2AGM

Solution structure of the R-module from AlgE4

2AGM の概要

• エントリーDOI: 10.2210/pdb2agm/pdb
• NMR情報: BMRB: 6390
• 分子名称: Poly(beta-D-mannuronate) C5 epimerase 4 (1 entity in total)
• 機能のキーワード: parallel beta-roll, isomerase
• 由来する生物種: Azotobacter vinelandii
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 16976.01

構造登録者

Aachmann, F.L.,Svanem, B.I.,Guntert, P.,Petersen, S.B.,Valla, S.,Wimmer, R. (登録日: 2005-07-27, 公開日: 2006-01-10, 最終更新日: 2024-05-15)

主引用文献

Aachmann, F.L.,Svanem, B.I.,Guntert, P.,Petersen, S.B.,Valla, S.,Wimmer, R.
NMR structure of the R-module: a parallel beta-roll subunit from an Azotobacter vinelandii mannuronan C-5 epimerase.
J.Biol.Chem., 281:7350-7356, 2006

PubMed Abstract: In the bacterium Azotobacter vinelandii, a family of seven secreted and calcium-dependent mannuronan C-5 epimerases (AlgE1-7) has been identified. These epimerases are responsible for the epimerization of beta-d-mannuronic acid to alpha-l-guluronic acid in alginate polymers. The epimerases consist of two types of structural modules, designated A (one or two copies) and R (one to seven copies). The structure of the catalytically active A-module from the smallest epimerase AlgE4 (consisting of AR) has been solved recently. This paper describes the NMR structure of the R-module from AlgE4 and its titration with a substrate analogue and paramagnetic thulium ions. The R-module folds into a right-handed parallel beta-roll. The overall shape of the R-module is an elongated molecule with a positively charged patch that interacts with the substrate. Titration of the R-module with thulium indicated possible calcium binding sites in the loops formed by the nonarepeat sequences in the N-terminal part of the molecule and the importance of calcium binding for the stability of the R-module. Structure calculations showed that calcium ions can be incorporated in these loops without structural violations and changes. Based on the structure and the electrostatic surface potential of both the A- and R-module from AlgE4, a model for the appearance of the whole protein is proposed.

PubMed: 16407237
DOI: 10.1074/jbc.M510069200

実験手法

SOLUTION NMR