Homology and conservation of amino acids in E-protein sequences of dengue serotypes

ObjectiveTo identify the homology and phylogenetic relationship among the four dengue virus (DENV) serotypes, and conservation of amino acid in E-proteins and to find out the phylogenetic relationship among the strains of four DENV serotypes.MethodsClustal W analysis for homology and phylogram, European molecular biology open software suite for pairwise alignment of amino acid sequences and BLAST-P analysis for various strains of four DENV serotypes were carried out.ResultsHomology of E-protein sequences of four DENV serotypes indicated a close relationship of DENV-1 with DENV–3. DENV–2 showed close relationship with DENV–1 and −3 forming a single cluster whereas DENV–4 alone formed group with a single serotype. In the multiple sequence alignment, 19 amino acid conserved groups were observed. BLAST–P analysis showed more number of 100% similarity among DENV–1 and −3 strains whereas only few strains showed 100% similarity in DENV–4. However, 100% similarity was absent among the DENV–3 strains.ConclusionsFrom the present study, phylogenetically all the four DENV serotypes were related but DENV–1, −2 and −3 were very closely related whereas DENV-4 was somewhat distant from the other three serotypes.