Toluene, metabolism

Human polymorphisms in several enzymes involved in toluene metabolism are known. In Mongoloid populations, deficiency in the low form of aldehyde dehydrogenase H2 (ALDH2) is common approximately half of the Japanese population lacks this enzyme. In ALDH2-deficient exposed workers, an increased level of benzyl alcohol was found, but benzaldehyde was not detectable urinary excretion of hippurate was decreased in the deficient individuals. The CYPlAl polymorphism, alcohol consumption and smoking were all associated with decreased hippurate excretion, but the interdependence was too complex to allow detailed conclusions on the mechanisms to be drawn (Kawamoto et al., 1995). 

Kawamoto, T., Koga, M., Murata, K., Matsuda, S. Kodama, Y. (1995) Effects of ALDH2, CYPlAl, and CYP2E1 genetic polymorphisms and smoking and drinking habits on toluene metabolism in humans. Toxicol, appl. Pharmacol., 133, 295-304... 

Nakajima, T.. Wang, R.-S., Elovaara, E., Park, S.S., Gelboin, H.V., Hietanen. E. Vainio, H. (1991) Monoclonal antibody-directed characterization of cytochrome P450 isozymes responsible for toluene metabolism in rat liver. Biochem. Pharmacol., 41, 395-404... 

Smith-Kielland, A. Ripel, A. (1993) Toluene metabolism in isolated rat hepacytes effects of in... 

Whether toluene metabolism was coupled to nitrate reduction was determined in several ways. Activity on toluene by the enrichment culture could be transferred and sustained in the transferred cultures. As shown in Table III, active enrichment cultures were provided with substrate toluene, with nitrate or with both. In the absence of the electron-acceptor nitrate with... 

Coschigano, P.W., T.S. Wehrman, and L.Y. Young. 1998. Identification and analysis of genes involved in anaerobic toluene metabolism by strain Tl putative role of a glycine free radical. Appl. Environ. Microbiol. 64 1650-1656. 

D. Kinetics. Toluene is metabolized by alcohol dehydrogenase, and the presence of ethanol can inhibit toluene metabolism and prolong systemic toxicity. 

Ling KH, Hanzlik RP. Deuterium isotope effects on toluene metabolism. Product release as a rate-limiting step in cytochrome P-450 catalysis. Biochem Biophys Res Commun 1989 160 844-849. 

Yuan W, Sequeira DJ, Cawley GE, Eyer CS, Backes WL (1997) Time course for the modulation of hepatic cytochrome P450 after administration of ethylbenzene and its correlation with toluene metabolism. Arch Biochem Biophys 339 55-63... 

Leuthner B, Leutwein C, Schulz H, Horth P, Haehnel W, SchiltzE, Schafer H, Heider J (1998) Biochemical and genetic characterization of benzylsuccinate synthase from Thauera aromatica a new glycyl radical enzyme catalysing the first step in anaerobic toluene metabolism. Mol Microbiol 28 615-628... 

Wright, A., andR. H. Olsen. 1994. Self-mobilization and organization of the genes encoding the toluene metabolic pathway of Pseudomonas mendocina KRl. Appl. Environ. Microbiol. 60 235-241. 

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