Alanine metabolism

The single step synthesis of alanine from pyruvate is unique to Coccidians such as Toxoplasma and Neospora among the phylum of Apicomplexa. This is absent in other groups such as Plasmodium, Theileria and Cryptosporidium species, which utilise alanine from host [1]. Alanine dehydrogenase and alanine transaminase are the enzymes which catalyse this one step conversion. Alanine racemase, a pyridoxal phosphate dependent enzyme which catalyses isomerisation of L-alanine to D-alanine is present in Plasmodium falciparum, Neospora caninum and Toxoplasma gondii genomes and annotated to pyridoxal phosphate metabolism pathway in MPMP as an example of enzyme which requires pyridoxal phosphate as cofactor for its function. The only difference between T. gondii and N. caninum in this pathway is the copy number variation of alanine dehydrogenase enzyme (2 in T. gondii and 3 in N. caninum).

List of genes annotated as tRNA-Ala in N. Caninum genome

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Sources and fates of metabolites