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Khusro A, Aarti C. Metabolic heterogeneity and techno-functional attributes of fermented foods-associated coagulase-negative staphylococci. Food Microbiol 2022; 105:104028. [DOI: 10.1016/j.fm.2022.104028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 03/13/2022] [Accepted: 03/13/2022] [Indexed: 01/03/2023]
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2
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Kebede TG, Dube S, Nindi MM. Application of mesoporous nanofibers as sorbent for removal of veterinary drugs from water systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:140282. [PMID: 32806356 DOI: 10.1016/j.scitotenv.2020.140282] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
A novel environmentally benign method was developed for the simultaneous removal of sulphonamides and multiclass class of veterinary drugs using mesoporous nanofibers. Processing parameters which affect the removal efficiency, such as pH, initial analyte concentration, adsorbent dosage and contact time were studied. An optimised method was applied to a real wastewater samples collected from Daspoort Wastewater Treatment Plant (WWTP), South Africa. Under optimum conditions, the removal efficiency of veterinary drugs from effluent and influent ranged from 35.24-94.57 ± 0.24 and 31.71-76.91 ± 0.65 mg g-1, respectively. The surface area, cumulative volume of pores and average pore diameter of the nanofibers were determined as 2402.62 ± 13.62 m2 g-1, 2.04 cm3 g-1 and 3.39 nm, respectively. The maximum adsorption capacity was ranged from 166 to 1000 mg g-1. The adsorption kinetics obeyed the pseudo-second-order rate equation suggesting that particle diffusion was the rate-limiting mechanism for adsorption of veterinary drugs on electrospun nanofibers.
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Affiliation(s)
- Temesgen Girma Kebede
- Department of Chemistry, The Science Campus, University of South Africa, Corner Christian de Wet and Pioneer avenue, Florida 1709, South Africa.
| | - Simiso Dube
- Department of Chemistry, The Science Campus, University of South Africa, Corner Christian de Wet and Pioneer avenue, Florida 1709, South Africa
| | - Mathew Muzi Nindi
- Department of Chemistry, The Science Campus, University of South Africa, Corner Christian de Wet and Pioneer avenue, Florida 1709, South Africa
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Lee S, Hwang J, Kim J, Lee J, Kim HC, Rhim H, Han JI. Biofilm production of coagulase-negative staphylococci isolated from rescued wild animals in the Republic of Korea. Acta Vet Scand 2019; 61:50. [PMID: 31651349 PMCID: PMC6814046 DOI: 10.1186/s13028-019-0485-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Accepted: 10/17/2019] [Indexed: 12/16/2022] Open
Abstract
Biofilm production is a well-known causative factor of catheter- and medical device-related sepsis. Its high prevalence in coagulase-negative staphylococci (CoNS) has recently been reported. Information on biofilm production in CoNS isolated from wild animals is lacking. Herein, we studied the biofilm formation capabilities of CoNS isolated from rescued wild animals in the Republic of Korea. Swab samples were collected from the conjunctiva, nasal cavity, perianal area, and rectum for mammals while the sampling was done from the conjunctiva, oral mucosa, pericloacal area, and cloaca for birds. Isolation of CoNS was based on morphological and biochemical analyses along with molecular typing. Biofilm production was analyzed using 96-well plate based quantitative adherence assays. The studies demonstrated that CoNS of mammalian origin have higher biofilm-producing ability (70.4%) than the isolates from birds (62.5%). In particular, all methicillin-resistant (MR) CoNS isolated from mammals were capable of biofilm formation while only 63.3% of MR CoNS isolated from birds could produce biofilms. The MR CoNS isolated from mammals also had a significantly higher ability to form biofilms (100%) than methicillin susceptible CoNS (60.0%) than those isolates from birds. The findings show that wild animals may act as reservoirs as well as possible transmitters of biofilm-mediated antibiotic resistant genes.
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Ouoba LII, Vouidibio Mbozo AB, Anyogu A, Obioha PI, Lingani-Sawadogo H, Sutherland JP, Jespersen L, Ghoddusi HB. Environmental heterogeneity of Staphylococcus species from alkaline fermented foods and associated toxins and antimicrobial resistance genetic elements. Int J Food Microbiol 2019; 311:108356. [PMID: 31670141 DOI: 10.1016/j.ijfoodmicro.2019.108356] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 08/31/2019] [Accepted: 09/06/2019] [Indexed: 12/12/2022]
Abstract
Different samples of three products including Bikalga and Soumbala from Burkina Faso (West Africa) and Ntoba Mbodi from Congo-Brazzaville (Central Africa) were evaluated. The bacteria (400) were phenotyped and genotypically characterized by Rep-PCR, PFGE, 16S rRNA and rpoB gene sequencing and spa typing. Their PFGE profiles were compared with those of 12,000 isolates in the Center for Disease Control (CDC, USA) database. They were screened for the production of enterotoxins, susceptibility to 19 antimicrobials, presence of 12 staphylococcal toxin and 38 AMR genes and the ability to transfer erythromycin and tetracycline resistance genes to Enterococcus faecalis JH2-2. Fifteen coagulase negative (CoNS) and positive (CoPS) species characterized by 25 Rep-PCR/PFGE clusters were identified: Staphylococcus arlettae, S. aureus, S. cohnii, S. epidermidis, S. gallinarum, S. haemolyticus, S. hominis, S. pasteuri, S. condimenti, S. piscifermentans, S. saprophyticus, S. sciuri, S. simulans, S. warneri and Macrococcus caseolyticus. Five species were specific to Soumbala, four to Bikalga and four to Ntoba Mbodi. Two clusters of S. gallinarum and three of S. sciuri were particular to Burkina Faso. The S. aureus isolates exhibited a spa type t355 and their PFGE profiles did not match any in the CDC database. Bacteria from the same cluster displayed similar AMR and toxin phenotypes and genotypes, whereas clusters peculiar to a product or a location generated distinct profiles. The toxin genes screened were not detected and the bacteria did not produce the staphylococcal enterotoxins A, B, C and D. AMR genes including blazA, cat501, dfr(A), dfr(G), mecA, mecA1, msr(A) and tet(K) were identified in CoNS and CoPS. Conjugation experiments produced JH2-2 isolates that acquired resistance to erythromycin and tetracycline, but no gene transfer was revealed by PCR. The investigation of the heterogeneity of Staphylococcus species from alkaline fermented foods, their relationship with clinical and environmental isolates and their safety in relation to antimicrobial resistance (AMR) and toxin production is anticipated to contribute to determining the importance of staphylococci in alkaline fermented foods, especially in relation to the safety of the consumers.
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Affiliation(s)
- L Irène I Ouoba
- Microbiology Research Unit, School of Human Sciences, London Metropolitan University, UK; Ouoba-Consulting, London, UK.
| | | | - Amarachukwu Anyogu
- Department of Life Sciences, Faculty of Science and Technology, University of Westminster, London, UK
| | - Promiselynda I Obioha
- Microbiology Research Unit, School of Human Sciences, London Metropolitan University, UK
| | | | - Jane P Sutherland
- Microbiology Research Unit, School of Human Sciences, London Metropolitan University, UK
| | - Lene Jespersen
- Microbial Ecology and Food Fermentation, Faculty of Sciences, University of Copenhagen, Frederiskberg, Denmark
| | - Hamid B Ghoddusi
- Microbiology Research Unit, School of Human Sciences, London Metropolitan University, UK
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Kebede TG, Dube S, Nindi MM. Characterisation of water-soluble protein powder and optimisation of process parameters for the removal of sulphonamides from wastewater. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:21450-21462. [PMID: 31127520 DOI: 10.1007/s11356-019-05272-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 04/24/2019] [Indexed: 06/09/2023]
Abstract
A valuable method for the efficient removal of sulphonamides from wastewater using protein powder extracted from the seeds of Moringa stenopetala is presented in this study. The surface morphology, crystallinity and functional groups of protein powder were characterised by SEM, XRD, FTIR and Raman spectrometry. Parameters that affect the removal of sulphonamides, such as concentration, the adsorbent dosage and pH, were optimised. The method was applied to a real wastewater sample collected from the Daspoort Wastewater Treatment Plant located in Pretoria, South Africa. The percentage removal under optimum conditions was observed to be 86.4 to 95.1% for the aqueous solution of a mixture of standards and from 83.0 to 90.5% and 75.2 to 87.7 % for the effluent and influent wastewater samples respectively. Therefore, proteins extracted from Moringa stenopetala seeds demonstrated to be effective and environmentally friendly material for possible application in water treatment in general and wastewater treatment in particular.
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Affiliation(s)
- Temesgen Girma Kebede
- Department of Chemistry, The Science Campus, University of South Africa, Corner Christian de Wet and Pioneer Avenue, Florida, 1709, South Africa
| | - Simiso Dube
- Department of Chemistry, The Science Campus, University of South Africa, Corner Christian de Wet and Pioneer Avenue, Florida, 1709, South Africa.
| | - Mathew Muzi Nindi
- Department of Chemistry, The Science Campus, University of South Africa, Corner Christian de Wet and Pioneer Avenue, Florida, 1709, South Africa
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Leroy S, Christieans S, Talon R. Tetracycline Gene Transfer in Staphylococcus xylosus in situ During Sausage Fermentation. Front Microbiol 2019; 10:392. [PMID: 30894841 PMCID: PMC6414713 DOI: 10.3389/fmicb.2019.00392] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 02/13/2019] [Indexed: 11/25/2022] Open
Abstract
The presence of determinants of resistance to antibiotics can constitute a possible safety hazard in coagulase-negative staphylococci (CNS), which are widely present in food of animal origin. Among CNS, S. xylosus is a species frequently isolated from fermented meat products. Resistance to tetracycline was found to be one of the most distributed resistances occurring in S. xylosus strains isolated from fermented sausages. We evaluated the transfer of tetracycline resistance in vitro and in situ between S. xylosus strains. We selected three strains isolated from dry fermented sausages, resistant to tetracycline but not to minocycline, their resistance occurring by a mechanism of active efflux encoded by the tetK gene. Only one strain was able to transfer its tetracycline resistance to a recipient strain initially susceptible and plasmid-free using a filter mating procedure. Transfer of tetracycline resistance was observed at very low frequencies of 3.4 × 10−9 per recipient. To further investigate the transferability of this tetracycline resistance, the donor and recipient strains were tested in pilot-scale fermented sausage production. This transfer was possible but at a low rate, 1.4 × 10−7, and only under conditions of a high inoculation level of 108 CFU/g of meat. The tetK gene is located on a small mobilizable plasmid close to Staphylococcus aureus pT181 plasmid. In conclusion, the transfer of tetracycline resistance between strains of S. xylosus is possible, but at a really low frequency in vitro and in situ in fermented sausages. Even if this represents a very moderate risk, it should be taken into account as required by the European approach of Qualified Presumption of Safety (QPS) and AFSSA safety recommendations, advising that strains used as starter cultures should not carry any transferable antibiotic resistance.
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Affiliation(s)
- Sabine Leroy
- Université Clermont Auvergne, INRA, MEDiS, Clermont-Ferrand, France
| | | | - Régine Talon
- Université Clermont Auvergne, INRA, MEDiS, Clermont-Ferrand, France
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Bulajic S, Colovic S, Misic D, Djordjevic J, Savic-Radovanovic R, Asanin J, Ledina T. Enterotoxin production and antimicrobial susceptibility in Staphylococci isolated from traditional raw milk cheeses in Serbia. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2017; 52:864-870. [PMID: 28949803 DOI: 10.1080/03601234.2017.1361764] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
This study was undertaken to determine the prevalence of coagulase positive staphylococci (CPS) by examining a total of 71 raw milk cheeses. Additionally, enterotoxigenicity, antimicrobial susceptibility and the presence of mecA and mecC genes in the staphylococcal isolates were investigated. The isolation and enumeration procedure of CPS followed the International Organization for Standardization (ISO) standard. The presumptive staphylococci were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using the VITEK MS system. VIDAS® Staph enterotoxin II assay was used for the detection of classical enterotoxins. Antimicrobial susceptibility testing (AST) was accomplished performing the disk diffusion method. All suspected methicillin resistant staphylococci were investigated for the presence of mecA and mecC genes by PCR assay. A high prevalence (87.32%) of CPS was detected in the cheeses at contamination levels up to 5.58 log CFU g-1. Among 47 staphylococcal isolates screened for enterotoxin production, only one isolate, identified as S. hyicus, was confirmed as being enterotoxigenic. Resistance to penicillin (63.70%) was the most common resistance among the tested Staphylococcus aureus isolates. The dominant phenotypic resistance patterns in coagulase negative staphylococci (CNS) were resistance to ofloxacin and fusidic acid. All CNS isolates were susceptible to the clinically important antibiotics clindamycin, chloramphenicol, gentamicin, linezolid, rifampicin and trimethoprim-sulfamethoxazole. The mecA and mecC genes were not detected. To the best of our knowledge, this is the first study concerning evaluation of the presence of methicillin resistant staphylococci (MRS) in dairy products in Serbia.
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Affiliation(s)
- Snezana Bulajic
- a Faculty of Veterinary Medicine, Department of Food Hygiene and Technology , University of Belgrade , Bulevar Oslobodjenja 18, Belgrade , Serbia
| | - Svetlana Colovic
- b Department of Sanitary Microbiology , Institute of Public Health of Belgrade , Bulevar Despota Stefana 54a, Belgrade , Serbia
| | - Dusan Misic
- c Faculty of Veterinary Medicine, Department of Microbiology and Immunology , University of Belgrade , Bulevar Oslobodjenja 18, Belgrade , Serbia
| | - Jasna Djordjevic
- a Faculty of Veterinary Medicine, Department of Food Hygiene and Technology , University of Belgrade , Bulevar Oslobodjenja 18, Belgrade , Serbia
| | - Radoslava Savic-Radovanovic
- a Faculty of Veterinary Medicine, Department of Food Hygiene and Technology , University of Belgrade , Bulevar Oslobodjenja 18, Belgrade , Serbia
| | - Jelena Asanin
- c Faculty of Veterinary Medicine, Department of Microbiology and Immunology , University of Belgrade , Bulevar Oslobodjenja 18, Belgrade , Serbia
| | - Tijana Ledina
- a Faculty of Veterinary Medicine, Department of Food Hygiene and Technology , University of Belgrade , Bulevar Oslobodjenja 18, Belgrade , Serbia
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Štšepetova J, Taelma H, Smidt I, Hütt P, Lapp E, Aotäht E, Mändar R. Assessment of phenotypic and genotypic antibiotic susceptibility of vaginalLactobacillussp. J Appl Microbiol 2017; 123:524-534. [DOI: 10.1111/jam.13497] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 05/02/2017] [Accepted: 05/19/2017] [Indexed: 12/12/2022]
Affiliation(s)
- J. Štšepetova
- Department of Microbiology; Institute of Biomedicine and Translational Medicine; University of Tartu; Tartu Estonia
- Competence Centre on Health Technologies; Tartu Estonia
| | - H. Taelma
- Department of Microbiology; Institute of Biomedicine and Translational Medicine; University of Tartu; Tartu Estonia
| | - I. Smidt
- Department of Microbiology; Institute of Biomedicine and Translational Medicine; University of Tartu; Tartu Estonia
- Competence Centre on Health Technologies; Tartu Estonia
| | - P. Hütt
- Department of Microbiology; Institute of Biomedicine and Translational Medicine; University of Tartu; Tartu Estonia
| | - E. Lapp
- Department of Microbiology; Institute of Biomedicine and Translational Medicine; University of Tartu; Tartu Estonia
| | - E. Aotäht
- Tartu Health Care Colleges; Tartu Estonia
| | - R. Mändar
- Department of Microbiology; Institute of Biomedicine and Translational Medicine; University of Tartu; Tartu Estonia
- Competence Centre on Health Technologies; Tartu Estonia
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A Novel erm(44) Gene Variant from a Human Staphylococcus saprophyticus Isolate Confers Resistance to Macrolides and Lincosamides but Not Streptogramins. Antimicrob Agents Chemother 2016; 61:AAC.01655-16. [PMID: 27799208 DOI: 10.1128/aac.01655-16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 10/23/2016] [Indexed: 01/30/2023] Open
Abstract
A novel erm(44) gene variant, erm(44)v, has been identified by whole-genome sequencing in a Staphylococcus saprophyticus isolate from the skin of a healthy person. It has the particularity to confer resistance to macrolides and lincosamides but not to streptogramin B when expressed in S. aureus The erm(44)v gene resides on a 19,400-bp genomic island which contains phage-associated proteins and is integrated into the chromosome of S. saprophyticus.
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Jeong DW, Lee B, Her JY, Lee KG, Lee JH. Safety and technological characterization of coagulase-negative staphylococci isolates from traditional Korean fermented soybean foods for starter development. Int J Food Microbiol 2016; 236:9-16. [PMID: 27427871 DOI: 10.1016/j.ijfoodmicro.2016.07.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 06/10/2016] [Accepted: 07/09/2016] [Indexed: 12/18/2022]
Abstract
To select starters for the production of meju and doenjang, traditional Korean fermented soybean foods, we assessed the safety and technological properties of their predominant isolates, Staphylococcus saprophyticus, Staphylococcus succinus and Staphylococcus xylosus. Phenotypic antibiotic resistance, hemolysis and biofilm formation were strain-specific. None of the S. succinus isolates exhibited antibiotic resistance or hemolytic activities. Thirty-three selected strains, identified through safety assessments of 81 coagulase-negative staphylococci (CNS) isolates, produced cadaverine, putrescine, and tyramine, but not histamine in the laboratory setting. The production of these three biogenic amines may, however, be insignificant considering the high levels of tyramine produced by the control, Enterococcus faecalis. The 33 CNS strains could grow on tryptic soy agar containing 21% NaCl (w/v), exhibited acid producing activity at 15% NaCl, and expressed strain-specific protease and lipase activities. S. succinus 14BME1, the selected starter candidate, produced significant amounts of benzeneacetic acid, 2,3-butanediol, trimethylpyrazine, and tetramethylpyrazine through soybean fermentation.
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Affiliation(s)
- Do-Won Jeong
- Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Republic of Korea
| | - Bitnara Lee
- Department of Food Science and Biotechnology, Kyonggi University, Suwon 16227, Republic of Korea
| | - Jae-Young Her
- Department of Food Science and Biotechnology, Dongguk University, Ilsan 10326, Republic of Korea
| | - Kwang-Geun Lee
- Department of Food Science and Biotechnology, Dongguk University, Ilsan 10326, Republic of Korea
| | - Jong-Hoon Lee
- Department of Food Science and Biotechnology, Kyonggi University, Suwon 16227, Republic of Korea.
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Regecová I, Pipová M, Jevinová P, Kmet’ V, Výrostková J, Sopková D. Antimicrobial Resistance of Coagulase-negative Species of Staphylococci Isolated from the Meat of Wild Pheasants (Phasianus Colchicus). ITALIAN JOURNAL OF ANIMAL SCIENCE 2016. [DOI: 10.4081/ijas.2014.3476] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Species Diversity and Pheno- and Genotypic Antibiotic Resistance Patterns of Staphylococci Isolated from Retail Ground Meats. J Food Sci 2015; 80:M1291-8. [DOI: 10.1111/1750-3841.12893] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 03/27/2015] [Indexed: 11/26/2022]
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New shuttle vector-based expression system to generate polyhistidine-tagged fusion proteins in Staphylococcus aureus and Escherichia coli. Appl Environ Microbiol 2015; 81:3243-54. [PMID: 25747000 DOI: 10.1128/aem.03803-14] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 02/25/2015] [Indexed: 01/01/2023] Open
Abstract
Four Staphylococcus aureus-Escherichia coli shuttle vectors were constructed for gene expression and production of tagged fusion proteins. Vectors pBUS1-HC and pTSSCm have no promoter upstream of the multiple cloning site (MCS), and this allows study of genes under the control of their native promoters, and pBUS1-Pcap-HC and pTSSCm-Pcap contain the strong constitutive promoter of S. aureus type 1 capsule gene 1A (Pcap) upstream of a novel MCS harboring codons for the peptide tag Arg-Gly-Ser-hexa-His (rgs-his6). All plasmids contained the backbone derived from pBUS1, including the E. coli origin ColE1, five copies of terminator rrnB T1, and tetracycline resistance marker tet(L) for S. aureus and E. coli. The minimum pAMα1 replicon from pBUS1 was improved through either complementation with the single-strand origin oriL from pUB110 (pBUS1-HC and pBUS1-Pcap-HC) or substitution with a pT181-family replicon (pTSSCm and pTSSCm-Pcap). The new constructs displayed increased plasmid yield and segregational stability in S. aureus. Furthermore, pBUS1-Pcap-HC and pTSSCm-Pcap offer the potential to generate C-terminal RGS-His6 translational fusions of cloned genes using simple molecular manipulation. BcgI-induced DNA excision followed by religation converts the TGA stop codon of the MCS into a TGC codon and links the rgs-his6 codons to the 3' end of the target gene. The generation of the rgs-his6 codon-fusion, gene expression, and protein purification were demonstrated in both S. aureus and E. coli using the macrolide-lincosamide-streptogramin B resistance gene erm(44) inserted downstream of Pcap. The new His tag expression system represents a helpful tool for the direct analysis of target gene function in staphylococcal cells.
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Regina VR, Lokanathan AR, Modrzyński JJ, Sutherland DS, Meyer RL. Surface physicochemistry and ionic strength affects eDNA's role in bacterial adhesion to abiotic surfaces. PLoS One 2014; 9:e105033. [PMID: 25122477 PMCID: PMC4133339 DOI: 10.1371/journal.pone.0105033] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 07/20/2014] [Indexed: 11/22/2022] Open
Abstract
Extracellular DNA (eDNA) is an important structural component of biofilms formed by many bacteria, but few reports have focused on its role in initial cell adhesion. The aim of this study was to investigate the role of eDNA in bacterial adhesion to abiotic surfaces, and determine to which extent eDNA-mediated adhesion depends on the physicochemical properties of the surface and surrounding liquid. We investigated eDNA alteration of cell surface hydrophobicity and zeta potential, and subsequently quantified the effect of eDNA on the adhesion of Staphylococcus xylosus to glass surfaces functionalised with different chemistries resulting in variable hydrophobicity and charge. Cell adhesion experiments were carried out at three different ionic strengths. Removal of eDNA from S. xylosus cells by DNase treatment did not alter the zeta potential, but rendered the cells more hydrophilic. DNase treatment impaired adhesion of cells to glass surfaces, but the adhesive properties of S. xylosus were regained within 30 minutes if DNase was not continuously present, implying a continuous release of eDNA in the culture. Removal of eDNA lowered the adhesion of S. xylosus to all surfaces chemistries tested, but not at all ionic strengths. No effect was seen on glass surfaces and carboxyl-functionalised surfaces at high ionic strength, and a reverse effect occurred on amine-functionalised surfaces at low ionic strength. However, eDNA promoted adhesion of cells to hydrophobic surfaces irrespective of the ionic strength. The adhesive properties of eDNA in mediating initial adhesion of S. xylosus is thus highly versatile, but also dependent on the physicochemical properties of the surface and ionic strength of the surrounding medium.
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Affiliation(s)
| | | | | | | | - Rikke L. Meyer
- Interdisciplinary Nanoscience Center (iNANO), Aarhus C, Denmark
- Department of Bioscience, Aarhus University, Aarhus C, Denmark
- * E-mail:
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15
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Regecová I, Pipová M, Jevinová P, Marušková K, Kmeť V, Popelka P. Species identification and antimicrobial resistance of coagulase-negative staphylococci isolated from the meat of sea fish. J Food Sci 2014; 79:M898-902. [PMID: 24689907 DOI: 10.1111/1750-3841.12429] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 02/04/2014] [Indexed: 11/30/2022]
Abstract
UNLABELLED Seventy-eight isolates of staphylococci obtained from the meat of Theragra chalcogramma, Scomber scombrus, and Clupea harengus were identified and tested in this study. 16S rDNA sequence specific for the genus Staphylococcus was detected in all isolates with the help of PCR method. All of 78 isolates were coagulase-negative, and DNAse activity was only confirmed in 4 of them. The following species of staphylococci were identified using MALDI-TOF mass spectrometry: S. warneri (52%), S. epidermidis (33%), S. haemolyticus (6.4%), S. pasteuri (3.8%), S. sciuri (1.2%), S. capitis (1.2%), and S. hominis (1.2%). Antimicrobial resistance to 7 antibiotics was determined in each isolate with the help of agar dilution method. In general, resistance against ampicillin was observed in majority of isolates (87%). On the contrary, the best sensitivity of CoNS was determined to gentamicin (96%). Only 1 S. warneri strain showed resistance to cefoxitin. Furthermore, 83% of staphylococcal isolates were simultaneously resistant to 2 or more antibiotics. PRACTICAL APPLICATION This study confirmed the need of monitoring antimicrobial resistance in coagulase-negative staphylococci not only in the meat of slaughter animals but also in retail marine fish. The results showed that MALDI-TOF mass spectrometry is useful, accurate, and rapid method for species identification of food pathogens including Staphylococcus spp.
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Affiliation(s)
- Ivana Regecová
- Dept. of Food Hygiene and Technology, Univ. of Veterinary Medicine and Pharmacy, Komenského 73, 041 81, Košice, Slovak Republic
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Antimicrobial activity of turmeric extract and its potential use in food industry. Journal of Food Science and Technology 2013; 52:2272-9. [PMID: 25829609 DOI: 10.1007/s13197-013-1195-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 09/24/2013] [Accepted: 10/03/2013] [Indexed: 10/26/2022]
Abstract
The present study investigates the antimicrobial and preservative potentials of turmeric extracts for food industry. Turmeric extracts prepared in n-hexane, water, chloroform and ethanol were applied to meals as preservatives and antibacterial agent. The samples were assessed microbiologically (total bacterial, total fungal and total coliform counts) and organoleptically (color, odor, taste) at day zero and after 15 days intervals. Meals autoclaved for shorter time (5 min) and treated with combination of 1 % or 2 % turmeric extract preserved for longer period. These results were comparable with samples autoclaved for longer period (15 min) with out turmeric extract. The antibacterial activities of different turmeric extracts were also tested against Escherichia coli, Staphylococcus aureus, Salmonella typhi and Candida albicans by disc diffusion method. Water extracted samples of turmeric stored at room temperature inhibited the growth of Escherichia coli and Salmonella typhi while aqueous extract autoclaved at 121 °C for 30 min reduced the growth of Escherichia coli and Staphylococcus aureus. Methanol extracted samples stored at room temperature or autoclaved at 121 °C was effective to control the growth of all microbes under study. Chloroform and n-hexane extracts (stored at room temperature) showed weak activity against all tested microbes.
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Li B, Zhang X, Guo F, Wu W, Zhang T. Characterization of tetracycline resistant bacterial community in saline activated sludge using batch stress incubation with high-throughput sequencing analysis. WATER RESEARCH 2013; 47:4207-4216. [PMID: 23764571 DOI: 10.1016/j.watres.2013.04.021] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 04/13/2013] [Accepted: 04/14/2013] [Indexed: 05/28/2023]
Abstract
An innovative and cost-effective method, i.e., batch stress incubation with tetracycline in combination with Cloning-Sanger sequencing and Illumina high-throughput sequencing was developed to identify tetracycline resistant bacteria (TRB) in activated sludge (AS) treating saline sewage. This method overcomes the drawbacks of culture-based approach (unrepresentative and biased results) and utilizes both the advantages of Cloning-Sanger sequencing and Illumina high-throughput sequencing, that is, long length read for correct taxonomic assignment at lower ranks and enough sequencing depth for accurate quantification of TRB communities with medium to low abundances, respectively. High precision (relative deviation ≤ 16.1%) was obtained for all taxon ranks with relative abundances over 0.01%. In the AS sample, TRB consisted of 13 genera with Haliea, Microbacterium and Paracoccus as dominate genera and 6 new TRB genera, i.e., Haliea, Rheinheimera, Alishewanella, Idiomarina, Pseudorhodobacter and Algoriphagus. The increase of tetG and tetA abundance might be associated with the significant increase of Pseudomonas (tetG and tetA host) in the AS after tetracycline stress incubation. tetS abundance also showed an obvious increase after 20 mg/L tetracycline treatment. This method provided a new tool to screen other antibiotic resistant bacteria, bacteria resistant to heavy metals or disinfectants in AS samples.
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Affiliation(s)
- Bing Li
- Environmental Biotechnology Lab, The University of Hong Kong, Hong Kong, China.
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Perreten V, Endimiani A, Thomann A, Wipf JR, Rossano A, Bodmer M, Raemy A, Sannes-Lowery KA, Ecker DJ, Sampath R, Bonomo RA. Evaluation of PCR electrospray-ionization mass spectrometry for rapid molecular diagnosis of bovine mastitis. J Dairy Sci 2013; 96:3611-20. [DOI: 10.3168/jds.2012-6124] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 02/22/2013] [Indexed: 01/16/2023]
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Abstract
Recently, a novel variant of mecA known as mecC (mecA(LGA251)) was identified in Staphylococcus aureus isolates from both humans and animals. In this study, we identified a Staphylococcus xylosus isolate that harbors a new allotype of the mecC gene, mecC1. Whole-genome sequencing revealed that mecC1 forms part of a class E mec complex (mecI-mecR1-mecC1-blaZ) located at the orfX locus as part of a likely staphylococcal cassette chromosome mec element (SCCmec) remnant, which also contains a number of other genes present on the type XI SCCmec.
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Xu B, Liu L, Liu L, Li X, Li X, Wang X. A multiplex PCR assay for the rapid and sensitive detection of methicillin-resistant Staphylococcus aureus and simultaneous discrimination of Staphylococcus aureus from coagulase-negative staphylococci. J Food Sci 2012; 77:M638-42. [PMID: 23106158 DOI: 10.1111/j.1750-3841.2012.02959.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a global health concern, which had been detected in food and food production animals. Conventional testing for detection of MRSA takes 3 to 5 d to yield complete information of the organism and its antibiotic sensitivity pattern. So, a rapid method is needed to diagnose and treat the MRSA infections. The present study focused on the development of a multiplex PCR assay for the rapid and sensitive detection of MRSA. The assay simultaneously detected 4 genes, namely, 16S rRNA of the Staphylococcus genus, femA of S. aureus, mecA that encodes methicillin resistance, and one internal control. It was rapid and yielded results within 4 h. The analytical sensitivity and specificity of the multiplex PCR assay was evaluated by comparing it with the conventional method. The analytical sensitivity of the multiplex PCR assay at the DNA level was 10 ng DNA. The analytical specificity was evaluated with 10 reference staphylococci strains and was 100%. The diagnostic evaluation of MRSA was carried out using 360 foodborne staphylococci isolates, and showed 99.1% of specificity, 96.4% of sensitivity, 97.5% of positive predictive value, and 97.3% of negative predictive value compared to the conventional method. The inclusion of an internal control in the multiplex PCR assay is important to exclude false-negative cases. This test can be used as an effective diagnostic and surveillance tool to investigate the spread and emergence of MRSA.
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Affiliation(s)
- Benjin Xu
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China.
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Moura TMD, Campos FS, d'Azevedo PA, Van Der Sand ST, Franco AC, Frazzon J, Frazzon APG. Prevalence of enterotoxin-encoding genes and antimicrobial resistance in coagulase-negative and coagulase-positive Staphylococcus isolates from black pudding. Rev Soc Bras Med Trop 2012; 45:579-85. [DOI: 10.1590/s0037-86822012000500008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 03/13/2012] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION: Staphylococcal species are pathogens that are responsible for outbreaks of foodborne diseases. The aim of this study was to investigate the prevalence of enterotoxin-genes and the antimicrobial resistance profile in staphylococcus coagulase-negative (CoNS) and coagulasepositive (CoPS) isolates from black pudding in southern Brazil. METHODS: Two hundred typical and atypical colonies from Baird-Parker agar were inoculated on mannitol salt agar. Eighty-two mannitol-positive staphylococci were submitted to conventional biochemical tests and antimicrobial susceptibility profiling. The presence of coagulase (coa) and enterotoxin (se) genes was investigated by polymerase chain reaction. RESULTS: The isolates were divided into 2 groups: 75.6% (62/82) were CoNS and 24.4% (20/82) were CoPS. The biochemical tests identified 9 species, of which Staphylococcus saprophyticus (37.8%) and Staphylococcus carnosus (15.9%) were the most prevalent. Antimicrobial susceptibility tests showed resistance phenotypes to antibiotics widely administered in humans, such as gentamicin, tetracycline, chloramphenicol, and erythromycin. The coa gene was detected in 19.5% (16/82) of the strains and 4 polymorphic DNA fragments were observed. Five CoNS isolates carrying the coa gene were submitted for 16S rRNA sequencing and 3 showed similarity with CoNS. Forty strains were positive for at least 1 enterotoxin-encoding gene, the genes most frequently detected were sea (28.6%) and seb (27.5%). CONCLUSIONS: The presence of antimicrobial resistant and enterotoxin-encoding genes in staphylococci isolates from black pudding indicated that this fermented food may represent a potential health risk, since staphylococci present in food could cause foodborne diseases or be a possible route for the transfer of antimicrobial resistance to humans.
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Affiliation(s)
- Tiane Martin de Moura
- Universidade Federal do Rio Grande do Sul; Universidade Federal do Rio Grande do Sul
| | | | | | | | - Ana Cláudia Franco
- Universidade Federal do Rio Grande do Sul; Universidade Federal do Rio Grande do Sul
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Abstract
The search for a specific rRNA methylase motif led to the identification of the new macrolide, lincosamide, and streptogramin B resistance gene erm(43) in Staphylococcus lentus. An inducible resistance phenotype was demonstrated by cloning and expressing erm(43) and its regulatory region in Staphylococcus aureus. The erm(43) gene was detected in two different DNA fragments, of 6,230 bp and 1,559 bp, that were each integrated at the same location in the chromosome in several S. lentus isolates of human, dog, and chicken origin.
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Seitter M, Nerz C, Rosenstein R, Götz F, Hertel C. DNA microarray based detection of genes involved in safety and technologically relevant properties of food associated coagulase-negative staphylococci. Int J Food Microbiol 2011; 145:449-58. [PMID: 21329998 DOI: 10.1016/j.ijfoodmicro.2011.01.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 12/21/2010] [Accepted: 01/16/2011] [Indexed: 10/18/2022]
Abstract
Aim of the work was to design a polynucleotide based DNA microarray as screening tool to detect genes in food associated coagulase-negative staphylococci (CNS). A focus was laid on genes with potential health concern and technological relevance. The microarray contained 220 probes for genes encoding antibiotic resistances, hemolysins, toxins, amino acid decarboxylases (e.g. biogenic amine formation), binding proteins to extracellular matrix (ECM), lipases, proteases, stress response factors, or nitrate dissimilation. Hybridization of genomic DNA isolated from 32 phenotypically characterized CNS permitted to detect numerous genes, corresponding with the phenotype. However, numerous hybridization signals were obtained for genes without any detectable phenotype. The antibiotic resistance genes blaZ, lnuA, and tetK involved in ß-lactam, lincomycin and tetracycline resistance, respectively, were rarely identified in CNS, however, all species contained some strains with such resistance genes. Decarboxylase genes involved in biogenic amine formation were detected regularly in Staphylococcus carnosus, S. condimenti, S. piscifermentans and S. equorum, but was rarely correlated with the phenotype. The same applied for the fibrinogen (clf) and fibronectin (fbp) binding protein genes, whose phenotype (binding assay) was only correlated in S. equorum and Staphylococcus succinus. Although some CNS showed hemolytic activity and enterotoxin production (Immunoblot) the corresponding genes could not be verified. Technological relevant genes such as proteases or lipases revealed good hybridization signals. In addition, genes involved in nitrate dissimilation (nre, nar, nir), catalase (kat), or superoxide dismutase (sod) were well detected. Interestingly, genes involved in dissimilatory nitrate reduction were more prevalent in strains of S. carnosus, S. condimenti and S. piscifermentans than of S. equorum, S. succinus and S. xylosus.
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Affiliation(s)
- Marion Seitter
- University of Hohenheim, Institute of Food Science and Biotechnology, Section Food Microbiology, Garbenstrasse 28, D-70599 Stuttgart, Germany
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Marino M, Frigo F, Bartolomeoli I, Maifreni M. Safety-related properties of staphylococci isolated from food and food environments. J Appl Microbiol 2010; 110:550-61. [PMID: 21143714 DOI: 10.1111/j.1365-2672.2010.04909.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIMS To test some safety-related properties within 321 staphylococci strains isolated from food and food environments. METHODS AND RESULTS The isolates were identified as Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Staphylococcus pasteuri, Staphylococcus sciuri, Staphylococcus warneri and Staphylococcus xylosus. Decarboxylase activity was quite common for the various Staphylococcus spp., and tyrosine was the most frequently decarboxylated amino acid. The frequency of antibiotic resistance was highest in Staph. pasteuri and Staph. xylosus. Several of the isolates were tolerant to QAC compounds, and in some cases, QAC tolerance was present in antibiotic-resistant strains. Most of the strains displayed moderate to high adhesion rates to stainless steel and Teflon(®). The strains that readily formed biofilms belonged to the species Staph. aureus, Staph. epidermidis and Staph. pasteuri. CONCLUSIONS An high incidence of some safety hazards was found within the staphylococcal strains of food origin tested in this study. In particular, amino acid decarboxylase activity and biofilm-forming ability were common within strains, and antibiotic resistance and tolerance to QAC-based compounds occurred frequently as well. These characteristics are an important safety concern for food industry. SIGNIFICANCE AND IMPACT OF THE STUDY This work gives a first picture of safety hazards within staphylococcal species isolated from food environments. The presence of disinfectant-resistant staphylococci is a concern because resistance can be genetically transferred between the various Staphylococcus species. This could lead an increase and spread of resistant enterotoxic staphylococci and/or pathogenic staphylococci.
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Affiliation(s)
- M Marino
- Department of Food Science, University of Udine, Udine, Italy.
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25
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Antibiotic resistance profile of Staphylococcus rostri, a new species isolated from healthy pigs. Vet Microbiol 2010; 145:165-71. [DOI: 10.1016/j.vetmic.2010.03.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 03/09/2010] [Accepted: 03/15/2010] [Indexed: 11/30/2022]
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26
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Coton E, Desmonts MH, Leroy S, Coton M, Jamet E, Christieans S, Donnio PY, Lebert I, Talon R. Biodiversity of Coagulase-Negative Staphylococci in French cheeses, dry fermented sausages, processing environments and clinical samples. Int J Food Microbiol 2010; 137:221-9. [DOI: 10.1016/j.ijfoodmicro.2009.11.023] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2009] [Revised: 11/19/2009] [Accepted: 11/24/2009] [Indexed: 11/29/2022]
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27
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HU YONGJIN, JIA JUNJING, QIAO JINLING, GE CHANGRONG, CAO ZHENGHUI. ANTIMICROBIAL ACTIVITY OF PU-ERH TEA EXTRACTSIN VITROAND ITS EFFECTS ON THE PRESERVATION OF COOLED MUTTON. J Food Saf 2010. [DOI: 10.1111/j.1745-4565.2009.00199.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Rodríguez-Alonso P, Fernández-Otero C, Centeno JA, Garabal JI. Antibiotic resistance in lactic acid bacteria and Micrococcaceae/Staphylococcaceae isolates from artisanal raw milk cheeses, and potential implications on cheese making. J Food Sci 2010; 74:M284-93. [PMID: 19723213 DOI: 10.1111/j.1750-3841.2009.01217.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Antibiotic susceptibility against 19 antimicrobial agents was evaluated in isolates of the genera Lactococcus (46 isolates), Leuconostoc (22), Lactobacillus (19), Staphylococcus (8), Enterococcus (7), and Microccoccus/Kocuria (5) obtained from the predominant microflora of nonrecent and recent types of artisanal raw cow's milk cheeses. Beta-lactams showed broad activity against all genera, although leuconostocs and lactobacilli were highly resistant to oxacillin (80% to 95.5%). Resistance to aminoglycosides was frequent for lactococci and enterococci (particularly for streptomycin), whereas lower rates of resistance were detected for lactobacilli and leuconostocs. Technologically interesting traits for the food industry were distributed among isolates that showed different degrees of resistance to common antibiotics. However, isolates showing resistance to less than 2 antibiotics were mainly those with properties of greatest technological interest (acidifying activity, proteolytic/lipolytic activities, or diacetyl production).
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Affiliation(s)
- P Rodríguez-Alonso
- Dairy Science and Technology Laboratory, Agricultural Research Center of Mabegondo (CIAM), Xunta de Galicia, 15080 A Coruña, Spain
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Faria C, Vaz-Moreira I, Serapicos E, Nunes OC, Manaia CM. Antibiotic resistance in coagulase negative staphylococci isolated from wastewater and drinking water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2009; 407:3876-3882. [PMID: 19324394 DOI: 10.1016/j.scitotenv.2009.02.034] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 02/12/2009] [Accepted: 02/26/2009] [Indexed: 05/27/2023]
Abstract
This study reports the antibiotic resistance patterns of coagulase negative staphylococci (CNS) isolated from a drinking water treatment plant (WTP), a drinking water distribution network, responsible for supplying water to the consumers (WDN), and a wastewater treatment plant (WWTP), responsible for receiving and treating domestic residual effluents. Genotyping and the 16S rRNA gene sequence analysis demonstrated a higher diversity of species both in the WTP (6 species/19 isolates) and WWTP (12 species/47 isolates) than in the WDN (6 species/172 isolates). Staphylococcus pasteuri and Staphylococcus epidermidis prevailed in the WTP and WDN and Staphylococcus saprophyticus in the WWTP. Staphylococci with reduced susceptibility (resistance or intermediary phenotype) to beta-lactams, tetracycline, clindamycin and erythromycin were observed in all types of water and belonged to the three major species groups. The highest resistance rate was found against erythromycin, presumably due to the presence of the efflux pump encoded by the determinant msrA, detected in the majority of the resistant isolates. This study demonstrates that antibiotic resistant CNS may colonize different types of water, namely drinking water fulfilling all the quality standards.
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Affiliation(s)
- Cátia Faria
- CBQF, Escola Superior de Biotecnologia, Universidade Católica Portuguesa, 4200-072 Porto, Portugal
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Removal of antibiotic resistance gene-carrying plasmids from Lactobacillus reuteri ATCC 55730 and characterization of the resulting daughter strain, L. reuteri DSM 17938. Appl Environ Microbiol 2008; 74:6032-40. [PMID: 18689509 DOI: 10.1128/aem.00991-08] [Citation(s) in RCA: 177] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The spread of antibiotic resistance in pathogens is primarily a consequence of the indiscriminate use of antibiotics, but there is concern that food-borne lactic acid bacteria may act as reservoirs of antibiotic resistance genes when distributed in large doses to the gastrointestinal tract. Lactobacillus reuteri ATCC 55730 is a commercially available probiotic strain which has been found to harbor potentially transferable resistance genes. The aims of this study were to define the location and nature of beta-lactam, tetracycline, and lincosamide resistance determinants and, if they were found to be acquired, attempt to remove them from the strain by methods that do not genetically modify the organism before subsequently testing whether the probiotic characteristics were retained. No known beta-lactam resistance genes was found, but penicillin-binding proteins from ATCC 55730, two additional resistant strains, and three sensitive strains of L. reuteri were sequenced and comparatively analyzed. The beta-lactam resistance in ATCC 55730 is probably caused by a number of alterations in the corresponding genes and can be regarded as not transferable. The strain was found to harbor two plasmids carrying tet(W) tetracycline and lnu(A) lincosamide resistance genes, respectively. A new daughter strain, L. reuteri DSM 17938, was derived from ATCC 55730 by removal of the two plasmids, and it was shown to have lost the resistances associated with them. Direct comparison of the parent and daughter strains for a series of in vitro properties and in a human clinical trial confirmed the retained probiotic properties of the daughter strain.
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Simeoni D, Rizzotti L, Cocconcelli P, Gazzola S, Dellaglio F, Torriani S. Antibiotic resistance genes and identification of staphylococci collected from the production chain of swine meat commodities. Food Microbiol 2008; 25:196-201. [DOI: 10.1016/j.fm.2007.09.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2006] [Revised: 03/20/2007] [Accepted: 09/06/2007] [Indexed: 11/24/2022]
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32
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Shan B, Cai YZ, Brooks JD, Corke H. The in vitro antibacterial activity of dietary spice and medicinal herb extracts. Int J Food Microbiol 2007; 117:112-9. [PMID: 17449125 DOI: 10.1016/j.ijfoodmicro.2007.03.003] [Citation(s) in RCA: 350] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Revised: 01/18/2007] [Accepted: 03/07/2007] [Indexed: 10/23/2022]
Abstract
The in vitro antibacterial activities of a total of 46 extracts from dietary spices and medicinal herbs were investigated by agar-well diffusion method against five foodborne bacteria (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, and Salmonella anatum). Their total phenolic contents were also evaluated. Many herb and spice extracts contained high levels of phenolics and exhibited antibacterial activity against foodborne pathogens. Gram-positive bacteria were generally more sensitive to the tested extracts than Gram-negative ones. S. aureus was the most sensitive, while E. coli was the most resistant. There were highly positive relationships (R(2)=0.73-0.93) between antibacterial activities and phenolic content of the tested extracts against each bacterium. This suggested that the antibacterial activity of the tested extracts was closely associated with their phenolic constituents.
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Affiliation(s)
- Bin Shan
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
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Simonová M, Strompfová V, Marciňáková M, Lauková A, Vesterlund S, Moratalla ML, Bover-Cid S, Vidal-Carou C. Characterization of Staphylococcus xylosus and Staphylococcus carnosus isolated from Slovak meat products. Meat Sci 2006; 73:559-64. [DOI: 10.1016/j.meatsci.2006.02.004] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2005] [Revised: 12/12/2005] [Accepted: 02/08/2006] [Indexed: 11/29/2022]
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Kastner S, Perreten V, Bleuler H, Hugenschmidt G, Lacroix C, Meile L. Antibiotic susceptibility patterns and resistance genes of starter cultures and probiotic bacteria used in food. Syst Appl Microbiol 2005; 29:145-55. [PMID: 16464696 DOI: 10.1016/j.syapm.2005.07.009] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Indexed: 11/24/2022]
Abstract
A survey of starter and probiotic cultures was carried out to determine the current antibiotic resistance situation in microbial food additives in Switzerland. Two hundred isolates from 90 different sources were typed by molecular and other methods to belong to the genera Lactobacillus (74 samples), Staphylococcus (33 samples), Bifidobacterium (6 samples), Pediococcus (5 samples), or were categorized as lactococci or streptococci (82 samples). They were screened for phenotypic resistances to 20 antibiotics by the disk diffusion method. Twenty-seven isolates exhibiting resistances that are not an intrinsic feature of the respective genera were further analyzed by microarray hybridization as a tool to trace back phenotypic resistances to specific genetic determinants. Their presence was finally verified by PCR amplification or Southern hybridization. These studies resulted in the detection of the tetracycline resistance gene tet(K) in 5 Staphylococcus isolates used as meat starter cultures, the tetracycline resistance gene tet(W) in the probiotic cultures Bifidobacterium lactis DSM 10140 and Lactobacillus reuteri SD 2112 (residing on a plasmid), and the lincosamide resistance gene lnu(A) (formerly linA) in L. reuteri SD 2112.
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Affiliation(s)
- Sabine Kastner
- Laboratory of Food Biotechnology, Institute of Food Science and Nutrition, Swiss Federal Institute of Technology (ETH), ETH-Zentrum, CH-8092 Zurich, Switzerland
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Perreten V, Vorlet-Fawer L, Slickers P, Ehricht R, Kuhnert P, Frey J. Microarray-based detection of 90 antibiotic resistance genes of gram-positive bacteria. J Clin Microbiol 2005; 43:2291-302. [PMID: 15872258 PMCID: PMC1153730 DOI: 10.1128/jcm.43.5.2291-2302.2005] [Citation(s) in RCA: 219] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A disposable microarray was developed for detection of up to 90 antibiotic resistance genes in gram-positive bacteria by hybridization. Each antibiotic resistance gene is represented by two specific oligonucleotides chosen from consensus sequences of gene families, except for nine genes for which only one specific oligonucleotide could be developed. A total of 137 oligonucleotides (26 to 33 nucleotides in length with similar physicochemical parameters) were spotted onto the microarray. The microarrays (ArrayTubes) were hybridized with 36 strains carrying specific antibiotic resistance genes that allowed testing of the sensitivity and specificity of 125 oligonucleotides. Among these were well-characterized multidrug-resistant strains of Enterococcus faecalis, Enterococcus faecium, and Lactococcus lactis and an avirulent strain of Bacillus anthracis harboring the broad-host-range resistance plasmid pRE25. Analysis of two multidrug-resistant field strains allowed the detection of 12 different antibiotic resistance genes in a Staphylococcus haemolyticus strain isolated from mastitis milk and 6 resistance genes in a Clostridium perfringens strain isolated from a calf. In both cases, the microarray genotyping corresponded to the phenotype of the strains. The ArrayTube platform presents the advantage of rapidly screening bacteria for the presence of antibiotic resistance genes known in gram-positive bacteria. This technology has a large potential for applications in basic research, food safety, and surveillance programs for antimicrobial resistance.
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Affiliation(s)
- Vincent Perreten
- Institute of Veterinary Bacteriology, University of Berne, Längass-Strasse 122, Postfach, CH-3001 Bern, Switzerland.
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Barbosa TM, Serra CR, La Ragione RM, Woodward MJ, Henriques AO. Screening for bacillus isolates in the broiler gastrointestinal tract. Appl Environ Microbiol 2005; 71:968-78. [PMID: 15691955 PMCID: PMC546680 DOI: 10.1128/aem.71.2.968-978.2005] [Citation(s) in RCA: 263] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2004] [Accepted: 09/28/2004] [Indexed: 11/20/2022] Open
Abstract
Spores from a number of different Bacillus species are currently being used as human and animal probiotics, although their mechanisms of action remain poorly understood. Here we describe the isolation of 237 presumptive gut-associated Bacillus spp. isolates that were obtained by heat and ethanol treatment of fecal material from organically reared broilers followed by aerobic plating. Thirty-one representative isolates were characterized according to their morphological, physiological, and biochemical properties as well as partial 16S rRNA gene sequences and screening for the presence of plasmid DNA. The Bacillus species identified included B. subtilis, B. pumilus, B. licheniformis, B. clausii, B. megaterium, B. firmus, and species of the B. cereus group, whereas a number of our isolates could not be classified. Intrinsic properties of potential importance for survival in the gut that could be advantageous for spore-forming probiotics were further investigated for seven isolates belonging to five different species. All isolates sporulated efficiently in the laboratory, and the resulting spores were tolerant to simulated gastrointestinal tract conditions. They also exhibited antimicrobial activity against a broad spectrum of bacteria, including food spoilage and pathogenic organisms such as Bacillus spp., Clostridium perfringens, Staphylococcus aureus, and Listeria monocytogenes. Importantly, the isolates were susceptible to most of the antibiotics tested, arguing that they would not act as donors for resistance determinants if introduced in the form of probiotic preparations. Together, our results suggest that some of the sporeformers isolated in this study have the potential to persist in or transiently associate with the complex gut ecosystem.
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Affiliation(s)
- Teresa M Barbosa
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, Apartado 127, 2781-901 Oeiras Codex, Portugal
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37
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Huys G, D'Haene K, Van Eldere J, von Holy A, Swings J. Molecular diversity and characterization of tetracycline-resistant Staphylococcus aureus isolates from a poultry processing plant. Appl Environ Microbiol 2005; 71:574-9. [PMID: 15640240 PMCID: PMC544260 DOI: 10.1128/aem.71.1.574-579.2005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2004] [Accepted: 08/23/2004] [Indexed: 11/20/2022] Open
Abstract
DNA fingerprinting and molecular characterization showed that the tetracycline-resistant Staphylococcus aureus population of a South African poultry processing plant comprised one or possibly several tet(K)-containing endemic clones that contaminated chicken and machinery surfaces at all sampled processing stages. The tet(K) gene was transferable by filter mating to S. aureus recipient 80CR5 and was located on a pT181-like plasmid.
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Affiliation(s)
- Geert Huys
- Laboratory of Microbiology, Ghent University, K.L. Ledeganckstr. 35, B-9000 Ghent, Belgium.
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38
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Schlegelová J, Nápravnı́ková E, Dendis M, Horváth R, Benedı́k J, Babák V, Klı́mová E, Navrátilová P, Šustáčková A. Beef carcass contamination in a slaughterhouse and prevalence of resistance to antimicrobial drugs in isolates of selected microbial species. Meat Sci 2004; 66:557-65. [DOI: 10.1016/s0309-1740(03)00159-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2002] [Revised: 06/18/2003] [Accepted: 06/27/2003] [Indexed: 11/24/2022]
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39
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Teuber M, Schwarz F, Perreten V. Molecular structure and evolution of the conjugative multiresistance plasmid pRE25 of Enterococcus faecalis isolated from a raw-fermented sausage. Int J Food Microbiol 2004; 88:325-9. [PMID: 14597005 DOI: 10.1016/s0168-1605(03)00195-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Plasmid pRE25 from Enterococcus faecalis transfers resistances against kanamycin, neomycin, streptomycin, clindamycin, lincomycin, azithromycin, clarithromycin, erythromycin, roxithromycin, tylosin, chloramphenicol, and nourseothricin sulfate by conjugation in vitro to E. faecalis JH2-2, Lactococcus lactis Bu2, and Listeria innocua L19. Its nucleotide sequence of 50237 base pairs represents the largest, fully sequenced conjugative multiresistance plasmid of enterococci (Plasmid 46 (2001) 170). The gene for chloramphenicol resistance (cat) was identified as an acetyltransferase identical to the one of plasmid pIP501 of Streptococcus agalactiae. Erythromycin resistance is due to a 23S ribosomal RNA methyl transferase, again as found in pIP501 (ermB). The aminoglycoside resistance genes are packed in tandem as in transposon Tn5405 of Staphylococcus aureus: an aminoglycoside 6-adenyltransferase, a streptothricin acetyl transferase, and an aminoglycoside phosphotransferase.). Identical resistance genes are known from pathogens like Streptococcus pyogenes, S. agalactiae, S. aureus, Campylobacter coli, Clostridium perfringens, and Clostridium difficile. pRE25 is composed of a 30.5-kbp segment almost identical to pIP501. Of the 15 genes involved in conjugative transfer, 10 codes for putative transmembrane proteins (e.g. trsB, traC, trsF, trsJ, and trsL). The enterococcal part is joined into the pIP501 part by insertion elements IS1216V of E. faecium Tn1545 (three copies), and homologs of IS1062 (E. faecalis) and IS1485 (E. faecium). pRE25 demonstrates that enterococci from fermented food do participate in the molecular communication between Gram-positive and Gram-negative bacteria of the human and animal microflora.
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Affiliation(s)
- Michael Teuber
- Laboratory of Food Microbiology, ETH Zurich, Zurich CH-8092, Switzerland.
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40
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Lopardo HA, Vidal P, Jeric P, Centron D, Paganini H, Facklam RR, Elliott J. Six-month multicenter study on invasive infections due to group B streptococci in Argentina. J Clin Microbiol 2003; 41:4688-94. [PMID: 14532204 PMCID: PMC254350 DOI: 10.1128/jcm.41.10.4688-4694.2003] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2003] [Revised: 06/09/2003] [Accepted: 07/30/2003] [Indexed: 11/20/2022] Open
Abstract
There is little information about invasive infections by group B streptococci (GBS) and their antimicrobial susceptibilities in Latin America. We performed a prospective multicenter study to determine the serotype distribution and the antimicrobial susceptibility of GBS in Argentina. We identified 58 cases, but only 44 had sufficient data to be evaluated. Eight early-, four late-, and one fatal late, late-onset neonatal infections due to GBS were found. A total of 31 patients were adults with bacteremia, skin and soft tissue infections, osteomyelitis, arthritis, meningitis, abdominal infections, and renal abscess. Serotype III was prevalent in late-onset neonatal disease, and several serotypes (Ia/c, III, Ia, and II) were involved in early-onset neonatal infections. Serotypes II, Ia/c, III, and IV were commonly found in adults, with serotype II prevalent in younger adults (18 to 69 years old) and serotype Ia/c prevalent in elderly adults (>70 years old). The mortality rate attributable to GBS infections was 10.8%. All GBS were susceptible to penicillin and ceftriaxone. Resistance to clindamycin (1.7%), erythromycin (5.2%), azithromycin (5.2%), minocycline (69%), and tetracycline (72.4%), to high levels of kanamycin and amikacin (1.7%), and to intermediately high levels of gentamicin (1.7%) was observed. The bifunctional enzyme AAC6'-APH2" was detected in the isolate resistant to aminoglycosides, and other genetic determinants were identified in other resistant isolates: tetM and tetO in tetracycline-resistant streptococci and mefA and ermTR for efflux-mediated and inducible macrolide-lincosamide-streptogramin B-resistant streptococci, respectively. For clinical purposes and rapid and easy detection of high-level aminoglycoside-resistant GBS, a screening method that used 1,000- micro g kanamycin disks is proposed.
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Affiliation(s)
- Horacio A Lopardo
- Servicio de Microbiología, Hospital de Pediatría, Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina.
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41
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Gardini F, Tofalo R, Suzzi G. A survey of antibiotic resistance in Micrococcaceae isolated from Italian dry fermented sausages. J Food Prot 2003; 66:937-45. [PMID: 12800992 DOI: 10.4315/0362-028x-66.6.937] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The transfer of bacteria that are resistant to antimicrobial agents or resistance genes from animals to humans via the food chain is increasingly a problem. Therefore, it is important to determine the species and the numbers of bacteria involved in this phenomenon. For this purpose, 148 strains of microstaphylococci were isolated from three types of Italian dry fermented sausages. Eight of 148 strains belonged to the genera Kocuria and Micrococcus. The remaining 140 strains belonged to 11 different species of the genus Staphylococcus. The species most frequently isolated was Staphylococcus xylosus, followed by Staphylococcus saprophyticus and Staphylococcus aureus. Antibiotic resistance levels differed among the species and depended on the strain origin. Microstaphylococci were generally susceptible to beta-lactams, but 12 strains were resistant to methicillin, 8 were resistant to oxacillin, and 9 were resistant to penicillin G. No resistance was observed for aminoglicosides and cephalosporines. Many strains were resistant to sulfonamide, colistin suphate, tetracyclin, and bacitracin. Two strains of S. aureus, four strains of S. xylosus, and one strain of Staphylococcus sciuri were able to grow in the presence of 8 microg of vancomycin per g, but all strains were susceptible to teicoplanin. Twenty-two microstaphylococci were resistant to at least five of the tested antibiotics. The multiresistant strain S. aureus 899 was unaffected by eight antibiotics, including vancomycin and methicillin, indicating that a more prudent use of antibiotics in animal husbandry and better hygienic conditions during production should be encouraged because they can play a major role in reducing the incidence of such multiresistant microorganisms and the possible spread of the genetic elements of their resistance.
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Affiliation(s)
- Fausto Gardini
- Dipartimento di Protezione e Valorizzazione Agroalimentare, Università degli Studi di Bologna, Via Fanin 46, 40127 Bologna, Italy.
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Friedman M, Henika PR, Mandrell RE. Bactericidal activities of plant essential oils and some of their isolated constituents against Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, and Salmonella enterica. J Food Prot 2002; 65:1545-60. [PMID: 12380738 DOI: 10.4315/0362-028x-65.10.1545] [Citation(s) in RCA: 609] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
An improved method of sample preparation was used in a microplate assay to evaluate the bactericidal activity levels of 96 essential oils and 23 oil compounds against Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica obtained from food and clinical sources. Bactericidal activity (BA50) was defined as the percentage of the sample in the assay mixture that resulted in a 50% decrease in CFU relative to a buffer control. Twenty-seven oils and 12 compounds were active against all four species of bacteria. The oils that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.009) were marigold, ginger root, jasmine, patchouli, gardenia, cedarwood, carrot seed, celery seed, mugwort, spikenard, and orange bitter oils; those that were most active against E. coli (with BA50 values ranging from 0.046 to 0.14) were oregano, thyme, cinnamon, palmarosa, bay leaf, clove bud, lemon grass, and allspice oils; those that were most active against L monocytogenes (with BA50 values ranging from 0.057 to 0.092) were gardenia, cedarwood, bay leaf, clove bud, oregano, cinnamon, allspice, thyme, and patchouli oils; and those that were most active against S. enterica (with BA50 values ranging from 0.045 to 0.14) were thyme, oregano, cinnamon, clove bud, allspice, bay leaf, palmarosa, and marjoram oils. The oil compounds that were most active against C. jejuni (with BA50 values ranging from 0.003 to 0.034) were cinnamaldehyde, estragole, carvacrol, benzaldehyde, citral, thymol, eugenol, perillaldehyde, carvone R, and geranyl acetate; those that were most active against E. coli (with BA50 values ranging from 0.057 to 0.28) were carvacrol, cinnamaldehyde, thymol, eugenol, salicylaldehyde, geraniol, isoeugenol, citral, perillaldehyde, and estragole; those that were most active against L monocytogenes (with BA50 values ranging from 0.019 to 0.43) were cinnamaldehyde, eugenol, thymol, carvacrol, citral, geraniol, perillaldehyde, carvone S, estragole, and salicylaldehyde; and those that were most active against S. enterica (with BA50 values ranging from 0.034 to 0.21) were thymol, cinnamaldehyde, carvacrol, eugenol, salicylaldehyde, geraniol, isoeugenol, terpineol, perillaldehyde, and estragole. The possible significance of these results with regard to food microbiology is discussed.
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Affiliation(s)
- Mendel Friedman
- Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California 94710, USA.
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43
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Huys G, D'Haene K, Swings J. Influence of the culture medium on antibiotic susceptibility testing of food-associated lactic acid bacteria with the agar overlay disc diffusion method. Lett Appl Microbiol 2002; 34:402-6. [PMID: 12028419 DOI: 10.1046/j.1472-765x.2002.01109.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To investigate the influence of the culture medium on antibiotic susceptibility testing of food-associated lactic acid bacteria (LAB) with the agar overlay disc diffusion (DD) method. METHOD The antibiotic resistance profile of 39 food-associated lactobacilli and enterococci was determined with the agar overlay DD method using a defined medium (i.e. Iso-sensitest agar; ISA) or an undefined medium (i.e. de Man, Rogosa, Sharpe or MRS agar). RESULTS The study revealed that ampicillin discs and, although to a lesser extent, also tetracycline discs consistently produced larger zones on MRS medium compared to ISA medium. For the antibiotics gentamicin, bacitracin and erythromycin, the radius of the inhibition zones produced on MRS medium was significantly smaller in relation to ISA. For categorizing LAB isolates into resistant, intermediate and susceptible groups, it was demonstrated that major errors can occur in determining bacitracin and gentamicin resistance if MRS medium instead of ISA medium is used. On the other hand, the performance of both media was found to be equivalent for testing tetracycline resistance. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY Despite the fact that MRS medium generally supports the growth of lactic acid bacteria much better than the nutrient-poor ISA medium, the present study clearly demonstrates that both media are not compatible in susceptibility testing against various classes of antibiotics. These results may stimulate future discussions on a generally recommended DD method for susceptibility testing of food LAB strains.
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Affiliation(s)
- G Huys
- Laboratory of Microbiology, Ghent University, Ghent, Belgium.
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44
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Schlegelová J, Babák V, Klímová E, Lukásová J, Navrátilová P, Sustácková A, Sedivá I, Rysánek D. Prevalence of and resistance to anti-microbial drugs in selected microbial species isolated from bulk milk samples. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2002; 49:216-25. [PMID: 12121041 DOI: 10.1046/j.1439-0450.2002.00520.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The prevalence of strains of Staphylococcus aureus, coagulase-negative (CN) staphylococci, Listeria monocytogenes, Escherichia coli, Enterococcus faecalis, E. faecium and Bacillus cereus, was investigated in 111 bulk milk samples. Staphylococcus aureus was isolated from 38 samples, CN staphylococci from 63 samples, E. coli from 49 samples, E. faecalis or E. faecium from 107 samples, and L. monocytogenes from two samples. Bacillus cereus was not found in any of the samples and three samples were free of any of the selected species. Sensitivity to the anti-microbial drugs amikacin, ampicillin, ampicillin + sulbactam, cephalothin (CLT), cephotaxime, clindamycin, chloramphenicol (CMP), co-trimoxazole, erythromycin (ERY), gentamicin, neomycin, norfloxacin, oxacillin, penicillin, streptomycin (STR), tetracycline (TTC) and vancomycin was tested using the standard dilution technique. Minimum inhibitory concentration (MIC) characteristics (MIC50, MIC90, MIC range) were determined for each microbial species. Resistance against one or more anti-microbial drugs was found in 93% of S. aureus, 40% of CN staphylococci, 73% of E. coli, 88% of E.faecalis, 55% of E.faecium, and one L. monocytogenes strain. Most of the strains, particularly enterococci, were resistant to STR, TTC, and ERY (MIC50 4 microg/ml). A high percentage of staphylococci were resistant to beta-lactam antibiotics. High resistance to CLT was found in 11 strains of E. coli (MIC 256 microg/ml) and strains resistant to CMP (MIC90 16 microg/ml) were detected. The highest numbers of resistance phenotypes were found in E. coil (16) and CN staphylococci (12). Eighteen identical resistance phenotypes were demonstrated in indicator bacteria (E. coli, E. faecalis, E. faecium) and pathogens (S. aureus, CN staphylococci) isolated from the same bulk milk sample. The obtained resistance data were matched against the herd owners' information on therapeutic use of the drugs. This confrontation could not explain the findings of strains resistant to ERY or CMP. Our findings are evidence of selection of resistant strains among not only pathogenic agents, but also among indicator bacteria which can become significant carriers of transmissible resistance genes.
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Affiliation(s)
- J Schlegelová
- Veterinary Research Institute, Brno, Czech Republic.
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45
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Schwarz FV, Perreten V, Teuber M. Sequence of the 50-kb conjugative multiresistance plasmid pRE25 from Enterococcus faecalis RE25. Plasmid 2001; 46:170-87. [PMID: 11735367 DOI: 10.1006/plas.2001.1544] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The complete 50,237-bp DNA sequence of the conjugative and mobilizing multiresistance plasmid pRE25 from Enterococcus faecalis RE25 was determined. The plasmid had 58 putative open reading frames, 5 of which encode resistance to 12 antimicrobials. Chloramphenicol acetyltransferase and the 23S RNA methylase are identical to gene products of the broad-host-range plasmid pIP501 from Streptococcus agalactiae. In addition, a 30.5-kb segment is almost identical to pIP501. Genes encoding an aminoglycoside 6-adenylyltransferase, a streptothricin acetyltransferase, and an aminoglycoside phosphotransferase are arranged in tandem on a 7.4-kb fragment as previously reported in Tn5405 from Staphylococcus aureus and in pJH1 from E. faecalis. One interrupted and five complete IS elements as well as three replication genes were also identified. pRE25 was transferred by conjugation to E. faecalis, Listeria innocua, and Lactococcus lactis by means of a transfer region that appears similar to that of pIP501. It is concluded that pRE25 may contribute to the further spread of antibiotic-resistant microorganisms via food into the human community.
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Affiliation(s)
- F V Schwarz
- Laboratory for Food Microbiology, Swiss Federal Institute of Technology of Zurich, Zurich, CH-8092, Switzerland
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46
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Abstract
Live recombinant bacteria represent an attractive means to induce both mucosal and systemic immune responses against heterologous antigens. Several models have now been developed and shown to be highly efficient following intranasal immunization. In this review, we describe the two main classes of live recombinant bacteria: generally recognized as safe bacteria and attenuated strains derived from pathogenic bacteria. Among the latter, we have differentiated the bacteria, which do not usually colonize the respiratory tract from those that are especially adapted to respiratory tissues. The strategies of expression of the heterologous antigens, the invasiveness and the immunogenicity of the recombinant bacteria are discussed.
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Affiliation(s)
- N Mielcarek
- INSERM U447, IBL, Institut Pasteur of Lille, 1 Rue du Pr. Calmette, 59019, Lille, France
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47
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Frei A, Goldenberger D, Teuber M. Antimicrobial susceptibility of intestinal bacteria from Swiss poultry flocks before the ban of antimicrobial growth promoters. Syst Appl Microbiol 2001; 24:116-21. [PMID: 11403390 DOI: 10.1078/0723-2020-00004] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
From the crop and the caecum of Swiss broilers slaughtered between November 1997 and January 1998, Escherichia coli, enterococci, staphylococci, lactobacilli and Campylobacter species were isolated. After identification to the genus or species level, their minimal inhibitory concentrations (MIC's) for several clinically used antimicrobial agents were determined with the E-Test stripes and compared to those from studies in other European countries. All strains of Enterococcus faecalis (n = 38), E. faecium (27), staphylococci (n = 39) and lactobacilli (n = 14) showed a hundred percent resistance against bacitracin which was included in the feed of the mother animals, but not in the feed of the investigated animals. E.coli strains (n = 60) showed higher resistance incidences than in comparable studies from Finland and Denmark, but lower than those in studies from Italy and Germany. In staphylococci, low resistance rates were observed. A high susceptibility of the 13 Campylobacter jejuni strains was found against therapeutically used antimicrobials. These data can be used as a baseline to determine antibiotic resistance rates after implementation of the growth promotor ban in 1999 in Switzerland.
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Affiliation(s)
- A Frei
- Department of Food Science, Swiss Federal Institute of Technology, Zürich
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Nawaz MS, Khan SA, Khan AA, Khambaty FM, Cerniglia CE. Comparative molecular analysis of erythromycin-resistance determinants in staphylococcal isolates of poultry and human origin. Mol Cell Probes 2000; 14:311-9. [PMID: 11040095 DOI: 10.1006/mcpr.2000.0320] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The ermA, ermB, ermC and msrA/msrB genes were detected in multidrug-resistant Staphylococcus spp. strains by PCR. Among 25 human clinical staphylococcal isolates the ermA, ermB, ermC and the msrA/msrB genes were detected in 88, 72, 4 and 100% of the strains, respectively. Among 24 poultry isolates the ermA, ermB, ermC and the msrA/msrB genes were detected in 100, 16.6, 50 and 12.5% of the strains, respectively. The ermA gene was found exclusively on the chromosome, whereas the ermC gene was found on 2.4-4.2 kb plasmids. Restriction fragment length polymorphism (RFLP) analysis of the ermA gene with Eco RI revealed five patterns (25.0, 21.0, 10.5, 6.2 and 4. 8 kb) for the clinical strains and two (8.0 and 6.2 kb) for the poultry strains. The 6.2 kb RFLP pattern, in both the poultry and human clinical isolates, indicates a common lineage for the ermA gene.
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Affiliation(s)
- M S Nawaz
- Division of Microbiology, National Center for Toxicological Research/FDA, 3900 NCTR Road, Jefferson, AR 72079, USA.
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49
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Patel A, Lloyd D, Lamport A. Antimicrobial resistance of feline staphylococci in south-eastern England. Vet Dermatol 1999; 10:257-261. [DOI: 10.1046/j.1365-3164.1999.00178.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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