FORMATE: The next big thing in one-carbon metabolism?

Formate, originally discovered in ant stings, is nowadays more often thought of in terms of chemistry and industry than of biology. In preliminary metabolomis experiments, using ¹H-NMR, we have found that serum formate levels are markedly elevated in Vitamin B₁₂ deficiency. We confirmed this finding with our newly-developed formate assay and extended these observations to folate deficiency, in which situation formate is also elevated. We can understand these findings in terms of the known pathways in one-carbon metabolism. We have measured the endogenous rate of formate production in folate-deficient rats and have shown that this molecule is a significant, though unrecognised, end-product of amino acid metabolism. We are currently measuring plasma formate in large human cohorts (500 from Oxford and 2500 from Dublin) so as to determine the utility of this molecule as a biomarker for detecting nutritional and/or genotypic differences in free-living human populations.