Abstract
In the reported investigation, precipitation of proteins in solution of 12-phosphotungstic acid was studied by using thermometric titration technique. In all of the titrations reported the protein was in the concentration range of 2-5 g/l and the titrant was added at a rate of 1. 26 mu equivalent/sec. Photometric measurements of protein concentration were carried out on a Cary 14 recording spectrophotometer. Amperometric measurements were carried out with a Heath polarographic unit. A set of thermometric titration curves of bovine albumin with PTA at acidities ranging from pH 2 to 5 are shown. Most titrations reported here were carried out at pH 1. In general the data correlate quite well with the sum of basic amino acids in the protein. The thermometric titration curves indicate that the first stage of reaction is more exothermic than the second. This may be rationalized by assuming that chloride binding to proteins is exothermic and that the heat of binding PTA to a given site is independent of whether the neighboring sites are vacant or occupied by chloride.
| Original language | English (US) |
|---|---|
| Pages | 457-464 |
| Number of pages | 8 |
| State | Published - Jan 1 1974 |
| Event | Am Chem Soc Symp on Anal Calorimetry, 3rd, Proc - Los Angeles, CA, USA Duration: Mar 30 1974 → Apr 5 1974 |
Other
| Other | Am Chem Soc Symp on Anal Calorimetry, 3rd, Proc |
|---|---|
| City | Los Angeles, CA, USA |
| Period | 3/30/74 → 4/5/74 |