The VP2 gene of infectious bursal disease virus (IBDV) Chinju which was previously detected in Chinju, Korea was cloned and sequenced to establish the information for the development of genetically engineered vaccines and diagnostic reagents against IBDV. The nucleotide sequence of the entire Chinju VP2 gene consisted of 1,356 bases long encoding 452 amino acids in a single open reading frme (ORF). It consisted of 368 adenine (27.1％), 363 cytosine (26.8％), 339 guanine (25.0％) and 286 thymine (21.1％) residues. The predicted M_(r) of the Chinju VP2 protein was 48 kDa, and the protein contained 13 phoshorylation sites by protein kinase C, casein kinase Ⅱ or tyrosine kinase, whereas 3 asparagine-linked blycosylation sites were recognized.
The nubleotide sequence of Chinju VP2 ORF had a very close phylogenetic relationship with 98-99％ homology to that of the very virulent IBDVs (vvIBDVs) HK46, OKYM, D6948, UK661, UPM97/61 and BD3/99. Also, the Chinju VP2 protein revealed a very close phylogenetic relationship with 99-100％ homology to that of these vvIDVs. The Chinju VP2 protein had 100％ amino acid identity in the variable region of residues 206-360 with that of the D6948, HK46, OKYM and UK661, as well as 100％ identity in two hypervariable regions of residues 212-224 and 314-324 with those of the D6948, HK46, OKYM, UK661, UPM97/61 and BD3/99. The amino acid sequence of the chinju VP2 protein contained a serine-rich heptapeptide of SWSASGS as in these vvIBDVs.
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