label: alpha-D-mannosyl-(1->3)-N-acetyl-alpha-D-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + 2 GDP-alpha-D-mannose = alpha-D-mannosyl-(1->3)-alpha-D-mannosyl-(1->3)-alpha-D-mannosyl-(1->3)-N-acetyl-alpha-D-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + 2 GDP + 2 H(+)
label_lc: alpha-d-mannosyl-(1->3)-n-acetyl-alpha-d-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + 2 gdp-alpha-d-mannose = alpha-d-mannosyl-(1->3)-alpha-d-mannosyl-(1->3)-alpha-d-mannosyl-(1->3)-n-acetyl-alpha-d-glucosaminyl-di-trans,octa-cis-undecaprenyl diphosphate + 2 gdp + 2 h(+)