ABSTRACT
Objective:To analyse the physicochemical properties and structure of major privet pollen allergen Lig v 1 using bioinformatics software and provide a reference for choosing suitable recombinant expression system for Lig v 1 and modifying the allergen Lig v 1 experimentally.Methods:The physicochemical properties were analysed by ProtParam,the signal peptide by SignalP 4.1 Server,the transmembrane helix by TMHMM Server v.2.0,the secondary structure by GOR4,MHCⅡepitopes by NetMHCⅡ2.2 Server,B-cell epitopes by ProteanTM 5.01 and the phylogenetic tree by MEGA 6.Results: Privet major pollen allergen Lig v 1 was stable in Escherichia coli and it doesn′t possess any signal peptide and transmembrane helix.Most secondary structures of Lig v 1 were random coils.Potential region of MHCⅡepitope of Lig v 1 was 30-44.Potential B-cell epitopes possess discontinuous and continuous a mino acid sequences.Lig v 1 and its counterparts from Fraxinus excelsior and Olea europaea were clustered into one group.Conclusion:Escherichia coli is the suitable expression system for recombinant Lig v 1.In silico prediction of the epitopes of Lig v 1 provides a reference for modifying the allergen Lig v 1 experimentally.
ABSTRACT
Objective To investigate the in vivo transduction capability of fusion protein PEP-1-EGFP with mice.Methods Two prokaryotic expression plasmids pET15b-EGFP and pET15b-PEP-1-EGFP were constructed and transformed into E.coli BL21(DE3) to express EGFP and fusion protein PEP-1-EGFP,respectively.The expressed EGFP and PEP-1-EGFP were purified with Ni2+-resin affinity chromatography.Five hundred micrograms of EGFP and PEP-1-EGFP fusion protein were injected into mouse through caudal vein,respectively,the mice were euthanized and perfused with PBS 2 hours after administration.Then,the heart,brain,liver,spleen and kidney were removed and sectioned with a cryostat at 7 ?m for visualization with a inverted fluorescent microscope.ResultsThe brain,heart,liver,spleen and kidney injected with PEP-1-EGFP showed bright and homogenous green fluorescence whereas that with EGFP showed no green fluorescence at all.Conclusion The successful expression and purification of PEP-1-EGFP fusion protein and its efficient transduction into mice in vivo provide a basis for the research on transmembrane delivery of macromolecule drugs mediated by the cell-penetrating peptide,PEP-1.