated by overexpression of RN...
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DNA supercoiling and topoisomerases have long been known to affect transcription initiation. In many studies, topA mutants were used to perturb chromosomal supercoiling. Although such studies clearly revealed that supercoiling could significantly affect gene expression, they did not tell much about the essential function(s) of DNA topoisomerase I, encoded by topA. Indeed, the topA mutants used ...
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ژورنال
عنوان ژورنال: Journal of Bacteriology
سال: 2008
ISSN: 0021-9193,1098-5530
DOI: 10.1128/jb.00680-08