(2R)-2-O-(alpha-D-glucopyranosyl)-glycerate + GDP + H(+) => GDP-alpha-D-glucose + (R)-glycerate
(2r)-2-o-(alpha-d-glucopyranosyl)-glycerate + gdp + h(+) => gdp-alpha-d-glucose + (r)-glycerate
(2R)-2-O-(alpha-D-glucopyranosyl)-glycerate + GDP + H(+) => GDP-alpha-D-glucose + (R)-glycerate
(2r)-2-o-(alpha-d-glucopyranosyl)-glycerate + gdp + h(+) => gdp-alpha-d-glucose + (r)-glycerate