A member of the nucleic acid/nucleotide deaminase superfamily prototyped by Orientia OTT_1508 [1]. Members of this family are present in a wide phyletic range of bacteria,including several intracellular parasites and eukaryotes such as fungi, Leishmania, Selaginella, and some apicomplexa. In bacteria, these deaminases are predicted to function as toxins in bacterial polymorphic toxin systems [1]. Versions in intracellular bacteria lack immunity proteins and are likely to be deployed against their eukaryotic hosts. Eukaryotic versions are predicted to function as nucleic acid (either DNA or RNA) deaminases. Among eukaryotes, some fungi show lineage-specific expansions of this family. Many fungal versions are fused to a distinct N-terminal globular domain. Various fungal versions are fused to domains involved in chromatin function. Apicomplexan versions are fused to tRNA guanine transglycosylase domain [1].

1: Evolution of the deaminase fold and multiple origins of eukaryotic editing and mutagenic nucleic acid deaminases from bacterial toxin systems. Iyer LM, Zhang D, Rogozin IB, Aravind L; Nucleic Acids Res. 2011; [Epub ahead of print] PMID:21890906