Date of Award:
5-1-1972
Document Type:
Thesis
Degree Name:
Master of Science (MS)
Department:
Biology
Department name when degree awarded
Bacteriology and Public Health
Committee Chair(s)
Carl A. Westby
Committee
Carl A. Westby
Committee
Rex S. Spendlove
Committee
John R. Simmons
Abstract
The regulation of the alternate first enzyme of purine de novo synthesis (ribose-5'-phosphate aminotransferase) has been examined in pur-F 341, a purine-requiring mutant of Salmonella typhimurium deficient in the primary first enzyme (PP-ribose-P amidotransferase, EC 2.4.2.14). The ribose-5'- phosphate aminotransferase is feed-back inhibited by AMP, ADP, GDP and adenosine but not by ATP, GTP, GMP and free adenine. Pyrimidines (except CDP and UDP) and thiamine compounds show no significant inhibitory effect on ribose-5'-phosphate aminotransferase activity. The alternate enzyme seems to be also controlled at the gene-level by one or more intra-cellular purines (repression-derepression). The role of the aminotransferase in relation to the primary enzyme was determined by employing wild type S. typhimurium extract (both enzymes present) in a system where the primary enzyme was rendered inoperable. The substrate requirements of the aminotransferase (ribose-5.'-phosphate and NH4C1) were confirmed.
Recommended Citation
Tsai, Wen-cherng, "The Regulation of Purine Biosynthesis in a Phosphoribosylpyrophosphate Aminotransferase-Deficient Mutant of Salmonella typhimurium" (1972). Biology. 386.
https://digitalcommons.usu.edu/etd_biology/386
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