致病性猪链球菌2型溶血素基因的克隆与表达

Clone and Expression of Sly Gene from Streptococcus suis Serotype 2

目的:克隆溶血素基因,为评价溶血素的毒力与抗原活性,构建猪链球菌疫苗提供依据。方法:从致病性猪链球菌II型四川资阳分离株基因组中分离溶血素基因,经中间T载体,将其克隆至改造的pGEX-6p1中,最后通过蛋白质电泳和溶血实验检验溶血素的表达及活性。结果:SDS-PAGE结果表明,重组溶血素在5h表达水平最高,10h次之,15h最弱;溶血实验重组菌周围形成明显的透明溶血环。结论:溶血素为分泌性早期表达,具有正常的β溶血活性。

Objective： To clone and evaluate the virulence and protection of suilysin（SLY）, for developing a vaccine against the infective Streptococcus suis type 2（SS2）. Methods： Sly gene was amplified from a SS2 strain isolated in Ziyang, Sichuan, and ligased into T-vector, then transferred into a refined pGEX-6pl without Laclq gene. Protein SDS-PAGE electrophoresis and hemolysis test was used to check the expression and activity of SLY. Results： The SLY expression of recombinant strain was lower by degree for growth at 5 h, 10 h and 15 h, and transparent ring around recombinant strain were observed in electrophoresis and hemolysis test respectively. Conclusion： Secreted SLY was expressed in early stage and exhibited a distinctive β-hemolysis activity.