Table 2.

Initiating transferase sugar specificities.

Itr name	First sugar	References
ItrA1	D-QuipNAc4NRa	42,43
ItrA2	D-GalpNAc	8,43–45
ItrA3	D-GlcpNAc	43,46
ItrA4	D-Galp	22
ItrB1	D-QuipNAc	47
ItrB2	–b	–
ItrB3	D-FucpNAc	48

^aR is either Acetyl (Ac) or (S)-3-hydroxybutanoyl.

^bItrB2 is redundant.