N-acetyl-alpha-D-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + GDP-alpha-D-mannose <=> alpha-D-mannosyl-(1->3)-N-acetyl-alpha-D-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + GDP + H(+)
n-acetyl-alpha-d-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + gdp-alpha-d-mannose <=> alpha-d-mannosyl-(1->3)-n-acetyl-alpha-d-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + gdp + h(+)
N-acetyl-alpha-D-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + GDP-alpha-D-mannose <=> alpha-D-mannosyl-(1->3)-N-acetyl-alpha-D-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + GDP + H(+)
n-acetyl-alpha-d-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + gdp-alpha-d-mannose <=> alpha-d-mannosyl-(1->3)-n-acetyl-alpha-d-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + gdp + h(+)