alpha-D-glucose 1-phosphate + GDP + H(+) => GDP-alpha-D-glucose + phosphate
alpha-d-glucose 1-phosphate + gdp + h(+) => gdp-alpha-d-glucose + phosphate
alpha-D-glucose 1-phosphate + GDP + H(+) => GDP-alpha-D-glucose + phosphate
alpha-d-glucose 1-phosphate + gdp + h(+) => gdp-alpha-d-glucose + phosphate