TY - JOUR
T1 - XThe ClpXP protease unfolds substrates using a constant rate of pulling but different gears
AU - Sen, Maya
AU - Maillard, Rodrigo A.
AU - Nyquist, Kristofor
AU - Rodriguez-Aliaga, Piere
AU - Pressé, Steve
AU - Martin, Andreas
AU - Bustamante, Carlos
N1 - Funding Information:
We thank Shixin Liu, Gheorghe Chistol, Ninning Liu, Christian Kaiser, and Mary Matyskiela for helpful discussions. M.S. and K.N. acknowledge support from the NSF Graduate Research Fellowship. This research was supported in part by the Searle Scholars Program (A.M.), the NIH grant R01-GM094497-01A1 (A.M.), the NIH grant R01-GM0325543 (C.B.), the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under contract no. DE-AC02-05CH11231 (C.B.), and the Howard Hughes Medical Institute (C.B.).
PY - 2013/10/24
Y1 - 2013/10/24
N2 - ATP-dependent proteases are vital to maintain cellular protein homeostasis. Here, we study the mechanisms of force generation and intersubunit coordination in the ClpXP protease from E. coli to understand how these machines couple ATP hydrolysis to mechanical protein unfolding. Single-molecule analyses reveal that phosphate release is the force-generating step in the ATP-hydrolysis cycle and that ClpXP translocates substrate polypeptides in bursts resulting from highly coordinated conformational changes in two to four ATPase subunits. ClpXP must use its maximum successive firing capacity of four subunits to unfold stable substrates like GFP. The average dwell duration between individual bursts of translocation is constant, regardless of the number of translocating subunits, implying that ClpXP operates with constant "rpm" but uses different "gears."
AB - ATP-dependent proteases are vital to maintain cellular protein homeostasis. Here, we study the mechanisms of force generation and intersubunit coordination in the ClpXP protease from E. coli to understand how these machines couple ATP hydrolysis to mechanical protein unfolding. Single-molecule analyses reveal that phosphate release is the force-generating step in the ATP-hydrolysis cycle and that ClpXP translocates substrate polypeptides in bursts resulting from highly coordinated conformational changes in two to four ATPase subunits. ClpXP must use its maximum successive firing capacity of four subunits to unfold stable substrates like GFP. The average dwell duration between individual bursts of translocation is constant, regardless of the number of translocating subunits, implying that ClpXP operates with constant "rpm" but uses different "gears."
UR - http://www.scopus.com/inward/record.url?scp=84886776909&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84886776909&partnerID=8YFLogxK
U2 - 10.1016/j.cell.2013.09.022
DO - 10.1016/j.cell.2013.09.022
M3 - Article
C2 - 24243020
AN - SCOPUS:84886776909
SN - 0092-8674
VL - 155
SP - 636
JO - Cell
JF - Cell
IS - 3
ER -