Fig. 3. Comparison of E protein of Zika virus and other flaviviruses.

A). The region of the E protein of ZIKV (H/PF/2013) along with other ZIKV strains is aligned to representative mosquito-transmitted flaviviruses. Approximately 40 residues of Domain 1 centered on the Asn154 glycosylation site are compared. The conserved glycosylation site at Asn153/154 is highlighted in blue. Red arrows represent secondary structures of ZIKV (sheets). The glycosylation motif N-X-S/T is underlined. The sequences for various flaviviruses were obtained from the Virus Pathogen Database and Analysis Resource (ViPR). Virus strains for which structural information was available were chosen where possible. GenBank Genome Accession codes for these viruses are as follows- ZIKV_Uganda_MR766(a): AY632535, ZIKV_Uganda_MR766(b): KU720415; ZIKV_FPolynesia_H/PF/2013: KJ776791; ZIKV_ Brazil_SPH2015: KU321639; DENV 1_SG/07K3640DK1/2008: GQ398255; DENV 2_16681: NC_001474; DENV 3_SG/05K863DK1/2005: EU081190; DENV4_SG/06K2270DK1/2005: GQ398256; WNV_Lineage1_Kunjin_MRM61C: D00246; WNV_Lineage2_NY99: DQ211652; JEV_SA14: D90194 and YFV_Asibi: AY640589. Sequence of the original isolate (ZIKV_MR766) varies based on the information source; it remains unclear whether this strain was glycosylated at N154 at the time of isolation or whether the glycosylation was acquired during passage through mouse brain. The sequences were manually aligned based on the structures of ZIKV and DENV2. B) Superposition of the Cα backbone of the ZIKV and DENV 2 E and M proteins. The DENV 2 proteins are shown in magenta while the ZIKV E protein is shown in cyan and the M protein in yellow. C) Electron density representing the glycan at Asn154. D) Superposition of the loop region surrounding the glycosylation site (ZIKV: 144 -166; DENV2: 144 -161) flanking the Asn154 glycan for ZIKV (cyan) and DENV2 (magenta).