Correction to: truncated satratoxin gene clusters in selected isolates of the atranone chemotype of Stachybotrys chartarum (Ehrenb.) S. Hughes.
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SUBMITTER: Ulrich S
PROVIDER: S-EPMC7645536 | biostudies-literature | 2020 May
REPOSITORIES: biostudies-literature
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Correction to: truncated satratoxin gene clusters in selected isolates of the atranone chemotype of Stachybotrys chartarum (Ehrenb.) S. Hughes.
Ulrich Sebastian S Niessen Ludwig L Ekruth Julia J Schäfer Cornelius C Kaltner Florian F Gottschalk Christoph C
Mycotoxin research 20200501 2
The original version of this paper was published with error. The supplementary materials originally provided were not captured during article production. ...[more]
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Project description:The fungus Stachybotrys (S.) chartarum was isolated from culinary herbs, damp building materials, and improperly stored animal forage. Two distinct chemotypes of the fungus were described that produced either high-cytotoxic macrocyclic trichothecenes (S type) or low-cytotoxic atranones (A type). Recently, two distinct gene clusters were described that were found to be necessary for the biosynthesis of either macrocyclic trichothecenes (21 SAT (Satratoxin) genes) or atranones (14 ATR (Atranone) genes). In the current study, PCR primers were designed to detect SAT and ATR genes in 19 S. chartarum chemotype S and eight S. chartarum chemotype A strains. Our analysis revealed the existence of three different genotypes: satratoxin-producing strains that harbored all SAT genes but lacked the ATR gene cluster (genotype S), non-satratoxin-producing strains that possessed the ATR genes but lacked SAT genes (genotype A), and a hitherto undescribed hybrid genotype among non-satratoxin-producing strains that harbored all ATR genes and an incomplete set of SAT genes (genotype H). In order to improve the discrimination of genotypes, a triplex PCR assay was developed and applied for the analysis of S. chartarum and S. chlorohalonata cultures. The results show that genes for macrocyclic trichothecenes and atranones are not mutually exclusive in S. chartarum. Correlation of the new genotype-based concept with mycotoxin production data shows also that macrocyclic trichothecenes are exclusively produced by S. chartarum genotype S strains.
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Project description:Stachybotrys chartarum is a toxigenic fungus that is frequently isolated from damp building materials or improperly stored forage. Macrocyclic trichothecenes and in particular satratoxins are the most potent mycotoxins known to be produced by this fungus. Exposure of humans or animals to these secondary metabolites can be associated with severe health problems. To assess the pathogenic potential of S. chartarum isolates, it is essential to cultivate them under conditions that reliably promote toxin production. Potato dextrose agar (PDA) was reported to be the optimal nutrition medium for satratoxin production. In this study, the growth of S. chartarum genotype S strains on PDA from two manufacturers led to divergent results, namely, well-grown and sporulating cultures with high satratoxin concentrations (20.8 ± 0.4 µg/cm2) versus cultures with sparse sporulation and low satratoxin production (0.3 ± 0.1 µg/cm2). This finding is important for any attempt to identify toxigenic S. chartarum isolates. Further experiments performed with the two media provided strong evidence for a link between satratoxin production and sporulation. A comparison of three-point and one-point cultures grown on the two types of PDA, furthermore, demonstrated an inter-colony communication that influences both sporulation and mycotoxin production of S. chartarum genotype S strains.
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