A study of recombinant Dunaliella salina vaccine against dental caries—Transform the chimera gene encoding SBR-CT~(△A1) into Dunaliella salina cells by ultrasonic treatment

AIM:To construct recombinant Dunaliella salina vaccine against dental caries,which carried the chimera gene encoding SBR-CT △A1.METHODS:Sensitivity of wild Dunaliella salina to herbicide phosphinothricin was observed.Recombinant plant expressing plasmid pROSB carrying the gene encoding chimera SBR-CT △A1 and bar gene was transformed into the Dunaliella salina cells by ultrasonic treatment.The genomic DNA of Dunaliella salina was extracted by CTAB method and analyzed by PCR and Southern blot hybridization.The total RNA was extracted by trizol and the transcription of the foreign gene was analyzed by RT-PCR.RESULTS:Herbicide phosphinothricin completely suppressed the growth and proliferation of Dunaliella salina cells in liquid medium at a dose of 6.0 mg/L and 8.0 mg/L in solid medium. Transformants were gained.1.9 kb fragments which consisted with the gene encoding SBR-CT △A1 in size were amplified from the transgenic Dunaliella salina genome by PCR.Total RNA was analysed by RT-PCR. Positive signal fragments were gained by Southern blot hybridization.CONCLUSION:The gene encoding chimera SBR-CT △A1 is integrated into the genome of Dunaliella salina and transcription is normal.