An esterase as marker enzyme on the outer membrane of Acinetobacter calcoaceticus

An esterase activity which hydrolyses palmitoyl‐CoA was found in the membrane fraction of Acinetobacter calcoaceticus 69/V. Other tested strains of Acinetobacter also possessed this enzyme activity. The esterase is constitutive, fully active on the surface of intact cells and located on the outer membrane of the bacteria. Besides palmitoyl‐CoA some oxy‐esters and p ‐nitrophenyl palmitate were also hydrolyzed. In contrast triglycerides, short‐chain acyl‐CoA esters (C 2 —C 10 ) and p ‐nitrophenyl acetate were not hydrolyzed. The enzyme activity was not influenced by inhibitors of mammalian esterases.