发酵实践 在菌体中选择热稳定的内素
Frank Oechslin1,2,3, Xiaojun Zhu1,2, Carlee Morency1,2,3
1Département de biochimie, de microbiologie, et de bio-informatique, Faculté des sciences et de génie, Université Laval, Québec City, Canada.
Molecular biology and evolution
|March 15, 2024
概括
菌体内素向Streptococcus thermophilus显示有限的多样性. 一种新的结合基因增强了酶的稳定性和活性,表明乳制品发酵环境中的积极选择.
科学领域:
- 微生物学 微生物学
- 酶学 是一种酶学.
- 进化生物学 进化生物学
背景情况:
- 菌体内素对于细菌细胞壁溶解和菌体释放至关重要.
- 内分泌体表现出多样化的模块化结构,但进化驱动因素仍然不清楚.
- 乳制品发酵剂Streptococcus thermophilus提供了一个专注的生态利基,以研究内的进化.
研究的目的:
- 研究从感染Streptococcus thermophilus的菌体中产生的内素的多样性和进化.
- 确定S. thermophilus endolysins的结构特征及其功能意义.
- 确定是否受乳制品发酵的特定环境条件的影响.
主要方法:
- 来自S. thermophilus菌体的内素的生物信息分析.
- 已识别的内素的结构和功能特征.
- 在不同温度和度下进行酶活性测定.
- 对内素基因的积极选择压力的分析.
主要成果:
- 在S. thermophilus菌体中观察到有限的内素多样性,具有主导的结构类型.
- 在普遍存在的内素结构中发现了一种新的,保存的结合基因.
- 这种模式显著提高了在高温下酶的稳定性和活性.
- 在模仿乳制品发酵的条件下,证明了这种模式的积极选择.
结论:
- 在S. thermophilus中,内素的进化受到限制,有利于适应乳制品环境的特定结构类型.
- 鉴定出的结合基因是高温发酵中内素功能的关键适应.
- 这一发现突显了生态利基和环境因素在塑造菌体编码酶进化的作用.
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