Biosynthesis of L-ascorbic acid in plants: new pathways for an old antioxidant.
The biosynthetic pathway of L-ascorbic acid (vitamin C) in plants has been established for several years. However, recent reports describe alternative pathways, revealing a more complex picture of L-ascorbic acid biosynthesis than had been expected. GDP-L-gulose and myo-inositol are proposed as new intermediates in L-ascorbic acid biosynthesis, indicating that part of the animal pathway might also be operating in plants. Enzymatic studies on the GDP-mannose- 3',5'-epimerase and L-galactono-1,4-lactone dehydrogenase suggest that they are important regulatory steps for L-ascorbic acid biosynthesis.
Valpuesta
Victoriano
V
Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga, Spain. valpuesta@uma.es
Botella
Miguel A
MA
D001205:Ascorbic Acid / Q000096:biosynthesis* / Q000737:chemistry; D018506:Gene Expression Regulation, Plant; D008956:Models, Chemical; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010944:Plants / Q000378:metabolism*
D001205:Ascorbic Acid