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 splits proteins into water-soluble fragments called peptones. Although this ordinarily occurs in the stomach, it can be duplicated in a large reaction vessel on a commercial basis. Partial digestion by pepsin can be used in food applicationsâfor instance, in the processing of soy protein and gelatin.
5 Some good substrates of pepsin areZ-L-tyrosyl-L-phenylalanine, Z-L-glutamyl-L-tyrosine,or Z-L-methionyl-L-tyrosine. Amidation of theC-terminal carboxyl group prevents hydrolysis bypepsin. 5,6 Pepsin is commonly used in the preparation of Fabfragments from antibodies. The optimal pH for thepepsin reaction is 1.5-2.5, which will not be detrimentalto the antibody, if it is not exposed for long durations tothe low pH. Solutions should be adjusted to neutralpH for storage. The control of pepsin digestion ofantibodies has been reported.