Prokaryotic Expression And Functional Characteristic Of A Recombinant Fungal Immunomodulatory Protein From Ganoderma Atrum

Ganoderma spp.is traditional Chinese medicinal fungi and has been used by humans for thousands of years in China folk.It contains numerous bioactive natural components,such as polysaccharides,ganoderic acids,ergosterols,proteins,unsaturated fatty acids,vitamins,minerals and etc.Fugal immunomodulatory protein(FIP)is a kind of small molecule protein with immune regulating activity,isolated from higher Basidiomycetes fungi.Until now,ten FIPs have been isolated and identified from Ganoderma lucidum,G.tsugae,Flammulina velutipes,Volvariella volvacea,G.japoncium,G.microsporum,G.sinensis,Trametes versicolor,Nectria haematococca,which were designated as LZ-8/FIP-glu and FIP-LZ9,FIP-gts,FIP-fve,FIP-vvo,FIP-gja,FIP-gmi,FIP-gsi,FIP-tvc and FIP-nha,respectively.FIP from G.atrum,designated as FIP-gat,was a new member of FIPs family.Based on the cloning of FIP-gat gene from G.atrum,in the prtesent study,we firstly constructed the prokaryotic expression cassette pET-30a::FIP-gat,and then transferred it into E.coli BL21 cell for inducing expression.After purification of rFIP-gat,we investigated preliminarily on its agglutinating activities for human breast cancer cell MDA-MB-231.The results showed that FIP-gat gene was successfully expressed and the rFIP-gat expression yields reached to 29.76 mg/L.Furthermore,the rFIP-gat protein exhibited an agglutination activity to MDA-MB-231 cells at the protein concentrations of 5-20 ?g/mL when the cells were cultured for 6-24 h.With the increasing concentration of rFIP-gat and cultured time,the agglutinating activity for MDA-MB-231 cells was shown a enhancement efficiency.The present study would lay the foundation for further research on the rFIP-gat.