Conformational transitions during FtsK translocase activation of individual XerCD-dif recombination complexes.
نویسندگان
چکیده
Three single-molecule techniques have been used simultaneously and in tandem to track the formation in vitro of single XerCD-dif recombination complexes. We observed the arrival of the FtsK translocase at individual preformed synaptic complexes and demonstrated the conformational change that occurs during their activation. We then followed the reaction intermediate transitions as Holliday junctions formed through catalysis by XerD, isomerized, and were converted by XerC to reaction products, which then dissociated. These observations, along with the calculated intermediate lifetimes, inform the reaction mechanism, which plays a key role in chromosome unlinking in most bacteria with circular chromosomes.
منابع مشابه
FtsK translocation on DNA stops at XerCD-dif
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 110 43 شماره
صفحات -
تاریخ انتشار 2013