Bioinformatics analysis and characteristics of glycoprotein G encoded by the newly identified Us4 gene of duck enteritis virus

The US4 open reading frame of the Duck enteritis virus (DEV) encodes glycoprotein G, a protein comprising 459 amino acids with a putative molecular mass of 50.58 kDa. The characteristics of this protein were analyzed through bioinformatics softwares and tools. Glycoprotein G sequence analysis indicates that the protein possesses typical characteristics of membrane glycoproteins containing two transmembrane domains and a N-terminal hydrophobic signal peptide sequence. Through secondary structure presumption, gG consists of extended strand (E) with 28.54% and random coil (C) with 44.23%, in contrast, alpha helix (H) with 16.99% and beta turn (T) with 10.24%, suggesting that DEV-gG has more noncohesive flexibility structures, which always contain B cell dominant epitopes. Furthermore, the result of estimating potential antigenic epitopes shows that gG contains 18 antigenic determinants locating the whole sequence. These results indicate that DEV-gG has good immunogenicity. In conclusion, all the data and consequences will provide a basis for further functional study of DEV-glycoprotein G and provide rational data for the development of new antibodies and immunoassays in the clinical diagnosis of DEV.