TABLE 3.

H-bond interactions between mAbs S55-3 and S55-5 to lipid A analogue BBP-NAc

Numbering scheme given in Table 2. The distance cutoff for hydrogen bond assignment was 3.3 Å, except for charged residue interactions where the distance cutoff was 3.9 Å. Hydrogen bond distances shown for S55-3 is averaged over the three molecules in the asymmetric unit.

Antigen		Residue		CDR	Distance (Å)
Residue	Atom(s)	Residue	Atom		S55-3	S55-5
GlcN4P	4PO4	Arg(L)-96	NH1	L3	2.94a	2.96a
		Arg(L)-96	NH2	L3	3.08a	3.00a
		His(H)-95	ND1	H3	3.00a	2.88a
		AsnH100C	N	H3	2.83	2.75
		AsnH100C	ND2	H3	2.97	2.92
GlcN1P	1PO4	Ser(H)-52	OG	H2	2.69	3.06
		Gly(H)-53	N	H2	3.17	2.80
		Ser(H)-55	N	H2	3.09	2.93
		Ser(H)-55	OG	H2	2.69	2.49

^a Charged residue interaction is shown. Protonation of the His residues is assumed as both proteins were crystallized below pH 5.0.