Publications by authors named "W M Owais"

The mutagenic and toxic activities of sodium azide (NaN(3) ) and its organic metabolite L-azidoalanine [N(3)-CH(2)-CH(NH)(2)-COOH] were examined in the different stages of spermatogenesis in Drosophila melanogaster. Both azide and azidoalanine were toxic to the injected males, but azidoalanine was significantly less toxic than sodium azide. Following the injection with 0.

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The Bacillus subtilis ATCC 6633 strain synthesizes a mutagenic metabolite from sodium azide and O-acetylserine. Mutagenicity of azide was decreased in growth media containing 10(-4) M glutathione, L-cysteine or L-djenkolic acid whereas dithiothritol (DTT) added at the same concentration did not reduce the mutagenicity of azide. Likewise, glutathione, L-cysteine, L-djenkolic acid, and DTT were found to have no effect in reducing the mutagenicity of the in vitro produced metabolite using bacterial cell-free extract.

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Glutathione S-transferase activity toward 1-chloro-2,4-dinitrobenzene was detected in various developmental stages of Drosophila melanogaster. The specific activity of the enzyme was 110, 35, 25 and 15 nmol/min/mg protein in crude extracts prepared from eggs, larvae, pupae and adult stages respectively. The enzymes from larval, pupal and adult stages were purified and compared.

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A Bacillus subtilis transformation system was used to investigate the possible direct effect of L-azidoalanine on DNA in vitro. A B. subtilis (trp-) deletion and repair deficient (uvr-) strain was constructed and used as a recipient for treated DNA.

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The gene coding for O-acetylserine sulfhydrylase (OASS) from E. coli K12 was cloned into the vector pBR322 plasmid and expressed in a cysk mutant strain of E. coli that is deficient in O-acetylserine sulfhydrylase (OASS-).

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