A novel pathway of aerobic benzoate catabolism in the bacteria Azoarcus evansii and Bacillus stearothermophilus.
The aerobic catabolism of benzoate was studied in the Gram-negative proteobacterium Azoarcus evansii and in the Gram-positive bacterium Bacillus stearothermophilus. In contrast to earlier proposals, benzoate was not converted into hydroxybenzoate or gentisate. Rather, benzoyl-CoA was a product of benzoate catabolism in both microbial species under aerobic conditions in vivo. Benzoyl-CoA was converted into various CoA thioesters by cell extracts of both species in oxygen- and NADPH-dependent reactions. Using [ring-(13)C(6)]benzoyl-CoA as substrate, cis-3,4-[2,3,4,5,6-(13)C(5)]dehydroadipyl-CoA, trans-2,3-[2,3,4,5,6-(13)C(5)]dehydroadipyl-CoA, the 3,6-lactone of 3-[2,3,4,5,6-(13)C(5)]hydroxyadipyl-CoA, and 3-[2,3,4,5,6-(13)C(5)]hydroxyadipyl-CoA were identified as products by NMR spectroscopy. A protein mixture of A. evansii transformed [ring-(13)C(6)]benzoyl-CoA in an NADPH- and oxygen-dependent reaction into 6-[2,3,4,5,6-(13)C(5)]hydroxy-3-hexenoyl-CoA. The data suggest a novel aerobic pathway of benzoate catabolism via CoA intermediates leading to beta-ketoadipyl-CoA, an intermediate of the known beta-ketoadipate pathway.
Zaar
A
A
Institut für Biologie II, Mikrobiologie, Universität Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany.
Eisenreich
W
W
Bacher
A
A
Fuchs
G
G
D000214:Acyl Coenzyme A / Q000378:metabolism; D000332:Aerobiosis; D020627:Azoarcus / Q000378:metabolism*; D001565:Benzoates / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005841:Gentisates / Q000378:metabolism; D001411:Geobacillus stearothermophilus / Q000378:metabolism*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical
D000214:Acyl Coenzyme A; D001565:Benzoates; D005841:Gentisates; C037817:benzoyl-coenzyme A