Inhibition of Bacterial RNA Polymerase by Streptolydigin: Stabilization of a Straight-Bridge-Helix Active-Center Conformation
نویسندگان
چکیده
We define the target, mechanism, and structural basis of inhibition of bacterial RNA polymerase (RNAP) by the tetramic acid antibiotic streptolydigin (Stl). Stl binds to a site adjacent to but not overlapping the RNAP active center and stabilizes an RNAP-active-center conformational state with a straight-bridge helix. The results provide direct support for the proposals that alternative straight-bridge-helix and bent-bridge-helix RNAP-active-center conformations exist and that cycling between straight-bridge-helix and bent-bridge-helix RNAP-active-center conformations is required for RNAP function. The results set bounds on models for RNAP function and suggest strategies for design of novel antibacterial agents.
منابع مشابه
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ورودعنوان ژورنال:
- Cell
دوره 122 شماره
صفحات -
تاریخ انتشار 2005