Degradation of 1,2,3,4-Tetrachlorobenzene by Pseudomonas chlororaphis RW71

AUTOR(ES)

Potrawfke, Thomas

FONTE

American Society for Microbiology

RESUMO

Pseudomonas chlororaphis RW71 mineralized 1,2,3,4-tetrachlorobenzene, a highly recalcitrant pollutant hitherto not known to be degraded by pure cultures, as a sole source of carbon and energy, thereby releasing stoichiometric amounts of chloride. The transient excretion of tetrachlorocatechol in the early growth phase suggests an initial attack by a dioxygenase to form the corresponding dihydrodiol which rearomatizes to the catechol. The activity of chlorocatechol 1,2-dioxygenase in crude cell extracts was found to be extraordinarily high towards 3-chlorocatechol (ratio of 2.6 compared to catechol) and other chlorocatechols, including tetrachlorocatechol, which was transformed at a low but significant rate. Further identification of tetrachloromuconic acid, 2,3,5-trichlorodienelactone, 2,3,5-trichloromaleyl acetic acid, and 2,4-dichloro-3-oxoadipic acid as their methyl esters, together with high specific enzyme activities for chlorinated substrates, implicated a functioning chlorocatechol pathway to be induced during growth.

Documentos Relacionados

• Chlorocatechols Substituted at Positions 4 and 5 Are Substrates of the Broad-Spectrum Chlorocatechol 1,2-Dioxygenase of Pseudomonas chlororaphis RW71
• Degradation of 1,2,4-Trichloro- and 1,2,4,5-Tetrachlorobenzene by Pseudomonas Strains
• Biotransformation of 2,7-Dichloro- and 1,2,3,4-Tetrachlorodibenzo-p-Dioxin by Sphingomonas wittichii RW1
• Microbial Hydroxylation of 5-Anilino-1,2,3,4-Thiatriazole
• Synthesis of new 4-methyl-2-(4-pyridyl)-1,2,3,4-tetrahydroquinolines as potent antifungal compounds