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