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1. Non-biogroup 1 or 2 Strains of the Emerging Zoonotic Pathogen Escherichia albertii, Their Proposed Assignment to Biogroup 3, and Their Commonly Detected Characteristics

Author

Koichi Murakami, Eriko Maeda-Mitani, Hirokazu Kimura, Mikiko Honda, Tetsuya Ikeda, Wakana Sugitani, Takayuki Konno, Kimiko Kawano, Yoshiki Etoh, Nobuyuki Sera, Fuminori Mizukoshi, Takehito Saitoh, Yoshiaki Kawamura, Taisei Ishioka, Makoto Ohnishi, Kazunori Oishi, and Shuji Fujimoto

Subjects
biogroups, Escherichia albertii, food microbiology, identification, public health, Microbiology, QR1-502
Abstract

Escherichia albertii, a zoonotic enteropathogen, is responsible for outbreaks of disease in humans. Identifying strains of E. albertii by phenotypic characterization tests is difficult because of its poorly defined properties. Screening its phenotypic characteristics is, nevertheless, a necessary prerequisite for further genetic analysis of its properties, and species-specific polymerase chain reaction (PCR) analysis can be used to type the pathogen. While two E. albertii biogroups (1 and 2) have been described, strains with characteristics divergent from both biogroups have been reported worldwide. The aim of the present study was to evaluate the characteristics of non-biogroup 1 or 2 strains, and discern the characteristics common to all of the E. albertii strains from this study. Altogether, 107/414 field isolates were selected for examination based on pulsed-field gel electrophoresis analysis. The 107 strains were isolated from 92 sources, including humans and pigeon feces, other wild birds, and retail chicken livers. All strains were then examined using various culture-based, biochemical (API 50CHE tests, API Zym test, and others) and molecular (virulence gene screening, multi-locus sequence analysis) testing methods. Our results revealed that all field strains (n = 107) showed non-biogroup 1 or 2 characteristics, with multiple sequence differences. Variations in indole production and the lysine decarboxylase activity profiles among the isolates made identification of E. albertii very difficult. Therefore, we propose that non-biogroup 1 or 2 of E. albertii should be assigned to biogroup 3 to make screening of them easier in public health and clinical laboratory settings. Clearly, having group criteria for indole-negative/lysine-positive, indole-positive/lysine-negative, and indole-positive/lysine-positive E. albertii biogroups 1, 2, and 3 strains, respectively, should provide for more accurate identification of E. albertii isolates. Based on our findings, we recommend that isolates displaying phenotype mobility-negativity (sulfide-indole-motility medium, 37°C), hydrogen sulfide production-negativity (triple sugar iron medium), acid production-negativity from xylose, negative β-glucuronidase activity properties, and showing indole production and lysine decarboxylase activity profiles in accordance with one of the three biogroups, should be further assessed using an E. albertii-specific PCR assay.

Published
2019
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2. Non-biogroup 1 or 2 Strains of the Emerging Zoonotic Pathogen Escherichia albertii , Their Proposed Assignment to Biogroup 3, and Their Commonly Detected Characteristics.

Author

Murakami, Koichi, Maeda-Mitani, Eriko, Kimura, Hirokazu, Honda, Mikiko, Ikeda, Tetsuya, Sugitani, Wakana, Konno, Takayuki, Kawano, Kimiko, Etoh, Yoshiki, Sera, Nobuyuki, Mizukoshi, Fuminori, Saitoh, Takehito, Kawamura, Yoshiaki, Ishioka, Taisei, Ohnishi, Makoto, Oishi, Kazunori, and Fujimoto, Shuji

Subjects
PULSED-field gel electrophoresis, ESCHERICHIA, HYDROGEN sulfide, BIRDS, POLYMERASE chain reaction, DISEASE outbreaks
Abstract

Escherichia albertii , a zoonotic enteropathogen, is responsible for outbreaks of disease in humans. Identifying strains of E. albertii by phenotypic characterization tests is difficult because of its poorly defined properties. Screening its phenotypic characteristics is, nevertheless, a necessary prerequisite for further genetic analysis of its properties, and species-specific polymerase chain reaction (PCR) analysis can be used to type the pathogen. While two E. albertii biogroups (1 and 2) have been described, strains with characteristics divergent from both biogroups have been reported worldwide. The aim of the present study was to evaluate the characteristics of non-biogroup 1 or 2 strains, and discern the characteristics common to all of the E. albertii strains from this study. Altogether, 107/414 field isolates were selected for examination based on pulsed-field gel electrophoresis analysis. The 107 strains were isolated from 92 sources, including humans and pigeon feces, other wild birds, and retail chicken livers. All strains were then examined using various culture-based, biochemical (API 50CHE tests, API Zym test, and others) and molecular (virulence gene screening, multi-locus sequence analysis) testing methods. Our results revealed that all field strains (n = 107) showed non-biogroup 1 or 2 characteristics, with multiple sequence differences. Variations in indole production and the lysine decarboxylase activity profiles among the isolates made identification of E. albertii very difficult. Therefore, we propose that non-biogroup 1 or 2 of E. albertii should be assigned to biogroup 3 to make screening of them easier in public health and clinical laboratory settings. Clearly, having group criteria for indole-negative/lysine-positive, indole-positive/lysine-negative, and indole-positive/lysine-positive E. albertii biogroups 1, 2, and 3 strains, respectively, should provide for more accurate identification of E. albertii isolates. Based on our findings, we recommend that isolates displaying phenotype mobility-negativity (sulfide-indole-motility medium, 37°C), hydrogen sulfide production-negativity (triple sugar iron medium), acid production-negativity from xylose, negative β-glucuronidase activity properties, and showing indole production and lysine decarboxylase activity profiles in accordance with one of the three biogroups, should be further assessed using an E. albertii -specific PCR assay. [ABSTRACT FROM AUTHOR]

Published
2019
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3. Localization of large trees in the taiga stands and geoactive zone

Author

Rogozin M.

Subjects
Siberian pine, small–leaved linden, biogroups, Siberian spruce, Finnish spruce, plus trees, geo–active zone
Abstract

Studied a sample of the largest trees Siberian pine (Pinus sibirica), Siberian spruce (Picea obovata), Finnish spruce (Picea ×fennica), silver birch (Betula pendula) and small–leaved linden (Tilia cordata) subzone in the middle (“Vishera” Reserve) and in the subzone of the southern taiga (forest Perm) in the natural old–growth forests, only 82 pcs., Which are its parameters were close to the plus trees. Near these trees were determined 8 types of geo–active zones (hereinafter “zone”) using biolocation method. It was found that the largest trees in the Siberian pine forests of the reserve formed on a completely unique combination of these zones, with diameters of 1, 3, 4.5 meters with zones of large diameters. 16, 32, 55 m in the same forests of large trees Siberian spruce were localized exclusively on another combination of zones, with diameters of only 1 and 8 m. Further, in the southern taiga, we have studied the large Finnish spruce trees in spruce and linden forest. They were localized on a completely different combination areas than Siberian spruce: 1 m and 3–4.5 m, with preference zones 4.5 m where the biggest linden trees always met on Zones 1 m and within chains of these areas, and. in the majority of cases they were combined with zones of 3–4.5 m, with a preference for zones 3 m, indicating some differences in energy preferences spruce and linden. We were also studied biogroups one or two rocks; it turned out that they form 34–50% of the large trees and the zone diameter 1 or 4.5 m was located most often exactly in the middle between the trees. In this zone diameter is always greater than the distance between the trees, and may therefore be considered biogroups two trees with the distance of 4.0 m even if they are located in an area with a diameter of, for example, 4.5 m.

Published
2016
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4. Zoobenthic invertebrate of Anzali Lagoon and their relation with organic matter of the bottom

Author

Mirzajani, A., Yosefzadeh, A., and Ganea, A.

Subjects
Anzali Lagoon, Organic, Tubificidae, Substances, Dendrograms, Ecology, Organisms, Adaptable, Density, Iran, Chironomidae, Benthos, Culicidae, Zoobenthic, Cluster, Biogroups, Clay, Amphipoda, Invertebrate, Biology, Ephemeroptera
Abstract

The study was conducted in Anzali Lagoon (37 ̊ 28 N, 45 ̊ 25 E) in 38 stations during April 1994 to March 1996. In this study 13 biogroups were separated and counted. The abundance of most biogroups was very low, while that of the groups Chironomidae and Tubificidae were high and the abundance of the biogroup Amphipoda, Culicidae and Ephemeroptera was lower than the mentioned groups. Tubificidae was seen in all stations and all months of the year and its maximum density was 3740 organisms in each square meter. After Tubificidae the Chironomidae family had the second level of density. The total percentage of the organic substances of the bottom had not considerable changes in different month and its mean amount differed from 2.57% in the site of breakwater and the sea to 27.1% (maximum) in central portion of the lagoon. No considerable relation was observed between the amount of organic matter and the abundance of benthos in the region. According to the obtained results, Tubificidae and Chironomidae families showed little correlation with the bottom organic substances. The correlation of biogroup Ephemeroptera with the organic substances was greater than that of the 2 mentioned groups. Using the cluster type analysis and dendrograms made clear that the relation of biogroups Culicidae, Ephemeroptera and Tubificidae with the bottom organic substances was more than that of Chironomidae. Culicidae and Chironomidae showed close correlation with silt and clay of the bottom, but Tubificidae was more adaptable with the bottom fine particles.

Published
1999

5. La Théorie des groupes : application aux éclaircies de futaie régulière

Author

Hans-Jürgen Otto and Yves Bastien

Subjects
0106 biological sciences, Biogroupe, Théorie groupe arbres -- Europe, Population structure, Group composition, 01 natural sciences, Vegetation dynamics, Theory, tree group theory -- Europe, ComputingMilieux_MISCELLANEOUS, Ecology, Even aged forest stand, Plant sociology, Composition groupe, Windfall, Dynamique groupe, Forestry, Group dynamic, Structure végétation, Forêt primaire, Geography, Vegetation structure, Europe Est, [SDE]Environmental Sciences, Peuplement forestier artificiel, Production quality, Forest thinning, High forest, 1920-1930, Population dynamics, Application, Dynamique population, Qualité production, Eclaircie forestière, Plant community, Eastern Europe, 010603 evolutionary biology, Group dynamics, Peuplement forestier équienne, Chablis, biogroups, Dynamique végétation, Artificial forest stand, Ecologie, 010604 marine biology & hydrobiology, Phytosociologie, 15. Life on land, Groupement végétal, Futaie, Théorie, Primary forest, Structure population
Abstract

L’article qui suit porte sur les groupes d’arbres (1). Cette theorie des groupes d’arbres, developpee dans les pays de l’Est a partir des annees 1920-1925, s’appuie sur l’observation de l’evolution naturelle de la foret vierge pour privilegier en foret cultivee les arbres dominants et de qualite sans tenir compte de leur espacement. Les auteurs, tout en n’ignorant pas les objections possibles, pensent que cette theorie merite d’etre connue et experimentee. Que ceux des lecteurs qui en voient les imperfections et les inconvenients le fassent connaitre a la Revue forestiere francaise.

Published
1998
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