Chlorobenzoates reductive dechlorination

Reductive dechlorination in combination with the elimination of chloride has been demonstrated in a strain of Clostridium rectum (Ohisa et al. 1982) y-hexachlorocyclohexene formed 1,2,4-trichlorobenzene and y-l,3,4,5,6-pentachlorocyclohexene formed 1,4-dichlorobenzene (Figure 7.69). It was suggested that this reductive dechlorination is coupled to the synthesis of ATP, and this possibility has been clearly demonstrated during the dehalogenation of 3-chlorobenzoate coupled to the oxidation of formate in Desulfomonile tiedjei (Mohn and Tiedje 1991). Combined reduction and elimination has also been demonstrated in methanogenic cultures that transform 1,2-dibromoethane to ethene and 1,2-dibromoethene to ethyne (Belay and Daniels 1987). 

Uotila JS, VH Kitunen, T Saastamoinen, T Coote, MM Hagblom, M Salkinoja-Salonen (1992) Characterization of aromatic dehalogenases of Mycobacterium fortuitum CG-2. J Bacteriol 174 5669-5675. van der Tweel WJJ, JB Kok, JAM de Bont (1987) Reductive dechlorination of 2,4-dichlorohenzoate to 4-chlorobenzoate and hydrolytic dehalogenation of 4-chloro-, 4-hromo-, and 4-iodohenzoate hyAcalig-enes denitrificans NTB-1. App/ Environ Microbiol 53 810-815. 

Fathepure, B. Z. Tiedje, J. M. (1994). Reductive dechlorination of tetrachloroethylene by a chlorobenzoate-enriched biofilm reactor. Environmental Science Technology, 28,746-52. 

Dolling J. and Tiedje J. M. (1987) Growth yield increase linked to reductive dechlorination in a defined 3-chlorobenzoate degrading methanogenic coculture. Arch. Microbiol. 149, 102-105. 

The reductive dechlorination of 3-chlorobenzoate by Desulfomonile tiedjei DCB-1 (Chapter 6, Section 6.6) ... 

Dolfing, J. 1990. Reductive dechlorination of 3-chlorobenzoate is coupled to ATP production and growth in an anaerobic bacterium, strain DCB-1. Arch. Microbiol. 153 264-266. 

Chlorinated benzoic acids have been shown to be intermediates in the biodegradation of several chlorinated aromatic compounds, for example, 4-chlorobenzoic acid is formed in the biodegradation of both polychlorinated biphenyls [103]. Mixed microbial cultures, which have been studied by a number of groups under aerobic conditions, can degrade a wide range of chlorinated benzoic acids, including 2-, 3- and 4-chlorobenzoic acid as well as 3,4-dichloro- and 2,4-dichlorobenzoic acid [104]. By contrast, under anaerobic conditions, only reductive dechlorination of meta-substituted benzoic acids has been observed [49,105,106]. Cometabolism of chlorobenzoic acids in the presence of unsubstituted benzoic adds leads to the formation of the corresponding... 

Sharak Genther BR, GT Townsend, BO Blattmann (1997) Reduction of 3-chlorobenzoate, 3-bromobenzoate, and benzoate to corresponding alcohols by Desulfomicrobium escambiense, isolated from a 3-chloro-benzoate-dechlorinating coculture. Appl Environ Microbiol 63 4698 703. 

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