The reaction between elastase and elastic tissue. 2. Preparation and properties of the enzyme

Abstract

Revised curves relating activity of the enzyme to pH were obtained for elastase. The optimum pH range was 8.7-9.2. When adequately buffered, the enzyme is capable of dissolving elastic tissue from 3 sources with equal efficiency at this pH; however, the products of the reaction are not the same. Increasing amounts of sulfuric acid are released from aortic preparations, especially above an initial pH of 9.8, while smaller amounts are liberated from ox ligament. Evidence is advanced that elastase consists of 2 enzymes which act on 2 components of an elastic tissue preparation which is itself dual in nature. The optimum pH of the 2nd enzyme which uses alkali-treated elastic tissue as substrate lies in the range 7.8-8.1.