organization and sequences of phydroxybenzaldehyde dehydrogenase and other plasmidencoded genes for early enzymes of the pcresol degradative pathway in pseudomonas putida ncimb 9866 and 9869 the gene designated pcha encoding the aldehyde dehydrogenase that is required to metabolise the phydroxybenzaldehyde produced by the degradation of pcresol in pseudomonas putida ncimb 9866 and 9869 has been identified on plasmids pra4000 and pra500 respectively the gene lies immediately upstream of the pchc and pchf genes encoding the subunits of pcresol methylhydroxylase pcmh the preceeding enzyme in the pcresol degradative pathway in pra500 the latter genes are followed by the genes encoding the alpha pcag and beta pcah subunits of protocatechuate34dioxygenase whereas in pra4000 the genes encoding pcmh are followed by an open reading frame encoding a protein that is similar to the maturaserelated protein of p alcaligenes a gene designated pchx that encodes a protein of unknown function was identified between the pchc and pchf genes in both plasmids