The production and secreton of digestive enzymes in the purple seastarPisaster ochraceus

✍ Scribed by G. W. Barnier; M. V. Sheehan; D. C. Williams

• Publisher: Springer-Verlag
• Year: 1975
• Tongue: English
• Weight: 435 KB
• Volume: 29
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00391852

✦ Synopsis

The purple seastar Pisaster ochraceus contains clearly measurable protease and amylase activity. Centrifuged supernatants of pyloric caeca homogenates undergo a spontaneous threefold increase in protease activity when incubated under toluene for 50 h at 25OC. Amylase activity remains nearly constant over this period. Bovine trypsin at a I to I00 ratio (trypsin to supernatant protein) induces a twofold increase in protease activity over that of the control supernatant while having virtually no effect on amylase activity over the control. The data indicate a specific interaction of trypsin with a protease zymogen rather than a nonspecific hydrolysis of membrane components or vesicles by trypsin. Two percent Triton X-IO0 used as a diluent in place of distilled, deionized water causes a sevenfold increase in protease activity and a twofold increase in amylase activity in pyloric caeca supernatants. The use of Triton as a diluent in the preparation of a stomach-tissue supernatant allows quantitative measurement of both protease and amylase activity in that tissue.