A geographically diverse set of isolates indicates two phylogenetic lineages withinStachybotrys chartarum

Abstract

Stachybotrys chartarum is a black mitosporic fungus capable of dense colonization of cellulose-based building materials such as drywall. The presence of S. chartarum in indoor environments has been reported as linked to a variety of alleged environment-related illnesses including infant acute idiopathic pulmonary hemorrhage, although there continues to be insufficient (especially exposure) data to support such associations. We investigated genetic variation among 52 morphologically and geographically diverse, indoor and outdoor isolates of S. chartarum sensu lato using molecular markers based on β-tubulin, calmodulin, elongation factor-1 alpha, and trichodiene synthase genes, as well as the internal transcribed spacer region of nuclear ribosomal DNA. Gene genealogies proved concordant in dividing all isolates into two strongly supported clades. The majority of the variable sites separating these lineages were fixed within each of these clades, and there was no evidence of recombination between genotypes. The results of this study therefore provide strong support for the recognition of two phylogenetic species within S. chartarum sensu lato, and further demonstrate the limitations of morphological characters in delineating monophyletic taxa among morphologically simple fungi.Key words: Stachybotrys atra, cryptic speciation, calmodulin, elongation factor-1 alpha, trichodiene synthase.

Stachybotrys atra BP-A produces alkali-resistant and thermostable cellulases

“…Lane 1, control crude cellulase. The positions of molecular weight standards is indicated 1998), many other isolates are non-toxigenic strains (Nikulin et al 1994;Koster et al 2003). The production of toxins by several strains of this microorganism has probably determined the lack of in-depth studies of cellulose degradation by this fungus.…”

Overview of Stachybotrys (Memnoniella) and current species status

“…Many strains belonged to S. chartarum, as a cellulolytic saprobe with a worldwide distribution (Li and Yang 2005). However, according to previous experience (Andersen et al 2003;Cruse et al 2002;Koster et al 2003Koster et al , 2009), S. chartarum isolates (Fig. 1) certainly include some divergent lineages based on multi-gene analysis, and some taxa might be synonyms of S. chartarum, just like S. atra.…”

“…Taxonomy of the genus Stachybotrys, especially the delineation of some species, even the type species, remains controversial due to the poor condition of the holotypes associated with the type species of the genus and with some other species (Koster et al 2003 2012). Since type specimen for Hyalostachybotrys bisbyi, type species of Hyalostachybotrys is a culture, this genus is also invalid (Art.…”

“…Andersen et al (2003) described this new species as S. chlorohalonata and recognized two chemotypes of S. chartarum on the basis of the three above fragments and phenotypic analyses. Koster et al (2003) used molecular markers based on β-tubulin, calmodulin, elongation factor-1 alpha (EF1-α), and tri5 genes, as well as ITS rDNA to investigate genetic variation among 52 morphologically and geographically diverse, indoor and outdoor isolates of S. chartarum sensu lato. This proved concordant in dividing all isolates into two strongly supported clades.…”

MALDI-TOF mass spectrometry fingerprinting: A diagnostic tool to differentiate dematiaceous fungi Stachybotrys chartarum and Stachybotrys chlorohalonata

“…idiopathic pulmonary hemorrhage Vesper et al, 1999Vesper et al, , 2000 and sick building syndrome (Cooley et al, 1998). For that reason, much effort was directed towards better understanding of the biochemistry and the characterization of Stachybotrys (Andersen et al, 2002(Andersen et al, , 2003Black et al, 2008;Cruse et al, , 2003Koster et al, 2003Koster et al, , 2009Nielsen and Smedsgaard, 2003;Vesper et al, 1999Vesper et al, , 2000. In this study, 19 Stachybotrys isolates covering 3 different species were identified using molecular biological methods and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) fingerprints.…”