3FYA

Crystal Structure of an R35A mutant of the Restriction-Modification Controller Protein C.Esp1396I

3FYA の概要

• エントリーDOI: 10.2210/pdb3fya/pdb
• 関連するPDBエントリー: 3CLC
• 分子名称: Regulatory protein (1 entity in total)
• 機能のキーワード: transcriptional regulator, helix-turn-helix, restriction-modification, transcription regulator
• 由来する生物種: Enterobacter sp.
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 22648.29

構造登録者

Ball, N.J.,McGeehan, J.E.,Thresh, S.J.,Streeter, S.D.,Kneale, G.G. (登録日: 2009-01-22, 公開日: 2009-08-25, 最終更新日: 2023-09-06)

主引用文献

Ball, N.,Streeter, S.D.,Kneale, G.G.,McGeehan, J.E.
Structure of the restriction-modification controller protein C.Esp1396I.
Acta Crystallogr.,Sect.D, 65:900-905, 2009

PubMed Abstract: The controller protein of the Esp1396I restriction-modification (R-M) system binds differentially to three distinct operator sequences upstream of the methyltransferase (M) and endonuclease (R) genes to regulate the timing of gene expression. The crystal structure of a complex of the protein with two adjacent operator DNA sequences has been reported; however, the structure of the free protein has not yet been determined. Here, the crystal structure of the free protein is reported, with seven dimers in the asymmetric unit. Two of the 14 monomers show an alternative conformation to the major conformer in which the side chains of residues 43-46 in the loop region flanking the DNA-recognition helix are displaced by up to 10 A. It is proposed that the adoption of these two conformational states may play a role in DNA-sequence promiscuity. The two alternative conformations are also found in the R35A mutant structure, which is otherwise identical to the native protein. Comparison of the free and bound protein structures shows a 1.4 A displacement of the recognition helices when the dimer is bound to its DNA target.

PubMed: 19690367
DOI: 10.1107/S0907444909020514

実験手法

X-RAY DIFFRACTION (3 Å)