All rights reserved. Terms of use. Â¨ 37 11 Thermodynamics andThermochemistry Thermodynamics is the study of heat, and how heat can be interconverted into other energyforms. In thermodynamics the system is a specific part of the universe that is being studied,often the system is a chemical reaction. The surroundings are all parts of the universe that arenot the system, typically everything outside the test tube.Â¥ An open system can exchange both energy and matter with its surroundings.
Pepsin has been used as a substitute for rennin in the production of certain cheeses. Treatment of hides. Pepsin is used by the leather industry to remove undesirable traces of remaining tissue, such as hair and fat, from partially processed hides. This enzymatic treatment is called âbatingâ the hides.
Pepsin cleaves Phe1Val, Gln4His, Glu13Ala, Ala14Leu, Leu15Tyr, Tyr16Leu, Gly23Phe, Phe24 in the insulin B chain. Pepsin exhibits maximal activity at pH 2.0 and is inactive at pH 6.5 and above, however pepsin is not fully denatured or irreversibly inactivated until pH 8.0. Therefore, pepsin in solution of up to pH 8.0 can be reactivated upon re-acidification. The stability of pepsin at high pH has significant implications on disease attributed to laryngopharyngeal reflux. Pepsin remains in the larynx following a gastric reflux event. At the mean pH of the laryngopharynx (pH = 6.8) pepsin would be inactive but could be reactivated upon subsequent acid reflux events resulting in damage to local tissues. In laryngopharyngeal reflux. Pepsin is one of the primary causes of mucosal damage during laryngopharyngeal reflux. Pepsin remains in the larynx (pH 6.8) following a gastric reflux event. While enzymatically inactive in this environment, pepsin would remain stable and could be reactivated upon subsequent acid reflux events.