1
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Kim E, Kim DS, Yang SM, Kim HY. The accurate identification and quantification of six Enterococcus species using quantitative polymerase chain reaction based novel DNA markers. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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2
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Zarzecka U, Zadernowska A, Chajęcka-Wierzchowska W. Effects of osmotic and high pressure stress on expression of virulence factors among Enterococcus spp. isolated from food of animal origin. Food Microbiol 2021; 102:103900. [PMID: 34809932 DOI: 10.1016/j.fm.2021.103900] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 08/22/2021] [Accepted: 09/09/2021] [Indexed: 01/01/2023]
Abstract
The aim of study was to determine the occurrence of virulence factors and virulence-related genes among enterococci isolated from food of animal origin and effects of osmotic and high pressure stress on expression of virulence-related genes. The number of 78 isolates were analyzed. None of them showed a strong ability to form biofilm, 38.5% (n = 30) had the slime production ability, 41% (n = 32) had gelatinase activity, γ -type hemolysis was observed in 55% of isolates, and α-type hemolysis in 45%. All of the isolates carried 1-13 virulence-related genes. The most common genes were gelE (85.9%), sprE (78.2%) and asa1 (75.6%). There were also observed changes in the expression of the gelE, esp, asa1 and cylL genes in response to various NaCl concentration and high pressure processing. Results obtained in this study indicate that enterococci isolated from food may act as reservoirs of virulence genes. The presence of virulence factors among enterococci, especially the ability to biofilm formation is important for food safety and the protection of public health. The results presented in our work demonstrate that stress that can occur during food preservation and food processing can induce the changes in the virulence-related genes expression.
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Affiliation(s)
- Urszula Zarzecka
- Chair of Industrial and Food Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726, Olsztyn, Poland.
| | - Anna Zadernowska
- Chair of Industrial and Food Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726, Olsztyn, Poland
| | - Wioleta Chajęcka-Wierzchowska
- Chair of Industrial and Food Microbiology, Faculty of Food Science, University of Warmia and Mazury, Plac Cieszyński 1, 10-726, Olsztyn, Poland
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3
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Enterococci isolated from plant-derived food - Analysis of antibiotic resistance and the occurrence of resistance genes. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2020.110549] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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4
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Chajęcka-Wierzchowska W, Zadernowska A, García-Solache M. Ready-to-eat dairy products as a source of multidrug-resistant Enterococcus strains: Phenotypic and genotypic characteristics. J Dairy Sci 2020; 103:4068-4077. [DOI: 10.3168/jds.2019-17395] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Accepted: 01/16/2020] [Indexed: 12/22/2022]
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5
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Perri G, Calabrese FM, Rizzello CG, De Angelis M, Gobbetti M, Calasso M. Sprouting process affects the lactic acid bacteria and yeasts of cereal, pseudocereal and legume flours. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109314] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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6
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Microbiota of Sardinian Goat's Milk and Preliminary Characterization of Prevalent LAB Species for Starter or Adjunct Cultures Development. BIOMED RESEARCH INTERNATIONAL 2019; 2019:6131404. [PMID: 31360718 PMCID: PMC6644507 DOI: 10.1155/2019/6131404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 06/03/2019] [Accepted: 06/13/2019] [Indexed: 11/21/2022]
Abstract
This work was performed to study the microbiota of raw goat's milk (67 samples) collected in different areas of Sardinia, in order to select autochthonous lactic acid bacteria (LAB) strains for use in goat cheese manufacturing. Total mesophilic bacteria ranged between 105 and 107 cfu/mL; mean counts of Enterobacteriaceae did not exceed 4 log cfu/mL whereas those of E. coli and coagulase-positive staphylococci were lower than 1.5 and 2 log ufc /ml, respectively. Neither Salmonella spp. nor Listeria monocytogenes were recovered. The numbers of total LAB were in the range from 104 to 107 cfu/mL and mean yeasts counts varied between 103 and 105 cfu/mL. The most frequently isolated LAB species were Lactococcus lactis subsp. lactis and Lactobacillus paracasei. The presence of Enterococcus faecium was also noteworthy. The in vitro study of some functional characteristics related to technological properties of the strains belonging to these species allowed to point out some strains possessing good potential for use as adjunct or starter cultures in the production of cheese.
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Chajęcka-Wierzchowska W, Zadernowska A, Łaniewska-Trokenheim Ł. Diversity of Antibiotic Resistance Genes inEnterococcusStrains Isolated from Ready-to-Eat Meat Products. J Food Sci 2016; 81:M2799-M2807. [DOI: 10.1111/1750-3841.13523] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/09/2016] [Accepted: 09/09/2016] [Indexed: 11/27/2022]
Affiliation(s)
- Wioleta Chajęcka-Wierzchowska
- Industrial and Food Microbiology, Faculty of Food Science; Univ. of Warmia and Mazury; Plac Cieszyński 1 10-726 Olsztyn Poland
| | - Anna Zadernowska
- Industrial and Food Microbiology, Faculty of Food Science; Univ. of Warmia and Mazury; Plac Cieszyński 1 10-726 Olsztyn Poland
| | - Łucja Łaniewska-Trokenheim
- Industrial and Food Microbiology, Faculty of Food Science; Univ. of Warmia and Mazury; Plac Cieszyński 1 10-726 Olsztyn Poland
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8
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Medeiros AW, Blaese Amorim D, Tavares M, de Moura TM, Franco AC, d'Azevedo PA, Frazzon J, Frazzon APG. Enterococcus species diversity in fecal samples of wild marine species as determined by real-time PCR. Can J Microbiol 2016; 63:129-136. [PMID: 27991828 DOI: 10.1139/cjm-2016-0427] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Analyses using culture-independent molecular techniques have improved our understanding of microbial composition. The aim of this work was to identify and quantify enterococci in fecal samples of wild marine species using real-time quantitative PCR. Seven Enterococcus species were examined in fecal DNA of South American fur seals (Arctocephalus australis), Subantarctic fur seals (Arctocephalus tropicalis), green turtles (Chelonia mydas), Magellanic penguins (Spheniscus magellanicus), snowy-crowned tern (Sterna trudeaui), white-backed stilt (Himantopus melanurus), white-chinned petrels (Procellaria aequinoctialis), red knot (Calidris canutus), and black-browed albatross (Thalassarche melanophris). All Enterococcus species evaluated were detected in all fecal samples of wild marine species, with a concentration ranging between 106 and 1012 copies/ng of total DNA. Differences in the enterococci distribution were observed. Enterococcus faecalis and Enterococcus mundtii were most abundant in marine mammals. Enterococcus faecalis was frequent in green turtle, Magellanic penguin, snowy-crowned tern, red knot, and black-browed albatross. Enterococcus hirae and Enterococcus gallinarum showed elevated occurrence in white-backed stilt, and Enterococcus faecium in white-chinned petrel. This study showed highest diversity of enterococci in feces of wild marine species than currently available data, and reinforced the use of culture-independent analysis to help us to enhance our understanding of enterococci in gastrointestinal tracts of wild marine species.
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Affiliation(s)
- Aline Weber Medeiros
- a Microbiology, Immunology, and Parasitology Department, Federal University of Rio Grande do Sul, Sarmento Leite, 500, CEP 90050-170, Porto Alegre, RS, Brazil
| | - Derek Blaese Amorim
- b Center for Coastal Studies, Limnology and Marine, Institute of Biosciences, Federal University of Rio Grande do Sul, Av. Tramandaí, 976, CEP 95625-000, Imbé, RS, Brazil
| | - Maurício Tavares
- b Center for Coastal Studies, Limnology and Marine, Institute of Biosciences, Federal University of Rio Grande do Sul, Av. Tramandaí, 976, CEP 95625-000, Imbé, RS, Brazil
| | - Tiane Martin de Moura
- c Department of Nutrition, Federal University of Pelotas, Rua Gomes Carneiro, 1 - Centro, CEP 96010-610, Pelotas, RS, Brazil
| | - Ana Claudia Franco
- a Microbiology, Immunology, and Parasitology Department, Federal University of Rio Grande do Sul, Sarmento Leite, 500, CEP 90050-170, Porto Alegre, RS, Brazil
| | - Pedro Alves d'Azevedo
- d Gram-positive Coccus Laboratory, Federal University of Health Sciences of Porto Alegre, Sarmento Leite, 245, CEP 90050-170, Porto Alegre, RS, Brazil
| | - Jeverson Frazzon
- e Food Science Institute, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500 - Campus do Vale - Prédio 443.212, CEP 91501-970, Porto Alegre, RS, Brazil
| | - Ana Paula Guedes Frazzon
- a Microbiology, Immunology, and Parasitology Department, Federal University of Rio Grande do Sul, Sarmento Leite, 500, CEP 90050-170, Porto Alegre, RS, Brazil
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9
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Virulence factors, antimicrobial resistance and biofilm formation in Enterococcus spp. isolated from retail shrimps. Lebensm Wiss Technol 2016. [DOI: 10.1016/j.lwt.2016.01.034] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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Prichula J, Pereira RI, Wachholz GR, Cardoso LA, Tolfo NCC, Santestevan NA, Medeiros AW, Tavares M, Frazzon J, d'Azevedo PA, Frazzon APG. Resistance to antimicrobial agents among enterococci isolated from fecal samples of wild marine species in the southern coast of Brazil. MARINE POLLUTION BULLETIN 2016; 105:51-57. [PMID: 26952995 DOI: 10.1016/j.marpolbul.2016.02.071] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 06/05/2023]
Abstract
The purpose of this study was to evaluate species distribution, antimicrobial resistance profiles, and presence of resistance genes in enterococci isolated from fecal samples of wild marine species, including seabirds (n=12), sea turtles (n=8), and mammals (n=3) found alive or dead in southern coast of Brazil. Enterococci were classified based on phenotypic and genotypic characteristics, tested for antibiotic susceptibility, and the presence of tet(S), tet(M), tet(L), mrsC, and erm(B) genes by PCR. Enterococcus faecalis and Enterococcus faecium were the most common species. Single (37.09%), double (25.80%), and multiple (16.12%) antibiotic resistance patterns were observed. Resistance to rifampicin occurred most frequently. The msrC, tet(M), and/or tet(L) genes were detected in 60.15%, 73.07%, and 23.07% of the resistant strains, respectively. In conclusion, the presence of antibiotic resistant strains in these species could be related to food web interactions and aquatic pollutants or linked to environmental resistome.
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Affiliation(s)
- Janira Prichula
- Microbiology, Immunology and Parasitology Department, Federal University of Rio Grande do Sul (UFRGS), Sarmento Leite 500, room 158, 90050-170, Porto Alegre, RS, Brazil; Gram-positive Coccus Laboratory, Federal University of Health Sciences of Porto Alegre (UFCSPA), Sarmento Leite 245, room 204, 90050-170, Porto Alegre, RS, Brazil
| | - Rebeca Inhoque Pereira
- Microbiology, Immunology and Parasitology Department, Federal University of Rio Grande do Sul (UFRGS), Sarmento Leite 500, room 158, 90050-170, Porto Alegre, RS, Brazil; Gram-positive Coccus Laboratory, Federal University of Health Sciences of Porto Alegre (UFCSPA), Sarmento Leite 245, room 204, 90050-170, Porto Alegre, RS, Brazil
| | - Guilherme Raffo Wachholz
- Gram-positive Coccus Laboratory, Federal University of Health Sciences of Porto Alegre (UFCSPA), Sarmento Leite 245, room 204, 90050-170, Porto Alegre, RS, Brazil
| | - Leonardo Almansa Cardoso
- Microbiology, Immunology and Parasitology Department, Federal University of Rio Grande do Sul (UFRGS), Sarmento Leite 500, room 158, 90050-170, Porto Alegre, RS, Brazil
| | - Neidimar Cezar Correa Tolfo
- Gram-positive Coccus Laboratory, Federal University of Health Sciences of Porto Alegre (UFCSPA), Sarmento Leite 245, room 204, 90050-170, Porto Alegre, RS, Brazil
| | - Naiara Aguiar Santestevan
- Microbiology, Immunology and Parasitology Department, Federal University of Rio Grande do Sul (UFRGS), Sarmento Leite 500, room 158, 90050-170, Porto Alegre, RS, Brazil
| | - Aline Weber Medeiros
- Microbiology, Immunology and Parasitology Department, Federal University of Rio Grande do Sul (UFRGS), Sarmento Leite 500, room 158, 90050-170, Porto Alegre, RS, Brazil
| | - Maurício Tavares
- Center for Coastal Studies, Limnology and Marine (CECLIMAR), Institute of Biosciences, UFRGS. Av. Tramandaí, 976, 95625-000, Imbé, RS, Brazil
| | - Jeverson Frazzon
- Food Science Institute, UFRGS, Av. Bento Gonçalves 9500 - Campus do Vale - Prédio 443.212, 91501-970, Porto Alegre, RS, Brazil
| | - Pedro Alves d'Azevedo
- Gram-positive Coccus Laboratory, Federal University of Health Sciences of Porto Alegre (UFCSPA), Sarmento Leite 245, room 204, 90050-170, Porto Alegre, RS, Brazil
| | - Ana Paula Guedes Frazzon
- Microbiology, Immunology and Parasitology Department, Federal University of Rio Grande do Sul (UFRGS), Sarmento Leite 500, room 158, 90050-170, Porto Alegre, RS, Brazil.
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11
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Nowakiewicz A, Ziółkowska G, Zięba P, Trościańczyk A, Banach T, Kowalski C. Modified 16S-23S rRNA intergenic region restriction endonuclease analysis for species identification of Enterococcus strains isolated from pigs, compared with identification using classical methods and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. J Med Microbiol 2015; 64:217-223. [PMID: 25587074 DOI: 10.1099/jmm.0.000008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fast and reliable identification of bacteria to at least the species level is currently the basis for correct diagnosis and appropriate treatment of infections. This is particularly important in the case of bacteria of the genus Enterococcus, whose resistance profile is often correlated with their species (e.g. resistance to vancomycin). In this study, we evaluated restriction endonuclease analysis of the 16S-23S rRNA gene intergenic transcribed spacer (ITS) region for species identification of Enterococcus. The utility of the method was compared with that of phenotypic methods [biochemical profile evaluation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)]. Identification was based on 21 Enterococcus reference strains, of the species E. faecalis, E. faecium, E. hirae, E. durans, E. casseliflavus, E. gallinarum, E. avium, E. cecorum and E. columbae, and 47 Enterococcus field strains isolated from pigs. Restriction endonuclease analysis of the ITS-PCR product using HinfI, RsaI and MboI, in the order specified, enabled species differentiation of the Enterococcus reference and field strains, and in the case of the latter, the results of species identification were identical (47/47) to those obtained by MALDI-TOF MS. Moreover, as a result of digestion with MboI, a unique restriction profile was also obtained for the strains (3/3) identified by MALDI-TOF MS as E. thailandicus. In our opinion, restriction endonuclease analysis of the 16S-23S rRNA gene ITS region of Enterococcus may be a simple and relatively fast (less than 4 h) alternative method for identifying the species occurring most frequently in humans and animals.
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Affiliation(s)
- Aneta Nowakiewicz
- University of Life Sciences, Faculty of Veterinary Medicine, Institute of Biological Bases of Animal Diseases, Sub-Department of Veterinary Microbiology, Akademicka 12, 20-033 Lublin, Poland
| | - Grażyna Ziółkowska
- University of Life Sciences, Faculty of Veterinary Medicine, Institute of Biological Bases of Animal Diseases, Sub-Department of Veterinary Microbiology, Akademicka 12, 20-033 Lublin, Poland
| | - Przemysław Zięba
- State Veterinary Laboratory, Droga Męczenników Majdanka 50, 20-325 Lublin, Poland
| | - Aleksandra Trościańczyk
- University of Life Sciences, Faculty of Veterinary Medicine, Institute of Biological Bases of Animal Diseases, Sub-Department of Veterinary Microbiology, Akademicka 12, 20-033 Lublin, Poland
| | - Tomasz Banach
- University of Life Sciences, Faculty of Veterinary Medicine, Department of Epizootiology and Clinic of Infectious Diseases, Głęboka 30, 20-612 Lublin, Poland
| | - Cezary Kowalski
- University of Life Sciences, Faculty of Veterinary Medicine, Department of Preclinical Veterinary Sciences, Sub-Department of Pharmacology, Akademicka 12, 20-033 Lublin, Poland
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12
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Burdychová R. Study of enterococci during cheese manufacture and ripening and evaluation of their role in tyramine production. ACTA UNIVERSITATIS AGRICULTURAE ET SILVICULTURAE MENDELIANAE BRUNENSIS 2014. [DOI: 10.11118/actaun200957050049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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13
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Castillo-Rojas G, Mazari-Hiríart M, Ponce de León S, Amieva-Fernández RI, Agis-Juárez RA, Huebner J, López-Vidal Y. Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships. PLoS One 2013; 8:e59491. [PMID: 23560050 PMCID: PMC3613387 DOI: 10.1371/journal.pone.0059491] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 02/14/2013] [Indexed: 11/26/2022] Open
Abstract
Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area) and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation), respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE). E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species.
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Affiliation(s)
- Gonzalo Castillo-Rojas
- Programa de Inmunología Molecular Microbiana, Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, México
| | - Marisa Mazari-Hiríart
- Laboratorio de Ecología Química, Instituto de Ecología, Universidad Nacional Autónoma de México, México City, México
| | - Sergio Ponce de León
- Subdirector de Servicios Paramédicos, Instituto Nacional de Ciencias Médicas y Nutrición “Salvador Zubirán”, México City, México
| | - Rosa I. Amieva-Fernández
- Programa de Inmunología Molecular Microbiana, Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, México
| | - Raúl A. Agis-Juárez
- Programa de Inmunología Molecular Microbiana, Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, México
| | - Johannes Huebner
- Division of Infectious Diseases, Department of Medicine, University Medical Center Freiburg, Freiburg, Germany
| | - Yolanda López-Vidal
- Programa de Inmunología Molecular Microbiana, Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, México
- * E-mail:
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Bae HS, Hou A. 23S rRNA gene-based enterococci community signatures in Lake Pontchartrain, Louisiana, USA, following urban runoff inputs after Hurricane Katrina. MICROBIAL ECOLOGY 2013; 65:289-301. [PMID: 23269456 DOI: 10.1007/s00248-012-0166-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 12/11/2012] [Indexed: 06/01/2023]
Abstract
Little is known about the impacts of fecal polluted urban runoff inputs on the structure of enterococci communities in estuarine waters. This study employed a 23S rRNA gene-based polymerase chain reaction (PCR) assay with newly designed genus-specific primers, Ent127F-Ent907R, to determine the possible impacts of Hurricane Katrina floodwaters via the 17th Street Canal discharge on the community structure of enterococci in Lake Pontchartrain. A total of 94 phylotypes were identified through the restriction fragment length polymorphism (RFLP) screening of 494 clones while only 8 phylotypes occurred among 88 cultivated isolates. Sequence analyses of representative phylotypes and their temporal and spatial distribution in the lake and the canal indicated the Katrina floodwater input introduced a large portion of Enterococcus flavescens, Enterococcus casseliflavus, and Enterococcus dispar into the lake; typical fecal groups Enterococcus faecium, Enterococcus durans, Enterococcus hirae, and Enterococcus mundtii were detected primarily in the floodwater-impacted waters. This study provides a global picture of enterococci in estuarine waters impacted by Hurricane Katrina-derived urban runoff. It also demonstrates the culture-independent PCR approach using 23S rRNA gene as a molecular marker could be a good alternative in ecological studies of enterococci in natural environments to overcome the limitation of conventional cultivation methods.
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Affiliation(s)
- Hee-Sung Bae
- Department of Environmental Sciences, School of Coast and Environment, Louisiana State University, Baton Rouge, LA 70803, USA
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Development of a DNA microarray for enterococcal species, virulence, and antibiotic resistance gene determinations among isolates from poultry. Appl Environ Microbiol 2011; 77:2625-33. [PMID: 21335389 DOI: 10.1128/aem.00263-11] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A DNA microarray (Enteroarray) was designed with probes targeting four species-specific taxonomic identifiers to discriminate among 18 different enterococcal species, while other probes were designed to identify 18 virulence factors and 174 antibiotic resistance genes. In total, 262 genes were utilized for rapid species identification of enterococcal isolates, while characterizing their virulence potential through the simultaneous identification of endogenous antibiotic resistance and virulence genes. Enterococcal isolates from broiler chicken farms were initially identified by using the API 20 Strep system, and the results were compared to those obtained with the taxonomic genes atpA, recA, pheS, and ddl represented on our microarray. Among the 171 isolates studied, five different enterococcal species were identified by using the API 20 Strep system: Enterococcus faecium, E. faecalis, E. durans, E. gallinarum, and E. avium. The Enteroarray detected the same species as API 20 Strep, as well as two more: E. casseliflavus and E. hirae. Species comparisons resulted in 15% (27 isolates) disagreement between the two methods among the five API 20 Strep identifiable species and 24% (42 isolates) disagreement when considering the seven Enteroarray identified species. The species specificity of key antibiotic and virulence genes identified by the Enteroarray were consistent with the literature adding further robustness to the redundant taxonomic probe data. Sequencing of the cpn60 gene further confirmed the complete accuracy of the microarray results. The new Enteroarray should prove to be a useful tool to accurately genotype strains of enterococci and assess their virulence potential.
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Colombo F, Borgo F, Fortina MG. Genotypic characterization of non starter lactic acid bacteria involved in the ripening of artisanal Bitto PDO cheese. J Basic Microbiol 2009; 49:521-30. [DOI: 10.1002/jobm.200800381] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Bacterial diversity of Darfiyeh, a Lebanese artisanal raw goat's milk cheese. Food Microbiol 2009; 26:645-52. [DOI: 10.1016/j.fm.2009.04.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 04/21/2009] [Accepted: 04/25/2009] [Indexed: 11/19/2022]
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18
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Polyphasic study of microbial communities of two Spanish farmhouse goats' milk cheeses from Sierra de Aracena. Food Microbiol 2009; 26:294-304. [DOI: 10.1016/j.fm.2008.12.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Revised: 12/09/2008] [Accepted: 12/21/2008] [Indexed: 11/17/2022]
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19
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Polyphasic approach to bacterial dynamics during the ripening of Spanish farmhouse cheese, using culture-dependent and -independent methods. Appl Environ Microbiol 2008; 74:5662-73. [PMID: 18658288 DOI: 10.1128/aem.00418-08] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We studied the dynamics of the microbial population during ripening of Cueva de la Magahá cheese using a combination of classical and molecular techniques. Samples taken during ripening of this Spanish goat's milk cheese in which Lactococcus lactis and Streptococcus thermophilus were used as starter cultures were analyzed. All bacterial isolates were clustered by using randomly amplified polymorphic DNA (RAPD) and identified by 16S rRNA gene sequencing, species-specific PCR, and multiplex PCR. Our results indicate that the majority of the 225 strains isolated and enumerated on solid media during the ripening period were nonstarter lactic acid bacteria, and Lactobacillus paracasei was the most abundant species. Other Lactobacillus species, such as Lactobacillus plantarum and Lactobacillus parabuchneri, were also detected at the beginning and end of ripening, respectively. Non-lactic-acid bacteria, mainly Kocuria and Staphylococcus strains, were also detected at the end of the ripening period. Microbial community dynamics determined by temporal temperature gradient gel electrophoresis provided a more precise estimate of the distribution of bacteria and enabled us to detect Lactobacillus curvatus and the starter bacteria S. thermophilus and L. lactis, which were not isolated. Surprisingly, the bacterium most frequently found using culture-dependent analysis, L. paracasei, was scarcely detected by this molecular approach. Finally, we studied the composition of the lactobacilli and their evolution by using length heterogeneity PCR.
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Serio A, Paparella A, Chaves-López C, Corsetti A, Suzzi G. Enterococcus populations in Pecorino Abruzzese cheese: biodiversity and safety aspects. J Food Prot 2007; 70:1561-8. [PMID: 17685326 DOI: 10.4315/0362-028x-70.7.1561] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The presence of enterococci in Pecorino Abruzzese cheese during ripening was evaluated. Counts were high, especially in fully ripened summer batches. Seventy strains were isolated and identified based on phenotypical and genotypical features as Enterococcus faecium (48.5%), Enterococcus faecalis (40%), and Enterococcus durans (11.5%), with the first species predominant in spring batches and the second predominant in summer batches. High biodiversity was revealed by random amplification of polymorphic DNA and a PCR assay, suggesting the presence of autochthonous strains. E. faecium isolates were the most resistant to the tested antibiotics, especially to erythromycin, chloramphenicol, and penicillin, but all strains were susceptible to vancomycin, as confirmed by the absence of vanA and vanB genes. The presence of some virulence determinants was investigated, revealing the diffusion of aggregation substance (asal) and gelatinase (gelE) genes in 37.5% of E. faecalis strains. However, none of the isolates produced gelatinase in vitro, suggesting the presence of silent genes. The virulence genes were absent in E. durans. Among E. faecium strains, only Lab 41/1 possessed gelE and asal, whose presence previously has been reported only in E. faecalis. Decarboxylating activity was revealed for phenylalanine (27% of the strains) and tyrosine (96%) but not histidine. The presence of a tyrosine decarboxylase-encoding gene was observed for all strains. A comparison of these results with those of previous studies of clinical and food isolates indicates that enterococci from Pecorino Abruzzese cheese have low pathogenic potential.
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Affiliation(s)
- Annalisa Serio
- Dipartimento di Scienze degli Alimenti, Università degli Studi di Teramo, Via C.R. Lerici, 1, 64023 Mosciano Stazione TE, Italy.
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Fortina MG, Ricci G, Borgo F, Manachini PL. Rapid identification of Enterococcus italicus by PCR with primers targeted to 16S rRNA gene. Lett Appl Microbiol 2007; 44:443-6. [PMID: 17397485 DOI: 10.1111/j.1472-765x.2006.02082.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To develop a species-specific PCR assay with primers targeted to 16S rRNA gene for the identification of Enterococcus italicus, a new species of Enterococcus, involved in the production of Italian cheeses. METHODS AND RESULTS The type strain of E. italicus (DSM 15952(T) - 16S rRNA gene accession no. AJ582753) and other strains of the species were subjected to a rapid identification by PCR using primer pairs located within the 16S rRNA gene. A species-specific PCR product of approximately 323 bp was obtained after amplification of all E. italicus strains tested. The specificity of the primers was validated with representatives of the most closely related genera and species and a number of other bacterial species. In addition, the technique enabled the recognition of E. italicus from cheeses. CONCLUSIONS The protocol was highly efficient and sensitive, enabling the identification of E. italicus from cheeses. SIGNIFICANCE AND IMPACT OF THE STUDY The species-specific PCR offers a reliable and rapid alternative to conventional phenotypic methods for the identification of E. italicus within the heterogeneous genus Enterococcus.
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Affiliation(s)
- M G Fortina
- Industrial Microbiology Section, Department of Food Science and Microbiology, University of Milan, Milan, Italy.
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Biavasco F, Foglia G, Paoletti C, Zandri G, Magi G, Guaglianone E, Sundsfjord A, Pruzzo C, Donelli G, Facinelli B. VanA-type enterococci from humans, animals, and food: species distribution, population structure, Tn1546 typing and location, and virulence determinants. Appl Environ Microbiol 2007; 73:3307-19. [PMID: 17351100 PMCID: PMC1907105 DOI: 10.1128/aem.02239-06] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
VanA-type human (n=69), animal (n=49), and food (n=36) glycopeptide-resistant enterococci (GRE) from different geographic areas were investigated to study their possible reservoirs and transmission routes. Pulsed-field gel electrophoresis (PFGE) revealed two small genetically related clusters, M39 (n=4) and M49 (n=13), representing Enterococcus faecium isolates from animal and human feces and from clinical and fecal human samples. Multilocus sequence typing showed that both belonged to the epidemic lineage of CC17. purK allele analysis of 28 selected isolates revealed that type 1 was prevalent in human strains (8/11) and types 6 and 3 (14/15) were prevalent in poultry (animals and meat). One hundred and five of the 154 VanA GRE isolates, encompassing different species, origins, and PFGE types, were examined for Tn1546 type and location (plasmid or chromosome) and the incidence of virulence determinants. Hybridization of S1- and I-CeuI-digested total DNA revealed a plasmid location in 98% of the isolates. Human intestinal and animal E. faecium isolates bore large (>150 kb) vanA plasmids. Results of PCR-restriction fragment length polymorphism and sequencing showed the presence of prototype Tn1546 in 80% of strains and the G-to-T mutation at position 8234 in three human intestinal and two pork E. faecium isolates. There were no significant associations (P>0.5) between Tn1546 type and GRE source or enterococcal species. Virulence determinants were detected in all reservoirs but were significantly more frequent (P<0.02) among clinical strains. Multiple determinants were found in clinical and meat Enterococcus faecalis isolates. The presence of indistinguishable vanA elements (mostly plasmid borne) and virulence determinants in different species and PFGE-diverse populations in the presence of host-specific purK housekeeping genes suggested that all GRE might be potential reservoirs of resistance determinants and virulence traits transferable to human-adapted clusters.
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Affiliation(s)
- F Biavasco
- Institute of Microbiology and Biomedical Sciences, Polytechnic University of Marche, Via Ranieri, Monte d'Ago, 60131 Ancona, Italy.
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PISANO MBARBARA, FADDA MELISABETTA, DEPLANO MAURA, CORDA ARIANNA, COSENTINO SOFIA. Microbiological and chemical characterization of Fiore Sardo, a traditional Sardinian cheese made from ewe's milk. INT J DAIRY TECHNOL 2006. [DOI: 10.1111/j.1471-0307.2006.00260.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Jurkovic D, Krizková L, Dusinský R, Belicová A, Sojka M, Krajcovic J, Ebringer L. Identification and characterization of enterococci from bryndza cheese. Lett Appl Microbiol 2006; 42:553-9. [PMID: 16706891 DOI: 10.1111/j.1472-765x.2006.01918.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To identify enterococci isolated from sheep milk cheese--bryndza, and to compare differences in the composition of enterococcal microflora affected by the season, and to evaluate the potential presence of vancomycin resistance and virulence determinants. METHODS AND RESULTS Bacterial strains were isolated during analysis of bryndza cheese and identified on the genus and species level by phenotypic methods and with commercial biochemical sets. The identification of the species, Enterococcus faecium, Ent. durans and Ent. faecalis, was confirmed by PCR using species-specific primers for ddl genes. PCR was also used for assessment of presence of vanA and vanB genes and virulence determinants gelE, agg and cytolysin genes namely: cylL(L), cylL(S), cylM, cylB and cylA. Among 308 Enterococcus sp. strains, 177 isolates were proved to be Ent. faecium, 59 to be Ent. durans and 41 to be Ent. faecalis. Vancomycin resistance genes vanA and vanB were not detected. Agar plate testing confirmed their absence. Gene gelE, however, was found in 20 Ent. faecalis isolates, but only 13 of them showed gelatinase-positive phenotype. Seven isolates had five cytolysin genes, but none of the isolates exhibited a positive haemolytic phenotype. Four isolates possessed the agg gene. The prevalence of Ent. faecium species was highest in samples from the winter season harvest. CONCLUSIONS Ent. faecium is the dominant enterococcal species in bryndza cheese and the most prevalent in the winter season product. None of the Enterococcus sp. strains was proved to have vanA or vanB genes and the vancomycin resistance. SIGNIFICANCE AND IMPACT OF THE STUDY To our knowledge, this is the first report of enterococcal microflora in bryndza cheese and its evaluation for the presence of vanA and vanB genes as well as virulence determinants.
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Affiliation(s)
- D Jurkovic
- Institute of Cell Biology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovak Republic
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Arias CA, Robredo B, Singh KV, Torres C, Panesso D, Murray BE. Rapid identification of Enterococcus hirae and Enterococcus durans by PCR and detection of a homologue of the E. hirae mur-2 Gene in E. durans. J Clin Microbiol 2006; 44:1567-70. [PMID: 16597896 PMCID: PMC1448630 DOI: 10.1128/jcm.44.4.1567-1570.2006] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2005] [Accepted: 02/09/2006] [Indexed: 11/20/2022] Open
Abstract
During an evaluation of PCR for identification of isolates of Enterococcus hirae, a homologue with 82% identity to E. hirae mur-2 was identified in Enterococcus durans and was named mur-2(ed). PCR using primers for two genes (copY and murG) of E. hirae strains showed amplification with E. hirae strains only. PCR (under high-stringency conditions) with primers for the mur-2(ed) gene gave the expected amplification product only with E. durans strains. A combination of murG and mur-2(ed) primers in a multiplex PCR assay differentiated E. hirae from E. durans in all cases. PCR using these primers appears to be a rapid alternative for identification of E. hirae and E. durans isolates.
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Affiliation(s)
- Cesar A Arias
- Center for the Study of Emerging and Reemerging Pathogens, University of Texas Medical School, Houston, TX 77030, USA
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Phenotypic and genotypic identification of lactic acid bacteria isolated from a small-scale facility producing traditional dry sausages. Food Microbiol 2005. [DOI: 10.1016/j.fm.2004.11.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abriouel H, Lucas R, Ben Omar N, Valdivia E, Maqueda M, Martínez-Cañamero M, Gálvez A. Enterocin AS-48RJ: a variant of enterocin AS-48 chromosomally encoded by Enterococcus faecium RJ16 isolated from food. Syst Appl Microbiol 2005; 28:383-97. [PMID: 16094865 DOI: 10.1016/j.syapm.2005.01.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The bacteriocinogenic strain RJ16 isolated from goat cheese has been identified as Enterococcusfaecium by species-specific PCR, DNA-rRNA hybridization and rDNA sequencing. Purified bacteriocin from strain RJ16 is a carboxypeptidase A-resistant peptide with a molecular mass (7125 Da) very close to the cyclic peptide enterocin AS-48. Bacteriocin from strain RJ16 and AS-48 show identical antibacterial spectra, although the former is slightly less active on strains of Listeria monocytogenes and Bacillus cereus. Producer strains show cross-immunity. PCR amplification of total DNA from strain RJ16 with primers for the AS-48 structural gene and sequencing of the amplified fragment revealed an almost identical sequence (99.5%), except for a single mutation that predicts the change of Glu residue at position 20 of AS-48 to Val. Therefore, bacteriocin produced by E. faecium RJ16 should be considered a variant of AS-48, which we call AS-48RJ. PCR amplification revealed that strain RJ16 contains the complete as-48. gene cluster. Hybridization with probes for as-48 gene cluster revealed a chromosomal location of as-48 genes in strain RJ16, being the first example of a chromosomal location of this bacteriocin trait. Strain RJ16 produced enzymes of interest in food processing (esterase, esterase lipase and phytase activities), and did not decarboxylate amino acids precursors for biogenic amines. Strain RJ16 did not exhibit haemolytic or gelatinase activities, and PCR amplification revealed the lack of genes encoding for known virulence determinants (aggregation substance, collagen adhesin, enterococcal surface protein, endocarditis antigens, as well as haemolysin and gelatinase production). Strain RJ16 was resistant to ciprofloxacin (MIC > 2 mgl(-1)) and levofloxacin (MIC > 4 mgl(-1)) and showed intermediate resistance to nitrofurantoin and erythromycin, but was sensitive to ampicillin, penicillin, streptomycin, gentamicin, rifampicin, chloramphenicol, tetracycline, quinupristin/dalfopristin, vancomycin and teicoplanin. Altogether, results from this study suggest that this broad-spectrum bacteriocin-producing strain may have a potential use in food preservation.
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Affiliation(s)
- Hikmate Abriouel
- Area de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071-Jaén, Spain
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Naser SM, Thompson FL, Hoste B, Gevers D, Dawyndt P, Vancanneyt M, Swings J. Application of multilocus sequence analysis (MLSA) for rapid identification of Enterococcus species based on rpoA and pheS genes. Microbiology (Reading) 2005; 151:2141-2150. [PMID: 16000705 DOI: 10.1099/mic.0.27840-0] [Citation(s) in RCA: 304] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aim of this study was to evaluate the use of RNA polymeraseαsubunit (rpoA) and phenylalanyl-tRNA synthase (pheS) gene sequences as species identification tools for enterococci. Ninety-six representative strains comprising all currently recognizedEnterococcusspecies were examined.rpoAgene sequences generated a robust classification into species groups similar to the one based on 16S rRNA gene sequence analysis. On the other hand, thepheSgene is a fast-evolving clock even better suited for species delineation than therpoAgene, but not for recognition of species groups withinEnterococcusas determined by bothrpoAand 16S rRNA genes. All enterococcal species were clearly differentiated on the basis of theirrpoAandpheSsequences. Evaluation of intraspecies variation showed that bothrpoAandpheSgenes have a high degree of homogeneity among strains of the same species. Strains of the same enterococcal species have at least 99 %rpoAand 97 %pheSgene sequence similarity, whereas, different enterococcal species have at maximum 97 %rpoAand 86 %pheSgene sequence similarity. It was concluded that both genes can be used as reliable tools for identification of clinical and environmental species ofEnterococcusand are efficient screening methods for the detection of novel species. The sequence data obtained in this study were compared to the availableatpAand 16S rRNA gene sequences. The MLSA approach toEnterococcustaxonomy provides portable, highly reproducible data with lower costs for rapid identification of all enterococcal species.
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Affiliation(s)
- Sabri M Naser
- BCCM/LMG Bacteria Collection, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
- Laboratory of Microbiology, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
| | - Fabiano L Thompson
- BCCM/LMG Bacteria Collection, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
| | - Bart Hoste
- BCCM/LMG Bacteria Collection, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
| | - Dirk Gevers
- Bioinformatics and Evolutionary Genomics, Ghent University/VIB, Technologiepark 927, Ghent 9052, Belgium
- Laboratory of Microbiology, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
| | - Peter Dawyndt
- Laboratory of Microbiology, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
| | - Marc Vancanneyt
- BCCM/LMG Bacteria Collection, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
| | - Jean Swings
- BCCM/LMG Bacteria Collection, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
- Laboratory of Microbiology, Ghent University, K. L. Ledeganckstraat 35, Ghent 9000, Belgium
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Marino M, Maifreni M, Rondinini G. Microbiological characterization of artisanal Montasio cheese: analysis of its indigenous lactic acid bacteria. FEMS Microbiol Lett 2004; 229:133-40. [PMID: 14659553 DOI: 10.1016/s0378-1097(03)00816-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
The aim of this study was to investigate the dynamics of the microflora during Montasio cheese ripening, with specific reference to some characteristics of biotechnological interest. Nine batches of Montasio cheese produced in different plants were analyzed. Streptococcus thermophilus was the predominant species throughout the whole ripening period of Montasio cheese. Enterococci were also frequently present. This microbial group resulted probably from milk, and its proportion decreased rapidly during ripening. The most acidifying microbial species was S. thermophilus, while the most proteolytic strains belonged to the genera Enterococcus. A high degree of phenotypic diversity occurred within the microbial species.
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Affiliation(s)
- Marilena Marino
- Dipartimento di Scienze degli Alimenti, Università degli Studi di Udine, 33100 Udine, Italy.
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Domig KJ, Mayer HK, Kneifel W. Methods used for the isolation, enumeration, characterisation and identification of Enterococcus spp. Int J Food Microbiol 2003; 88:165-88. [PMID: 14596988 DOI: 10.1016/s0168-1605(03)00178-8] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This paper reviews the methodology applied for the identification and characterisation of enterococci and covers phenotypic, genotypic and phylogenetic techniques. Although conventional phenotypic typing schemes are useful for rapid and simple identification of enterococcal species for routine applications, other methods like standardised sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), multilocus enzyme electrophoresis (MLEE), antimicrobial susceptibility testing, serotyping, pyrolysis mass spectrometry (pyMS) and vibrational spectroscopic methods allow a more in-depth characterisation of enterococci. Many of the recently described enterococcal species exhibit deviations from hitherto so-called classical enterococci with regard to their phenotypical properties. Therefore, genotypic methods have to be used to clarify their possible assignment to the genus Enterococcus. In this review, special emphasis is given on recently developed polymerase chain reaction (PCR)-based typing methods such as random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), specific and random amplification (SARA) and modifications of PCR-ribotyping as well as pulsed-field gel electrophoresis (PFGE) and partial sequence analysis. The use of PCR and probes for genus and species identification of enterococci is also considered like the application of sequence data of conserved DNA regions (e.g., ribosomal ribonucleic acid (rRNA) genes) in the case of species identification.
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Affiliation(s)
- Konrad J Domig
- Department of Dairy Research and Bacteriology, University of Natural Resources and Applied Life Sciences, Gregor Mendel Strasse 33, 1180 Vienna, Austria
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