3KS3

High resolution structure of Human Carbonic Anhydrase II at 0.9 A

3KS3 の概要

• エントリーDOI: 10.2210/pdb3ks3/pdb
• 分子名称: Carbonic anhydrase 2, ZINC ION, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: high resolution, carbonic anhydrase, short hydrogen bond, lyase
• 由来する生物種: Homo sapiens (human)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 29446.57

構造登録者

Avvaru, B.S. (登録日: 2009-11-20, 公開日: 2010-01-26, 最終更新日: 2024-02-21)

主引用文献

Avvaru, B.S.,Kim, C.U.,Sippel, K.H.,Gruner, S.M.,Agbandje-McKenna, M.,Silverman, D.N.,McKenna, R.
A short, strong hydrogen bond in the active site of human carbonic anhydrase II.
Biochemistry, 49:249-251, 2010

PubMed Abstract: The crystal structure of human carbonic anhydrase II (HCA II) obtained at 0.9 A resolution reveals that a water molecule, termed deep water, Dw, and bound in a hydrophobic pocket of the active site forms a short, strong hydrogen bond with the zinc-bound solvent molecule, a conclusion based on the observed oxygen-oxygen distance of 2.45 A. This water structure has similarities with hydrated hydroxide found in crystals of certain inorganic complexes. The energy required to displace Dw contributes in significant part to the weak binding of CO(2) in the enzyme-substrate complex, a weak binding that enhances k(cat) for the conversion of CO(2) into bicarbonate. In addition, this short, strong hydrogen bond is expected to contribute to the low pK(a) of the zinc-bound water and to promote proton transfer in catalysis.

PubMed: 20000378
DOI: 10.1021/bi902007b

実験手法

X-RAY DIFFRACTION (0.9 Å)