2019-2023年华东地区猫泛白细胞减少症病毒的遗传变异及分子流行特征分析OA

In order to understand the molecular genetic variation of FPV in East China,28 samples of suspected cat panleukopenia in East China were collected,and the full-length FPV VP2 genes of the 28 strains were amplified and sequenced.The results showed that the homology of the 28 FPV VP2 genes was 98.90%-100.00%,and the homology with the FPV vaccine strain(CU-4)was 99.02%-99.54%;phylogenetic analysis showed that 6 of the 28 strains were located in the same branch with the vaccine strain,while the remaining 22 strains were distant from the vaccine strain.Key amino acid analysis showed that there was a mutation from alanine(A)to serine(S)at the 91 site in VP2 protein for 22 strains.The molecular docking of VP2 protein and transferrin receptor(TfR)showed that the hydrogen bonds and salt bridges in the formation of FPV-VP2-91S/TfR complex were significantly more than those in the formation of FPV-VP2-91A/TfR complex,indicating that the binding force of VP2 protein to TfR was enhanced after the 91st site was mutated to S;the molecular epidemiological characteristics showed that the mutation rate of the 91st site of FPV VP2 protein in China increased from 2017 to 2023.Except for the absence of 91S mutant strains in southern China,there were 91S mutant strains in other regions in China,and the highest in East China,,accounting for 71.95%.The 91st site of FPV VP2 protein was S,which has become the main molecular feature of FPV epidemic strains in East China.This study enriches the molecular epidemiological investigation data of FPV in East China,and provides theoretical basis and key targets for exploring new strategies for the diagnosis,prevention and treatment of immunosuppressive diseases.