6izw

From Proteopedia
Jump to navigation Jump to search

Myxococcus xanthus MglA bound to GTP-gamma-S and MglBMyxococcus xanthus MglA bound to GTP-gamma-S and MglB

Structural highlights

6izw is a 3 chain structure with sequence from Myxococcus xanthus DK 1622. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 2.4Å
Ligands:, , ,
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

MGLA_MYXXD Required for multicellular development and for both mechanisms of gliding: social (S) and adventurous (A) motility. Acts as an intracellular switch to coordinate A and S motilities. Controls the direction of gliding and gliding speed.[1] [2]

Publication Abstract from PubMed

Mutual gliding motility A (MglA), a small Ras-like GTPase; Mutual gliding motility B (MglB), its GTPase activating protein (GAP); and Required for Motility Response Regulator (RomR), a protein that contains a response regulator receiver domain, are major components of a GTPase-dependent biochemical oscillator that drives cell polarity reversals in the bacterium Myxococcus xanthus. We report the crystal structure of a complex of M. xanthus MglA and MglB, which reveals that the C-terminal helix (Ct-helix) from one protomer of the dimeric MglB binds to a pocket distal to the active site of MglA. MglB increases the GTPase activity of MglA by reorientation of key catalytic residues of MglA (a GAP function) combined with allosteric regulation of nucleotide exchange by the Ct-helix (a guanine nucleotide exchange factor [GEF] function). The dual GAP-GEF activities of MglB accelerate the rate of GTP hydrolysis over multiple enzymatic cycles. Consistent with its GAP and GEF activities, MglB interacts with MglA bound to either GTP or GDP. The regulation is essential for cell polarity, because deletion of the Ct-helix causes bipolar localization of MglA, MglB, and RomR, thereby causing reversal defects in M. xanthus. A bioinformatics analysis reveals the presence of Ct-helix in homologues of MglB in other bacterial phyla, suggestive of the prevalence of the allosteric mechanism among other prokaryotic small Ras-like GTPases.

Allosteric regulation of a prokaryotic small Ras-like GTPase contributes to cell polarity oscillations in bacterial motility.,Baranwal J, Lhospice S, Kanade M, Chakraborty S, Gade PR, Harne S, Herrou J, Mignot T, Gayathri P PLoS Biol. 2019 Sep 27;17(9):e3000459. doi: 10.1371/journal.pbio.3000459., eCollection 2019 Sep. PMID:31560685[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Spormann AM, Kaiser D. Gliding mutants of Myxococcus xanthus with high reversal frequencies and small displacements. J Bacteriol. 1999 Apr;181(8):2593-601. PMID:10198026
  2. Hartzell P, Kaiser D. Function of MglA, a 22-kilodalton protein essential for gliding in Myxococcus xanthus. J Bacteriol. 1991 Dec;173(23):7615-24. PMID:1938957
  3. Baranwal J, Lhospice S, Kanade M, Chakraborty S, Gade PR, Harne S, Herrou J, Mignot T, Gayathri P. Allosteric regulation of a prokaryotic small Ras-like GTPase contributes to cell polarity oscillations in bacterial motility. PLoS Biol. 2019 Sep 27;17(9):e3000459. doi: 10.1371/journal.pbio.3000459., eCollection 2019 Sep. PMID:31560685 doi:http://dx.doi.org/10.1371/journal.pbio.3000459

6izw, resolution 2.40Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA