4r6i

AtxA protein, a virulence regulator from Bacillus anthracis.

spinqualitylabelsall models 4r6i, resolution 2.65Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 4r6i is a 2 chain structure with sequence from Bacillus anthracis str. 'Ames Ancestor'. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: LMT, MSE Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function ATXA_BACAN Publication Abstract from PubMed The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthesis operon. AtxA activity is elevated during growth in media containing glucose and CO2 /bicarbonate, and there is a positive correlation between the CO2 /bicarbonate signal, AtxA activity, and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (His-->Asp) and phosphoablative (His-->Ala) amino acid changes for activity in B. anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (1) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (2) phosphorylation of H379 in PRD2 disrupts dimer formation. The AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism. Crystal structure of Bacillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity.,Hammerstrom TG, Horton LB, Swick MC, Joachimiak A, Osipiuk J, Koehler TM Mol Microbiol. 2014 Nov 17. doi: 10.1111/mmi.12867. PMID:25402841 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA