1M22

X-ray structure of native peptide amidase from Stenotrophomonas maltophilia at 1.4 A

1M22 の概要

• エントリーDOI: 10.2210/pdb1m22/pdb
• 関連するPDBエントリー: 1M21
• 分子名称: peptide amidase, 4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID (3 entities in total)
• 機能のキーワード: eleven-stranded beta sheet, covered double layers of alpha helices on top and bottom, hydrolase
• 由来する生物種: Stenotrophomonas maltophilia
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 107567.21

構造登録者

Labahn, J.,Neumann, S.,Buldt, G.,Kula, M.-R.,Granzin, J. (登録日: 2002-06-21, 公開日: 2002-10-16, 最終更新日: 2024-03-13)

主引用文献

Labahn, J.,Neumann, S.,Buldt, G.,Kula, M.-R.,Granzin, J.
An alternative mechanism for amidase signature enzymes
J.MOL.BIOL., 322:1053-1064, 2002

PubMed Abstract: The peptide amidase from Stenotrophomonas maltophilia catalyses predominantly the hydrolysis of the C-terminal amide bond in peptide amides. Peptide bonds or amide functions in amino acid side-chains are not hydrolysed. This specificity makes peptide amidase (Pam) interesting for different biotechnological applications. Pam belongs to the amidase signature (AS) family. It is the first protein within this family whose tertiary structure has been solved. The structure of the native Pam has been determined with a resolution of 1.4A and in complex with the competitive inhibitor chymostatin at a resolution of 1.8A. Chymostatin, which forms acyl adducts with many serine proteases, binds non-covalently to this enzyme.Pam folds as a very compact single-domain protein. The AS sequence represents a core domain that is covered by alpha-helices. This AS domain contains the catalytic residues. It is topologically homologous to the phosphoinositol phosphatase domain. The structural data do not support the recently proposed Ser-Lys catalytic dyad mechanism for AS enzymes. Our results are in agreement with the role of Ser226 as the primary nucleophile but differ concerning the roles of Ser202 and Lys123: Ser202, with direct contact both to the substrate molecule and to Ser226, presumably serves as an acid/bases catalyst. Lys123, with direct contact to Ser202 but no contact to Ser226 or the substrate molecule, most likely acts as an acid catalyst.

PubMed: 12367528
DOI: 10.1016/S0022-2836(02)00886-0

実験手法

X-RAY DIFFRACTION (1.4 Å)