Date of Award
8-1972
Document Type
Dissertation - Restricted
Degree Name
Doctor of Philosophy (PhD)
Department
Medical
First Advisor
Beatrice Kassell
Second Advisor
Alan Mehler
Third Advisor
Patricia Meitner
Fourth Advisor
John Kay
Fifth Advisor
Albert Girotti
Abstract
Pepsinogens have been isolated from the gastric mucosa of pig, cow, dogfish, and chicken. The mammaliam zymogens are similar in composition, but distinctly different from the dogfish and chicken pepsinogens. Although there ls a great deal of similarity in the compositions of the porcine and bovine zymogens, the compositions are sufficiently different to warrant the study of a third mammalian pepsinogen. The first portion of this dissertation describes the purification and characterization of canine pepsinogen. A comparison is made of the compositions of canine, porcine, and bovine pepsinogens. The pepsins of the pig and cow show marked quantitative differences in their activity towards several substrates, in their resistance to alkali denaturation, and in their stability to temperature inactivation. Comparison of sequences in these pepsins may shed light on the differences between them. The second portion of this dissertation describes the determination of the sequence of a few amino acids of a peptide from the carboxyl terminal region of bovine pepsin. Comparison is made with the corresponding region in porcine pepsin.