HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Zittle, C. A. Search for Related Content PubMed Articles by Zittle, C. A.

Stabilization of Calcium-Sensitive (_s) Casein by Kappa-Casein: Effect of Chymotrypsin and Heat on Kappa-Casein

Eastern Regional Research Laboratory¹, Philadelphia 18, Pennsylvania

ABSTRACT

It has been found helpful in studies of the caseins to characterize the calcium-sensitive casein by its quantitative precipitation with calcium chloride (6), and the kappa-casein by its ability to quantitatively stabilize the calcium-sensitive casein so that it does not precipitate with calcium chloride (5). The latter test, which has not been reported in detail, is performed with calcium-sensitive (_s) casein (0.3%), at pH 6.7, with varying amounts of kappa-casein, with a 0.020 M concentration of calcium chloride. The test is set up in 15-ml. centrifuge tubes; total volume of the test mixture is 10.0 ml. A 2% solution of the _s-casein at pH 7.8 is used; subsequent addition of calcium chloride brings the pH of the mixture to the desired pH of 6.7. The solution of ^s-casein (30 to 34 mg.) is added to the tubes, followed by the required volumes of water, and amounts of kappa-casein such that the kappa/_s ratios vary from about 0.03 to 0.12.

¹ Eastern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.