TABLE 4.

Comprehensive N-glycosylation analysis of reported NA crystal structures^a

NA (PDB ID)	Asn86	Asn93	Asn146	Asn200	Asn234	Asn284	Asn307	Asn367
N1
VN04N1 (2HTY)	○	×	◆	×	○	×	×	×
18N1 (3BEQ)	○	×	◆	×	○	×	×	×
09N1 (3NSS)	◆	×	◆	×	○	×	×	×
09N1-I223R (4B7M)	◆	×	◆	×	◆	×	×	×
N2
N2 (1NN2, 2AEQ)	◆	×	◆	◆	◆	×	×	×
N2 (4GZO)	◆	×	◆	○	○	×	×	◆
N2 (4KIH)	○	×	◆	◆	○	×	×	×
N3 (4HZV)	×	×	◆	×	×	×	◆	×
N4 (2HTV)	×	×	◆	×	×	×	×	×
N5 (3SAL)	○	◆	◆	×	×	×	×	×
N6
N6 (1V0Z)	◆	×	◆	◆	×	×	×	×
N6	○	×	◆	◆	×	×	×	×
N7	○	×	◆	◆	◆	×	×	×
N8 (2HT5)	○	×	◆	×	×	×	×	×
N9 (7NN9)b	◆	×	◆	◆	×	×	×	×
Flu B (1INF, 1NSB)	×	×	○	×	×	◆	×	×

^aSymbols: ◆, a glycan is found in the crystal structure to occupy the N-glycosylation site; ○, no glycan is observed to occupy the putative N-glycosylation site in the crystal structure; ×, no N-glycosylation sequon is present in the sequence.

^bAll available N9 structures are included (PDB IDs 7NN9, 1A14, 1NMC, 2B8H, 1NCD, 4MWJ, and 4MWL).