The Experts below are selected from a list of 3453 Experts worldwide ranked by ideXlab platform
Riikka Juvonen - One of the best experts on this subject based on the ideXlab platform.
-
Pectinatus sottacetonis sp. nov., isolated from a commercial pickle spoilage tank
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Jane M. Caldwell, Riikka Juvonen, James Brown, Fred BreidtAbstract:A strictly anaerobic, Gram-stain-negative, non-spore-forming, motile bacterium, designated strain FSRU B0405T, was isolated from a commercial pickle spoilage tank and characterized by biochemical, physiological and molecular biological methods. Analyses of the 16S rRNA gene sequence of strain FSRU B0405T showed affiliation to the class Negativicutes in the phylum Firmicutes , with the closest relatives being the type strains of Pectinatus haikarae (96 %) and Pectinatus brassicae (95 %). In maximum-likelihood and neighbour-joining phylogenetic trees, strain FSRU B0405T clustered definitively (in 100 % of bootstrapped trees) within the genus Pectinatus , but not specifically with any characterized species within this genus. Strain FSRU B0405T was a slightly curved rod, varying from 3 to 30 µm in length, motile with a distinctive X-wise movement, having flagella only on the concave side of the cell. The isolate produced acetate and propionate from fructose and glucose as major metabolites similar to type strains of species of the genus Pectinatus . The major fatty acids were C11 : 0, C13 : 0, C15 : 0, C13 : 0 3-OH, C17 : 1 and C18 : 1ω11t. Strain FSRU B0405T differed from the pickle wastewater strain, Pectinatus brassicae TYT, due to its lack of susceptibility to vancomycin, acetoin production, growth temperature range, acid production from adonitol, erythritol, glycerol, inositol, lactose, maltose, mannose, ribose, salicin, sorbitol, trehalose and xylitol and lack of hydrolysis of milk. Strain FSRU B0405T could be differentiated from other species of the genus Pectinatus both phenotypically and genetically. The results indicate that strain FSRU B0405T represents a novel species of the genus Pectinatus , for which the name Pectinatus sottacetonis sp. nov. is proposed. The type strain is FSRU B0405T ( = ATCC BAA-2501T = VTT E-113163T). An emended description of the genus Pectinatus is also provided.
-
Pectinatus sottacetonis sp. nov., isolated from a commercial pickle spoilage tank.
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Jane M. Caldwell, Riikka Juvonen, James W. Brown, Fred BreidtAbstract:A strictly anaerobic, Gram-stain-negative, non-spore-forming, motile bacterium, designated strain FSRU B0405T, was isolated from a commercial pickle spoilage tank and characterized by biochemical, physiological and molecular biological methods. Analyses of the 16S rRNA gene sequence of strain FSRU B0405T showed affiliation to the class Negativicutes in the phylum Firmicutes , with the closest relatives being the type strains of Pectinatus haikarae (96 %) and Pectinatus brassicae (95 %). In maximum-likelihood and neighbour-joining phylogenetic trees, strain FSRU B0405T clustered definitively (in 100 % of bootstrapped trees) within the genus Pectinatus , but not specifically with any characterized species within this genus. Strain FSRU B0405T was a slightly curved rod, varying from 3 to 30 µm in length, motile with a distinctive X-wise movement, having flagella only on the concave side of the cell. The isolate produced acetate and propionate from fructose and glucose as major metabolites similar to type strains of species of the genus Pectinatus . The major fatty acids were C11 : 0, C13 : 0, C15 : 0, C13 : 0 3-OH, C17 : 1 and C18 : 1ω11t. Strain FSRU B0405T differed from the pickle wastewater strain, Pectinatus brassicae TYT, due to its lack of susceptibility to vancomycin, acetoin production, growth temperature range, acid production from adonitol, erythritol, glycerol, inositol, lactose, maltose, mannose, ribose, salicin, sorbitol, trehalose and xylitol and lack of hydrolysis of milk. Strain FSRU B0405T could be differentiated from other species of the genus Pectinatus both phenotypically and genetically. The results indicate that strain FSRU B0405T represents a novel species of the genus Pectinatus , for which the name Pectinatus sottacetonis sp. nov. is proposed. The type strain is FSRU B0405T ( = ATCC BAA-2501T = VTT E-113163T). An emended description of the genus Pectinatus is also provided.
-
Megasphaera paucivorans sp. nov., Megasphaera sueciensis sp. nov. and Pectinatus haikarae sp. nov., isolated from brewery samples, and emended description of the genus Pectinatus
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: Riikka Juvonen, Maija-liisa SuihkoAbstract:Seven unidentified strictly anaerobic, Gram-negative, non-spore-forming bacteria from spoiled beer or the brewery environment were characterized. Based on 16S rRNA gene sequence analyses, all strains were affiliated to the Sporomusa sub-branch of the class 'Clostridia'. Three of the strains were non-motile cocci, on average 1.5 x 1.2 microm or 1.2 x 1.0 microm, occurring mainly singly or in pairs. They shared nearly identical (>99 %) 16S rRNA gene sequences, being most closely related to the species of the Megasphaera-Anaeroglobus group (< or =93.9 % similarity). According to DNA-DNA hybridization results, the coccoid strains represented two genospecies, neither of which was related to any of the recognized Megasphaera species. Several phenotypic characteristics and/or DNA G+C content also differentiated the strains from each other and from their closest relatives. The other four novel strains were motile, slightly curved to helical rods, 0.6-0.8 x 3-50 microm or more in size. They shared identical 16S rRNA gene sequences and ribofragment patterns. The highest 16S rRNA gene similarity was found between these isolates and Pectinatus cerevisiiphilus ATCC 29359T (95.6 %) and Pectinatus frisingensis ATCC 33332T (93.6 %). The novel strains also differed from recognized Pectinatus species in their sugar utilization, proteolytic activity, catalase activity, antibiotic resistance and temperature tolerance. The results suggest that the bacteria belong to three novel species, for which the names Megasphaera paucivorans sp. nov. (type strain VTT E-032341T = DSM 16981T), Megasphaera sueciensis sp. nov. (type strain VTT E-97791T = DSM 17042T) and Pectinatus haikarae sp. nov. (type strain VTT E-88329T = DSM 16980T) are proposed.
-
Detection of beer spoilage bacteria Megasphaera and Pectinatus by polymerase chain reaction and colorimetric microplate hybridization
International journal of food microbiology, 1998Co-Authors: Reetta Satokari, Riikka Juvonen, Kirstie Mallison, Auli HaikaraAbstract:Abstract Anaerobic bacteria of the genera Megasphaera and Pectinatus cause beer spoilage by producing off flavours and turbidity. Detection of these organisms is complicated by the strict anaerobic conditions and lengthy incubation times required for their cultivation, consequently there is a need for more rapid detection methods. A polymerase chain reaction (PCR) method and a colorimetric microplate hybridization assay were developed for the rapid and specific detection of Megasphaera cerevisiae and Pectinatus spp. A biotinylated primer pair was designed for the amplification of a 403 base pair (bp) fragment of the M. cerevisiae 16S rRNA gene and a primer pair from literature was used for the amplification of an 816 bp fragment of Pectinatus 16S rRNA gene. Amplified PCR products were analyzed by the colorimetric microplate hybridization method in which a biotinylated PCR product was captured by streptavidin and hybridized with a digoxigenin-labelled oligonucleotide probe. In the final step an enzyme-linked antibody and a colorimetric reaction were utilized. A simple and rapid sample treatment was set up for the PCR detection of contaminants in beer. Detection of M. cerevisiae (≥5·10 3 colony forming units [cfu]/100 ml) and Pectinatus frisingensis (≥5·10 5 cfu/100 ml) in beer was successful, but the sensitivity of the assay still needs to be improved for direct detection of the small amounts of bacteria present in beer.
-
Detection of Pectinatus Beer Spoilage Bacteria by Using the Polymerase Chain Reaction.
Journal of food protection, 1997Co-Authors: Reetta Satokari, Riikka Juvonen, Auli HaikaraAbstract:Anaerobic bacteria of the genus Pectinatus cause beer spoilage by producing off flavors and turbidity. In unpasteurized beer even a small initial amount of contamination is likely to lead to a defective product. Detection of Pectinatus by traditional microbiological techniques is time-consuming and not practical as a preventive product control measure. In this paper Pectinatus -specific primers capable of discriminating among other beer contaminants by polymerase chain reaction are described. The present procedure, which includes the isolation of DNA from the contaminated beer sample, the polymerase chain reaction, and the electrophoretic identification of the reaction products could be performed within 10 h. The detection level in inoculated beer samples was ca. 20 cells per ml. The technique therefore has a potential in routine product control.
Fred Breidt - One of the best experts on this subject based on the ideXlab platform.
-
Pectinatus sottacetonis sp. nov., isolated from a commercial pickle spoilage tank
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Jane M. Caldwell, Riikka Juvonen, James Brown, Fred BreidtAbstract:A strictly anaerobic, Gram-stain-negative, non-spore-forming, motile bacterium, designated strain FSRU B0405T, was isolated from a commercial pickle spoilage tank and characterized by biochemical, physiological and molecular biological methods. Analyses of the 16S rRNA gene sequence of strain FSRU B0405T showed affiliation to the class Negativicutes in the phylum Firmicutes , with the closest relatives being the type strains of Pectinatus haikarae (96 %) and Pectinatus brassicae (95 %). In maximum-likelihood and neighbour-joining phylogenetic trees, strain FSRU B0405T clustered definitively (in 100 % of bootstrapped trees) within the genus Pectinatus , but not specifically with any characterized species within this genus. Strain FSRU B0405T was a slightly curved rod, varying from 3 to 30 µm in length, motile with a distinctive X-wise movement, having flagella only on the concave side of the cell. The isolate produced acetate and propionate from fructose and glucose as major metabolites similar to type strains of species of the genus Pectinatus . The major fatty acids were C11 : 0, C13 : 0, C15 : 0, C13 : 0 3-OH, C17 : 1 and C18 : 1ω11t. Strain FSRU B0405T differed from the pickle wastewater strain, Pectinatus brassicae TYT, due to its lack of susceptibility to vancomycin, acetoin production, growth temperature range, acid production from adonitol, erythritol, glycerol, inositol, lactose, maltose, mannose, ribose, salicin, sorbitol, trehalose and xylitol and lack of hydrolysis of milk. Strain FSRU B0405T could be differentiated from other species of the genus Pectinatus both phenotypically and genetically. The results indicate that strain FSRU B0405T represents a novel species of the genus Pectinatus , for which the name Pectinatus sottacetonis sp. nov. is proposed. The type strain is FSRU B0405T ( = ATCC BAA-2501T = VTT E-113163T). An emended description of the genus Pectinatus is also provided.
-
Pectinatus sottacetonis sp. nov., isolated from a commercial pickle spoilage tank.
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Jane M. Caldwell, Riikka Juvonen, James W. Brown, Fred BreidtAbstract:A strictly anaerobic, Gram-stain-negative, non-spore-forming, motile bacterium, designated strain FSRU B0405T, was isolated from a commercial pickle spoilage tank and characterized by biochemical, physiological and molecular biological methods. Analyses of the 16S rRNA gene sequence of strain FSRU B0405T showed affiliation to the class Negativicutes in the phylum Firmicutes , with the closest relatives being the type strains of Pectinatus haikarae (96 %) and Pectinatus brassicae (95 %). In maximum-likelihood and neighbour-joining phylogenetic trees, strain FSRU B0405T clustered definitively (in 100 % of bootstrapped trees) within the genus Pectinatus , but not specifically with any characterized species within this genus. Strain FSRU B0405T was a slightly curved rod, varying from 3 to 30 µm in length, motile with a distinctive X-wise movement, having flagella only on the concave side of the cell. The isolate produced acetate and propionate from fructose and glucose as major metabolites similar to type strains of species of the genus Pectinatus . The major fatty acids were C11 : 0, C13 : 0, C15 : 0, C13 : 0 3-OH, C17 : 1 and C18 : 1ω11t. Strain FSRU B0405T differed from the pickle wastewater strain, Pectinatus brassicae TYT, due to its lack of susceptibility to vancomycin, acetoin production, growth temperature range, acid production from adonitol, erythritol, glycerol, inositol, lactose, maltose, mannose, ribose, salicin, sorbitol, trehalose and xylitol and lack of hydrolysis of milk. Strain FSRU B0405T could be differentiated from other species of the genus Pectinatus both phenotypically and genetically. The results indicate that strain FSRU B0405T represents a novel species of the genus Pectinatus , for which the name Pectinatus sottacetonis sp. nov. is proposed. The type strain is FSRU B0405T ( = ATCC BAA-2501T = VTT E-113163T). An emended description of the genus Pectinatus is also provided.
Jane M. Caldwell - One of the best experts on this subject based on the ideXlab platform.
-
Pectinatus sottacetonis sp. nov., isolated from a commercial pickle spoilage tank
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Jane M. Caldwell, Riikka Juvonen, James Brown, Fred BreidtAbstract:A strictly anaerobic, Gram-stain-negative, non-spore-forming, motile bacterium, designated strain FSRU B0405T, was isolated from a commercial pickle spoilage tank and characterized by biochemical, physiological and molecular biological methods. Analyses of the 16S rRNA gene sequence of strain FSRU B0405T showed affiliation to the class Negativicutes in the phylum Firmicutes , with the closest relatives being the type strains of Pectinatus haikarae (96 %) and Pectinatus brassicae (95 %). In maximum-likelihood and neighbour-joining phylogenetic trees, strain FSRU B0405T clustered definitively (in 100 % of bootstrapped trees) within the genus Pectinatus , but not specifically with any characterized species within this genus. Strain FSRU B0405T was a slightly curved rod, varying from 3 to 30 µm in length, motile with a distinctive X-wise movement, having flagella only on the concave side of the cell. The isolate produced acetate and propionate from fructose and glucose as major metabolites similar to type strains of species of the genus Pectinatus . The major fatty acids were C11 : 0, C13 : 0, C15 : 0, C13 : 0 3-OH, C17 : 1 and C18 : 1ω11t. Strain FSRU B0405T differed from the pickle wastewater strain, Pectinatus brassicae TYT, due to its lack of susceptibility to vancomycin, acetoin production, growth temperature range, acid production from adonitol, erythritol, glycerol, inositol, lactose, maltose, mannose, ribose, salicin, sorbitol, trehalose and xylitol and lack of hydrolysis of milk. Strain FSRU B0405T could be differentiated from other species of the genus Pectinatus both phenotypically and genetically. The results indicate that strain FSRU B0405T represents a novel species of the genus Pectinatus , for which the name Pectinatus sottacetonis sp. nov. is proposed. The type strain is FSRU B0405T ( = ATCC BAA-2501T = VTT E-113163T). An emended description of the genus Pectinatus is also provided.
-
Pectinatus sottacetonis sp. nov., isolated from a commercial pickle spoilage tank.
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Jane M. Caldwell, Riikka Juvonen, James W. Brown, Fred BreidtAbstract:A strictly anaerobic, Gram-stain-negative, non-spore-forming, motile bacterium, designated strain FSRU B0405T, was isolated from a commercial pickle spoilage tank and characterized by biochemical, physiological and molecular biological methods. Analyses of the 16S rRNA gene sequence of strain FSRU B0405T showed affiliation to the class Negativicutes in the phylum Firmicutes , with the closest relatives being the type strains of Pectinatus haikarae (96 %) and Pectinatus brassicae (95 %). In maximum-likelihood and neighbour-joining phylogenetic trees, strain FSRU B0405T clustered definitively (in 100 % of bootstrapped trees) within the genus Pectinatus , but not specifically with any characterized species within this genus. Strain FSRU B0405T was a slightly curved rod, varying from 3 to 30 µm in length, motile with a distinctive X-wise movement, having flagella only on the concave side of the cell. The isolate produced acetate and propionate from fructose and glucose as major metabolites similar to type strains of species of the genus Pectinatus . The major fatty acids were C11 : 0, C13 : 0, C15 : 0, C13 : 0 3-OH, C17 : 1 and C18 : 1ω11t. Strain FSRU B0405T differed from the pickle wastewater strain, Pectinatus brassicae TYT, due to its lack of susceptibility to vancomycin, acetoin production, growth temperature range, acid production from adonitol, erythritol, glycerol, inositol, lactose, maltose, mannose, ribose, salicin, sorbitol, trehalose and xylitol and lack of hydrolysis of milk. Strain FSRU B0405T could be differentiated from other species of the genus Pectinatus both phenotypically and genetically. The results indicate that strain FSRU B0405T represents a novel species of the genus Pectinatus , for which the name Pectinatus sottacetonis sp. nov. is proposed. The type strain is FSRU B0405T ( = ATCC BAA-2501T = VTT E-113163T). An emended description of the genus Pectinatus is also provided.
Maija-liisa Suihko - One of the best experts on this subject based on the ideXlab platform.
-
Megasphaera paucivorans sp. nov., Megasphaera sueciensis sp. nov. and Pectinatus haikarae sp. nov., isolated from brewery samples, and emended description of the genus Pectinatus
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: Riikka Juvonen, Maija-liisa SuihkoAbstract:Seven unidentified strictly anaerobic, Gram-negative, non-spore-forming bacteria from spoiled beer or the brewery environment were characterized. Based on 16S rRNA gene sequence analyses, all strains were affiliated to the Sporomusa sub-branch of the class 'Clostridia'. Three of the strains were non-motile cocci, on average 1.5 x 1.2 microm or 1.2 x 1.0 microm, occurring mainly singly or in pairs. They shared nearly identical (>99 %) 16S rRNA gene sequences, being most closely related to the species of the Megasphaera-Anaeroglobus group (< or =93.9 % similarity). According to DNA-DNA hybridization results, the coccoid strains represented two genospecies, neither of which was related to any of the recognized Megasphaera species. Several phenotypic characteristics and/or DNA G+C content also differentiated the strains from each other and from their closest relatives. The other four novel strains were motile, slightly curved to helical rods, 0.6-0.8 x 3-50 microm or more in size. They shared identical 16S rRNA gene sequences and ribofragment patterns. The highest 16S rRNA gene similarity was found between these isolates and Pectinatus cerevisiiphilus ATCC 29359T (95.6 %) and Pectinatus frisingensis ATCC 33332T (93.6 %). The novel strains also differed from recognized Pectinatus species in their sugar utilization, proteolytic activity, catalase activity, antibiotic resistance and temperature tolerance. The results suggest that the bacteria belong to three novel species, for which the names Megasphaera paucivorans sp. nov. (type strain VTT E-032341T = DSM 16981T), Megasphaera sueciensis sp. nov. (type strain VTT E-97791T = DSM 17042T) and Pectinatus haikarae sp. nov. (type strain VTT E-88329T = DSM 16980T) are proposed.
-
Characterization of Pectinatus and Megasphaera Strains by Automated Ribotyping
Journal of the Institute of Brewing, 2001Co-Authors: Maija-liisa Suihko, Auli HaikaraAbstract:A total of 32 Pectinatus and Megasphaera strains, isolated from spoiled beer or brewery environments and identified by conventional methods, were analysed by the automated RiboPrinter® System. One strain from each ribotype was further subjected to partial 16S rDNA sequencing to confirm the ribotyping results. The restriction enzyme EcoRI was used in ribotyping of Pectinatus strains. Eight strains, identified by conventional tests as P. cerevisiiphilus, generated five different ribotypes. The strains of three types were considered to be members of P. cerevisiiphilus, but the strains of two types were most probably members of a new species within the genus Pectinatus. The 24 strains identified by conventional tests as P. frisingenis generated nine different ribotypes. The similarity between the ribotypes was rather low, but all these strains obviously belonged to the same species. Thirteen Megasphaera cerevisiae strains were analysed with three restriction enzymes EcoRI, Pstl and PvuII and four, six and three different ribotypes, respectively, were generated resulting in seven different combinations. The best discrimination among these strains was obtained with Pstl. According to these results 12 of 13 brewery strains were considered to be M. cerevisiae, but one strain most probably represented a new species within the genus Megasphaera. During the work, 14 RiboPrint® patterns of Pectinatus, five of Megasphaera, two of Selenomonas and two of Zymophilus were created with EcoRI. In addition seven patterns of Megasphaera were created with Pstl and four with Pvull. All these identification patterns (genetic fingerprints) were saved at the database of VTT for future use.
Auli Haikara - One of the best experts on this subject based on the ideXlab platform.
-
Lipopolysaccharides of anaerobic beer spoilage bacteria of the genus Pectinatus– lipopolysaccharides of a Gram‐positive genus
FEMS microbiology reviews, 2004Co-Authors: Ilkka M. Helander, Auli Haikara, Irina Sadovskaya, Evgeny Vinogradov, Mirja Salkinoja-salonenAbstract:Bacteria of the genus Pectinatus emerged during the seventies as contaminants and spoilage organisms in packaged beer. This genus comprises two species, Pectinatus cerevisiiphilus and Pectinatus frisingensis; both are strict anaerobes. On the basis of genomic properties the genus is placed among low GC Gram-positive bacteria (phylum Firmicutes, class Clostridia, order Clostridiales, family Acidaminococcaceae). Despite this assignment, Pectinatus bacteria possess an outer membrane and lipopolysaccharide (LPS) typical of Gram-negative bacteria. The present review compiles the structural and compositional studies performed on Pectinatus LPS. These lipopolysaccharides exhibit extensive heterogeneity, i.e. several macromolecularly and structurally distinct LPS molecules are produced by each strain. Whereas heterogeneity is a common property in lipopolysaccharides, Pectinatus LPS have been shown to contain exceptional carbohydrate structures, consisting of a fairly conserved core region that carries a large non-repetitive saccharide that probably replaces the O-specific chain. Such structures represent a novel architectural principle of the LPS molecule.
-
lipopolysaccharides of anaerobic beer spoilage bacteria of the genus Pectinatus lipopolysaccharides of a gram positive genus
Fems Microbiology Reviews, 2004Co-Authors: Ilkka M. Helander, Auli Haikara, Irina Sadovskaya, Evgeny Vinogradov, Mirja SalkinojasalonenAbstract:Bacteria of the genus Pectinatus emerged during the seventies as contaminants and spoilage organisms in packaged beer. This genus comprises two species, Pectinatus cerevisiiphilus and Pectinatus frisingensis; both are strict anaerobes. On the basis of genomic properties the genus is placed among low GC Gram-positive bacteria (phylum Firmicutes, class Clostridia, order Clostridiales, family Acidaminococcaceae). Despite this assignment, Pectinatus bacteria possess an outer membrane and lipopolysaccharide (LPS) typical of Gram-negative bacteria. The present review compiles the structural and compositional studies performed on Pectinatus LPS. These lipopolysaccharides exhibit extensive heterogeneity, i.e. several macromolecularly and structurally distinct LPS molecules are produced by each strain. Whereas heterogeneity is a common property in lipopolysaccharides, Pectinatus LPS have been shown to contain exceptional carbohydrate structures, consisting of a fairly conserved core region that carries a large non-repetitive saccharide that probably replaces the O-specific chain. Such structures represent a novel architectural principle of the LPS molecule.
-
Characterization of Pectinatus and Megasphaera Strains by Automated Ribotyping
Journal of the Institute of Brewing, 2001Co-Authors: Maija-liisa Suihko, Auli HaikaraAbstract:A total of 32 Pectinatus and Megasphaera strains, isolated from spoiled beer or brewery environments and identified by conventional methods, were analysed by the automated RiboPrinter® System. One strain from each ribotype was further subjected to partial 16S rDNA sequencing to confirm the ribotyping results. The restriction enzyme EcoRI was used in ribotyping of Pectinatus strains. Eight strains, identified by conventional tests as P. cerevisiiphilus, generated five different ribotypes. The strains of three types were considered to be members of P. cerevisiiphilus, but the strains of two types were most probably members of a new species within the genus Pectinatus. The 24 strains identified by conventional tests as P. frisingenis generated nine different ribotypes. The similarity between the ribotypes was rather low, but all these strains obviously belonged to the same species. Thirteen Megasphaera cerevisiae strains were analysed with three restriction enzymes EcoRI, Pstl and PvuII and four, six and three different ribotypes, respectively, were generated resulting in seven different combinations. The best discrimination among these strains was obtained with Pstl. According to these results 12 of 13 brewery strains were considered to be M. cerevisiae, but one strain most probably represented a new species within the genus Megasphaera. During the work, 14 RiboPrint® patterns of Pectinatus, five of Megasphaera, two of Selenomonas and two of Zymophilus were created with EcoRI. In addition seven patterns of Megasphaera were created with Pstl and four with Pvull. All these identification patterns (genetic fingerprints) were saved at the database of VTT for future use.
-
Detection of beer spoilage bacteria Megasphaera and Pectinatus by polymerase chain reaction and colorimetric microplate hybridization
International journal of food microbiology, 1998Co-Authors: Reetta Satokari, Riikka Juvonen, Kirstie Mallison, Auli HaikaraAbstract:Abstract Anaerobic bacteria of the genera Megasphaera and Pectinatus cause beer spoilage by producing off flavours and turbidity. Detection of these organisms is complicated by the strict anaerobic conditions and lengthy incubation times required for their cultivation, consequently there is a need for more rapid detection methods. A polymerase chain reaction (PCR) method and a colorimetric microplate hybridization assay were developed for the rapid and specific detection of Megasphaera cerevisiae and Pectinatus spp. A biotinylated primer pair was designed for the amplification of a 403 base pair (bp) fragment of the M. cerevisiae 16S rRNA gene and a primer pair from literature was used for the amplification of an 816 bp fragment of Pectinatus 16S rRNA gene. Amplified PCR products were analyzed by the colorimetric microplate hybridization method in which a biotinylated PCR product was captured by streptavidin and hybridized with a digoxigenin-labelled oligonucleotide probe. In the final step an enzyme-linked antibody and a colorimetric reaction were utilized. A simple and rapid sample treatment was set up for the PCR detection of contaminants in beer. Detection of M. cerevisiae (≥5·10 3 colony forming units [cfu]/100 ml) and Pectinatus frisingensis (≥5·10 5 cfu/100 ml) in beer was successful, but the sensitivity of the assay still needs to be improved for direct detection of the small amounts of bacteria present in beer.
-
Detection of Pectinatus Beer Spoilage Bacteria by Using the Polymerase Chain Reaction.
Journal of food protection, 1997Co-Authors: Reetta Satokari, Riikka Juvonen, Auli HaikaraAbstract:Anaerobic bacteria of the genus Pectinatus cause beer spoilage by producing off flavors and turbidity. In unpasteurized beer even a small initial amount of contamination is likely to lead to a defective product. Detection of Pectinatus by traditional microbiological techniques is time-consuming and not practical as a preventive product control measure. In this paper Pectinatus -specific primers capable of discriminating among other beer contaminants by polymerase chain reaction are described. The present procedure, which includes the isolation of DNA from the contaminated beer sample, the polymerase chain reaction, and the electrophoretic identification of the reaction products could be performed within 10 h. The detection level in inoculated beer samples was ca. 20 cells per ml. The technique therefore has a potential in routine product control.
