Table 2.

Carbohydrate-Ab hydrogen bonding interactions

Sugar atom	Residue	Atom	Distance, Å
Upstream terminal perosamine
O3	Asp H33	Oδ2	2.68
O3	His H95	Nδ1	2.55
O1′	Ala H98	N	2.78
O2′	Asp H33	N	2.88
O2′	His H95	O	2.74
O4′*	Thr H31	O	2.90
Second perosamine residue
O3	Trp L91	Nɛ1	2.85

^*This interaction is observed only in the structure of the Fab-monosaccharide complex.