Alkaline Technosol contaminated by former mining activity and its culturable autochthonous microbiota.

Technosols or technogenic substrates contaminated by potentially toxic elements as a result of iron mining causes not only contamination of the surrounding ecosystem but may also lead to changes of the extent, abundance, structure and activity of soil microbial community. Microbial biomass were significantly inhibited mainly by exceeding limits of potentially toxic metals as arsenic (in the range of 343-511 mg/kg), copper (in the range of 7980-9227 mg/kg), manganese (in the range of 2417-2670 mg/kg), alkaline and strong alkaline pH conditions and minimal contents of organic nutrients. All of the 14 bacterial isolates, belonged to 4 bacterial phyla, Actinobacteria, Firmicutes; ß- and γ-Proteobacteria. Thirteen genera and 20 species of microscopic filamentous fungi were recovered. The most frequently found species belonged to genera Aspergillus (A. clavatus, A. niger, A. flavus, A. versicolor, Aspergillus sp.) with the dominating A. niger in all samples, and Penicillium (P. canescens, P. chrysogenum, P. spinulosum, Penicillium sp.). Fungal plant pathogens occurred in all surface samples. These included Bjerkandera adustata, Bionectria ochloleuca with anamorph state Clonostachys pseudochloleuca, Lewia infectoria, Phoma macrostoma and Rhizoctonia sp.

Halophilic bacteria are colonizing the exhibition areas of the Capuchin Catacombs in Palermo, Italy.

The Capuchin Catacombs of Palermo, Italy, contain over 1800 mummies dating from the 16th to 20th centuries AD. Their environment is not conducive to the conservation of the remains due to, among other factors, water infiltration, which is producing salt efflorescences on the walls. A multiphasic approach was applied to investigate the halophilic microbiota present in the Catacombs. Enrichment cultures were conducted on media containing different NaCl concentrations, ranging from 3 to 20 %. For screening of the strains, the following two PCR-based methods were used and compared: fluorescence internal transcribed spacer PCR (f-ITS) and random amplification of polymorphic DNA (RAPD) analyses. Results derived from RAPD profiles were shown to be slightly more discriminative than those derived from f-ITS. In addition, the proteolytic and cellulolytic abilities were screened through the use of plate assays, gelatin agar and Ostazin Brilliant Red H-3B (OBR-HEC), respectively. Many of the strains isolated from the wall samples displayed proteolytic activities, such as all strains belonging to the genera Bacillus, Virgibacillus and Arthrobacter, as well as some strains related to the genera Oceanobacillus, Halobacillus and Idiomarina. In addition, many of the strains isolated from materials employed to stuff the mummies showed cellulolytic activities, such as those related to species of the genera Chromohalobacter and Nesterenkonia, as well as those identified as Staphylococcus equorum and Halomonas sp. Furthermore, many of the strains were pigmented ranging from yellow to a strong pink color, being directly related to the discoloration displayed by the materials.

A novel PCR-based approach for the detection and classification of potential cellulolytic fungal strains isolated from museum items and surrounding indoor environment.

AIMS: To develop a novel PCR-based method able to detect potential cellulolytic filamentous fungi and to classify them exploiting the amplification of the cellobiohydrolase gene (cbh-I) and its polymorphism. METHODS AND RESULTS: A mixed approach including the combination of (i) fungal cultivation and isolation, (ii) classification of fungal isolates through the amplification of the cbh gene using a fluorescently labelled primer (f-CBH-PCR) and (iii) final fungal identification based on amplification and sequencing of the ITS1-5.8S rDNA-ITS2 region of the selected fungal strains was developed. By this approach, it was possible to screen 77 fungal strains belonging to 14 genera and 26 species. CONCLUSIONS: The f-CBH-PCR permitted the discrimination of fungal species, producing typical f-CBH profiles. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, the cbh gene was used as a preliminary classification tool able to differentiate among themselves the fungal members isolated from indoor museum items and surrounding environment. Such mixed approach consented the fast identification of all isolated fungal strains. The f-CBH-PCR method demonstrated its discrimination power, and it can be considered as a new molecular system suitable for the classification of fungal strains isolated from different environments.

Selection and identification of autochthonous yeasts in Slovakian wine samples using a rapid and reliable three-step approach.

AIMS: The investigation of yeast microflora during the must fermentation of two wine varieties (Frankovka modra - Blaufränkisch and Veltlinske zelene - Grüner Veltliner) from two consecutive vintages was performed using a three-step approach. METHODS AND RESULTS: The investigation strategy consisted of the combination of yeast cultivation, selection of the isolated yeasts based on the amplification of internal transcribed spacer 2 using a fluorescence-labelled primer (f-ITS-PCR) and a final identification step based on amplification and sequencing of the ITS1-5.8S rDNA-ITS2 region of the selected yeasts. By this three-step approach, it was possible to screen 433 yeasts isolates that belonged to 13 different species. CONCLUSIONS: The f-ITS-PCR allowed the unambiguous differentiation of all isolated yeast species that produced their typical f-ITS-PCR profile. SIGNIFICANCE AND IMPACT OF THE STUDY: This is one of few reports that treat the yeast diversity in Slovakian wines and in two varieties largely cultivated in Central Europe. The three-step approach permitted the rapid and reliable identification of isolated yeasts. The f-ITS-PCR with its good discrimination power can represent a suitable molecular tool for the selection of yeast members recovered from food or other environments.