REGULATION OF BENZOATE-COA LIGASE IN RHODOPSEUDOMONAS-PALUSTRIS

The first step in the anaerobic pathway of benzoate degradation by Rhodopseudomonas palustris is catalyzed by benzoate-coenzyme A ligase. To study factors influencing the synthesis of this enzyme, a polyclonal antiserum was prepared and used in immunoblot assays. Benzoate-CoA ligase was synthesized when cells were grown with benzoate, as well as with hydroxyl- and methyl-substituted benzoates. Partially reduced alicyclic compounds proposed to be intermediates in the benzoate pathway also induced benzoate-CoA ligase. Ligase synthesis was repressed by oxygen. The diversity of inducers is consistent with the observation that benzoate is a central intermediate in the degradation of a variety of aromatic acids with more complex structures.