negative strain meaning in English

负冲击响应谱
负应变

4 . effect of resolution vector on the expression of pesticidal crystal protein genes this work successfully introduced pesticidal crystal protein genes into crystal negative strain bmb171 by using resolution shuttle vectors . after resolution , the expression of cry1ac and cry 1c genes have no obvious change , but the expression of cry3a genes has great increase in the same condition
解离反应对杀虫晶体蛋白基因表达的影响成功地利用解离载体将crylac10 ， crylc和cry3a基因导入苏云金芽胞杆菌无晶体突变株， crylac和crylc基因解离前后的表达量和杀虫毒力未见明显变化， cry3a基因在相同条件下则表达量有所提高，至于为何只对基因cry3a有作用尚不清楚，国内外也未见有人作相关报道。
Effect of cry3a promoter on expression by using resolution vector , the cry1ac and cry1c genes with cry3a promoter or it itself promoter were introduced into b . thuringiensis crystal negative strains . the expression of these strains is quit similar , however , the expression of cry 1 ac and crylc with different promoter in same cell has no complete inhibition
Cry3a启动子对基因表达的影响利用解离载体将带cry3a启动子的crylac10和crylc基因导入苏云金芽胞杆菌无晶体突变株，基因的表达和杀虫活性与带自身启动子的基因的表达相近。