a beta-D-galactosyl-(1->3)-N-acetyl-beta-D-glucosaminyl derivative + GDP-beta-L-fucose = a beta-D-galactosyl-(1->3)-[alpha-L-fucosyl-(1->4)]-N-acetyl-beta-D-glucosaminyl derivative + GDP + H(+)
a beta-d-galactosyl-(1->3)-n-acetyl-beta-d-glucosaminyl derivative + gdp-beta-l-fucose = a beta-d-galactosyl-(1->3)-[alpha-l-fucosyl-(1->4)]-n-acetyl-beta-d-glucosaminyl derivative + gdp + h(+)
"guanosine diphosphofucose-beta-acetylglucosaminylsaccharide 4-alpha-L-fucosyltransferase"
"guanosine diphosphofucose-beta-acetylglucosaminylsaccharide 4-alpha-l-fucosyltransferase"