第二种类型脂肪酸合成不是适合的抗生素点,用于阳性病原体
Sophie Brinster1, Gilles Lamberet, Bart Staels
1Institut Cochin, Université Paris Descartes, CNRS (UMR 8104), Paris, France.
Nature
|March 6, 2009
概括
针对脂肪酸合成II (FASII) 途径的抗生素开发是有缺陷的. 外源性脂肪酸,就像人体血清中的脂肪酸一样,允许细菌绕过FASII抑制,使这些药物对阳性感染无效.
科学领域:
- 微生物学 微生物学
- 药物发现 药物发现 药物发现
- 生物化学 生物化学
背景情况:
- 第二类脂肪酸合成 (FASII) 途径被认为是细菌生存的关键.
- 针对FASII的抗菌药物已经显示出对多抗性格拉姆阳性细菌的承诺.
研究的目的:
- 调查针对抗生素开发的FASII途径的基本有效性.
- 为了确定外源性脂肪酸是否能够克服格兰阳性病原体的FASII通路抑制.
主要方法:
- 在体外和体内实验中使用格拉姆阳性细菌病原体 (Streptococcus,Enterococcus,Staphylococcus).
- 在外源性脂肪酸和人血清的存在下,评估细菌生长和FASII基因表达.
- 在Streptococcus agalactiae中生成和分析FASII向基因删除突变体.
主要成果:
- 外源性脂肪酸在人体血清中容易存在,有效地绕过抗菌药物抑制FASII通路.
- 主要的格拉姆阳性病原体在与外源性脂肪酸一起供应时克服药物诱导的FASII抑制.
- 在Streptococcus agalactiae感染期间,即使基因被删除,也发现FASII通路酶在体内可用.
结论:
- 开发针对FASII途径的抗生素的战略是根本上有缺陷的,原因是绕过机制.
- 人体血清作为脂肪酸的重要来源,损害了FASII向药物的有效性.
- 基于FASII的抗微生物药物可能无法有效治疗由格拉姆阳性病原体引起的败血症.
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