Metabolites of Trichoderma species isolated from damp building materials

Abstract

Buildings that have been flooded often have high concentrations of Trichoderma spores in the air while drying. Inhaled spores and spore and mycelial fragments contain large amounts of fungal glucan and natural products that contribute to the symptoms associated with indoor mould exposures. In this study, we considered both small molecules and peptaibol profiles of T. atroviride, T. koningiopsis, T. citrinoviride, and T. harzianum strains obtained from damp buildings in eastern Canada. Twenty-residue peptaibols and sorbicillin-derived metabolites (1-6) including a new structure, (R)-vertinolide (1), were characterized from T. citrinoviride. Trichoderma koningiopsis produced several koninginins (7-10), trikoningin KA V, and the 11-residue lipopeptaibols trikoningin KB I and trikoningin KB II. Trichoderma atroviride biosynthesized a mixture of 19-residue trichorzianine-like peptaibols, whereas T. harzianum produced 18-residue trichokindin-like peptaibols and the 11-residue harzianin HB I that was subsequently identified from the studied T. citrinoviride strain. Two α-pyrones, 6-pentyl-pyran-2-one (11) and an oxidized analog (12), were produced by both T. atroviride and T. harzianum. Aside from exposure to low molecular weight natural products, inhalation of Trichoderma spores and mycelial fragments may result in exposure to membrane-disrupting peptaibols. This investigation contributes to a more comprehensive understanding of the biologically active natural products produced by fungi commonly found in damp buildings.

New 1,3-benzodioxin-4-ones from Synnemapestaloides ericacearum sp. nov., a biosynthetic link to remarkable compounds within the Xylariales

“…fici metabolites possessing a 1,3-benzodioxin-4-one scaffold, their biogenesis has been critically evaluated [ 39 , 41 , 43 , 44 ]. Similar Diels-Alder biosynthetic schemes have also been reported for sorbicillin-derived metabolites from the Trichoderma section Longibrachiatum [ 45 – 47 ].…”

New 19-Residue Peptaibols from Trichoderma Clade Viride

“…Trikoningin KA V, identified firstly from T. koningii [ 40 ], is a peptaibol sequence positionally isomeric with sequences Pept-Vb, -VIb, and -VII. This compound was also found to be produced by T. koningiopsis , along with the 11-residue lipopeptaibols trikoningin KB I and KB II [ 18 ]. Trichostrigocins were previously identified from T. strigosum [ 41 , 42 , 43 ] and later also from the extracts of T. paraviridescens and T. trixiae as trichostrigocin-like compounds [ 26 ].…”

“…The information available in the literature about the peptaibol profiles of T. koningiopsis and T. gamsii is limited. Peptaibols produced by T. koningiopsis were previously identified as trikoningin KA V, together with other 11-residue compounds, trikoningin KB I and KB II [ 18 ]. To the best of our knowledge, other peptaibol compounds produced by T. koningiopsis were not previously reported in the literature.…”

Effects of Ventilation Improvement on Measured and Perceived Indoor Air Quality in a School Building with a Hybrid Ventilation System

“…Cellulolytic fungi that require high water content to survive, such as Trichoderma species, are well adapted to colonize water-damaged buildings. Members of this genus are often found on wet manufactured wood and gypsum boards from schools and public buildings [ 14 , 15 ]. Building materials contaminated with Trichoderma species emit high amounts of conidia into the indoor air [ 15 ].…”

“…Members of this genus are often found on wet manufactured wood and gypsum boards from schools and public buildings [ 14 , 15 ]. Building materials contaminated with Trichoderma species emit high amounts of conidia into the indoor air [ 15 ]. Conidia and hyphal fragments containing toxic peptaibols have been shown to provoke histamine release and disrupt the membranes of exposed target cells [ 15 , 16 ].…”