Brown mud, as a waste product of the industrial process of aluminum production, represents a great environmental burden due to its toxicity to living organisms. However, some microorganisms are able to survive in this habitat, and they can be used in bioremediation processes. Traditional cultivation methods have a limited capacity to characterize bacterial composition in environmental samples. Recently, next-generation sequencing methods have provided new perspectives on microbial community studies. The aim of this study was to analyze the bacterial community in the drainage water of brown mud disposal site near Žiar nad Hronom (Banská Bystrica region, Slovakia) using 454 pyrosequencing. We obtained 9964 sequences assigned to 163 operational taxonomic units belonging to 10 bacterial phyla. The phylum Proteobacteria showed the highest abundance (80.39%) within the bacterial community, followed by Firmicutes (13.05%) and Bacteroidetes (5.64%). Other bacterial phyla showed an abundance lower than 1%. The classification yielded 85 genera. Sulfurospirillum spp. (45.19%) dominated the bacterial population, followed by Pseudomonas spp. (13.76%) and Exiguobacterium spp. (13.02%). These results indicate that high heavy metals content, high pH, and lack of essential nutrients are the drivers of a dramatic reduction of diversity in the bacterial population in this environment.

• MeSH
• Bacteria klasifikace   genetika   izolace a purifikace   MeSH
• biodegradace MeSH
• biodiverzita * MeSH
• chemické látky znečišťující vodu analýza   metabolismus   MeSH
• fylogeneze MeSH
• fyziologie bakterií * MeSH
• hutnictví MeSH
• koncentrace vodíkových iontů MeSH
• mikrobiální společenstva genetika   MeSH
• odpadní voda chemie   mikrobiologie   MeSH
• RNA ribozomální 16S genetika   MeSH
• sekvenční analýza DNA MeSH
• těžké kovy analýza   metabolismus   MeSH
• vysoce účinné nukleotidové sekvenování * MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Slovenská republika MeSH

Nowadays, Varroa destructor is considered as a serious pest of honeybees (Apis mellifera) and its resistance to acaricides has been reported in Europe since the early 1990s. That is why new methods of treatment for Varroa mites are still in focus of many scientists. In our study, we determined the lethal concentration LC50 (72 h) of 2.425% oxalic acid solution following single spray exposure of honeybee larvae under laboratory conditions (Guideline OECD 237 2013). Potential sublethal effects of oxalic acid were monitored through the determination of the activity of antioxidant enzymes. Activation of primary antioxidant enzymes was observed at 1.75% of oxalic acid; 3.5% of oxalic acid brought on a statistically significant increase of glutathione S-transferase activity. This change was accompanied by an increase in thiobarbituric acid reactive substances, products of lipid peroxidation. Our results indicate that oxalic acid may be harmful to bee brood when present during application.

• MeSH
• akaricidy toxicita   MeSH
• antioxidancia metabolismus   MeSH
• kyselina oxalová toxicita   MeSH
• larva účinky léků   MeSH
• LD50 MeSH
• Varroidae MeSH
• včely účinky léků   enzymologie   růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• Publikační typ
• abstrakt z konference MeSH

• MeSH
• anaerobióza MeSH
• mikrobiologie MeSH
• výzkum MeSH
• Publikační typ
• úvodní články MeSH
• Geografické názvy
• Slovenská republika MeSH

• MeSH
• anaerobní bakterie MeSH
• kongresy jako téma MeSH

Complete 16S rRNA sequences were determined of recently proposed new species of treponemes designated strain S and T. Sequence comparison indicated that both species belong to the Treponema saccharophilum cluster, having thus at least 5 cultivable representatives. Phylogenetic analysis of available GenBank 16S rRNA sequences revealed two phylogenetically distant treponema clusters (T. saccharophilum cluster and T. bryantii cluster). Surprisingly, while among cultivated treponemes dominate T. saccharophilum cluster members, detailed analysis showed that all treponema-like sequences obtained by culture independent 16S rRNA methods belong to the T. bryantii cluster, from which only two cultivable representatives have so far been known. Meta-analysis of available data revealed that treponemes are an infrequent and minor group of bacteria, representing less than 2.4% of total rumen bacteria.

• MeSH
• bachor mikrobiologie   MeSH
• DNA bakterií genetika   chemie   MeSH
• financování organizované MeSH
• fylogeneze MeSH
• molekulární sekvence - údaje MeSH
• počet mikrobiálních kolonií MeSH
• přežvýkavci mikrobiologie   MeSH
• ribozomální DNA genetika   chemie   MeSH
• RNA ribozomální 16S genetika   MeSH
• sekvenční analýza DNA MeSH
• shluková analýza MeSH
• Treponema izolace a purifikace   klasifikace   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

Rumen bacterium Pseudobutyrivibrio ruminis strain k3 utilized over 90% sucrose added to the growth medium as a sole carbon source. Zymographic studies of the bacterial cell extract revealed the presence of a single enzyme involved in sucrose digestion. Thin layer chromatography showed fructose and glucose-1-phosphate (Glc1P) as end products of the digestion of sucrose by identified enzyme. The activity of the enzyme depended on the presence of inorganic phosphate and was the highest at the concentration of phosphate 56 mmol/L. The enzyme was identified as the sucrose phosphorylase (EC 2.4.1.7) of molar mass approximately 54 kDa and maximum activity at pH 6.0 and 45 degrees C. The calculated Michaelis constant (Km) for Glc1P formation and release of fructose by partially purified enzyme were 4.4 and 8.56 mmol/L while the maximum velocities of the reaction (Vlim) were 1.19 and 0.64 micromol/L per mg protein per min, respectively.

• MeSH
• bachor mikrobiologie   MeSH
• bakteriální proteiny chemie   izolace a purifikace   metabolismus   MeSH
• chromatografie na tenké vrstvě MeSH
• fosfáty metabolismus   MeSH
• fruktosa metabolismus   MeSH
• glukosafosfáty metabolismus   MeSH
• glukosyltransferasy chemie   izolace a purifikace   metabolismus   MeSH
• grampozitivní bakterie izolace a purifikace   metabolismus   MeSH
• kinetika MeSH
• koncentrace vodíkových iontů MeSH
• kultivační média chemie   MeSH
• molekulová hmotnost MeSH
• sacharosa metabolismus   MeSH
• stabilita enzymů MeSH
• uhlík metabolismus   MeSH
• vnímání teploty MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

The inter- and intraspecies variability of lactate dehydrogenase (ldh) gene was determined among the predominant ruminal lactate utilizing bacteria. Nearly complete nucleotide sequences of ldh gene, encoding NAD-dependent lactate dehydrogenase of three Megasphaera elsdenii and six Selenomonas ruminantium strains, were obtained and compared. Phylogenetic analyses revealed a limited variability between the ldh sequences studied. The majority of differences observed were silent mutations at the 3rd position of codons. Surprisingly, the intraspecies diversity of the ldh gene among S. ruminantium isolates was higher than the interspecies level between S. ruminantium and M. elsdenii, which strongly suggests the possibility of acquisition of this gene by horizontal gene transfer.

• MeSH
• acidóza laktátová metabolismus   MeSH
• bachor mikrobiologie   MeSH
• bakteriální proteiny genetika   MeSH
• bodová mutace MeSH
• DNA bakterií genetika   chemie   MeSH
• fylogeneze MeSH
• genetická variace MeSH
• L-laktátdehydrogenasa genetika   MeSH
• Megasphaera MeSH
• molekulární sekvence - údaje MeSH
• sekvenční analýza DNA MeSH
• sekvenční homologie MeSH
• Selenomonas MeSH
• shluková analýza MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

P. ruminis strain 3 was isolated from the ovine rumen and identified on the basis of comparison of its 16S rRNA gene with GenBank. The bacterium was able to grow on Timothy grass fructan, inulin, sucrose, fructose and glucose as a sole carbon source, reaching absorbance of population in a range of 0.4-1.2. During 1 d the bacteria exhausted 92-97% of initial dose of saccharides except for inulin (its utilization did not exceed 33%). The bacterial cell extract catalyzed the degradation of Timothy grass fructan, inulin and sucrose in relation to carbon source present in growth medium. Molecular filtration on Sephadex G-150, polyacrylamide gel electrophoresis combined with zymography technique and TLC was used to identify enzymes responsible for the digestion of sucrose and both polymers of fructose. Two specific endolevanases (EC 3.2.1.65), nonspecific beta-fructofuranosidase (EC 3.2.1.80 and/or EC 3.2.1.26) and sucrose phosphorylase (EC 2.4.1.7) were detected in cell-free extract from bacteria grown on Timothy grass fructan.

• MeSH
• bachor mikrobiologie   MeSH
• bakteriální proteiny izolace a purifikace   metabolismus   MeSH
• chromatografie MeSH
• DNA bakterií genetika   chemie   MeSH
• enzymy izolace a purifikace   metabolismus   MeSH
• financování organizované MeSH
• fruktany metabolismus   MeSH
• fylogeneze MeSH
• grampozitivní bakterie MeSH
• inulin metabolismus   MeSH
• molekulární sekvence - údaje MeSH
• Phleum chemie   MeSH
• ribozomální DNA genetika   chemie   MeSH
• RNA ribozomální 16S genetika   MeSH
• sacharosa metabolismus   MeSH
• sekvenční analýza DNA MeSH
• shluková analýza MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH