Comparative Mitogenomics of Fungal Species in Stachybotryaceae Provides Evolutionary Insights into Hypocreales

Stachybotrys chartarum is one of the world’s ten most feared fungi within the family Stachybotryaceae, although to date, not a single mitogenome has been documented for Stachybotryaceae. Herein, six mitogenomes of four different species in Stachybotryaceae are newly reported. The S. chartarum mitogenome was 30.7 kb in length and contained two introns (one each in rnl and cox1). A comparison of the mitogenomes of three different individuals of S. chartarum showed few nucleotide variations and conservation of gene content/order and intron insertion. A comparison of the mitogenomes of four different Stachybotryaceae species (Memnoniella echinata, Myrothecium inundatum, S. chartarum, and S. chlorohalonata), however, revealed variations in intron insertion, gene order/content, and nad2/nad3 joining pattern. Further investigations on all Hypocreales species with available mitogenomes showed greater variabilities in gene order (six patterns) and nad2/nad3 joining pattern (five patterns) although a dominant pattern always existed in each case. Ancestral state estimation showed that in each case the dominant pattern was always more ancestral than those rare patterns. Phylogenetic analyses based on mitochondrion-encoded genes supported the placement of Stachybotryaceae in Hypocreales. The crown age of Stachybotryaceae was estimated to be approximately the Early Cretaceous (141–142 Mya). This study greatly promotes our understanding of the evolution of fungal species in Hypocreales.

Isolation and Characterisation of Toxic Secondary Metabolites Produced by Black Mould

<p>Microbial secondary metabolites, commonly called natural products, have been crucial for the progression of modern medicine. Not essential for the basic functions of life, secondary metabolites are instead produced to provide a competitive advantage in the environment. The method of action is commonly toxicity to other species in their environment, thereby harming or killing the competition. These toxic properties have allowed them to be utilised as antimicrobial and antitumor agents, however this same toxicity is able to cause detrimental health effects in humans causing symptoms ranging from minor to life threatening. The black mould Stachybotrys chartarum is capable of producing very toxic secondary metabolites called macrocyclic trichothecenes. Satratoxin G (6) and H (7), are two of the most toxic naturally occurring compounds in the world. This has made S. chartarum a common target when adverse health has been associated with damp and mouldy dwellings. However, there is very little evidence for this link beyond its ubiquity and ability to produce the aforementioned highly toxic macrocyclic trichothecenes. This research investigates S. chartarum and the toxic secondary metabolites it produces, with special emphasis on satratoxin G and H. Different culturing methods and resulting morphology are assessed. The satratoxins were isolated from crude extracts and full characterisation by 1-D and 2-D NMR spectroscopy was done. This process revealed differences from the accepted literature, and spectra are reported herein to aid in future identification. The importance of genetics and the public health implications of mould contamination are also discussed.</p>

Isolation and Characterisation of Toxic Secondary Metabolites Produced by Black Mould

<p>Microbial secondary metabolites, commonly called natural products, have been crucial for the progression of modern medicine. Not essential for the basic functions of life, secondary metabolites are instead produced to provide a competitive advantage in the environment. The method of action is commonly toxicity to other species in their environment, thereby harming or killing the competition. These toxic properties have allowed them to be utilised as antimicrobial and antitumor agents, however this same toxicity is able to cause detrimental health effects in humans causing symptoms ranging from minor to life threatening. The black mould Stachybotrys chartarum is capable of producing very toxic secondary metabolites called macrocyclic trichothecenes. Satratoxin G (6) and H (7), are two of the most toxic naturally occurring compounds in the world. This has made S. chartarum a common target when adverse health has been associated with damp and mouldy dwellings. However, there is very little evidence for this link beyond its ubiquity and ability to produce the aforementioned highly toxic macrocyclic trichothecenes. This research investigates S. chartarum and the toxic secondary metabolites it produces, with special emphasis on satratoxin G and H. Different culturing methods and resulting morphology are assessed. The satratoxins were isolated from crude extracts and full characterisation by 1-D and 2-D NMR spectroscopy was done. This process revealed differences from the accepted literature, and spectra are reported herein to aid in future identification. The importance of genetics and the public health implications of mould contamination are also discussed.</p>

Stachybotrys Chartarum Secondary Metabolots of Poisonic Microzoquary

Filtered culture fluids of the Stachybotrys chartarum strain were exhaustively extracted with ethyl acetate. The iso lated red residue was subjected to column chro matography (silica gel) with gradient elution, resulting in 2 different fractions. Fraction 1-2 consisted of a crystalline material that showed the same parameters of 1H and 13C as the parameters of staxibotrilaktam and staxibotrilaktam А, a derivative of driman's sesquiterpenoid. The structure proposed for this compound was based on spectroscopic data and no indication of the configuration of stereogenic carbon atoms was obtained. The fungus was produced mainly stachybotrys fully characterized derived sesquiterpenoid of drimana.

Natural Compounds Isolated from Stachybotrys chartarum Are Potent Inhibitors of Human Protein Kinase CK2

A large number of secondary metabolites have been isolated from the filamentous fungus Stachybotrys chartarum and have been described before. Fourteen of these natural compounds were evaluated in vitro in the present study for their inhibitory activity towards the cancer target CK2. Among these compounds, stachybotrychromene C, stachybotrydial acetate and acetoxystachybotrydial acetate turned out to be potent inhibitors with IC50 values of 0.32 µM, 0.69 µM and 1.86 µM, respectively. The effects of these three compounds on cell proliferation, growth and viability of MCF7 cells, representing human breast adenocarcinoma as well as A427 (human lung carcinoma) and A431 (human epidermoid carcinoma) cells, were tested using EdU assay, IncuCyte® live-cell imaging and MTT assay. The most active compound in inhibiting MCF7 cell proliferation was acetoxystachybotrydial acetate with an EC50 value of 0.39 µM. In addition, acetoxystachybotrydial acetate turned out to inhibit the growth of all three cell lines completely at a concentration of 1 µM. In contrast, cell viability was impaired only moderately, to 37%, 14% and 23% in MCF7, A427 and A431 cells, respectively.

Synergistic interactions between Stachybotrys chartarum and other indoor fungal species in moisture-damaged houses

The interactions between six commonly occurring fungal species in damp or water-damaged houses in southern California were studied. These fungal species were Alternaria alternata, Aspergillus niger, Chaetomium globosum, Cladosporium herbarum, Penicillium chrysogenum and Stachybotrys chartarum. In the damp building materials, S. chartarum was found to be associated with A. niger, C. globosum, and P. chrysogenum but not with A. alternata and C. herbarum. Stachybotrys chartarum showed strong antagonistic effect against A. alternata and C. herbarum and significantly inhibited in vitro growth of A. alternata and C. herbarum but had no effect on A. niger, C. globosum, and P. chrysogenum. Two trichothecenes, produced by S. chartarum, trichodermin and trichodermol, significantly inhibited spore germination and in vitro growth of A. alternata and C. herbarum but had no effect on A. niger, C. globosum, P. chrysogenum and S. chartarum. In the damp building materials (drywall, ceiling tile, and oak woods), S. chartarum significantly inhibited the growth of A. alternata and C. herbarum and had no effect on the growth and colonization of A. niger, C. globosum, P. chrysogenum in these substrata.

Rapid and selective detection of macrocyclic trichothecene producing Stachybotrys chartarum strains by loop-mediated isothermal amplification (LAMP)

Cytotoxic macrocyclic trichothecenes such as satratoxins are produced by chemotype S strains of Stachybotrys chartarum. Diseases such as stachybotryotoxicosis in animals and the sick building syndrome as a multifactorial disease complex in humans have been associated with this mold and its toxins. Less toxic non-chemotype S strains of S. chartarum are morphologically indistinguishable from chemotype S strains, which results in uncertainties in hazard characterization of isolates. To selectively identify macrocyclic trichothecene producing S. chartarum isolates, a set of sat14 gene-specific primers was designed and applied in a loop-mediated isothermal amplification (LAMP) assay using neutral red for visual signal detection. The assay was highly specific for S. chartarum strains of the macrocyclic trichothecene producing chemotype and showed no cross-reaction with non-macrocyclic trichothecene producing S. chartarum strains or 152 strains of 131 other fungal species. The assay’s detection limit was 0.635 pg/rxn (picogram per reaction) with a reaction time of 60 min. Its high specificity and sensitivity as well as the cost-saving properties make the new assay an interesting and powerful diagnostic tool for easy and rapid testing.

Mold and Yeast-Like Fungi in the Seaside Air of the Gulf of Gdańsk (Southern Baltic) after an Emergency Disposal of Raw Sewage

The aim of this study was to determine the correlation between the meteorological factors and the number of molds and yeast-like fungi in the air in the five coastal towns in the years 2014–2017, and in 2018, after emergency disposal of raw sewage to the Gdańsk Gulf. In the years 2014–2018, a total number of 88 air samples were collected in duplicate in the five coastal towns of Hel, Puck, Gdynia, Sopot, and Gdańsk-Brzeźno. After the application of the (PCA) analysis, this demonstrated that the first principal component (PC1) had a positive correlation with the water temperature, wind speed, air temperature, and relative humidity. The second principal component (PC2) had a positive correlation with the relative humidity, wind speed, wind direction, and air temperature. In 2018, potentially pathogenic mold and yeast-like fungi (Candida albicans, Stachybotrys chartarum complex, Aspergillus section Fumigati) were detected in the seaside air. While the detected species were not observed in the years 2014–2017. We suggest that it is advisable to inform residents about the potential health risk in the event of raw sewage disposal into the water. Moreover, in wastewater treatment plants, tighter measures, including wastewater disinfection, should be introduced.