Initial Enzymatic Steps In The Degradation Of Alpha-Pinene ByPseudomonas FluorescensNcimb 11671

The initial steps in the degradation of the bicyclic monoterpene, (–)-alpha-pinene, by a new isolate, Pseudomonas fluorexem NCIMB 11671, are described. Degradation is initiated by an oxygenative attack upon the unsaturated position in the molecule to form the corresponding epoxide, catalysed by a pyridine nucleotide-dependent oxygenase with a narrow substrate specificity. The epoxide undergoes rapid rearrangement and concomitant decyclisation to form a di-unsaturated aldehyde, in which both the cyclobutane and cyclohexane rings of the parent molecule are broken, without the insertion of further oxygen species or the appearance of other intermediate compounds. This represents a new enzymatic mechanism for the disruption of a cyclic ring system.