ATROPINE METABOLISM BY A PSEUDOMONAS SP - DIAUXIC GROWTH AND OXIDATION OF THE PRODUCTS FROM ESTERASE-MEDIATED CLEAVAGE

Pseudomonas AT3 was isolated by elective culture with atropine as sole carbon source. Growth on atropine involved cleavage of the ester bond and was diauxic, with tropic acid being used in the first phase of growth followed by growth on the accumulated tropine moiety. During growth in N-limited medium, tropic acid was still used preferentially, nitrogen was provided from the tropine and novel keto compounds accumulated in the media. An inducible atropine esterase was synthesized during growth on atropine and, to a lesser extent, during growth on tropic acid and tropine. Organisms harvested from either phase of diauxic growth were able to oxidise tropic acid and atropine. The ability of Pseudomonas AT3 to oxidize tropine was evident only in the second phase of growth and the greater extent of atropine oxidation in this phase reflected the ability to oxidise both cyclic components.