Kamei K, Watanabe A
Research Center for Pathogenic Fungi and Microbial Toxicoses, Chiba University, Japan.
Med Mycol. 2005 May;43 Suppl 1:S95-9. doi: 10.1080/13693780500051547.
Aspergillus fumigatus is known to produce various immunosuppressive mycotoxins including gliotoxin. However, none of these mycotoxins has been confirmed as being directly related to the pathogenesis of aspergilli. Recent studies have made substantial progress in the determination of mycotoxins as virulence factors. Gliotoxin was found to be produced much faster than previously believed under certain culture conditions, such as at 37 degrees C and under high oxygen content, which is close to the environment in the host. Gliotoxin was also found to be detectable in the sera of aspergillosis mice and of aspergillosis patients. Based on these findings, it is becoming evident that gliotoxin is produced in the infected organs of patients of aspergillosis at a significant level. In addition to these known mycotoxins, A. fumigatus produces many mycotoxins apparently different from known toxins. From the aspect of gene analysis, the deletion of laeA was found to block the expression of metabolic gene clusters such as sterigmatocystin, and the gene is also expected to be related to the production of gliotoxin. The significance of mycotoxins as virulence factors will hopefully be clarified in the near future.
已知烟曲霉会产生多种免疫抑制性霉菌毒素，包括gliotoxin（Gli毒素）。然而，这些霉菌毒素均未被证实与曲霉菌的发病机制直接相关。最近的研究在确定霉菌毒素作为毒力因子方面取得了重大进展。发现在某些培养条件下，如37摄氏度和高氧含量（接近宿主体内环境），Gli毒素的产生速度比以前认为的要快得多。还发现在曲霉病小鼠和曲霉病患者的血清中可检测到Gli毒素。基于这些发现，越来越明显的是，Gli毒素在曲霉病患者的感染器官中大量产生。除了这些已知的霉菌毒素外，烟曲霉还产生许多明显不同于已知毒素的霉菌毒素。从基因分析的角度来看，发现缺失laeA会阻断诸如柄曲霉素等代谢基因簇的表达，并且该基因也有望与Gli毒素的产生有关。霉菌毒素作为毒力因子的重要性有望在不久的将来得到阐明。
