Mechanism of bacterial degradation

Haggblom M (1990) Mechanisms of bacterial degradation and transformation of chlorinated monoaromatic compounds. J Basic Microbiol 30 115-141. 

Kawai F (1992), Mechanisms of Bacterial degradation of polyethers and their copolymers , in Vert M, Biodegradable Polymers and Plastics, Cambridge, The Royal Society of Chemistry, 20-29. 

Different mechanisms to explain the disinfection ability of photocatalysts have been proposed [136]. One of the first studies of Escherichia coli inactivation by photocatalytic Ti02 action suggested the lipid peroxidation reaction as the mechanism of bacterial death [137]. A recent study indicated that both degradation of formaldehyde and inactivation of E. coli depended on the amount of reactive oxygen species formed under irradiation [138]. The action with which viruses and bacteria are inactivated by Ti02 photocatalysts seems to involve various species, namely free hydroxyl radicals in the bulk solution for the former and free and surface-bound hydroxyl radicals and other oxygen reactive species for the latter [139]. Different factors were taken into account in a study of E. coli inactivation in addition to the presence of the photocatalyst treatment with H202, which enhanced the inactivation... 

Intrinsic resistance to biocides as a consequence of bacterial degradative activities is thus not a major mechanism of insusceptibility. There are, of course, examples of plasmid-mediated enzymes that confer resistance to inorganic (and sometimes organic) mercurials and these will be discussed later... 

Information on the hydrolytic activity in marine sediments has been obtained from the use of model substrates labeled with fluorescent dyes such as methylumbelliferone (MUF) or fluorescein. These substrates may be small dimeric molecules, the hydrolytic cleavage of which releases the fluorescence signal, which is then indicative of the activity of specific enzymes such as glucosidase, chitobiase, lipase, ami-nopeptidase or esterase (Chrost 1991). Also large fluorescently labeled polymers such as the polysaccharides laminarin or pullulan have been used in experiments to demonstrate the mechanism and kinetics of bacterial degradation (Amosti 1996). 

Lefebvre-Drouet E, Rousseau MF (1995) Dissolution de difierents oxyhydroydes de fer par vole chimique et par voie biologique importance des bacteries reductrices. Soil Biol Biochem 27 1041—1050 Lemaire J, Dabin P, Arnaud R (1992) Mechanisms of abiotic degradation of synthetic polymers. In Vert M, Feijen J, Albertsson A, Scott G, Chiellini E (eds) Biodegradable polymers and plastics. Ro) Society of Chemistry, Cambridge, pp 30-39... 

Kiwi,). and Nadtochenko, V. (2005) Evidence for the mechanism of photocatalytic degradation of the bacterial wall membrane at the Ti02 interface by ATR-FTIR and laser kinetic spectroscopy. Langmuir, 21, 4631-41. 

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