Search

Your search keyword '"Sedláček, Ivo"' showing total 280 results
Start Over Author "Sedláček, Ivo" Publication Year Range Last 50 years
280 results on '"Sedláček, Ivo"'

4. Corynebacterium mendelii sp. nov., a novel bacterium isolated from Adélie penguin oral cavity

Author

Koublová, Vendula, Sedlář, Karel, Sedláček, Ivo, Musilová, Jana, Staňková, Eva, Králová, Stanislava, Koudelková, Sylva, Krsek, Daniel, Švec, Pavel, Koublová, Vendula, Sedlář, Karel, Sedláček, Ivo, Musilová, Jana, Staňková, Eva, Králová, Stanislava, Koudelková, Sylva, Krsek, Daniel, and Švec, Pavel

Abstract

The taxonomic status of strain P5891T, isolated from an Adélie penguin beak swab, was investigated. Based on the 16S rRNA gene sequence, the strain was identified as a potentially novel Corynebacterium species, with the highest sequence similarities to Corynebacterium rouxii FRC0190T (96.7%) and Corynebacterium epidermidicanis DSM 45586T (96.6%). The average nucleotide identity values between strain P5891T and C. rouxii FRC0190T and C. epidermidicanis DSM 45586T were 68.2 and 69.2%, respectively. The digital DNA–DNA hybridization values between strain P5891T and C. rouxii FRC0190T and C. epidermidicanis DSM 45586T were 23.7 and 21.4%, respectively. Phylogenetic trees based on the 16S rRNA sequence placed strain P5891T in a separate branch with Corynebacterium canis 1170T and Corynebacterium freiburgense 1045T, while a phylogenomic tree based on the Corynebacterium species core genome placed the strain next to Corynebacterium choanae 200CHT. Extensive phenotyping and genomic analyses clearly confirmed that strain P5891T represents a novel species of the genus Corynebacterium, for which the name Corynebacterium mendelii sp. nov. is proposed, with the type strain P5891T (=CCM 8862T=LMG 31627T).

Published
2024

10. Staphylococcus brunensis sp. nov. isolated from human clinical specimens with a staphylococcal cassette chromosome-related genomic island outside of the rlmH gene bearing the ccrDE recombinase gene complex

Author

Kovařovic, Vojtěch, primary, Finstrlová, Adéla, additional, Sedláček, Ivo, additional, Petráš, Petr, additional, Švec, Pavel, additional, Mašlaňová, Ivana, additional, Neumann-Schaal, Meina, additional, Šedo, Ondrej, additional, Botka, Tibor, additional, Staňková, Eva, additional, Doškař, Jiří, additional, and Pantůček, Roman, additional

Published
2023
Full Text
View/download PDF

11. A Long-Term Study on the Bactericidal Effect of ZrN-Cu Nanostructured Coatings Deposited by an Industrial Physical Vapor Deposition System.

Author

Behrangi, Sahand, Staňková, Eva, Sedláček, Ivo, Šimoníková, Lucie, Souček, Pavel, Buršíková, Vilma, Sochora, Vjačeslav, Novotný, Karel, and Vašina, Petr

Subjects
PHYSICAL vapor deposition, SURFACE coatings, COPPER, ESCHERICHIA coli
Abstract

ZrN-Cu coatings containing two different amounts of Cu (~11 at.% and ~25 at.%) were deposited using an industrial physical vapor deposition (PVD) system. The as-deposited coatings exhibited 100% bactericidal efficiency against Escherichia coli CCM 3988 for an exposure time of 40 min. Subsequently, the samples were attached onto our faculty's door handles for six months to study the coatings' long-term effectiveness and durability under actual operational conditions. The samples were periodically evaluated and it was observed that the coatings with 25 at.% Cu performed better than the ones with 11 at.% Cu. For example, following 15 days of being touched, the bactericidal effectiveness of the sample containing 25 at.% Cu dropped to 65% while it fell to 42% for the sample containing 11 at.%. After 6 months, however, both samples showed bactericidal efficiency of ~16–20%. The bactericidal efficiency of the samples touched for 6 months was successfully restored by polishing them. Furthermore, a group of samples was kept untouched and was also evaluated. The untouched samples with Cu content of ~25 at.% did not show any drop in their bactericidal properties after 6 months. ZrN-Cu coatings were concluded to be promising materials for self-sanitizing application on high-touch surfaces. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

13. Pseudomonas petrae sp. nov. isolated from regolith samples in Antarctica

Author

Nováková, Dana, primary, Koublová, Vendula, additional, Sedlář, Karel, additional, Staňková, Eva, additional, Králová, Stanislava, additional, Švec, Pavel, additional, Neumann-Schaal, Meina, additional, Wolf, Jacqueline, additional, Koudelková, Sylva, additional, Barták, Miloš, additional, and Sedláček, Ivo, additional

Published
2023
Full Text
View/download PDF

14. Staphylococcus brunensis sp. nov. isolated from human clinical specimens with an SCC-related genomic island outside of the rlmH gene bearing ccrDE recombinase gene complex (LB068)

Author

Pantůček Roman, Kovařovic Vojtěch, Finstrlová Adéla, Sedláček Ivo, Petráš Petr, Mašlaňová Ivana, Švec Pavel, Neumann‐Schaa Meina, Šedo Ondrej, Botka Tibor, and Doškař Jiří

Subjects
Staphylococcus, coagulase-negative staphylococci, methicillin resistance, genomic islands, recombinase, SCC
Abstract

Background. Over the last three decades, coagulase-negative staphylococci (CoNS) have been recognised as opportunistic pathogens, especially in immunocompromised patients. CoNS serve as a reservoir of accessory genes, including virulence and antimicrobial resistance factors for the genus Staphylococcus. Recent diagnostic techniques allow recognising of novel CoNS species in human clinical specimens. Methods. Here, we characterised coagulase-negative staphylococcal strains from the Staphylococcus haemolyticus phylogenetic clade obtained from human ear swabs, wounds and bile. A polyphasic taxonomic approach based on whole genomic sequencing with expert annotation, extensive biotyping, DNA fingerprinting by rep-PCR, MALDI-TOF MS, and chemotaxonomy analyses was applied to establish their phylogenetic position and characterize virulence and drug-resistance genes. Results. Five isolates of Staphylococcus sp. were obtained from various human-related clinical specimens both from mixed culture and monoculture. Based on the polyphasic taxonomic approach, the novel species named Staphylococcus brunensis sp. nov. is proposed, with the closest relative Staphylococcus petrasii. The whole genome sequence analysis revealed the presence of several variable genomic elements including staphylococcal chromosomal cassette (SCC), prophages, genomic islands, various full and partial IS elements, and plasmids conferring beta-lactam and macrolide resistance. Three strains possess an 18.8 kb-long genomic island designated SbCIccr with a ccr gene complex designated ccrDE that had a conserved structure like a ccr gene complex from known SCC types. However, the SbCIccr was integrated into the serine acetyltransferase gene rimL, not into the canonical integration site for SCCs, methyltransferase gene rlmH (orfX). The genomic island harbours genes for the restriction-modification system commonly found on SCC elements, a putative transposon with IS6 family element similar to IS431mec, a putative transcriptional regulator and accessory genes, which have been found frequently on plasmids. By a PCR assay we showed that the SbCIccr could be mobilized from the bacterial chromosome. Conclusions. Study of SbCIccr has a crucial role in the understanding of the origin, evolution and transfer of SCC-like elements. It may also represent a primordial element able to accumulate virulence and drug resistance factors, whose spread into established pathogens such as S. aureus would be a threat to the healthcare system.

Published
2023

15. Corynebacterium antarcticum sp. nov., Corynebacterium marambiense sp. nov., Corynebacterium meridianum sp. nov., and Corynebacterium pygosceleis sp. nov., isolated from Adélie penguins (Pygoscelis adeliae)

Author

Švec, Pavel, primary, Busse, Hans-Jürgen, additional, Sedlář, Karel, additional, Musilová, Jana, additional, Králová, Stanislava, additional, Staňková, Eva, additional, Šedo, Ondrej, additional, Krsek, Daniel, additional, Koublová, Vendula, additional, Krištofová, Lucie, additional, and Sedláček, Ivo, additional

Published
2023
Full Text
View/download PDF

21. Characterisation of Waterborne Psychrophilic Massilia Isolates with Violacein Production and Description of Massilia antarctica sp. nov

Author

Sedláček, Ivo, Sedlář, Karel, Smolíková, Jana, Šedo, Ondrej, Pilný, Jan, Staňková, Eva, Sobotka, Roman, Švec, Pavel, Králová, Stanislava, Koublová, Vendula, Holochová, Pavla, and Busse, Hans-Jürgen

Subjects
Microbiology (medical), Emended Description, Lipid-Composition, Bacteria, Genome, Database, Soil, Gene, Classification, Degradation, Restriction, violacein, Massilia, whole-genome sequencing, Virology, description, Antarctica, psychrophilic, Microbiology
Abstract

A group of seven bacterial strains producing blue-purple pigmented colonies on R2A agar was isolated from freshwater samples collected in a deglaciated part of James Ross Island and Eagle Island, Antarctica, from 2017–2019. The isolates were psychrophilic, oligotrophic, resistant to chloramphenicol, and exhibited strong hydrolytic activities. To clarify the taxonomic position of these isolates, a polyphasic taxonomic approach was applied based on sequencing of the 16S rRNA, gyrB and lepA genes, whole-genome sequencing, rep-PCR, MALDI-TOF MS, chemotaxonomy analyses and biotyping. Phylogenetic analysis of the 16S rRNA gene sequences revealed that the entire group are representatives of the genus Massilia. The closest relatives of the reference strain P8398T were Massilia atriviolacea, Massilia violaceinigra, Massilia rubra, Massilia mucilaginosa, Massilia aquatica, Massilia frigida, Massilia glaciei and Massilia eurypsychrophila with a pairwise similarity of 98.6–100% in the 16S rRNA. The subsequent gyrB and lepA sequencing results showed the novelty of the analysed group, and the average nucleotide identity and digital DNA–DNA hybridisation values clearly proved that P8398T represents a distinct Massilia species. After all these results, we nominate a new species with the proposed name Massilia antarctica sp. nov. The type strain is P8398T (= CCM 8941T = LMG 32108T).

Published
2022
Full Text
View/download PDF

22. Staphylococcus ratti sp. nov. Isolated from a Lab Rat

Author

Kovařovic, Vojtěch, primary, Sedláček, Ivo, additional, Petráš, Petr, additional, Králová, Stanislava, additional, Mašlaňová, Ivana, additional, Švec, Pavel, additional, Neumann-Schaal, Meina, additional, Botka, Tibor, additional, Gelbíčová, Tereza, additional, Staňková, Eva, additional, Doškař, Jiří, additional, and Pantůček, Roman, additional

Published
2022
Full Text
View/download PDF

31. Classification of a Violacein-Producing Psychrophilic Group of Isolates Associated with Freshwater in Antarctica and Description of Rugamonas violacea sp. nov.

Author

Sedláček, Ivo, primary, Holochová, Pavla, additional, Sobotka, Roman, additional, Busse, Hans-Jürgen, additional, Švec, Pavel, additional, Králová, Stanislava, additional, Šedo, Ondrej, additional, Pilný, Jan, additional, Staňková, Eva, additional, Koublová, Vendula, additional, and Sedlář, Karel, additional

Published
2021
Full Text
View/download PDF

37. Classification of a Violacein-Producing Psychrophilic Group of Isolates Associated with Freshwater in Antarctica and Description of Rugamonas violacea sp. nov.

Author

Sedláček, Ivo, Holochová, Pavla, Sobotka, Roman, Busse, Hans-Jürgen, Švec, Pavel, Králová, Stanislava, Šedo, Ondrej, Pilný, Jan, Staňková, Eva, Koublová, Vendula, Sedlář, Karel, Sedláček, Ivo, Holochová, Pavla, Sobotka, Roman, Busse, Hans-Jürgen, Švec, Pavel, Králová, Stanislava, Šedo, Ondrej, Pilný, Jan, Staňková, Eva, Koublová, Vendula, and Sedlář, Karel

Abstract

A group of 11 bacterial strains was isolated from streams and lakes located in a deglaciated northern part of James Ross Island, Antarctica. They were rod-shaped, Gram-stain-negative, motile, and catalase-positive and produced blue-violet-pigmented colonies on R2A agar. A polyphasic taxonomic approach based on 16S rRNA gene sequencing, whole-genome sequencing, automated ribotyping, repetitive element sequence-based PCR (rep-PCR), MALDI-TOF MS, fatty acid profile, chemotaxonomy analyses, and extensive biotyping was applied in order to clarify the taxonomic position of these isolates. Phylogenetic analysis based on the 16S rRNA gene indicated that all the isolates constituted a coherent group belonging to the genus Rugamonas. The closest relatives to the representative isolate P5900T were Rugamonas rubra CCM 3730T, Rugamonas rivuli FT103WT, and Rugamonas aquatica FT29WT, exhibiting 99.2%, 99.1%, and 98.6% 16S rRNA pairwise similarity, respectively. The average nucleotide identity and digital DNA-DNA hybridization values calculated from the whole-genome sequencing data clearly proved that P5900T represents a distinct Rugamonas species. The G+C content of genomic DNAs was 66.1mol%. The major components in fatty acid profiles were summed feature 3 (C16:1 7c/C16:1 6c), C 16:0, and C12:0. The cellular quinone content contained exclusively ubiquinone Q-8. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The polyamine pattern was composed of putrescine, 2-hydroxputrescine, and spermidine.

Published
2021

38. Flavobacterium flabelliforme sp. nov. and Flavobacterium geliluteum sp. nov., two multidrug-resistant psychrotrophic species isolated from Antarctica

Author

Králová, Stanislava, Busse, Hans-Jürgen, Bezdíček, Matěj, Sandoval-Powers, Megan, Nykrýnová, Markéta, Staňková, Eva, Krsek, Daniel, Sedláček, Ivo, Králová, Stanislava, Busse, Hans-Jürgen, Bezdíček, Matěj, Sandoval-Powers, Megan, Nykrýnová, Markéta, Staňková, Eva, Krsek, Daniel, and Sedláček, Ivo

Abstract

Despite unfavourable Antarctic conditions, such as cold temperatures, freeze-thaw cycles, high ultraviolet radiation, dryness and lack of nutrients, microorganisms were able to adapt and surprisingly thrive in this environment. In this study, eight cold-adapted Flavobacterium strains isolated from a remote Antarctic island, James Ross Island, were studied using polyphasic taxonomic approach to determine their taxonomic position. Phylogenomic analyses based on 16S rRNA gene and 92 core genes clearly showed that these strains formed two distinct phylogenetic clusters comprising three and five strains, with average nucleotide identities significantly below 90 % in between both proposed species as well as between their closest phylogenetic relatives. Phenotyping revealed a unique pattern of biochemical and physiological characteristics enabling differentiation from the closest phylogenetically related Flavobacterium spp. Chemotaxonomic analyses showed that type strains P4023T and P7388T were characterized by the major polyamine sym-homospermidine and a quinone system containing predominantly menaquinone MK-6. In the polar lipid profile phosphatidylethanolamine, an ornithine lipid and two unidentified lipids lacking a functional group were detected as major lipids. These characteristics along with fatty acid profiles confirmed, that these species belong to the genus Flavobacterium. Thorough genomic analysis revealed presence of numerous cold-inducible or cold-adaptation associated genes, such as cold-shock proteins, proteorhodopsin, carotenoid biosynthetic genes or oxidative-stress response genes. Genomes of type strains surprisingly harboured multiple prophages, with many of them predicted to be active. Genome-mining identified biosynthetic clusters in type strain genomes with majority not matching any known biosynthetic genes which indicates further research possibilities involving these psychrotrophic bacteria. Antibiotic susceptibility testing revealed multidrug-resi

Published
2021

44. Description of Massilia rubra sp. nov., Massilia aquatica sp. nov., Massilia mucilaginosa sp. nov., Massilia frigida sp. nov., and one Massilia genomospecies isolated from Antarctic streams, lakes and regoliths

Author

Holochová, Pavla, primary, Mašlaňová, Ivana, additional, Sedláček, Ivo, additional, Švec, Pavel, additional, Králová, Stanislava, additional, Kovařovic, Vojtěch, additional, Busse, Hans-Jürgen, additional, Staňková, Eva, additional, Barták, Miloš, additional, and Pantůček, Roman, additional

Published
2020
Full Text
View/download PDF

47. The influence of soil environment on the degradation of archaeological leather.

Author

Vyskočilová, Gabriela, Kopecká, Radka, Pavliňák, David, Laichmanová, Monika, Sedláček, Ivo, Orlita, Alois, Příhoda, Jiří, and Miu, Lucretia

Subjects
SOIL degradation, ENVIRONMENTAL soil science, LEATHER, ARCHAEOLOGICAL excavations, ARCHAEOLOGICAL finds, SOIL composition, ARCHAEOLOGICAL geology
Abstract

Leather objects, found in archaeological excavations, survive in a specific environment. This leather material is very delicate and only little is known about the mechanism of its (bio)degradation in a soil environment. The main goal of this study was to clarify how leather is affected by a soil environment and why archaeological leathers have their typical properties. We tested the influence of the soil (bio)degradation processes on the mechanical properties, colour difference, morphological changes, possible absorption of additional inorganic components from soil and changes of the leather composition. The microbial activity of the soil was also analysed. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

48. Pyocin‐mediated antagonistic interactions in Pseudomonas spp. isolated in James Ross Island, Antarctica.

Author

Snopková, Kateřina, Dufková, Kristýna, Chamrád, Ivo, Lenobel, René, Čejková, Darina, Kosina, Marcel, Hrala, Matěj, Holá, Veronika, Sedláček, Ivo, and Šmajs, David

Subjects
SOIL microbiology, BACTERIAL communities, GENE clusters, PSEUDOMONAS, ANTI-infective agents, ISLANDS, TRICHODERMA
Abstract

Summary: Interactions within bacterial communities are frequently mediated by the production of antimicrobial agents. Despite the increasing interest in research of new antimicrobials, studies describing antagonistic interactions among cold‐adapted microorganisms are still rare. Our study assessed the antimicrobial interactions of 36 Antarctic Pseudomonas spp. and described the genetic background of these interactions in selected strains. The overall bacteriocinogeny was greater compared to mesophilic Pseudomonas non‐aeruginosa species. R‐type tailocins were detected on transmission electron micrographs in 16 strains (44.4%); phylogenetic analysis of the corresponding gene clusters revealed that the P. prosekii CCM 8878 tailocin was related to the Rp3 group, whereas the tailocin in Pseudomonas sp. CCM 8880 to the Rp4 group. Soluble antimicrobials were produced by eight strains (22.‐2%); gene mining found pyocin L homologues in the genomes of P. prosekii CCM 8881 and CCM 8879 and pyocin S9‐like homologues in P. prosekii CCM 8881 and Pseudomonas sp. CCM 8880. Analysis of secretomes confirmed the production of all S‐ and L‐type pyocin genes. Our results suggest that bacteriocin‐based inhibition plays an important role in interactions among Antarctic soil bacteria, and these native, cold‐adapted microorganisms could be a promising source of new antimicrobials. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results