|Sheer Hyten, Aimee|
Submitted to: Mycological Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/5/2004
Publication Date: 8/3/2004
Citation: Castlebury, L.A., Rossman, A.Y., Sheer Hyten, A.M., Sung, G., Spatafora, J.W. 2004. Multigene phylogeny reveals new lineage for Stachybotrys chartarum, the indoor air fungus. Mycol. Res. 108: 864-872. Interpretive Summary: Fungi that are regarded as molds are often present in buildings with high humidity. One of these molds, Stachybotrys chartarum, is known to produce mycotoxins that may cause non-specific health symptoms. In order to determine the potential health hazards of molds that occur in buildings as well as those that are used in agriculture, it is necessary to know what fungi are closely related to S. chartarum. Because molds reproduce primarily asexually producing millions of tiny spores, knowledge of their hidden sexual reproduction would also be useful in determining how to control them. Five genes of species of Stachybotrys and similar fungi were sequenced and analyzed. It was determined that Stachybotrys is related to fungi that produce mycotoxins including Myrothecium, a fungus being considered as a biological control agent for weeds. In addition, Stachybotrys may have a sexual state in nature that produces small, black perithecia on rotten wood. This research will be used by environmental engineers to develop strategies to control Stachybotrys in buildings and prevent the spread of harmful molds.
Technical Abstract: Stachybotrys chartarum is an asexually reproducing fungus commonly isolated from soil and litter that is also known as an airborne house-inhabiting fungus that can cause serious illness and even death in humans. Despite its economic importance, higher level phylogenetic relationships of Stachybotrys have not been determined nor has a sexual state for S. chartarum been reported. DNA sequences from four nuclear and one mitochondrial gene were analyzed to determine the ordinal and familial placement of Stachybotrys within the Euascomycota. These data reveal that species of Stachybotrys isolates including S. chartarum, Stachybotrys albipes, a species having the sexual state Melanopsamma pomiformis, and species of Myrothecium, and two other tropical hypocrealean species form a previously unknown monophyletic lineage within the Hypocreales that is distinct from all described families. These results suggest that species of Stachybotrys and Myrothecium are closely related and share characteristics with other hypocrealean fungi. In addition, S. chartarum may have a sexual state in nature that consists of small, black, fleshy perithecia similar to Melanopsamma.