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新型P335类菌体耐药性源于Lactococcus lactis中假定AutolysinyccB中的删除
Jenny Seiler1, Anne Millen1, Dennis A Romero1
1IFF, Madison, WI 53716, USA.
Viruses
|November 25, 2023
概括
乳球球菌乳糖初始培养中的菌体 (菌体) 耐药性可能来自于yccB基因的突变,这是一个与细胞壁多糖化物 (CWPS) 改变不同的新机制. 这一发现为乳制品发酵中的菌体不敏感性提供了新的见解.
科学领域:
- 微生物学 微生物学
- 食品科学 食品科学 食品科学
- 细菌学 细菌学是一门学科.
背景情况:
- 乳球菌和乳球菌是发酵乳制品生产中必不可少的初始培养物.
- 这些细菌易受菌体 (菌体) 感染,需要开发菌体不敏感的菌株.
- 对于菌体不敏感的突变物 (BIMs) 通常用于克服工业环境中的菌体易感性.
研究的目的:
- 为了表征L. lactis DGCC12699对P335类菌体有抗性的自发BIM.
- 为了确定这些突变的菌素耐药性的遗传基础.
- 为了研究yccB同类物,细胞壁多糖化物 (CWPS) 类型和菌素耐药性之间的关系.
主要方法:
- 对乳球球菌 (Lactococcus lactis) 的自发菌体不敏感突变 (BIMs) 的表征.
- 对yccB基因突变及其与菌体耐药性相关性的遗传分析.
- 对菌体尾部相关的素受体结合蛋白 (Tal-RBP) 变化的研究.
- 细胞壁多糖体 (CWPS) 操作子和糖系转移酶突变的分析.
主要成果:
- L. lactis BIMs中的菌体耐药性归因于yccB基因的YjdB域中的突变,该基因编码了一个假定的自解素.
- 在菌体的合尾关联氨酸受体结合蛋白 (Tal-RBP) 发生变化后,观察到菌体感染力的恢复.
- yccB同源在L. lactis和L. cremoris中广泛存在,并且与特定的细胞壁多糖化物 (CWPS) 类型相关.
- 在cwps操作子中的糖转移酶的切断也赋予了菌体耐药性,但通过与yccB突变不同的机制.
结论:
- 在yccB基因中的突变代表了一种新的机制,可以在乳球球菌中实现细菌 () 耐药性.
- 这种yccB介导的耐药性与细胞壁多糖化物 (CWPS) 生物合成的改变所产生的耐药性不同.
- 这些发现为重要的乳制品初始培养物中菌体敏感性和耐药性的遗传基础提供了新的见解.
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