4-hydroxybenzoate uptake in an isolated soil Acinetobacter sp.

The isolated soil bacteria Acinetobacter strain BEM2 is able to utilize som e xenobiotic aromatic compounds as a carbon source. In this study the metab olism of 4-hydroxybenzoate (4-HBA) by strain BEM2 was characterized. Degrad ation involved a meta-cleavage pathway yielding 3,4-dihydroxybenzoate (3,4- DHBA) as an intermediate and CO2 as the principal product from the C atoms in the aromatic ring. 4-HBA uptake was studied, and the kinetic parameters were determined. The uptake was shown to be directly coupled to ATP hydroly sis and its synthesis, according to the Mitchell chemiosmotic hypothesis.