title: Novel degradative pathway of 4-nitrobenzoate in Comamonas acidovorans NBA-10.
abstract: A Comamonas acidovorans strain, designated NBA-10, was isolated on 4-nitrobenzoate as sole carbon and energy source. When grown on 4-nitrobenzoate, it was simultaneously adapted to 4-nitrosobenzoate and 4-hydroxylaminobenzoate but not to 4-hydroxybenzoate or 4-aminobenzoate. In cell extracts with NADPH present, 4-nitrobenzoate was degraded to 4-hydroxylaminobenzoate and 3,4-dihydroxybenzoate. Partial purification of the 4-nitrobenzoate reductase revealed that 4-nitrobenzoate is degraded via 4-nitrosobenzoate to 4-hydroxylamino-benzoate. The substrate specificity of the enzyme was narrow and NADPH was 15 times more effective as a cofactor than NADH. The results provide evidence for a novel pathway for aerobic degradation of 4-nitrobenzoate, since neither 4-hydroxybenzoate nor 4-aminobenzoate were involved in the degradative pathway.
authors.affiliation: Department of Food Science, Agricultural University, Wageningen, The Netherlands.
authors.forename: P E
authors.initials: PE
authors.lastname: Groenewegen
authors.forename: P
authors.initials: P
authors.lastname: Breeuwer
authors.forename: J M
authors.initials: JM
authors.lastname: van Helvoort
authors.forename: A A
authors.initials: AA
authors.lastname: Langenhoff
authors.forename: F P
authors.initials: FP
authors.lastname: de Vries
authors.forename: J A
authors.initials: JA
authors.lastname: de Bont
mesh_terms: D007700:Kinetics; D009579:Nitrobenzoates / Q000378:metabolism*; D010088:Oxidoreductases / Q000302:isolation & purification / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D011549:Pseudomonas / Q000254:growth & development / Q000378:metabolism*; D013057:Spectrum Analysis
chemical_list: D009579:Nitrobenzoates; D010088:Oxidoreductases; C021870:4-nitrobenzoate reductase; D010100:Oxygen