Characterization of a Toxin‐Deficient Clostridium perfringens Strain, KZ1340
Characterization of a Toxin‐Deficient Clostridium perfringens Strain, KZ1340
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缺乏毒素的产气荚膜梭菌菌株 KZ1340 的表征
DOI：
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发表时间：
1996
影响因子：
2.6
通讯作者：
H. Hayashi
中科院分区：
文献类型：
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作者：
Tohru Shimizu;K. Ohtani;W. Ba;S. Inui;S. Nakamura;H. Hayashi
产气荚膜梭菌KZ1340以前被归类为斜纹梭菌，是一株来自南极土壤的分离物，被鉴定为不产生α，θ和κ毒素的变异体。经Southern杂交，发现该变异株在pfOA(θ毒素)基因上存在缺陷，但plc(α毒素)和Cola(κ毒素)基因存在于与标准株NCTC8237相同的EcoRI片段上。Northern分析表明，KZ1340中转录了成熟的plc基因，但转录效率低于NCTC8237，而KZ1340中没有成熟的Cola基因。将pFOA和plc基因通过穿梭载体pJIR418导入KZ1340后，pFOA基因得到了成功表达，但plc基因没有得到有效表达，表明pFOA基因和plc基因在KZ1340中的表达存在负调控。毒素缺陷型产气荚膜梭菌KZ1340如果能高效表达，产生少量的胞外毒素，可能是分析pfOA基因和其他梭状芽胞杆菌毒力基因表达的合适宿主。
Clostridium perfringens KZ1340, previously classified as Clostridium plagarum, is an isolate from Antarctic soil, and was identified as an α, θ‐, and κ‐toxin non‐producing variant. On Southern hybridization, the variant was found to be defective in the pfoA (θ‐toxin) gene, but the plc (α‐toxin) and colA (κ‐toxin) genes were present on the same EcoRI fragment as in the standard strain, NCTC8237. Northern analysis revealed that mature plc mRNA was transcribed in KZ1340 though less efficiently than in NCTC8237, while no mature colA mRNA was present in KZ1340. After transformation of the pfoA and plc genes into the KZ1340 via shuttle vector, pJIR418, the pfoA gene was successfully expressed but the plc gene was not efficiently expressed, suggesting that in KZ1340 there is negative regulation of plc gene expression. Toxin‐deficient C. perfringens KZ1340 might be a suitable host for expression analysis of the pfoA gene and other clostridial virulence genes, if expressed efficiently, because it produces a small amount of extracellular toxins.