1rq7
From Proteopedia
MYCOBACTERIUM TUBERCULOSIS FTSZ IN COMPLEX WITH GDP
Overview
We report three crystal structures of the Mycobacterium tuberculosis cell division protein FtsZ, as the citrate, GDP, and GTPgammaS complexes, determined at 1.89, 2.60, and 2.08A resolution. MtbFtsZ crystallized as a tight, laterally oriented dimer distinct from the longitudinal polymer observed for alphabeta-tubulin. Mutational data on Escherichia coli FtsZ suggest that this dimer interface is important for proper protofilament and "Z-ring" assembly and function. An alpha-to-beta secondary structure conformational switch at the dimer interface is spatially analogous to, and has many of the hallmarks of, the Switch I conformational changes exhibited by G-proteins upon activation. The presence of a gamma-phosphate in the FtsZ active site modulates the conformation of the "tubulin" loop T3 (spatially analogous to the G-protein Switch II); T3 switching upon gamma-phosphate ligation is directly coupled to the alpha-to-beta switch by steric overlap. The dual conformational switches observed here for the first time in an FtsZ link GTP binding and hydrolysis to FtsZ (and tubulin) lateral assembly and Z-ring contraction, and they are suggestive of an underappreciated functional analogy between FtsZ, tubulin and G-proteins.
About this Structure
1RQ7 is a Single protein structure of sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA.
Reference
Structure of Mycobacterium tuberculosis FtsZ reveals unexpected, G protein-like conformational switches., Leung AK, Lucile White E, Ross LJ, Reynolds RC, DeVito JA, Borhani DW, J Mol Biol. 2004 Sep 17;342(3):953-70. PMID:15342249 Page seeded by OCA on Sat May 3 07:46:57 2008
