烟曲霉sho1、pbs2基因额外拷贝对几种应激能力的影响  

The effect of extra copies of sho1 or pbs2 gene on the adaptive ability of Aspergillus fumigatus to several stresses

作　　者：马冬梅[1] 季雅娟[1] 阳芳[1] 刘伟[1] 万喆[1] 李若瑜[1] 

机构地区：[1]北京大学第一医院皮肤科 北京大学真菌和真菌病研究中心,北京100034

出　　处：《中国真菌学杂志》2012年第4期193-198,共6页Chinese Journal of Mycology

基　　金：国家自然科学基金(30930006)

摘　　要：目的构建烟曲霉额外拷贝菌株,了解额外拷贝烟曲霉sho 1、pbs 2基因能否增强菌株对高渗透压、过氧化氢(H2O2)、碱性pH、刚果红应激的抵抗能力,探讨HOG通路(high osmolarity glycerol pathway)参与的应激反应。方法用原生质体法构建分别含有烟曲霉sho 1、pbs 2基因的额外拷贝菌株,采用Real-time PCR方法检测额外拷贝株中sho 1、pbs 2的表达情况。观察并比较缺陷株、额外拷贝株对NaCl(1 mol/L)、H2O2(5 mmol/L)、刚果红(400 mg/L)及碱性pH(10.0)应激的反应。结果获得了含有烟曲霉sho 1、pbs 2基因的额外拷贝菌株MCsho1、MCpbs2,和含空白质粒的对照株Empty。额外拷贝株sho 1、pbs 2的表达水平增高,对NaCl(1 mol/L)、H2O2(5 mmol/L)、刚果红(400 mg/L)、碱性pH(10.0)应激的抵抗强于Empty。MCpbs2对这些应激的抵抗较MCsho1更显著。烟曲霉缺陷株△sho 1、△pbs 2对NaCl(1 mol/L)、H2O2(5mmol/L)、碱性pH(10.0)的敏感性高于野生株AF293。△sho 1对刚果红(400 mg/L)的敏感性高于野生株,△pbs 2对刚果红的敏感性与野生株比,无显著差别。结论额外拷贝烟曲霉sho 1或pbs 2基因能增强菌株对高渗透压、氧化压力、刚果红、碱性pH应激的抵抗能力。Objective To explore the role of extra copies of sho 1 or pbs 2 in resistance to hyperosmotic stress,oxidative stress, cell wall stress and alkaline pH stress in A. fumigatus. Methods The reconstructed plasmid harboring a sho 1 gene or a pbs 2 gene were transformed into A.fumigatus by using protoplast transformation method and the resulting strains were designated MCshol or MCpbs2. RT-PCR was used to detect the expression levels ofsho I in MCshol andpbs 2 in MCpbs2 strains. Then strains harboring extra copies as well as sho 1 andpbs 2 deleted mutants were treated with NaCl, H2O2 , Congo red and alkaline pH stresses and the re- sistance phenotypes were observed. Results Mutants harboring extra copies of sho 1 or pbs 2 showed higher expression levels of sho 1 orpbs 2 respectively. Extra copies of sho 1 or pbs 2 conferred resistance to NaCl （ 1 mol/L）, H2O2 （5 mmol/L）, Congo red （400 mg/L） or alkaline pH （10.0）stress. sho 1 and pbs 2 deleted mutants showed higher sensitivity to NaCl （1 mol/L） ,H2O2 （5 mmol/ L） and alkaline pH （10.0）stress than the wild strain. A pbs 2 deleted mutant showed similar sensitivity to Congo red （400mg/L） compared to the wild strain. Conclusion Extra copies of sho 1 or pbs 2 conferred resistance to hyperosmotic stress, oxidative stress, cell wall stress and alkaline pH stress in A. fumigatus.

关 键 词：烟曲霉 sho 1 PBS 2 渗透应激 氧化应激 刚果红 碱性pH 

分 类 号：R379.6[医药卫生—病原生物学]