Molecular characterization of the Japanese encephalitis virus representative immunotype strain JaGAr 01.

We determined the full genomic sequence of the Japanese encephalitis virus JaGAr 01 strain and its predicted amino acid sequence. Nucleotide sequence comparison with ten fully sequenced JE strains shows a homology range from 89.62 to 99.49%. Amino acid sequence homologies range from 96.85 to 99.74%. Comparison of amino acid sequences shows a unique amino acid, arginine, for JaGAr 01 at position 123 of the E-protein, while the eight other strains contained serine. Secondary structure prediction by free energy minimization shows a unique structure for JaGAr 01 that includes an RNA segment that is conserved for all flaviviruses. Speculation is made about the role these results may play in the replication and antigenic characteristics of JaGAr 01. Phylogenetic analyses of the E-protein of JaGAr 01 together with 35 other JE strains showed diversity in amino acid characteristics between the prototype strains Nakayama, JaGAr 01 and Beijing-1. Phylogenetic trees computed by neighbor joining and Fitch Margoliash analysis of nucleic acid and protein sequences showed Nakayama and Beijing in one cluster different from JaGAr 01.