The metabolism of biphenyl structures in lignin by the soil bacterium (<i>Pseudomonas paucimobilis</i> SYK‐6)

Abstract

In the soil bacterium ( Pseudomonas paucimobilis SYK‐6), the metabolism of DDVA (biphenyl structure of lignin) and syringic acid (characteristic aromatic ring in hardwood lignin) proceeds via a common intermediate, 3‐methylgallic acid. Protocatechuate is also an intermediate in the metabolism of vanillate and p ‐hydroxybenzoic acid. 3‐Methylgallic acid and protocatechuate are the final aromatic intermediates in lignin microbial degradation and these compounds are substrates of protocatechuate‐4,5‐dioxygenase, which is a key enzyme in obtaining metabolic energy from various structures of lignin in this bacterium.