Document Type



It has become increasingly clear in recent years that some proteins are capable of binding most common anions, and many studies with organic dye anions, detergent anions, and with some inorganic anions have been reported. On the basis of some of these studies Klotz and Urquhart4 have suggested that a "binding index" exists, which can be computed from the amino acid composition of a protein, and which will predict the relative affinity of different proteins for any anion. It would be desirable to test this hypothesis for chloride ion, since this is the most abundant anion in physiological systems. Unfortunately, chloride binding has been measured for only one protein, human serum albumin. The results obtained with this protein were, however, especially interesting in that they showed that an indirect method of computing chloride binding from the effect of chlorides upon the pH of an isoionic protein solution gives results in good agreement with direct determination. Since data on pH changes resulting from salt addition are available in the literature for a few proteins, it becomes possible to compute the extent of chloride binding for these proteins, and this has been done in this paper for egg albumin, beta lactoglobulin, and horse carboxyhemoglobin.

Publication Date


Journal Title

Proceedings of the Iowa Academy of Science





First Page


Last Page



©1950 Iowa Academy of Science, Inc.



File Format




To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.