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... 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.
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.
Research Interests:
Research Interests:
Research Interests:
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... 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 availability, and hypersaline conditions. Based on comparative genomics and transcriptomics, we describe in this work the adaptive strategies of the... 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...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
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... 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...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
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... 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...
The Capuchin Catacombs of Palermo contain over 1800 preserved bodies spanning the 16th-20th centuries A.D., many of which now show serious evidence of biodeterioration. In order to protect these remains, an extensive microbiological and... more
The Capuchin Catacombs of Palermo contain over 1800 preserved bodies spanning the 16th-20th centuries A.D., many of which now show serious evidence of biodeterioration. In order to protect these remains, an extensive microbiological and molecular investigation was performed to clarify which biological agents are involved in the ongoing deterioration. Within the framework of the “Sicily Mummy Project”, samples were taken from skin, muscle, bone, hair, clothing and stuffing materials. Additional samples were removed from the surrounding wall materials, many of which display an unknown, intriguing rosy discoloration. Finally, air samples were taken to investigate the impact of this microbial contamination on the indoor air quality. The results obtained confirmed the presence of a heavy mould contamination. In some areas of the crypt the fungal spores in the air reached more than 2000 spores/m3. This high concentration of spores is not conducive to the conservation of the human remains ...
Research Interests:
A gram-positive strain identified as Arthrobacter globiformis CECT 4500, tolerant to up to 1 M nitrate, was isolated from the grounds of a munitions factory. Under strict aerobic conditions, this bacterium used a wide variety of C-sources... more
A gram-positive strain identified as Arthrobacter globiformis CECT 4500, tolerant to up to 1 M nitrate, was isolated from the grounds of a munitions factory. Under strict aerobic conditions, this bacterium used a wide variety of C-sources to obtain the energy required for growth, which took place when the nitrate concentration in the medium was below 150 mM. Cells of this bacterium growing in the absence of nitrate were seen as individual cells or forming pairs, whereas cells grown in the presence of nitrate formed short filaments. With ethylene glycol as the C-source, optimal conditions for the full nitrate removal by Arthrobacter were established under laboratory conditions with wastewaters from the synthesis of dinitroethylene glycol.
Research Interests:
Klebsiella oxytoca CECT 4460 removes high nitrate loads from industrial wastewaters without accumulation of nitrite under optimal culture conditions; however, under nonoptimal conditions nitrite accumulates. This situation reflects an in... more
Klebsiella oxytoca CECT 4460 removes high nitrate loads from industrial wastewaters without accumulation of nitrite under optimal culture conditions; however, under nonoptimal conditions nitrite accumulates. This situation reflects an in vivo-limited functioning of nitrite reductase in this strain. As a way to overcome this limitation, an increase in the nitrite reductase gene dose in K. oxytoca CECT 4460 was considered. To achieve this, we cloned and transferred into this strain the Klebsiella pneumoniae nasB gene, which encodes assimilatory nitrite reductase (Lin et al., J. Bacteriol. 176:2551-2559, 1994). The delivery vector was either the wide-host-range plasmid pUPE2, in which the nasB gene is expressed from the Escherichia coli Plac promoter, or a mini-Tn5-Km vector, which upon random insertion in the host chromosome allowed expression of the nasB gene from an unidentified chromosomal host promoter. The effect of the increase in the dose of the nasB gene in K. oxytoca CECT 446...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
In the last few years several investigations, based on culture-dependent and -independent techniques, have shown that salt-attacked stone surfaces present a habitat for extremely salt tolerant and moderate halophilic microorganisms. The... more
In the last few years several investigations, based on culture-dependent and -independent techniques, have shown that salt-attacked stone surfaces present a habitat for extremely salt tolerant and moderate halophilic microorganisms. The inner walls of the Chapel of St. Virgil in Vienna (Austria) are an example of this phenomenon. Salt crusts cover most of the wall surfaces and salt crystallization in the porous space of the stone is causing decohesion of material and destruction of the original medieval paintings. The salt, together with the oligotrophic conditions, creates a very special and extreme habitat for halotolerant and halophilic microorganisms.In this study we investigate and monitor the cultivable and non-cultivable members of the microbial community present on the stonework of the medieval Chapel of St. Virgil after several severe disturbances of the microbial environment caused by desalination and disinfection treatments. With this finality, a combination of culture-de...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests: Ancient History, Archaeology, Environmental microbiology, Spain, Biological Sciences, and 13 moreCave, Phylogeny, Environmental Sciences, Bacteria, Paintings, Phylogenetic Diversity, Bacterial Diversity, Ecosystem, Group, Genetic variation, Rhizobiaceae, Geologic Sediments, and Molecular Sequence Data
Research Interests:
The prosperity of Hallstatt (Salzkammergut region, Austria) is based on the richness of salt in the surrounding mountains and salt mining, which is documented as far back as 1500 years B.C. Substantial archaeological evidence of Bronze... more
The prosperity of Hallstatt (Salzkammergut region, Austria) is based on the richness of salt in the surrounding mountains and salt mining, which is documented as far back as 1500 years B.C. Substantial archaeological evidence of Bronze and Iron Age salt mining has been discovered, with a wooden staircase (1108 B.C.) being one of the most impressive and well preserved finds. However, after its discovery, fungal mycelia have been observed on the surface of the staircase, most probably due to airborne contamination after its find. As a basis for the further preservation of this valuable object, the active micro-flora was examined to investigate the presence of potentially biodegradative microorganisms. Most of the strains isolated from the staircase showed to be halotolerant and halophilic microorganisms, due to the saline environment of the mine. Results derived from culture-dependent assays revealed a high fungal diversity, including both halotolerant and halophilic fungi, the most d...