Catabolism of 2,4,5-trimethyoxybenzoic acid and 3-methoxycrotonic acid

4-Methoxygentisic acid was an intermediate formed when Arthrobacter degraded, 2,4,5-trimethoxybenzoic acid. Isolates of Pseudomonas and Arthrobacter from soil grew at the expense of 3-methoxycrotonic acid. Evidence is presented that enzymatic hydration, with elimination of methanol, accounted for replacement of the methoxyl group of 3-methoxycrotonic acid and also of one methoxyl group of 2,4,5-trimethoxybenzoic acid.