Detoxification arsenic

Yang H-C, J Cheng, TM Finan, BP Rosen, H Bhattacharjee (2005) Novel pathway for arsenic detoxification in the legume symbiont Sinorhizobium meliloti. J Bacterial 187 6991-6997. 

Crameri, A., S.A.Raillard, E.Bermudez and W.P.Stenuner. (1998) Molecular evolution of an arsenate detoxification pathway by DNA shuffling. Nature, 391, 288-291. 

FIGURE 72.2. Arsenic detoxification mechanisms (reduction, oxidation, methylation, and resistance) in prokaryotes. (A) Respiratory arsenate reductase (Arr) is involved in the reduction of As(V) by the dissimilatory arsenate respiring organisms. (B) Arsenite oxidase (Aox/Aso) is responsible for oxidation of As(III) by chemoautotrophic or heterotrophic arsenite oxidizers. 

Once inside the cell, there is a problem involving arsenate detoxification due to the structural similarity with... 

Martin, P., DeMel, S., Shi, J., Gladysheva, T., Gatti, D.L., Rosen, B.P., Edwards, B.F.P. (2001). Insights into the structure, solvation, and mechanism of ArsC arsenate reductase, a novel arsenic detoxification enzyme. Structure 9 1071-81. 

Arsenic detoxification and evolution of trimethylarsine gas by a microbial arsenite S-adenosylmethionine methyl-transferase. Proc. Natl Acad. Sci. USA 103 2075-80. 

Rosen, B.P. (2002a). Biochemistry of arsenic detoxification. FEBS Lett. 529 86-92. 

Rosen B. P. (2002) Biochemistry of arsenic detoxification. Febs Lett. 529, 86-92. 

Rosen, B. P. (2002). Biochemistry of arsenic detoxification. FEBS Lett. 529, 86-92. Sadiq, M. (1997). Arsenic chemistry in soils an overview of thermodynamic predictions... 

Arsenate detoxification pathway Arsenic resistance 12-fold increased rate of arsenate reduction DNA shuffling + selection E. coli [200]... 

C Diorio, J Cai, J Marmor, R Shinder, MS DuBow. An Escherichia coli chromosomal ars operon homolog is functional in arsenic detoxification and is conserved in gram-negative bacteria. J Bacteriol 177 2050-2056, 1995. 

Both oxidation and methylation are microbial transformations involved in the redistribution and global cycling of arsenic. Oxidation involves the conversion of toxic arsenite to less toxic arsenate. Bacterial methylation of inorganic arsenic under anaerobic conditions may be a mechanism of arsenic detoxification. Fungi also transform inorganic and organic arsenic compounds into volatile methylar-sines. However, unlike methylated selenium which is nontoxic, the volatile arsine... 

Cox M, Gerritse G, Dankmeyer L, Quax WJ (2001) Characterization of the promoter and upstream activating sequence from the Pseudomonas alcaligenes lipase gene. J Biotechnol 86 9-17 Crameri A, Dawes G, Rodriguez E Jr, Silver S, Stemmer WP (1997) Molecular evolution of an arsenate detoxification pathway by DNA shuflfling. Nat Biotechnol 15 436-438... 

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