Oxygen scavenging enzymes

Saruyama, H., and M. Tanida. 1995. Effect of chilling on activated oxygen-scavenging enzymes in low temperature-sensitive and tolerant cultivars of rice (Oryza sativa L.). Plant Sci. 109 105-113. 

Togashi, H., Shinzawa, H., Wakabayashi, H., Nakamura, T., Yamada, N., Takahashi, T. and Ishikawa, M. (1992). Activities of free oxygen radical scavenger enzymes in human liver. J. Hepatol. 11, 200-205. 

SOD is a major oxygen free radical scavenging enzyme, which may therefore have beneficial effects in liver fibrosis. Through mannosylation or coupling to the polyanion DIVEMA, SOD was made more liver specific. Both conjugates showed superior inhibition of intrahep-atic ROS production in fibrotic rats as compared to unmodified SOD. DIVEMA-SOD, however, exhibited the most potent inhibitory effects [112]. Although their mode of action is most probably extracellular free radical scavenging, Man-SOD and DIVEMA-SOD are likely to... 

Cytochrome P-450 from rat or human liver microsome preparations is inactivated when incubated anaerobically with carbon tetrachloride in the presence of NADPH and an oxygen-scavenging system (Manno et al. 1988 1992). Inactivation involved destruction of the heme tetrapyrrolic structure, and followed pseudo first-order kinetics with fast and slow half lives of 4.0 and 29.8 minutes. When compared with rat liver microsomes, the human preparations were 6-7 times faster at metabolizing carbon tetrachloride, and only about one- eighth as susceptible to suicide inactivation (about 1 enzyme molecule lost for every 196 carbon tetrachloride molecules metabolized). 

Karabulut AK, Ulger H, Pratten MK. Protection by free oxygen radical scavenging enzymes against salicylate-induced embryonic malformations in vitro. Toxicol In Vitro 2000 14(4) 297-307. 

Kazura, J. W. and Meshnick, S. R. (1984) Scavenger enzymes and resistance to oxygen mediated damage in Trichinella spiralis. Mol. Biochem. Parasitol. 10 1-10. 

Factors scavenging reactive oxygen species Enzymes. Two types of enzymes exist to remove H2O2 within cells (Fig. 2) the haem protein CAT, present in most aerobic cells, which catalyses the degradation of H2O2 to triplet O2 and water (Eq. 

The active-oxygen scavenging system in plants consists of five enzymes si )eroxide dismutase (SOD), glntathlcaie reductase, dehydroascorbate reductase, monod ydroascorbate reductase, and ascorbate peroxidase (reviewed in 8). 

Table HI. Effect of ( )-Epigallocatechin 3-0-Gallate on the Activities of Reactive Oxygen Species-Scavenging Enzymes in Rats after Nephrectomy...

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