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Biological Terrorist Agents
Published in Robert A. Burke, Counter-Terrorism for Emergency Responders, 2017
Trichothecene mycotoxins are created by numerous species of fungi. Over 40 toxins are known to be produced by fungi. T-2 is a stable toxin even when heated to high temperatures. Decontamination or disinfection requires very high concentrations of sodium hydroxide and sodium hypochlorite to detoxify the material. Aerosolization would not be a likely method of dissemination because of the potential low toxicity. However, unlike other toxins, the mycotoxins are dermally active. Aerosol dissemination can cause damage by contacting skin and mucous membranes. Once absorbed into the body, it would become a systemic toxin.
Molds
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 5, 2017
William J. Rea, Kalpana D. Patel
Common mycotoxins produced by indoor molds include: (1) The Trichothecenes: A group of mycotoxins that have strong neurotoxic and immunotoxic properties.18 Trichothecenes inhibit protein synthesis and can cause hemorrhage and vomiting. Trichothecenes are produced mostly by Fusarium, Stachybotrys, and Memnoniella. Also, they can damage the immune system, eventually suppressing T-cell and B-cell function, depressing complements and, at times, gamma globulin subsets. They can cause rhinosinutitis, asthma, neurological dysfunction, and vasculitis; (2) Aflatoxin is an immune modulatory agent, which will stimulate T2 that acts primarily on cell-mediated immunity and phagocytic cell function. Aflatoxins are highly carcinogenic mycotoxins produced by some species of Aspergillus; (3) Ochratoxins: carcinogens and kidney toxins produced by some Aspergillus and Penicillium species; (4) Fuminosins are produced by Fusarium species and are carcinogenic, hepatotoxic and may have estrogenic properties; (5) Sterigmatocystin is a liver toxin and immunosuppressant produced by some Aspergillus species; (6) Hemolysin is produced by Stachybotrys and causes blood hemorrhage; (7) Gliotoxin, which has several immunosuppressive properties, is genotoxic and an inducer of apoptotic cell death, can promote demyelination, and promotes increased virulence of fungal infections. Gliotoxins are produced by a number of genera of common fungi including Aspergillus, Penicillium, and Candida; (8) Patulin, which has diverse toxic effects including mutagenicity, genotoxicity, and inducer of oxidative stress. Patulin is produced by a number of species of Aspergillus and Penicillium.17,19–21 Unfortunately, only half of the trichothecene, ochratoxin, aflatoxin, and gliotoxin, can be measured practically for patients through urine.
Blowing in the wind: Bacteria and fungi are spreading from public restroom hand dryers
Published in Archives of Environmental & Occupational Health, 2021
During incubation, plates were checked daily and colonies were photographed. Bacterial and fungal colonies were counted after two and five days of cultivation, respectively. Colonies with different shapes and colors were marked, with only one or a small number of representative colonies picked up for molecular identification. Genomic DNA was extracted using the MasterPure DNA Purification kit (Epicentre, Madison, WI, USA). To avoid the possibility of misidentification of bacterial and fungal colonies based on morphology, DNA extracts from all selected colonies were first tested by PCR using two pairs of universal bacterial 16S rRNA primer pairs 338F-805R and 515F-1350R,17–19 and two pairs of universal fungal ITS primers ITS1F-ITS2R and ITS86F-ITS4R,20,21 as listed in Supplemental Table S1. In addition, selected samples were further amplified by PCR using different combinations of these primers (338F-1350R for bacteria and ITS1F-ITS4r for fungi) to increase the amplicon size and sequence discriminatory capacity. These primers have been widely used to detect bacterial and fungal communities in various environmental samples including air samples.22–25 PCR with different pairs of primers were performed independently, including no template controls (with distilled water). When the species could not be determined based on sequencing results from the above-mentioned PCR products, additional PCR was performed to amplify other genetic loci using primers shared among a few or all known species of the same genus determined based on the results of PCR with universal bacterial or fungal primers (Supplemental Table S1). These loci included the bacterial 23S rRNA gene, superoxide dismutase gene (sodA), aspartate aminotransferase gene (aat) and orotate phosphoribosyltransferase (pyrE) gene, and fungal beta-tubulin (TUB2) gene, trichothecene C-3 deacetylase (tri8) gene, and mitochondrial rRNA small subunit (SSU), cytochrome B (cytB) and cytochrome oxidase (cox). These loci were selected because previous studies12,26–31 have shown them to be suitable for distinguishing bacterial and fungal species involved in this study. All new primers in this study were designed using the Primer3 program at http://bioinfo.ut.ee/primer3-0.4.0, and synthesized commercially by Integrated DNA Technologies, Inc. (Coralville, IA, USA) (Supplemental Table S1). The specificity of these primers was validated by the sequencing results of their PCR products as described below.
Trichoderma after crossing kingdoms: infections in human populations
Published in Journal of Toxicology and Environmental Health, Part B, 2023
Uener Ribeiro dos Santos, Jane Lima dos Santos
Trichoderma species, including T. longibrachiatum, T. koningii and T. citrinoviride, produce trypsin-like and chymotrypsin-like proteases and leu-aminopeptidase activity, depending upon culture conditions (Kredics et al. 2003; Mohd-Tahir et al. 2012). Protease production varies between Trichoderma species. Trichoderma spp. exhibit hemolytic capability (Trabelsi, Hariga, and Khaled 2010). Other virulence factors include production of carotenoid pigments, drug resistance, immunomodulation, mycotoxin production, and formation of volatile trichothecene compounds (Antal et al. 2005; Cobas et al. 2013; Iida et al. 1999; Konstantinovas et al. 2017; Kredics et al. 2003; Mohd-Tahir et al. 2012; Tascini et al. 2016; Trabelsi, Hariga, and Khaled 2010). T. hamatum produces lipase, urease, phosphatase, and catalase enzymes (Mohd-Tahir et al. 2012). Some isolates exhibit limited chymotrypsin-like and leu-aminopeptidase activities, although other isolates lack these activities (Mohd-Tahir et al. 2012). The production of proteases by Trichoderma may be required for pathogenesis during skin infection which result in necrotic and ulceronecrotic lesions (Gautheret et al. 1995; Kredics et al. 2004; Kuhls et al. 1999). Some isolates also produce the mycotoxin Trichodermin which is a small trichothecene compound that was first isolated from T. viride in the 1960s. Trichodermin inhibits protein synthesis (Mohd-Tahir et al. 2012; Wei et al. 1974) and decreases cell proliferation by inducing G0/G1 cell cycle arrest via targeting of the c-Myc transcription factor (Gao et al. 2021).T. viride induces histamine release in human mast cells by production of volatile trichothecene compounds, and affects innate immune cells in a mechanism that is related to induction of hypersensitivity (Larsen et al. 1996). Alamethicin F50, Suzukacillin A and Trichotoxin A-40 antibiotics produced by Trichoderma also induce histamine release in mast cells in vitro (Bessler et al. 1979).Kubicek et al. (2019) examined whether facultatively pathogenic Trichoderma species contained different genetic signatures compared to other Trichoderma species, and demonstrated that the opportunistic Trichoderma species, T. citrinoviride and T. longibrachiatum, share 94 unique genes compared to other Trichoderma spp. that were analyzed. This unique set includes two genes encoding heat shock response protein regulators (Kubicek et al. 2019).