A combined approach, using molecular and microscopic
techniques, was used to identify the microbi... more A combined approach, using molecular and microscopic techniques, was used to identify the microbiota associated with the Archimedes Palimpsest, an unusual parchment manuscript. SEM analyses revealed the microbial damage to the collagen fibers and the presence of characteristic cell chains typical of filamentous bacteria and fungal spores. Molecular analysis confirmed a homogeneous bacterial community colonizing the manuscript. The phyla Proteobacteria and Actinobacteria were associated with this ancient parchment; the sequences were most related to uncultured clones detected in the human skin microbiome and in ephitelium, and to cultivated species of the genera Acinetobacter and Nocardiopsis. Nevertheless, a great variation was observed among the different sampled areas indicating fungal diversity.
The fungal genus Knufia mostly comprises extremotolerant species from environmental sources, espe... more The fungal genus Knufia mostly comprises extremotolerant species from environmental sources, especially rock surfaces. The draft genome sequence of the rock fungus Knufia petricola presented here is the first whole-genome sequence of the only species among black fungi known to have a nonmelanized spontaneous mutant.
Salt mines are among the most extreme environments as they combine darkness, low nutrient availab... more Salt mines are among the most extreme environments as they combine darkness, low nutrient availability, and hypersaline conditions. Based on comparative genomics and transcriptomics, we describe in this work the adaptive strategies of the true halophilic fungus Aspergillus salisburgensis, found in a salt mine in Austria, and compare this strain to the ex-type halotolerant fungal strain Aspergillus sclerotialis. On a genomic level, A. salisburgensis exhibits a reduced genome size compared to A. sclerotialis, as well as a contraction of genes involved in transport processes. The proteome of A. sclerotialis exhibits an increased proportion of alanine, glycine, and proline compared to the proteome of non-halophilic species. Transcriptome analyses of both strains growing at 5% and 20% NaCl show that A. salisburgensis regulates three-times fewer genes than A. sclerotialis in order to adapt to the higher salt concentration. In A. sclerotialis, the increased osmotic stress impacted processe...
Extremophiles : life under extreme conditions, Jan 12, 2017
Halophilic fungal strains isolated from historical wooden staircase in a salt mine in Austria, an... more Halophilic fungal strains isolated from historical wooden staircase in a salt mine in Austria, and from wall biofilm and soil of a cave in the Coastal Range of the hyperarid Atacama Desert in Chile were characterised and described newly as Aspergillus salisburgensis and Aspergillus atacamensis. Morphological characters including solitary phialides producing solitary conidia and conidia in chains and/or heads suggested affinity to Aspergillus subgenus Polypaecilum. Strains required salt for growth, grew optimally on media with 10-25% NaCl and at 15-28 °C. These values are similar to those observed for Aspergillus salinarus comb. nov. (Phialosimplex salinarum), while the ex-type strains of Aspergillus sclerotialis, Aspergillus chlamydosporus and Aspergillus caninus (all belonging to Aspergillus subgen. Polypaecilum) grew optimally at 0-5% NaCl and showed fastest growth at 28-37 °C. Phylogenetic analyses on the basis of rDNA sequences, RAPD-PCR fingerprint patterns, and cellobiohydrola...
We present a case study of biodeterioration phenomena encountered in parchment-supported manuscri... more We present a case study of biodeterioration phenomena encountered in parchment-supported manuscripts. In this study, our understanding of the physical and chemical changes observed in parchment as a result of fungal and bacteriological attack has been addressed by means of culturing, and through the application of scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX). Two biochemical tests were performed to assess the viability of microorganisms. The luciferine-luciferase method for adenosine triphosphate (ATP) quantification was used to estimate the viability of microorganisms in parchment samples, and a test based on the measurement of fungal β (1-4)-N-acetyl- D-glucosaminidase activity was used to quantify fungal biomass. The purple stains blemishing the manuscript sheets were found to be caused by an attack of bacteria from the order Actinomycetales (presumably of the genus Streptomyces), although the causative agent that had provoked the stains was no lon...
A combined approach, using molecular and microscopic
techniques, was used to identify the microbi... more A combined approach, using molecular and microscopic techniques, was used to identify the microbiota associated with the Archimedes Palimpsest, an unusual parchment manuscript. SEM analyses revealed the microbial damage to the collagen fibers and the presence of characteristic cell chains typical of filamentous bacteria and fungal spores. Molecular analysis confirmed a homogeneous bacterial community colonizing the manuscript. The phyla Proteobacteria and Actinobacteria were associated with this ancient parchment; the sequences were most related to uncultured clones detected in the human skin microbiome and in ephitelium, and to cultivated species of the genera Acinetobacter and Nocardiopsis. Nevertheless, a great variation was observed among the different sampled areas indicating fungal diversity.
The fungal genus Knufia mostly comprises extremotolerant species from environmental sources, espe... more The fungal genus Knufia mostly comprises extremotolerant species from environmental sources, especially rock surfaces. The draft genome sequence of the rock fungus Knufia petricola presented here is the first whole-genome sequence of the only species among black fungi known to have a nonmelanized spontaneous mutant.
Salt mines are among the most extreme environments as they combine darkness, low nutrient availab... more Salt mines are among the most extreme environments as they combine darkness, low nutrient availability, and hypersaline conditions. Based on comparative genomics and transcriptomics, we describe in this work the adaptive strategies of the true halophilic fungus Aspergillus salisburgensis, found in a salt mine in Austria, and compare this strain to the ex-type halotolerant fungal strain Aspergillus sclerotialis. On a genomic level, A. salisburgensis exhibits a reduced genome size compared to A. sclerotialis, as well as a contraction of genes involved in transport processes. The proteome of A. sclerotialis exhibits an increased proportion of alanine, glycine, and proline compared to the proteome of non-halophilic species. Transcriptome analyses of both strains growing at 5% and 20% NaCl show that A. salisburgensis regulates three-times fewer genes than A. sclerotialis in order to adapt to the higher salt concentration. In A. sclerotialis, the increased osmotic stress impacted processe...
Extremophiles : life under extreme conditions, Jan 12, 2017
Halophilic fungal strains isolated from historical wooden staircase in a salt mine in Austria, an... more Halophilic fungal strains isolated from historical wooden staircase in a salt mine in Austria, and from wall biofilm and soil of a cave in the Coastal Range of the hyperarid Atacama Desert in Chile were characterised and described newly as Aspergillus salisburgensis and Aspergillus atacamensis. Morphological characters including solitary phialides producing solitary conidia and conidia in chains and/or heads suggested affinity to Aspergillus subgenus Polypaecilum. Strains required salt for growth, grew optimally on media with 10-25% NaCl and at 15-28 °C. These values are similar to those observed for Aspergillus salinarus comb. nov. (Phialosimplex salinarum), while the ex-type strains of Aspergillus sclerotialis, Aspergillus chlamydosporus and Aspergillus caninus (all belonging to Aspergillus subgen. Polypaecilum) grew optimally at 0-5% NaCl and showed fastest growth at 28-37 °C. Phylogenetic analyses on the basis of rDNA sequences, RAPD-PCR fingerprint patterns, and cellobiohydrola...
We present a case study of biodeterioration phenomena encountered in parchment-supported manuscri... more We present a case study of biodeterioration phenomena encountered in parchment-supported manuscripts. In this study, our understanding of the physical and chemical changes observed in parchment as a result of fungal and bacteriological attack has been addressed by means of culturing, and through the application of scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX). Two biochemical tests were performed to assess the viability of microorganisms. The luciferine-luciferase method for adenosine triphosphate (ATP) quantification was used to estimate the viability of microorganisms in parchment samples, and a test based on the measurement of fungal β (1-4)-N-acetyl- D-glucosaminidase activity was used to quantify fungal biomass. The purple stains blemishing the manuscript sheets were found to be caused by an attack of bacteria from the order Actinomycetales (presumably of the genus Streptomyces), although the causative agent that had provoked the stains was no lon...
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techniques, was used to identify the microbiota associated
with the Archimedes Palimpsest, an unusual parchment
manuscript. SEM analyses revealed the microbial damage to
the collagen fibers and the presence of characteristic cell
chains typical of filamentous bacteria and fungal spores. Molecular
analysis confirmed a homogeneous bacterial community
colonizing the manuscript. The phyla Proteobacteria and
Actinobacteria were associated with this ancient parchment;
the sequences were most related to uncultured clones detected
in the human skin microbiome and in ephitelium, and to
cultivated species of the genera Acinetobacter and
Nocardiopsis. Nevertheless, a great variation was observed
among the different sampled areas indicating fungal diversity.
techniques, was used to identify the microbiota associated
with the Archimedes Palimpsest, an unusual parchment
manuscript. SEM analyses revealed the microbial damage to
the collagen fibers and the presence of characteristic cell
chains typical of filamentous bacteria and fungal spores. Molecular
analysis confirmed a homogeneous bacterial community
colonizing the manuscript. The phyla Proteobacteria and
Actinobacteria were associated with this ancient parchment;
the sequences were most related to uncultured clones detected
in the human skin microbiome and in ephitelium, and to
cultivated species of the genera Acinetobacter and
Nocardiopsis. Nevertheless, a great variation was observed
among the different sampled areas indicating fungal diversity.