Studies on the regulation of aspartokinase II from Bacillus subtilis

Aspartokinase II from B. subtilis was shown by immunochemical methods to be regulated by degradation in response to starvation of cells for various nutrients. Ammonium starvation induced the fastest aspartokinase II decline (t$\sb{1/2}$ = 65 min), followed by amino acid starvation (t$\sb{1/2}$ = 80 min), and glucose limitation (t$\sb{1/2}$ = 120 min). Pulse-chase experiments demonstrated that aspartokinase II was stable during exponential growth; the synthesis of the enzyme rapidly declined in response to nutrient exhaustion. The degradation of aspartokinase II was interrupted by inhibitors of energy and protein synthesis, but was not changed in a mutant lacking a major intracellular protease. Mutants lacking a normal stringent response displayed only a slight decrease in the rate of aspartokinase II degradation, even though aspartate transcarbamylase was degraded more slowly in the same mutant cells. Cross reaction of anti-aspartokinase II antibodies with a protein similar in sequence to glyceraldehyde-3-phosphate from B. subtilis and E. coli was observed.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biochemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Graves, Lee Michael

Contributors dc:contributor

• Switzer, Robert L.

• Chemistry, Biochemistry

Statement dc:rights

• Copyright 1990 Graves, Lee Michael

Language dc:language

eng

Identifier

AAI9026193
(UMI)AAI9026193

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/22341