TABLE 2.

Class-specific residues that distinguish different known and suggested antigenic norovirus strains belonging to different evolutionary classes for partitions P01 to P07 of the phylogenetic tree constructed from a subset (S1 to S56) of sequences of Fig. 1^a

Partitions (from Fig. 1)	Evolutionary class		Sequence clusters in class	Antigenic norovirus strains in class	Class-specific residues and insertions that occur in the different evolutionary classes corresponding to the first few partitions
	Total	ID
P01	1		S1-S56	DSV, SOV, NV, MXV, HV, SMV, LSV
P02, P03, P04	2	GI	S1-S10	DSV, SOV, NV	44A, 70I, 104V, 106N, 163E, 201V, 203A, 204G, 226Q, 329H, 375W, 377S, 397S, 414F, 434P, 460H, 463D, 471G, 485P*, 486N*, 500V, 514K, 519A, 527G*
		GII	S12-S56	MXV, HV, SMV, LSV	44P, 70V, 104A, 106G, 163P, 201T, 203S, 204C, 226S, 329G, 375P, 377G, 397G, 414P, 434D, 460R, 463N, 471F, 500Y, 514A, 519G
P05	3	GIa	S1-S10	DSV, SOV, NV	GI + [83L, 181R, 227K, 306G, 492P]
		GIIa	S12-S42	MXV, HV, SMV	GII + [83L, 181R, 227K, 306G, 492P]
		GIIb	S43-S56	LSV	GII + [83A, 181K, 227R, 306W, 492D]
P06	7	GIb	S1-S3	DSV	GIa + [46A, 229K, 232S, 236L, 241L]
		GIc	S4-S6	SOV	GIb: [199S, 229R, 232T, 236I, 310M]
		GId	S7-S9	NV	GIb: [84S, 197G*, 229R, 232T, 241L,]
		GIIc	S12-S23	MXV	GIIa + [46T, 195G*, 199V, 229K, 232T]
		GIId	S25-S37	HV, SMV	GIIa: [65N, 241L, 509Q]
		GIIe	S39-S42	HV, SMV	GIIa: [46V, 250V, 509Q]
		GIIf	S43-S56	LSV	GIIa: [46A, 250L, 275V, 306W, 310D]
P07	8	GIb	S1-S3	DSV	P06+ 43A, 65Q, 82D, 125I, 133A, 142A, 149I, 156E, 160V, 203C, 223N, 239N, 240T, 246V, 253M, 259H, 288C, 301L, 347*, 356L, 389P, 401E, 422M, 446V, 452T, 504V
		GIe	S4-S5	DSV	P06+ 43L, 65Q, 82D, 125I, 133Q, 142A, 149I, 156D, 160V, 203C, 223T, 239K, 240Y, 246I, 253M, 259Q, 288C, 301L, 347P, 356L, 389F, 401E, 422M, 446I, 452I, 504A
		GId	S7-S9	NV	P06+ 43V, 65Q, 82D, 125V, 133G, 142A, 149I, 156D, 160V, 203C, 223T, 239S, 240S, 246A, 253M, 259N, 288A, 301L, 347T, 356L, 389L, 401E, 422M, 446A, 452T, 504V
		GIIc	S12-S23	MXV	P06+ 43A, 65G, 82N, 125F, 133P, 142I, 149I, 156E, 160L, 203R, 223T, 239S, 240E, 246F, 253L, 259E, 288C, 301L, 347T, 356L, 389Q, 401H, 422R, 446Y, 452A, 504E
		GIIg	S25-S32	HV	P06+ 43A, 65N, 82N, 125F, 133P, 142I, 149I, 156E, 160L, 203R, 223T, 239G, 240E, 246F, 253L, 259E, 288C, 301V, 347T, 356L, 389Q, 401L, 422R, 446Y, 452S, 504D
		GIIh	S33-S37	SMV	P06+ 43A, 65N, 82N, 125F, 133P, 142I, 149I, 156E, 160L, 203R, 223T, 239G, 240E, 246F, 253M, 259E, 288C, 301I, 347T, 356L, 389Q, 401L, 422R, 446Y, 452S, 504D
		GIIi	S39-S41	SMV	P06+ 43A, 65A, 82D, 125F, 133P, 142L, 149V, 156E, 160L, 203R, 223S, 239S, 240E, 246F, 253M, 259E, 288C, 301L, 347T, 356I, 389Q, 401N, 422R, 446Y, 452A, 504E
		GIIf	S43-S56	LV	P06+ 43A, 65G, 82S, 125F, 133P, 142V, 149I, 156E, 160I, 203R, 223T, 239E, 240E, 246F, 253L, 259S, 288C, 301L, 347T, 356L, 389Q, 401R, 422R, 446Y, 452A, 504D

^aOnly seven partitions P01 to P07 are shown because these are sufficient to clearly demonstrate all the relevant ET features discussed in the text. The remaining partitions can be viewed as supplementary data (http:/ncmi.bcm.tmc.edu/∼chin). Although class-specific residues are shown beginning at residue 1 in Fig. 2, only residues in locations 44 and higher are shown here because of the lack of knowledge of some of the N-terminal residues in the NV crystal structure. All known antigenic strains are resolved in partition P07. All class identification (ID) codes contain three characters: the first two characters are GI for all genogroup 1 classes, and they are GII for all genogroup 2 classes. These class IDs identify individual classes occurring at a given ETC position. All the sequences of these classes are shown in Table 1. The hinge region residues and the P domain residues are boldfaced in contrast to the S domain class-specific residues. Residue numbers correspond to that of NV. *, insertions; P0n+, including all class-specific residues of the previous class denoted by the number n.