候选素氨基酸序列的变化会影响毒性和宿主反应
Don N Wickramasinghe1, Claire M Lyon1, Sejeong Lee1
1Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, United Kingdom.
mBio
|July 2, 2024
概括
坎迪达菌感染会导致严重的健康问题. 这项研究在Candida物种中发现了candidalysin毒素的新变异,揭示了它们破坏宿主细胞和影响感染严重性的能力的差异.
科学领域:
- 医学真菌学 医学真菌学
- 分子生物学分子生物学
- 宿主-病原体相互作用
背景情况:
- 每年有数以百万计的粘膜感染是由 *Candida albicans* 引起的.
- 胺毒素是一种毒素,破坏宿主细胞膜的稳定,导致疾病和免疫病理.
- 之前的研究已经在*C. albicans*,*C. dubliniensis*和*C. tropicalis*中发现了候选素.
研究的目的:
- 为了识别和描述 *C. albicans*, *C. dubliniensis* 和 *C. tropicalis* 中的候选素变体.
- 评估已识别的候选分析素变体的生物活性和生物物理性质.
主要方法:
- 从182种C. albicans,10种C. dubliniensis和78种C. tropicalis分离物中分析了ECE1基因序列.
- 应用于皮细胞的候选素变体,以评估细胞损伤,代谢活动和信号通路.
- 生物物理分析以确定与脂质双层和膜透性的变体相互作用.
主要成果:
- 在*C. albicans*中发现了10种候选素变异,在*C. dubliniensis*中发现了3种,在*C. tropicalis*中发现了2种.
- kandidatalysin 变体对上皮细胞表现出不同的影响,包括损伤的变化,流入,MAPK 信号和细胞因子分泌.
- 生物物理研究表明,变体具有与膜相互作用和透的独特能力.
结论:
- 在医学上相关的*Candida*物种中,候选素氨基酸序列的物种内变异很普遍.
- 已识别的候选素变异具有不同的生物活性,影响病原性.
- 了解候选酶的变异对于理解 *Candida* 病变和开发向疗法至关重要.
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