Chemistry Reference
In-Depth Information
Fig. 9.23
Biocatalytic routes for the
removal of halide from chlorinated
aromatic compounds.
OH
O
OH
mono-oxygenase
O
Cl
Cl
Cl
Cl
Cl
Cl
- HCl
Cl
Cl
Cl
Cl
Cl
Cl
HO
Cl
O
Cl
Fig. 9.24
Monooxygenase-catalysed
dehalogenation of pentachlorophenol.
fungus
Cunninghamella elegans
(Fig. 9.25), where
a range of metabolic products is obtained in which
the chlorine substituent of the substrate remains
intact [85].
processing in non-environmental settings in a con-
trolled and reproducible manner. The latter technol-
ogy is applicable, for example, to the destruction of
organophosphate pesticides and the organophos-
phate nerve gases stockpiled from military opera-
tions. An immobilised suspension of genetically
constructed
Escherichia coli
with an organophospho-
rus hydrolase enzyme anchored on the outer cell
surface can efficiently hydrolyse a series of
organophosphate esters, including paraoxon, dia-
zonon and methylparathion, during repeated cycles
over long periods [87].
Miscellaneous pollutants
The detoxification of pesticides by microbial enzymes
represents a major route for their removal from the
environment [86], and in a logical extension of this
area methods have been developed for the detoxifi-
cation of specific classes of pesticides by biocatalytic
