Oxidative damage responses

Several stress responses to exposure to environmental contaminants have been studied and are exemplified by the SOS response (Quillardet et al., 1989 Sassanfar et al., 1990 Kenyon et al., 1998), the heat-shock response (Demple and Harrison, 1994 Lee et al., 2003), and the oxidative damage response (Hidalgo et al., 1994 Asad et al.,... 

E. coli, like all organisms, has the ability to adjust to varying environmental situations and toxicity. When the bacterium experiences an environmental stress, a signal transduction cascade occurs in which certain promoters are induced and their proteins are expressed. Some of the more elucidated responses include the SOS response(24), which is concerned with damage to the cellular DNA, the oxidative-damage response and the response to protein damage. 

Wang J, Schramm D and Holt R. 2000. A dose-response effect from chocolate consumption on plasma epicatechin and oxidative damage. J Nutr 130 2115S-2119S. 

General descriptors may be related to the metabolism responses in the biofilm. Biofilm algae have several mechanisms to counterbalance the damage caused by the toxicants. Environmental stress produces oxidative damage in the cells, which can be tracked down by means of the analysis of many enzymes (superoxide dismutase, catalase, peroxidase, etc.) that function as effective quenchers of reactive oxygen species (ROS). 

The inflammatory response changes with time and can be divided into phases. The rapid phase occurs within seconds to minutes and consists of vasodilation, increased blood flow, edema, and pain. The acute phase is characterized by induction of inflammatory genes by NF-kB and other transcription factors. During this phase, moderate amounts of inflammatory mediators are produced. The chronic phase occurs over months to years and is marked by dramatically increased production of inflammatory mediators. The secondary chronic phase of inflammation occurs after years of oxidative damage has degraded blood vessels and tissues. Such chronic inflammation appears to play a role in many disease states, such as arteriosclerosis and cancer. 

Wang, J.F., Schramm, D.D., Holt, R.R., Ensunsa, J.L., Fraga, C.G., Schmitz, H.H., and Keen, C.L., A dose-response effect from chocolate consumption on plasma epicatechin and oxidative damage, J. Nutr., 130, 2115S, 2000. 

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