Pseudomonas putida toluene degradation

Zylstra GJ, LP Wackett, DT Gibson (1989) Trichloroethylene degradation by Escherichia coli containing the cloned Pseudomonas putida FI toluene dioxygenase genes. Appl Environ Microbiol 55 3162-3166. 

The degradation of toluene has been studied extensively in strains of Pseudomonas putida, and details of the three different pathways have been resolved. 

Althongh the prodnct from the transformation of toluene by mntants of Pseudomonas putida lacking dehydrogenase activity is the cis-2R,3S dihydrodiol, the cis-2S,3R dihydrodiol has been synthesized from 4-iodotoluene by a combination of microbiological and chemical reactions. P. putida strain UV4 was used to prepare both enantiomers of the di-dihydrodiol, and iodine was chemically removed nsing H2 -Pd/C. Incubation of the mixtnre of enantiomers with P. putida NCIMB 8859 selectively degraded the 2R,3S componnd to prodnce toluene cis-2S,3R dihydrodiol (Allen et al. 1995). 

Zylstra GJ, DT Gibson (1989) Toluene degradation by Pseudomonas putida FI. Nucleotide sequence of the todClClBADE genes and their expression in Escherichia coli.J Biol Chem 264 14940-14946. 

The enzymes of alternative pathways may be induced in a given strain by growth with different substrates for example, growth of Pseudomonas putida R1 with salicylate induces enzymes of the extradiol fission pathway, whereas growth with benzoate induces those of the intradiol pathway (Chakrabarty 1972). As a broad generalization, the extradiol fission is preferred for the degradation of more complex compounds such as toluene, naphthalene, and biphenyl (Furukawa et al. 1983). 

Biological. Under anaerobic conditions using a sewage inoculum, 3-nitrotoluene and 4-nitrotoluene both degraded to toluidine (Hallas and Alexander, 1983). Robertson et al. (1992) reported that toluene dioxygenases from Pseudomonas putida FI and Pseudomonas sp. Strain JS 150 oxidized the methyl group forming 3-nitrobenzyl alcohol. 

Zylstra, G. J.,Chauhan,S. Gibson, D. T. (1990). Degradation of chlorinated biphenyls by Escherichia coli containing cloned genes of the Pseudomonas putida FI toluene catabolic pathways. In Proceedings of the 16th Annual Hazardous Waste Research Symposium Remedial Action, Treatment, and Disposal of Hazardous Waste, pp. 290-302. EPA/600/9-90/037. Cincinnati, OH U.S. Environmental Protection Agency. 

Wackett, L. P. Gibson, D. T. (1988). Degradation of trichloroethylene by toluene dioxygenase in whole cell studies with Pseudomonas putida FI. Applied and Environmental Microbiology, 54, 1703-8. 

Pseudomonas putida FI (which contains a chromosomally encoded tod operon for toluene degradation) was genetically modified by the introduction of tod-lux CDABE into the chromosome yielding the biosensor Pseudomonas putida TVA8 (Applegate et al., 1998). The tod operon is induced when exposed to several compounds such as benzene, toluene, ethylbenzene and xylene (Shingleton et al., 1998). 

Cho, M.C., Kang, D-O., Yoon, B.D., and Lee K., Toluene degradation pathway from Pseudomonas putida FI substrate specificity and gene induction by 1-substituted benzenes, J. Ind. Microbiol. Biotechnol., 25, 163-170, 2000. 

Wang, Y., Rawlings, M., and Gibson, D.T., Identification of a membrane- protein and a truncated lysr-type regulator associated with the toluene degradation pathway in Pseudomonas putida FI, Molecular and Gen. Genet., 246, 570-579, 1995. 

Trichloroethene and aromatic compounds — A striking example is the degradation of trichloroethene by different strains of Pseudomonas sp. grown with phenol (Folsom et al. 1990) or with toluene. This capability has already been noted in Section 4.4.1.1 in the context of monooxygenase reactions, and has attracted attention for the bioremediation of contaminated sites (Hopkins and McCarty 1995). Conversely, toluene degradation is induced (a) by trichloroethene in a strain of P. putida (Heald and Jenkins 1994) and (b) in P. mendocina — although not in Burkholderia (Pseudomonas) cepacia or P. putida strain FI — by trichloroethene, pentane, and... 

Whereas degradation of the readily extractable toluene in spiked soil by Pseudomonas putida was rapidly accomplished, there was a residue that was degraded much more slowly at a rate that was apparently dependent on its desorption (Robinson et al. 1990). 

However, several bacterial strains, capable of degrading toluene and to oxidize nitrobenzene, have been isolated. While in cells of Pseudomonas putida FI and Pseudomonas sp. strain JS150, a dioxygenase medianism converts nitrobenzene into the corresponding dihydrodiol, in other microorganisms, a monoo genase is instead responsible for the initial attack on nitrobenzene [55]. 

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