dTDP-alpha-D-glucose + an N-acylsphing-4-enine <=> a beta-D-glucosyl-(1<->1')-N-acylsphing-4-enine + dTDP + H(+)
dtdp-alpha-d-glucose + an n-acylsphing-4-enine <=> a beta-d-glucosyl-(1<->1')-n-acylsphing-4-enine + dtdp + h(+)