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Peter Pristaš - One of the best experts on this subject based on the ideXlab platform.
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Variability of putative rep gene cassettes in Selenomonas ruminantium plasmids.
FEMS microbiology letters, 2012Co-Authors: L. Fecskeová, Peter Javorsky, Jozef Ivan, Peter PristašAbstract:Characteristic feature of the most of Selenomonas ruminantium cryptic plasmids is the presence of short, conserved sequences encompassing the gene for replication protein creating a potential rep gene cassette. PCR-based experiment was designed to analyse the genetic organization of putative plasmid rep modules and to assess S. ruminantium plasmid biodiversity. Analysed PCR amplicons contained single open reading frames encoding for putative replication proteins. While most of the derived protein sequences were often found to be conserved among putative plasmid molecules, at noncoding regions, genetic variability was observed to various extents. Complete nucleotide sequence of a plasmid was determined that contained probably a new rep gene only distantly related to known Selenomonas Rep proteins but at noncoding regions shared high homology with already known plasmids. Our results document considerable structural instability and sequence variability of analysed rep gene cassettes and suggest a modular structure of S. ruminantium plasmids potentially accessible for rep gene module exchanges.
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spreading and mutability of Selenomonas ruminantium plasmids
Folia Microbiologica, 2006Co-Authors: Jozef Ivan, P Javorský, A Sprincova, Peter PristašAbstract:Two small plasmids fromSelenomonas ruminantium strain 19D were cloned inEscherichia coli and completely characterized. Sequence comparison indicated that the plasmids are similar to those reported in genetically vaguely relatedS. ruminantium strain S20. Small 1.4-kb plasmids pSRD191 and pONE430 are only distantly related (≈30 % for deduced Rep protein amino acid sequence) but possess a short highly conserved region outsiderep gene. Larger plasmids pSRD192 and pONE429 possess large identical DNA regions in an otherwise dissimilar background. Recombination is proposed as an important mechanism of evolution and spreading ofS. ruminantium plasmids.
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pSRD191, a new member of RepL replicating plasmid family from Selenomonas ruminantium.
Plasmid, 2005Co-Authors: Adriana Sprincova, Peter Javorsky, Peter PristašAbstract:Abstract A numerous plasmid population was detected in strain 19 of Selenomonas ruminantium . The population was found to consist of six plasmids in size ranging from 1.4 to more than 20 kb. The smallest 1.4 kb cryptic plasmid pSRD191 was further characterized. Sequence analysis identified a single ORF encoding the 177-residue putative replication protein (Rep191) which shared significant homology with RepL family of replication protein from Firmicutes ( staphylococci and bacilli ). PCR analysis and Southern hybridisation showed that pSRD191 related plasmids are frequently encountered in rumen selenomonads.
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diversity of dna sequences among restriction endonucleases producing Selenomonas ruminantium isolates detected by enterobacterial repetitive intergenic consensus based polymerase chain reaction eric pcr
Anaerobe, 2000Co-Authors: Boris Zatkovic, Peter Javorsky, Veronika Molnarova, Vladimir Kmet, Peter PristašAbstract:Abstract Enterobacterial repetitive intergenic consensus-based polymerase chain reaction (ERIC-PCR) was found useful for discrimination of rumen selenomonads. Simultaneous use of ERICIR and ERIC2 primers yielded strain-specific banding patterns. The patterns were compared using Dice similarity coefficients and a DNA relatedness dendrogram based on the unweighted pair group method using arithmetic averages (UPGMA) was constructed. Five clusters and four single strains were identified at a similarity level of 50%. Very weak grouping was observed for lactilytica and ruminantium subspecies of Selenomonas ruminantium , indicating that lactate utilization has probably no taxonomic value. Restriction and modification phenotypes are weakly reflected in the dendrogram probably as the result of horizontal genetic transfer of genes encoding these phenotypic traits. While diverse in ERIC-PCR analysis, strains shown little variation in restriction fragment length polymorphism of amplified 16S-rRNA genes. All but one strain produced nearly identical profile indicating that majority of DNA diversity observed is due to epigenetic factors and not due to evolutionary divergence.
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Isolation and characterization of a new restriction endonuclease, Sru30DI, from Selenomonas ruminantium.
Gene, 1995Co-Authors: Peter Pristaš, Ivan Vanat, Peter JavorskyAbstract:Abstract The restriction endonuclease (ENase) Sru 30DI, an isoschizomer of Stu I, which recognizes the sequence 5′-AGG/ CCT-3′, was purified from a natural isolate of Selenomonas ruminantium . The ENase was isolated from cell extracts using single-step purification by phosphocellulose column chromatography. Activity of Sru 30DI is inhibited by overlapping Dcm methylation. The ENase is extremely stable at 37°C and is active over a wide range of pH, temperature and salt concentrations.
Dagmar Matoulková - One of the best experts on this subject based on the ideXlab platform.
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Development of a PCR assay based on the 16S–23S rDNA internal transcribed spacer for identification of strictly anaerobic bacterium Zymophilus
Anaerobe, 2015Co-Authors: Jürgen Felsberg, Markéta Jelínková, P. Kubizniaková, Dagmar MatoulkováAbstract:Abstract PCR-primers were designed for identification of strictly anaerobic bacteria of the genus Zymophilus based on genus-specific sequences of the 16S–23S rDNA internal transcribed spacer region. The specificity of the primers was tested against 37 brewery-related non-target microorganisms that could potentially occur in the same brewery specimens. None DNA was amplified from any of the non-Zymophilus strains tested including genera from the same family (Pectinatus, Megasphaera, Selenomonas), showing thus 100% specificity. PCR assay developed in this study allows an extension of the spectra of detected beer spoilage microorganisms in brewery laboratories.
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Development of a species-specific PCR assay for identification of the strictly anaerobic bacterium Selenomonas lacticifex found in biofilm-covered surfaces in brewery bottling halls.
Journal of applied microbiology, 2014Co-Authors: Jürgen Felsberg, Markéta Jelínková, P. Kubizniaková, Dagmar MatoulkováAbstract:Aims In recent years, beer-spoilage cases from strictly anaerobic bacteria have risen in frequency, in connection with the production of non-pasteurized, non-alcohol and low-alcoholic beers and with the lowering of dissolved oxygen in the packaged beer. Selenomonas lacticifex, found in brewer's yeast and in biofilms covering some surfaces in brewery bottling area, is considered to be a beer-spoilage organism. This study aims to develop S. lacticifex-specific PCR assay. The objective of this study was also evaluation of the specificity and reproducibility of the developed PCR assay in real brewery samples. Methods and Results Three primers (one forward and two reverse) were designed for identification of the strictly anaerobic bacterium S. lacticifex on the basis of the species-specific sequences of the 16S rDNA region. The specificity of the primers was tested against 44 brewery-related non-target micro-organisms that could potentially occur in the same brewery specimens. None of the primer pairs amplified DNA from any of the non-S. lacticifex strains tested including genera from the same family (Pectinatus, Megasphaera, Zymophilus) and the closely related species Selenomonas ruminantium, showing thus 100% specificity. Conclusions The PCR assay developed in this study enables the detection of the strictly anaerobic bacterium S. lacticifex in real brewery samples including pitching yeast. Significance and Impact of the Study Selenomonas lacticifex-specific PCR assay developed in this study allows for the extension of the spectra of detected beer-spoilage micro-organisms in brewing laboratories and thus lowering the risk of contamination of the final product.
Jürgen Felsberg - One of the best experts on this subject based on the ideXlab platform.
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Development of a PCR assay based on the 16S–23S rDNA internal transcribed spacer for identification of strictly anaerobic bacterium Zymophilus
Anaerobe, 2015Co-Authors: Jürgen Felsberg, Markéta Jelínková, P. Kubizniaková, Dagmar MatoulkováAbstract:Abstract PCR-primers were designed for identification of strictly anaerobic bacteria of the genus Zymophilus based on genus-specific sequences of the 16S–23S rDNA internal transcribed spacer region. The specificity of the primers was tested against 37 brewery-related non-target microorganisms that could potentially occur in the same brewery specimens. None DNA was amplified from any of the non-Zymophilus strains tested including genera from the same family (Pectinatus, Megasphaera, Selenomonas), showing thus 100% specificity. PCR assay developed in this study allows an extension of the spectra of detected beer spoilage microorganisms in brewery laboratories.
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Development of a species-specific PCR assay for identification of the strictly anaerobic bacterium Selenomonas lacticifex found in biofilm-covered surfaces in brewery bottling halls.
Journal of applied microbiology, 2014Co-Authors: Jürgen Felsberg, Markéta Jelínková, P. Kubizniaková, Dagmar MatoulkováAbstract:Aims In recent years, beer-spoilage cases from strictly anaerobic bacteria have risen in frequency, in connection with the production of non-pasteurized, non-alcohol and low-alcoholic beers and with the lowering of dissolved oxygen in the packaged beer. Selenomonas lacticifex, found in brewer's yeast and in biofilms covering some surfaces in brewery bottling area, is considered to be a beer-spoilage organism. This study aims to develop S. lacticifex-specific PCR assay. The objective of this study was also evaluation of the specificity and reproducibility of the developed PCR assay in real brewery samples. Methods and Results Three primers (one forward and two reverse) were designed for identification of the strictly anaerobic bacterium S. lacticifex on the basis of the species-specific sequences of the 16S rDNA region. The specificity of the primers was tested against 44 brewery-related non-target micro-organisms that could potentially occur in the same brewery specimens. None of the primer pairs amplified DNA from any of the non-S. lacticifex strains tested including genera from the same family (Pectinatus, Megasphaera, Zymophilus) and the closely related species Selenomonas ruminantium, showing thus 100% specificity. Conclusions The PCR assay developed in this study enables the detection of the strictly anaerobic bacterium S. lacticifex in real brewery samples including pitching yeast. Significance and Impact of the Study Selenomonas lacticifex-specific PCR assay developed in this study allows for the extension of the spectra of detected beer-spoilage micro-organisms in brewing laboratories and thus lowering the risk of contamination of the final product.
Xiuzhu Dong - One of the best experts on this subject based on the ideXlab platform.
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Selenomonas bovis sp. nov., isolated from yak rumen contents.
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY, 2009Co-Authors: Kegui Zhang, Xiuzhu DongAbstract:Two strictly anaerobic, crescent-shaped bacterial strains, designated WG T and Ycb08, were isolated from a cellulose-degrading mixed culture enriched from yak rumen contents. The strains were Gram-negative, non-spore-forming and motile, with four to six flagella situated at the centre of the concave side of the cell. The cells were 0.9–1.14–6 mm. Growth was observed at 27– 46 6C (optimum 39 6C) and pH 4.2–8.3 (optimum pH 7.0–7.2). Arabinose, glucose, mannose, cellobiose, lactose, sucrose, trehalose, melibiose, raffinose, salicin and aesculin were fermented. The end products of glucose fermentation were acetate, propionate and CO2. The G+C contents of strains WG T and Ycb08 were respectively 63.9±0.2 and 62.5±0.2 mol% (Tm). Phylogenetic analysis based on 16S rRNA gene sequences revealed that the two strains were related to the genera Mitsuokella and Selenomonas at similarity levels below 97%; however, they differed from members of the genus Mitsuokella in their flagellar arrangement. On the basis of phenotypic, genotypic and physiological evidence, strains WG T and Ycb08 are identified as members of a novel species of the genus Selenomonas, for which the name Selenomonas bovis sp. nov. is proposed. The type strain is WG T (5CGMCC 1.5073 T 5JCM 15470 T ).
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Selenomonas bovis sp. nov., isolated from yak rumen contents.
International journal of systematic and evolutionary microbiology, 2009Co-Authors: Kegui Zhang, Xiuzhu DongAbstract:Two strictly anaerobic, crescent-shaped bacterial strains, designated WGT and Ycb08, were isolated from a cellulose-degrading mixed culture enriched from yak rumen contents. The strains were Gram-negative, non-spore-forming and motile, with four to six flagella situated at the centre of the concave side of the cell. The cells were 0.9-1.1x4-6 microm. Growth was observed at 27-46 degrees C (optimum 39 degrees C) and pH 4.2-8.3 (optimum pH 7.0-7.2). Arabinose, glucose, mannose, cellobiose, lactose, sucrose, trehalose, melibiose, raffinose, salicin and aesculin were fermented. The end products of glucose fermentation were acetate, propionate and CO2. The G+C contents of strains WGT and Ycb08 were respectively 63.9+/-0.2 and 62.5+/-0.2 mol% (Tm). Phylogenetic analysis based on 16S rRNA gene sequences revealed that the two strains were related to the genera Mitsuokella and Selenomonas at similarity levels below 97%; however, they differed from members of the genus Mitsuokella in their flagellar arrangement. On the basis of phenotypic, genotypic and physiological evidence, strains WGT and Ycb08 are identified as members of a novel species of the genus Selenomonas, for which the name Selenomonas bovis sp. nov. is proposed. The type strain is WGT (=CGMCC 1.5073T=JCM 15470T).
S. A. Martin - One of the best experts on this subject based on the ideXlab platform.
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Cloning of the L-lactate dehydrogenase gene from the ruminal bacterium Selenomonas ruminantium HD4.
Current microbiology, 2002Co-Authors: Jeff D. Evans, S. A. MartinAbstract:A clone from a Selenomonas ruminantium HD4 Lambda ZAP® II genomic library was isolated by its ability to complement the anaerobic growth deficiency of an Escherichia coli (pfl, ldh) double mutant. The 1.0-kb insert from the clone was sequenced and revealed a single open reading frame (ORF, 957-bp) which was preceded by a putative Shine-Dalgarno (SD) sequence (AGGGGG). The potential SD sequence corresponded to 3′ 16S rRNA sequences of various Selenomonas strains. The ORF was predicted to encode a protein of 318 amino acids with a calculated molecular mass of 34,975 Da and an isoelectric point of 5.54. In addition, the ORF contained 51 mol % G + C and this is consistent with the average G + C content (54%) of the S. ruminantium chromosome. The cloned S. ruminantium gene exhibited 59% nucleotide identity and 61% deduced amino acid similarity with L-lactate dehydrogenases (L-LDH) of Pediococcus acidilactici and Bacillus megaterium, respectively. Incorporation of the cloned S. ruminantium gene into E. coli DC1368 (pfl, ldh) restored anaerobic growth on glucose and L-LDH activity was detected in cell extracts. Because lactate accumulation within the rumen can be detrimental to animal performance, characterizing the gene(s) involved in lactate production by predominant ruminal bacteria will lead to a better understanding of lactate metabolism within the rumen.
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Cloning of the O-acetylserine lyase gene from the ruminal bacterium Selenomonas ruminantium HD4.
Current microbiology, 2002Co-Authors: Jeff D. Evans, Sufian F. Al-khaldi, S. A. MartinAbstract:The gene coding for O-acetylserine lyase (OASL) was cloned from a Selenomonas ruminantium HD4 Lambda ZAP® II genomic library by degenerative probe hybridization and complementation. Sequence analysis revealed a 933 bp ORF with a G + C content of 53%. The ORF had significant homology with enzymes involved in cysteine biosynthesis. A CuraBLASTN™ homology search showed that the ORF shared 59% nucleotide identity with the cysK of Bacillus subtilis. The deduced amino acid sequence exhibited high (>70%) similarity with the CysK of B. subtilis and other cysteine synthesis proteins from Mycobacterium tuberculosis, Mycobacterium leprae, and Spinacia oleracea. Further analysis predicted that the gene product was a member of the pyridoxal phosphate enzyme family and of cytoplasmic origin. Phylogenetic analysis clustered the S. ruminantium gene product with the OASLa isoform of B. subtilis and the OASLb isoforms of Streptococcus suis, Escherichia coli, and Campylobacter jejuni. The OASL of S. ruminantium HD4 was also able to complement the cysM cysK double mutations in Escherichia coli NK3 and allow for growth on minimal media that contained either sulfate or thiosulfate as the sole source of sulfur. These results suggest that the gene functions as a cysM in S. ruminantium HD4. In conclusion, this research describes the cloning and expression of an O-acetylserine lyase gene from the predominant ruminal anaerobe S. ruminantium HD4. To our knowledge, this is the first report characterizing genes involved in sulfur metabolism from the genus Selenomonas.
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hexose phosphorylation by the ruminal bacterium Selenomonas ruminantium
Journal of Dairy Science, 1996Co-Authors: S. A. MartinAbstract:Abstract Three strains of Selenomonas ruminantium (D, GA192, and H18) were surveyed for phosphorylation of D-glucose and 2-deoxyglucose by phosphoenolpyruvate and ATP. Cells of all three strains that had been treated with toluene had high rates of hexose phosphorylation with either phosphoryl donor; this activity was constitutive in strain D. Glucose phosphorylation that was dependent on phosphoenolpyruvate was maximal at pH 7.2, remained fairly high at pH 6.5, but decreased (≥65%) at pH 5.0 for all strains. Cell extracts were used to evaluate the involvement of soluble kinases in 2-deoxyglucose phosphorylation. Both glucose and 2-deoxyglucose were phosphorylated by ATP, but phosphorylation of either hexose was negligible with phosphoenolpyruvate in each bacterium. Because phosphoenolpyruvate could not serve as a phosphoryl donor, the activity dependent on phosphoenolpyruvate in cells treated with toluene might have been due to a phosphotransferase system associated with the membrane. Unlabeled 2-deoxyglucose was a strong inhibitor (≥59%) of [ 14 C]glucose phosphorylation with ATP by cell extracts of all S. ruminantium strains, and unlabeled glucose was a strong inhibitor (≥78%) of [ 14 C]2-deoxyglucose phosphorylation with ATP. Based on Lineweaver-Burk kinetics, 2-deoxyglucose was a competitive inhibitor of initial rates of kinase activity in strains D, GA192, and H18. These results collectively suggest that glucose phosphorylation with phosphoenolpyruvate and 2-deoxyglucose phosphorylation with ATP are common traits in these strains of S. ruminantium .
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factors affecting l lactate utilization by Selenomonas ruminantium
Journal of Animal Science, 1994Co-Authors: David J Nisbet, S. A. MartinAbstract:Studies were conducted to evaluate factors that affect L-lactate utilization by the ruminal bacterium Selenomonas ruminantium HD4. L-Lactate uptake decreased over time both in the presence and absence of 10 mM L-malate. Compared with uptake in the absence of malate, 10 mM L-malate increased L- lactate uptake at 30 s and 45 min. Because L-malate had little effect on L-lactate uptake for cells grown on soluble carbohydrates compared to lactate-grown cells, it seems that the stimulation due to L-malate is inducible. Sodium concentrations between 25 and 100 mM stimulated long-term (45 min) L-lactate uptake in the presence of 10 mM L-malate, whereas uptake in the absence of L-malate was low regardless of the Na+ concentration, Monensin inhibited L-lactate uptake by 42%, and this is consistent with the involvement of Na+ in L-lactate utilization. Initial uptake (3 0 s ) of L- lactate was not dependent on Na+. L-Lactate uptake was stimulated by 10 mM L-malate at extracellular pH values between 4.0 and 8.0. No inhibition of L- lactate uptake was observed in the presence of 10 mM glucose, maltose, sucrose, xylose, or D-lactate. The metabolic inhibitors carbonyl cyanide m-chlorophenyl- hydrazone, 2,4-dinitrophenol, and NaF inhibited L- lactate uptake (> 79%), suggesting that protons may be involved in L-lactate uptake by this bacterium. Collectively, these experiments show that L-lactate uptake by S. ruminantium HD4 is stimulated in the presence of 10 mM L-malate at pH values and Na+ concentrations commonly found in the rumen.
