Technosols are artificial soils generated by diverse human activities and frequently contain toxic substances resulting from industrial processes. Due to lack of nutrients and extreme physico-chemical properties, they represent environments with limited bacterial colonization. Bacterial populations of technosols are dominated usually by Actinobacteria, including streptomycetes, known as a tremendous source of biotechnologically important molecules. In this study, the biodiversity of streptomycete-like isolates from several technosols, mainly mine soils and wastes (landfills and sludge) in Slovakia, was investigated. The combination of basic morphological and biochemical characterisations, including heavy metal resistance determination, and molecular approaches based on 16S rRNA gene analysis were used for the identification of the bacterial strains. From nine isolates of Actinobacteria collected from different habitats, one was found to represent a new species within the Crossiella genus. Eight other isolates were assigned to the genus Streptomyces, of which at least one could represent a new bacterial species. Some isolates showed high resistance to Pb, Zn, Cu or Ni. The most tolerated metal was Pb. The results obtained in this study indicate that technosols are a prospective source of new actinomycete species resistant to heavy metals what underlines their bioremediation potential.

During studies on fructan degradation in the rumen, a Treponema-like bacterium able to utilize Timothy grass fructan, commercial inulin and sucrose a

This study investigated the genetic variability and antibiotic resistance of Acinetobacter community depending on the stage of wastewater treatment in Kokšov-Bakša for the city of Košice (Slovakia). After cultivation, bacterial isolates were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and their sensitivity to ampicillin, kanamycin, tetracycline, chloramphenicol and ciprofloxacin was examined. Acinetobacter spp. and Aeromonas spp. dominated bacterial populations in all wastewater samples. We identified 12 different groups based on protein profiling, 14 genotypes by amplified ribosomal DNA restriction analysis and 11 Acinetobacter species using 16S rDNA sequence analysis within Acinetobacter community, which showed significant variability in their spatial distribution. While Acinetobacter population structure changed during the wastewater treatment, the prevalence of antibiotic-resistant strains did not significantly vary depending on the stage of wastewater treatment. The study highlights the role of a highly genetically diverse Acinetobacter community surviving in wastewater treatment plants as an important environmental reservoir assisting in the further dissemination of antibiotic resistance in aquatic systems.

Since the beginning of unicellular life, dissimilation reactions of autotrophic sulfur bacteria have been a crucial part of the biogeochemical sulfur cycle on Earth. A wide range of sulfur oxidation states is reflected in the diversity of metabolic pathways used by sulfur-oxidizing bacteria. This metabolically and phylogenetically diverse group of microorganisms inhabits a variety of environments, including extreme environments. Although they have been of interest to microbiologists for more than 150 years, meso- and psychrophilic chemolithoautotrophic sulfur-oxidizing microbiota are less studied compared to the microbiota of hot springs. Several recent studies suggested that cold sulfur waters harbor unique, yet not described, bacterial taxa.