2H99

Crystal structure of the effector binding domain of a BenM variant (R156H,T157S)

2H99 の概要

• エントリーDOI: 10.2210/pdb2h99/pdb
• 関連するPDBエントリー: 2F6P 2F78 2F7A 2F7B 2F8D 2F97 2H98 2H9B 2H9Q
• 分子名称: HTH-type transcriptional regulator benM, SULFATE ION, ACETATE ION, ... (6 entities in total)
• 機能のキーワード: lttr, benm, transcriptional regulation, catm, transcription
• 由来する生物種: Acinetobacter sp.
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 72127.00

構造登録者

Ezezika, O.C.,Craven, S.H.,Neidle, E.L.,Momany, C. (登録日: 2006-06-09, 公開日: 2007-06-26, 最終更新日: 2023-08-30)

主引用文献

Craven, S.H.,Ezezika, O.C.,Haddad, S.,Hall, R.A.,Momany, C.,Neidle, E.L.
Inducer responses of BenM, a LysR-type transcriptional regulator from Acinetobacter baylyi ADP1.
Mol.Microbiol., 72:881-894, 2009

PubMed Abstract: BenM and CatM control transcription of a complex regulon for aromatic compound degradation. These Acinetobacter baylyi paralogues belong to the largest family of prokaryotic transcriptional regulators, the LysR-type proteins. Whereas BenM activates transcription synergistically in response to two effectors, benzoate and cis,cis-muconate, CatM responds only to cis,cis-muconate. Here, site-directed mutagenesis was used to determine the physiological significance of an unexpected benzoate-binding pocket in BenM discovered during structural studies. Residues in BenM were changed to match those of CatM in this hydrophobic pocket. Two BenM residues, R160 and Y293, were found to mediate the response to benzoate. Additionally, alteration of these residues caused benzoate to inhibit activation by cis,cis-muconate, positioned in a separate primary effector-binding site of BenM. The location of the primary site, in an interdomain cleft, is conserved in diverse LysR-type regulators. To improve understanding of this important family, additional regulatory mutants were analysed. The atomic-level structures were characterized of the effector-binding domains of variants that do not require inducers for activation, CatM(R156H) and BenM(R156H,T157S). These structures clearly resemble those of the wild-type proteins in their activated muconate-bound complexes. Amino acid replacements that enable activation without effectors reside at protein interfaces that may impact transcription through effects on oligomerization.

PubMed: 19400783
DOI: 10.1111/j.1365-2958.2009.06686.x

実験手法

X-RAY DIFFRACTION (1.85 Å)