Characterization of Two Arabidopsis L-Gulono-1,4-lactone Oxidases, AtGulLO3 and AtGulLO5, Involved in Ascorbate Biosynthesis.

ABSTRACT: L-Ascorbic acid (AsA, vitamin C) is an essential antioxidant for plants and animals. There are four known ascorbate biosynthetic pathways in plants: the L-galactose, L-gulose, D-galacturonate, and myo-inositol routes. These pathways converge into two AsA precursors: L-galactono-1,4-lactone and L-gulono-1,4-lactone (L-GulL). This work focuses on the study of L-gulono-1,4-lactone oxidase (GulLO), the enzyme that works at the intersect of the gulose and inositol pathways. Previous studies have shown that feeding L-gulono-1,4-lactone to multiple plants leads to increased AsA. There are also reports showing GulLO activity in plants. We describe the first detailed characterization of a plant enzyme specific to oxidize L-GulL to AsA. We successfully purified a recombinant Arabidopsis

SUBMITTER: Aboobucker SI 

PROVIDER: S-EPMC6088757 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature