Sequence analysis of the VP2 gene hypervariable region of infectious bursal disease viruses from India

Abstract

Attempts have been made to characterize infectious bursal disease virus (IBDV) isolates collected from different parts of India during 1993 to 1999. Phylogenetic analysis was performed on a sequence generated by cycle sequencing comprising the variable region of the VP2 gene of 14 isolates. Indian IBDV isolates had divergence of 0.2 to 4.3% at nucleotide and 0 to 2.2% at amino acid levels among themselves. Nine nucleotide changes were found in Indian IBDV field isolates, resulting in the four specific amino acid changes at 222P-A, 256V-I, 294L-I and 299N-S, reported regularly in very virulent isolates. One of the Indian IBDV isolates, UP1/99, had change D to N at position 212 in the first hydrophilic region. The serine-rich heptapeptide sequence 'SWSASGS' was conserved in all the isolates. Phylogenetically, all Indian field isolates were found to be closely related to very virulent IBDV isolates from Europe, Japan, China and Israel.

Molecular Characterization of Infectious Bursal Disease Virus From Commercial Poultry in Pakistan

“…In recent years amino acid change D212N found in the same hydrophilic region 'A', may also be essential in structural stability of the hypervariable region, VP2 protein [30]. The trend of mutation is followed naturally in the existing genetic pool of Indo-Pak region [8]. Some of US variant and French vvIBDVs matched the similar ongoing change [9,41].…”

“…At nucleotide level, none of Pakistani samples showed 100% similarity. Within each group the local strains reflected divergence less than 2% but intragroup divergence reached up to 8.5% which may be due to wide temporal and geographical differences of these isolates [8]. The Japanese strain D49706.1 differ 4.2% from native vvIBDVs.…”

“…Under high selection pressure in immune populations there is emergence of new viral strains in targeted poultry flock. VP2, structural protein has a major virus neutralizing conformational epitopes in hypervariable region [8][9][10]. Antigenicity and virulence of the IBDV has been studied extensively on the genetic basis to control IBD [11][12][13][14].…”

Characterization of the antigenic, immunogenic, and pathogenic variation of infectious bursal disease virus due to propagation in different host systems (bursa, embryo, and cell culture). I. Antigenicity and immunogenicity

“…The importance of these findings has direct implications on the strategies involved in vaccine preparation and selection (Fussell, 1998). Changes in the pathogenicit y, antigenicity, or immunogenicity of IBDV derived from different host systems have been partially explained by alterations of the viral genome and epitopes (Ismail et al, 1988;Bayliss et al, 1990;Kibenge et al, 1991;Lana et al, 1992;Jackwood & Jackwood, 1994Vakharia et al, 1994;Jackwood & Sommer, 1997Ture et al, 1998;Eterradossi, et al, 1998Eterradossi, et al, , 1999Mundt, 1999;Boot et al, 2000;Kwon et al, 2000;Yamaguchi et al, 2000;Yu et al, 2000;Abdel-Alim & Saif 2001a,b;Brandt et al, 2001;Cavanagh, 2001;Hoque et al, 2001;Jackwood et al, 2001a,b;Kataria et al, 2001;Nagarajan et al, 2001;Toroghi et al, 2001;Van Loon et al, 2002). However, further work is required to gain a better understanding in correlating genomic and protein modifications with changes in the biological properties of IBDV.…”

Genotypic characterization of Indian isolates of infectious bursal disease virus strains by reverse transcription-polymerase chain reaction combined with restriction fragment length polymorphism analysis

“…Th e BspMI cleavage site found in vvIBDV strains correlated with the amino acid position 222 (proline to alanine) in the major hydrophilic peak A of the VP2 hypervariable region. Th is amino acid exchange was conserved in all the vvIBDVs (Brown et al, 1994;Kataria et al, 2001).…”