Structure of the GMPPNP-stabilized NG domain complex of the SRP GTPases Ffh and FtsY.

ABSTRACT: Ffh and FtsY are GTPase components of the signal recognition particle co-translational targeting complex that assemble during the SRP cycle to form a GTP-dependent and pseudo twofold symmetric heterodimer. Previously the SRP GTPase heterodimer has been stabilized and purified for crystallographic studies using both the non-hydrolysable GTP analog GMPPCP and the pseudo-transition state analog GDP:AlF4, revealing in both cases a buried nucleotide pair that bridges and forms a key element of the heterodimer interface. A complex of Ffh and FtsY from Thermus aquaticus formed in the presence of the analog GMPPNP could not be obtained, however. The origin of this failure was previously unclear, and it was thought to have arisen from either instability of the analog, or, alternatively, from differ

SUBMITTER: Gawronski-Salerno J 

PROVIDER: S-EPMC2566988 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature