3t12

MglA in complex with MglB in transition state

spinqualitylabelsall models 3t12, resolution 2.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3t12 is a 3 chain structure with sequence from Thermus thermophilus HB8. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.2Å Ligands: ALF, GDP, MG Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function Q5SJ82_THET8 Publication Abstract from PubMed The bacterium Myxococcus xanthus uses a G protein cycle to dynamically regulate the leading/lagging pole polarity axis. The G protein MglA is regulated by its GTPase-activating protein (GAP) MglB, thus resembling Ras family proteins. Here, we show structurally and biochemically that MglA undergoes a dramatic, GDP-GTP-dependent conformational change involving a screw-type forward movement of the central beta2-strand, never observed in any other G protein. This movement and complex formation with MglB repositions the conserved residues Arg53 and Gln82 into the active site. Residues required for catalysis are thus not provided by the GAP MglB, but by MglA itself. MglB is a Roadblock/LC7 protein and functions as a dimer to stimulate GTP hydrolysis in a 2:1 complex with MglA. In vivo analyses demonstrate that hydrolysis mutants abrogate Myxococcus' ability to regulate its polarity axis changing the reversal behaviour from stochastic to oscillatory and that both MglA GTPase activity and MglB GAP catalysis are essential for maintaining a proper polarity axis. Structural analysis of the Ras-like G protein MglA and its cognate GAP MglB and implications for bacterial polarity.,Miertzschke M, Koerner C, Vetter IR, Keilberg D, Hot E, Leonardy S, Sogaard-Andersen L, Wittinghofer A EMBO J. 2011 Aug 16. doi: 10.1038/emboj.2011.291. PMID:21847100 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Gliding protein

Proteopedia Page Contributors and Editors (what is this?)

OCA