1: J Biol Chem  2000 May 12;275(19):14260-3 

The role of the DELSEED motif of the beta subunit in rotation of F1-ATPase.

Hara KY, Noji H, Bald D, Yasuda R, Kinosita K Jr, Yoshida M.

Chemical Resources Laboratory, R-1, Tokyo Institute of Technology, Nagatsuta
4259, Yokohama 226-8503, Japan.

F(1)-ATPase is a rotary motor protein, and ATP hydrolysis generates torque at
the interface between the gamma subunit, a rotor shaft, and the alpha(3)beta(3)
substructure, a stator ring. The region of conserved acidic "DELSEED" motif of
the beta subunit has a contact with gamma subunit and has been assumed to be
involved in torque generation. Using the thermophilic alpha(3)beta(3)gamma
complex in which the corresponding sequence is DELSDED, we replaced each residue
and all five acidic residues in this sequence with alanine. In addition, each of
two conserved residues at the counterpart contact position of gamma subunit was
also replaced. Surprisingly, all of these mutants rotated with as much torque as
the wild-type. We conclude that side chains of the DELSEED motif of the beta
subunit do not have a direct role in torque generation.

PMID: 10799504 [PubMed - indexed for MEDLINE]