Self-association of proteins. 1. Self-association of .alpha.-chymotrypsin at pH 8.3 and ionic strength 0.05.

Pandit, M. W. and Narasinga Rao, M. S. (1974) Self-association of proteins. 1. Self-association of .alpha.-chymotrypsin at pH 8.3 and ionic strength 0.05. Biochemica Biophysica Acta, 371. pp. 211-218.

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Abstract

The self-association of a-chymotrypsin at pH 8.3 and p = 0.05 was studied by measuring the weight-average molecular weight by the Archibald method and the sedimentation coefficient as a function of protein concentration. Considerable autolysis of the protein occurred under the experimental conditions used. A method was devised to measure the extent of autolysis.,The molecular weight data were corrected for the presence of the autolysis product(s) which itself did not undergo self-association. An analysis of the experimental molecular weight data for various models of self-association showed that indefinite self-association model with nonideality term set to zero fitted the data the best. However, analysis of the sedimentation coefficient data showed that a monomerhexamer equilibrium, without any intermediate species, fitted the data the best. Pressure in sedimentation velocity experiments did not affect SPO,., values but affected the shape of the velocity patterns. The addition of autolysis product(s) of the enzyme did not affect self-association as revealed by molecular weight data, but affected the sedimentation velocity patterns.

Item Type:	Article
Uncontrolled Keywords:	self-association, alpha-chymotrypsin, proteins
Subjects:	600 Technology > 08 Food technology > 16 Nutritive value > 03 Proteins
Divisions:	Protein Chemistry and Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	05 Mar 2018 09:47
Last Modified:	05 Mar 2018 09:47
URI:	http://ir.cftri.res.in/id/eprint/5326

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