Engagement of arginine finger to ATP triggers large conformational changes in NtrC1 AAA+ ATPase for remodeling bacterial RNA polymerase.


Journal Article

The NtrC-like AAA+ ATPases control virulence and other important bacterial activities through delivering mechanical work to σ54-RNA polymerase to activate transcription from σ54-dependent genes. We report the first crystal structure for such an ATPase, NtrC1 of Aquifex aeolicus, in which the catalytic arginine engages the γ-phosphate of ATP. Comparing the new structure with those previously known for apo and ADP-bound states supports a rigid-body displacement model that is consistent with large-scale conformational changes observed by low-resolution methods. First, the arginine finger induces rigid-body roll, extending surface loops above the plane of the ATPase ring to bind σ54. Second, ATP hydrolysis permits Pi release and retraction of the arginine with a reversed roll, remodeling σ54-RNAP. This model provides a fresh perspective on how ATPase subunits interact within the ring-ensemble to promote transcription, directing attention to structural changes on the arginine-finger side of an ATP-bound interface.

Full Text

Cited Authors

  • Chen, B; Sysoeva, TA; Chowdhury, S; Guo, L; De Carlo, S; Hanson, JA; Yang, H; Nixon, BT

Published Date

  • November 2010

Published In

Volume / Issue

  • 18 / 11

Start / End Page

  • 1420 - 1430

PubMed ID

  • 21070941

Pubmed Central ID

  • 21070941

Electronic International Standard Serial Number (EISSN)

  • 1878-4186

International Standard Serial Number (ISSN)

  • 0969-2126

Digital Object Identifier (DOI)

  • 10.1016/j.str.2010.08.018


  • eng