1A0J

CRYSTAL STRUCTURE OF A NON-PSYCHROPHILIC TRYPSIN FROM A COLD-ADAPTED FISH SPECIES.

1A0J の概要

• エントリーDOI: 10.2210/pdb1a0j/pdb
• 分子名称: TRYPSIN, CALCIUM ION, SULFATE ION, ... (5 entities in total)
• 機能のキーワード: serine proteinase, trypsin, hydrolase, serine protease
• 由来する生物種: Salmo salar (Atlantic salmon)
• 細胞内の位置: Secreted, extracellular space: P35033
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 96695.96

構造登録者

Schroeder, H.-K.,Willassen, N.P.,Smalaas, A.O. (登録日: 1997-12-01, 公開日: 1999-01-13, 最終更新日: 2024-10-30)

主引用文献

Schroder, H.K.,Willassen, N.P.,Smalas, A.O.
Structure of a non-psychrophilic trypsin from a cold-adapted fish species.
Acta Crystallogr.,Sect.D, 54:780-798, 1998

PubMed Abstract: The crystal structure of cationic trypsin (CST) from the Atlantic salmon (Salmo salar) has been refined at 1.70 A resolution. The crystals are orthorhombic, belong to space group P212121, with lattice parameters a = 65.91, b = 83.11 and c = 154.79 A, and comprise four molecules per asymmetric unit. The structure was solved by molecular replacement with AMoRe and refined with X-PLOR to an R value of 17.4% and Rfree of 21.5% for reflections |F| > 3sigmaF between 8.0 and 1.7 A resolution. The four non-crystallographic symmetry (NCS) related molecules in the asymmetric unit display r.m.s. deviations in the range 0.31-0.74 A for main-chain atoms, with the largest differences confined to two loops. One of these is the calcium-binding loop where the electron-density indicates a calcium ion for only one of the four molecules. In order to find structural rationalizations for the observed difference in thermostability and catalytic efficiency of CST, anionic salmon trypsin (AST) and bovine trypsin (BT), the three structures have been extensively compared. The largest deviations for the superimposed structures occur in the surface loops and particularly in the so-called 'autolysis loop'. Both the salmon enzymes possess a high methionine content, lower overall hydrophobicity and enhanced surface hydrophilicity, compared with BT. These properties have so far been correlated to cold-adaptation features, while in this work it is shown that the non-psychrophilic cationic salmon trypsin shares these features with the psychrophilic anionic salmon trypsin.

PubMed: 9757092
DOI: 10.1107/S0907444997018611

実験手法

X-RAY DIFFRACTION (1.7 Å)