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''Aspergillus fumigatus'' is a fungus of the genus ''Aspergillus'', and is one of the most common ''Aspergillus'' species to cause disease in individuals with an immunodeficiency. ''A. fumigatus'', a saprotroph widespread in nature, is typically found in soil and decaying organic matter, such as compost heaps, where it plays an essential role in carbon and nitrogen recycling. Colonies of the fungus produce from conidiophores thousands of minute grey-green conidia (2–3 μm) that readily become airborne. For many years, ''A. fumigatus'' was thought to only reproduce asexually, as neither mating nor meiosis had ever been observed. In 2008, however, ''A. fumigatus'' was shown to possess a fully functional sexual reproductive cycle, 145 years after its original description by Fresenius. Although ''A. fumigatus'' occurs in areas with widely different climates and environments, it displays low genetic variation and lack of population genetic differentiation on a global scale. Thus the capability for sex is maintained even though little genetic variation is produced. The fungus is capable of growth at (normal human body temperature), and can grow at temperatures up to , with conidia surviving at —conditions it regularly encounters in self-heating compost heaps. Its spores are ubiquitous in the atmosphere, and it is estimated that everybody inhales several hundred spores each day; typically these are quickly eliminated by the immune system in healthy individuals. In immunocompromised individuals, such as organ transplant recipients and people with AIDS or leukemia, the fungus is more likely to become pathogenic, over-running the host's weakened defenses and causing a range of diseases generally termed aspergillosis. Several virulence factors has been postulated to explain this opportunistic behaviour. When the fermentation broth of ''A. fumigatus'' was screened, a number of indolic alkaloids with antimitotic properties were discovered. The compounds of interest have been of a class known as tryprostatins, with spirotryprostatin B being of special interest as an anticancer drug. ''A. fumigatus'' grown on certain building materials can produce genotoxic and cytotoxic mycotoxins, such as gliotoxin. ==Genome== ''A. fumigatus'' has a stable haploid genome of 29.4 million base pairs. The genome sequences of three ''Aspergillus'' species—''Aspergillus fumigatus'', ''Aspergillus nidulans'', and ''Aspergillus oryzae''—were published in the journal ''Nature'' in December 2005. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Aspergillus fumigatus」の詳細全文を読む スポンサード リンク
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