氧酸盐循环对于真菌毒性是必需的
1Whitehead Institute for Biomedical Research, Nine Cambridge Center, Massachusetts 02142, USA.
Nature
|July 14, 2001
概括
氧酸盐循环对于真菌感染至关重要. 它的关键酶,如异酸酶 (ICL1),在巨细胞相互作用期间被上调,影响Candida albicans的毒性.
科学领域:
- 医学真菌学 医学真菌学
- 微生物病原体的产生
- 分子生物学分子生物学
背景情况:
- 菌 (Candida albicans) 在免疫抑制个体中引起大多数真菌感染.
- 巨细胞和中性粒细胞通常控制菌,但中性衰竭患者非常容易受到感染.
- 了解真菌对免疫细胞的反应对于治疗白病至关重要.
研究的目的:
- 为了识别在宿主免疫细胞相互作用期间激活的真菌基因和代谢途径.
- 为了研究氧酸盐循环在Candida albicans毒性中的作用.
主要方法:
- 使用了Saccharomyces cerevisiae的全基因组表达特征.
- 分析了Candida albicans的基因表达变化,这些变化发生在巨细胞的细胞化后.
- 在小鼠模型中评估了Candida albicans突变体缺乏关键氧酸环酶的毒性.
主要成果:
- 巨细胞体的细胞化诱导了Saccharomyces cerevisiae中的glyoxylate循环基因.
- 在细胞发生后,Candida albicans对异酸酶 (ICL1) 和酸盐合成酶 (MLS1) 进行上调.
- 缺乏ICL1的Candida albicans突变在小鼠中显著降低了毒性.
结论:
- 氧酸盐循环是微生物病变发生过程中重要的代谢途径.
- 异酸酶 (ICL1) 对Candida albicans的毒性至关重要.
- 这种途径的重要性扩展到其他病原体,如结核菌菌.
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