Study On The Function Of RAlb-34k2 Recombinant Protein Adhesion To Bacteria And Cells

Objective: To investigate the effects of Aedes albopictus saliva protein rAlb-34k2 on the growth of Escherichia coli?E.coli?and Staphylococcus aureus?S.aureus?and its adhesion to various host cells,which are the targets infected by the type 2 dengue virus strain?DENV-2?.Methods: 1)Co-incubated with E.coli,Acinetobacter baumannii?A.baumannii?,Group A ?-hemolytic streptococci?GAS?,Pseudomonas aeruginosa?PAE?and S.aureus,rAlb-34k2 protein adhering to microorganism were detected by western blot;The proliferation of E.coli and S.aureus treated with different concentration of rAlb-34k2 protein were analyzied by spectrophotometric method.2)The infection rate of BHK-21 cells infected by DENV-2 in presence of rAlb-34k2 protein or heated-inactive rAlb-34k2 protein at the early stage was evaluated by indirect immunofluorescence.The adhesion effect of rAlb-34k2 protein to BHK-21,U87,Raw264.7 and Ha Cat were analyzed throught western blot or indirect immunofluorescence method.Results:?1?Preliminary study on the adhesion of rAlb-34k2 to various bacteria:? r Alb-34K2 protein can bind to E.coli,A.baumannii,PAE and S.aureus,but not to GAS;? The growth of E.coli in the ralb-34k2 protein Groups?under the concentration with 137 ng/?L and 112 ng/?L,respectively?was obviously inhibited.Compared with the PBS control group,the average inhibition growth rate was 68.7% and 66.4% under these two concentrations in 24h?n=5?.Moreover,this growth inhibition effect was independent on Ca²⁺,contrasting to the r Alb-CTL2 recombinant protein,which promoted the growth of E.coli in presence of Ca²⁺.?Contrary to the growth inhibition effect on E.coli,the protein that has certain potential to promote the growth of S.aures,whose OD₆₀₀ value increased from 0.616 to 1.504 within 16 h.?2?Preliminary study on the adhesion of rAlb-34k2 to DENV-2 target cells: ? The infection ratio of BHK-21 cells infected by DENV-2 conbinated with the rAlb-34k2 protein was significantly higher than that of BHK-21 cells treated with heated-inactive rAlb-34k2 protein and that of the blank control?n=13,p<0.001?.? The adhesion effect of rAlb-34k2 protein to BHK-21 cells was in a dose-dependent manner.However,the adhesion effect of rAlb-34k2 protein was not inhibited by the specific anti-rAlb-34k2 antibody.Moreover,the rAlb-34k2 protein also recognized the U87,Raw264.7,and Ha Cat cells,which were the viral target cells for DENV-2.Conclusion: The Aedes albopictus saliva rAlb-34k2 protein,which could identify and attach to ligands of bacteria and various arboviral target cells.