Adenosine-to-inosine editing in the anticodon of tRNAs is essential for viability. Enzymes mediating tRNA adenosine deamination in bacteria and yeast contain cytidine deaminase-conserved motifs, suggesting an evolutionary link between the two reactions. In trypanosomatids, tRNAs undergo both cytidine-to-uridine and adenosine-to-inosine editing, but the relationship between the two reactions is ...

Cordycepin, which is an analogue of a nucleoside adenosine, exhibits a wide variety of pharmacological activities including anticancer effects. In this study, ADA1- and ADA2-expressing HEK293 cells were established to determine the major ADA isoform responsible for the deamination of cordycepin. While the metabolic rate of cordycepin deamination was similar between ADA2-expressing and Mock cell...

The oxidative and conjugative metabolism of sertraline was examined in vitro to identify the enzymes involved in the generation of N-desmethyl, deaminated, and N-carbamoyl-glucuronidated metabolites in humans. In human liver microsomes, sertraline was N-demethylated and deaminated by cytochrome P450 (P450) enzymes with overall K(m) values of 98 and 114 microM, respectively, but the intrinsic cl...

Deamination of nucleobases in DNA and RNA results in the formation of xanthine (X), hypoxanthine (I), oxanine, and uracil, all of which are miscoding and mutagenic in DNA and can interfere with RNA editing and function. Among many forms of nucleic acid damage, deamination arises from several unrelated mechanisms, including hydrolysis, nitrosative chemistry, and deaminase enzymes. Here we presen...

Cytosine deaminase (CDA) from E. coli is a member of the amidohydrolase superfamily. The structure of the zinc-activated enzyme was determined in the presence of phosphonocytosine, a mimic of the tetrahedral reaction intermediate. This compound inhibits the deamination of cytosine with a K(i) of 52 nM. The zinc- and iron-containing enzymes were characterized to determine the effect of the dival...