6WJP

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

6WJP の概要

• エントリーDOI: 10.2210/pdb6wjp/pdb
• 関連するPDBエントリー: 6WJO
• 分子名称: Arginine repressor, ARGININE, ACETATE ION, ... (6 entities in total)
• 機能のキーワード: enzyme specificity, dna binding protein
• 由来する生物種: Corynebacterium pseudotuberculosis (strain C231)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 18562.03

構造登録者

Nascimento, A.F.Z.,Hernandez-Gonzalez, J.E.,de Morais, M.A.B.,Murakami, M.T.,Carareto, C.M.A.,Arni, R.K.,Mariutti, R.B. (登録日: 2020-04-14, 公開日: 2020-04-22, 最終更新日: 2023-10-18)

主引用文献

Mariutti, R.B.,Hernandez-Gonzalez, J.E.,Nascimento, A.F.Z.,de Morais, M.A.B.,Murakami, M.T.,Carareto, C.M.A.,Arni, R.K.
A single P115Q mutation modulates specificity in the Corynebacterium pseudotuberculosis arginine repressor.
Biochim Biophys Acta Gen Subj, 1864:129597-, 2020

PubMed Abstract: 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 Å 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.

PubMed: 32156582
DOI: 10.1016/j.bbagen.2020.129597

実験手法

X-RAY DIFFRACTION (1.701 Å)