野生类型的乳球菌 (Lactococcus lactis) 产生类似于细菌素的益生菌 lysins
Timo M Takala1, Samira Mokhtari1, Susanna L Ahonen1,2
1Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland.
Frontiers in microbiology
|July 31, 2023
概括
来自Lactococcus lactis菌株LAC460的新型菌素具有抗菌活性,作为潜在的III类细菌素. 这些发现扩大了乳酸细菌产生的已知细菌素类型.
科学领域:
- 微生物学 微生物学
- 细菌学 细菌学是一门学科.
背景情况:
- 乳球球菌是一种关键的乳制品起始品种,产生超过40种细菌素,主要是耐热的I和II类.
- 在乳球菌种中没有发现III类细菌素 (热敏,较大的蛋白质).
- 与尾状细菌素不同的是,因其在自解中的作用而通常不被归类为细菌素.
研究的目的:
- 为了研究Lactococcus lactis菌株LAC460.460的抗菌活性.
- 为了确定负责观察到的光学活性的特定分子.
- 确定这些分子是否代表一种新型的细菌菌类.
主要方法:
- 对L. lactis菌株LAC460的基因组测序.
- 鉴定和净化菌素素从培养超浮物.
- 敲除突变体的构建和分析,以评估基因功能.
主要成果:
- 菌株LAC460表现出对其他乳球球菌株的蛋白酶和热敏酸活性.
- 鉴定了三种菌素溶酶 (LysL,LysP和另一个),由菌体区域编码.
- 通过淘汰赛研究,LysL和LysP被证实是抗菌活性的主要媒介.
- 菌株LAC460表现出对自身素的耐药性,使细胞外活动成为可能.
结论:
- 来自L. lactis LAC460的菌素lysL和LysP作为强大的抗菌剂起作用.
- 这些基于素的抗微生物药物代表了III类细菌素的新型潜在类别.
- 这一发现扩大了对乳酸细菌中抗微生物机制的理解.
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