spo0A基因在艰难梭菌生长及芽孢形成中的作用

The role of spo0A gene in growth and sporulation of Clostridium difficile

目的了解spo0A基因对艰难梭菌临床分离株生长和芽孢产生的影响。方法采用ClosTron敲除技术构建艰难梭菌临床分离株C25的spo0A基因突变株,分光光度计检测菌液浓度并绘制生长曲线,孔雀绿染色法计数芽孢和营养细胞。结果艰难梭菌临床分离株C25的spo0A基因敲除突变株和敲除前亲代株的48 h生长曲线无明显差异,但突变株不再产生芽孢。结论 spo0A基因是艰难梭菌芽孢形成过程中的关键基因,但并非其生长过程中的主要基因。

Objective To investigate the role of spoOA gene in growth and sporulation of Clostridium diffcile clinical isolates. Methods ClosTron gene knock-out system was used to knock out the spoOA gene of C. difficile strain C25. Bacterial growth curve was plotted by measuring D600 with spectrophotometer in different phases of bacterial growth. Malachite green staining technique was used to count the number of vegetative cells and spores under optical microscope. The sporulation rate was calculated. Results The spoOA mutant and its C25 parental strain showed similar patterns of growth. However, after knock-out of spoOA gene, an asporogenous phenotype was built, while the parental strain could produce spores as usual. Conclusions The spoOA gene plays a key role in sporulation but not growth of C. difficile strain.