1L9N

Three-dimensional structure of the human transglutaminase 3 enzyme: binding of calcium ions change structure for activation

1L9N の概要

• エントリーDOI: 10.2210/pdb1l9n/pdb
• 関連するPDBエントリー: 1L9M
• 分子名称: Protein-glutamine glutamyltransferase E3, 2-O-octyl-beta-D-glucopyranose, CALCIUM ION, ... (5 entities in total)
• 機能のキーワード: activation, calcium binding, transglutaminase, transferase
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 154237.11

構造登録者

Ahvazi, B. (登録日: 2002-03-26, 公開日: 2002-05-29, 最終更新日: 2023-08-16)

主引用文献

Ahvazi, B.,Kim, H.C.,Kee, S.H.,Nemes, Z.,Steinert, P.M.
Three-dimensional structure of the human transglutaminase 3 enzyme: binding of calcium ions changes structure for activation.
EMBO J., 21:2055-2067, 2002

PubMed Abstract: Transglutaminase (TGase) enzymes catalyze the formation of covalent cross-links between protein-bound glutamines and lysines in a calcium-dependent manner, but the role of Ca(2+) ions remains unclear. The TGase 3 isoform is widely expressed and is important for epithelial barrier formation. It is a zymogen, requiring proteolysis for activity. We have solved the three-dimensional structures of the zymogen and the activated forms at 2.2 and 2.1 A resolution, respectively, and examined the role of Ca(2+) ions. The zymogen binds one ion tightly that cannot be exchanged. Upon proteolysis, the enzyme exothermally acquires two more Ca(2+) ions that activate the enzyme, are exchangeable and are functionally replaceable by other lanthanide trivalent cations. Binding of a Ca(2+) ion at one of these sites opens a channel which exposes the key Trp236 and Trp327 residues that control substrate access to the active site. Together, these biochemical and structural data reveal for the first time in a TGase enzyme that Ca(2+) ions induce structural changes which at least in part dictate activity and, moreover, may confer substrate specificity.

PubMed: 11980702
DOI: 10.1093/emboj/21.9.2055

実験手法

X-RAY DIFFRACTION (2.1 Å)