S. Chanama et Rl. Crawford, MUTATIONAL ANALYSIS OF PCPA AND ITS ROLE IN PENTACHLOROPHENOL DEGRADATION BY SPHINGOMONAS (FLAVOBACTERIUM) CHLOROPHENOLICA ATCC-39723, Applied and environmental microbiology, 63(12), 1997, pp. 4833-4838
Sphingomonas (Flavobacterium) chlorophenolica ATCC 39723 degrades pent
achlorophenol (PCP) through a catabolic pathway encoded by multiple ge
nes. One gene required for PCP degradation is pcpA, which encodes info
rmation for a 30-kDa polypeptide, PcpA, found in the periplasm of the
bacterium. The biological role of PcpA has remained unknown. We disrup
ted pcpA by replacing it with a defective copy through homologous reco
mbination. The pcpA recombinant, mutant strains accumulated 2,6-dichlo
rohydroquinone (2,6-DiCH) as a metabolite of PCP. This work confirms t
hat pcpA is essential for degradation of PCP by S. chlorophenolica ATC
C 39723 and suggests that it encodes a protein involved in hydrolytic
dehalogenation of 2,6-DiCH, an already established primary metabolite
of the PCP catabolic pathway.