Crystal structure of Arginine Repressor P115Q mutant from the pathogenic bacterium Corynebacterium pseudotuberculosis bound to arginineCrystal structure of Arginine Repressor P115Q mutant from the pathogenic bacterium Corynebacterium pseudotuberculosis bound to arginine

Structural highlights

6wjp is a 2 chain structure with sequence from Corynebacterium pseudotuberculosis C231. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 1.701Å
Ligands:, , ,
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

D9QA55_CORP2 Regulates arginine biosynthesis genes.[ARBA:ARBA00002095][HAMAP-Rule:MF_00173]

Publication Abstract from PubMed

The arginine repressor (ArgR) regulates the expression of genes involved in arginine biosynthesis. Upon attaining a threshold concentration of arginine in the cytoplasm, the trimeric C-terminal domain of ArgR binds three arginines in a shallow surface cleft and subsequently hexamerizes forming a dimer of trimers containing six Arg co-repressor molecules which are buried at the subunit interfaces. The N-terminal domains of this complex bind to the DNA promoter thereby interrupting the transcription of the genes related to Arg biosynthesis. The crystal structures of the wild type and mutant Pro115Gln ArgR from Corynebacterium pseudotuberculosis determined at 1.7 A demonstrate that a single amino acid substitution switches co-repressor specificity from Tyr to Arg. Molecular dynamics simulations indicate that the first step, i.e., the binding of the co-repressor, occurs in the trimeric state and that Pro115Gln ArgR preferentially binds Arg. It was also shown that, in Pro115 ArgR hexamers, the concomitant binding of sodium ions shifts selectivity to Tyr. Structural data combined with phylogenetic analyses of ArgR from C. pseudotuberculosis suggest that substitutions in the binding pocket at position 115 may alter its specificity for amino acids and that the length of the protein interdomain linker can provide further functional flexibility. These results support the existence of alternative ArgR regulatory mechanisms in this pathogenic bacterium.

A single P115Q mutation modulates specificity in the Corynebacterium pseudotuberculosis arginine repressor.,Mariutti RB, Hernandez-Gonzalez JE, Nascimento AFZ, de Morais MAB, Murakami MT, Carareto CMA, Arni RK Biochim Biophys Acta Gen Subj. 2020 Mar 7;1864(7):129597. doi:, 10.1016/j.bbagen.2020.129597. PMID:32156582[1]

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

See Also

References

  1. Mariutti RB, Hernández-González JE, Nascimento AFZ, de Morais MAB, Murakami MT, Carareto CMA, Arni RK. A single P115Q mutation modulates specificity in the Corynebacterium pseudotuberculosis arginine repressor. Biochim Biophys Acta Gen Subj. 2020 Jul;1864(7):129597. PMID:32156582 doi:10.1016/j.bbagen.2020.129597

6wjp, resolution 1.70Å

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