DNA Cloning and Sequence Analysis of A TTV Isolated in W uhan
Abstract: A T1 DNA fragment was obtained from W uhan patient serum by PCR,which was cloned into plasmid pMDl8—-T and analyzed by sequencing combined with computer techniques comparing withother isolated strains.The results reveal that this DNA fragment consists of 1 333 base pairs containing whole Trv ORF2 and partial ORFI coding regions, the DNA and deduced amino acid sequence are highly homogenous with those of 1TrV la type.ORF2 peptide consists of 202 amino acids. whose parts of N terminal and C term inal have comparatively high hydrophilic and strongly antigenic characters than middle part.Th e part near N term inal contains a typical tyrosine kinase phosphorylation site(RARDWPGY,38-45aa) and 3 potential protein kinase C phosphorylation sites, the structure in N terminal part is mainly仅helices:while the part near C term inal contains proline rich region and 3 consecutive N-myristoylation sites,the structure in C terminal part is mainly B turns.We infer that the ORF2 protein maybe a phospholated Protein