In vitro characterization of alternative l-threonate and d-erythronate catabolic pathways
l -threonate is the metabolite of vitamin C, while d -erythronate is the metabolite of N -acetyl- d -glucosamine, the nutritional supplement for joint health. They are widely distributed in the environment and human biofluids. Nevertheless, the catabolisms of l -threonate and d -erythronate are sparsely reported. Here we explored the functional diversity of an acid sugar kinase family (Pfam families PF07005-PF17042), and discovered a novel 2-oxo-tetronate kinase. The conserved genome neighborhood of the 2-oxo-tetronate kinase encodes members of class-II fructose-bisphosphate aldolase family (F_bP_aldolase, PF01116) and a dehydrogenase family (PF03446-PF14833). Instructed by this analysis, we experimentally verified that these enzymes are capable of degrading l -threonate into dihydroxyacetone phosphate (DHAP) in Arthrobacter sp. ZBG10, Clostridium scindens ATCC 35704, and Pseudonocardia dioxanivorans ATCC 55486. Meanwhile, a convergent catabolic pathway for d -erythronate was characterized in P . dioxanivorans ATCC 55486. Moreover, the phylogenetic distribution analysis indicates that the biological range of the identified l -threonate and d -erythronate catabolic pathways appears to extend mostly to members of the Actinomycetota , Cyanobacteriota , Bacillota , Pseudomonadota , and Bacteroidota phyla.
危险品化学品经营许可证（带存储）