Cod (Gadus morhua) trypsin heat inactivation: A reaction kinetics study

被引：6

作者：

Amiza, MA ^{[1
]}

Galani, D ^{[1
]}

OwusuApenten, RK ^{[1
]}

机构：

[1] UNIV LEEDS,PROCTER DEPT FOOD SCI,LEEDS LS2 9JT,W YORKSHIRE,ENGLAND

来源：

JOURNAL OF FOOD BIOCHEMISTRY | 1997年 / 21卷 / 04期

关键词：

D O I：

10.1111/j.1745-4514.1997.tb00209.x

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

The heat inactivation of cod (Gadus morhua) trypsin was examined at 40-55C by nonlinear regression (NLR) analysis according to 1st-order, n-th order, or consecutive reaction kinetics. At 40C Cod trypsin was inactivated by a 2nd-order reaction; n = 2 (+/-0.014) with a pseudo rate constant (k') of 6.46 (+/-0.04) x 10(-4) (s(-1)). The order of reaction decreased with increasing temperature; n = 1.54 (+/-0.003) at 45C, n = 0.8 (+/-0.005) at 50C or n = 0.64 (+/-0.014) at 55C. At 45-55C the consecutive model also indicated Ist-order inactivation kinetics. SDS-PAGE analysis showed that with progressive heating the concentration of cod trypsin decreased and there was an appearance of lower molecular weight polypeptides. The results are consistent with a heat inactivation process involving trypsin autolysis. A mechanism for cod trypsin heat inactivation is proposed which accounts for the observed 1st-order or 2nd-order reaction kinetics as limiting cases.

引用

页码：273 / 288

页数：16

共 23 条

[21] ON THE ROLE OF REVERSIBLE DENATURATION (UNFOLDING) IN THE IRREVERSIBLE THERMAL INACTIVATION OF ENZYMES [J].

ZALE, SE ;

KLIBANOV, AM .

BIOTECHNOLOGY AND BIOENGINEERING, 1983, 25 (09) :2221-2230

[22] WHY DOES RIBONUCLEASE IRREVERSIBLY INACTIVATE AT HIGH-TEMPERATURES [J].

ZALE, SE ;

KLIBANOV, AM .

BIOCHEMISTRY, 1986, 25 (19) :5432-5444

[23] MECHANISMS OF IRREVERSIBLE THERMOINACTIVATION OF ENZYMES [J].

ZALE, SE ;

KLIBANOV, AM .

ANNALS OF THE NEW YORK ACADEMY OF SCIENCES, 1984, 434 (DEC) :20-26

← 1 2 3 →