|
type |
Journal Article |
authors |
Jann A, Stalon V, Wauven CV, Leisinger T, Haas D. |
title |
N-Succinylated intermediates in an arginine catabolic pathway of Pseudomonas aeruginosa |
journal |
Proc Natl Acad Sci U S A |
Activity |
2.6.1.81 |
sel |
unselected |
ui |
16593724 |
year |
(1986) |
volume |
83 |
number |
13 |
pages |
4937-4941 |
| |
abstract |
Arginine-nonutilizing (aru) mutants of Pseudomonas aeruginosa strain PAO converted L-arginine to N(2)-succinylarginine or N-succinylglutamate, which were identified by high-voltage electrophoresis and HPLC. Addition of aminooxyacetate, an inhibitor of pyridoxal phosphate-dependent enzymes, to resting cells of the wild-type PAO1 in arginine medium led to the accumulation of N(2)-succinylornithine. Enzyme assays with crude P. aeruginosa extracts established the following pathway: L-arginine + succinyl-CoA --> N(2)-succinylarginine --> N(2)-succinylornithine --> N_succinylglutamate 5-semialdehyde --> N-succinylglutamate --> succinate + glutamate. Succinyl-CoA may be regenerated from glutamate via 2-ketoglutarate. L-Arginine induced the enzymes of the pathway, and succinate caused catabolite repression. Purified N(2)-acetylornithine 5-aminotransferase (N(2)-acetyl-L-ornithine: 2-oxoglutarate aminotransferase, EC 2.6.1.11), an arginine biosynthetic enzyme, efficiently transaminated N(2)-succinylornithine; this explains the enzyme's dual role in arginine biosynthesis and catabolism. The succinylarginine pathway enables P. aeruginosa to utilize arginine efficiently as a carbon source under aerobic conditions, whereas the other three arginine catabolic pathways previously established in P. aeruginosa fulfill different functions. |
last changed |
2007/12/17 10:37 |
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