Article

Diversity of anaerobic microbial processes in chlorobenzoate degradation: nitrate, iron, sulfate and carbonate as electron acceptors.

Center for Agricultural Molecular Biology, Cook College, Rutgers, State University of New Jersey, New Brunswick 08903-0231, USA.
Applied Microbiology and Biotechnology (impact factor: 3.42). 11/1995; 43(5):929-36. pp.929-36
Source: PubMed

ABSTRACT The utilization of monochlorobenzoate isomers (2-, 3- and 4-chlorobenzoate) by anaerobic microbial consortia in River Nile sediments was systematically evaluated under denitrifying, Fe-reducing, sulfidogenic and methanogenic conditions. Loss of all three chlorobenzoates was noted in denitrifying cultures; furthermore, the initial utilization of chlorobenzoates was fastest under denitrifying conditions. Loss of 3-chlorobenzoate was seen under all four reducing conditions and the degradation of chlorobenzoates was coupled stoichiometrically to NO3- loss, Fe2+ production, SO4(2-) loss or CH4 production, indicating that the chlorobenzoates were oxidized to CO2. To our knowledge, this is the first observation of halogenated aromatic degradation coupled to Fe reduction.

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Keywords

anaerobic microbial consortia
 
aromatic degradation
 
CH4 production
 
conditions
 
degradation
 
denitrifying conditions
 
Fe reduction
 
Fe-reducing
 
Fe2+ production
 
first observation
 
initial utilization
 
methanogenic conditions
 
monochlorobenzoate isomers
 
NO3- loss
 
River Nile sediments
 
three chlorobenzoates