致病菌烟曲霉新基因Afu4g13170生孢致毒相关性初步研究

The function of the Afu4g13170 gene in conidiation and gliotoxin production of pathogenic Aspergillus fumigatus

摘要:

【目的】对烟曲霉Afu4g13170基因功能进行初步研究。【方法】利用Double-joint PCR方法和一步基因敲除技术, 构建Afu4g13170基因缺失突变株。【结果】序列比对表明烟曲霉Afu4g13170蛋白与构巢曲霉Ani04163蛋白和新型隐球菌Gib2蛋白的氨基酸序列相似性为88.6%; 表型分析表明基因破坏使突变株生长迟缓、梗基伸长、孢子分化能力下降, 产孢推迟、产孢量减少, 色素产生量降低; 色谱分析显示基因缺失突变株的产毒能力下降。【结论】烟曲霉Afu4g13170基因可以作为控制曲霉致毒的一个靶位点。

Abstract:

[Objective] The function of the uncharacterized gene Afu4g13170 in Aspergillus fumigatus was ascertained. [Methods] Double-joint PCR method and one-step gene deletion technique were used to generate the A. fumigatus ΔAfu4g13170 mutant. [Results] Amino acid sequence alignment shows that the predicated Afu4g13170 protein has a similarity of 88.6% to Gib2 protein in Cryptococcus neoformans and Ani04163 protein in A. nidulans. The phenotypic analysis indicated that deletion of Afu4g13170 gene results in growth defect and incomplete development of phialides with elongated metulae, delayed and reduced sporulation, and less pigment production. Chromatographic analysis suggested that gliotoxin production is blocked partly by knocking out the Afu4g13170 gene. [Conclusion] Afu4g13170 gene may be used as one of target sites to control the virulence of A. fumigatus.