a lactoside III(4)-a-Fuc-Lc4Cer + GDP-beta-L-fucose = a lactoside IV(2),III(4)-a-[Fuc]2-Lc4Cer + GDP + H(+)
a lactoside iii(4)-a-fuc-lc4cer + gdp-beta-l-fucose = a lactoside iv(2),iii(4)-a-[fuc]2-lc4cer + gdp + h(+)
a lactoside III(4)-a-Fuc-Lc4Cer + GDP-beta-L-fucose = a lactoside IV(2),III(4)-a-[Fuc]2-Lc4Cer + GDP + H(+)
a lactoside iii(4)-a-fuc-lc4cer + gdp-beta-l-fucose = a lactoside iv(2),iii(4)-a-[fuc]2-lc4cer + gdp + h(+)