Adv Appl Microbiol
October 2024
Mutualistic ectomycorrhizal symbiosis requires the exchange of signals even before direct contact of the partners. Volatiles, and specifically volatile terpenoids, can be detected at a distance and may trigger downstream signaling and reprogramming of metabolic responses. The late-stage ectomycorrhizal fungus shows high host specificity with its main host spruce, while rarely associations can be found with pine, .
View Article and Find Full Text PDFJ Basic Microbiol
August 2023
Biofilm formation can lead to tolerance against stressors like antibiotics, toxic metals, salts, and other environmental contaminants. Halo- and metal-tolerant bacilli and actinomycete strains isolated from a former uranium mining and milling site in Germany were shown to form biofilm in response to salt and metal treatment; specifically, Cs and Sr exposition led to biofilm formation. Since the strains were obtained from soil samples, a more structured environment was tested using expanded clay to provide porous structures resembling the natural environment.
View Article and Find Full Text PDFEctomycorrhizal communities at young oak, pine, and birch stands in a former uranium mining site showed a low diversity of morphotypes with a preference for contact and short-distance exploration strategies formed by the fungi , , , , , , as well as abundant . In order to have better control over abiotic conditions, we established pot experiments with re-potted trees taken from the sites of direct investigation. This more standardized cultivation resulted in a lower diversity and decreased prominence of .
View Article and Find Full Text PDFThree strains of the complex were isolated from a salty marsh at a former uranium mining site in Thuringia, Germany. The strains from a metal-rich environment were not only highly salt tolerant (up to 20% NaCl), but at the same time could sustain elevated Cs and Sr (both up to 100 mM) concentrations as well as other (heavy) metals present in the environment. During growth experiments when screening for differential cell morphology, the occurrence of guttation droplets was observed, specifically when elevated Sr concentrations of 25 mM were present in the media.
View Article and Find Full Text PDFLight induces the production of ink-blue pentacyclic natural products, the corticin pigments, in the cobalt crust mushroom Terana caerulea. Here, we describe the genetic locus for corticin biosynthesis and provide evidence for a light-dependent dual transcriptional/cotranscriptional regulatory mechanism. Light selectively induces the expression of the gene encoding the gateway enzyme, the first described mushroom polyporic acid synthetase CorA, while other biosynthetic genes for modifying enzymes necessary to complete corticin assembly are induced only at lower levels.
View Article and Find Full Text PDFis an ectomycorrhizal basidiomycete with high host specificity. The slow-growing fungus is able to produce twenty sesquiterpenes, including α-barbatene, sativene, isocaryophyllene, α-cuprenene, β-cedrene, ß-copaene, 4-epi-α-acoradiene, and chamigrene in axenic culture. For the three major compounds, Δ-protoilludene, β-barbatene, and an unidentified oxygenated sesquiterpene ( 218.
View Article and Find Full Text PDFBiomineral formation is a common trait and prominent for soil Actinobacteria, including the genus . We investigated the formation of nickel-containing biominerals in the presence of a heavy-metal-resistant P16B-1. Biomineralization was found to occur both in solid and liquid media.
View Article and Find Full Text PDFThe extreme metal tolerance of up to 130 mM NiSO in Streptomyces mirabilis P16B-1 was investigated. Genome sequencing revealed the presence of a large linear plasmid, pI. To identify plasmid-encoded determinants of metal resistance, a newly established transformation system was used to characterize the predicted plasmid-encoded loci , and .
View Article and Find Full Text PDFThe adaptation to adverse environmental conditions can lead to adapted microbial communities that may be screened for mechanisms involved in halophily and, in this case, metal tolerance. At a former uranium mining and milling site in Seelingstädt, Germany, microbial communities from surface waters and sediment soils were screened for isolates surviving high salt and metal concentrations. The high salt contents consisted mainly of chloride and sulfate, both in soil and riverbed sediment samples, accompanied by high metal loads with presence of cesium and strontium.
View Article and Find Full Text PDFGenetic manipulation for generating knock-out experiments is essential in deciphering the precise function of a gene. However, dikaryotic fungi pose the inherent challenge of having two allelic versions of each gene, one in each nucleus. In addition, they often are slow-growing and do not withstand protoplasting, which is why Agrobacterium tumefaciens-mediated transformation has been adapted.
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