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The Changing Face of the Family Enterobacteriaceae (Order: " Enterobacterales"): New Members, Taxonomic Issues, Geographic Expansion, and New Diseases and Disease Syndromes. Clin Microbiol Rev 2021; 34:34/2/e00174-20. [PMID: 33627443 DOI: 10.1128/cmr.00174-20] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The family Enterobacteriaceae has undergone significant morphogenetic changes in its more than 85-year history, particularly during the past 2 decades (2000 to 2020). The development and introduction of new and novel molecular methods coupled with innovative laboratory techniques have led to many advances. We now know that the global range of enterobacteria is much more expansive than previously recognized, as they play important roles in the environment in vegetative processes and through widespread environmental distribution through insect vectors. In humans, many new species have been described, some associated with specific disease processes. Some established species are now observed in new infectious disease settings and syndromes. The results of molecular taxonomic and phylogenetics studies suggest that the current family Enterobacteriaceae should possibly be divided into seven or more separate families. The logarithmic explosion in the number of enterobacterial species described brings into question the relevancy, need, and mechanisms to potentially identify these taxa. This review covers the progression, transformation, and morphogenesis of the family from the seminal Centers for Disease Control and Prevention publication (J. J. Farmer III, B. R. Davis, F. W. Hickman-Brenner, A. McWhorter, et al., J Clin Microbiol 21:46-76, 1985, https://doi.org/10.1128/JCM.21.1.46-76.1985) to the present.
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Rivera-Izquierdo M, Láinez-Ramos-Bossini AJ, Rivera-Izquierdo C, López-Gómez J, Fernández-Martínez NF, Redruello-Guerrero P, Martín-delosReyes LM, Martínez-Ruiz V, Moreno-Roldán E, Jiménez-Mejías E. OXA-48 Carbapenemase-Producing Enterobacterales in Spanish Hospitals: An Updated Comprehensive Review on a Rising Antimicrobial Resistance. Antibiotics (Basel) 2021; 10:antibiotics10010089. [PMID: 33477731 PMCID: PMC7832331 DOI: 10.3390/antibiotics10010089] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/07/2021] [Accepted: 01/16/2021] [Indexed: 12/14/2022] Open
Abstract
Carbapenemase-producing Enterobacterales (CPE) are significant contributors to the global public health threat of antimicrobial resistance. OXA-48-like enzymes and their variants are unique carbapenemases with low or null hydrolytic activity toward carbapenems but no intrinsic activity against expanded-spectrum cephalosporins. CPEs have been classified by the WHO as high-priority pathogens given their association with morbidity and mortality and the scarce number of effective antibiotic treatments. In Spain, the frequency of OXA-48 CPE outbreaks is higher than in other European countries, representing the major resistance mechanism of CPEs. Horizontal transfer of plasmids and poor effective antibiotic treatment are additional threats to the correct prevention and control of these hospital outbreaks. One of the most important risk factors is antibiotic pressure, specifically carbapenem overuse. We explored the use of these antibiotics in Spain and analyzed the frequency, characteristics and prevention of CPE outbreaks. Future antibiotic stewardship programs along with specific preventive measures in hospitalized patients must be reinforced and updated in Spain.
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Olivera C, Le VVH, Davenport C, Rakonjac J. In vitro synergy of 5-nitrofurans, vancomycin and sodium deoxycholate against Gram-negative pathogens. J Med Microbiol 2021; 70. [PMID: 33448923 PMCID: PMC8346734 DOI: 10.1099/jmm.0.001304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Introduction There is an urgent need for effective therapies against bacterial infections, especially those caused by antibiotic-resistant Gram-negative pathogens. Hypothesis Synergistic combinations of existing antimicrobials show promise due to their enhanced efficacies and reduced dosages which can mitigate adverse effects, and therefore can be used as potential antibacterial therapy. Aim In this study, we sought to characterize the in vitro interaction of 5-nitrofurans, vancomycin and sodium deoxycholate (NVD) against pathogenic bacteria. Methodology The synergy of the NVD combination was investigated in terms of growth inhibition and bacterial killing using checkerboard and time-kill assays, respectively. Results Using a three-dimensional checkerboard assay, we showed that 5-nitrofurans, sodium deoxycholate and vancomycin interact synergistically in the growth inhibition of 15 out of 20 Gram-negative strains tested, including clinically significant pathogens such as carbapenemase-producing Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii, and interact indifferently against the Gram-positive strains tested. The time-kill assay further confirmed that the triple combination was bactericidal in a synergistic manner. Conclusion This study demonstrates the synergistic effect of 5-nitrofurans, sodium deoxycholate and vancomycin against Gram-negative pathogens and highlights the potential of the combination as a treatment for Gram-negative and Gram-positive infections.
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Zhestkov AV, Zolotov MO, Lyamin AV, Borisova OV, Chernova OE, Limareva LV, Ismatullin DD. [Experience with 13-valent conjugated pneumococcal vaccine in HIV-infected patients]. TERAPEVT ARKH 2020; 92:38-44. [PMID: 33720602 DOI: 10.26442/00403660.2020.11.000861] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 12/25/2020] [Indexed: 11/22/2022]
Abstract
AIM Evaluate the effect of PCV13 vaccination on the composition of the microflora of the upper respiratory tract and the immune system in HIV-infected patients. MATERIALS AND METHODS 100 patients with HIV-infection were included in the study. The patients underwent immunological examination and the collection of biomaterial from the posterior pharyngeal wall for microbiological examination. After obtaining the results of the examinations, PCV13 was intramuscularly administered. 7 days after the introduction of the vaccine, an assessment of adverse events was carried out, after 3 months, microbiological and immunological examinations were repeated. RESULTS Immediately after the administration of PCV13, 5% of patients felt pain during the administration. Local reactions were reported in 6 patients. One participant showed a rise in temperature to 38.3C over 2 days. Before vaccination, 16 strains of S. pneumoniae were seeded in patients. 3 months after the administration of PCV13, pneumococcus was isolated in 8 patients. 3 months after immunization, the median level of populations and subpopulations of lymphocytes became higher than the pre-vaccination. DISCUSSION Our results show high risk of pneumococcal infections in HIV-positive patients. A tendency towards a decrease in the level of S. pneumoniae carriage was revealed 3 months after the administration of PCV13. The high level of enterobacteria carriage in HIV-positive patients is noteworthy. There is a pronounced positive effect from the use of PCV13 in HIV-positive patients on cellular factors of the immune system. CONCLUSION The use of PCV13 is a safe and effective method for the prevention of S. pneumoniae infections.
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Telhig S, Ben Said L, Zirah S, Fliss I, Rebuffat S. Bacteriocins to Thwart Bacterial Resistance in Gram Negative Bacteria. Front Microbiol 2020; 11:586433. [PMID: 33240239 PMCID: PMC7680869 DOI: 10.3389/fmicb.2020.586433] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/16/2020] [Indexed: 12/16/2022] Open
Abstract
An overuse of antibiotics both in human and animal health and as growth promoters in farming practices has increased the prevalence of antibiotic resistance in bacteria. Antibiotic resistant and multi-resistant bacteria are now considered a major and increasing threat by national health agencies, making the need for novel strategies to fight bugs and super bugs a first priority. In particular, Gram-negative bacteria are responsible for a high proportion of nosocomial infections attributable for a large part to Enterobacteriaceae, such as pathogenic Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. To cope with their highly competitive environments, bacteria have evolved various adaptive strategies, among which the production of narrow spectrum antimicrobial peptides called bacteriocins and specifically microcins in Gram-negative bacteria. They are produced as precursor peptides that further undergo proteolytic cleavage and in many cases more or less complex posttranslational modifications, which contribute to improve their stability and efficiency. Many have a high stability in the gastrointestinal tract where they can target a single pathogen whilst only slightly perturbing the gut microbiota. Several microcins and antibiotics can bind to similar bacterial receptors and use similar pathways to cross the double-membrane of Gram-negative bacteria and reach their intracellular targets, which they also can share. Consequently, bacteria may use common mechanisms of resistance against microcins and antibiotics. This review describes both unmodified and modified microcins [lasso peptides, siderophore peptides, nucleotide peptides, linear azole(in)e-containing peptides], highlighting their potential as weapons to thwart bacterial resistance in Gram-negative pathogens and discusses the possibility of cross-resistance and co-resistance occurrence between antibiotics and microcins in Gram-negative bacteria.
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de Menezes MP, Facin AC, Cardozo MV, Costa MT, Moraes PC. Evaluation of the Resistance Profile of Bacteria Obtained From Infected Sites of Dogs in a Veterinary Teaching Hospital in Brazil: A Retrospective Study. Top Companion Anim Med 2020; 42:100489. [PMID: 33144265 DOI: 10.1016/j.tcam.2020.100489] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 10/06/2020] [Accepted: 10/12/2020] [Indexed: 02/06/2023]
Abstract
The aim of this study was to evaluate the prevalence and antimicrobial resistance profile of bacterial species isolated from infected sites of canines. All samples were collected from canine patients who received clinical or surgical care at the veterinary teaching hospital between March 2016 and November 2017. The samples were analyzed in a private pathology laboratory. A descriptive analysis of 295 antimicrobial susceptibility test reports was performed. Staphylococcus spp. (104/295 [35.25%]), Escherichia coli (100/295 [33.90%]), Proteus spp. (44/295 [14.92%]), Pseudomonas spp. (25/295 [8.47%]), and Klebsiella spp. (20/295 [6.78%]) were more frequently isolated, and a high incidence of multidrug resistance was observed (69,83% [206/295]). Methicillin-resistant Staphylococcus spp. accounted for 33% (33/100) of the Staphylococcus strains. Enterobacteriaceae cefotaxime resistance constituted 22.82 ± 4.49% and Enterobacteriaceae imipenem resistance constituted 5% (1/20) for Klebsiella spp., 5% (5/100) for E coli, and 6.82% (3/44) for Proteus spp. Pseudomonas spp. strains accounted for 8% (2/25) of imipenem resistance and 45.45% (10/22) of polymyxin B resistance. Our findings revealed a high rate of multidrug-resistant bacteria involvement in the infectious process of dogs. From the perspective of the One Health scenario, our results showed alarming data, given the high risk of resistant-strain dissemination between animals, owners, and healthcare professionals. There is an urgent need for strategies to control and prevent the evolution of new multidrug-resistant bacteria in veterinary hospitals. It is also crucial to understand and emphasize the role of veterinary professionals in this public health battle.
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Dupré M, Duchateau M, Malosse C, Borges-Lima D, Calvaresi V, Podglajen I, Clermont D, Rey M, Chamot-Rooke J. Optimization of a Top-Down Proteomics Platform for Closely Related Pathogenic Bacterial Discrimination. J Proteome Res 2020; 20:202-211. [PMID: 32929970 DOI: 10.1021/acs.jproteome.0c00351] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The current technique used for microbial identification in hospitals is matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). However, it suffers from important limitations, in particular, for closely related species or when the database used for the identification lacks the appropriate reference. In this work, we set up a liquid chromatography (LC)-MS/MS top-down proteomics platform, which aims at discriminating closely related pathogenic bacteria through the identification of specific proteoforms. Using Escherichia coli as a model, all steps of the workflow were optimized: protein extraction, on-line LC separation, MS method, and data analysis. Using optimized parameters, about 220 proteins, corresponding to more than 500 proteoforms, could be identified in a single run. We then used this platform for the discrimination of enterobacterial pathogens undistinguishable by MALDI-TOF, although leading to very different clinical outcomes. For each pathogen, we identified specific proteoforms that could potentially be used as biomarkers. We also improved the characterization of poorly described bacterial strains. Our results highlight the advantage of addressing proteoforms rather than peptides for accurate bacterial characterization and qualify top-down proteomics as a promising tool in clinical microbiology. Data are available via ProteomeXchange with the identifier PXD019247.
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Charmpi C, Van Reckem E, Sameli N, Van der Veken D, De Vuyst L, Leroy F. The Use of Less Conventional Meats or Meat with High pH Can Lead to the Growth of Undesirable Microorganisms during Natural Meat Fermentation. Foods 2020; 9:foods9101386. [PMID: 33019548 PMCID: PMC7601081 DOI: 10.3390/foods9101386] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 09/25/2020] [Accepted: 09/29/2020] [Indexed: 12/16/2022] Open
Abstract
The bacterial communities that are established during natural meat fermentation depend on the processing conditions and the type of meat substrate used. Six pork samples of variable quality (reflected in pH values) and six less conventional meats (beef, horse, hare, wild deer, wild duck, and wild boar) were naturally fermented under controlled conditions in model systems. The development of lactic acid bacteria (LAB), coagulase-negative staphylococci (CNS), and enterobacteria was followed using culture-dependent techniques and (GTG)5-PCR fingerprinting of genomic DNA from the isolates obtained. Taken together, Latilactobacillus sakei was the most abundant LAB species, although Latilactobacillus curvatus was more manifest in high-pH pork. Within staphylococci, common species were encountered (i.e., Staphylococcus equorum, Staphylococcus saprophyticus, and Staphylococcus xylosus), although some atypical ones (i.e., Staphylococcus succinus) were also recovered. Within enterobacteria, Serratia spp. prevailed in more acidic pork batches and in beef, whereas Hafnia spp. prevailed in game meat fermentations. Enterobacterial counts were particularly high in fermentations with low acidity, namely for some pork batches, hare, wild duck, and wild boar. These findings should be considered when naturally fermented meat products are manufactured, as the use of game meat or meat with high pH can give rise to safety concerns.
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O'Meara FM, Gardiner GE, Clarke D, Cummins W, O'Doherty JV, Lawlor PG. Microbiological assessment of liquid feed for finisher pigs on commercial pig units. J Appl Microbiol 2020; 130:356-369. [PMID: 32681565 DOI: 10.1111/jam.14785] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/09/2020] [Accepted: 07/09/2020] [Indexed: 11/26/2022]
Abstract
AIMS To investigate the microbiological and nutritional quality of liquid finisher pig feed on commercial production units and the factors influencing this. METHODS AND RESULTS Microbiological and physio-chemical analyses were performed on liquid feed sampled from the mixing tank and troughs of the finisher section of eight commercial pig units. Lactic acid bacteria, yeast and Escherichia coli counts, as well as lactic acid, ethanol and acetate concentrations were higher in residual feed sampled from the troughs compared with mixing tank samples (P < 0·001). Feed pH, as well as lysine, methionine and threonine concentrations and gross energy were all lower in the residual trough samples (P < 0·001). Liquid co-products reduced E. coli counts in the residual trough samples (P < 0·05), pH in the mixing tank (P < 0·01) and fresh trough samples (P < 0·05) and mould counts at all three sampling locations (P < 0·01) but sanitation practices had no impact. CONCLUSIONS Even when considered unfermented, a considerable degree of spontaneous fermentation occurs in liquid feed, with resultant negative effects on nutritional quality. SIGNIFICANCE AND IMPACT OF THE STUDY This is one of the first studies showing that uncontrolled fermentation of fresh liquid pig feed is commonplace on commercial units, highlighting the need for implementation of suitable control strategies.
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Djim-Adjim-Ngana K, Oumar LA, Mbiakop BW, Njifon HLM, Crucitti T, Nchiwan EN, Yanou NN, Deweerdt L. Prevalence of extended-spectrum beta-lactamase-producing enterobacterial urinary infections and associated risk factors in small children of Garoua, Northern Cameroon. Pan Afr Med J 2020; 36:157. [PMID: 32874421 PMCID: PMC7436643 DOI: 10.11604/pamj.2020.36.157.21347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/09/2020] [Indexed: 12/03/2022] Open
Abstract
Introduction the emergence of extended-spectrum beta-lactamase-producing Entero bacteriaceae (E-ESBLs) is currently a major public health problem in the world and, in particular, in developing countries. In Cameroon, data on E-ESBLs are rare, especially in Garoua and in the northern region of the country. The objective of this study is to document the epidemiology of E-ESBL infections in small children and to explore their associations with possible risk factors. Methods this was a cross-sectional, descriptive study conducted from June 14 to September 30, 2018, including small children with suspected urinary tract infections (UTI) attending the outpatient pediatric departments of two health facilities in the city of Garoua. Urine samples were analyzed at the Bacteriology Laboratory of the Pasteur Center of Cameroon, Annex Garoua. Bacterial culture was carried out on Bio-Rad UriSelect® chromogenic agar and the identification was confirmed by bioMérieux API 20E. The antibiotic susceptibility was determined using the bioMérieux ATB UR gallery and the ESBL phenotype was detected by the double disk synergy method according to the CA-SFM 2013 recommendations. The data was analyzed with the R Statistical Software version 2.15.2. Results a total of 57 urine samples were collected from children aged from one month to two years, 37 boys and 20 girls. Bacteria were detected by culture in 20 samples: Escherichia coliwas the most frequently (75 %) isolated species followed by Klebsiella pneumoniae(25%). More than half of the infected samples (55%) contained E-ESBL. The presence of an ESBL was significantly associated with previous antibiotic intake up to 3 months prior current UTI (p=0.01664). The E-ESBL strains showed co-resistance to different antibiotics. Conclusion this study reveals the important dissemination of E-ESBLs among small children in the community and a high rate of co-resistance to the different antibiotic families commonly used.
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MLADENOVIĆ KG, GRUJOVIĆ MŽ, NIKODIJEVIĆ DD, ČOMIĆ LR. The hydrophobicity of enterobacteria and their co-aggregation with Enterococcus faecalis isolated from Serbian cheese. BIOSCIENCE OF MICROBIOTA, FOOD AND HEALTH 2020; 39:227-233. [PMID: 33117621 PMCID: PMC7573113 DOI: 10.12938/bmfh.2020-004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 06/11/2020] [Indexed: 11/25/2022]
Abstract
In this paper, we investigated the hydrophobicity, ability to adhere to solvents and the pig epithelium and co-aggregation of members of family Enterobacteriaceae and Enterococcus faecalis KGPMF 49. The bacteria used in this study were isolated from traditionally made autochthonous cheese from Southeastern Serbia (Sokobanja). The percentage of adhered bacteria was different in three solvents (chloroform, ethyl acetate and xylene). The highest percentage was detected in the presence of chloroform, and the lowest percentage was detected in the presence of xylene (chloroform < ethyl acetate < xylene). A different degree of co-aggregation of enterobacteria with E. faecalis KGPMF 49 was observed. Klebsiella ornithinolytica KGPMF 8 demonstrated the highest percentage of co-aggregation with E. faecalis KGPMF49 (32.29%). Klebsiella pneumoniae KGPMF 13, K. ornithinolytica KGPMF 9 and Serratia marcescens biogp 1 KGPMF 19 were found to have the ability to adhere to the pig epithelium, whereas Escherichia coli KGPMF 22 showed no such ability. The ability to co-aggregate with other species and the ability to adhere to the pig epithelium are very important characteristics of the isolated bacteria.
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Abstract
Infections of genotoxic Escherichia coli spread concomitantly with urbanized progression. These bacteria may prompt cell senescence and affect DNA stability, inducing cancer via the production of colibactin, a genotoxin shown capable of affecting host DNA in eukaryotic cells. In this study, we show that the action of colibactin may also be directed against other bacteria of the gut microbiota in which genotoxic E. coli bacteria have been introduced. Indeed, the presence of genotoxic E. coli induced a change in both the structure and function of the gut microbiota. Our data indicate that genotoxic E. coli may use colibactin to compete for gut niche utilization. The genotoxin colibactin produced by resident bacteria of the gut microbiota may have tumorigenic effect by inducing DNA double-strand breaks in host cells. Yet, the effect of colibactin on gut microbiota composition and functions remains unknown. To address this point, we designed an experiment in which pregnant mice were colonized with the following: (i) a commensal Escherichia coli strain, (ii) a commensal E. coli strain plus a genotoxic E. coli strain, (iii) a commensal E. coli strain plus a nongenotoxic E. coli mutant strain unable to produce mature colibactin. Then, we analyzed the gut microbiota in pups at day 15 and day 35 after birth. At day 15, mice that were colonized at birth with the genotoxic strain showed lower levels of Proteobacteria and taxa belonging to the Proteobacteria, a modest effect on overall microbial diversity, and no effect on gut microbiome. At day 35, mice that received the genotoxic strain showed lower Firmicutes and taxa belonging to the Firmicutes, together with a strong effect on overall microbial diversity and higher microbial functions related to DNA repair. Moreover, the genotoxic strain strongly affected gut microbial diversity evolution of pups receiving the genotoxic strain between day 15 and day 35. Our data show that colibactin, beyond targeting the host, may also exert its genotoxic effect on the gut microbiota. IMPORTANCE Infections of genotoxic Escherichia coli spread concomitantly with urbanized progression. These bacteria may prompt cell senescence and affect DNA stability, inducing cancer via the production of colibactin, a genotoxin shown capable of affecting host DNA in eukaryotic cells. In this study, we show that the action of colibactin may also be directed against other bacteria of the gut microbiota in which genotoxic E. coli bacteria have been introduced. Indeed, the presence of genotoxic E. coli induced a change in both the structure and function of the gut microbiota. Our data indicate that genotoxic E. coli may use colibactin to compete for gut niche utilization.
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Tápparo DC, Viancelli A, Amaral ACD, Fongaro G, Steinmetz RLR, Magri ME, Barardi CRM, Kunz A. Sanitary effectiveness and biogas yield by anaerobic co-digestion of swine carcasses and manure. ENVIRONMENTAL TECHNOLOGY 2020; 41:682-690. [PMID: 30080477 DOI: 10.1080/09593330.2018.1508256] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 07/28/2018] [Indexed: 06/08/2023]
Abstract
The present study evaluated anaerobic co-digestion of swine manure and swine carcasses for biogas yield and inactivation/behaviour of pathogens purpose. Biochemical Methane Production tests were performed with samples containing ratios of 3, 7.5 and 15 kgcarcass m-3 manure. For pathogens inactivation experiments known amounts of model microrganisms (sensitive and resistant) were artificially inoculated in anaerobic reactors at 24°C and 37°C. The addition of carcass resulted in an increase until 119% of biogas yield compared to swine manure mono-digestion. Salmonella enterica, Escherichia coli and PCV2 were reduced >3log10 (24°C or 37°C) during 30 days. At 37°C, MS2 and PhiX-174 were reduced 3log10 and 1.8log10, respectively. At 24°C, MS2 reduced 1.5 log10 and PhiX-174 did not present any decay over 30 days. Considering the most resistant biomarkers pathogens, as bacteriophage, we recommend the swine carcasses pre-treatment, such as high temperatures, for sanitary security.
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Rodrigues Oblessuc P, Vaz Bisneta M, Melotto M. Common and unique Arabidopsis proteins involved in stomatal susceptibility to Salmonella enterica and Pseudomonas syringae. FEMS Microbiol Lett 2019; 366:fnz197. [PMID: 31529017 PMCID: PMC7962777 DOI: 10.1093/femsle/fnz197] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 09/12/2019] [Indexed: 12/23/2022] Open
Abstract
Salmonella enterica is one of the most common pathogens associated with produce outbreaks worldwide; nonetheless, the mechanisms uncovering their interaction with plants are elusive. Previous reports demonstrate that S. enterica ser. Typhimurium (STm), similar to the phytopathogen Pseudomonas syringae pv. tomato (Pst) DC3000, triggers a transient stomatal closure suggesting its ability to overcome this plant defense and colonize the leaf apoplast. In order to discover new molecular players that function in the stomatal reopening by STm and Pst DC3000, we performed an Arabidopsis mutant screening using thermal imaging. Further stomatal bioassay confirmed that the mutant plants exo70h4-3, sce1-3, bbe8, stp1, and lsu2 have smaller stomatal aperture widths than the wild type Col-0 in response to STm 14028s. The mutants bbe8, stp1 and lsu2 have impaired stomatal movement in response to Pst DC3000. These findings indicate that EXO70H4 and SCE1 are involved in bacterial-specific responses, while BBE8, STP1, and LSU2 may be required for stomatal response to a broad range of bacteria. The identification of new molecular components of the guard cell movement induced by bacteria will enable a better understanding of the initial stages of plant colonization and facilitate targeted prevention of leaf contamination with harmful pathogens.
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Telenchana-Chimbo P, Barrera-Carmona C, Cevallos-Quintero E, Jiménez-Prieto F, Solórzano L, Soria C, Soria C. [Prevalence of osteoarticular infections by Enterobacteria producing extended-spectrum -lactamases]. ACTA ORTOPEDICA MEXICANA 2019; 33:232-236. [PMID: 32246593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
INTRODUCTION Infections of enterobacteria producing extended-spectrum -lactamases place a heavy burden on health systems. Little is known in osteoarticular infections, so this work studied the prevalence of these infections in a third-level hospital. MATERIAL AND METHODS Prevalence study in patients of a Traumatology Service during 2016, with infection criteria provided by the CDC in Atlanta, Georgia. The VITEK® 2 AST-N272 (bioMérieux) system was used for bacterial identification at the species level and for antimicrobial susceptibility tests. RESULTS 7.85% (n = 86) were reported with osteoarticular infections; 22.09% (n = 19) were by enterobacteria BLEEs. An average of 77.1 days of hospitalization (SD 37.7) (46-200 days); isolation of the microorganism occurred 15 days after entry. Sixteen (84.2%) patients had osteomyelitis, three (15.8%) had a prosthetic knee or hip infection. The average number of treatment days was 60 days (21-129 days). Eighteen patients (94.7%) were discharged with resolution of their infectious picture; one patient died with infection over aggregated pneumonia due to carbapenem-resistant K. pneumoniae. DISCUSSION The prevalence of osteoarticular infections by enterobacteria BLEEs could not be accurately calculated, but we consider it to be within what is expected, infection control measures require higher standards and there is a lack of development programs to use antimicrobials rationally to control the emergence of these pathologies.
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Ruotsalainen P, Penttinen R, Mattila S, Jalasvuori M. Midbiotics: conjugative plasmids for genetic engineering of natural gut flora. Gut Microbes 2019; 10:643-653. [PMID: 30951393 PMCID: PMC6866695 DOI: 10.1080/19490976.2019.1591136] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/19/2019] [Accepted: 02/28/2019] [Indexed: 02/03/2023] Open
Abstract
The possibility to modify gut bacterial flora has become an important goal, and various approaches are used to achieve desirable communities. However, the genetic engineering of existing microbes in the gut, which are already compatible with the rest of the community and host immune system, has not received much attention. Here, we discuss and experimentally evaluate the possibility to use modified and mobilizable CRISPR-Cas9-endocing plasmid as a tool to induce changes in bacterial communities. This plasmid system (briefly midbiotic) is delivered from bacterial vector into target bacteria via conjugation. Compared to, for example, bacteriophage-based applications, the benefits of conjugative plasmids include their independence of any particular receptor(s) on host bacteria and their relative immunity to bacterial defense mechanisms (such as restriction-modification systems) due to the synthesis of the complementary strand with host-specific epigenetic modifications. We show that conjugative plasmid in association with a mobilizable antibiotic resistance gene targeting CRISPR-plasmid efficiently causes ESBL-positive transconjugants to lose their resistance, and multiple gene types can be targeted simultaneously by introducing several CRISPR RNA encoding segments into the transferred plasmids. In the rare cases where the midbiotic plasmids failed to resensitize bacteria to antibiotics, the CRISPR spacer(s) and their adjacent repeats or larger regions were found to be lost. Results also revealed potential caveats in the design of conjugative engineering systems as well as workarounds to minimize these risks.
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Shepelin AP, Polosenko OV, Marchikhina II, Sholokhova LP, Azhermacheva NI, Ershova MG, Poletaeva ED. [Clinical trials of salmonella enrichment medium.]. Klin Lab Diagn 2019; 63:557-563. [PMID: 30735322 DOI: 10.18821/0869-2084-2018-63-9-557-563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 05/25/2018] [Indexed: 11/17/2022]
Abstract
Salmonella infections continue to be a serious problem in modern medicine. Being intestinal infections-associated pathogens, representatives of the genus Salmonella manifest themselves as pathogenic bacteria, especially in developing nosocomial infections. Given the polymorphism of clinical symptoms of salmonellosis, laboratory studies using bacteriological and serological methods are an important link in the diagnosis. In addition, the general prevention of salmonellosis includes measures to identify bacteria carriers, to ensure control over the incidence in farm animals and birds, food safety, etc. The list of nutrient media to isolate and identify Salmonella is lengthy and steadily extending, and the choice of specific media is largely relies on the nature of the material under study as well as on the idea of the potential availability of Salmonella bacteria in it, with research, diagnosis or epidemic situation being taken into account. The SRCAMB (Rospotrebnadzor) has designed two nutrient media allowing the enrichment and isolation Salmonella from various clinical samples. These are "Nutrient Medium for Enrichment of Salmonella, Dry (Magnesium medium) and "Nutrient Agar with Brilliant Green, Phenolic Red, Lactose and Sucrose, Dry (BPLS-FMH agar)." Growth and inhibitory properties of the new culture media produced by the SRCAMB and commercial domestic and foreign counterparts have been compared by using clinical material. Domestic nutrient media such as Magnesium medium and BPLS-FMH agar were proved to correspond to their commercial analogues when being used for enrichment, isolating and counting Salmonella bacteria in clinical specimens to have bacteriological control real data.
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Miniero Davies Y, Xavier de Oliveira MG, Paulo Vieira Cunha M, Soares Franco L, Pulecio Santos SL, Zanolli Moreno L, Túlio de Moura Gomes V, Zanolli Sato MI, Schiavo Nardi M, Micke Moreno A, Becker Saidenberg A, Rose Marques de Sá L, Knöbl T. Edwardsiella tarda outbreak affecting fishes and aquatic birds in Brazil. Vet Q 2019; 38:99-105. [PMID: 30668277 PMCID: PMC6830998 DOI: 10.1080/01652176.2018.1540070] [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] [Indexed: 11/06/2022] Open
Abstract
Background:Edwardsiella tarda infections are frequent causes of severe outbreaks in the fish farming industry besides representing possible zoonotic risks. However, naturally occurring outbreaks that affect various species besides fishes are seldom described. Aim: To report an outbreak of acute mortality caused by E. tarda affecting multiple species that inhabited a natural pond in the state of São Paulo, Brazil. Materials and methods: Three adult tilapias, three Mallard ducks and one Snow egret were necropsied and subjected to further microbiological tests. Gross and microscopic lesions were documented. The antibiotic susceptibility and phylogenetic similarities among fish and avian strains were also determined. The E. tarda species was confirmed through MALDI-TOF, partial sodB sequencing and phylogenetic analysis. Results: Macroscopical findings between the three species included intestinal dilatation, mucosal hyperaemia and mucous to liquid contents. Common histopathology findings included acute enteritis, increased number of intraepithelial lymphocytes with bacteria adhered to the intestinal epithelium and lymphoid depletion in the spleen. E. tarda was isolated from several organs from all affected species. The phylogeny employing amplified fragment length polymorphism (AFLP) of eleven strains revealed high similarity (>90%) among the isolates regardless of the affected species or sampled organs. Ten isolates of E. tarda showed susceptibility to all tested antibiotics. Conclusions:E. tarda was identified as the cause of death of the species examined. Further studies would be necessary to determine the virulence of these strains and the possible risks regarding public health.
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Yunusova RY, Gorelova VG, Kombarova SY, Aleshkin AV, Efimova OG, Bichucher AM, Martynenko IG, Alieva ER. [The development of Endo growth medium for detection and identification of enterobacteria.]. Klin Lab Diagn 2019; 63:110-113. [PMID: 30672676 DOI: 10.18821/0869-2084-2018-63-2-110-113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 10/20/2017] [Indexed: 11/17/2022]
Abstract
The purpose of study is to develop a traditional Endo's growth medium with the view of suppression of swarming of Proteus vulgaris and Proteus mirabilis. The object of study was a commercial dry Endo's growth medium. The inoculation of reference strains of enterobacteria and clinical sample (feces, urine, phlegm) was implemented according the normative documents. It is demonstrated that brining into Endo's growth medium tryptophan and sodium salts of bile acids in a particular ratio of their concentrations suppressed swarming of Proteus vulgaris and Proteus mirabilis. The obtained results demonstrated that application of enhanced Endo's growth medium significantly increases its differential and diagnostic characteristics.
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De Roos J, De Vuyst L. Microbial acidification, alcoholization, and aroma production during spontaneous lambic beer production. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2019; 99:25-38. [PMID: 30246252 DOI: 10.1002/jsfa.9291] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/04/2018] [Accepted: 07/25/2018] [Indexed: 05/18/2023]
Abstract
Acidic beers, such as Belgian lambic beers and American and other coolship ales, are becoming increasingly popular worldwide thanks to their refreshing acidity and fruity notes. The traditional fermentation used to produce them does not apply pure yeast cultures but relies on spontaneous, environmental inoculation. The fermentation and maturation process is carried out in wooden barrels and can take up to three years. It is characterized by different microbial species belonging to the enterobacteria, acetic acid bacteria, lactic acid bacteria, and yeasts. This review provides an introduction to the technology and four fermentation strategies of beer production, followed by the microbiology of acidic beer production, focusing on the main microorganisms present during the long process used for the production of Belgian lambic beers. © 2018 Society of Chemical Industry.
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Marotta SM, Giarratana F, Calvagna A, Ziino G, Giuffrida A, Panebianco A. Study on microbial communities in domestic kitchen sponges: Evidence of Cronobacter sakazakii and Extended Spectrum Beta Lactamase (ESBL) producing bacteria. Ital J Food Saf 2018; 7:7672. [PMID: 30854338 PMCID: PMC6379783 DOI: 10.4081/ijfs.2018.7672] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 11/12/2018] [Indexed: 01/03/2023] Open
Abstract
Domestic environment, in particular, kitchen setting is a well-established source of microbial contamination. Kitchen sponges represent an important vehicle of microbial transmission and maintenance of spoilage bacteria and pathogenic strains responsible for food borne diseases. The aim of this study was to evaluate the microbial communities of 100 'in-use' kitchen sponges, improving the knowledge on their role in cross-contamination in domestic environment and transmission of ESBLproducing strains. Sponges were processed for: aerobic mesophilic bacteria (AMB), Enterobacteriaceae (EB), yeasts and molds (YM), coagulase-positive staphylococci (CPS), micrococci (MCC), anaerobic sulfite reducing bacteria (ASR), and for the detection of Listeria monocytogenes, Salmonella spp. and Yersinia enterocolitica. A total of 309 enterobacteria strains were identified and then processed for ESBL (Extended Spectrum Beta Lactamase) phenotypical expression. A high contamination level of kitchen sponges was observed (mean value AMB 8.25±1.1; EB 5.89±1.2; YM 5.57±1.1; MCC 4.82±0.1 log CFU/g). Identified enterobacteria strains revealed several opportunistic and pathogenic agents such as Enterobacter cloacae (28%), Citrobacter freundii (23.3%), Cronobacter sakazakii (14.6%) and other strains in lower percentage. Listeria monocytogenes was found in only one sponge (1%). A total of 69 (22.3%) enterobacteria resulted ESBL+, with the following prevalence: P. rettgeri (50%), L. adenocarboxilata (30%), K. pneumoniae (25%), K. oxytoca (25%), C. sakazakii (20%), E. cloacae (20.7%), C. freundii (20.1%). Results confirm the potential role of kitchen sponges as vehicle for food-borne pathogens such as, C. sakazakii for the first time, infectious agents and spoilage microorganisms. The observed high contamination level and the presence of several ESBLs opportunistic pathogens, stresses the necessity to improve a proper education of the consumers on the effective treatment to reduce their microbial loads.
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Qi B, Han M. Microbial Siderophore Enterobactin Promotes Mitochondrial Iron Uptake and Development of the Host via Interaction with ATP Synthase. Cell 2018; 175:571-582.e11. [PMID: 30146159 DOI: 10.1016/j.cell.2018.07.032] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 06/18/2018] [Accepted: 07/23/2018] [Indexed: 02/09/2023]
Abstract
Elucidating the benefits of individual microbiota-derived molecules in host animals is important for understanding the symbiosis between humans and their microbiota. The bacteria-secreted enterobactin (Ent) is an iron scavenging siderophore with presumed negative effects on hosts. However, the high prevalence of Ent-producing commensal bacteria in the human gut raises the intriguing question regarding a potential host mechanism to beneficially use Ent. We discovered an unexpected and striking role of Ent in supporting growth and the labile iron pool in C. elegans. We show that Ent promotes mitochondrial iron uptake and does so, surprisingly, by binding to the ATP synthase α subunit, which acts inside of mitochondria and independently of ATP synthase. We also demonstrated the conservation of this mechanism in mammalian cells. This study reveals a distinct paradigm for the "iron tug of war" between commensal bacteria and their hosts and an important mechanism for mitochondrial iron uptake and homeostasis.
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Imade OS, Akinnibosun FI. The Nigerian catfish (Clarias gariepinus) pisciculture systems: reservoirs of multidrug-resistant bacteria. J Appl Microbiol 2018; 125:1552-1568. [PMID: 30066443 DOI: 10.1111/jam.14056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 07/21/2018] [Accepted: 07/23/2018] [Indexed: 11/30/2022]
Abstract
AIM Control of operations of catfish farmers still lacks in Nigeria due to the absence of catfish inspection programmes by relevant regulatory agencies. Thus, this study aimed at performing comprehensive surveillance of Nigerian catfish pisciculture systems so as to provide empirical evidence on the extent of contamination with multidrug-resistant bacteria due to potential abuse of standard operational procedures by catfish farmers. METHODS AND RESULTS One-way analysis of variance was performed on pond water and catfish samples which were randomized with the Wei's-Urn randomization modelling technique. Ceftriaxone-selected bacterial colonies isolated from catfish and pond water samples collected from nursery and grow-out pond systems were tested for multidrug resistance. Haemocytotoxigenic and Shiga toxigenic virulence traits in multidrug-resistant colonies, as well as detection of hyper-Ambler class C-(AmpC) beta-lactamase and carbapenemase production, were also performed using phenotypic/molecular methods. Of the 648 ceftriaxone-selected bacterial isolates examined in this study, 515 isolates were found to be multidrug-resistant bacteria, of which 366 isolates were characterized as pathogenic multidrug-resistant bacteria. Both nursery and grow-out ponds had high frequencies of bacterial resistance to ampicillin (86-93%), cotrimoxazole (47-87%) and chloramphenicol (95-100%). However, high frequencies of bacterial resistance to amoxicillin/clavulanic acid (75-83%) were only observed in the grow-out ponds. Also, hyper-AmpC beta-lactamase-producing multidrug-resistant bacteria were only seen in the grow-out ponds. Isolated multidrug-resistant bacteria were confirmed as Enterobacter cloacae, Citrobacter freundii, Bacillus cereus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus faecalis. CONCLUSION The findings in this study corroborate the urgent need for some form of international mediation to urge the Nigerian government and her regulatory agencies to commence monitoring of catfish pisciculture operations since multidrug-resistant bacteria could be transmitted to humans. SIGNIFICANCE AND IMPACT OF THE STUDY Our study provided empirical evidence that revealed the misuse/abuse of antibiotics during pisciculture operations in Nigeria; thus, constituting these pisciculture systems into reservoirs of multidrug-resistant bacteria.
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Takeuchi K, Komatsu Y, Nakamori Y, Kotani T. A Rat Model of Ischemic Enteritis: Pathogenic Importance of Enterobacteria, iNOS/NO, and COX-2/PGE2. Curr Pharm Des 2018; 23:4048-4056. [PMID: 28228071 DOI: 10.2174/1381612823666170220154815] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 02/02/2017] [Accepted: 02/13/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND We introduced a rat model of ischemic enteritis and investigated the roles of enterobacteria, Nitric Oxide (NO), and Prostaglandins (PGs) in its pathogenesis. METHODS Male rats were used after 18 h of fasting. Ischemic enteritis was induced by partial ligation of the superior mesenteric artery (SMA). Under ether anesthesia, SMA was isolated, and a stenosis was made by placing a needle (23 guage) on the vessel and ligating both the vessel and needle, and then a needle was removed from the ligature. Animals were then fed normally after surgery. Various drugs such as antibiotics, cyclooxygenase (COX) inhibitors, NO synthase (NOS) inhibitors and PGE2 were administered for 2 days after surgery. RESULTS Stenosis of the SMA caused mucosal ischemia and damaged the small intestine, particularly the ileum, within 3 days. The development of enteritis was accompanied by mucosal invasion of enterobacteria, with the bacterial count being significantly increased 8 h after surgery. The severity of enteritis was prevented by the prior administration of ampicillin, L-NAME, or aminoguanidine, but aggravated by that of indomethacin or rofecoxib. The deleterious effects of indomethacin were antagonized by the co-administration of PGE2; these effects were mimicked by AE1-329, an EP4 agonist, and abrogated by AE3-208, an EP4 antagonist. The expression of iNOS and COX-2 was up-regulated in the small intestine in a time-dependent manner after ischemia caused by stenosis of the SMA, with increases in the mucosal contents of NO and PGE2. CONCLUSION These results suggest that enterobacteria played a major pathogenic role in this model of ischemic enteritis, and that iNOS/NO was deleterious in the pathogenesis of these lesions, while COX-2/PGE2 prevented the development of ischemic enteritis by activating EP4 receptors.
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Aghraz A, Benameur Q, Gervasi T, Ait Dra L, Ben-Mahdi MH, Larhsini M, Markouk M, Cicero N. Antibacterial activity of Cladanthus arabicus and Bubonium imbricatum essential oils alone and in combination with conventional antibiotics against Enterobacteriaceae isolates. Lett Appl Microbiol 2018; 67:175-182. [PMID: 29763981 DOI: 10.1111/lam.13007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 05/01/2018] [Accepted: 05/02/2018] [Indexed: 11/30/2022]
Abstract
Multidrug-resistant bacteria have become common all over the world, necessitating the development of new therapeutic strategies. Synergistic interactions between conventional antibiotics and natural bioactive may have therapeutic benefits in a clinical setting. There are plenty of medicinal plants that have proven efficacy against broad spectrum of micro-organisms. The aim of the work was to assess the antibacterial activity of Cladanthus arabicus, a Moroccan medicinal plant, and Bubonium imbricatum, a Moroccan endemic plant. The evaluation of the synergistic effect of extracted essential oils (EOs) together with some conventional antibiotics was also investigated. Checkerboard test was used to evaluate the interaction of EOs in combination with amoxicillin and neomycin. The results showed that EOs contain a potent activity against the tested Enterobacteriaceae isolates, with inhibition zones values in the range of 8·05 ± 0·1 and 13·1 ± 0·11 mm and MIC values between 200 μg ml-1 to 800 μg ml-1 for C. arabicus and from 400 μg ml-1 to 1600 μg ml-1 for B. imbricatum, respectively. Moreover, the current study allowed concluding that both EOs showed not only satisfactory antibacterial properties but also active effects combined with conventional antibiotics demonstrated by the Fractional Inhibitory Concentration Index (FICI). These findings are very interesting since there are no previous studies on synergistic interactions of these two plants with antibiotics. SIGNIFICANCE AND IMPACT OF THE STUDY The development of antibiotic resistance is multifactorial, including the specific nature of the relationship of bacteria to antibiotics. This situation has forced scientists to search for new antimicrobial substances from various sources as novel antimicrobial chemotherapeutic agents. Recently, medicinal plants and their derivatives (essential oils, extracts) have become very important in therapeutics because they encounter minimal challenges of the emergence of resistance. In this direction, the antimicrobial activity of the endemic Bubonium imbricatum plant and medicinal Cladanthus arabicus plant essential oils against multidrug-resistant Enterobacteriaceae strains was demonstrated.
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