The response to a specific germinant by Bacillus anthracis spores in primary mouse macrophages is modulated by a protein encoded on the pXO1 plasmid.
The response to a specific germinant by Bacillus anthracis spores in primary mouse macrophages is modulated by a protein encoded on the pXO1 plasmid.
复制标题
原代小鼠巨噬细胞中炭疽芽孢杆菌孢子对特定萌芽的反应由 pXO1 质粒上编码的蛋白质调节。
DOI：
10.1007/s00203-008-0403-5
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发表时间：
2008
影响因子：
2.8
通讯作者：
Hu,Haijing
中科院分区：
文献类型：
--
作者：
Aronson,ArthurI;Hu,Haijing
在纯化的炭疽芽孢杆菌孢子的外壳提取物中发现了命名为Cot 43的炭疽芽孢杆菌pXO 1质粒编码蛋白。Cot 43是一个与那些在孢子形成磷酸化中起磷酸酶作用的蛋白相关的三肽重复结构域蛋白，并且是感受态和致病因子的调节剂。Cot 43的合成开始于sigmaA启动子下游的晚期指数期（如通过RACE定位的），并且其存在至少直到形成期白色内生孢子。Cot 43与炭疽芽孢杆菌孢子的结合具有特异性，因为从克隆基因产生Cot 43的蜡状芽孢杆菌在孢子衣提取物中几乎没有这种蛋白。此外，Cot 43是由B.在葡萄糖-酵母提取物和营养型产孢培养基中，炭疽菌的孢子形成程度相同，但前者基本上不形成孢子。在巨噬细胞中的炭疽孢子中，由具有cot 43破坏的突变体产生的孢子在体外和原代小鼠巨噬细胞中比Sterne菌株孢子更早和更广泛地萌发以响应组氨酸。由于Cot 43的存在而导致的萌发延迟将增强孢子存活，从而增加成功感染的机会。
ABacillus anthracisSterne pXO1 plasmid-encoded protein designated Cot43 was found in coat extracts of purified spores. Cot43 is a tetratricopeptide repeat domain protein related to those which function as phosphatases in the sporulation phosphorelay and as regulators of competence and pathogenic factors. The synthesis of Cot43 began in the late exponential phase downstream from a sigmaA promoter (as mapped by RACE) and it was present at least until the formation of phase white endospores. There was specificity in the association of Cot43 withB.anthracisspores sinceBacilluscereusproducing Cot43 from a cloned gene had very little of this protein in spore coat extracts. In addition, Cot43 was synthesized byB. anthraciscells to the same extent in glucose-yeast extract and nutrient sporulation media, but was essentially absent from spores formed in the former.l-histidine is an important germinant forB. anthracisspores in macrophages, Spores produced by a mutant with a disruption ofcot43germinated in response tol-histidine both in vitro and within primary mouse macrophages earlier and more extensively than Sterne strain spores. The germination delay due to the presence of Cot43 would enhance spore survival and thus increase the chances for a successful infection.