Metabolism of vertebrate amino sugars with N-glycolyl groups: elucidating the intracellular fate of the non-human sialic acid N-glycolylneuraminic acid.

ABSTRACT: The two major mammalian sialic acids are N-acetylneuraminic acid and N-glycolylneuraminic acid (Neu5Gc). The only known biosynthetic pathway generating Neu5Gc is the conversion of CMP-N-acetylneuraminic acid into CMP-Neu5Gc, which is catalyzed by the CMP-Neu5Ac hydroxylase enzyme. Given the irreversible nature of this reaction, there must be pathways for elimination or degradation of Neu5Gc, which would allow animal cells to adjust Neu5Gc levels to their needs. Although humans are incapable of synthesizing Neu5Gc due to an inactivated CMAH gene, exogenous Neu5Gc from dietary sources can be metabolically incorporated into tissues in the face of an anti-Neu5Gc antibody response. However, the metabolic turnover of Neu5Gc, which apparently prevents human cells from continued accumulation of th

SUBMITTER: Bergfeld AK 

PROVIDER: S-EPMC3436522 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature