Skip to main content
The Journal of General Physiology logoLink to The Journal of General Physiology
. 1940 Jan 20;23(3):301–308. doi: 10.1085/jgp.23.3.301

PHYSICOCHEMICAL PROPERTIES OF THE PROTEOLYTIC ENZYME FROM THE LATEX OF THE MILKWEED, ASCLEPIAS SPECIOSA TORR. SOME COMPARISONS WITH OTHER PROTEASES

III. KINETICS OF THE HEAT INACTIVATION OF PAPAIN, BROMELIN, AND ASCLEPAIN

Theodore Winnick 1, Alva R Davis 1, David M Greenberg 1
PMCID: PMC2237929  PMID: 19873156

Abstract

1. The rates of heat inactivation of papain, bromelin, and asclepain were determined at several different temperatures. Papain was by far the most resistant to heat. 2. The destruction of papain at 75–83° and bromelin at 55–70° followed the course of a first order reaction, except that for longer times of heating, bromelin (at 60–70°) was inactivated more rapidly than the first order equation required. 3. The rate of inactivation of asclepain at 55–70° followed the second order equation. 4. The critical thermal increments of inactivation of papain and bromelin, calculated with the van't Hoff-Arrhenius equation, were of the same high order that has been found for protein denaturation. The increment for asclepain was somewhat lower.

Full Text

The Full Text of this article is available as a PDF (426.9 KB).


Articles from The Journal of General Physiology are provided here courtesy of The Rockefeller University Press

RESOURCES