2024-03-29T10:54:24Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/815792021-11-22T12:47:31Zcom_10261_42com_10261_1com_10261_3284col_10261_295col_10261_3285
2013-09-06T10:01:03Z
urn:hdl:10261/81579
Regulation of the type IV secretion ATPase TrwD by magnesium: Implications for catalytic mechanism of the secretion ATPase superfamily
Ripoll-Rozada, Jorge
Peña, Alejandro
Rivas, Susana
Moro, Fernando
Cruz, Fernando de la
Cabezón, Elena
Arechaga, Ignacio
TrwD, the VirB11 homologue in conjugative plasmid R388, is a member of the large secretion ATPase superfamily, which includes ATPases from bacterial type II and type IV secretion systems, type IV pilus, and archaeal flagellae assembly. Based on structural studies of the VirB11 homologues in Helicobacter pylori and Brucella suis and the archaeal type II secretion ATPase GspE, a unified mechanism for the secretion ATPase superfamily has been proposed. Here, we have found that the ATP turnover of TrwD is down-regulated by physiological concentrations of magnesium. This regulation is exerted by increasing the affinity for ADP, hence delaying product release. Circular dichroism and limited proteolysis analysis indicate that magnesium induces conformational changes in the protein that promote a more rigid, but less active, form of the enzyme. The results shown here provide new insights into the catalytic mechanism of the secretion ATPase superfamily. © 2012 by The American Society for Biochemistry and Molecular Biology, Inc.
2013-09-06T10:01:03Z
2013-09-06T10:01:03Z
2012
2013-09-06T10:01:04Z
artículo
Journal of Biological Chemistry 287(21): 17408-17414 (2012)
http://hdl.handle.net/10261/81579
10.1074/jbc.M112.357905
22467878
eng
closedAccess
American Society for Biochemistry and Molecular Biology