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Figure 2: Smirnoff-Wheeler Pathway

GDP-L-galactose by GDP-mannose- 3′,5′-epimerase (Wolucka et al., 2001) which is then
converted to L-galactose. L-Galactono-1, 4-lactone is formed by the oxidation of L-galactose

by the NAD-dependent L-galactose dehydrogenase. L-Galactono-1,4-lactone here acts as the

immediate precursor of L-ascorbic acid and is oxidized to L-ascorbic acid by L-galactono-
1,4-lactone dehydrogenase, it is present on the outer side of the inner membrane of

mitochondria (Bartoli et al., 2000; Siendones et al., 1999). Although the initial steps of the

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