WorldWideScience

Sample records for isolated microbial pathogens

  1. Antimicrobial effect of Calotropis procera active principles against aquatic microbial pathogens isolated from shrimp and fishes

    Institute of Scientific and Technical Information of China (English)

    Subramanian Velmurugan; Vijayaragavan Thanga Viji; Mariavincent Michael Babu; Mary Josephine Punitha; Thavasimuthu Citarasu

    2012-01-01

    Objective: To study the influence of Calotropis procera (C. procera) active principles against aquatic microbial pathogens isolated from shrimp and fishes. Methods: C. procera leaf powder was serially extracted with hexane, ethyl acetate and methanol and screened by antibacterial, antifungal and antiviral activity against aquatic pathogens which isolated from shrimp/fish. After initial screening, the active extract was purified through column chromatography and again screened. Finally the active fractions were characterized by phytochemical analysis and GC-MS analysis. Results: In vitro antibacterial, antifungal and antiviral screening revealed that, the ethyl acetate extracts were effectively suppressed the bacterial pathogens Pseudomonas aeruginosa (P. aeruginosa), Vibrio harveyi (V. harveyi) and Aeromons hydrophila (A. hydrophila) of more than 20 mm zone of inhibition; the fungi Fusarium sp and the killer virus WSSV. The ethyl acetate extracts of C. procera incubated WSSV was failed to multiply its progeny in the in vivo system of shrimp P. monodon. The shrimp had 80% survival after WSSV challenge from the control group significantly (P<0.001) and also PCR detection confirmed that no WSSV transcription found in shrimp haemolymph. After purified the ethyl acetate extracts again antimicrobial screening performed and it concluded that the fraction namely F-II was effectively suppressed the bacterial growth and WSSV due to its enriched active principles such as cardiac glycosides, Phenols, alkaloids, Tannin and quinines. Surprisingly this fraction, F-II was effectively controlled the WSSV at 90% level at a highest significant level (P<0.001). Finally the structural characterization by GC-MS analysis revealed that, the F-II fraction contained Phenols including several other compounds such as 2,4-bis(1,1-dimethylethyl)-, Methyl tetradecanoate, Bicyclo[3.1.1] heptane, 2,6,6-trimethyl-, (1α,2β,5α)-and Hexadecanoic acid etc. Conclusions: The present study revealed

  2. Evolution of microbial pathogens

    National Research Council Canada - National Science Library

    DiRita, Victor J; Seifert, H. Steven

    2006-01-01

    ... A. Hogan vvi ■ CONTENTS 8. Evolution of Pathogens in Soil Rachel Muir and Man-Wah Tan / 131 9. Experimental Models of Symbiotic Host-Microbial Relationships: Understanding the Underpinnings of ...

  3. MICROBIAL LOAD AND MULTIPLE DRUG RESISTANCE OF PATHOGENIC BACTERIA ISOLATED FROM FEACES AND BODY SURFACES OF COCKROACHES IN AN URBAN AREA OF SOUTHWESTERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Monsuru Adebayo Adeleke

    2012-06-01

    Full Text Available This study investigates the microbial load and antibiotic susceptibility pattern of pathogenic bacteria isolated from the faeces and body surfaces of cockroaches in Osogbo, Southwestern Nigeria. The cockroaches collected from residential areas and hospital vicinities were screened for microbial load and antibiotic susceptibility pattern using standard protocols. A total of twenty- three microorganisms namely Klebsiella aerogenes, Bacillius cereus, Proteus spp, Staphyloccocus aureus, S. saprophyticus, Enteroccocus faecalis, Staphylococus epididermis, E. coli, Listeria monoctogene, Proteus mirabilis, Citrobacter species, Pseudomonas aeruginosa, Psuedomonas species, Seretia mensence, Candida albicans, Candida spp., Aspergilius spp., A. flavus, A. fumigates, Mucor species and Penicilium species were isolated. The microbial load of the microorganisms was significantly higher in the isolates from hospital as compared with the residential area (p<0.05 with the exception of Canidida species, Mucor and Penicillium which had higher or equal microbial load at the residential areas. All the pathogenic bacteria isolated had multiple resistance to antibiotics most importantly, Ampicillin, Augumentin, Amoxicillin and Septrin (30μg. Efforts geared towards controlling the insects will be indispensable in curbing the wide spread of multi-drug resistant pathogens in the study area.

  4. Genome analysis of multiple pathogenic isolates of Streptococcus agalactiae : Implications for the microbial "pan-genome"

    NARCIS (Netherlands)

    Tettelin, H; Masignani, [No Value; Cieslewicz, MJ; Donati, C; Medini, D; Ward, NL; Angiuoli, SV; Crabtree, J; Jones, AL; Durkin, AS; DeBoy, RT; Davidsen, TM; Mora, M; Scarselli, M; Ros, IMY; Peterson, JD; Hauser, CR; Sundaram, JP; Nelson, WC; Madupu, R; Brinkac, LM; Dodson, RJ; Rosovitz, MJ; Sullivan, SA; Daugherty, SC; Haft, DH; Selengut, J; Gwinn, ML; Zhou, LW; Zafar, N; Khouri, H; Radune, D; Dimitrov, G; Watkins, K; O'Connor, KJB; Smith, S; Utterback, TR; White, O; Rubens, CE; Grandi, G; Madoff, LC; Kasper, DL; Telford, JL; Wessels, MR; Rappuoli, R; Fraser, CM

    2005-01-01

    The development of efficient and inexpensive genome sequencing methods has revolutionized the study of human bacterial pathogens and improved vaccine design. Unfortunately, the sequence of a single genome does not reflect how genetic variability drives pathogenesis within a bacterial species and

  5. ANTIMICROBIAL SUSCEPTIBILITY PROFILE OF MICROBIAL PATHOGENS ISOLATED FROM CALVES WITH RESPIRATORY DISEASES

    OpenAIRE

    George Cosmin Nadas; Flore Chirila; Cosmina Bouari; Nicodim Fit

    2016-01-01

    Introduction: Respiratory disease in calves is an actual problem, a major cause of economic losses due to mortality, growth delay and improper development. These conditions are frequent in calves due to the weaning stress, transport and environmental changes. Aims: The aim of this study was the isolation of bacteria from 30 calves with respiratory disorders and their antibiotic susceptibility testing. Materials and methods: Samples were collected from calves with respiratory disorders...

  6. ANTIMICROBIAL SUSCEPTIBILITY PROFILE OF MICROBIAL PATHOGENS ISOLATED FROM CALVES WITH RESPIRATORY DISEASES

    Directory of Open Access Journals (Sweden)

    George Cosmin Nadas

    2016-11-01

    Full Text Available Introduction: Respiratory disease in calves is an actual problem, a major cause of economic losses due to mortality, growth delay and improper development. These conditions are frequent in calves due to the weaning stress, transport and environmental changes. Aims: The aim of this study was the isolation of bacteria from 30 calves with respiratory disorders and their antibiotic susceptibility testing. Materials and methods: Samples were collected from calves with respiratory disorders (nasal discharge aged 6 to 9 weeks in 2 series, using sterile swabs. Samples were initially inoculated on blood agar and MacConkey agar following the characteristics of the colonies and microscopic examination that enabled the identification of bacterial species. Isolated strains were used to flood Mueller-Hinton agar to carry out sensitivity testing. The antibiotics tested were represented by: Amoxicillin with clavulanic acid, Gentamicin, Florfenicol, Enrofloxacin, Marbofloxacin, Penicillin G, Cefquinone, Tulathromycin, Ceftiofur, Tylosin and Cephalotin. Results: Genus Streptococcus have been identified in 23 samples, followed by Staphylococcus identified in 14 samples, and Bacillus spp., in 10 nasal swabs; The most common bacteria associations were represented by Streptococcus-Staphylococcus, Streptococcus-Staphylococcus-Bacillus, and Streptococcus-E.coli. The most efficient antibiotic was Cefquinome (Cobactan, followed by Penicillin G and Amoxicillin with clavulanic acid (Amoxiclav; the least effective antibiotics were Florfenicol and Tulathromycin. Conclusions: The study carried out on nasal discharge samples collected from calves with respiratory disorders and their antimicrobial profile testing led to the following conclusions: 1 Low susceptibility to Florfenicol is caused by previous treatments when this molecule was excessively used and without prior sensitivity testing. 2 Cefquinome may represent an emergency therapeutic antibiotic for respiratory

  7. Evolution of microbial pathogens.

    OpenAIRE

    Morschhäuser, J; Köhler, G; Ziebuhr, W; Blum-Oehler, G; Dobrindt, U; Hacker, J

    2000-01-01

    Various genetic mechanisms including point mutations, genetic rearrangements and lateral gene transfer processes contribute to the evolution of microbes. Long-term processes leading to the development of new species or subspecies are termed macroevolution, and short-term developments, which occur during days or weeks, are considered as microevolution. Both processes, macro- and microevolution need horizontal gene transfer, which is particularly important for the development of pathogenic micr...

  8. Antibiotics susceptibility patterns of bacteria isolated from American and German cockroaches as potential vectors of microbial pathogens in hospitals

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Fakoorziba

    2014-09-01

    Full Text Available Objective: To identify the cockroach species, their bacterial flora and antibiotics susceptibility patterns of these bacteria in Shiraz. Methods: In the present descriptive study, only two species of cockroaches were recognized. The washing solutions from the digestion systems and surfaces of 156 American and German cockroaches were cultured. The latter was found to be the commonest (89.7% in all places. Results: Overall, 18 species of bacteria were isolated and identified by standard culture methods. The most frequent bacterium isolated from both species of cockroaches in all places was Pseudomonas (41.7%. The second and third commonest bacteria were Enterobacter (39.7% and Klebsiella (32.7%, respectively. Conclusions: The antibiogram profiles showed full (100% resistance of Klebsiella, Citrobacter, Acinetobacter and Proteus to amoxicillin and ampicillin at both hospitals, while Pseudomonas showed resistance (95.7% to cephalothin. Thus it is concluded that German and American cockroaches carry multidrug resistant bacteria in two hospitals which raises alarm for stricter control measures.

  9. Adaptive value of sex in microbial pathogens.

    Science.gov (United States)

    Michod, Richard E; Bernstein, Harris; Nedelcu, Aurora M

    2008-05-01

    Explaining the adaptive value of sex is one of the great outstanding problems in biology. The challenge comes from the difficulty in identifying the benefits provided by sex, which must outweigh the substantial costs of sex. Here, we consider the adaptive value of sex in viruses, bacteria and fungi, and particularly the information available on the adaptive role of sex in pathogenic microorganisms. Our general theme is that the varied aspects of sex in pathogens illustrate the varied issues surrounding the evolution of sex generally. These include, the benefits of sex (in the short- and long-term), as well as the costs of sex (both to the host and to the pathogen). For the benefits of sex (that is, its adaptive value), we consider three hypotheses: (i) sex provides for effective and efficient recombinational repair of DNA damages, (ii) sex provides DNA for food, and (iii) sex produces variation and reduces genetic associations among alleles under selection. Although the evolution of sex in microbial pathogens illustrates these general issues, our paper is not a general review of theories for the evolution of sex in all organisms. Rather, we focus on the adaptive value of sex in microbial pathogens and conclude that in terms of short-term benefits, the DNA repair hypothesis has the most support and is the most generally applicable hypothesis in this group. In particular, recombinational repair of DNA damages may substantially benefit pathogens when challenged by the oxidative defenses of the host. However, in the long-term, sex may help get rid of mutations, increase the rate of adaptation of the population, and, in pathogens, may infrequently create new infective strains. An additional general issue about sex illustrated by pathogens is that some of the most interesting consequences of sex are not necessarily the reasons for which sex evolved. For example, antibiotic resistance may be transferred by bacterial sex, but this transfer is probably not the reason sex

  10. Microbial and viral pathogens in colorectal cancer.

    LENUS (Irish Health Repository)

    Collins, Danielle

    2011-05-01

    The heterogenetic and sporadic nature of colorectal cancer has led to many epidemiological associations with causes of this disease. As our understanding of the underlying molecular processes in colorectal-cancer develops, the concept of microbial-epithelial interactions as an oncogenic trigger might provide a plausible hypothesis for the pathogenesis of colorectal cancer. By contrast with other cancers of the gastrointestinal tract (gastric carcinoma, mucosa-associated lymphoid-tissue lymphoma), a direct causal link between microbial infection (bacteria and viruses) and colorectal carcinoma has not been established. Studies support the involvement of these organisms in oncogenesis, however, in colorectal cancer, clinical data are lacking. Here, we discuss current evidence (both in vitro and clinical studies), and focus on a putative role for bacterial and viral pathogens as a cause of colorectal cancer.

  11. Microbial and viral pathogens in colorectal cancer.

    LENUS (Irish Health Repository)

    Collins, Danielle

    2012-02-01

    The heterogenetic and sporadic nature of colorectal cancer has led to many epidemiological associations with causes of this disease. As our understanding of the underlying molecular processes in colorectal-cancer develops, the concept of microbial-epithelial interactions as an oncogenic trigger might provide a plausible hypothesis for the pathogenesis of colorectal cancer. By contrast with other cancers of the gastrointestinal tract (gastric carcinoma, mucosa-associated lymphoid-tissue lymphoma), a direct causal link between microbial infection (bacteria and viruses) and colorectal carcinoma has not been established. Studies support the involvement of these organisms in oncogenesis, however, in colorectal cancer, clinical data are lacking. Here, we discuss current evidence (both in vitro and clinical studies), and focus on a putative role for bacterial and viral pathogens as a cause of colorectal cancer.

  12. PATHOGENIC POTENTIALS OF ESCHERICHIA COLI ISOLATED ...

    African Journals Online (AJOL)

    Electrolyte and haematological parameters in rabbits infected with pathogenic isolates of Escherichia coli from rural water supplies in Rivers State, Nigeria, where monitored. Rabbits were orally infected with suspension containing 3x107 cfu /ml of Escherichia coli to induce diarrhoea, and the electrolyte (sodium, potassium ...

  13. Microbial antagonism as a potential solution for controlling selected root pathogens of crops

    Science.gov (United States)

    Cooper, Sarah; Agnew, Linda; Pereg, Lily

    2016-04-01

    Root pathogens of crops can cause large reduction in yield, however, there is a limited range of effective methods to control such pathogens. Soilborne pathogens that infect roots often need to survive in the rhizosphere, where there is high competition from other organisms. In such hot spots of microbial activity and growth, supported by root exudates, microbes have evolved antagonistic mechanisms that give them competitive advantages in winning the limited resources. Among these mechanisms is antibiosis, with production of some significant antifungal compounds including, antibiotics, volatile organic compounds, hydrogen cyanide and lytic enzymes. Some of these mechanisms may suppress disease through controlling the growth of root pathogens. In this project we isolated various fungi and bacteria that suppress the growth of cotton pathogens in vitro. The pathogen-suppressive microbes were isolated from cotton production soils that are under different management strategies, with and without the use of organic amendments. The potential of pathogen-suppressing microbes for controlling the black root rot disease, caused by the soilborne pathogen Thielaviopsis basicola, was confirmed using soil assays. We identified isolates with potential use as inoculant for cotton production in Australia. Having isolated a diverse group of antagonistic microbes enhances the probability that some would survive well in the soil and provide an alternative approach to address the problem of root disease affecting agricultural crops.

  14. Microbial minimalism: genome reduction in bacterial pathogens.

    Science.gov (United States)

    Moran, Nancy A

    2002-03-08

    When bacterial lineages make the transition from free-living or facultatively parasitic life cycles to permanent associations with hosts, they undergo a major loss of genes and DNA. Complete genome sequences are providing an understanding of how extreme genome reduction affects evolutionary directions and metabolic capabilities of obligate pathogens and symbionts.

  15. Emerging microbial biocontrol strategies for plant pathogens.

    Science.gov (United States)

    Syed Ab Rahman, Sharifah Farhana; Singh, Eugenie; Pieterse, Corné M J; Schenk, Peer M

    2018-02-01

    To address food security, agricultural yields must increase to match the growing human population in the near future. There is now a strong push to develop low-input and more sustainable agricultural practices that include alternatives to chemicals for controlling pests and diseases, a major factor of heavy losses in agricultural production. Based on the adverse effects of some chemicals on human health, the environment and living organisms, researchers are focusing on potential biological control microbes as viable alternatives for the management of pests and plant pathogens. There is a growing body of evidence that demonstrates the potential of leaf and root-associated microbiomes to increase plant efficiency and yield in cropping systems. It is important to understand the role of these microbes in promoting growth and controlling diseases, and their application as biofertilizers and biopesticides whose success in the field is still inconsistent. This review focusses on how biocontrol microbes modulate plant defense mechanisms, deploy biocontrol actions in plants and offer new strategies to control plant pathogens. Apart from simply applying individual biocontrol microbes, there are now efforts to improve, facilitate and maintain long-term plant colonization. In particular, great hopes are associated with the new approaches of using "plant-optimized microbiomes" (microbiome engineering) and establishing the genetic basis of beneficial plant-microbe interactions to enable breeding of "microbe-optimized crops". Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Investigating the Swimming of Microbial Pathogens Using Digital Holography.

    Science.gov (United States)

    Thornton, K L; Findlay, R C; Walrad, P B; Wilson, L G

    2016-01-01

    To understand much of the behaviour of microbial pathogens, it is necessary to image living cells, their interactions with each other and with host cells. Species such as Escherichia coli are difficult subjects to image: they are typically microscopic, colourless and transparent. Traditional cell visualisation techniques such as fluorescent tagging or phase-contrast microscopy give excellent information on cell behaviour in two dimensions, but no information about cells moving in three dimensions. We review the use of digital holographic microscopy for three-dimensional imaging at high speeds, and demonstrate its use for capturing the shape and swimming behaviour of three important model pathogens: E. coli, Plasmodium spp. and Leishmania spp.

  17. Differential Microbial Diversity in Drosophila melanogaster: Are Fruit Flies Potential Vectors of Opportunistic Pathogens?

    Directory of Open Access Journals (Sweden)

    Luis A. Ramírez-Camejo

    2017-01-01

    Full Text Available Drosophila melanogaster has become a model system to study interactions between innate immunity and microbial pathogens, yet many aspects regarding its microbial community and interactions with pathogens remain unclear. In this study wild D. melanogaster were collected from tropical fruits in Puerto Rico to test how the microbiota is distributed and to compare the culturable diversity of fungi and bacteria. Additionally, we investigated whether flies are potential vectors of human and plant pathogens. Eighteen species of fungi and twelve species of bacteria were isolated from wild flies. The most abundant microorganisms identified were the yeast Candida inconspicua and the bacterium Klebsiella sp. The yeast Issatchenkia hanoiensis was significantly more common internally than externally in flies. Species richness was higher in fungi than in bacteria, but diversity was lower in fungi than in bacteria. The microbial composition of flies was similar internally and externally. We identified a variety of opportunistic human and plant pathogens in flies such as Alcaligenes faecalis, Aspergillus flavus, A. fumigatus, A. niger, Fusarium equiseti/oxysporum, Geotrichum candidum, Klebsiella oxytoca, Microbacterium oxydans, and Stenotrophomonas maltophilia. Despite its utility as a model system, D. melanogaster can be a vector of microorganisms that represent a potential risk to plant and public health.

  18. The Microbial DNA Index System (MiDIS): A tool for microbial pathogen source identification

    Energy Technology Data Exchange (ETDEWEB)

    Velsko, S. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-08-09

    The microbial DNA Index System (MiDIS) is a concept for a microbial forensic database and investigative decision support system that can be used to help investigators identify the sources of microbial agents that have been used in a criminal or terrorist incident. The heart of the proposed system is a rigorous method for calculating source probabilities by using certain fundamental sampling distributions associated with the propagation and mutation of microbes on disease transmission networks. This formalism has a close relationship to mitochondrial and Y-chromosomal human DNA forensics, and the proposed decision support system is somewhat analogous to the CODIS and SWGDAM mtDNA databases. The MiDIS concept does not involve the use of opportunistic collections of microbial isolates and phylogenetic tree building as a basis for inference. A staged approach can be used to build MiDIS as an enduring capability, beginning with a pilot demonstration program that must meet user expectations for performance and validation before evolving into a continuing effort. Because MiDIS requires input from a a broad array of expertise including outbreak surveillance, field microbial isolate collection, microbial genome sequencing, disease transmission networks, and laboratory mutation rate studies, it will be necessary to assemble a national multi-laboratory team to develop such a system. The MiDIS effort would lend direction and focus to the national microbial genetics research program for microbial forensics, and would provide an appropriate forensic framework for interfacing to future national and international disease surveillance efforts.

  19. Sexual reproduction and the evolution of microbial pathogens.

    Science.gov (United States)

    Heitman, Joseph

    2006-09-05

    Three common systemic human fungal pathogens--Cryptococcus neoformans, Candida albicans and Aspergillus fumigatus--have retained all the machinery to engage in sexual reproduction, and yet their populations are often clonal with limited evidence for recombination. Striking parallels have emerged with four protozoan parasites that infect humans: Toxoplasma gondii, Trypanosoma brucei, Trypanosoma cruzi and Plasmodium falciparum. Limiting sexual reproduction appears to be a common virulence strategy, enabling generation of clonal populations well adapted to host and environmental niches, yet retaining the ability to engage in sexual or parasexual reproduction and respond to selective pressure. Continued investigation of the sexual nature of microbial pathogens should facilitate both laboratory investigation and an understanding of the complex interplay between pathogens, hosts, vectors, and their environments.

  20. Pathogenic Vibrio parahaemolyticus isolated from biofouling on commercial vessels and harbor structures.

    Science.gov (United States)

    Revilla-Castellanos, Valeria J; Guerrero, Abraham; Gomez-Gil, Bruno; Navarro-Barrón, Erick; Lizárraga-Partida, Marcial L

    2015-01-01

    Ballast water is a significant vector of microbial dissemination; however, biofouling on commercial vessel hulls has been poorly studied with regard to pathogenic bacteria transport. Biofouling on three commercial vessels and seven port structures in Ensenada, Baja California, Mexico, was examined by qPCR to identify and quantify Vibrio parahaemolyticus, a worldwide recognized food-borne human pathogen. Pathogenic variants (trh+, tdh+) of V. parahaemolyticus were detected in biofouling homogenates samples from several docks in Ensenada and on the hulls of ships with Japanese and South Korean homeports, but not in reference sampling stations. A total of 26 tdh+ V. parahaemolyticus colonies and 1 ORF8+/O3:K6 strain were also isolated from enriched biofouling homogenate samples confirming the qPCR analysis. Our results suggest that biofouling is an important reservoir of pathogenic vibrios. Thus, ship biofouling might be an overlooked vector with regard to the dissemination of pathogens, primarily pathogenic V. parahaemolyticus.

  1. Whey protein isolate/cellulose nanofibre/TiO2 nanoparticle/rosemary essential oil nanocomposite film: Its effect on microbial and sensory quality of lamb meat and growth of common foodborne pathogenic bacteria during refrigeration.

    Science.gov (United States)

    Alizadeh Sani, Mahmood; Ehsani, Ali; Hashemi, Mohammad

    2017-06-19

    The use of biodegradable nanocomposite films in active packaging is of great importance since they can have a controlled release of antimicrobial compounds. This study was conducted to evaluate the efficacy of whey protein isolate (WPI)/cellulose nanofibre (CNF) nanocomposite films containing 1.0% (w/w) titanium dioxide (TiO 2 ) and 2.0% (w/v) rosemary essential oil (REO) in preserving the microbial and sensory quality of lamb meat during the storage at 4±1°C. Initially, the best concentration of each compound to be added to the film was determined by micro-dilution and disc diffusion methods. The microbial and sensory properties of lamb meat were controlled in two groups (control and treatment) over 15days of storage. Then, the samples were analysed for total viable count (TVC), Pseudomonas spp. count, Enterobacteriaceae count, Lactic acid bacteria (LAB) count, inoculated Staphylococcus aureus count, Listeria monocytogenes count, and Escherichia coli O 157 :H 7 count. Microbial analysis and nine-point hedonic scale was applied for the sensory analysis. Results indicated that the use of nanocomposite films significantly reduced the bacterial counts of treatment group. Higher inhibition effect was observed on Gram-positive bacteria than on Gram-negative bacteria (Psensory evaluations also showed that the use of nanocomposite films significantly increased the shelf life of treated meat (15days) compared to the control meat (6days). Based on the results of this study, the edible nanocomposite films were effective in preserving the microbial and sensory qualities of lamb meat; therefore, this application is recommended in meat especially red meat. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Sequestered Alkaloid Defenses in the Dendrobatid Poison Frog Oophaga pumilio Provide Variable Protection from Microbial Pathogens.

    Science.gov (United States)

    Hovey, Kyle J; Seiter, Emily M; Johnson, Erin E; Saporito, Ralph A

    2018-03-01

    Most amphibians produce their own defensive chemicals; however, poison frogs sequester their alkaloid-based defenses from dietary arthropods. Alkaloids function as a defense against predators, and certain types appear to inhibit microbial growth. Alkaloid defenses vary considerably among populations of poison frogs, reflecting geographic differences in availability of dietary arthropods. Consequently, environmentally driven differences in frog defenses may have significant implications regarding their protection against pathogens. While natural alkaloid mixtures in dendrobatid poison frogs have recently been shown to inhibit growth of non-pathogenic microbes, no studies have examined the effectiveness of alkaloids against microbes that infect these frogs. Herein, we examined how alkaloid defenses in the dendrobatid poison frog, Oophaga pumilio, affect growth of the known anuran pathogens Aeromonas hydrophila and Klebsiella pneumoniae. Frogs were collected from five locations throughout Costa Rica that are known to vary in their alkaloid profiles. Alkaloids were isolated from individual skins, and extracts were assayed against both pathogens. Microbe subcultures were inoculated with extracted alkaloids to create dose-response curves. Subsequent spectrophotometry and cell counting assays were used to assess growth inhibition. GC-MS was used to characterize and quantify alkaloids in frog extracts, and our results suggest that variation in alkaloid defenses lead to differences in inhibition of these pathogens. The present study provides the first evidence that alkaloid variation in a dendrobatid poison frog is associated with differences in inhibition of anuran pathogens, and offers further support that alkaloid defenses in poison frogs confer protection against both pathogens and predators.

  3. Production of Microbial Protease from Selected Soil Fungal Isolates ...

    African Journals Online (AJOL)

    Production of Microbial Protease from Selected Soil Fungal Isolates. ... Nigerian Journal of Biotechnology ... and 500C. The optimal pH on the enzyme production was observed to be between pH 3.5 and 5.5 for the organisms. Keywords: Soil microorganism, fungal isolate, incubation period, microbial enzyme. Nig J. Biotech.

  4. Pathogenic diversity of Sclerotium rolfsii isolates, a potential ...

    African Journals Online (AJOL)

    Administrator

    et al., 2002; Shukla and Pandey, 2007). Therefore, present investigation was carried out to study the pathogenic varia- bility and justify the separate identity of the S. rolfsii isolates associated with Parthenium. MATERIALS AND METHODS. Test isolates and their maintenance. Ten isolates of S. rolfsii incites collar rot disease ...

  5. The role of hyperparasitism in microbial pathogen ecology and evolution.

    Science.gov (United States)

    Parratt, Steven R; Laine, Anna-Liisa

    2016-08-01

    Many micro-organisms employ a parasitic lifestyle and, through their antagonistic interactions with host populations, have major impacts on human, agricultural and natural ecosystems. Most pathogens are likely to host parasites of their own, that is, hyperparasites, but how nested chains of parasites impact on disease dynamics is grossly neglected in the ecological and evolutionary literature. In this minireview we argue that the diversity and dynamics of micro-hyperparasites are an important component of natural host-pathogen systems. We use the current literature from a handful of key systems to show that observed patterns of pathogen virulence and disease dynamics may well be influenced by hyperparasites. Exploring these factors will shed light on many aspects of microbial ecology and disease biology, including resistance-virulence evolution, apparent competition, epidemiology and ecosystem stability. Considering the importance of hyperparasites in natural populations will have applied consequences for the field of biological control and therapeutic science, where hyperparastism is employed as a control mechanism but not necessarily ecologically understood.

  6. Molecular diagnostics for the detection and characterization of microbial pathogens.

    Science.gov (United States)

    Procop, Gary W

    2007-09-01

    New and advanced methods of molecular diagnostics are changing the way we practice clinical microbiology, which affects the practice of medicine. Signal amplification and real-time nucleic acid amplification technologies offer a sensitive and specific result with a more rapid turnaround time than has ever before been possible. Numerous methods of postamplification analysis afford the simultaneous detection and differentiation of numerous microbial pathogens, their mechanisms of resistance, and the construction of disease-specific assays. The technical feasibility of these assays has already been demonstrated. How these new, often more expensive tests will be incorporated into routine practice and the impact they will have on patient care remain to be determined. One of the most attractive uses for such techniques is to achieve a more rapid characterization of the infectious agent so that a narrower-spectrum antimicrobial agent may be used, which should have an impact on resistance patterns.

  7. Nucleic acid probes in the diagnosis of human microbial pathogens

    International Nuclear Information System (INIS)

    Hyypia, T.; Huovinen, P.; Holmberg, M.; Pettersson, U.

    1989-01-01

    The development of effective vaccines and antimicrobial drugs against infectious diseases has been among the most successful achievements in modern medicine. The control of these diseases requires efficient diagnostic methods for the evaluation of the prevalence of diseases and for initiation of specific treatment. Virtually all known microbes can be specifically identified today but in many cases further development is needed for more accurate, rapid, easy-to-use, and inexpensive diagnostic assays. Cell culture facilities are needed for the isolation of viruses in clinical specimens. Any gene of any known microorganism can be cloned in a vector and produced in large amounts economically and then used in diagnostic assays for the identification of the pathogen. The application of the nucleic acid hybridization methods in detection of human pathogens has received considerable attention during the past few years. This paper presents examples of this application of gene technology

  8. Pattern of microbial isolates and microbial sensitivity among HIV ...

    African Journals Online (AJOL)

    MJP

    2015-04-18

    Apr 18, 2015 ... asymptomatic patients with HIV infection in pregnancy. The isolated ..... sensitive to 72.7% of the drugs tested; also. E.coli which ... candida albicans. Schistosoma ... may be prone to abuse and subsequently the high level of ...

  9. Plastic potential: how the phenotypes and adaptations of pathogens are influenced by microbial interactions within plants.

    Science.gov (United States)

    O'Keeffe, Kayleigh R; Carbone, Ignazio; Jones, Corbin D; Mitchell, Charles E

    2017-08-01

    Predicting the effects of plant-associated microbes on emergence, spread, and evolution of plant pathogens demands an understanding of how pathogens respond to these microbes at two levels of biological organization: that of an individual pathogen and that of a pathogen population across multiple individual plants. We first examine the plastic responses of individual plant pathogens to microbes within a shared host, as seen through changes in pathogen growth and multiplication. We then explore the limited understanding of how within-plant microbial interactions affect pathogen populations and discuss the need to incorporate population-level observations with population genomic techniques. Finally, we suggest that integrating across levels will further our understanding of the ecological and evolutionary impacts of within-plant microbial interactions on pathogens. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Genomic Microbial Epidemiology Is Needed to Comprehend the Global Problem of Antibiotic Resistance and to Improve Pathogen Diagnosis.

    Science.gov (United States)

    Wyrsch, Ethan R; Roy Chowdhury, Piklu; Chapman, Toni A; Charles, Ian G; Hammond, Jeffrey M; Djordjevic, Steven P

    2016-01-01

    Contamination of waste effluent from hospitals and intensive food animal production with antimicrobial residues is an immense global problem. Antimicrobial residues exert selection pressures that influence the acquisition of antimicrobial resistance and virulence genes in diverse microbial populations. Despite these concerns there is only a limited understanding of how antimicrobial residues contribute to the global problem of antimicrobial resistance. Furthermore, rapid detection of emerging bacterial pathogens and strains with resistance to more than one antibiotic class remains a challenge. A comprehensive, sequence-based genomic epidemiological surveillance model that captures essential microbial metadata is needed, both to improve surveillance for antimicrobial resistance and to monitor pathogen evolution. Escherichia coli is an important pathogen causing both intestinal [intestinal pathogenic E. coli (IPEC)] and extraintestinal [extraintestinal pathogenic E. coli (ExPEC)] disease in humans and food animals. ExPEC are the most frequently isolated Gram negative pathogen affecting human health, linked to food production practices and are often resistant to multiple antibiotics. Cattle are a known reservoir of IPEC but they are not recognized as a source of ExPEC that impact human or animal health. In contrast, poultry are a recognized source of multiple antibiotic resistant ExPEC, while swine have received comparatively less attention in this regard. Here, we review what is known about ExPEC in swine and how pig production contributes to the problem of antibiotic resistance.

  11. [Isolation of endophytic fungi from medicinal plant Brucea javanica and their microbial inhibition activity].

    Science.gov (United States)

    Liang, Zi-Ning; Zhu, Hua; Lai, Kai-Ping; Chen, Long

    2014-04-01

    To isolate and identify endophytic fungi from Brucea javanica, and to detect the antimicrobial activity of these strains. Endophytic fungi were isolated by tissue inoculation culture and identified by conventional morphological characteristic method. Seven kinds of pathogenic fungi and three kinds of bacteria were used as targeting microbes to test microbial inhibition activities by agar plate antagonistic action and modified agar gel diffusion methods, respectively. A total of 83 endophytic fungi strains were isolated from the root, stem, leaf and fruit of Brucea javanica. 34 strains were obtained from the stem, 32 strains were obtained from the leaf, 15 strains were isolated from the root and 2 strains came from the fruit. These 73 strains which had been identified attribute to 5 orders, 6 families and 12 genera. For the isolated strains, 14 strains had antifungal activities against at least one pathogenic fungi, 9 strains showed antibacterial activities against one or more bacteria. Especially, the strain YJ-17 which belonged to Phomopsis genus showed the best inhibitory effect on the targeting microbes. The endophytic fungi from Brucea javanica show diversity and microbial inhibition activity, and are worthy for further study on plant disease controlling.

  12. 77 FR 45350 - Notice of Availability of Microbial Risk Assessment Guideline: Pathogenic Microorganisms With...

    Science.gov (United States)

    2012-07-31

    ... ENVIRONMENTAL PROTECTION AGENCY Notice of Availability of Microbial Risk Assessment Guideline: Pathogenic Microorganisms With Focus on Food and Water AGENCY: Environmental Protection Agency (EPA). ACTION... risk assessment and also promote consistency in approaches and methods. The MRA Guideline can be...

  13. COMPARATIVE EVALUATION OF CULTURE MEDIA FOR PATHOGEN ISOLATION OF PURULENT BACTERIAL MENINGITIS

    Directory of Open Access Journals (Sweden)

    Ya. V. Podkopaev

    2016-01-01

    Full Text Available The State Research Center for Applied Microbiology and Biotechnology has designed two nutrient media — chocolate agar and PBM-agar to isolate pathogens of purulent bacterial meningitis (PBM. In our previous research using collected microbial strains the media were shown to be highly susceptible and to provide the growth of Neisseria meningiti-dis, Streptococcus pneumoniae and Haemophilus influenzae strains, when inoculated with microbial suspensions containing single cells. When isolating Haemophilus influenzae, meningococci, and pneumococci the use of selective additives in both media assures selective isolation of required microorganisms, inhibiting contaminants. The objective of this research was to assess the media in bacteriological tests of clinical samples collected from the upper and lower respiratory tract in humans. The bacteriological plating of throat smear specimens (n = 90 from children and adults at the age of 0 to 66 with disorder of the upper respiratory tract on chocolate agar, PBM-agar and on a control medium in the absence of selective additives resulted in the equal amount of microbial cultures isolated. Of 154 isolated cultures 2, 23 and 9 were attributed to Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae, respectively. The plating of throat smears (n = 10 from healthy people at the age of 30 to 55 on the analyzable and control media in the presence of additives allowed us to selectively isolate Haemophilus influenzae and Streptococcus pneumoniae cultures without a quantitative loss, with contaminants inhibited. By their growth characteristics chocolate agar and PBM-agar were highly competitive with reference media being used in clinical practice for isolating main causative agents of purulent bacterial meningitis.

  14. Medicinal Plants Based Products Tested on Pathogens Isolated from Mastitis Milk

    Directory of Open Access Journals (Sweden)

    Claudia Pașca

    2017-09-01

    Full Text Available Bovine mastitis a major disease that is commonly associated with bacterial infection. The common treatment is with antibiotics administered intramammary into infected quarters of the udder. The excessive use of antibiotics leads to multidrug resistance and associated risks for human health. In this context, the search for alternative drugs based on plants has become a priority in livestock medicine. These products have a low manufacturing cost and no reports of antimicrobial resistance to these have been documented. In this context, the main objective of this study was to determine the antimicrobial effect of extracts and products of several indigenous, or acclimatized plants on pathogens isolated from bovine mastitis. A total of eleven plant alcoholic extracts and eight plant-derived products were tested against 32 microorganisms isolated from milk. The obtained results have shown an inhibition of bacterial growth for all tested plants, with better results for Evernia prunastri, Artemisia absinthium, and Lavandula angustifolia. Moreover, E. prunastri, Populus nigra, and L. angustifolia presented small averages of minimum inhibitory and bactericidal concentrations. Among the plant-derived products, three out of eight have shown a strong anti-microbial effect comparable with the effect of florfenicol and enrofloxacin, and better than individual plant extracts possibly due to synergism. These results suggest an important anti-microbial effect of these products on pathogens isolated from bovine mastitis with a possible applicability in this disease.

  15. Pathogenicity of Human ST23 Streptococcus agalactiae to Fish and Genomic Comparison of Pathogenic and Non-pathogenic Isolates

    Directory of Open Access Journals (Sweden)

    Rui Wang

    2017-10-01

    Full Text Available Streptococcus agalactiae, or Group B Streptococcus (GBS, is a major pathogen causing neonatal sepsis and meningitis, bovine mastitis, and fish meningoencephalitis. CC23, including its namesake ST23, is not only the predominant GBS strain derived from human and cattle, but also can infect a variety of homeothermic and poikilothermic species. However, it has never been characterized in fish. This study aimed to determine the pathogenicity of ST23 GBS to fish and explore the mechanisms causing the difference in the pathogenicity of ST23 GBS based on the genome analysis. Infection of tilapia with 10 human-derived ST23 GBS isolates caused tissue damage and the distribution of pathogens within tissues. The mortality rate of infection was ranged from 76 to 100%, and it was shown that the mortality rate caused by only three human isolates had statistically significant difference compared with fish-derived ST7 strain (P < 0.05, whereas the mortality caused by other seven human isolates did not show significant difference compared with fish-derived ST7 strain. The genome comparison and prophage analysis showed that the major genome difference between virulent and non-virulent ST23 GBS was attributed to the different prophage sequences. The prophage in the P1 region contained about 43% GC and encoded 28–39 proteins, which can mediate the acquisition of YafQ/DinJ structure for GBS by phage recombination. YafQ/DinJ belongs to one of the bacterial toxin–antitoxin (TA systems and allows cells to cope with stress. The ST23 GBS strains carrying this prophage were not pathogenic to tilapia, but the strains without the prophage or carrying the pophage that had gene mutation or deletion, especially the deletion of YafQ/DinJ structure, were highly pathogenic to tilapia. In conclusion, human ST23 GBS is highly pathogenic to fish, which may be related to the phage recombination.

  16. Volatile-mediated suppression of plant pathogens is related to soil properties and microbial community composition

    NARCIS (Netherlands)

    Van Agtmaal, M.; Straathof, A.L.; Termorshuizen, Aad J; Lievens, Bart; Hoffland, Ellis; De Boer, W.

    2018-01-01

    There is increasing evidence that the soil microbial community produces a suite of volatile organic compounds that suppress plant pathogens. However, it remains unknown which soil properties and management practices influence volatile-mediated pathogen suppression. The aim of this study was to

  17. Volatile-mediated suppression of plant pathogens is related to soil properties and microbial community composition

    NARCIS (Netherlands)

    Agtmaal, van Maaike; Straathof, Angela L.; Termorshuizen, Aad; Lievens, Bart; Hoffland, Ellis; Boer, de Wietse

    2018-01-01

    There is increasing evidence that the soil microbial community produces a suite of volatile organic compounds that suppress plant pathogens. However, it remains unknown which soil properties and management practices influence volatile-mediated pathogen suppression. The aim of this study was to

  18. Machine learning for the meta-analyses of microbial pathogens' volatile signatures.

    Science.gov (United States)

    Palma, Susana I C J; Traguedo, Ana P; Porteira, Ana R; Frias, Maria J; Gamboa, Hugo; Roque, Ana C A

    2018-02-20

    Non-invasive and fast diagnostic tools based on volatolomics hold great promise in the control of infectious diseases. However, the tools to identify microbial volatile organic compounds (VOCs) discriminating between human pathogens are still missing. Artificial intelligence is increasingly recognised as an essential tool in health sciences. Machine learning algorithms based in support vector machines and features selection tools were here applied to find sets of microbial VOCs with pathogen-discrimination power. Studies reporting VOCs emitted by human microbial pathogens published between 1977 and 2016 were used as source data. A set of 18 VOCs is sufficient to predict the identity of 11 microbial pathogens with high accuracy (77%), and precision (62-100%). There is one set of VOCs associated with each of the 11 pathogens which can predict the presence of that pathogen in a sample with high accuracy and precision (86-90%). The implemented pathogen classification methodology supports future database updates to include new pathogen-VOC data, which will enrich the classifiers. The sets of VOCs identified potentiate the improvement of the selectivity of non-invasive infection diagnostics using artificial olfaction devices.

  19. Microbial transformation of (-)-isolongifolol by plant pathogenic fungus Glomerella cingulata.

    Science.gov (United States)

    Miyazawa, Mitsuo; Sakata, Kazuki; Ueda, Masashi

    2010-01-01

    The biotransformation of terpenoids using the plant pathogenic fungus as a biocatalyst to produce useful novel organic compounds was investigated. The biotransformation of sesquiterpen alcohol, (-)-isolongifolol (1) was investigated using plant pathogenic fungus Glomerella cingulata as a biocatalyst. Compound 1 was converted to (-)-(3R)-3-hydroxy-isolongifolol and (-)-(9R)-9-hydroxy-isolongifolol by G. cingulata.

  20. IPM potentials of microbial pathogens and diseases of mites

    NARCIS (Netherlands)

    van der Geest, L.P.S.; Ciancio, A.; Mukerji, K.G.

    2010-01-01

    An overview is given of diseases in mites, caused by infectious microorganisms. Many pathogens play an important role in the regulation of natural populations of mite populations and are for this reason subject of research on the feasibility to develop such pathogens to biological control agents.

  1. Pathogenic microbial ancient DNA: a problem or an opportunity?

    DEFF Research Database (Denmark)

    Willerslev, Eske; Cooper, Alan

    2006-01-01

    cloning. Yet these studies have used mobile insertion elements (e.g. IS 6110 in tuberculosis) or conserved loci (e.g. 16S) to detect the presence of pathogens, and very similar or identical sequences have been reported from environmental bacteria (Gilbert et al. 2004). For example, Rollo & Marota (1999......We agree with Donoghue & Spigelman (2005) that, although pathogen studies hold great potential, any discussion requires a critical assessment of the results to date. However, we did note, as did Pääbo et al. (2004), that the field of ancient pathogen DNA still lacks a series of well......-controlled and rigorous studies that address technical issues and reliability criteria. This is unfortunate, as the rapid evolutionary rate of many pathogens offers a unique means to establish the authenticity of ancient pathogen sequences-since they should clearly be ancestral to modern genetic diversity (e.g. Reid et...

  2. Efficacy of medicinal essential oils against pathogenic Malassezia sp. isolates.

    Science.gov (United States)

    Khosravi, A R; Shokri, H; Fahimirad, S

    2016-03-01

    The purposes of this study were to evaluate the distribution pattern and population size of Malassezia species in dogs with atopic dermatitis (AD) and the inhibitory efficacy of Zataria multiflora, Thymus kotschyanus, Mentha spicata, Artemisia sieberi, Rosmarinus officinalis and Heracleum persicum essential oils against pathogenic Malassezia isolates. The samples were collected from 5 different anatomical sites of 33 atopic dogs and cultured onto modified Dixon agar (MDA) and Sabouraud dextrose agar (SDA) media. The essential oil extraction was performed by steam distillation using Clevenger system. Anti-Malassezia efficacy of medicinal essential oils and standard drugs was evaluated using broth microdilution method. A total of 103 yeast colonies were isolated from dogs with AD. Eight different Malassezia species were identified as follows: Malassezia pachydermatis (81.4%), M. globosa (7.8%), M. restricta (3.9%), M. sloofiae (2.9%), M. furfur (1%), M. nana (1%), M. obtusa (1%) and M. sympodialis (1%). The most and least infected sites were: anal (21.2%) and ear (10.6%) respectively. M. pachydermatis was the most frequent Malassezia species isolated from both skin and mucosa of dogs with AD. Antifungal susceptibility test revealed the inhibitory efficacy of essential oils on pathogenic Malassezia isolates with minimum inhibitory concentration (MIC(90)) values ranging from 30 to 850 μg/mL. Among the tested oils, Z. multiflora and T. kotschyanus exhibited the highest inhibitory effects (Pessential oils of Z. multiflora and T. kotschyanus showed strong antifungal activity against pathogenic Malassezia species tested. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  3. Overcoming antibiotic resistance: Is siderophore Trojan horse conjugation an answer to evolving resistance in microbial pathogens?

    Science.gov (United States)

    Dhusia, Kalyani; Bajpai, Archana; Ramteke, P W

    2018-01-10

    Comparative study of siderophore biosynthesis pathway in pathogens provides potential targets for antibiotics and host drug delivery as a part of computationally feasible microbial therapy. Iron acquisition using siderophore models is an essential and well established model in all microorganisms and microbial infections a known to cause great havoc to both plant and animal. Rapid development of antibiotic resistance in bacterial as well as fungal pathogens has drawn us at a verge where one has to get rid of the traditional way of obstructing pathogen using single or multiple antibiotic/chemical inhibitors or drugs. 'Trojan horse' strategy is an answer to this imperative call where antibiotic are by far sneaked into the pathogenic cell via the siderophore receptors at cell and outer membrane. This antibiotic once gets inside, generates a 'black hole' scenario within the opportunistic pathogens via iron scarcity. For pathogens whose siderophore are not compatible to smuggle drug due to their complex conformation and stiff valence bonds, there is another approach. By means of the siderophore biosynthesis pathways, potential targets for inhibition of these siderophores in pathogenic bacteria could be achieved and thus control pathogenic virulence. Method to design artificial exogenous siderophores for pathogens that would compete and succeed the battle of intake is also covered with this review. These manipulated siderophore would enter pathogenic cell like any other siderophore but will not disperse iron due to which iron inadequacy and hence pathogens control be accomplished. The aim of this review is to offer strategies to overcome the microbial infections/pathogens using siderophore. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Assessing the Consequences of Microbial Infection in Field Trials: Seen, Unseen, Beneficial, Parasitic and Pathogenic

    Directory of Open Access Journals (Sweden)

    Mark E. Looseley

    2014-06-01

    Full Text Available Microbial infections of crop plants present an ongoing threat to agricultural production. However, in recent years, we have developed a more nuanced understanding of the ecological role of microbes and how they interact with plants. This includes an appreciation of the influence of crop physiology and environmental conditions on the expression of disease symptoms, the importance of non-pathogenic microbes on host plants and pathogens, and the capacity for plants to act as hosts for human pathogens. Alongside this we now have a variety of tools available for the identification and quantification of microbial infections on crops grown under field conditions. This review summarises some of the consequences of microbial infections in crop plants, and discusses how new and established assessment tools can be used to understand these processes. It challenges our current assumptions in yield loss relationships and offers understanding of the potential for more resilient crops.

  5. Pathogen self defense: mechanisms to counteract microbial antagonism

    NARCIS (Netherlands)

    Duffy, B.K.; Schouten, A.; Raaijmakers, J.M.

    2003-01-01

    Natural and agricultural ecosystems harbor a wide variety of microorganisms that play an integral role in plant health, crop productivity, and preservation of multiple ecosystem functions. Interactions within and among microbial communities are numerous and range from synergistic and mutualistic to

  6. Disease induction by human microbial pathogens in plant-model systems: potential, problems and prospects.

    Science.gov (United States)

    van Baarlen, Peter; van Belkum, Alex; Thomma, Bart P H J

    2007-02-01

    Relatively simple eukaryotic model organisms such as the genetic model weed plant Arabidopsis thaliana possess an innate immune system that shares important similarities with its mammalian counterpart. In fact, some human pathogens infect Arabidopsis and cause overt disease with human symptomology. In such cases, decisive elements of the plant's immune system are likely to be targeted by the same microbial factors that are necessary for causing disease in humans. These similarities can be exploited to identify elementary microbial pathogenicity factors and their corresponding targets in a green host. This circumvents important cost aspects that often frustrate studies in humans or animal models and, in addition, results in facile ethical clearance.

  7. A low pathogenic H5N2 influenza virus isolated in Taiwan acquired high pathogenicity by consecutive passages in chickens.

    OpenAIRE

    Soda, Kosuke; Cheng, Ming-Chu; Yoshida, Hiromi; Endo, Mayumi; Lee, Shu-Hwae; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Wang, Ching-Ho; Kida, Hiroshi

    2011-01-01

    H5N2 viruses were isolated from cloacal swab samples of apparently healthy chickens in Taiwan in 2003 and 2008 during surveillance of avian influenza. Each of the viruses was eradicated by stamping out. The official diagnosis report indicated that the Intravenous Pathogenicity Indexes (IVPIs) of the isolates were 0.00 and 0.89, respectively, indicating that these were low pathogenic strains, although the hemagglutinin of the strain isolated in 2008 (Taiwan08) had multibasic amino acid residue...

  8. Microbial Flora and Food Borne Pathogens on Minced Meat and ...

    African Journals Online (AJOL)

    BACKGROUND: Food-borne pathogens are the leading cause of illness and death in developing countries. Changes in eating habits, mass catering, unsafe food storage conditions and poor hygiene practices are major contributing factors to food associated illnesses. In Ethiopia, the widespread habit of raw beef ...

  9. CONDUCTING-POLYMER NANOWIRE IMMUNOSENSOR ARRAYS FOR MICROBIAL PATHOGENS

    Science.gov (United States)

    The lack of methods for routine rapid and sensitive detection and quantification of specific pathogens has limited the amount of information available on their occurrence in drinking water and other environmental samples. The nanowire biosensor arrays developed in this study w...

  10. Biological activity of the non-microbial fraction of kefir: antagonism against intestinal pathogens.

    Science.gov (United States)

    Iraporda, Carolina; Abatemarco Júnior, Mário; Neumann, Elisabeth; Nunes, Álvaro Cantini; Nicoli, Jacques R; Abraham, Analía G; Garrote, Graciela L

    2017-08-01

    Kefir is a fermented milk obtained by the activity of kefir grains which are composed of lactic and acetic acid bacteria, and yeasts. Many beneficial health effects have been associated with kefir consumption such as stimulation of the immune system and inhibition of pathogenic microorganisms. The biological activity of kefir may be attributed to the presence of a complex microbiota as well as the microbial metabolites that are released during fermentation. The aim of this work was to characterise the non-microbial fraction of kefir and to study its antagonism against Escherichia coli, Salmonella spp. and Bacillus cereus. During milk fermentation there was a production of organic acids, mainly lactic and acetic acid, with a consequent decrease in pH and lactose content. The non-microbial fraction of kefir added to nutrient broth at concentrations above 75% v/v induced a complete inhibition of pathogenic growth that could be ascribed to the presence of un-dissociated lactic acid. In vitro assays using an intestinal epithelial cell model indicated that pre-incubation of cells with the non-microbial fraction of kefir did not modify the association/invasion of Salmonella whereas pre-incubation of Salmonella with this fraction under conditions that did not affect their viability significantly decreased the pathogen's ability to invade epithelial cells. Lactate exerted a protective effect against Salmonella in a mouse model, demonstrating the relevance of metabolites present in the non-microbial fraction of kefir produced during milk fermentation.

  11. Global Warming and Trans-Boundary Movement of Waterborne Microbial Pathogens - Book Chapter

    Science.gov (United States)

    Subtle increases in temperature can have profound impacts on the prevalence of various waterborne microbial pathogens. Such impacts may be seen in three major areas, 1) fecally contaminated drinking water, 2) fresh produce that has been irrigated or processed with contaminated wa...

  12. Microbial diversity and putative opportunistic pathogens in dishwasher biofilm communities

    DEFF Research Database (Denmark)

    Raghupathi, Prem Krishnan; Zupančič, Jerneja; Brejnrod, Asker Daniel

    2018-01-01

    impact the abundance of microbial groups, and investigated on the inter- and intra-kingdom interactions that shape these biofilms. The age, the usage frequency and hardness of incoming tap water of dishwashers had significant impact on bacterial and fungal composition. Representatives ofCandidaspp. were...... and interactions were vital in the process of biofilm formation, where mixed complexes of the two, bacteria and fungi, could provide a preliminary biogenic structure for the establishment of these biofilms.IMPORTANCEWorldwide demand for household appliances, such as dishwashers and washing machines, is increasing...

  13. Antimicrobial profiles of periodontal pathogens isolated from periodontitis patients in the Netherlands and Spain

    NARCIS (Netherlands)

    van Winkelhoff, AJ; Herrera, D; Oteo, A; Sanz, M

    Background and Aim: Antimicrobial resistance of periodontal pathogens towards currently used antibiotics in periodontics has been investigated in a previous study. Microbial resistance in the periodontal microflora was more frequently observed in Spanish patients in comparison with Dutch patients.

  14. Development of biocontrol agents from food microbial isolates for controlling post-harvest peach brown rot caused by Monilinia fructicola.

    Science.gov (United States)

    Zhou, Ting; Schneider, Karin E; Li, Xiu-Zhen

    2008-08-15

    An unconventional strategy of screening food microbes for biocontrol activity was used to develop biocontrol agents for controlling post-harvest peach brown rot caused by Monilinia fructicola. Forty-four microbial isolates were first screened for their biocontrol activity on apple fruit. Compared with the pathogen-only check, seven of the 44 isolates reduced brown rot incidence by >50%, including four bacteria: Bacillus sp. C06, Lactobacillus sp. C03-b and Bacillus sp. T03-c, Lactobacillus sp. P02 and three yeasts: Saccharomyces delbrueckii A50, S. cerevisiae YE-5 and S. cerevisiae A41. Eight microbial isolates were selected for testing on peaches by wound co-inoculation with mixtures of individual microbial cultures and conidial suspension of M. fructicola. Only two of them showed significant biocontrol activity after five days of incubation at 22 degrees C. Bacillus sp. C06 suppressed brown rot incidence by 92% and reduced lesion diameter by 88% compared to the pathogen-only check. Bacillus sp.T03-c reduced incidence and lesion diameter by 40% and 62%, respectively. The two isolates were compared with Pseudomonas syringae MA-4, a biocontrol agent for post-harvest peach diseases, by immersing peaches in an aliquot containing individual microbial isolates and the pathogen conidia. Treatments with isolates MA-4, C06 and T03-c significantly controlled brown rot by 91, 100, and 100% respectively. However, only isolates MA-4 and C06 significantly reduced brown rot by 80% and 15%, respectively when bacterial cells alone were applied. On naturally infected peaches, both the bacterial culture and its cell-free filtrate of the isolate C06 significantly controlled peach decay resulting in 77 and 90% reduction, respectively, whereas the treatment using only the bacterial cells generally had no effect. Isolate C06 is a single colony isolate obtained from a mesophilic cheese starter, and has been identified belonging to Bacillus amyloliquefaciens. The results have clearly

  15. Antimicrobial-Resistance Genetic Markers in Potentially Pathogenic Gram Positive Cocci Isolated from Brazilian Soft Cheese.

    Science.gov (United States)

    Resende, Juliana Alves; Fontes, Cláudia Oliveira; Ferreira-Machado, Alessandra Barbosa; Nascimento, Thiago César; Silva, Vânia Lúcia; Diniz, Cláudio Galuppo

    2018-02-01

    Although most Brazilian dairy products meet high technological standards, there are quality issues regarding milk production, which may reduce the final product quality. Several microbial species may contaminate milk during manufacture and handling. If antimicrobial usage remains uncontrolled in dairy cattle, the horizontal transfer of antimicrobial resistance genes in foodstuffs may be of particular concern for both food producers and dairy industry. This study focused on the evaluation of putative Gram positive cocci in Minas cheese and of antimicrobial and biocide resistance genes among the isolated bacteria. Representative samples of 7 different industrially trademarked Minas cheeses (n = 35) were processed for selective culture and isolation of Gram positive cocci. All isolated bacteria were identified by DNA sequencing of the 16S rRNA gene. Antimicrobial resistance genes were screened by PCR. Overall, 208 strains were isolated and identified as follows: Enterococcus faecalis (47.6%), Macrococcus caseolyticus (18.3%), Enterococcus faecium (11.5%), Enterococcus caseliflavus (7.7%), Staphylococcus haemolyticus (7.2%), Staphylococcus aureus (4.3%), Staphylococcus epidermidis (2.9%), and Enterococcus hirae (0.5%). The genetic markers mecA (78.0%) and smr (71.4%) were the most prevalent, but others were also detected, such as blaZ (65.2%), msrA (60.9%), msrB (46.6%), linA (54.7%), and aacA-aphD (47.6%). The occurrence of opportunist pathogenic bacteria harboring antimicrobial resistance markers in the cheese samples are of special concern, since these bacteria are not considered harmful contaminating agents according to the Brazilian sanitary regulations. However, they are potentially pathogenic bacteria and the cheese may be considered a reservoir for antimicrobial resistance genes available for horizontal transfer through the food chain, manufacturing personnel and consumers. © 2018 Institute of Food Technologists®.

  16. Identification and Pathogenic Potential of Clinical Bacillus and Paenibacillus Isolates.

    Directory of Open Access Journals (Sweden)

    Francesco Celandroni

    Full Text Available The soil-related Bacillus and Paenibacillus species have increasingly been implicated in various human diseases. Nevertheless, their identification still poses problems in the clinical microbiology laboratory and, with the exception of Bacillus anthracis and Bacillus cereus, little is known on their pathogenicity for humans. In this study, we evaluated the use of matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS in the identification of clinical isolates of these genera and conducted genotypic and phenotypic analyses to highlight specific virulence properties. Seventy-five clinical isolates were subjected to biochemical and MALDI-TOF MS identification. 16S rDNA sequencing and supplemental tests were used to solve any discrepancies or failures in the identification results. MALDI-TOF MS significantly outperformed classical biochemical testing for correct species identification and no misidentification was obtained. One third of the collected strains belonged to the B. cereus species, but also Bacillus pumilus and Bacillus subtilis were isolated at high rate. Antimicrobial susceptibility testing showed that all the B. cereus, B. licheniformis, B. simplex, B. mycoides, Paenibacillus glucanolyticus and Paenibacillus lautus isolates are resistant to penicillin. The evaluation of toxin/enzyme secretion, toxin-encoding genes, motility, and biofilm formation revealed that B. cereus displays the highest virulence potential. However, although generally considered nonpathogenic, most of the other species were shown to swim, swarm, produce biofilms, and secrete proteases that can have a role in bacterial virulence. In conclusion, MALDI-TOF MS appears useful for fast and accurate identification of Bacillus and Paenibacillus strains whose virulence properties make them of increasing clinical relevance.

  17. Microbial Community Composition Impacts Pathogen Iron Availability during Polymicrobial Infection.

    Directory of Open Access Journals (Sweden)

    Apollo Stacy

    2016-12-01

    Full Text Available Iron is an essential nutrient for bacterial pathogenesis, but in the host, iron is tightly sequestered, limiting its availability for bacterial growth. Although this is an important arm of host immunity, most studies examine how bacteria respond to iron restriction in laboratory rather than host settings, where the microbiome can potentially alter pathogen strategies for acquiring iron. One of the most important transcriptional regulators controlling bacterial iron homeostasis is Fur. Here we used a combination of RNA-seq and chromatin immunoprecipitation (ChIP-seq to characterize the iron-restricted and Fur regulons of the biofilm-forming opportunistic pathogen Aggregatibacter actinomycetemcomitans. We discovered that iron restriction and Fur regulate 4% and 3.5% of the genome, respectively. While most genes in these regulons were related to iron uptake and metabolism, we found that Fur also directly regulates the biofilm-dispersing enzyme Dispersin B, allowing A. actinomycetemcomitans to escape from iron-scarce environments. We then leveraged these datasets to assess the availability of iron to A. actinomycetemcomitans in its primary infection sites, abscesses and the oral cavity. We found that A. actinomycetemcomitans is not restricted for iron in a murine abscess mono-infection, but becomes restricted for iron upon co-infection with the oral commensal Streptococcus gordonii. Furthermore, in the transition from health to disease in human gum infection, A. actinomycetemcomitans also becomes restricted for iron. These results suggest that host iron availability is heterogeneous and dependent on the infecting bacterial community.

  18. Microbial diversity and prevalence of foodborne pathogens in cheap and junk foods consumed by primary schoolchildren.

    Science.gov (United States)

    Kim, M J; Kim, S A; Kang, Y S; Hwang, I G; Rhee, M S

    2013-07-01

    Aerobic plate counts (APC), coliforms, Bacillus cereus, Escherichia coli and eight foodborne pathogens were tested in 1008 cheap and junk foods, including candies, dried cakes, chewing gum, chocolate, dried and seasoned seafood, ice cream, and sugary foods. APCs were positive for 342 samples (33·9%), and the majority of the counts were 2-3 log CFU g(-1) or ml(-1) (average: 1·10 log CFU g(-1) or ml(-1) ). Most samples (97·3%) contained no coliforms (average: 0·07 log CFU g(-1) or ml(-1) ). Bacillus cereus was detected in 68 samples (average: 0·14 log CFU g(-1) or ml(-1) ). Escherichia coli and Listeria monocytogenes were detected in 6 and 1 samples, respectively, whereas other foodborne pathogens were not isolated. The highest bacterial counts were associated with dried and seasoned seafood products and dried cakes, suggesting that appropriate regulations of these food types should be considered. Cheap and junk foods were produced mainly in developing countries, but there were no significant differences in the bacterial counts among different countries of origin. The presence of foodborne pathogens may pose a risk for children. These results suggest that there is cause for deeper concern about the safety of these foods and that effective countermeasures should be established to improve their microbiological safety. Food safety is especially important for children, but only limited information is available about the microbiological quality of cheap and junk foods that are consumed frequently by primary schoolchildren (e.g. dried cakes, candies and chocolates). The present study investigated the microbial quality of cheap and junk foods, and our results indicate that these foods are a potential health risk for children, therefore, deeper concern about the safety of these foods and effective countermeasures should be established to improve their microbiological safety. The present study may contribute to the development of an appropriate child food

  19. Appraisal of Microbial Evolution to Commensalism and Pathogenicity in Humans

    Directory of Open Access Journals (Sweden)

    Asit Ranjan Ghosh

    2013-01-01

    Full Text Available The human body is host to a number of microbes occurring in various forms of host-microbe associations, such as commensals, mutualists, pathogens and opportunistic symbionts. While this association with microbes in certain cases is beneficial to the host, in many other cases it seems to offer no evident benefit or motive. The emergence and re-emergence of newer varieties of infectious diseases with causative agents being strains that were once living in the human system makes it necessary to study the environment and the dynamics under which this host microbe relationship thrives. The present discussion examines this interaction while tracing the origins of this association, and attempts to hypothesize a possible framework of selective pressures that could have lead microbes to inhabit mammalian host systems.

  20. Model-Based Analysis of the Potential of Macroinvertebrates as Indicators for Microbial Pathogens in Rivers

    Directory of Open Access Journals (Sweden)

    Rubén Jerves-Cobo

    2018-03-01

    Full Text Available The quality of water prior to its use for drinking, farming or recreational purposes must comply with several physicochemical and microbiological standards to safeguard society and the environment. In order to satisfy these standards, expensive analyses and highly trained personnel in laboratories are required. Whereas macroinvertebrates have been used as ecological indicators to review the health of aquatic ecosystems. In this research, the relationship between microbial pathogens and macrobenthic invertebrate taxa was examined in the Machangara River located in the southern Andes of Ecuador, in which 33 sites, according to their land use, were chosen to collect physicochemical, microbiological and biological parameters. Decision tree models (DTMs were used to generate rules that link the presence and abundance of some benthic families to microbial pathogen standards. The aforementioned DTMs provide an indirect, approximate, and quick way of checking the fulfillment of Ecuadorian regulations for water use related to microbial pathogens. The models built and optimized with the WEKA package, were evaluated based on both statistical and ecological criteria to make them as clear and simple as possible. As a result, two different and reliable models were obtained, which could be used as proxy indicators in a preliminary assessment of pollution of microbial pathogens in rivers. The DTMs can be easily applied by staff with minimal training in the identification of the sensitive taxa selected by the models. The presence of selected macroinvertebrate taxa in conjunction with the decision trees can be used as a screening tool to evaluate sites that require additional follow up analyses to confirm whether microbial water quality standards are met.

  1. Isolation of pathogenic Escherichia coli from buffalo meat sold in Parbhani city, Maharashtra, India

    Directory of Open Access Journals (Sweden)

    M. S. Vaidya

    2013-10-01

    Full Text Available Aim: Isolation, characterization, in-vitro pathogenicity and antibiogram study of E.coli from buffalo meat sold in Parbhani city. Materials and Methods: Meat samples were collected from buffalo immediately after slaughter. Isolation, identification and enumeration of E. coli were done by following standard methods and protocols. Hemolysin test and Congo red binding assay were used to study in-vitro pathogenicity of E. coli isolates. Disc diffusion method was used to study antibiogram of pathogenic E. coli isolates. Results: A total of 250 buffalo meat samples were collected and processed. A total of 22 (8.80 percent E. coli isolates were isolated with average differential count of 1.231 ± 0.136 log cfu/g on EMB agar. All the E. coli isolates were confirmed by 10 Grams staining, biochemical reactions and sugar fermentation and motility tests. A total of 9 (3.6 percent E. coli isolates were found to be pathogenic by in-vitro pathogenicity testing. Antibiogram studies of pathogenic E. coli isolates showed that all 9 isolates were sensitive to gentamycin (20 ± 1.49 mm while 7 isolate showed resistance to enrofloxacin (18.22 ± 3.58 mm and tetracycline (11.44 ± 2.04 mm. Conclusion: Buffalo meat sold in Parbhani city is an important source of E. coli infection to human population. A total of 9 pathogenic E. coli were isolated from buffalo meat immediately after slaughter. All isolates were characterized and confirmed pathogenic by in-vitro pathogenicity tests. Antibiogram studies of all isolates revealed sensitivity to gentamicin and resistance to tetracycline and enrofloxacin. [Vet World 2013; 6(5.000: 277-279

  2. Pathogenicity of Metarrhizium anisopliae (Metsch.) Sorokin and Beauveria bassiana (Bals.) Vuillemin isolates to Scaptocoris carvalhoi Becker (Hemiptera, Cydnidae)

    International Nuclear Information System (INIS)

    Xavier, Luciane Modenez Saldivar; Avila, Crebio Jose

    2006-01-01

    Pathogenicity of the fungi Metarrhizium anisopliae (Metsch.) Sorokin and Beauveria bassiana (Bals.) Vuillemin to stink bug Scaptocoris carvalhoi Becker, 1967 was evaluated under laboratory and greenhouse conditions. Experiments were carried out at EMBRAPA Agropecuaria Oeste, Dourados, Mato Grosso do Sul State, Brazil, in 2003. Ten M. anisopliae and eleven B. bassiana isolates were evaluated in laboratory using a completely randomized experimental design with five replicates (10 adults and 5 nymphs/plot). The pathogenicity of M. anisopliae isolate (Ma69) was also separately evaluated against nymphs and adults in laboratory and greenhouse. The stink bug mortality levels were higher for M. anisopliae isolates (between 73.3% and 94.7% than for B. bassiana isolates (between 10.7% and 78.7%). In greenhouse, stink bug mortality due to the M. anisopliae isolate (Ma69) was 57.3%, and there was no difference of mortality for nymphs and adults of stink bug in laboratory. However, in greenhouse, mortality levels were significantly higher (p<0,05) for nymphs (38,4%) than for adults (16,2%). From these data, we conclude that M. anisopliae isolate Ma69 was efficient to control S. carvalhoi in laboratory and in greenhouse, thus being a promising choice for use as a microbial insecticide under field conditions. (author)

  3. Distinct Trajectories of Massive Recent Gene Gains and Losses in Populations of a Microbial Eukaryotic Pathogen.

    Science.gov (United States)

    Hartmann, Fanny E; Croll, Daniel

    2017-11-01

    Differences in gene content are a significant source of variability within species and have an impact on phenotypic traits. However, little is known about the mechanisms responsible for the most recent gene gains and losses. We screened the genomes of 123 worldwide isolates of the major pathogen of wheat Zymoseptoria tritici for robust evidence of gene copy number variation. Based on orthology relationships in three closely related fungi, we identified 599 gene gains and 1,024 gene losses that have not yet reached fixation within the focal species. Our analyses of gene gains and losses segregating in populations showed that gene copy number variation arose preferentially in subtelomeres and in proximity to transposable elements. Recently lost genes were enriched in virulence factors and secondary metabolite gene clusters. In contrast, recently gained genes encoded mostly secreted protein lacking a conserved domain. We analyzed the frequency spectrum at loci segregating a gene presence-absence polymorphism in four worldwide populations. Recent gene losses showed a significant excess in low-frequency variants compared with genome-wide single nucleotide polymorphism, which is indicative of strong negative selection against gene losses. Recent gene gains were either under weak negative selection or neutral. We found evidence for strong divergent selection among populations at individual loci segregating a gene presence-absence polymorphism. Hence, gene gains and losses likely contributed to local adaptation. Our study shows that microbial eukaryotes harbor extensive copy number variation within populations and that functional differences among recently gained and lost genes led to distinct evolutionary trajectories. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  4. Isolation of antibiotic-resistant pathogenic and potentially ...

    African Journals Online (AJOL)

    2010-09-13

    Sep 13, 2010 ... The aim of the present study is to determine the pathogenic and potentially ... Keywords: pathogenic bacteria; antibiotic resistance; carpets; mosques; Tripoli; Libya .... During the process of praying, a Muslim is obliged to go.

  5. Current knowledge on groundwater microbial pathogens and their control

    Science.gov (United States)

    Macler, Bruce A.; Merkle, Jon C.

    Those who drink groundwater that has not been disinfected are at increased risk of infection and disease from pathogenic microorganisms. Recent studies have shown that up to half of all US drinking-water wells tested had evidence of fecal contamination. A significant fraction of all waterborne disease outbreaks is associated with groundwater. An estimated 750,000 to 5.9million illnesses per year result from contaminated groundwaters in the US. Mortality from these illnesses may be 1400-9400 deaths per year. Control of these pathogens starts with source-water protection activities to prevent fecal contamination of aquifers and wells. These include assessment of wellhead vulnerability to fecal contamination and correction of identified deficiencies. Correction may include control of sources or rehabilitation of the well itself. Disinfection can serve as a useful barrier and is recommended as a prudent public-health policy for all groundwater systems. Ceux qui boivent une eau souterraine non désinfectée présentent un risque accru d'infection et de maladie par des germes pathogènes. De récentes études ont montré que près de la moitié de tous les puits américains testés, captés pour l'eau potable, sont soumis à une contamination fécale. Une fraction significative de l'ensemble des premières manifestations de maladies liées à l'eau est associée aux eaux souterraines. On estime qu'entre 750 000 et 5,9millions de personnes sont malades chaque année aux États-Unis à cause d'eaux souterraines polluées. La mortalité parmi ces malades doit ètre de l'ordre de 1400 à 9400 décès par an. La protection contre ces germes pathogènes commence avec des mesures prises au niveau du captage pour empècher la pollution des aquifères et des puits. Celles-ci comprennent une évaluation de la vulnérabilité des tètes de puits à la pollution fécale et une correction des insuffisances mises en évidence. Cette correction peut comprendre une maîtrise des sources

  6. Influence of secondary water supply systems on microbial community structure and opportunistic pathogen gene markers.

    Science.gov (United States)

    Li, Huan; Li, Shang; Tang, Wei; Yang, Yang; Zhao, Jianfu; Xia, Siqing; Zhang, Weixian; Wang, Hong

    2018-06-01

    Secondary water supply systems (SWSSs) refer to the in-building infrastructures (e.g., water storage tanks) used to supply water pressure beyond the main distribution systems. The purpose of this study was to investigate the influence of SWSSs on microbial community structure and the occurrence of opportunistic pathogens, the latter of which are an emerging public health concern. Higher numbers of bacterial 16S rRNA genes, Legionella and mycobacterial gene markers were found in public building taps served by SWSSs relative to the mains, regardless of the flushing practice (P water retention time, warm temperature and loss of disinfectant residuals promoted microbial growth and colonization of potential pathogens in SWSSs. Varied levels of microbial community shifts were found in different types of SWSSs during water transportation from the distribution main to taps, highlighting the critical role of SWSSs in shaping the drinking water microbiota. Overall, the results provided insight to factors that might aid in controlling pathogen proliferation in real-world water systems using SWSSs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Biomimicry of volatile-based microbial control for managing emerging fungal pathogens.

    Science.gov (United States)

    Gabriel, K T; Joseph Sexton, D; Cornelison, C T

    2018-05-01

    Volatile organic compounds (VOCs) are known to be produced by a wide range of micro-organisms and for a number of purposes. Volatile-based microbial inhibition in environments such as soil is well-founded, with numerous antimicrobial VOCs having been identified. Inhibitory VOCs are of interest as microbial control agents, as low concentrations of gaseous VOCs can elicit significant antimicrobial effects. Volatile organic compounds are organic chemicals typically characterized as having low molecular weight, low solubility in water, and high vapour pressure. Consequently, VOCs readily evaporate to the gaseous phase at standard temperature and pressure. This contact-independent antagonism presents unique advantages over traditional, contact-dependent microbial control methods, including increased surface exposure and reduced environmental persistence. This approach has been the focus of our recent research, with positive results suggesting it may be particularly promising for the management of emerging fungal pathogens, such as the causative agents of white-nose syndrome of bats and snake fungal disease, which are difficult or impossible to treat using traditional approaches. Here, we review the history of volatile-based microbial control, discuss recent progress in formulations that mimic naturally antagonistic VOCs, outline the development of a novel treatment device, and highlight areas where further work is needed to successfully deploy VOCs against existing and emerging fungal pathogens. © 2017 The Society for Applied Microbiology.

  8. Isolation of pathogenic Escherichia coli from buffalo meat sold in Parbhani city, Maharashtra, India

    OpenAIRE

    M. S. Vaidya; N. M. Markandeya; R. N. Waghamare; C. S. Shekh; V. V. Deshmukh

    2013-01-01

    Aim: Isolation, characterization, in-vitro pathogenicity and antibiogram study of E.coli from buffalo meat sold in Parbhani city. Materials and Methods: Meat samples were collected from buffalo immediately after slaughter. Isolation, identification and enumeration of E. coli were done by following standard methods and protocols. Hemolysin test and Congo red binding assay were used to study in-vitro pathogenicity of E. coli isolates. Disc diffusion method was used to study antibiogram of patho...

  9. Isolation and identification of bacterial pathogen from mastitis milk in Central Java Indonesia

    Science.gov (United States)

    Harjanti, D. W.; Ciptaningtyas, R.; Wahyono, F.; Setiatin, ET

    2018-01-01

    Mastitis is a multi-etiologic disease of the mammary gland characterized mainly by reduction in milk production and milk quality due to intramammary infection by pathogenic bacteria. Nearly 83% of lactating dairy cows in Indonesia are infected with mastitis in various inflammation degrees. This study was conducted to isolate and identify the pathogen in milk collected from mastitis-infected dairy cows. The study was carried out in ten smallholder dairy farms in Central Java Indonesia based on animal examination, California mastitis test, isolation bacterial pathogens, Gram staining, Catalase and Coagulase test, and identification of bacteria species using Vitek. Bacteriological examination of milk samples revealed 15 isolates where Streptococcus was predominant species (73.3%) and the coagulase negative Staphylococcus species was identified at the least bacteria (26.7%). The Streptococcus bacteria found were Streptococcus uberis (2 isolates), Streptococcus sanguinis(6 isolates), Streptococcus dysgalactiaessp dysgalactiae(1 isolate) , Streptococcus mitis (1 isolate) and Streptococcus agalactiae (1 isolate). The Staphylococcus isolates comprising of Staphylococcus simulans (1 isolate) and Staphylococcus chromogens (3 isolates). Contamination of raw milkwith pathogenic bacteria can cause outbreaks of human disease (milk borne disease). Thus, proper milk processing method that couldinhibit the growth or kill these pathogenic bacteria is important to ensure the safety of milk and milk products.

  10. Fusarium proliferatum isolated from garlic in Spain: identification, toxigenic potential and pathogenicity on related Allium species

    Directory of Open Access Journals (Sweden)

    Daniel PALMERO

    2012-05-01

    Full Text Available Fusarium proliferatum has been reported on garlic in the Northwest USA, Spain and Serbia, causing water-soaked tan-colored lesions on cloves. In this work, Fusarium proliferatum was isolated from 300 symptomatic garlic bulbs. Morphological identification of Fusarium was confirmed using species-specific PCR assays and EF-1α sequencing. Confirmation of pathogenicity was conducted with eighteen isolates. Six randomly selected F. proliferatum isolates from garlic were tested for specific pathogenicity and screened for fusaric acid production. Additionally, pathogenicity of each F. proliferatum isolate was tested on healthy seedlings of onion (Allium cepa, leek (A. porrum, scallions (A. fistulosum, chives (A. schoenoprasum and garlic (A. sativum. A disease severity index (DSI was calculated as the mean severity on three plants of each species with four test replicates. Symptoms on onion and garlic plants were observed three weeks after inoculation. All isolates tested produced symptoms on all varieties inoculated. Inoculation of F. proliferatum isolates from diseased garlic onto other Allium species provided new information on host range and pathogenicity. The results demonstrated differences in susceptibility with respect to host species and cultivar. The F. proliferatum isolates tested all produced fusaric acid (FA; correlations between FA production and isolate pathogenicity are discussed. Additionally, all isolates showed the presence of the FUM1 gene suggesting the ability of Spanish isolates to produce fumonisins.

  11. Isolation and characterization of pathogenic leptospires associated with cattle

    Science.gov (United States)

    Pathogenic leptospires colonize the renal tubules of reservoir hosts of infection, including cattle, and are excreted via urine. In order to identify circulating serovars of pathogenic leptospires in beef cattle, and their associated rates of urinary excretion, a cross sectional study was performed....

  12. Antibiogram profile of pathogens isolated from processed cow meat ...

    African Journals Online (AJOL)

    ... the antibiotic resistance tests revealed varied, but interesting susceptibility patterns. Our findings does highlight the fact that there exist obvious vehicles for pathogenic bacteria proliferation within our abattoirs, and hence, the need for caution. Key words: Abattoirs, Bos taurus, Pathogenic bacteria, Antibiotics, Resistance ...

  13. Draft genomic sequencing of six potential extraintestinal pathogenic Escherichia coli isolates from retail chicken meat.

    Science.gov (United States)

    Potential Extraintestinal pathogenic Escherichia coli isolates DP254, WH333, WH398, F356, FEX675 and FEX725 were isolated from retail chicken meat products. Here, we report the draft genome sequences for these six E. coli isolates, which are currently being used in food safety research....

  14. Climate change and the potential spreading of marine mucilage and microbial pathogens in the Mediterranean Sea.

    Directory of Open Access Journals (Sweden)

    Roberto Danovaro

    2009-09-01

    Full Text Available Marine snow (small amorphous aggregates with colloidal properties is present in all oceans of the world. Surface water warming and the consequent increase of water column stability can favour the coalescence of marine snow into marine mucilage, large marine aggregates representing an ephemeral and extreme habitat. Marine mucilage characterize aquatic systems with altered environmental conditions.We investigated, by means of molecular techniques, viruses and prokaryotes within the mucilage and in surrounding seawater to examine the potential of mucilage to host new microbial diversity and/or spread marine diseases. We found that marine mucilage contained a large and unexpectedly exclusive microbial biodiversity and hosted pathogenic species that were absent in surrounding seawater. We also investigated the relationship between climate change and the frequency of mucilage in the Mediterranean Sea over the last 200 years and found that the number of mucilage outbreaks increased almost exponentially in the last 20 years. The increasing frequency of mucilage outbreaks is closely associated with the temperature anomalies.We conclude that the spreading of mucilage in the Mediterranean Sea is linked to climate-driven sea surface warming. The mucilage can act as a controlling factor of microbial diversity across wide oceanic regions and could have the potential to act as a carrier of specific microorganisms, thereby increasing the spread of pathogenic bacteria.

  15. Beneficial and Harmful Interactions of Antibiotics with Microbial Pathogens and the Host Innate Immune System

    Directory of Open Access Journals (Sweden)

    Ronald Anderson

    2010-05-01

    Full Text Available In general antibiotics interact cooperatively with host defences, weakening and decreasing the virulence of microbial pathogens, thereby increasing vulnerability to phagocytosis and eradication by the intrinsic antimicrobial systems of the host. Antibiotics, however, also interact with host defences by several other mechanisms, some harmful, others beneficial. Harmful activities include exacerbation of potentially damaging inflammatory responses, a property of cell-wall targeted agents, which promotes the release of pro-inflammatory microbial cytotoxins and cell-wall components. On the other hand, inhibitors of bacterial protein synthesis, especially macrolides, possess beneficial anti-inflammatory/cytoprotective activities, which result from interference with the production of microbial virulence factors/cytotoxins. In addition to these pathogen-directed, anti-inflammatory activities, some classes of antimicrobial agent possess secondary anti-inflammatory properties, unrelated to their conventional antimicrobial activities, which target cells of the innate immune system, particularly neutrophils. This is a relatively uncommon, potentially beneficial property of antibiotics, which has been described for macrolides, imidazole anti-mycotics, fluoroquinolones, and tetracyclines. Although of largely unproven significance in the clinical setting, increasing awareness of the pro-inflammatory and anti-inflammatory properties of antibiotics may contribute to a more discerning and effective use of these agents.

  16. Characterization and isolation of an extracellular serine protease from the tomato pathogen Colletotrichum coccodes, and it's role in pathogenicity

    Science.gov (United States)

    Redman, Regina S.; Rodriguez, Rusty J.

    2002-01-01

    Extracellular enzymes play an important role in the pathogenicity and virulence of phytopathogenic fungi. Several isolates of Colletotrichum coccodes causal agent of anthracnose on tomato, were screened to determine the relationship between protease activity and virulence. A direct relationship was observed between extracellular protease activity and the induction of disease symptoms of fruit and mortality in plants. Isolate Cc155 exhibited the highest protease activity after five days of growth in protease induction medium and produced an extracellular serine protease (sp78) that was 78 kDa, auto-degradative, glucose repressible, and non-glycosylated. To determine the role of sp78 in pathogenicity, a UV-induced extracellular protease deficient mutant (np155) was generated from the wildtype isolate Cc155. Np155 maintained growth rates comparable to Cc155 and produced wildtype levels of extracellular cellulase but did not produce extracellular protease. Unlike Cc155, np155 caused no disease symptoms on tomato fruit and 0% mortality on tomato seedlings. These results suggest that extracellular protease activity is required for pathogenicity and virulence of C. coccodes and that the elimination of protease activity transforms a virulent pathogen to a non-pathogenic endophyte.

  17. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum

    Science.gov (United States)

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-01-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. PMID:24311557

  18. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum.

    Science.gov (United States)

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-12-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. © 2013 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  19. Microbial Murders Crime Scene Investigation: An Active Team-Based Learning Project that Enhances Student Enthusiasm and Comprehension of Clinical Microbial Pathogens.

    Science.gov (United States)

    Steel, J Jordan

    2017-01-01

    Microbial disease knowledge is a critical component of microbiology courses and is beneficial for many students' future careers. Microbiology courses traditionally cover core concepts through lectures and labs, but specific instruction on microbial diseases varies greatly depending on the instructor and course. A common project involves students researching and presenting a disease to the class. This method alone is not very effective, and course evaluations have consistently indicated that students felt they lacked adequate disease knowledge; therefore, a more hands-on and interactive disease project was developed called Microbial Murders. For this team-based project, a group of students chooses a pathogen, researches the disease, creates a "mugshot" of the pathogen, and develops a corresponding "crime scene," where a hypothetical patient has died from the microbe. Each group gives a presentation introducing the microbial pathogen, signs/symptoms, treatments, and overall characteristics. The students then visit each other's crime scenes to match the pathogen with the correct crime scene by critically thinking through the clues. This project has shown remarkable success. Surveys indicate that 73% of students thought the project helped them understand the material and 84% said it was worth their time. Student participation, excitement, understanding, and application of microbial disease knowledge have increased and are evident through an increase in course evaluations and in student assessment scores. This project is easy to implement and can be used in a wide variety of biology, microbiology, or health classes for any level (middle school through college).

  20. Transmutation of Personal Glucose Meters into Portable and Highly Sensitive Microbial Pathogen Detection Platform.

    Science.gov (United States)

    Wang, Zhenzhen; Chen, Zhaowei; Gao, Nan; Ren, Jinsong; Qu, Xiaogang

    2015-10-07

    Herein, for the first time, we presented a simple and general approach by using personal glucose meters (PGM) for portable and ultrasensitive detection of microbial pathogens. Upon addition of pathogenic bacteria, glucoamylase-quaternized magnetic nanoparticles (GA-QMNPS) conjugates were disrupted by the competitive multivalent interactions between bacteria and QMNPS, resulting in the release of GA. After magnetic separation, the free GA could catalyze the hydrolysis of amylose into glucose for quantitative readout by PGM. In such way, PGM was transmuted into a bacterial detection device and extremely low detection limits down to 20 cells mL(-1) was achieved. More importantly, QMNPS could inhibit the growth of the bacteria and destroy its cellular structure, which enabled bacteria detection and inhibition simultaneously. The simplicity, portability, sensitivity and low cost of presented work make it attractive for clinical applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Isolation and application of hydrocarbon degradation of indigenous microbial from oil contaminated soil

    International Nuclear Information System (INIS)

    Dadang Sudrajat; Nana Mulyana; Tri Retno DL

    2015-01-01

    The aims of this research are to obtain indigenous potential microbes from bacterial and fungal groups which have capable of degrading hydrocarbon from crude oil contaminated soil. The research carried out were isolation, selection, and identification potential microbial isolates capable of degrading hydrocarbon from oil contaminated soil located at Cepu East Java. The isolates were tested for their growth and ability to degrades crude oil. Each isolate was inoculated unto minimum mineral salt medium (MSM) contained 1% crude oil. Viability and stability test of selected isolates were carried out on irradiated compost carrier materials contained 5% crude oil. The fours series microbial s consortium consists of microbial consortium I, II, III, and IV were tested for the in vitro biodegradability of hydrocarbon. The results shows there sixty two (62) isolates are obtained, among them 42 bacteria and 20 molds. From 42 bacterial isolates, only 8 strains were potent hydrocarbon degraders. Three of these isolates are identified Bacillus cereus (BMC2), Bacillus sp (BMC4), and Pseudomonas sp (BMC6). Whereas from 20 fungal isolates, only 4 strains were potent hydrocarbon degraders. Two of these isolates are identified Aspergillus fumigatus (FMC2) and Aspergillus niger (FMC6). All isolates show good growth in mineral salt medium contained crude oil with decrease in pH. The ability of decrease of TPH content by the bacterial and fungal isolates were 54, 61, 67, 74, and 78% respectively at day 30. The viability and stability of microbial isolates show considerable good viability on irradiated compost carrier materials after 14 days storage. From the fours series microbial consortium, the highest TPH degradation rates is found in microbial consortium III (BMC6, BMC2, and FMC6) with 89,1% in 5 weeks. (author)

  2. Analysis of pathogenic factors of Proteus mirabilis isolated from urinary tract infection

    OpenAIRE

    室谷,勝久

    1991-01-01

    Proteus mirabilis has several pathogenic factors such as adherent ability to urinary tract epitherial cells, urease, motility and resistance to urine. The pathogenic activities of clinically isolated P. mirabilis were analyzed. Higher pathogenic strains (No. 25 and No. 30) which had morphologically different pili but had a higher density of pili showed strong adherent activity to bladder epithelial cells of mouse and rat. These strains also showed a clear chemotaxis to urinary tract tissue ex...

  3. Genome sequence of the pathogenic Herbaspirillum seropedicae strain Os34, isolated from rice roots.

    Science.gov (United States)

    Ye, Weijun; Ye, Shuting; Liu, Jian; Chang, Siping; Chen, Mingyue; Zhu, Bo; Guo, Longbiao; An, Qianli

    2012-12-01

    Most Herbaspirillum seropedicae strains are beneficial endophytes to plants. In contrast, H. seropedicae strain Os34, isolated from rice roots, is pathogenic. The draft genome sequence of strain Os34 presented here allows in-depth comparative genome analyses to understand the specific mechanisms of beneficial and pathogenic Herbaspirillum-plant interactions.

  4. Genome sequence of the pathogenic Herbaspirillum seropedicae strain Os45, isolated from rice roots.

    Science.gov (United States)

    Zhu, Bo; Ye, Shuting; Chang, Siping; Chen, Mingyue; Sun, Li; An, Qianli

    2012-12-01

    Most Herbaspirillum seropedicae strains are beneficial to plants. In contrast, H. seropedicae strain Os45, isolated from rice roots, is pathogenic. The draft genome sequence of strain Os45 presented here allows an in-depth comparative genome analysis to understand the subtle mechanisms of beneficial and pathogenic Herbaspirillum-plant interactions.

  5. Microbial Observatory (ISS-MO): Study of BSL-2 bacterial isolates from the International Space Station

    Data.gov (United States)

    National Aeronautics and Space Administration — In an on-going Microbial Observatory experimental investigation on the International Space Station (ISS) multiple bacterial isolates of Biosafety Level 2 (BSL-2)...

  6. ISOLATION AND PATHOGENICITY OF A POSSIBLE Pythium aphanidermatum IN Jatropha Curcas L. NON TOXIC

    Directory of Open Access Journals (Sweden)

    Ofelia Andrea Valdes Rodriguez

    2011-03-01

    A chromista, possible Pythium aphanidermatum, was isolated from severely damage seeds and seedlings recently started from Jatropha curcas L. non toxic seeds sown in the tropical area of Veracruz, Mexico. In order to study pathogenic Pythium aphanidermatum effects over pre-emergent and post-emergent stages, seeds and young seedlings were inoculated with the isolated pathogen, and the chromista showed possible pathogenic activity against pre-emergency and recently started post-emergency; however, statistically significant damaged was not found in older seedlings.   Â

  7. Diversity of Urinary Tract Pathogens and Drug Resistant Isolates of ...

    African Journals Online (AJOL)

    Purpose: This paper was mainly aimed to investigate drug resistance of the various urinary tract infection (UTI) pathogens from patients of different gender and age groups of Pakistanis. Method: For these purposes, urine samples of 109 patients were analyzed. Samples were screened on CLED agar. Antimicrobial ...

  8. Pathogenic potential of Listeria monocytogenes isolated from cattle ...

    African Journals Online (AJOL)

    Listeria monocytogenes is an opportunistic food-borne pathogen causing listeriosis especially among immune-compromised persons. Its high rate of morbidity and mortality has classed the organism among the top watch list in foods. It is known to produce several virulence factors which aid its survival in harsh conditions ...

  9. Opportunistic Pathogens and Microbial Communities and Their Associations with Sediment Physical Parameters in Drinking Water Storage Tank Sediments

    Science.gov (United States)

    Qin, Ke; Struewing, Ian; Domingo, Jorge Santo; Lytle, Darren

    2017-01-01

    The occurrence and densities of opportunistic pathogens (OPs), the microbial community structure, and their associations with sediment elements from eight water storage tanks in Ohio, West Virginia, and Texas were investigated. The elemental composition of sediments was measured through X-ray fluorescence (XRF) spectra. The occurrence and densities of OPs and amoeba hosts (i.e., Legionella spp. and L. pneumophila, Mycobacterium spp., P. aeruginosa, V. vermiformis, Acanthamoeba spp.) were determined using genus- or species-specific qPCR assays. Microbial community analysis was performed using next generation sequencing on the Illumina Miseq platform. Mycobacterium spp. were most frequently detected in the sediments and water samples (88% and 88%), followed by Legionella spp. (50% and 50%), Acanthamoeba spp. (63% and 13%), V. vermiformis (50% and 25%), and P. aeruginosa (0 and 50%) by qPCR method. Comamonadaceae (22.8%), Sphingomonadaceae (10.3%), and Oxalobacteraceae (10.1%) were the most dominant families by sequencing method. Microbial communities in water samples were mostly separated with those in sediment samples, suggesting differences of communities between two matrices even in the same location. There were associations of OPs with microbial communities. Both OPs and microbial community structures were positively associated with some elements (Al and K) in sediments mainly from pipe material corrosions. Opportunistic pathogens presented in both water and sediments, and the latter could act as a reservoir of microbial contamination. There appears to be an association between potential opportunistic pathogens and microbial community structures. These microbial communities may be influenced by constituents within storage tank sediments. The results imply that compositions of microbial community and elements may influence and indicate microbial water quality and pipeline corrosion, and that these constituents may be important for optimal storage tank management

  10. Identification and characterization of novel natural pathogen of Drosophila melanogaster isolated from wild captured Drosophila spp.

    Science.gov (United States)

    Singh, Karan; Zulkifli, Mohammad; Prasad, N G

    2016-12-01

    Drosophila melanogaster is an emerging model system for the study of evolutionary ecology of immunity. However, a large number of studies have used non natural pathogens as very few natural pathogens have been isolated and identified. Our aim was to isolate and characterize natural pathogen/s of D. melanogaster. A bacterial pathogen was isolated from wild caught Drosophila spp., identified as a new strain of Staphylococcus succinus subsp. succinus and named PK-1. This strain induced substantial mortality (36-62%) in adults of several laboratory populations of D. melanogaster. PK-1 grew rapidly within the body of the flies post infection and both males and females had roughly same number of colony forming units. Mortality was affected by mode of infection and dosage of the pathogen. However mating status of the host had no effect on mortality post infection. Given that there are very few known natural bacterial pathogens of D. melanogaster and that PK-1 can establish a sustained infection across various outbred and inbred populations of D. melanogaster this new isolate is a potential resource for future studies on immunity. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  11. Anti-Microbial Resistance Profiles Of E. Coli Isolated From Free Range Chickens In Urban And Rural Environments Of Imo State, Nigeria

    OpenAIRE

    Okoli I, Dr. Charles

    2006-01-01

    Information on the resistance profiles of normal intestinal flora of extensively reared chickens that hardly receive antibiotics in the developing countries can serve as important means of understanding the human/animal pathogens drug resistance interactions in the zone. Three hundred and fifty E. coli isolates, comprising 133 from urban and 217 from rural sites in Imo state, Nigeria, were screened for anti-microbial resistance profile against 10 antibiotics using the disc diffusion method. O...

  12. Isolation of a highly pathogenic influenza virus from turkeys.

    Science.gov (United States)

    McNulty, M S; Allan, G M; McCracken, R M; McParland, P J

    1985-01-01

    An influenza virus was isolated from turkeys with an acute disease causing 30% mortality. The virus was subtyped as H5 N8. The nomenclature A/turkey/Ireland/83 (H5 N8) is proposed for this isolate. The virus had an ICPI of 1.80 to 1.85 for 1-day-old chicks and an IVPI of 2.74 for 6-week-old chickens. Following oronasal inoculation of juvenile and adult turkeys, chickens and ducks with the isolate, 100% mortality occurred in turkeys and chickens. No clinical signs were observed in inoculated ducks, but all developed serum antibody titres against the virus.

  13. Phenotypic and molecular typing of Vibrio harveyi isolates and their pathogenicity to tiger shrimp larvae.

    Science.gov (United States)

    Alavandi, S V; Manoranjita, V; Vijayan, K K; Kalaimani, N; Santiago, T C

    2006-11-01

    The objective of the present study was to identify the biotype(s) and molecular type(s) of Vibrio harveyi associated with pathogenicity in tiger shrimp (Penaeus monodon) larvae. Five luminescent and four nonluminescent V. harveyi isolates were subjected to phenotyping and random amplified polymorphic DNA (RAPD) fingerprinting, and pathogenicity testing to P. monodon mysis. Four isolates induced 34-41% mortality of P. monodon mysis when challenged at the rate of 10(6) CFU ml(-1) within 60 h. Sucrose-fermenting biotypes of V. harveyi appeared to be associated with pathogenicity to larval shrimp. Higher temperature and salinity appeared to play a role on the onset of vibriosis and mortality in the challenged larval shrimp. Pathogenic isolates of V. harveyi could be demarcated as revealed by their clustering in the dendrogram constructed based on the RAPD fingerprints. Nonluminescent V. harveyi also appear to be important aetiological agents of vibriosis of shrimp larvae. Sucrose-fermenting biotypes are likely to be pathogenic. High temperature may trigger onset of vibriosis. Biotyping of V. harveyi isolates and looking for traits, such as ability to ferment sucrose may be helpful in identifying the pathogenic forms, and such approach requires to be investigated further with larger number of isolates.

  14. In vitro anticancer activity of microbial isolates from diverse habitats

    Directory of Open Access Journals (Sweden)

    Angel Treasa Thomas

    2011-06-01

    Full Text Available Extracts from natural products, especially microorganisms, have served as a valuable source of diverse molecules in many drug discovery efforts and led to the discovery of several important drugs. Identification of microbial strains having promising biological activities and purifying the bio-molecules responsible for the activities, have led to the discovery of many bioactive molecules. Extracellular, as well as intracellular, extracts of the metabolites of thirty-six bacterial and twenty-four fungal isolates, grown under unusual conditions such as high temperature, high salt and low sugar concentrations, were in vitro tested for their cytotoxic potential on various cancer cell lines. The extracts were screened on HeLa and MCF-7 cell lines to study the cytotoxic potential. Nuclear staining and flow cytometric studies were carried out to assess the potential of the extracts in arresting the cell cycle. The crude ethylacetate extract of isolate F-21 showed promising results by MTT assay with IC50 as low as 20.37±0.36 µg/mL on HeLa, and 44.75±0.81 µg/mL on MCF-7 cells, comparable with Cisplatin. The isolate F-21 was identified as Aspergillus sp. Promising results were also obtained with B-2C and B-4E strains. Morphological studies, biochemical tests and preliminary chemical investigation of the extracts were also carried out.Extratos de produtos naturais, especialmente de microrganismos, constituíram-se em fonte valiosa de diversas moléculas em muitas descobertas de fármacos e levaram à descoberta de fármacos importantes. A identificação de espécies microbianas que apresentam atividade biológica e a purificação de biomoléculas responsáveis pelas atividades levou à descoberta de muitas moléculas bioativas. Extratos extracelulares tanto quanto intracelulares de metabólitos de 36 isolados de bactérias e 24 isolados de fungos, que cresceram sob condições não usuais, como alta temperatura, alta concentração de sal e baixa

  15. Highly pathogenic avian influenza virus (H5N1) isolated from whooper swans, Japan.

    Science.gov (United States)

    Uchida, Yuko; Mase, Masaji; Yoneda, Kumiko; Kimura, Atsumu; Obara, Tsuyoshi; Kumagai, Seikou; Saito, Takehiko; Yamamoto, Yu; Nakamura, Kikuyasu; Tsukamoto, Kenji; Yamaguchi, Shigeo

    2008-09-01

    On April 21, 2008, four whooper swans were found dead at Lake Towada, Akita prefecture, Japan. Highly pathogenic avian influenza virus of the H5N1 subtype was isolated from specimens of the affected birds. The hemagglutinin (HA) gene of the isolate belongs to clade 2.3.2 in the HA phylogenetic tree.

  16. Pathogenicity of Fusarium avenaceum isolates to tulip leaves assessed on leaf disks

    Directory of Open Access Journals (Sweden)

    Agnieszka Piwoni

    2013-12-01

    Full Text Available The purpose of this study was to investigate the pathogenicity of 14 Fusarium avenaceum (Giberella avenacea isolates, obtained from tulip plantations located in Puławy region, to leaves of tulip cv. Apeldoorn. Mycelial plugs 3 mm in diameter from the margins of the colonies growing on PDA and SNA were placed on 20 mm disks cut from tulip leaves. The disks were placed abaxial surface up, in Petri dishes on top of filter paper soaked with 100 mg/l gibberellic acid to retard leaf senescence. There were 5 replications for each isolate. Leaves in each Petń dish were inoculated with one isolate. Plates were incubated at 20°C and lesion diameters were measured after 4 days. The pathogenicity of investigated isolates was compared by measuring lesion development on tulip leaves. All of isolates colonized leaves disks succesfull - causing after 4 days necrotic lesions and sporulating after 14 days what indicated that an infection had occurred. There were significant differences in lesions size among isolates. Isolates: 27, 1, 2, 48 and 3 caused largest lesions at mean size from 150 mm2 to 163 mm2 what indicates their high pathogenicity. Less pathogenic were isolates: 28, 42, 7 and 72 caused lesions at mean size from 46 mm2 to 97 mm~2. On average, mycelial plugs taken from PDA medium colonized leaf disks more efficient in comparison to them taken from SNA, that caused smaller lesions.

  17. HSQC-TOCSY Fingerprinting for Prioritization of Polyketide- and Peptide-Producing Microbial Isolates.

    Science.gov (United States)

    Buedenbender, Larissa; Habener, Leesa J; Grkovic, Tanja; Kurtböke, D İpek; Duffy, Sandra; Avery, Vicky M; Carroll, Anthony R

    2018-04-27

    Microbial products are a promising source for drug leads as a result of their unique structural diversity. However, reisolation of already known natural products significantly hampers the discovery process, and it is therefore important to incorporate effective microbial isolate selection and dereplication protocols early in microbial natural product studies. We have developed a systematic approach for prioritization of microbial isolates for natural product discovery based on heteronuclear single-quantum correlation-total correlation spectroscopy (HSQC-TOCSY) nuclear magnetic resonance profiles in combination with antiplasmodial activity of extracts. The HSQC-TOCSY experiments allowed for unfractionated microbial extracts containing polyketide and peptidic natural products to be rapidly identified. Here, we highlight how this approach was used to prioritize extracts derived from a library of 119 ascidian-associated actinomycetes that possess a higher potential to produce bioactive polyketides and peptides.

  18. PATHOGENICITY OF FUSARIUM SPP. ISOLATED FROM WEEDS AND PLANT DEBRIS IN EASTERN CROATIA TO WHEAT AND MAIZE

    Directory of Open Access Journals (Sweden)

    Jelena Ilić

    2012-12-01

    Full Text Available Pathogenicity of thirty isolates representing 14 Fusarium species isolated from weeds and plant debris in eastern Croatia was investigated in the laboratory. Pathogenicity tests were performed on wheat and maize seedlings. The most pathogenic Fusarium spp. was F. graminearum isolated from Amaranthus retroflexus, Abutilon theophrasti and Chenopodium album. There was a noticeable inter- and intraspecies variability in pathogenicity towards wheat and maize. Isolates of F. solani from Sonchus arvensis and F. verticillioides from C. album were highly pathogenic to wheat seedlings and apathogenic to maize seedlings. Isolates of F. venenatum were very pathogenic to wheat and maize being the first report about pathogenicity of this species. This experiment proves that weeds and plant debris can serve as alternate hosts and source of inoculum of plant pathogens.

  19. Microbial Inhibition of Fusarium Pathogens and Biological Modification of Trichothecenes in Cereal Grains

    Directory of Open Access Journals (Sweden)

    Urszula Wachowska

    2017-12-01

    Full Text Available Fungi of the genus Fusarium infect cereal crops during the growing season and cause head blight and other diseases. Their toxic secondary metabolites (mycotoxins contaminate grains. Several dozen toxic compounds produced by fungal pathogens have been identified to date. Type B trichothecenes—deoxynivalenol, its acetyl derivatives and nivalenol (produced mainly by F. graminearum and F. culmorum—are most commonly detected in cereal grains. “T-2 toxin” (produced by, among others, F. sporotrichioides belongs to type-A trichothecenes which are more toxic than other trichothecenes. Antagonistic bacteria and fungi can affect pathogens of the genus Fusarium via different modes of action: direct (mycoparasitism or hyperparasitism, mixed-path (antibiotic secretion, production of lytic enzymes and indirect (induction of host defense responses. Microbial modification of trichothecenes involves acetylation, deacetylation, oxidation, de-epoxidation, and epimerization, and it lowers the pathogenic potential of fungi of the genus Fusarium. Other modifing mechanisms described in the paper involve the physical adsorption of mycotoxins in bacterial cells and the conjugation of mycotoxins to glucose and other compounds in plant and fungal cells. The development of several patents supports the commercialization and wider application of microorganisms biodegrading mycotoxins in grains and, consequently, in feed additives.

  20. Microbial Pathogens Implicated in Reproductive Health Infections in a Special Treatment Clinic in Ibadan, Nigeria

    Directory of Open Access Journals (Sweden)

    Adenike Ogunshe

    2009-03-01

    Full Text Available Objective: The lack of adequate recognition of health importance of non-HIV reproductive health infections (RHIs in Nigeria has led into this study, which was to determine clinical pathogens in non-HIV RHI in Nigeria using a tertiary health facility as case study.Materials and Methods: A nine-year investigation was carried out between 1997 and 2005 on 4047 (n = 1626 males; n = 2421 females patients presenting at Special Treatment Clinic (STC of University College Hospital (UCH Ibadan, Nigeria. Routine laboratory procedures using appropriate culture media, culture conditions, and current phenotypic taxonomic tools for classification of isolated pathogens were employed.Results: Age (p = 0.019 and gender (p<0.0001 were related to the recovery rates of pathogens Candida species (55.6 %, Neisseria gonorrhoae (11.1%, Gardenella vaginalis (10.3%, Escherichia coli (9.2 %, Klebsiella sp. (4.2%, streptococci (4.0%, Staphylococcus aureus (2.3%, Proteus sp., (1.8%, Haemophilus ducreyi (0.5%, Trichomonas vaginalis (0.44% and Pseudomonas aeruginosa (0.18%. Candida and Gardenella vaginalis species were mostly recovered from female patients, while N.gonorrhoeae were mostly isolated from male patients. Age brackets for the recovery of pathogens were Neisseria gonorrhoeae (16-30 years; Gardenella vaginalis (21-25 and 31-35 years and C.albicans (21-30 years.Conclusion: Candida, Neisseria gonorrhoea and Gadrenella vaginalis were the most recovered pathogens from patients presenting at Special Treatment Clinic of a tertiary health institution in Nigeria, and the relationship between age, gender and the aetiological agents was statistically significant.

  1. Pathogenicity of isolates of Colletotrichum spp.: The causal agents of anthracnose

    OpenAIRE

    Živković, Svetlana; Dolovac, Nenad; Popović, Tatjana; Stojanović, Saša

    2012-01-01

    The pathogenic characteristics of 20 isolates of Colletotrichum spp. originating from pear, apple, sour cherry and tomato fruits, as well as reference strains of C. acutatum (CBS 294.67) and C. gloeosporioides (CBS 516.97) are presented in this paper. In the studies of host range of isolates of Colletotrichum spp. were included 17 plant species. Nine days after artificial inoculation all tested isolates were caused anthracnose lesion on fruits of apple, pear, peach, apricot, sour cherry, swee...

  2. Etiology and pathogenicity of two different isolates of Colletotrichum spp. obtained from physic nut seeds

    OpenAIRE

    Santos,Gil Rodrigues dos; Tozze Júnior,Hugo José; Sá,Danila Alves Corrêa de; Furtado,Gleiber Quintão; Massola Júnior,Nelson Sidnei

    2013-01-01

    The species known as physic nut (Jatropha curcas L.) has become important as one of main sources of feedstock for biodiesel production. The aims of this study were characterizing two different isolates of Colletotrichum spp. obtained from seeds of this species, through morphological, cultural, and molecular analyses; as well as assessing pathogenicity of both isolates on leaves and fruit of this plant species. For morphological analysis, length and width of 30 spores of each isolate, produced...

  3. Evaluation of isolation methods for pathogenic Yersinia enterocolitica from pig intestinal content.

    Science.gov (United States)

    Laukkanen, R; Hakkinen, M; Lundén, J; Fredriksson-Ahomaa, M; Johansson, T; Korkeala, H

    2010-03-01

    The aim of this study was to evaluate the efficiency of four isolation methods for the detection of pathogenic Yersinia enterocolitica from pig intestinal content. The four methods comprised of 15 isolation steps using selective enrichments (irgasan-ticarcillin-potassium chlorate and modified Rappaport broth) and mildly selective enrichments at 4 or 25 degrees C. Salmonella-Shigella-desoxycholate-calcium chloride agar, cefsulodin-irgasan-novobiocin agar were used as plating media. The most sensitive method detected 78% (53/68) of the positive samples. Individual isolation steps using cold enrichment as the only enrichment or as a pre-enrichment step with further selective enrichment showed the highest sensitivities (55-66%). All isolation methods resulted in high numbers of suspected colonies not confirmed as pathogenic Y. enterocolitica. Cold enrichment should be used in the detection of pathogenic Y. enterocolitica from pig intestinal contents. In addition, more than one parallel isolation step is needed. The study shows that depending on the isolation method used for Y. enterocolitica, the detected prevalence of Y. enterocolitica in pig intestinal contents varies greatly. More selective and sensitive isolation methods need to be developed for pathogenic Y. enterocolitica.

  4. Morphological and molecular characterization, sexual reproduction, and pathogenicity of Setosphaeria rostrata isolates from rice leaf spot.

    Science.gov (United States)

    Kusai, Nor Azizah; Azmi, Madihah Mior Zakuan; Zainudin, Nur Ain Izzati Mohd; Yusof, Mohd Termizi; Razak, Azmi Abd

    2016-09-01

    Setosphaeria rostrata, a common plant pathogen causing leaf spot disease, affects a wide range of plant species, mainly grasses. Fungi were isolated from brown spots on rice leaves throughout Peninsular Malaysia, and 45 isolates were identified as Setosphaeria rostrata The isolates were then characterized using morphological and molecular approaches. The mating type was determined using PCR amplification of the mating type alleles, and isolates of opposite mating types were crossed to examine sexual reproduction. Based on nuclear ribosomal DNA ITS1-5.8S-ITS2 region (ITS) and beta-tubulin (BT2) sequences, two phylogenetic trees were constructed using the maximum likelihood method; S. rostrata was clustered in one well-supported clade. Pathogenicity tests showed that S. rostrata isolates are pathogenic, suggesting that it is the cause of the symptoms. Mating-type analyses indicated that three isolates carried the MAT1-1 allele, and the other 42 isolates carried MAT1-2 After isolates with opposite mating types were crossed on Sach's medium and incubated for 3 wk, six crosses produced pseudothecia that contained eight mature ascospores, and 12 other crosses produced numerous pseudothecia with no ascospores. To our knowledge, this is the first report on S. rostrata isolated from leaf spots on rice. © 2016 by The Mycological Society of America.

  5. Zoonotic pathogens isolated from wild animals and environmental samples at two California wildlife hospitals.

    Science.gov (United States)

    Siembieda, Jennifer L; Miller, Woutrina A; Byrne, Barbara A; Ziccardi, Michael H; Anderson, Nancy; Chouicha, Nadira; Sandrock, Christian E; Johnson, Christine K

    2011-03-15

    To determine types and estimate prevalence of potentially zoonotic enteric pathogens shed by wild animals admitted to either of 2 wildlife hospitals and to characterize distribution of these pathogens and of aerobic bacteria in a hospital environment. Cross-sectional study. Fecal samples from 338 animals in 2 wildlife hospitals and environmental samples from 1 wildlife hospital. Fecal samples were collected within 24 hours of hospital admission. Environmental samples were collected from air and surfaces. Samples were tested for zoonotic pathogens via culture techniques and biochemical analyses. Prevalence of pathogen shedding was compared among species groups, ages, sexes, and seasons. Bacterial counts were determined for environmental samples. Campylobacter spp, Vibrio spp, Salmonella spp, Giardia spp, and Cryptosporidium spp (alone or in combination) were detected in 105 of 338 (31%) fecal samples. Campylobacter spp were isolated only from birds. Juvenile passerines were more likely to shed Campylobacter spp than were adults; prevalence increased among juvenile passerines during summer. Non-O1 serotypes of Vibrio cholerae were isolated from birds; during an oil-spill response, 9 of 10 seabirds screened were shedding this pathogen, which was also detected in environmental samples. Salmonella spp and Giardia spp were isolated from birds and mammals; Cryptosporidium spp were isolated from mammals only. Floors of animal rooms had higher bacterial counts than did floors with only human traffic. Potentially zoonotic enteric pathogens were identified in samples from several species admitted to wildlife hospitals, indicating potential for transmission if prevention is not practiced.

  6. Isolation and identification of main mastitis pathogens in Mexico

    Directory of Open Access Journals (Sweden)

    H. Castañeda Vázquez

    2013-04-01

    Full Text Available The present work is a large epidemiological study aiming to detect the prevalence of subclinical mastitis and to investigate the major udder pathogens in Jalisco State, western Mexico. For this purpose, 2205 dairy cows, representing 33 Mexican dairy herds, were involved. Of 2205 cows, 752 mastitic animals were diagnosed and only 2,979 milk samples could be obtained for further investigation. All 2979 milk samples were subjected to California Mastitis Test (CMT to differentiate clinical cases from subclinical ones where 1996 samples (67 % reacted positively. Of these, 1087 samples (54.5% came from cows suffering from clinical cases of mastitis. Bacteriological identification of the causative agents revealed the presence of a major group of pathogens including the Coagulase negative staphylococci (CNS, S.aureus, S.agalactiae, Corynebacterium spp. and Coliform bacteria which were detected in 464 (15.6%, 175 (5.9%, 200 (6.8%, 417 (14% and 123 (4.1% of the 2927 investigated quarters, 295 (15.4%, 118 (15.7%, 111 (14.8%, 227 (30.2% and 109 (14.5% of the 752 examined cows and in 33 (100%, 22 (66.7%, 19 (57.6%, 30 (90.1% and 27 (81.8% of the 33 herds involved, respectively. Other pathogens could be detected in the investigated milk samples such as S. dysgalactiae (0.4%, S.uberis (0.37%, Bacillus spp. (1%, Nocardia spp. (0.6% und Candida spp. (0.1%. Meanwhile, others were present in a negligible ratio; including the Aerococcus viridans, and Enterococcus spp., Lactococcus lactis, S. bovis.

  7. Methylobacteria isolated from bryophytes and the 2-fold description of the same microbial species.

    Science.gov (United States)

    Schauer, S; Kutschera, U

    2013-02-01

    On the surface of healthy land plants (embryophytes), numerous non-pathogenic bacteria have been discovered and described. Among these epiphytic microbes, pink-pigmented facultative methylotrophic microbes of the genus Methylobacterium are of special significance, because these microorganisms consume methanol emitted via the stomatal pores and secrete growth-promoting phytohormones. Methylobacterium funariae, Schauer and Kutschera 2011, a species isolated in our lab from the common cord moss, described as a nova species in this journal, was recently characterized for a second time as a "new taxon" under a different name, "M. bullatum." Based on a phylogenetic analysis, we show that these taxa are identical. In addition, we provide novel information on the exact cell size, and describe the correct type locality of this bacterial species, which was classified as a phytosymbiont. Finally, we discuss the hypothesis that certain methylobacteria may preferentially colonize bryophytes. With reference to our recent discovery that thalli of ferns form, like liverworts and moss protonemata, associations with methylobacteria, we argue that the haploid phase of cryptogames are preferred host organisms of these pink-pigmented microbial phytosymbionts.

  8. Isolation and Characterization of Seed-Borne Pathogenic Bacteria

    African Journals Online (AJOL)

    76 L.K. Ashura et aI. Table 4: Selected morphological and biochemical characteristics of bacteria isolates from rice seed as de- tected by the Liquid Assay on mXOS. Ace. No.1. Fluorescentl. Kovac's. OIF. NR. GL. SH. LS. HR. Pstho. Diolog Identification lsolale(s). Colour of·. Oxidase. TIP g on. (Similarity). I. Pigment. Rice.

  9. Microbial Assessment and Prevalence of Foodborne Pathogens in Natural Cheeses in Japan

    Directory of Open Access Journals (Sweden)

    Firew Kassa Esho

    2013-01-01

    Full Text Available The production and consumption of domestic natural cheese in Japan is increasing year by year. More than ninety percent of domestic natural cheese is produced in Hokkaido region of Japan, while information on its quality and safety related to foodborne pathogens is limited. To assess the microbiological safety of domestic natural cheese, a total of 126 natural cheese samples produced in Hokkaido were collected from December, 2012, to July, 2013. In addition to standard plate count (SPC and coliform counts, the prevalence study of three pathogens (Listeria monocytogenes, pathogenic Escherichia coli, and Salmonella spp. was performed on each sample. Real-time PCR and matrix-assisted laser desorption-ionization time-of-flight mass spectrometer methods were employed for identification of presumptive pathogens. Coliform was detected in 25 samples (19.8% with a minimum of 25 cfu/g and a maximum of more than 3.0 × 106 cfu/g. Salmonella spp. and L. monocytogenes were not isolated from any of the samples. Only one sample (0.80% showed positive PCR amplification for ipaH gene suggesting possible contamination of enteroinvasive E. coli or Shigella in this product. Overall results indicate that natural cheeses produced in Hokkaido region were satisfactory microbiological quality according to existing international standards.

  10. Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa

    Directory of Open Access Journals (Sweden)

    Mokaba Shirley Malema

    2018-05-01

    Full Text Available Although many developing countries use harvested rainwater (HRW for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert®18/Quanti-Tray® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR, and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC (ibeA 28% while pathotype enteroaggregative E. coli (EAEC was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%. All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR. The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli.

  11. Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa.

    Science.gov (United States)

    Malema, Mokaba Shirley; Abia, Akebe Luther King; Tandlich, Roman; Zuma, Bonga; Mwenge Kahinda, Jean-Marc; Ubomba-Jaswa, Eunice

    2018-05-01

    Although many developing countries use harvested rainwater (HRW) for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert ® 18/Quanti-Tray ® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR), and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) ( ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli.

  12. DMPD: Toll-like receptors and the host defense against microbial pathogens: bringingspecificity to the innate-immune system. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15075354 Toll-like receptors and the host defense against microbial pathogens: brin...oc Biol. 2004 May;75(5):749-55. Epub 2004 Jan 14. (.png) (.svg) (.html) (.csml) Show Toll-like receptors and the host defense again...immune system. PubmedID 15075354 Title Toll-like receptors and the host defense against microbial pathogens:

  13. Antigenic Relationships among Human Pathogenic Orientia tsutsugamushi Isolates from Thailand.

    Directory of Open Access Journals (Sweden)

    Sarah L James

    2016-06-01

    Full Text Available Scrub typhus is a common cause of undiagnosed febrile illness in certain tropical regions, but can be easily treated with antibiotics. The causative agent, Orientia tsutsugamushi, is antigenically variable which complicates diagnosis and efforts towards vaccine development.This study aimed to dissect the antigenic and genetic relatedness of O. tsutsugamushi strains and investigate sero-diagnostic reactivities by titrating individual patient sera against their O. tsutsugamushi isolates (whole-cell antigen preparation, in homologous and heterologous serum-isolate pairs from the same endemic region in NE Thailand. The indirect immunofluorescence assay was used to titrate Orientia tsutsugamushi isolates and human sera, and a mathematical technique, antigenic cartography, was applied to these data to visualise the antigenic differences and cross-reactivity between strains and sera. No functional or antigen-specific analyses were performed. The antigenic variation found in clinical isolates was much less pronounced than the genetic differences found in the 56kDa type-specific antigen genes. The Karp-like sera were more broadly reactive than the Gilliam-like sera.Antigenic cartography worked well with scrub typhus indirect immunofluorescence titres. The data from humoral responses suggest that a Karp-like strain would provide broader antibody cross-reactivity than a Gilliam-like strain. Although previous exposure to O. tsutsugamushi could not be ruled out, scrub typhus patient serum antibody responses were characterised by strong homologous, but weak heterologous antibody titres, with little evidence for cross-reactivity by Gilliam-like sera, but a broader response from some Karp-like sera. This work highlights the importance of antigenic variation in O. tsutsugamushi diagnosis and determination of new serotypes.

  14. Antimicrobial activity of ceftaroline and other anti-infective agents against microbial pathogens recovered from the surgical intensive care patient population: a prevalence analysis.

    Science.gov (United States)

    Edmiston, Charles E; Krepel, Candace J; Leaper, David; Ledeboer, Nathan A; Mackey, Tami-Lea; Graham, Mary Beth; Lee, Cheong; Rossi, Peter J; Brown, Kellie R; Lewis, Brian D; Seabrook, Gary R

    2014-12-01

    Ceftaroline is a new parenteral cephalosporin agent with excellent activity against methicillin-sensitive (MSSA) and resistant strains of Staphylococcus aureus (MRSA). Critically ill surgical patients are susceptible to infection, often by multi-drug-resistant pathogens. The activity of ceftaroline against such pathogens has not been described. Three hundred thirty-five consecutive microbial isolates were collected from surgical wounds or abscesses, respiratory, urine, and blood cultures from patients in the surgical intensive care unit (SICU) of a major tertiary medical center. Using Clinical and Laboratory Standards Institute (CLSI) standard methodology and published breakpoints, all aerobic, facultative anaerobic isolates were tested against ceftaroline and selected comparative antimicrobial agents. All staphylococcal isolates were susceptible to ceftaroline at a breakpoint of ≤1.0 mcg/mL. In addition, ceftaroline exhibited excellent activity against all streptococcal clinical isolates and non-ESBL-producing strains of Enterobacteriaceae (93.5%) recovered from SICU patients. Ceftaroline was inactive against ESBL-producing Enterobacteriaceae, Pseudomonas aeruginosa, vancomycin-resistant enterococci, and selective gram-negative anaerobic bacteria. At present, ceftaroline is the only cephalosporin agent that is active against community and healthcare-associated MRSA. Further studies are needed to validate the benefit of this novel broad-spectrum anti-infective agent for the treatment of susceptible serious infections in the SICU patient population.

  15. Occurrence and antibacterial susceptibility pattern of bacterial pathogens isolated from diarrheal patients in Pakistan

    OpenAIRE

    Rasool, Muhammad H.; Siddique, Abu B.; Saqalein, Muhammad; Asghar, Muhammad J.; Zahoor, Muhammad A.; Aslam, Bilal; Shafiq, Humerah B.; Nisar, Muhammad A.

    2016-01-01

    Objective: To determine the occurrence of bacterial pathogens responsible for diarrhea and to engender information regarding the effectiveness of commonly used antibiotic against diarrhea. Methods: This cross-sectional study was conducted between April and July 2014. Samples were collected from the Divisional Headquarter and Allied Hospital, Faisalabad, Pakistan. The differential and selective media were used to isolate bacterial pathogens, which were identified through cultural character...

  16. Enrichment and isolation of microbial strains degrading bioplastic ...

    African Journals Online (AJOL)

    acer

    2015-07-08

    Jul 8, 2015 ... The sea sediments and sea water samples were collected from sites highly polluted with plastic waste from one of the beaches of Mumbai, India. Polymer sample. PVA (M.W. 125000) in powdered form was purchased from S. D.. Fine Chemicals, Mumbai, India. Enrichment of PVA degrading microbial stains.

  17. TLR-dependent human mucosal epithelial cell responses to microbial pathogens.

    Directory of Open Access Journals (Sweden)

    Paola eMassari

    2014-08-01

    Full Text Available AbstractToll-Like Receptor (TLR signaling represents one of the best studied pathways to implement defense mechanisms against invading microbes in humans as well as in animals. TLRs respond to specific microbial ligands and to danger signals produced by the host during infection, and initiate downstream cascades that activate both innate and adaptive immunity. TLRs are expressed by professional immune cells and by the large majority of non-hematopoietic cells, including epithelial cells. In epithelial tissues, TLR functions are particularly important because these sites are constantly exposed to microorganisms, due to their location at the host interface with the environment. While at these sites, specific defense mechanisms and inflammatory responses are initiated via TLR signaling against pathogens, suppression or lack of TLR activation is also observed in response to the commensal microbiota. The mechanisms by which TLR signaling is regulated in mucosal epithelial cells include differential expression and levels of TLRs (and their signaling partners, their cellular localization and positioning within the tissue in a fashion that favors responses to pathogens while dampening responses to commensals and maintaining tissue homeostasis in physiologic conditions. In this review, the expression and activation of TLRs in mucosal epithelial cells of several sites of the human body are examined. Specifically, the oral cavity, the ear canal and eye, the airways, the gut and the reproductive tract are discussed, along with how site-specific host defense mechanisms are implemented via TLR signaling.

  18. Assessment and impact of microbial fecal pollution and human enteric pathogens in a coastal community.

    Science.gov (United States)

    Lipp, E K; Farrah, S A; Rose, J B

    2001-04-01

    The goals of this study were to assess watersheds impacted by high densities of OSDS (onsite sewage disposal systems) for evidence of fecal contamination and evaluate the occurrence of human pathogens in coastal waters off west Florida. Eleven stations (representing six watersheds) were intensively sampled for microbial indicators of fecal pollution (fecal coliform bacteria, enterococci, Clostridium perfringens and coliphage) and the human enteric pathogens, Cryptosporidium, Giardia, and enteroviruses during the summer rainy season (May-September 1996). Levels of all indicators ranged between 4000 CFU/100 ml. Cryptosporidium and Giardia were detected infrequently (6.8% and 2.3% of samples tested positive, respectively). Conversely, infectious enteroviruses were detected at low levels in 5 of the 6 watersheds sampled. Using cluster analysis, sites were grouped into two categories, high and low risks, based on combined levels of indicators. These results suggest that stations of highest pollution risk were located within areas of high OSDS densities. Furthermore, data indicate a subsurface transport of contaminated water to surface waters. The high prevalence of enteroviruses throughout the study area suggests a chronic pollution problem and potential risk to recreational swimmers in and around Sarasota Bay.

  19. Evaluation of Pathogen Removal in a Solar Sludge Drying Facility Using Microbial Indicators

    Directory of Open Access Journals (Sweden)

    D. İpek Kurtböke

    2010-02-01

    Full Text Available South East Queensland is one of the fastest growing regions in Australia with a correspondingly rapid increase in sewage production. In response, local councils are investing in more effective and sustainable options for the treatment and reuse of domestic and industrial effluents. A novel, evaporative solar dryer system has been installed on the Sunshine Coast to convert sewage sludge into a drier, usable form of biosolids through solar radiation exposure resulting in decreased moisture concentration and pathogen reduction. Solar-dried biosolids were analyzed for selected pathogenic microbial, metal and organic contaminants at the end of different drying cycles in a collaborative study conducted with the Regional Council. Although fecal coliforms were found to be present, enteroviruses, parasites, E. coli, and Salmonella sp. were not detected in the final product. However, elevated levels of zinc and copper were still present which restricted public use of the biosolids. Dilution of the dried biosolids with green waste as well as composting of the biosolids is likely to lead to the production of an environmentally safe, Class A end-product.

  20. Isolation, pathogenicity and characterization of a novel bacterial pathogen Streptococcus uberis from diseased mandarin fish Siniperca chuatsi.

    Science.gov (United States)

    Luo, Xia; Fu, Xiaozhe; Liao, Guoli; Chang, Ouqin; Huang, Zhibin; Li, Ningqiu

    2017-06-01

    In recent years, mandarin fish had a high mortality rate associated with abnormal swimming, exophthalmia, corneal opacity and eye hemorrhage on a fish farm located at Foshan city, Guangdong province, China. Three isolates of Gram-positive, chain-forming cocci were recovered from moribund fish, and designated as SS131025-1, SS131025-2, and SS131025-3. These isolates were identified as Streptococcus uberis according to their morphologic and physio-biochemical characteristics as well as phylogenetic analysis based on their 16S rRNA and GapC gene sequences. The pathogenicity of S. uberis to mandarin fish was determined by challenge experiments. Results of artificial challenge showed S. uberis infected healthy mandarin fish and lead to death by eyeball injection or immersion route, and the LD 50 of SS131025-1 with eyeball injection was 2.0 × 10 6.42  CFU per fish. Moreover extracellular product (ECP) of the isolated S.uberis induced CPB cell apoptosis and cause death of mandarin fish. In addition, these S. uberis strains could also infect tilapia, but not grass carp and crucian carp, and grew in brain-heart infusion broth with an optimal temperature of 37 °C, pH of 7.0, and salinity of 0%. Antibiotic sensitivity testing indicated that these isolates were susceptible to rifampicin and furazolidone but resistant to 20 kinds of antibiotics. Histopathologically, infection with S. uberis could cause serious pathological changes in brain tissues such as vacuoles in matrix, swollen mitochondria with lysis of cristae and disintegration, and lots of coccus was observed both under electron and light microscope. These results shed some light on the pathogenicity of the isolates and how to prevent and control S. uberis infection in mandarin fish. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Entomopathogens Isolated from Invasive Ants and Tests of Their Pathogenicity

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Miori de Zarzuela

    2012-01-01

    Full Text Available Some ant species cause severe ecological and health impact in urban areas. Many attempts have been tested to control such species, although they do not always succeed. Biological control is an alternative to chemical control and has gained great prominence in research, and fungi and nematodes are among the successful organisms controlling insects. This study aimed to clarify some questions regarding the biological control of ants. Invasive ant species in Brazil had their nests evaluated for the presence of entomopathogens. Isolated entomopathogens were later applied in colonies of Monomorium floricola under laboratory conditions to evaluate their effectiveness and the behavior of the ant colonies after treatment. The entomopathogenic nematodes Heterorhabditis sp. and Steinernema sp. and the fungi Beauveria bassiana, Metarhizium anisopliae, and Paecilomyces sp. were isolated from the invasive ant nests. M. floricola colonies treated with Steinernema sp. and Heterorhabditis sp. showed a higher mortality of workers than control. The fungus Beauveria bassiana caused higher mortality of M. floricola workers. However, no colony reduction or elimination was observed in any treatment. The defensive behaviors of ants, such as grooming behavior and colony budding, must be considered when using fungi and nematodes for biological control of ants.

  2. Peracetic Acid (PAA Disinfection: Inactivation of Microbial Indicators and Pathogenic Bacteria in a Municipal Wastewater Plant

    Directory of Open Access Journals (Sweden)

    Silvia Bonetta

    2017-06-01

    Full Text Available Several studies have noted that treated and untreated wastewaters are primary contributors of a variety of pathogenic microorganisms to the aquatic ecosystem. Conventional wastewater treatment may not be sufficient to achieve microbiologically safe effluent to be discharged into natural waters or reused, thus requiring wastewater effluents to be disinfected. In recent years, peracetic acid (PAA has been adopted as a disinfectant for wastewater effluents. The aim of this study was to evaluate the disinfection efficiency of PAA at low doses (range 0.99–2.10 mg/L against microbial indicators and pathogenic bacteria in a municipal wastewater plant. Samples of untreated sewage and effluents before and after PAA treatment were collected seasonally for 1 year and were analysed for pathogenic Campylobacter, Salmonella spp., E. coli O157:H7 and E. coli virulence genes using molecular methods; moreover, the detection of specific microbial indicators (E. coli, faecal coliforms, enterococci, C. perfringens and Salmonella spp. were carried out using culturing methods. Salmonella spp. DNA was found in all untreated sewage and effluent before PAA treatment, whereas it was recovered in 50% of the samples collected after PAA treatment. Although E. coli O157:H7 was never identified, the occurrence of Shiga-like toxin I amplicons was identified in 75% of the untreated sewage samples, in 50% of the effluents assayed before PAA treatment, and in 25% of the effluents assayed after PAA treatment, whereas the stx2 gene was never found. Campylobacter coli was only detected in one effluent sample before PAA treatment. In the effluents after PAA treatment, a lower load of indicator bacteria was observed compared to the effluents before treatment. The results of this study highlight that the use of low doses of PAA seems to lead to an improvement of the microbiological quality of the effluent, although it is not sufficient to guarantee its suitability for irrigation

  3. Isolate-dependent growth, virulence, and cell wall composition in the human pathogen Aspergillus fumigatus.

    Directory of Open Access Journals (Sweden)

    Nansalmaa Amarsaikhan

    Full Text Available The ubiquitous fungal pathogen Aspergillus fumigatus is a mediator of allergic sensitization and invasive disease in susceptible individuals. The significant genetic and phenotypic variability between and among clinical and environmental isolates are important considerations in host-pathogen studies of A. fumigatus-mediated disease. We observed decreased radial growth, rate of germination, and ability to establish colony growth in a single environmental isolate of A. fumigatus, Af5517, when compared to other clinical and environmental isolates. Af5517 also exhibited increased hyphal diameter and cell wall β-glucan and chitin content, with chitin most significantly increased. Morbidity, mortality, lung fungal burden, and tissue pathology were decreased in neutropenic Af5517-infected mice when compared to the clinical isolate Af293. Our results support previous findings that suggest a correlation between in vitro growth rates and in vivo virulence, and we propose that changes in cell wall composition may contribute to this phenotype.

  4. Microbial isolates in open fractures seen in the accident and ...

    African Journals Online (AJOL)

    Routine microscopy, culture and sensitivities for aerobic and anaerobic organisms were carried out on these specimens. ... pattern of all the isolates shows that pefloxacin, ciprofloxacin and ceftriaxone were more effective compared to cefuroxime and amoxycillin which had substantial resistance to most of the isolates.

  5. Draft genome sequences of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from human patients

    OpenAIRE

    Mendoza-Olazar?n, Soraya; Garcia-Mazcorro, Jos? F.; Morf?n-Otero, Rayo; Villarreal-Trevi?o, Licet; Camacho-Ortiz, Adri?n; Rodr?guez-Noriega, Eduardo; Bocanegra-Ibarias, Paola; Maldonado-Garza, H?ctor J.; Dowd, Scot E.; Garza-Gonz?lez, Elvira

    2017-01-01

    Herein, we report the draft-genome sequences and annotation of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from humans. One strain (SC-57) was isolated from blood from a male patient in May 2006 and the other (SC-532) from a catheter from a male patient in June 2006. Similar to other genomes of Staphylococcus species, most genes (42%) of both strains are involved in metabolism of amino acids and derivatives, carbohydrates and proteins. Eighty (4%) genes are involved...

  6. Prevalence of plant beneficial and human pathogenic bacteria isolated from salad vegetables in India.

    Science.gov (United States)

    Nithya, Angamuthu; Babu, Subramanian

    2017-03-14

    The study aimed at enumerating, identifying and categorizing the endophytic cultivable bacterial community in selected salad vegetables (carrot, cucumber, tomato and onion). Vegetable samples were collected from markets of two vegetable hot spot growing areas, during two different crop harvest seasons. Crude and diluted vegetable extracts were plated and the population of endophytic bacteria was assessed based on morphologically distinguishable colonies. The bacterial isolates were identified by growth in selective media, biochemical tests and 16S rRNA gene sequencing. The endophytic population was found to be comparably higher in cucumber and tomato in both of the sampling locations, whereas lower in carrot and onion. Bacterial isolates belonged to 5 classes covering 46 distinct species belonging to 19 genera. Human opportunistic pathogens were predominant in carrot and onion, whereas plant beneficial bacteria dominated in cucumber and tomato. Out of the 104 isolates, 16.25% are human pathogens and 26.5% are human opportunistic pathogens. Existence of a high population of plant beneficial bacteria was found to have suppressed the population of plant and human pathogens. There is a greater potential to study the native endophytic plant beneficial bacteria for developing them as biocontrol agents against human pathogens that are harboured by plants.

  7. Track-Etched Magnetic Micropores for Immunomagnetic Isolation of Pathogens

    Science.gov (United States)

    Muluneh, Melaku; Shang, Wu

    2014-01-01

    A microfluidic chip is developed to selectively isolate magnetically tagged cells from heterogeneous suspensions, the track-etched magnetic micropore (TEMPO) filter. The TEMPO consists of an ion track-etched polycarbonate membrane coated with soft magnetic film (Ni20Fe80). In the presence of an applied field, provided by a small external magnet, the filter becomes magnetized and strong magnetic traps are created along the edges of the micropores. In contrast to conventional microfluidics, fluid flows vertically through the porous membrane allowing large flow rates while keeping the capture rate high and the chip compact. By utilizing track-etching instead of conventional semiconductor fabrication, TEMPOs can be fabricated with microscale pores over large areas A > 1 cm2 at little cost ( 500 at a flow rate of Φ = 5 mL h−1. Furthermore, the large density of micropores (ρ = 106 cm−2) allows the TEMPO to sort E. coli from unprocessed environmental and clinical samples, as the blockage of a few pores does not significantly change the behavior of the device. PMID:24535921

  8. Pseudomonas floridensis sp. nov., a bacterial pathogen isolated from tomato.

    Science.gov (United States)

    Timilsina, Sujan; Minsavage, Gerald V; Preston, James; Newberry, Eric A; Paret, Matthews L; Goss, Erica M; Jones, Jeffrey B; Vallad, Gary E

    2018-01-01

    An unusual fluorescent pseudomonad was isolated from tomato exhibiting leaf spot symptoms similar to bacterial speck. Strains were fluorescent, oxidase- and arginine-dihydrolase-negative, elicited a hypersensitive reaction on tobacco and produced a soft rot on potato slices. However, the strains produced an unusual yellow, mucoid growth on media containing 5 % sucrose that is not typical of levan. Based on multilocus sequence analysis using 16S rRNA, gap1, gltA, gyrB and rpoD, these strains formed a distinct phylogenetic group in the genus Pseudomonas and were most closely related to Pseudomonas viridiflava within the Pseudomonassyringae complex. Whole-genome comparisons, using average nucleotide identity based on blast, of representative strain GEV388 T and publicly available genomes representing the genus Pseudomonas revealed phylogroup 7 P. viridiflava strain UASW0038 and P. viridiflava type strain ICMP 2848 T as the closest relatives with 86.59 and 86.56 % nucleotide identity, respectively. In silico DNA-DNA hybridization using the genome-to-genome distance calculation method estimated 31.1 % DNA relatedness between GEV388 T and P. viridiflava ATCC 13223 T , strongly suggesting the strains are representatives of different species. These results together with Biolog GEN III tests, fatty acid methyl ester profiles and phylogenetic analysis using 16S rRNA and multiple housekeeping gene sequences demonstrated that this group represents a novel species member of the genus Pseudomonas. The name Pseudomonas floridensis sp. nov. is proposed with GEV388 T (=LMG 30013 T =ATCC TSD-90 T ) as the type strain.

  9. Molecular identification and pathogenicity of Citrobacter and Serratia species isolated from cultured Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Manal I. El-Barbary

    2017-09-01

    Full Text Available This study aimed to isolate and characterize some pathogenic bacterial strains belonging to the family Enterobacteriaceae. They had been isolated from gills, liver, kidney and skin of naturally infected Oreochromis niloticus and had been identified by biochemical test and 16S rRNA gene using four universal primers. Additionally, the isolates were tested for antimicrobial susceptibility, histopathological alterations of liver, kidney and gills and the pathogenicity of the identified isolates for O. niloticus. The results of phylogenetic analysis placed the isolates in the family Enterobacteriaceae (genera Serratia and Citrobacter based on 99% homology. The primer pair (17F and 1390R is the most appropriate pair of universal primers employed for the identification of 16S rRNA gene as it covers as much as possible of the variable regions (Vs. V1 and V2 regions of 16S rRNA gene presented weak evidence of the diversity of the genera Serratia. The mortality rate was 40–60% after challenging O. niloticus by identified isolates, which revealed its sensitivity to ciprofloxacin and norfloxacin. Histological changes showed dilation in sinusoids with severe vacuolar degeneration in the liver, tubular degeneration and hemorrhage between renal tubules with pyknotic nuclei in the kidney, epithelial hyperplasia, aneurism and evident epithelium interstitial edema in gills of O. niloticus. This study concluded that these isolates should be considered as an opportunistic pathogen of O. niloticus. The study also states that the sequencing of 16S rRNA is an important tool for the identification of unknown bacterial species of fish pathogen. Keywords: Citrobacter sp., Serratia sp., Phylogenetic analysis, Histology, Antibiotic sensitivity, Oreochromis niloticus

  10. Occurrence and antibacterial susceptibility pattern of bacterial pathogens isolated from diarrheal patients in Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad H. Rasool

    2016-03-01

    Full Text Available Objective: To determine the occurrence of bacterial pathogens responsible for diarrhea and to engender information regarding the effectiveness of commonly used antibiotic against diarrhea. Methods: This cross-sectional study was conducted between April and July 2014. Samples were collected from the Divisional Headquarter and Allied Hospital, Faisalabad, Pakistan. The differential and selective media were used to isolate bacterial pathogens, which were identified through cultural characteristics, microscopy, and biochemical tests. Disc diffusion assay was carried out using Muller Hinton agar medium, and minimum inhibitory concentration was determined using broth dilution method against isolated pathogens. Results: One hundred and forty-one (100% samples were positive for some bacteria. Frequency of occurrence was Bacillus cereus (B. cereus (66%, Escherichia coli (E. coli (48.5%, Salmonella typhi (S. Typhi (27.7%, Pseudomonas aeruginosa (P. aeruginosa (8.5%, and Staphylococcus aureus (S. aureus (4.3%. Single pathogen was detected in 20 (14.2% samples whereas combinations were found in 121 (85.8% samples. Bacillus cereus and E. coli were the most frequently detected pathogens followed by the S. Typhi, P. aeruginosa, and Staph. aureus. The percentage occurrence of isolated pathogens was 31% in B. cereus, 31% in E. coli, 18% in S. Typhi, 5% in P. aeruginosa, and 3% in Staph. aureus. Conclusion: Pseudomonas aeruginosa showed resistance against Amoxicillin and Cefotaxime, whereas S. aureus was found resistant against Cefotaxime. Statistical analysis using one way Analysis of Variance revealed that Ofloxacin and Gentamicin had significant (p<0.05 differences against all isolates as compared with other antibiotics used in this study.

  11. TAXONOMY OF FUSARIUM SPECIES ISOLATED FROM CULTIVATED PLANTS, WEEDS AND THEIR PATHOGENICITY FOR WHEAT

    Directory of Open Access Journals (Sweden)

    Jasenka Ćosić

    2002-06-01

    Full Text Available Fusarium species are wide-spread and known to be pathogenic agents to cultivated plants in various agroclimatic areas. During a four year investigation 10 Fusarium species and Microdochium nivale were isolated from wheat, barley, maize and soybean as well as from 10 weeds collected from 10 locations in Slavonia and Baranya. Fusarium graminearum was dominant on wheat and barley, F. moniliforme on maize and F. oxysporum on soybean. Regarding weeds, the presence of the following Fusarium species was established: F. graminearum on Amaranthus hybridus, Capsella bursa-pastoris, Lamium purpureum, Sorghum halepense and Urtica dioica, F. moniliforme on Abutilon theophrasti, F. subglutinans on Polygonum aviculare, F. avenaceum on Capsella bursa-pastoris, Rumex crispus and Matricaria sp., F. culmorum on Abutilon theophrasti, F. sporotrichioides on Polygonum aviculare, F. proliferatum and F. poae on Artemisia vulgaris. Pathogenicity test to wheat seedlings was done in our laboratory on winter wheat cultivars Slavonija and Demetra (totally 146 isolates. The most pathogenic species to wheat seedilings were F. graminearum, F. culmorum and F. sporotrichioides and the least pathogenic F. moniliforme, F. solani, F. oxysporum and F. poae. Pathogenicity test for wheat ears was done on genotypes Osk.8c9/3-94 and Osk.6.11/2 (totally 25 isolates. The results obtained by our investigation showed that there were no significant differences in pathogenicity of Fusarium species isolated from both cultivated plants and weeds. Weeds represent a constant source of inoculum of F. species for cultivated plants and they serve as epidemiologic bridges among vegetations.

  12. Occurrence and antibacterial susceptibility pattern of bacterial pathogens isolated from diarrheal patients in Pakistan.

    Science.gov (United States)

    Rasool, Muhammad H; Siddique, Abu B; Saqalein, Muhammad; Asghar, Muhammad J; Zahoor, Muhammad A; Aslam, Bilal; Shafiq, Humerah B; Nisar, Muhammad A

    2016-03-01

    To determine the occurrence of bacterial pathogens responsible for diarrhea and to engender information regarding the effectiveness of commonly used antibiotic against diarrhea. This cross-sectional study was conducted between April and July 2014. Samples were collected from the Divisional Headquarter and Allied Hospital, Faisalabad, Pakistan. The differential and selective media were used to isolate bacterial pathogens, which were identified through cultural characteristics, microscopy, and biochemical tests. Disc diffusion assay was carried out using Muller Hinton agar medium, and minimum inhibitory concentration was determined using broth dilution method against isolated pathogens. One hundred and forty-one (100%) samples were positive for some bacteria. Frequency of occurrence was Bacillus cereus (B. cereus) (66%), Escherichia coli (E.coli) (48.5%), Salmonella typhi (S. Typhi) (27.7%), Pseudomonas aeruginosa (P. aeruginosa) (8.5%), and Staphylococcus aureus (S. aureus) (4.3%). Single pathogen was detected in 20 (14.2%) samples whereas combinations were found in 121 (85.8%) samples. Bacillus cereus and E.coli were the most frequently detected pathogens followed by the S. Typhi, P. aeruginosa, and Staph. aureus. The percentage occurrence of isolated pathogens was 31% in B. cereus, 31% in E. coli, 18% in S. Typhi, 5% in P. aeruginosa, and 3% in Staph. aureus. Pseudomonas aeruginosa showed resistance against Amoxicillin and Cefotaxime, whereas S. aureus was found resistant against Cefotaxime. Statistical analysis using one way Analysis of Variance revealed that Ofloxacin and Gentamicin had significant (p less than 0.05) differences against all isolates as compared with other antibiotics used in this study.

  13. Linking social and pathogen transmission networks using microbial genetics in giraffe (Giraffa camelopardalis).

    Science.gov (United States)

    VanderWaal, Kimberly L; Atwill, Edward R; Isbell, Lynne A; McCowan, Brenda

    2014-03-01

    Although network analysis has drawn considerable attention as a promising tool for disease ecology, empirical research has been hindered by limitations in detecting the occurrence of pathogen transmission (who transmitted to whom) within social networks. Using a novel approach, we utilize the genetics of a diverse microbe, Escherichia coli, to infer where direct or indirect transmission has occurred and use these data to construct transmission networks for a wild giraffe population (Giraffe camelopardalis). Individuals were considered to be a part of the same transmission chain and were interlinked in the transmission network if they shared genetic subtypes of E. coli. By using microbial genetics to quantify who transmits to whom independently from the behavioural data on who is in contact with whom, we were able to directly investigate how the structure of contact networks influences the structure of the transmission network. To distinguish between the effects of social and environmental contact on transmission dynamics, the transmission network was compared with two separate contact networks defined from the behavioural data: a social network based on association patterns, and a spatial network based on patterns of home-range overlap among individuals. We found that links in the transmission network were more likely to occur between individuals that were strongly linked in the social network. Furthermore, individuals that had more numerous connections or that occupied 'bottleneck' positions in the social network tended to occupy similar positions in the transmission network. No similar correlations were observed between the spatial and transmission networks. This indicates that an individual's social network position is predictive of transmission network position, which has implications for identifying individuals that function as super-spreaders or transmission bottlenecks in the population. These results emphasize the importance of association patterns in

  14. Middle East Desert Dust Exposure: Health Risks from Metals and Microbial Pathogens

    Science.gov (United States)

    Lyles, M. B.

    2014-12-01

    In the Middle East, dust and sand storms are a persistent problem and can deliver significant amounts of micro-particulates via inhalation into the mouth, nasal pharynx, & lungs due to the fine size and abundance of these micro-particulates. The chronic and acute health risks of this dust inhalation have not been well studied nor has the dust been effectively characterized as to its chemical composition, mineral content, or microbial flora. Scientific experiments were designed to study the Kuwaiti and Iraqi dust as to its physical, chemical, and biological characteristics and for its potential to cause adverse health effects. First, dust samples from different locations were collected and processed and exposure data collected. Initial chemical and physical characterization of each sample including particle size distribution and inorganic analysis was conducted, followed by characterization of biologic flora of the dust, including bacteria, fungi and viruses. Data indicates that the mineralized dust is composed of calcium carbonate over a matrix of metallic silicate nanocrystals containing a variety of trace and heavy metals constituting ~3 % of the PM10 particles by weight, of which ~1% is bioaccessible aluminum and reactive iron, each. The particles also consist of ~1% bioavailable aluminum and reactive iron each. Microbial analysis reveals a significant biodiversity of bacterial, fungi, and viruses of which ~30% are known pathogens. Of the microbes identified, several have hemolytic properties and most have significant antibiotic resistance. Viral analysis indicates a tremendous amount of virons with a large percent of RNA viruses. The level of total suspended particle mass at PM 10 along with environmental & physiological conditions present constitute an excessive exposure to micro-particulates including PM 2.5 and the potential for adverse health effects. Reported data on cell culture and animal studies have indicated a high level of toxicity to these dust

  15. Virulence gene profiles of avian pathogenic Escherichia coli isolated from chickens with colibacillosis in Bulawayo, Zimbabwe

    Directory of Open Access Journals (Sweden)

    Joshua Mbanga

    2015-04-01

    Full Text Available Colibacillosis, a disease caused by avian pathogenic Escherichia coli (APEC, is one of the main causes of economic losses in the poultry industry worldwide. This study was carried out in order to determine the APEC-associated virulence genes contained by E. coli isolates causing colibacillosis in chickens. A total of 45 E. coli isolates were obtained from the diagnostics and research branch of the Central Veterinary Laboratories, Bulawayo, Zimbabwe. These isolates were obtained from chickens with confirmed cases of colibacillosis after postmortem examination. The presence of the iutA, hlyF, ompT, frz, sitD, fimH, kpsM, sitA, sopB, uvrY, pstB and vat genes were investigated by multiplex polymerase chain reaction (PCR assay. Of the 45 isolates, 93% were positive for the presence of at least one virulence gene. The three most prevalent virulence genes were iutA (80%, fimH (33.3% and hlyF (24.4%. The kpsM, pstB and ompT genes had the lowest prevalence, having been detected in only 2.2% of the isolates. All 12 virulence genes studied were detected in the 45 APEC isolates. Virulence gene profiles were constructed for each APEC isolate from the multiplex data. The APEC isolates were profiled as 62.2% fitting profile A, 31.1% profile B and 6.7% profile C. None of the isolates had more than seven virulence genes. Virulence profiles of Zimbabwean APEC isolates are different from those previously reported. Zimbabwean APEC isolates appear to be less pathogenic and may rely on environmental factors and stress in hosts to establish infection.

  16. Pathogenicity and molecular analysis of an infectious bursal disease virus isolated from Malaysian village chickens.

    Science.gov (United States)

    Tan, D Y; Hair-Bejo, M; Omar, A R; Aini, I

    2004-01-01

    The characteristics of the pathogenic infectious bursal disease virus (IBDV) that infected avian species other than commercial chickens were largely unknown. In this study, by using in vivo and molecular methods, we had characterized an IBDV isolate (named 94268) isolated from an infectious bursal disease (IBD) outbreak in Malaysian village chickens--the adulterated descendant of the Southeast Asian jungle fowl (Gallus bankiva) that were commonly reared in the backyard. The 94268 isolate was grouped as the very virulent IBDV (vvIBDV) strain because it caused severe lesions and a high mortality rate in village chickens (>88%) and experimentally infected specific-pathogen-free chickens (>66%). In addition, it possessed all of the vvIBDV molecular markers in its VP2 gene. Phylogenetic analysis using distance, maximum parsimony, and maximum likelihood methods revealed that 94268 was monophyletic with other vvIBDV isolates and closely related to the Malaysian vvIBDV isolates. Given that the VP2 gene of 94268 isolate was almost identical and evolutionarily closely related to other field IBDV isolates that affected the commercial chickens, we therefore concluded that IBD infections had spread across the farm boundary. IBD infection in the village chicken may represent an important part of the IBD epidemiology because these birds could harbor the vvIBDV strain and should not be overlooked in the control and prevention of the disease.

  17. Biocontrol efficacy of different isolates of Trichoderma against soil borne pathogen Rhizoctonia solani.

    Science.gov (United States)

    Asad, Saeed Ahmad; Ali, Naeem; Hameed, Abdul; Khan, Sabaz Ali; Ahmad, Rafiq; Bilal, Muhammad; Shahzad, Muhammad; Tabassum, Ayesha

    2014-01-01

    In this study, the biocontrol abilities of water-soluble and volatile metabolites of three different isolates of Trichoderma (T. asperellum, T. harzianum and Trichoderma spp.) against soil borne plant pathogen Rhizoctonia solani were investigated both in vitro and in vivo. The results showed for the first time that mycelial growth inhibition of the pathogen was 74.4-67.8% with water-soluble metabolites as compared to 15.3-10.6% with volatile metabolites in vitro. In vivo antagonistic activity of Trichoderma isolates against R. solani was evaluated on bean plants under laboratory and greenhouse conditions. We observed that T. asperellum was more effective and consistent, lowering disease incidence up to 19.3% in laboratory and 30.5% in green house conditions. These results showed that three isolates of Trichoderma could be used as effective biocontrol agents against R. solani.

  18. Morphological and Pathogenic Variability among Macrophomina phaseolina Isolates Associated with Mungbean (Vigna radiata L. Wilczek from Pakistan

    Directory of Open Access Journals (Sweden)

    Umer Iqbal

    2014-01-01

    Full Text Available Macrophomina phaseolina is a serious pathogen of many crops. In the present studies, 65 isolates of Macrophomina phaseolina from different agroecological regions of Punjab and Khyber Pakhtunkhwa provinces of Pakistan were analyzed for morphological and pathogenic variability. Regardless of their geographic origins, significant differences were detected among 65 isolates in their radial growth, sclerotial size, and weight as well as in pathogenicity. Sixteen isolates were rated as fast growing, 11 as slow growing, and the rest of the isolates as medium growing. Nine isolates were classified as large sized, 26 as small sized, and the remaining 30 isolates as medium sized. Thirty five isolates were ranked as heavy weight, 12 as low weight, and the rest of isolates were grouped as medium weight. Ten fungal isolates appeared to be least virulent, whereas eight isolates of diverse origin proved to be highly virulent against mungbean cultivars. The remaining isolates were regarded as moderately virulent. No relationship was found among the morphological characters and pathogenicity of the isolates. These morphological and pathogenic variations in various isolates of M. phaseolina may be considered important in disease management systems and will be useful in breeding programmes of mungbean cultivars resistant to charcoal rot.

  19. Presence of pathogenicity island genes in Enterococcus faecalis isolates from pigs in Denmark

    DEFF Research Database (Denmark)

    Shankar, Nathan; Baghdayan, Arto S.; Willems, Rob

    2006-01-01

    Enterococcus faecalis isolates of porcine origin were screened for the presence of a previously identified pathogenicity island (PAI). By using the esp gene as a genetic marker for the presence of this PAI, 9 esp-positive and 10 esp-negative isolates of porcine origin were investigated by use...... of a designed oligonucleotide array. The results indicated the clustering of esp-positive strains by multilocus sequence typing (MLST), but surprisingly, all strains investigated contained parts of the PAL None of the strains of animal origin investigated belonged to previously identified MLST complex 2, where...... most isolates from patients cluster. Five of the nine esp-positive E. faecalis isolates of animal origin belonged to the same PAI complex as human isolate MMH594 but differed in their sequence types, which strongly indicates the horizontal transfer of the PAI between enterococci of porcine and human...

  20. Ultrastructural investigation on radiation resistant microbial isolates of bacillus coagulans

    International Nuclear Information System (INIS)

    Tawfik, Z.S.

    1992-01-01

    Radiation resistant strains of bacillus coagulans were isolated from environmental atmospheric surrounding industrial cobalt-60 irradiator. D 1 0 value of the studied isolate was found to be 3.3 KGy. Ultrastructure studies were performed on control isolates as well as on isolates exposed to challenging doses of 12, 15 and 25 KGy. These dose values were delivered at two different dose rate values 40 Gy/min and 300 Gy/min. Ultrastructure studies showed small differences due to dose rate effect. These differences were not sufficient to cause lethality changes. It was demonstrated that the growing effect of dose value is concentrated on cellular material rather than on cellular membrane damages. The severeness of cell damage, due to received dose increase, was also demonstrated. Results suggest that repeated sub culturing may lead to repair of cell damage when it is subjected to sub sterilizing doses. This fact is of special interest when the sterilizing dose might be splitted in more than one fraction at different latent periods

  1. Prevalence of Various Microbial Organisms Isolated from Dairy Goat ...

    African Journals Online (AJOL)

    Six- hundred and thirty (630) apparently normal milk samples from dairy goats in Nyeri district (Kenya) were examined over a three-month period to determine the prevalence of bacterial organisms. Bacteria were isolated in 28.7% of milk samples (181/630) either as a single bacterial organism (92.8%) or mixed bacterial ...

  2. Carbapenem-resistance and pathogenicity of bovine Acinetobacter indicus-like isolates.

    Directory of Open Access Journals (Sweden)

    Peter Klotz

    Full Text Available The objective of this study was to characterize blaOXA-23 harbouring Acinetobacter indicus-like strains from cattle including genomic and phylogenetic analyses, antimicrobial susceptibility testing and evaluation of pathogenicity in vitro and in vivo. Nasal and rectal swabs (n = 45 from cattle in Germany were screened for carbapenem-non-susceptible Acinetobacter spp. Thereby, two carbapenem resistant Acinetobacter spp. from the nasal cavities of two calves could be isolated. MALDI-TOF mass spectrometry and 16S rDNA sequencing identified these isolates as A. indicus-like. A phylogenetic tree based on partial rpoB sequences indicated closest relation of the two bovine isolates to the A. indicus type strain A648T and human clinical A. indicus isolates, while whole genome comparison revealed considerable intraspecies diversity. High mimimum inhibitory concentrations were observed for carbapenems and other antibiotics including fluoroquinolones and gentamicin. Whole genome sequencing and PCR mapping revealed that both isolates harboured blaOXA-23 localized on the chromosome and surrounded by interrupted Tn2008 transposon structures. Since the pathogenic potential of A. indicus is unknown, pathogenicity was assessed employing the Galleria (G. mellonella infection model and an in vitro cytotoxicity assay using A549 human lung epithelial cells. Pathogenicity in vivo (G. mellonella killing assay and in vitro (cytotoxicity assay of the two A. indicus-like isolates was lower compared to A. baumannii ATCC 17978 and similar to A. lwoffii ATCC 15309. The reduced pathogenicity of A. indicus compared to A. baumannii correlated with the absence of important virulence genes encoding like phospholipase C1+C2, acinetobactin outer membrane protein BauA, RND-type efflux system proteins AdeRS and AdeAB or the trimeric autotransporter adhesin Ata. The emergence of carbapenem-resistant A. indicus-like strains from cattle carrying blaOXA-23 on transposable elements and

  3. Isolation and Pathogenicity of Phytophthora Species from Poplar Plantations in Serbia

    Directory of Open Access Journals (Sweden)

    Ivan Milenković

    2018-06-01

    Full Text Available During a survey in three declining and three healthy poplar plantations in Serbia, six different Phytophthora species were obtained. Phytophthora plurivora was the most common, followed by P. pini, P. polonica, P. lacustris, P. cactorum, and P. gonapodyides. Pathogenicity of all isolated species to four-month and one-year-old cuttings of Populus hybrid clones I-214 and Pánnonia, respectively, was tested using both a soil infestation and stem inoculation test. Isolates of P. polonica, P. × cambivora, P. cryptogea, and P. × serendipita from other host plants were included as a comparison. In the soil infestation test, the most aggressive species to clone I-214 were P. plurivora, P. × serendipita, and P. pini. On clone Pánnonia, P. gonapodyides and P. pini were the most aggressive, both causing 100% mortality, followed by P. cactorum, P. × cambivora, and P. polonica. In the underbark inoculation test, the susceptibility of both poplar clones to the different Phytophthora species was largely similar, as in the soil infestation test, with the exception of P. polonica, which proved to be only weakly pathogenic to poplar bark. The most aggressive species to clone I-214 was P. pini, while on clone Pánnonia, the longest lesions and highest disease incidence were caused by P. gonapodyides. Phytophthora cactorum and P. plurivora were pathogenic to both clones, whereas P. × cambivora showed only weak pathogenicity. The implications of these findings and possible pathways of dispersion of the pathogens are discussed.

  4. Isolation, identification, characterization and antibiotic sensitivity profile of pathogenic Legionella pneumophila isolates from different water sources

    Directory of Open Access Journals (Sweden)

    Kannan Subbaram

    2017-05-01

    Conclusions: Serious and fatal L. pneumophila infections may be transmitted through water. Legionella can survive under various conditions in various water sources. L. pneumophila is the important pathogen causing human disease. Great challenge prevails to health care professionals because these Legionellae acquired antibiotic resistance to many routinely prescribed antibiotics.

  5. 16S rRNA PCR for differentiation of pathogenic and non-pathogenic leptospira isolates

    Directory of Open Access Journals (Sweden)

    Shukla J

    2003-01-01

    Full Text Available PURPOSE: To determine the risk factors, microbiological features, clinical features and other epidemiological characteristics of Nocardia keratitis seen at a tertiary eye care centre in south India. METHODS: We evaluated 31 patients with Nocardia keratitis seen over two years, from September 1999 to September 2001. Corneal scrapings were subjected to microscopy and culture using standard protocols. RESULTS: Out of 2184 corneal ulcers cultured, 31(1.42% were found to be Nocardia asteroides. All 31(100% were detected correctly by 10% potassium hydroxide wet mount preparation. The highest percentage of isolates was susceptible to gentamicin (100% followed by ciprofloxacin(93.55%. Twenty four (77.42% patients were from rural areas; 22(70.97% were agricultural workers; 29(93.55% had history of trauma; 2(6.45% had previous ocular surgery; 28(90.32% had ocular injury with soil and sand; and 22(70.97% had ocular injury while working in the agricultural fields. Ten (32.26% patients presented at our institute between 15 to 35 days of onset of illness, 26(83.87% had previous medical treatment, and 15(48.39% patients had used traditional eye medicines. The average age of the patients was 46.16 years, with a range of 11 to 75 years. No seasonal variation was observed. CONCLUSIONS: A high index of suspicion of Nocardia infection should exist in patients with a history of trauma to the eye by soil or sand. The organisms are sensitive to commonly used topical ocular antibiotics.

  6. Antibacterial Activities of Endophytic Bacteria Isolated from Taxus brevifolia Against Foodborne Pathogenic Bacteria.

    Science.gov (United States)

    Islam, Nurul; Choi, Jaehyuk; Baek, Kwang-Hyun

    2018-05-01

    Endophytes are a potential source of novel bioactive compounds with medicinal properties. In this study, 41 endophytic bacteria (EB) were isolated from tissues of a medicinally important plant Taxus brevifolia (Pacific yew). The objective was to screen all the EB isolates for their antibacterial effects against five foodborne pathogenic bacteria: Bacillus cereus ATCC10876, Staphylococcus aureus ATCC12600, Listeria monocytogenes ATCC19115, Escherichia coli ATCC43890, and Salmonella Typhimurium ATCC19585. Among the EB isolates, T. brevifolia seed (TbS)-8, T. brevifolia fleshy part of fruit (TbFl)-10, T. brevifolia leaf (TbL)-22, TbS-29, and TbL-34 exerted significant antibacterial activity against the tested foodborne pathogens. Especially TbFl-10 showed the highest antibacterial activity against all the tested bacteria and was identified as Paenibacillus kribbensis (Pk). Furthermore, an ethyl acetate extract of Pk-TbFl-10 possessed antibacterial activities against the tested five foodborne pathogenic bacteria, with zones of inhibition from 15.71 ± 2.85 to 13.01 ± 2.12 mm. Scanning electron microscopy analysis revealed ruptured, lysed, shrunk, and swollen cells of all the tested foodborne pathogens treated with the ethyl acetate extract of Pk-TbFl-10, suggesting that a metabolite(s) of Pk-TbFl-10 penetrates the cell membrane and causes cell lysis leading to cell death. Our results indicate that Pk-TbFl-10 isolated from T. brevifolia can serve as a novel source of natural antibacterial agents against foodborne pathogenic bacteria, with potential applications in the pharmaceutical industry.

  7. Isolation of Biosurfactant–Producing Bacteria with Antimicrobial Activity against Bacterial Pathogens

    Directory of Open Access Journals (Sweden)

    Siripun Sarin

    2011-01-01

    Full Text Available The aims of this research were to study biosurfactant producing bacteria isolated from soil and to determine their property and efficiency as biosurfactants in order to inhibit bacterial pathogens. The result showed that there were 8 bacterial isolates out of 136 isolates of the total biosurfactant producing bacteria screened that exhibited the diameter of clear zone more than 1.5 cm. in the oil spreading test. The highest potential of emulsifying activity (%EA24 of 54.4 and the maximum additive concentration, (%MAC of 24.2 was obtained from the fermentation broth of the G7 isolate which the G7 isolate was later identified as Pseudomonas fluorescens. Escherichia coli, Staphylococcus aureus and Psuedomonas aeruginosa were the tested bacterial pathogens that were most sensitive to the acid precipitated biosurfactant obtained from P. fluorescens G7 with the lowest minimum inhibitory concentration (MIC of 41.6 mg/ml and minimum bactericidal concentration (MBC of 41.6 mg/ml compared with the acid precipitated bisurfactants of the other isolates used in the antimicrobial activity test. The type of the separated crude biosurfactant produced by P. fluorescens G7 analyzed later by using the rhamose test, TLC and FT-IR techniques was rhamnolipid.

  8. European apple canker: morphophysiological variability and pathogenicity in isolates of Neonectria ditissima in southern Brazil

    Directory of Open Access Journals (Sweden)

    Jonatas da Silva Campos

    Full Text Available ABSTRACT: European apple canker (EC is caused by Neonectria ditissima, a pathogen officially registered as a quarantine pest in 2012. Thirty-five isolates of N. ditissima of different geographical regions of southern Brazil from apple branches showing symptoms of EC were identified by the specific pair primers Ch1 and Ch2 and analyzed concerning the virulence on Gala apple cultivar and morphophysiological characteristics. The disease symptoms were characterized and the isolates compared based on average mycelium growth (AMG, mycelium growth index (MGI, colony color, conidia type, dimensions and growth on potato dextrose agar (PDA, malt agar (AM, and synthetic SNAY (SN culture media. Nineteen isolates showed the greatest AMG on PDA, forming three growth groups of 35.56 (GI, 52.71 (GII, and 62.67mm (GIII. Seven isolates showed MGI greater than 4.0mm diameter on PDA compared with that on AM and SN. The highest conidia production was on SN, and the predominant colony color in all media was white to beige with central pigmentation of brown and borders colored in shades of beige. There were significant differences among the average dimensions of micro- and macroconidia on PDA, AM, and SN. The pathogenicity was confirmed for all isolates despite of different morphophysiological characteristics. There was no correlation among isolates morphophysiological variability, virulence, and geographical origin.

  9. Pathogenicity evaluation of native isolates of entomopathogenic fungí against andean weevil, Premnotrypes vorax (Hustache

    Directory of Open Access Journals (Sweden)

    Giselle Rivera

    2001-07-01

    Full Text Available The main goal of this study was pathogenicity evaluation of Beauveria bassiana and Metarhizium anisopliae native isolates, obtained from natural habitats and stocked potato, against potato andean weevil, Premnotrypes vorax (Hustache (COLEOPTERA: Curculionidae, and important potato insect pest in Colombia and other Andean countries. Patogenicity was determined by laboratory bioassays, using either reared insects or field captured insects. Insect rearing data are presented. Pathogenicity evaluation was express as mortality against time, estimating LT50 and LT90 for all the fungal isolates, and mortality against spore concentration, estimating CL50 for two selected isolates. In all cases, total mortality percentils were above 45%. Differences between reared and field captured insects were evident. According to obtained data one of the fungal isolates: B. bassiana 9770, obtained from R vorax larva (TL50: 4.7 days - 9.8 days; TL90: 14.1 days - 20.8 days; CL50:7.03 x 104spores/ml appears as a promisory fungal isolate for further studies. Out of this study, differences in the andean weevil, P. vorax, adult mortality, with regard to entomopathogenic fungal isolate and insect origin were manifest.

  10. Comparative pathogenicity of early and recent isolates of avian metapneumovirus subtype C in turkeys.

    Science.gov (United States)

    Velayudhan, Binu T; Noll, Sally L; Thachil, Anil J; Halvorson, David A; Shaw, Daniel P; Goyal, Sagar M; Nagaraja, Kakambi V

    2008-07-01

    The objective of the present study was to compare the pathogenicity of early and recent isolates of avian metapneumovirus subtype-C (aMPV-C) in turkeys. Two-week-old turkeys were inoculated with early and recent isolates of aMPV-C. Clinical signs were monitored. Tissues were examined for viral ribonucleic acid (RNA), lesions, and viral antigen by reverse transcription-polymerase chain reaction (RT-PCR), histopathology and immunohistochemistry, respectively. Birds infected with the recent isolate had higher clinical sign scores than those infected with the early isolate. Only the recent isolate produced a multifocal loss of cilia in the nasal turbinate of infected birds. Immunohistochemistry revealed intense staining of aMPV antigen in turbinate and trachea of birds infected with the recent isolate. The findings indicate that the recent isolate produced more severe clinical signs and lesions in turkeys compared to the early isolate. The recent isolate could be ideal for the development of a challenge model for aMPV infection in turkeys.

  11. Characteristics of pathogenic Vibrio sp. isolated from the rockfish, Sebastes schlegeli

    International Nuclear Information System (INIS)

    Kim, Jong Hwa

    1995-02-01

    At the summer time, an infectious bacterial disease occurs and damages the net cage farms of rockfish (Sebastes schlegeli) at the western coast of Korea. The symptoms of this disease include darkness of body color, ulceration of skin, anemia of gill-filaments, and congestion of operculum. In order to know the attributes of pathogenicity of this disease, the study is performed with isolated bacteria from the rockfish sampled at the fish farm, located at Taean-gun Chungcheongnam-do, from June to September in 1994. The pathogenic bacteria cna be isolated from dermal lesion, kidney, liver, and spleen of the sick fish, and classified as Vibrio sp. based on the morphological, biological, and biochemical examinations. These isolates are proliferated in BTB teepol, TCBS, TSA, XA, BHIA, media, not in SS and MacConkey media, and the optimal growth conditions for NaCl concentration, pH, and temperature are 3%, 7∼8, and 25∼30 .deg. C, respectively. They turn out to be sensitive to three chemicals such as SXT (sulfamethoxazol + trimethoprim), nalidixic acid, and tetracycline, but resistant to ampicillin and penicillin G. Finally, the virulence of infectious bacteria is appeared at both 20 .deg. C and 27 .deg. C when isolated pathogenic strains are injected into the muscle of healthy rockfish

  12. Characterization of Two Microbial Isolates from Andean Lakes in Bolivia

    Science.gov (United States)

    Demergasso, C.; Blamey, J.; Escudero, L.; Chong, G.; Casamayor, E. O.; Cabrol, N. A.; Grin, E. A.; Hock, A.; Kiss, A.; Borics, G.

    2004-01-01

    We are currently investigating the biological population present in the highest and least explored perennial lakes on earth in the Bolivian and Chilean Andes, including several volcanic crater lakes of more than 6000 m elevation, in combination of microbiological and molecular biological methods. Our samples were collected in saline lakes of the Laguna Blanca Laguna Verde area in the Bolivian Altiplano and in the Licancabur volcano crater (27 deg. 47 min S/67 deg. 47 min. W) in the ongoing project studying high altitude lakes. The main goal of the project is to look for analogies with Martian paleolakes. These Bolivian lakes can be described as Andean lakes following the classification of Chong. We have attempted to isolate pure cultures and phylogenetically characterize prokaryotes that grew under laboratory conditions. Sediment samples taken from the Licancabur crater lake (LC), Laguna Verde (LV), and Laguna Blanca (LB) were analyzed and cultured using enriched liquid media under both aerobic and anaerobic conditions. All cultures were incubated at room temperature (15 to 20 C) and under light exposure. For the reported isolates, 36 hours incubation were necessary for reaching optimal optical densities to consider them viable cultures. Ten serial dilutions starting from 1% inoculum were required to obtain a suitable enriched cell culture to transfer into solid media. Cultures on solid medium were necessary to verify the formation of colonies in order to isolate pure cultures. Different solid media were prepared using several combinations of both trace minerals and carbohydrates sources in order to fit their nutrient requirements. The microorganisms formed individual colonies on solid media enriched with tryptone, yeast extract and sodium chloride. Cells morphology was studied by optical and electronic microscopy. Rodshape morphologies were observed in most cases. Total bacterial genomic DNA was isolated from 50 ml late-exponential phase culture by using the CTAB

  13. Antibiotic resistance and pathogenicity factors in Staphylococcus aureus isolated from mastitic Sahiwal cattle.

    Science.gov (United States)

    Kumar, Ravinder; Yadav, B R; Singh, R S

    2011-03-01

    Methicillin-resistant Staphylococcus aureus (MRSA) poses a serious problem in dairy animals suffering from mastitis. In the present study, the distribution of mastitic MRSA and antibiotic resistance was studied in 107 strains of S. aureus isolated from milk samples from 195 infected udders. The characterizations pathogenic factors (adhesin and toxin genes) and antibiotic susceptibility of isolates were carried out using gene amplification and disc diffusion assays, respectively. A high prevalence of MRSA was observed in the tested isolates (13.1%). The isolates were also highly resistant to antibiotics, i.e. 36.4% were resistant to streptomycin, 33.6% to oxytetracycline, 29.9% to gentamicin and 26.2% each to chloramphenicol, pristinomycin and ciprofloxacin. A significant variation in the expression of pathogenic factors (Ig, coa and clf) was observed in these isolates. The overall distribution of adhesin genes ebp, fib, bbp, fnbB, cap5, cap8, map and cna in the isolates was found to be 69.1, 67.2, 6.5, 20.5, 60.7, 26.1, 81.3 and 8.4%, respectively. The presence of fib, fnbB, bbp and map genes was considerably greater in MRSA than in methicillin-susceptible S. aureus (MSSA) isolates. The proportions of toxin genes, namely, hlb, seb, sec, sed, seg and sei, in the isolates were found to be 94.3, 0.9, 8.4, 0.9, 10.2 and 49.5%, respectively. The proportions of agr genes I, II, III and IV were found to be 39.2, 27.1, 21.5 and 12.1%, respectively. A few isolates showed similar antibiotic-resistance patterns, which could be due to identical strains or the dissemination of the same strains among animals. These findings can be utilized in mastitis treatment programmes and antimicrobials strategies in organized herd.

  14. Isolation and Characterization of Actinomycete Antagonists of a Fungal Root Pathogen

    Science.gov (United States)

    Crawford, Don L.; Lynch, James M.; Whipps, John M.; Ousley, Margaret A.

    1993-01-01

    By use of selective media, 267 actinomycete strains were isolated from four rhizosphere-associated and four non-rhizosphere-associated British soils. Organic media with low nutrient concentrations were found to be best for isolating diverse actinomycetes while avoiding contamination and overgrowth of isolation media by eubacteria and fungi. While all isolates grew well at pHs 6.5 to 8.0, a few were unable to grow at pH 6.0 and a significant number failed to grow at pH 5.5. Eighty-two selected isolates were screened for in vitro antagonism towards Pythium ultimum by use of a Difco cornmeal agar assay procedure. Five isolates were very strong antagonists of the fungus, four were strong antagonists, and ten others were weakly antagonistic. The remaining isolates showed no antagonism by this assay. Additional studies showed that several of the P. ultimum antagonists also strongly inhibited growth of other root-pathogenic fungi. Twelve isolates showing antifungal activity in the in vitro assay were also tested for their effects on the germination and short-term growth of lettuce plants in glasshouse pot studies in the absence of pathogens. None of the actinomycetes prevented seed germination, although half of the isolates retarded seed germination and outgrowth of the plants by 1 to 3 days. During 18-day growth experiments, biomass yields of some actinomycete-inoculated plants were reduced in comparison with untreated control plants, although all plants appeared healthy and well rooted. None of the actinomycetes significantly enhanced plant growth over these short-term experiments. For some, but not all, actinomycetes, some correlations between delayed seed germination and reduced 18-day plant biomass yields were seen. For others, plant biomass yields were not reduced despite an actinomycete-associated delay in seed germination and plant outgrowth. Preliminary glasshouse experiments indicated that some of the actinomycetes protect germinating lettuce seeds against

  15. Isolation and characterization of actinomycete antagonists of a fungal root pathogen.

    Science.gov (United States)

    Crawford, D L; Lynch, J M; Whipps, J M; Ousley, M A

    1993-11-01

    By use of selective media, 267 actinomycete strains were isolated from four rhizosphere-associated and four non-rhizosphere-associated British soils. Organic media with low nutrient concentrations were found to be best for isolating diverse actinomycetes while avoiding contamination and overgrowth of isolation media by eubacteria and fungi. While all isolates grew well at pHs 6.5 to 8.0, a few were unable to grow at pH 6.0 and a significant number failed to grow at pH 5.5. Eighty-two selected isolates were screened for in vitro antagonism towards Pythium ultimum by use of a Difco cornmeal agar assay procedure. Five isolates were very strong antagonists of the fungus, four were strong antagonists, and ten others were weakly antagonistic. The remaining isolates showed no antagonism by this assay. Additional studies showed that several of the P. ultimum antagonists also strongly inhibited growth of other root-pathogenic fungi. Twelve isolates showing antifungal activity in the in vitro assay were also tested for their effects on the germination and short-term growth of lettuce plants in glasshouse pot studies in the absence of pathogens. None of the actinomycetes prevented seed germination, although half of the isolates retarded seed germination and outgrowth of the plants by 1 to 3 days. During 18-day growth experiments, biomass yields of some actinomycete-inoculated plants were reduced in comparison with untreated control plants, although all plants appeared healthy and well rooted. None of the actinomycetes significantly enhanced plant growth over these short-term experiments. For some, but not all, actinomycetes, some correlations between delayed seed germination and reduced 18-day plant biomass yields were seen. For others, plant biomass yields were not reduced despite an actinomycete-associated delay in seed germination and plant outgrowth. Preliminary glasshouse experiments indicated that some of the actinomycetes protect germinating lettuce seeds against

  16. Selection and identification of non-pathogenic bacteria isolated from fermented pickles with antagonistic properties against two shrimp pathogens.

    Science.gov (United States)

    Zokaeifar, Hadi; Balcázar, José Luis; Kamarudin, Mohd Salleh; Sijam, Kamaruzaman; Arshad, Aziz; Saad, Che Roos

    2012-06-01

    In this study, potential probiotic strains were isolated from fermented pickles based on antagonistic activity against two shrimp pathogens (Vibrio harveyi and Vibrio parahaemolyticus). Two strains L10 and G1 were identified by biochemical tests, followed by16S ribosomal RNA gene sequence analysis as Bacillus subtilis, and characterized by PCR amplification of repetitive bacterial DNA elements (Rep-PCR). Subsequently, B. subtilis L10 and G1 strains were tested for antibacterial activity under different physical conditions, including culture medium, salinity, pH and temperature using the agar well diffusion assay. Among the different culture media, LB broth was the most suitable medium for antibacterial production. Both strains showed the highest level of antibacterial activity against two pathogens at 30 °C and 1.0% NaCl. Under the pH conditions, strain G1 showed the greatest activity against V. harveyi at pH 7.3-8.0 and against V. parahaemolyticus at pH 6.0-8.0, whereas strain L10 showed the greatest activity against two pathogens at pH 7.3. The cell-free supernatants of both strains were treated with four different enzymes in order to characterize the antibacterial substances against V. harveyi. The result showed considerable reduction of antibacterial activity for both strains, indicating the proteinaceous nature of the antibacterial substances. A wide range of tolerance to NaCl, pH and temperature was also recorded for both strains. In addition, both strains showed no virulence effect in juvenile shrimp Litopenaeus vannamei. On the basis of these results and safety of strains to L. vannamei, they may be considered for future challenge experiments in shrimp as a very promising alternative to the use of antibiotics.

  17. Pharmacological synergism of bee venom and melittin with antibiotics and plant secondary metabolites against multi-drug resistant microbial pathogens.

    Science.gov (United States)

    Al-Ani, Issam; Zimmermann, Stefan; Reichling, Jürgen; Wink, Michael

    2015-02-15

    The goal of this study was to investigate the antimicrobial activity of bee venom and its main component, melittin, alone or in two-drug and three-drug combinations with antibiotics (vancomycin, oxacillin, and amikacin) or antimicrobial plant secondary metabolites (carvacrol, benzyl isothiocyanate, the alkaloids sanguinarine and berberine) against drug-sensitive and antibiotic-resistant microbial pathogens. The secondary metabolites were selected corresponding to the molecular targets to which they are directed, being different from those of melittin and the antibiotics. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were evaluated by the standard broth microdilution method, while synergistic or additive interactions were assessed by checkerboard dilution and time-kill curve assays. Bee venom and melittin exhibited a broad spectrum of antibacterial activity against 51 strains of both Gram-positive and Gram-negative bacteria with strong anti-MRSA and anti-VRE activity (MIC values between 6 and 800 µg/ml). Moreover, bee venom and melittin showed significant antifungal activity (MIC values between 30 and 100 µg/ml). Carvacrol displayed bactericidal activity, while BITC exhibited bacteriostatic activity against all MRSA and VRE strains tested (reference strains and clinical isolates), both compounds showed a remarkable fungicidal activity with minimum fungicidal concentration (MFC) values between 30 and 200 µg/ml. The DNA intercalating alkaloid sanguinarine showed bactericidal activity against MRSA NCTC 10442 (MBC 20 µg/ml), while berberine exhibited bacteriostatic activity against MRSA NCTC 10442 (MIC 40 µg/ml). Checkerboard dilution tests mostly revealed synergism of two-drug combinations against all the tested microorganisms with FIC indexes between 0.24 and 0.50, except for rapidly growing mycobacteria in which combinations exerted an additive effect (FICI = 0.75-1). In time-kill assays all three

  18. Limitations of the Current Microbial Identification System for Identification of Clinical Yeast Isolates

    Science.gov (United States)

    Kellogg, James A.; Bankert, David A.; Chaturvedi, Vishnu

    1998-01-01

    The ability of the rapid, computerized Microbial Identification System (MIS; Microbial ID, Inc.) to identify a variety of clinical isolates of yeast species was compared to the abilities of a combination of tests including the Yeast Biochemical Card (bioMerieux Vitek), determination of microscopic morphology on cornmeal agar with Tween 80, and when necessary, conventional biochemical tests and/or the API 20C Aux system (bioMerieux Vitek) to identify the same yeast isolates. The MIS chromatographically analyzes cellular fatty acids and compares the results with the fatty acid profiles in its database. Yeast isolates were subcultured onto Sabouraud dextrose agar and were incubated at 28°C for 24 h. The resulting colonies were saponified, methylated, extracted, and chromatographically analyzed (by version 3.8 of the MIS YSTCLN database) according to the manufacturer’s instructions. Of 477 isolates of 23 species tested, 448 (94%) were given species names by the MIS and 29 (6%) were unidentified (specified as “no match” by the MIS). Of the 448 isolates given names by the MIS, only 335 (75%) of the identifications were correct to the species level. While the MIS correctly identified only 102 (82%) of 124 isolates of Candida glabrata, the predictive value of an MIS identification of unknown isolates as C. glabrata was 100% (102 of 102) because no isolates of other species were misidentified as C. glabrata. In contrast, while the MIS correctly identified 100% (15 of 15) of the isolates of Saccharomyces cerevisiae, the predictive value of an MIS identification of unknown isolates as S. cerevisiae was only 47% (15 of 32), because 17 isolates of C. glabrata were misidentified as S. cerevisiae. The low predictive values for accuracy associated with MIS identifications for most of the remaining yeast species indicate that the procedure and/or database for the system need to be improved. PMID:9574676

  19. Draft genome sequences of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from human patients.

    Science.gov (United States)

    Mendoza-Olazarán, Soraya; Garcia-Mazcorro, José F; Morfín-Otero, Rayo; Villarreal-Treviño, Licet; Camacho-Ortiz, Adrián; Rodríguez-Noriega, Eduardo; Bocanegra-Ibarias, Paola; Maldonado-Garza, Héctor J; Dowd, Scot E; Garza-González, Elvira

    2017-01-01

    Herein, we report the draft-genome sequences and annotation of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from humans. One strain (SC-57) was isolated from blood from a male patient in May 2006 and the other (SC-532) from a catheter from a male patient in June 2006. Similar to other genomes of Staphylococcus species, most genes (42%) of both strains are involved in metabolism of amino acids and derivatives, carbohydrates and proteins. Eighty (4%) genes are involved in virulence, disease, and defense and both species show phenotypic low biofilm production and evidence of increased antibiotic resistance associated to biofilm production. From both isolates, a new Staphylococcal Cassette Chromosome mec was detected: mec class A, ccr type 1. This is the first report of whole genome sequences of opportunistic S. cohnii isolated from human patients.

  20. Isolation of pathogenic Yersinia enterocolitica 1B/O:8 from Apodemus mice in Japan.

    Science.gov (United States)

    Oda, Shinya; Kabeya, Hidenori; Sato, Shingo; Shimonagane, Ai; Inoue, Kai; Hayashidani, Hideki; Takada, Nobuhiro; Fujita, Hiromi; Kawabata, Hiroki; Maruyama, Soichi

    2015-01-01

    Yersinia enterocolitica was isolated from 15.7% (88/560) of wild rodents captured in 15 prefectures in Japan. Prevalences by rodent species were 18.0% (70/388) in Japanese field mice (Apodemus speciosus), 20% (14/71) in small Japanese field mice (Apodemus argenteus), and 11% (4/38) in gray red-backed vole (Myodes rufocanus bedfordiae), suggesting that these rodent species are important reservoirs of Y. enterocolitica. Although most of the isolates were identified as biotype 1A, the pathogenic bioserotype 1B/O:8 was detected in one of the A. speciosus and in three of the A. argenteus captured in Aomori Prefecture. It is suggested that Apodemus mice may be an important reservoir of Y. enterocolitica, and that there are foci of the pathogenic bioserotype 1B/O:8 in Aomori Prefecture, because human sporadic cases by the serotype have been reported in this prefecture.

  1. Pathogenic characteristics of yeasts isolated from vaginal secretion preserved under mineral oil

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    B Severo Gomes

    2011-01-01

    Full Text Available In order to evaluate the pathogenicity of yeasts isolated from vaginal secretion of pregnant and non-pregnant women - stored in mineral oil at the URM Mycology Collection, Department of Mycology, Federal University of Pernambuco - 30 samples belonging to the genera Candida, Rhodotorula, Trichosporon, and Kloeckera, were studied regarding their pathogenic characteristics, ability to grow at room temperature (28°C ± 1°C, 37°C, and 42°C for 72 hours, and production of both phospholipase and proteinase. Results showed that all 30 isolates (100% were able to grow at room temperature and 37°C, and that 17 samples (57% were able to grow at 42°C. Evaluation of enzymatic activity showed protease activity in only two isolates (7%, namely C. maritima and C. obtusa. Phospholipase activity was detected in 20 isolates (67% using soy lecithin as substrate at different temperatures. The characterization of yeasts isolated from vaginal secretion and determination of their enzymatic activity may contribute to understanding the epidemiology of vulvovaginitis and assist in the treatment of patients.

  2. Screening and evaluation of local bacteria isolated from shellfish as potential probiotics against pathogenic Vibrios.

    Science.gov (United States)

    Jasmin, M Y; Wagaman, Hazimah; Yin, Tan Ai; Ina-salwany, M Y; Daud, H M; Karim, Murni

    2016-07-01

    The present study was carried out to isolate, screen and evaluate potential candidates of local bacteria isolated from tiger shrimp Penaeus monodon and slipper cupped oysters Crassostrea iredalei as probiotics in shellfish aquaculture. A total of 144 of bacteria were successfully isolated from the intestine and stomach of 20 tails of healthy adult tiger shrimp P. monodon, while 136 were successfully isolated from the digestive tract, gills and inner shells of 10 healthy adult C. iredalei. The number of potential isolates was narrowed down to two from tiger shrimp, and one from slipper cupped oyster after in vitro screening assays. The three isolates, labeled as G11, I24 and S66, were identified as Virgibacillus sp., Bacillus sp. and Exiquobacterium sp., respectively, using 16S rDNA gene analysis. The antagonistic ability of the isolates towards Vibrio alginolyticus and Vibrio harveyi were conducted in stagnant and liquid modes via spot lawn and broth co-culture assay, respectively. In these assays, all the potential probionts were inhibitory to both pathogenic vibrios. In the in-vivo assay, Artemia was used as host and treated with different concentrations of potential probionts (10(4), 10(6) and 10(8) CFU ml(-1)), and challenged with V. alginolyticus and V. harveyi at 105 CFU ml(-1), respectively. Artemia treated with probiont G11 at all concentrations and challenged with V. alginolyticus had increased survival (70 ? 80 %), which was significantly higher as compared with group with only the pathogen (20 %). Meanwhile, probiont I24 increased the survival of Artemia by 70 % at a concentration of 10(8) CFU ml(-1) after being challenged with V. alginolyticus and Artemia treated with 10(6) CFU ml(-1) of probiont S66 had increased survival of 90% after being challenged with V. harveyi. Thus, the three isolates might have potential applications as probiotics in shellfish aquaculture against vibriosis. ?

  3. The effect of interactions between a bacterial strain isolated from drinking water and a pathogen surrogate on biofilms formation diverged under static vs flow conditions.

    Science.gov (United States)

    Dai, D; Raskin, L; Xi, C

    2017-12-01

    Interactions with water bacteria affect the incorporation of pathogens into biofilms and thus pathogen control in drinking water systems. This study was to examine the impact of static vs flow conditions on interactions between a pathogen and a water bacterium on pathogen biofilm formation under laboratory settings. A pathogen surrogate Escherichia coli and a drinking water isolate Stenotrophomonas maltophilia was selected for this study. Biofilm growth was examined under two distinct conditions, in flow cells with continuous medium supply vs in static microtitre plates with batch culture. E. coli biofilm was greatly stimulated (c. 2-1000 times faster) with the presence of S. maltophilia in flow cells, but surprisingly inhibited (c. 65-95% less biomass) in microtitre plates. These divergent effects were explained through various aspects including surface attachment, cellular growth, extracellular signals and autoaggregation. Interactions with the same water bacterium resulted in different effects on E. coli biofilm formation when culture conditions changed from static to flow. This study highlights the complexity of species interactions on biofilm formation and suggests that environmental conditions such as the flow regime can be taken into consideration for the management of microbial contamination in drinking water systems. © 2017 The Society for Applied Microbiology.

  4. Genotypes and pathogenicity of cellulitis isolates reveal traits that modulate APEC virulence.

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    Nicolle Lima Barbieri

    Full Text Available We characterized 144 Escherichia coli isolates from severe cellulitis lesions in broiler chickens from South Brazil. Analysis of susceptibility to 15 antimicrobials revealed frequencies of resistance of less than 30% for most antimicrobials except tetracycline (70% and sulphonamides (60%. The genotyping of 34 virulence-associated genes revealed that all the isolates harbored virulence factors related to adhesion, iron acquisition and serum resistance, which are characteristic of the avian pathogenic E. coli (APEC pathotype. ColV plasmid-associated genes (cvi/cva, iroN, iss, iucD, sitD, traT, tsh were especially frequent among the isolates (from 66.6% to 89.6%. According to the Clermont method of ECOR phylogenetic typing, isolates belonged to group D (47.2%, to group A (27.8%, to group B2 (17.4% and to group B1 (7.6%; the group B2 isolates contained the highest number of virulence-associated genes. Clonal relationship analysis using the ARDRA method revealed a similarity level of 57% or higher among isolates, but no endemic clone. The virulence of the isolates was confirmed in vivo in one-day-old chicks. Most isolates (72.9% killed all infected chicks within 7 days, and 65 isolates (38.1% killed most of them within 24 hours. In order to analyze differences in virulence among the APEC isolates, we created a pathogenicity score by combining the times of death with the clinical symptoms noted. By looking for significant associations between the presence of virulence-associated genes and the pathogenicity score, we found that the presence of genes for invasins ibeA and gimB and for group II capsule KpsMTII increased virulence, while the presence of pic decreased virulence. The fact that ibeA, gimB and KpsMTII are characteristic of neonatal meningitis E. coli (NMEC suggests that genes of NMEC in APEC increase virulence of strains.

  5. Diverse pathogenicity of equine herpesvirus 1 (EHV-1) isolates in CBA mouse model.

    Science.gov (United States)

    Yu, Mi Htay Htay; Kasem, Samy Gomaa Ahmed; Tsujimura, Koji; Matsumura, Tomio; Yanai, Tokuma; Yamaguchi, Tsuyoshi; Ohya, Kenji; Fukushi, Hideto

    2010-03-01

    The pathogenicity of equine herpesvirus 1 (EHV-1) isolates of Japan were evaluated by using the CBA mouse model. CBA mice were inoculated with eight Japanese EHV-1 strains (89c1, 90c16, 90c18, 97c11, 98c12, 00c19, 01c1 and HH-1) and one British strain (Ab4p). 89c1 caused slight body weight loss and nervous signs in mice at 8 days post infection (dpi). Severe weight loss and nervous signs were observed in mice inoculated with Ab4p at 6 dpi. The other strains did not cause apparent clinical signs. Infectious viruses were recovered from the lungs of all groups at 2 dpi. Histopathological analysis revealed interstitial pneumonia in the lungs of all mice inoculated with EHV-1. Encephalitis or meningoencephalitis was observed in the brains of mice inoculated with 89c1, 90c18, 97c11, 98c12, 01c1 and Ab4p. Japanese EHV-1 strains showed low pathogenicity in CBA mice, whereas the sequential affects of infection are similar to those of the highly pathogenic strain Ab4p. These results suggest that field isolates of EHV-1 have varying degrees of pathogenicity in CBA mice.

  6. Isolation of pathogenic Yersinia enterocolitica strains from different sources in Izmir region, Turkey.

    Science.gov (United States)

    Bozcal, Elif; Uzel, Atac; Aydemir, Sohret; Skurnik, Mikael

    2015-11-01

    Yersinia enterocolitica is a foodborne pathogen that is very rarely encountered in Turkey. In this work, several human, porcine, and environmental samples collected from Izmir region in Turkey were examined for the presence of Y. enterocolitica using different cultivation and enrichment methods. A total of nine pathogenic Y. enterocolitica strains were isolated; five strains from pig stool and manure samples and four strains from waste water samples. On the other hand, no Y. enterocolitica was isolated from human diarrheal stool samples (n = 102) and from 12 gulf, canal, municipal pool, and well water samples. Biochemical and serological characterization of the nine Y. enterocolitica strains revealed that they belonged to three different bioserotypes: 4/O:3, 2/O:9, and 2/O:5,27. All the strains were deemed pathogenic based on virulence factor-specific PCR analysis. Detection of pathogenic Y. enterocolitica strains from the pig and waste water samples from the Izmir region indicates that Y. enterocolitica is a potential risk for public health.

  7. Incidence of bovine clinical mastitis in Jammu region and antibiogram of isolated pathogens

    OpenAIRE

    Adil Majid Bhat; Jasvinder Singh Soodan; Rajiv Singh; Ishfaq Ahmad Dhobi; Tufail Hussain; Mohammad Yousuf Dar; Muheet Mir

    2017-01-01

    Aim: This study was conducted to evaluate the incidence of clinical mastitis in bovines of Jammu region, to identify the infectious organisms responsible for it, and the antimicrobial sensitivity of isolated pathogens. Materials and Methods: The study was conducted on cases that were presented to the Medicine Division of Teaching Veterinary Clinical Complex, Faculty of Veterinary Sciences and Animal Husbandry, R.S. Pura, Jammu, Jammu and Kashmir. A total of 260 cases of bovines were prese...

  8. Effect of ozonation on microbial fish pathogens, ammonia, nitrate, nitrite, and bod in simulated reuse hatchery water

    Energy Technology Data Exchange (ETDEWEB)

    Colberg, P.J.; Lingg, A.J.

    1978-10-01

    The effectiveness of ozone for eliminating fish pathogens and reducing nitrite, ammonia, and BOD associated with reuse hatchery systems was evaluated. Comparative survival rates of four bacterial fish pathogens and a bacterium-protozoan population during batch and continuous flow ozonation indicated a specific microbial ozone demand during batch treatment and 99% mortality of pathogens during continuous flow treatment. Oxidation of carbon and nitrite by ozone was rapid at low ozone concentrations; carbon and ammonia oxidation rates were pH dependent. The oxidation capacity of ozone in water was greatest at elevated pH even though lower ozone concentrations were used. Ozone treatment appears to be successful for disinfecting hatchery makeup water for recycling. However, the economics of such treatment are yet to be determined. (10 graphs, 28 references, 1 table)

  9. Bioflocculation of Basic Dye onto Isolated Microbial Biopolymers

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    M. Elkady

    2017-10-01

    Full Text Available Three purified biopolymers isolated from Bacillus velezensis (40B, Bacillus mojavensis (32A and Pseudomonas (38A strains were evaluated for dye decolourization as bioflocculants. The decolourization capacity of the three polymers was inspected using C.I 28 basic yellow dye as hazardous pollutant. The chemical compositions of these purified biopolymers were considered by HPLC and FTIR spectrum. The decolourization efficiency of the three purified biopolymers was determined using both real dye polluted wastewater (discharged from AKSA EGYPT acrylic fibres industry and simulated synthetic wastewater. The maximum decolourization efficiencies of the purified biopolymers of the three studied strains (40B, (32A and (38A were 91, 89 and 88 %, respectively. The equilibrium of dye sorption process onto biopolymers was described using Langmuir isotherm equation. However, its kinetics follows the pseudo second order model. The thermodynamic examination investigated the exothermic and spontaneous nature of the decolourization process using the purified biopolymers.

  10. Isolation and Pathogenicity of Streptococcus iniae in Cultured Red Hybrid Tilapia in Malaysia.

    Science.gov (United States)

    Rahmatullah, M; Ariff, M; Kahieshesfandiari, M; Daud, H M; Zamri-Saad, M; Sabri, M Y; Amal, M N A; Ina-Salwany, M Y

    2017-12-01

    This study describes the isolation and pathogenicity of Streptococcus iniae in cultured red hybrid tilapia (Nile Tilapia Oreochromis niloticus × Mozambique Tilapia O. mossambicus) in Malaysia. The isolated gram-positive S. iniae appeared punctiform, transparently white, catalase and oxidase negative and produced complete β-hemolysis on blood agar, while a PCR assay resulted in the amplification of the 16 S rRNA gene and lactate oxidase encoded genes. The isolate was sensitive to tetracycline, vancomycin, and bacitracin but was resistant to streptomycin, ampicillin, penicillin, and erythromycin. Pathogenicity trials conducted in local red hybrid tilapia (mean ± SE = 20.00 ± 0.45 g) showed 90.0, 96.7, and 100.0% mortality within 14 d postinfection following intraperitoneal exposure to 10 4 , 10 6 , and 10 8 CFU/mL of the pathogen, respectively. The clinical signs included erratic swimming, lethargy, and inappetance at 6 h postinfection, while mortality was recorded at less than 24 h postinfection in all infected groups. The LD 50-336 h of S. iniae against the red hybrid tilapia was 10 2 CFU/mL. The post mortem examinations revealed congested livers, kidneys, and spleens of the infected fish. This is the first report of S. iniae experimental infection in cultured red hybrid tilapia in Malaysia. Received January 20, 2017; accepted July 16, 2017.

  11. Co-occurrence of pathogenic and non-pathogenic Fusarium decemcellulare and Lasiodiplodia theobromae isolates in cushion galls disease of cacao (Theobroma cacao L.

    Directory of Open Access Journals (Sweden)

    Castillo Daynet Sosa del

    2016-04-01

    Full Text Available Flowery cushion gall of cacao is a disease complex with six types. Fusarium decemcellulare have been isolated from both flowery and green point galls and recognized as the etiological agent of the disease. In the present work we: i identified by ITS-rDNA sequencing and/or taxonomy the cultivable fungal species or Operative Taxonomic Units (OTUs associated with the five symptoms of cushion galls in cacao from Venezuela, and ii determined the gall inducing capacity on cacao peeled seeds after 45 days of inoculation with suspensions of mycelia/ spores from distinct isolate types. The whole isolate collection rendered an abundance of 113 isolates with a richness of 39 OTUs (27 and eight identified at the species or genera levels, respectively, and in unidentified fungi. The dominant recovered species (≈36% were F. decemcellulare and Lasiodiplodia theobromae. Some isolates of F. decemcellulare, L. theobromae, F. equiseti, Fusarium spp., F. solani, F. incarnatum, Rhizocthonia solani and Penicillium sp. were pathogenic. Some other isolates of the first six mentioned taxa behave as non-pathogenic. Furthermore, pathogenic and non-pathogenic isolates can also co-occur within a single plant and gall type. Moreover, 2-5 species within a single gall symptom in a single tree were identified (not necessarily at the same point in the tree, indicating a broad diversity of co-occurring taxa.

  12. Near ultraviolet radiation (280-400 nm): Direct and indirect effects on microbial pathogens

    International Nuclear Information System (INIS)

    Asthana, A.

    1993-01-01

    Responses of pigmented pathogenic fungi and E. coli strains differing in DNA repair and catalase proficiency to direct and indirect effects of ultraviolet radiation were evaluated. Pigments in the four fungal pathogens of Citrus differed in their ability to protect against direct UV and damage by UV-A -mediated phototoxins of both host and non-host origin. UV-A and UV-B did not inactivate the fungal species. Differential protection in wild type strains of the two Fusarium spp. and in the wild type strains of the two Penicilium spp. against UV-C was observed. Wild type and mutants with altered coloration in Penicilium spp. protected to varying extent against both α-T and 8-MOP in the presence of UV-A. UV-B irradiation of E. coli resulted in inactivation of strains deficient in DNA excision repair. Plasmid DNA damaged in vitro by UV-B from lamp systems as well as by sunlight, and transformed in vivo into bacterial cells lacking specific nucleases showed reduced transformation in DNA excision repair strains. UV-B enriched wavelengths isolated from a solar simulator affected plasmid DNA in a similar manner as UV-B from lamp systems. Sunlight, however affected the membrane of whole cells. Concentration of foliar furanocoumarins of Citrus jambhiri decreased with UV-B irradiation. Phototoxicity to Fusarium spp. was accounted for, in part, by furanocoumarins, psoralen and bergapten (5-MOP) and others. Pure psoralen and 5-MOP affected both Fusarium spp. similarly and carotenoids protected only partially in the wild type strains. Citrus targetted the cell membrane in Fusarium spp.l and in E. coli strains; carotenoids in both of which protected against such damage. Loss in structural integrity of plasmid DNA when treated with citral and UV-A correlated with loss in transforming activity. Biological damage to membrane and DNA was due to the production of hydrogen peroxide. Fruit-rot pathogens Penicilium spp. were not affected by either furanocoumarins or citrals

  13. Microbial Gas Generation Under Expected Waste Isolation Pilot Plant Repository Conditions: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Gillow, J.B.; Francis, A.

    2011-07-01

    Gas generation from the microbial degradation of the organic constituents of transuranic (TRU) waste under conditions expected in the Waste Isolation Pilot Plant (WIPP) was investigated. The biodegradation of mixed cellulosic materials and electron-beam irradiated plastic and rubber materials (polyethylene, polyvinylchloride, hypalon, leaded hypalon, and neoprene) was examined. We evaluated the effects of environmental variables such as initial atmosphere (air or nitrogen), water content (humid ({approx}70% relative humidity, RH) and brine inundated), and nutrient amendments (nitogen phosphate, yeast extract, and excess nitrate) on microbial gas generation. Total gas production was determined by pressure measurement and carbon dioxide (CO{sub 2}) and methane (CH{sub 4}) were analyzed by gas chromatography; cellulose degradation products in solution were analyzed by high-performance liquid chromatography. Microbial populations in the samples were determined by direct microscopy and molecular analysis. The results of this work are summarized.

  14. Microbial Gas Generation Under Expected Waste Isolation Pilot Plant Repository Conditions: Final Report

    International Nuclear Information System (INIS)

    Gillow, J.B.; Francis, A.

    2011-01-01

    Gas generation from the microbial degradation of the organic constituents of transuranic (TRU) waste under conditions expected in the Waste Isolation Pilot Plant (WIPP) was investigated. The biodegradation of mixed cellulosic materials and electron-beam irradiated plastic and rubber materials (polyethylene, polyvinylchloride, hypalon, leaded hypalon, and neoprene) was examined. We evaluated the effects of environmental variables such as initial atmosphere (air or nitrogen), water content (humid (∼70% relative humidity, RH) and brine inundated), and nutrient amendments (nitogen phosphate, yeast extract, and excess nitrate) on microbial gas generation. Total gas production was determined by pressure measurement and carbon dioxide (CO 2 ) and methane (CH 4 ) were analyzed by gas chromatography; cellulose degradation products in solution were analyzed by high-performance liquid chromatography. Microbial populations in the samples were determined by direct microscopy and molecular analysis. The results of this work are summarized.

  15. Isolation and characterization of the microbial community of a freshwater distribution system

    International Nuclear Information System (INIS)

    Balamurugan, P.; Subba Rao, T.

    2015-01-01

    This investigation provides generic information on culturable and non-culturable microbial community of a freshwater distribution system. Culture based and culture independent (16S rRNA gene sequencing) techniques were used to identify the resident microbial community of the system. Selective isolation of the fouling bacteria such as biofilm formers and corrosion causing bacteria was also attempted. Denaturing gradient gel electrophoresis (DGGE) was carried out and the bands were sequenced to obtain the diversity of the total bacterial types. Pseudomonas aeruginosa was predominantly observed in most of the samples. A variety of bacteria, related to groups such as Cyanobacteria, Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes were identified. The study highlights the relevance of the observed microbial diversity with respect to material deterioration in a freshwater distribution system, which can aid in designing effective control methods. (author)

  16. Inhibitory Effect of Lactobacillus reuteri on Some Pathogenic Bacteria Isolated From Women With Bacterial Vaginosis

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    Eslami

    2014-08-01

    Full Text Available Background Considering the high prevalence of bacterial vaginosis and its association with urinary tract infection in women and treatment of gynecologic problems occur when a high recurrence of bacterial vaginosis is often treated with antibiotics. Objectives The purpose of this study was to investigate the inhibitory effect of Lactobacillus reuteri on pathogenic bacteria isolated from women with bacterial vaginosis. Materials and Methods Ninety-six samples were obtained from vaginal discharge of women with bacterial vaginosis by a gynecologist with a Dacron swab and put in sterile tubes containing TSB broth and Thioglycollate broth. Then were immediately sent to the laboratory in cold chain for further assessment. Afterward, culture was transferred on blood agar, EMB, Palcam and differential diagnosis environments. Then cultures were incubated for 24 hours at 37 °C. Lactobacillus reuteri strains were cultured in MRS environment and transferred to laboratory. After purification of pathogenic bacteria, Lactobacillus reuteri inhibitory effect on pathogenic bacteria was evaluated by minimum inhibitory concentration (MIC and antibiogram. Statistical analysis was performed using SPSS software v.16. Results The results of this study demonstrated the inhibitory effect of Lactobacillus reuteri on some pathogenic bacteria that cause bacterial, including Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus agalactiae, Enterococcus, Listeria monocytogenes and E. coli. Microscopic examination of stained smears of most Lactobacillus and pathogenic bacteria showed reduced. The prevalence of abnormal vaginal discharge, history of drug use, contraceptive methods and douching were 61%, 55%, 42% and 13%, respectively. Significant difference was observed between the use and non-use of IUD in women with bacterial. Conclusions Our findings indicated the inhibitory effect of Lactobacillus reuteri on pathogenic bacteria that

  17. The response of CD1d-restricted invariant NKT cells to microbial pathogens and their products

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    Luc eVan Kaer

    2015-05-01

    Full Text Available Invariant natural killer T (iNKT cells become activated during a wide variety of infections. This includes organisms lacking cognate CD1d-binding glycolipid antigens recognized by the semi-invariant T cell receptor of iNKT cells. Additional studies have shown that iNKT cells also become activated in vivo in response to microbial products such as bacterial lipopolysaccharide, a potent inducer of cytokine production in antigen-presenting cells (APCs. Other studies have shown that iNKT cells are highly responsive to stimulation by cytokines such as interleukin-12. These findings have led to the concept that microbial pathogens can activate iNKT cells either directly via glycolipids, or indirectly by inducing cytokine production in APCs. iNKT cells activated in this manner produce multiple cytokines that can influence the outcome of infection, usually in favor of the host, although potent iNKT cell activation may contribute to an uncontrolled cytokine storm and sepsis. One aspect of the response of iNKT cells to microbial pathogens is that it is short-lived and followed by an extended time period of unresponsiveness to reactivation. This refractory period may represent a means to avoid chronic activation and cytokine production by iNKT cells, thus protecting the host against some of the negative effects of iNKT cell activation, but potentially putting the host at risk for secondary infections. These effects of microbial pathogens and their products on iNKT cells are not only important for understanding the role of these cells in immune responses against infections but also for the development of iNKT cell-based therapies.

  18. Phylogenetic analysis, fumonisin production and pathogenicity of Fusarium fujikuroi strains isolated from rice in the Philippines.

    Science.gov (United States)

    Cruz, Alejandra; Marín, Patricia; González-Jaén, M Teresa; Aguilar, Kristel Grace I; Cumagun, Christian Joseph R

    2013-09-01

    Fusarium fujikuroi Nirenberg is a maize and rice pathogen causing important agricultural losses and produces fumonisins - mycotoxins which pose health risk to humans and farm animals. However, little information is available about the phylogenetics of this species and its ability to produce fumonisins in rice. We studied 32 strains isolated from rice in the Philippines and performed a phylogenetic analysis using the partial sequence of Elongation Factor 1 alpha (EF-1α) including isolates belonging to closely related species. Fumonisin B1 (FB1 ) production was analyzed in 7-day-old cultures grown in fumonisin-inducing medium by an enzyme-linked immunosorbent assay-based method and by real-time reverse transcriptase-polymerase chain reaction using primers for FUM1 gene, a key gene in fumonisin biosynthesis. Nucleotide diversities per site (π) were 0.00024 ± 0.00022 (standard deviation) for the 32 F. fujikuroi strains from the Philippines and 0.00189 ± 0.00143 for all 34 F. fujikuroi strains, respectively. F. fujikuroi isolates grouped into one cluster separated from the rest of isolates belonging to the closely related F. proliferatum and showed very low variability, irrespective of their geographic origin. The cluster containing strains of F. proliferatum showed higher intraspecific variability than F. fujikuroi. Thirteen of the 32 strains analyzed were FB1 producers (40.62%), with production ranging from 0.386 to 223.83 ppm. All isolates analyzed showed FUM1 gene expression above 1 and higher than the CT value of the non-template control sample. Both seedling stunting and elongation were induced by the isolates in comparison with the control. F. fujikuroi are distinct from F. proliferatum isolates based on phytogenetic analysis and are potential fumonisin producers because all are positive for FUM1 gene expression. No relationship between fumonisin production and pathogenicity could be observed. © 2013 Society of Chemical Industry.

  19. Pathogenic ability and saline stress tolerance of two Fusarium isolates from Odontesthes bonariensis eggs.

    Science.gov (United States)

    Pacheco Marino, Suani G; Cabello, Marta N; Dinolfo, María I; Stenglein, Sebastián A; Saparrat, Mario C N; Salibián, Alfredo

    2016-01-01

    Several fungal species represent a potential risk to embryos of Odontesthes bonariensis (Cuvier and Valenciennes, 1835), a euryhaline freshwater fish that lives in the Pampean inland waters and has potential economic relevance. To identify two fungi isolated from O. bonariensis eggs exposed to saline conditions and to characterize their pathogenicity and tolerance to sodium chloride solutions. The isolates were identified by morphological features, and a preliminar phylogenetic analysis using sequences of translation elongation factor 1-alpha (EF-1α) and calmodulin (CAM) was performed. Koch's postulates were tested to identify the causative agent of fungal infection. The influence of NaCl on the fungal growth was evaluated in in vitro assays. The isolates LPSC 1001 and 1002 were identified as representatives of the genus Fusarium, and belonging to the Fusarium incarnatum-Fusarium equiseti species complex (FIESC) and the Fusarium solani species complex (FSSC), respectively. Histological observations on eggs exposed in vitro to both isolates in infectivity assays confirmed the ability of the fungal isolates to penetrate to egg's chorionic membrane, leading to the death of embryos. Increasing NaCl concentration in the culture medium reduced the growth of the isolates LPSC 1001 and 1002, being completely inhibited at 160 and 120g/l NaCl respectively. The isolates LPSC 1001 (FIESC) and 1002 (FSSC) were identified as fungal pathogens to O. bonariensis eggs. The use of NaCl solutions as antifungal treatment was not effective to control the infection with these strains. Copyright © 2014 Asociación Española de Micología. Published by Elsevier Espana. All rights reserved.

  20. Isolation, Identification, and Characterization of a New Highly Pathogenic Field Isolate of Mycobacterium avium spp. avium

    Directory of Open Access Journals (Sweden)

    Liangquan Zhu

    2018-01-01

    Full Text Available Avian tuberculosis is a chronic, contagious zoonotic disease affecting birds, mammals, and humans. The disease is most often caused by Mycobacterium avium spp. avium (MAA. Strain resources are important for research on avian tuberculosis and vaccine development. However, there has been little reported about the newly identified MAA strain in recent years in China. In this study, a new strain was isolated from a fowl with symptoms of avian tuberculosis by bacterial culture. The isolated strain was identified to be MAA by culture, staining, and biochemical and genetic analysis, except for different colony morphology. The isolated strain was Ziehl-Zeelsen staining positive, resistant to p-nitrobenzoic acid, and negative for niacin production, Tween-80 hydrolysis, heat stable catalase and nitrate production. The strain had the DnaJ gene, IS1245, and IS901, as well. Serum agglutination indicated that the MAA strain was of serotype 1. The MAA strain showed strong virulence via mortality in rabbits and chickens. The prepared tuberculin of the MAA strain had similar potency compared to the MAA reference strain and standard tuberculin via a tuberculin skin test. Our studies suggested that this MAA strain tends to be a novel subtype, which might enrich the strain resource of avian tuberculosis.

  1. High pathogenicity and strong immunogenicity of a Chinese isolate of Eimeria magna Pérard, 1925.

    Science.gov (United States)

    Tao, Geru; Wang, Yunzhou; Li, Chao; Gu, Xiaolong; Cui, Ping; Fang, Sufang; Suo, Xun; Liu, Xianyong

    2017-06-01

    Coccidia infection of rabbits with one or several species of parasites of the genus Eimeria causes coccidiosis, a disease leading to huge economic losses in the rabbit industry. Eimeria magna, one of the causal agents of rabbit coccidiosis, was characterized as mildly pathogenic and moderately immunogenic in previous studies. In this study, we identified a Chinese isolate of E. magna by testing its biological features (oocyst morphology and size, prepatent time) and sequencing its internal transcribed spacer 1 (ITS-1) DNA fragment. This isolate is highly pathogenic; infection of rabbits with only 1×10 2 oocysts caused a 55% reduction in weight gain in 14days. In addition, immunization with 1×10 2 oocysts prevented body weight loss against re-infection with 5×10 4 oocysts, indicating the high immunogenicity of this isolate. Our study described the distinctive phenotype of the Chinese isolate of E. magna and contributed to the research of geographic variation of rabbit coccidia. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Growth inhibition of shrimp pathogens by isolated gastrointestinal microflora of Macrobrachium rosenbergii de Man

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    Seehanat, S.

    2005-02-01

    Full Text Available The useful bacteria which were isolated from the gastrointestinal tract of freshwater prawn (Macrobrachium rosenbergii de Man, cultivated in earthen pond at Maha Sarakham province, Thailand, consisted of 14 isolates of Bacillus (B1 – B14 and 18 isolates of Lactic acid bacteria (LA1 – LA18. The abilities of all isolated bacteria on growth inhibition of pathogenic bacteria (Escherichia coli, Bacillus cereus, Aeromonas hydrophila and Pseudomonas aeruginosa were studied by paperdisc plate method. The results showed that the Bacillus B2 and B5 were unable to inhibit the growth of all of the tested pathogens. Bacillus B1, B10 and B12 were capable of inhibiting the growth of 3 of 4 tested pathogen strains. Although all of the isolated lactic acid bacteria (LA1 –LA18 could not inhibit the E. coli growth, all of them could inhibit the growth of B. cereus. The isolated lactic acid bacteria which were capable of inhibiting the growth of 3 tested pathogen strains (excluded E. coli were LA12 , LA13 , LA14 , LA15 , LA16 , LA17 and LA18. In order to select the high potential strain of bacteria for using as probiotics, Bacillus B1 , B3 , B4 , B10 and B12 and lactic acid bacteria LA12 , LA13 , LA14 , LA15 , LA16 , LA17 and LA18 were tested for their growth abilities in various growth conditions. The tested growth conditions included various concentrations of the bile salt and salt (NaCl and various pH and temperatures. The results revealed that Bacillus B1 and B10 and lactic acid bacteria LA13 , LA16 and LA18 exhibited high potential for using as probiotics. The results of biochemical test for identification of these high potential strains showed that Bacillus B1 and B10 were possibly B. licheniformis and B. thuringiensis respectively. The lactic acid bacteria LA13 , LA16 and LA18 were possibly the same strain and belonged to the genus Pediococcus.

  3. Disruption of microbial biofilms by an extracellular protein isolated from epibiotic tropical marine strain of Bacillus licheniformis.

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    Devendra H Dusane

    Full Text Available BACKGROUND: Marine epibiotic bacteria produce bioactive compounds effective against microbial biofilms. The study examines antibiofilm ability of a protein obtained from a tropical marine strain of Bacillus licheniformis D1. METHODOLOGY/PRINCIPAL FINDINGS: B. licheniformis strain D1 isolated from the surface of green mussel, Perna viridis showed antimicrobial activity against pathogenic Candida albicans BH, Pseudomonas aeruginosa PAO1 and biofouling Bacillus pumilus TiO1 cultures. The antimicrobial activity was lost after treatment with trypsin and proteinase K. The protein was purified by ultrafiltration and size-exclusion chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE and matrix assisted laser desorption/ionization-time of flight (MALDI-TOF analysis revealed the antimicrobial agent to be a 14 kDa protein designated as BL-DZ1. The protein was stable at 75°C for 30 min and over a pH range of 3.0 to 11.0. The sequence alignment of the MALDI-fingerprint showed homology with the NCBI entry for a hypothetical protein (BL00275 derived from B. licheniformis ATCC 14580 with the accession number gi52082584. The protein showed minimum inhibitory concentration (MIC value of 1.6 µg/ml against C. albicans. Against both P. aeruginosa and B. pumilus the MIC was 3.12 µg/ml. The protein inhibited microbial growth, decreased biofilm formation and dispersed pre-formed biofilms of the representative cultures in polystyrene microtiter plates and on glass surfaces. CONCLUSION/SIGNIFICANCE: We isolated a protein from a tropical marine strain of B. licheniformis, assigned a function to the hypothetical protein entry in the NCBI database and described its application as a potential antibiofilm agent.

  4. Disruption of Microbial Biofilms by an Extracellular Protein Isolated from Epibiotic Tropical Marine Strain of Bacillus licheniformis

    Science.gov (United States)

    Dusane, Devendra H.; Damare, Samir R.; Nancharaiah, Yarlagadda V.; Ramaiah, N.; Venugopalan, Vayalam P.; Kumar, Ameeta Ravi; Zinjarde, Smita S.

    2013-01-01

    Background Marine epibiotic bacteria produce bioactive compounds effective against microbial biofilms. The study examines antibiofilm ability of a protein obtained from a tropical marine strain of Bacillus licheniformis D1. Methodology/Principal Findings B. licheniformis strain D1 isolated from the surface of green mussel, Perna viridis showed antimicrobial activity against pathogenic Candida albicans BH, Pseudomonas aeruginosa PAO1 and biofouling Bacillus pumilus TiO1 cultures. The antimicrobial activity was lost after treatment with trypsin and proteinase K. The protein was purified by ultrafiltration and size-exclusion chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis revealed the antimicrobial agent to be a 14 kDa protein designated as BL-DZ1. The protein was stable at 75°C for 30 min and over a pH range of 3.0 to 11.0. The sequence alignment of the MALDI-fingerprint showed homology with the NCBI entry for a hypothetical protein (BL00275) derived from B. licheniformis ATCC 14580 with the accession number gi52082584. The protein showed minimum inhibitory concentration (MIC) value of 1.6 µg/ml against C. albicans. Against both P. aeruginosa and B. pumilus the MIC was 3.12 µg/ml. The protein inhibited microbial growth, decreased biofilm formation and dispersed pre-formed biofilms of the representative cultures in polystyrene microtiter plates and on glass surfaces. Conclusion/Significance We isolated a protein from a tropical marine strain of B. licheniformis, assigned a function to the hypothetical protein entry in the NCBI database and described its application as a potential antibiofilm agent. PMID:23691235

  5. Antibiotic resistance of microbial contaminations isolated from husbandry animals and foodstuffs

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    Lukáš Hleba

    2014-05-01

    Full Text Available In this paper the antibiotic resistance of microbial contaminations isolated from husbandry animals and foodstuffs were investigated. Microorganisms isolated from animals and foodstuffs were contaminations of selective media as MacConkey agar for Enterobacteriaceae genera and MRS agar for lactobacilli strains. Microorganisms were isolated and puryfied by agar four ways streak plate method. Identification of isolated microorganisms was done by mass-spectrometry method in MALDI-TOF MS Biotyper. For investigation of antibiotic resistance disc diffusion method by EUCAST was used. In this study Gram-negative and Gram-positive bacteria were identified. The most resistant or multi-resistant bacteria as Pseudomonas aeruginosa, Acinetobacter lwoffi, Lysinibacillus sphaericus, Staphylococcus aureus and Staphylococcus epidermis were determined. Other identified microorganisms were resistant to one antibiotic or not at all.

  6. Dynamic Evolution of Pathogenicity Revealed by Sequencing and Comparative Genomics of 19 Pseudomonas syringae Isolates

    Science.gov (United States)

    Romanchuk, Artur; Chang, Jeff H.; Mukhtar, M. Shahid; Cherkis, Karen; Roach, Jeff; Grant, Sarah R.; Jones, Corbin D.; Dangl, Jeffery L.

    2011-01-01

    Closely related pathogens may differ dramatically in host range, but the molecular, genetic, and evolutionary basis for these differences remains unclear. In many Gram- negative bacteria, including the phytopathogen Pseudomonas syringae, type III effectors (TTEs) are essential for pathogenicity, instrumental in structuring host range, and exhibit wide diversity between strains. To capture the dynamic nature of virulence gene repertoires across P. syringae, we screened 11 diverse strains for novel TTE families and coupled this nearly saturating screen with the sequencing and assembly of 14 phylogenetically diverse isolates from a broad collection of diseased host plants. TTE repertoires vary dramatically in size and content across all P. syringae clades; surprisingly few TTEs are conserved and present in all strains. Those that are likely provide basal requirements for pathogenicity. We demonstrate that functional divergence within one conserved locus, hopM1, leads to dramatic differences in pathogenicity, and we demonstrate that phylogenetics-informed mutagenesis can be used to identify functionally critical residues of TTEs. The dynamism of the TTE repertoire is mirrored by diversity in pathways affecting the synthesis of secreted phytotoxins, highlighting the likely role of both types of virulence factors in determination of host range. We used these 14 draft genome sequences, plus five additional genome sequences previously reported, to identify the core genome for P. syringae and we compared this core to that of two closely related non-pathogenic pseudomonad species. These data revealed the recent acquisition of a 1 Mb megaplasmid by a sub-clade of cucumber pathogens. This megaplasmid encodes a type IV secretion system and a diverse set of unknown proteins, which dramatically increases both the genomic content of these strains and the pan-genome of the species. PMID:21799664

  7. Differences in pathogenicity of three animal isolates of Mycobacterium species in a mouse model.

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    Haodi Dong

    Full Text Available Animal mycobacterioses are among the most important zoonoses worldwide. These are generally caused by either Mycobacterium tuberculosis (MTB, M. bovis (MBO or M. avium (MAV. To test the hypothesis that different species of pathogenic mycobacteria isolated from varied anatomic locations or animal species differ in virulence and pathogenicity, we performed experiments with three mycobacteria strains (NTSE-3(MTB, NTSE-4(MBO and NTSE-5 (MAV obtained from animal species. Spoligotyping analysis was used to confirm both MTB and MBO strains while the MAV strain was confirmed by 16s rDNA sequencing. BALB/c mice were intranasally infected with the three strains at low and high CFU doses to evaluate variations in pathogenicity. Clinical and pathological parameters were assessed. Infected mice were euthanized at 80 days post-inoculation (dpi. Measures of lung and body weights indicated that the MBO infected group had higher mortality, more weight loss, higher bacterial burden and more severe lesions in lungs than the other two groups. Cytokine profiles showed higher levels of TNF-α for MBO versus MTB, while MAV had the highest amounts of IFN-β in vitro and in vivo. In vitro levels of other cytokines such as IL-1β, IL-10, IL-12, IL-17, and IFN-β showed that Th1 cells had the strongest response in MBO infected mice and that Th2 cells were inhibited. We found that the level of virulence among the three isolates decreased in the following order MBO>MTB>MAV.

  8. Isolation and characterization of highly pathogenic avian influenza virus subtype H5N1 from donkeys

    Science.gov (United States)

    2010-01-01

    Background The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences. Methods Nasal swabs were collected from donkeys suffered from respiratory distress. The virus was isolated from the pooled nasal swabs in specific pathogen free embryonated chicken eggs (SPF-ECE). Reverse transcriptase polymerase chain reaction (RT-PCR) and sequencing of both haemagglutingin and neuraminidase were performed. H5 seroconversion was screened using haemagglutination inhibition (HI) assay on 105 donkey serum samples. Results We demonstrated that H5N1 jumped from poultry to another mammalian host; donkeys. Phylogenetic analysis showed that the virus clustered within the lineage of H5N1 from Egypt, closely related to 2009 isolates. It harboured few genetic changes compared to the closely related viruses from avian and humans. The neuraminidase lacks oseltamivir resistant mutations. Interestingly, HI screening for antibodies to H5 haemagglutinins in donkeys revealed high exposure rate. Conclusions These findings extend the host range of the H5N1 influenza virus, possess implications for influenza virus epidemiology and highlight the need for the systematic surveillance of H5N1 in animals in the vicinity of backyard poultry units especially in endemic areas. PMID:20398268

  9. Isolation and characterization of highly pathogenic avian influenza virus subtype H5N1 from donkeys

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    Abdel-Ghany Ahmad E

    2010-04-01

    Full Text Available Abstract Background The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences. Methods Nasal swabs were collected from donkeys suffered from respiratory distress. The virus was isolated from the pooled nasal swabs in specific pathogen free embryonated chicken eggs (SPF-ECE. Reverse transcriptase polymerase chain reaction (RT-PCR and sequencing of both haemagglutingin and neuraminidase were performed. H5 seroconversion was screened using haemagglutination inhibition (HI assay on 105 donkey serum samples. Results We demonstrated that H5N1 jumped from poultry to another mammalian host; donkeys. Phylogenetic analysis showed that the virus clustered within the lineage of H5N1 from Egypt, closely related to 2009 isolates. It harboured few genetic changes compared to the closely related viruses from avian and humans. The neuraminidase lacks oseltamivir resistant mutations. Interestingly, HI screening for antibodies to H5 haemagglutinins in donkeys revealed high exposure rate. Conclusions These findings extend the host range of the H5N1 influenza virus, possess implications for influenza virus epidemiology and highlight the need for the systematic surveillance of H5N1 in animals in the vicinity of backyard poultry units especially in endemic areas.

  10. Potential for Combined Biocontrol Activity against Fungal Fish and Plant Pathogens by Bacterial Isolates from a Model Aquaponic System

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    Ivaylo Sirakov

    2016-11-01

    Full Text Available One of the main challenges in aquaponics is disease control. One possible solution for this is biological control with organisms exerting inhibitory effects on fish and plant pathogens. The aim of this study was to examine the potential of isolating microorganisms that exert an inhibitory effect on both plant and fish pathogens from an established aquaponic system. We obtained 924 isolates on selective King’s B agar and 101 isolates on MRS agar from different compartments of a model aquaponic system and tested them for antagonism against the plant pathogen Pythium ultimum and fish pathogen Saprolegnia parasitica. Overall, 42 isolates were able to inhibit both fungi. Although not yet tested in vivo, these findings open new options for the implementation of biological control of diseases in aquaponics, where plants and fish are cultivated in the same water recirculating system.

  11. Synergistic antibacterial action of β-sitosterol-D-glucopyranoside isolated from Desmostachya bipinnata leaves with antibiotics against common human pathogens

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    Shankar Subramaniam

    Full Text Available Desmostachya bipinnata (L. Stapf, Poaceae, or Kusha in Sanskrit, is a sacred grass used extensively in Indian Vedic practices. It is well known for its medicinal value and is used in traditional Indian medicine to treat microbial infection in combination with other herbs. An effort has been made to isolate and characterize the bioactive compounds from the hydroalcoholic extract of D. bipinnata through bioassay guided fractionation, column chromatography. Their individual or combined antimicrobial properties were determined by the Resazurin Microtitre Assay, the checkerboard assay in combination with antibiotics, and by time kill curve analysis. β-Sitosterol-D-glucopyranoside was the bioactive compound identified to have the best antimicrobial activity (MIC 6-50 µg/ml and it works synergistically with most antibiotics, especially with ciprofloxacin. Time kill curves showed that BS kills most of the pathogens within 5-10 h. To our knowledge at its best, this is the first time report of antibacterial synergy of β-sitosterol-D-glucopyranoside from D. bipinnata.

  12. MICROBIAL PROFILE AND ANTIBIOTIC SUSCEPTIBILITY PATTERNS OF PATHOGENS CAUSING VENTILATOR- ASSOCIATED PNEUMONIA AT INTENSIVE CARE UNIT, SESTRE MILOSRDNICE UNIVERSITY HOSPITAL CENTER, ZAGREB, CROATIA.

    Science.gov (United States)

    Turković, Tihana Magdić; Grginić, Ana Gverić; Cucujić, Branka Đuras; Gašpar, Božena; Širanović, Mladen; Perić, Mladen

    2015-06-01

    Ventilator-associated pneumonia (VAP) is very common in many intensive care Units, but there are still many uncertainties about VAP, especially about the choice of initial empiric antibiotics. The incidence of specific pathogens with different susceptibility patterns causing VAP varies from hospital to hospital. This is the reason why empiric initial antibiotic treatment for VAP should be based not only on general guidelines (that recommend therapy according to the presence of risk factors for multidrug-resistant bacteria), but also on up-to-date information on local epidemiology. The aim of this study was to determine the microbial profile of pathogens causing VAP and their antibiotic susceptibility patterns. The study was conducted in the 15-bed surgical and neurosurgical Intensive Care Unit, Department of Anesthesiology and Intensive Care, Sestre milosrdnice University Hospital Center, Zagreb, Croatia. Retrospective data were collected from September 2009 to March 2013. All patients that developed VAP during the study period were eligible for the study. According to study results, the incidence of VAP was 29.4%. The most commonly isolated bacterium was Staphylococcus aureus (21.1%), followed by Pseudomonas aeruginosa (19.0%) and Acinetobacter species (13.6%). All Staphylococcus aureus isolates were susceptible to vancomycin and linezolid. Pseudomonas aeruginosa showed 100% susceptibility to cefepime and very high susceptibility to pip'eracillin-tazobactam (96%), ceftazidime (93%) and ciprofloxacin (89%). Ampicillin-sulbactam was highly effective for Acinetobacter species, showing resistance in only 8% of isolates. In conclusion, according to study data, appropriate empiric antibiotic therapy for patients with VAP without risk factors for multidrug-resistant bacteria is ceftriaxone and for patients with risk factors for multidrug-resistant bacteria ampicillin-sulbactam plus cefepime plus vancomycin or linezolid.

  13. Host range of an NPV and a GV isolated from the common cutworm, Agrotis segetum: pathogenicity within the cutworm complex

    NARCIS (Netherlands)

    Bourner, T.C.; Cory, J.S.

    2004-01-01

    The term cutworm covers a range of species with a similar life history that can be very damaging pests on a wide range of crops. Attacks by cutworms are often made up of more than one species; thus, the most cost effective microbial control agent needs to be pathogenic for multiple species within

  14. Cytotoxic and pathogenic properties of Klebsiella oxytoca isolated from laboratory animals.

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    Alison Darby

    Full Text Available Klebsiella oxytoca is an opportunistic pathogen implicated in various clinical diseases in animals and humans. Studies suggest that in humans K. oxytoca exerts its pathogenicity in part through a cytotoxin. However, cytotoxin production in animal isolates of K. oxytoca and its pathogenic properties have not been characterized. Furthermore, neither the identity of the toxin nor a complete repertoire of genes involved in K. oxytoca pathogenesis have been fully elucidated. Here, we showed that several animal isolates of K. oxytoca, including the clinical isolates, produced secreted products in bacterial culture supernatant that display cytotoxicity on HEp-2 and HeLa cells, indicating the ability to produce cytotoxin. Cytotoxin production appears to be regulated by the environment, and soy based product was found to have a strong toxin induction property. The toxin was identified, by liquid chromatography-mass spectrometry and NMR spectroscopy, as low molecular weight heat labile benzodiazepine, tilivalline, previously shown to cause cytotoxicity in several cell lines, including mouse L1210 leukemic cells. Genome sequencing and analyses of a cytotoxin positive K. oxytoca strain isolated from an abscess of a mouse, identified genes previously shown to promote pathogenesis in other enteric bacterial pathogens including ecotin, several genes encoding for type IV and type VI secretion systems, and proteins that show sequence similarity to known bacterial toxins including cholera toxin. To our knowledge, these results demonstrate for the first time, that animal isolates of K. oxytoca, produces a cytotoxin, and that cytotoxin production is under strict environmental regulation. We also confirmed tilivalline as the cytotoxin present in animal K. oxytoca strains. These findings, along with the discovery of a repertoire of genes with virulence potential, provide important insights into the pathogenesis of K. oxytoca. As a novel diagnostic tool, tilivalline

  15. Frequency Of Isolation Of Salmonella From Commercial Poultry Feeds And Their Anti-Microbial Resistance Profiles, Imo State, Nigeria

    OpenAIRE

    Okoli IC; Ndujihe GE; Ogbuewu IP

    2006-01-01

    This study was conducted to determine the frequency of isolation of salmonella and their microbial resistance profiles across different commercial poultry feeds sold in Imo State, Nigeria. Thirty-six bulk feed samples were colleted from 154 bag across different feed types and brands which included Guinea (GF), Top (TF), Vital (VF), Extra (EF), Animal care (AF) and livestock (LF) feeds. The salmonella isolated were tested against 14 anti-microbial drugs using the disc diffusion method. Bacteri...

  16. Pathogenicity of Bacillus thuringiensis isolated from two species of Acromyrmex (Hymenoptera, Formicidae

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    L. M. N. Pinto

    Full Text Available The control of Acromyrmex leaf-cutting ants is necessary due to the severe damage they cause to diverse crops. A possibility was to control them using the bacterium Bacillus thuringiensis (Bt that characteristically produces insecticidal crystal proteins (ICPs. The ICPs have been effective in controlling lepidopterans, dipterans, and coleopterans, but their action against hymenopterans is unknown. This paper describes an attempt to isolate Bt from ants of two Acromyrmex species, to evaluate its pathogenicity towards these ants, and to test isolates by PCR. Bacterial isolates of Bt obtained from A. crassispinus and A. lundi have been assayed against A. lundi in the laboratory. The bioassays were carried out in BOD at 25°C, with a 12-hour photoperiod, until the seventh day after treatment. The Bt isolates obtained were submitted to total DNA extraction and tested by PCR with primers specific to cry genes. The results showed Bt presence in 40% of the assessed samples. The data from the in vivo assays showed a mortality rate higher than 50% in the target population, with the Bt HA48 isolate causing 100% of corrected mortality. The PCR results of Bt isolates showed a magnification of DNA fragments relative to cry1 genes in 22% of the isolates, and cry9 in 67%. Cry2, cry3, cry7, and cry8 genes were not detected in the tested samples, and 22% had no magnified DNA fragments corresponding to the assessed cry genes. The results are promising not only regarding allele identification in new isolates, but also fort the assays aimed at determining the Bt HA48 LC50's, which can eventually be applied in controlling of Acromyrmex leaf-cutting ants.

  17. Isolation of bacterial fish pathogen Aeromonas hydrophila and therapeutic effects of medicinal plants on its invasion

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    Md. Tareq-Uz-Zaman

    2014-04-01

    Full Text Available Aeromonas hydrophila, a bacterial pathogen, was isolated form Pangasius hypophthalmus. For pathogenicity test, different doses were injected intramuscularly in Barbonymus gonionotus. Crude extracts were prepared from various parts Azadirachta indica, Curcuma longa, C. zedoaria, and Callotropis gigentia and applied to B. gonionotus for 7 days. Bath treatment was done up to their tolerance level and well ventilation was confirmed for aeration and 50% water was exchanged daily. Minimum inhibitory dose was detected as 7 mg/ml. High inhibitory effect was observed in case of A. indica and mixed extract of A. indica and C. gigentia. Both A. indica and C. gigentia showed the best result with 90-95% recovery of infected fish at a dose of 7 mg/l. C. zedoaria showed moderate to weak effect with 50-60% recovery at the same dose. The present study showed that medicinal plants would be an effective control measure against A. hydrophila.

  18. Quantification of pathogenic microorganisms and microbial indicators in three wastewater reclamation and managed aquifer recharge facilities in Europe.

    Science.gov (United States)

    Levantesi, Caterina; La Mantia, Rosanna; Masciopinto, Costantino; Böckelmann, Uta; Ayuso-Gabella, M Neus; Salgot, Miquel; Tandoi, Valter; Van Houtte, Emmanuel; Wintgens, Thomas; Grohmann, Elisabeth

    2010-10-01

    Managed Aquifer Recharge (MAR) is becoming an attractive option for water storage in water reuse processes as it provides an additional treatment barrier to improve recharged water quality and buffers seasonal variations of water supply and demand. To achieve a better understanding about the level of pathogenic microorganisms and their relation with microbial indicators in these systems, five waterborne pathogens and four microbial indicators were monitored over one year in three European MAR sites operated with reclaimed wastewater. Giardia and Cryptosporidium (oo)cysts were found in 63.2 and 36.7% of the samples respectively. Salmonella spp. and helminth eggs were more rarely detected (16.3% and 12.5% of the samples respectively) and Campylobacter cells were only found in 2% of samples. At the Belgian site advanced tertiary treatment technology prior to soil aquifer treatment (SAT) produced effluent of drinking water quality, with no presence of the analysed pathogens. At the Spanish and Italian sites amelioration of microbiological water quality was observed between the MAR injectant and the recovered water. In particular Giardia levels decreased from 0.24-6.14 cysts/L to 0-0.01 cysts/L and from 0.4-6.2 cysts/L to 0-0.07 cysts/L in the Spanish and Italian sites respectively. Salmonella gene copies and Giardia cysts were however found in the water for final use and/or the recovered groundwater water at the two sites. Significant positive Spearman correlations (p<0.05, r(s) range: 0.45-0.95) were obtained, in all the three sites, between Giardia cysts and the most resistant microbial markers, Clostridium spores and bacteriophages. Copyright 2010 Elsevier B.V. All rights reserved.

  19. Rearing Water Treatment Induces Microbial Selection Influencing the Microbiota and Pathogen Associated Transcripts of Cod (Gadus morhua Larvae

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    Ragnhild I. Vestrum

    2018-05-01

    Full Text Available We have previously shown that K-selection and microbial stability in the rearing water increases survival and growth of Atlantic cod (Gadus morhua larvae, and that recirculating aquaculture systems (RAS are compatible with this. Here, we have assessed how water treatment influenced the larval microbiota and host responses at the gene expression level. Cod larvae were reared with two different rearing water systems: a RAS and a flow-through system (FTS. The water microbiota was examined using a 16S rDNA PCR/DGGE strategy. RNA extracted from larvae at 8, 13, and 17 days post hatching was used for microbiota and microarray gene expression analysis. Bacterial cDNA was synthesized and used for 16S rRNA amplicon 454 pyrosequencing of larval microbiota. Both water and larval microbiota differed significantly between the systems, and the larval microbiota appeared to become more dissimilar between systems with time. In total 4 phyla were identified for all larvae: Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. The most profound difference in larval microbiota was a high abundance of Arcobacter (Epsilonproteobacteria in FTS larvae (34 ± 9% of total reads. Arcobacter includes several species that are known pathogens for humans and animals. Cod larval transcriptome responses were investigated using an oligonucleotide gene expression microarray covering approximately 24,000 genes. Interestingly, FTS larvae transcriptional profiles revealed an overrepresentation of upregulated transcripts associated with responses to pathogens and infections, such as c1ql3-like, pglyrp-2-like and zg16, compared to RAS larvae. In conclusion, distinct water treatment systems induced differences in the larval microbiota. FTS larvae showed up-regulation of transcripts associated with responses to microbial stress. These results are consistent with the hypothesis that RAS promotes K-selection and microbial stability by maintaining a microbial load close to the

  20. Genome characterization, antigenicity and pathogenicity of a novel infectious bronchitis virus type isolated from south China.

    Science.gov (United States)

    Jiang, Lei; Zhao, Wenjun; Han, Zongxi; Chen, Yuqiu; Zhao, Yan; Sun, Junfeng; Li, Huixin; Shao, Yuhao; Liu, Liangliang; Liu, Shengwang

    2017-10-01

    In 2014, three infectious bronchitis virus (IBV) strains, designated as γCoV/ck/China/I0111/14, γCoV/ck/China/I0114/14 and γCoV/ck/China/I0118/14, were isolated and identified from chickens suspected to be infected with IBV in Guangxi province, China. Based upon data arising from S1 sequence and phylogenetic analyses, the three IBV isolates were genetically different from other known IBV types, which represented a novel genotype (GI-29). Virus cross-neutralization tests, using γCoV/ck/China/I0111/14 as a representative, showed that genotype GI-29 was antigenically different from all other known IBV types, thus representing a novel serotype. Complete genomic analysis showed that GI-29 type viruses were closely related to and might originate from a GX-YL5-like virus by accumulation of substitutions in multiple genes. These GI-29 viral genomes are still evolving and diverging, particularly in the 3' region, although we cannot rule out the possibility of recombination events occurring. For isolate γCoV/ck/China/I0114/14, we found that recombination events had occurred between nsps 2 and 3 in gene 1 which led to the introduction of a 4/91 gene fragment into the γCoV/ck/China/I0114/14 viral genome. In addition, we found that the GI-29 type γCoV/ck/China/I0111/14 isolate was a nephropathogenic strain and high pathogenic to 1-day-old specific pathogen-free (SPF) chickens although cystic oviducts were not observed in the surviving layer chickens challenged with γCoV/ck/China/I0111/14 isolate. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Pathogenicity of Salmonella Strains Isolated from Egg Shells and the Layer Farm Environment in Australia

    Science.gov (United States)

    McWhorter, Andrea R.; Davos, Dianne

    2014-01-01

    In Australia, the egg industry is periodically implicated during outbreaks of Salmonella food poisoning. Salmonella enterica serovar Typhimurium and other nontyphoidal Salmonella spp., in particular, are a major concern for Australian public health. Several definitive types of Salmonella Typhimurium strains, but primarily Salmonella Typhimurium definitive type 9 (DT9), have been frequently reported during egg-related food poisoning outbreaks in Australia. The aim of the present study was to generate a pathogenicity profile of nontyphoidal Salmonella isolates obtained from Australian egg farms. To achieve this, we assessed the capacity of Salmonella isolates to cause gastrointestinal disease using both in vitro and in vivo model systems. Data from in vitro experiments demonstrated that the invasion capacity of Salmonella serovars cultured to stationary phase (liquid phase) in LB medium was between 90- and 300-fold higher than bacterial suspensions in normal saline (cultured in solid phase). During the in vivo infection trial, clinical signs of infection and mortality were observed only for mice infected with either 103 or 105 CFU of S. Typhimurium DT9. No mortality was observed for mice infected with Salmonella serovars with medium or low invasive capacity in Caco-2 cells. Pathogenicity gene profiles were also generated for all serovars included in this study. The majority of serovars tested were positive for selected virulence genes. No relationship between the presence or absence of virulence genes by PCR and either in vitro invasive capacity or in vivo pathogenicity was detected. Our data expand the knowledge of strain-to-strain variation in the pathogenicity of Australian egg industry-related Salmonella spp. PMID:25362057

  2. Isolation and in vitro cultivation of the aphid pathogenic fungus Entomophthora planchoniana.

    Science.gov (United States)

    Freimoser, F M; Jensen, A B; Tuor, U; Aebi, M; Eilenberg, J

    2001-12-01

    Entomophthora planchoniana is an important fungal pathogen of aphids. Although Entomophthora chromaphidis has been considered a synonym for E. planchoniana, the two species are now separated, and E. planchoniana is reported not to grow in vitro. In this paper, we describe for the first time the isolation and cultivation of this species. Entomophthora planchoniana was isolated from a population of Ovatus crataegarius (Homoptera, Aphididae), which was infected by E. planchoniana only. The isolates did not sporulate, but the sequence of the small subunit rDNA and the restriction fragment length polymorphism patterns of the first part of the large subunit rDNA and the ITS II region confirm that the isolates were E. planchoniana. The isolated fungus grew in a medium consisting of Grace's insect cell culture medium supplemented with lactalbumin hydrolysate, yeastolate, and 10% fetal bovine serum or in GLEN medium with 10% fetal bovine serum. Vegetative cells of E. planchoniana were long and club-shaped and did not stain with Calcofluor, thus suggesting that they were protoplasts.

  3. Microbial Indicators, Pathogens, and Antibiotic Resistance in Groundwater Impacted by Animal Farming: Field Scale to Basin Scale

    Science.gov (United States)

    Harter, T.; Li, X.; Atwill, E. R.; Packman, A. I.

    2015-12-01

    Several surveys of microbial indicators and pathogens were conducted to determine the impact of confined animal farming operations (CAFOs) on shallow, local, and regional groundwater quality in the Central Valley aquifer system, California. The aquifer system consists of highly heterogeneous, alluvial, unconsolidated coarse- to fine-grained sediments and is among the largest aquifers in the U.S.. Overlying landuse includes 3 million ha of irrigated agriculture and 1.7 million mature dairy cows in nearly 1,500 CAFOs. A multi-scale survey of water-borne indicator pathogens (Enterococcus spp. and generic E. coli) and of three water-borne pathogens (Campylobacter, Salmonella, and E. coli O157:H7) was conducted at five different spatial scales, increasing with distance from animal sources of these enteric microbial organisms: moist surfaces within individual CAFO sub-systems (calf-hutches, heifer corrals, mature cow stalls, hospital barn etc.), first encountered (shallow) groundwater immediately below these sub-systems, production aquifer below CAFOs, production aquifer near CAFOs, and production aquifer away from CAFOs. Where found, indicator pathogens were tested for antibiotic resistance. Hundreds of samples were collected at each scale: continuously during irrigation events and seasonally over a multi-year period at the three smaller site-scales; and in a one-time survey at the two larger, regional scales. All three pathogens were frequently detected in moist surface samples across CAFO sub-systems, albeit at concentrations several orders of magnitude lower than enteric indicators. Two of the three pathogens (but not Campylobacter) were also detected in first encountered groundwater, at 3-9 m below ground surface, in 1% of samples. No pathogens were found at the production aquifer scales. Generic E. coli was detected in ¼ of first encountered groundwater samples, and in 4% of production aquifer samples, while Enterococcus spp. was ubiquitously present across the

  4. Antagonistic effect of Pseudomonas aeruginosa isolates from various ecological niches on Vibrio species pathogenic to crustaceans

    Institute of Scientific and Technical Information of China (English)

    Prabhakaran Priyaja; Puthumana Jayesh; Neil Scolastin Correya; Balachandran Sreelakshmi; Naduthalmuriparambil S Sudheer; Rosamma Philip; Isaac Sarogeni Bright Singh

    2014-01-01

    Objective: To abrogate pathogenic vibrios in aquaculture by testing the potential of Pseudomonas isolates from fresh water, brackish and marine environments as probiotics.Methods:Antagonistic activity of the compound against 7 Vibrio spp. was performed. Influence of salinity on the production of pyocyanin and the toxicity was done through the compound using brine shrimp lethality assay. Molecular characterization was performed to confirm that the isolates werePseudomonas aeruginosa. Results: Salinity was found to regulate the levels of pyocyanin production, with 5-10 g/L as the optimum. All Pseudomonas isolates grew at salinities ranging from 5 to 70 g/L. Isolates of marine origin produced detectable levels of pyocyanin up to 45 g/L salinity. Brackish and freshwater isolates ceased to produce pyocyanin at salinities above 30 g/L and 20 g/L, respectively. Culture supernatants of all 5 Pseudomonas isolates possessed the ability to restrict the growth of Vibrio spp. and maximum antagonistic effect on Vibrio harveyi was obtained when they were grown at salinities of 5 to 10 g/L. The marine isolate MCCB117, even when grown at a salinity of 45 g/L possessed the ability to inhibit Vibrio spp.Conclusions:Purification and structural elucidation of antagonistic compound were carried out. ideal for application in freshwater, MCCB102 and MCCB103 in brackish water and MCCB117 and The present investigation showed that Pseudomonas aeruginosa MCCB119 would be MCCB118 in marine aquaculture systems as putative probiotics in the management of vibrios.

  5. Antagonistic effect of Pseudomonas aeruginosa isolates from various ecological niches on Vibrio species pathogenic to crustaceans

    Directory of Open Access Journals (Sweden)

    Prabhakaran Priyaja

    2014-01-01

    Full Text Available Objective: To abrogate pathogenic vibrios in aquaculture by testing the potential of Pseudomonas isolates from fresh water, brackish and marine environments as probiotics. Methods: Purification and structural elucidation of antagonistic compound were carried out. Antagonistic activity of the compound against 7 Vibrio spp. was performed. Influence of salinity on the production of pyocyanin and the toxicity was done through the compound using brine shrimp lethality assay. Molecular characterization was performed to confirm that the isolates were Pseudomonas aeruginosa. Results: Salinity was found to regulate the levels of pyocyanin production, with 5-10 g/L as the optimum. All Pseudomonas isolates grew at salinities ranging from 5 to 70 g/L. Isolates of marine origin produced detectable levels of pyocyanin up to 45 g/L salinity. Brackish and freshwater isolates ceased to produce pyocyanin at salinities above 30 g/L and 20 g/L, respectively. Culture supernatants of all 5 Pseudomonas isolates possessed the ability to restrict the growth of Vibrio spp. and maximum antagonistic effect on Vibrio harveyi was obtained when they were grown at salinities of 5 to 10 g/L. The marine isolate MCCB117, even when grown at a salinity of 45 g/L possessed the ability to inhibit Vibrio spp. Conclusions: The present investigation showed that Pseudomonas aeruginosa MCCB119 would be ideal for application in freshwater, MCCB102 and MCCB103 in brackish water and MCCB117 and MCCB118 in marine aquaculture systems as putative probiotics in the management of vibrios.

  6. Methylobacteria isolated from bryophytes and the 2-fold description of the same microbial species

    OpenAIRE

    Schauer, S.; Kutschera, U.

    2013-01-01

    On the surface of healthy land plants (embryophytes), numerous non-pathogenic bacteria have been discovered and described. Among these epiphytic microbes, pink-pigmented facultative methylotrophic microbes of the genus Methylobacterium are of special significance, because these microorganisms consume methanol emitted via the stomatal pores and secrete growth-promoting phytohormones. Methylobacterium funariae, Schauer and Kutschera 2011, a species isolated in our lab from the common cord moss,...

  7. Microbial enhanced heavy crude oil recovery through biodegradation using bacterial isolates from an Omani oil field.

    Science.gov (United States)

    Al-Sayegh, Abdullah; Al-Wahaibi, Yahya; Al-Bahry, Saif; Elshafie, Abdulkadir; Al-Bemani, Ali; Joshi, Sanket

    2015-09-16

    Biodegradation is a cheap and environmentally friendly process that could breakdown and utilizes heavy crude oil (HCO) resources. Numerous bacteria are able to grow using hydrocarbons as a carbon source; however, bacteria that are able to grow using HCO hydrocarbons are limited. In this study, HCO degrading bacteria were isolated from an Omani heavy crude oil field. They were then identified and assessed for their biodegradation and biotransformation abilities under aerobic and anaerobic conditions. Bacteria were grown in five different minimum salts media. The isolates were identified by MALDI biotyper and 16S rRNA sequencing. The nucleotide sequences were submitted to GenBank (NCBI) database. The bacteria were identified as Bacillus subtilis and B. licheniformis. To assess microbial growth and biodegradation of HCO by well-assay on agar plates, samples were collected at different intervals. The HCO biodegradation and biotransformation were determined using GC-FID, which showed direct correlation of microbial growth with an increased biotransformation of light hydrocarbons (C12 and C14). Among the isolates, B. licheniformis AS5 was the most efficient isolate in biodegradation and biotransformation of the HCO. Therefore, isolate AS5 was used for heavy crude oil recovery experiments, in core flooding experiments using Berea core plugs, where an additional 16 % of oil initially in place was recovered. This is the first report from Oman for bacteria isolated from an oil field that were able to degrade and transform HCO to lighter components, illustrating the potential use in HCO recovery. The data suggested that biodegradation and biotransformation processes may lead to additional oil recovery from heavy oil fields, if bacteria are grown in suitable medium under optimum growth conditions.

  8. Inhibitory effect of Lactobacillus rhamnosus on pathogenic bacteria isolated from women with bacterial vaginosis

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    Gita Eslami

    2014-06-01

    Full Text Available Background: Considering the high prevalence of bacterial vaginosis and its association with urinary tract infection in women and treatment of gynecologic problems occur when a high recurrence of bacterial vaginosis is often treated with antibiotics. The purpose of this study is to investigate the inhibitory effect of Lactobacillus rhamnosus on pathogenic bacteria isolated from women with bacterial vaginosis, respectively.Materials and Methods: 96 samples from women with bacterial vaginosis discharge referred to health centers dependent Shahid Beheshti University in 91-92 were taken by a gynecologist with a dacron swab and put in sterile tubes containing TSB broth and Thioglycollate broth and were immediately sent to the lab location in cold chain for the next stages of investigation. From Thioglycollate and TSB medium was cultured on blood agar and EMB and Palkam and Differential diagnosis environments, and then incubated for 24 h at 37°C. Strains of Lactobacillus rhamnosus were cultured in MRSA environment and were transfered to the lab. After purification of pathogenic bacteria, MIC methods and antibiogram, Lactobacillus rhamnosus inhibitory effect on pathogenic bacteria is checked. Statistical analysis was done by SPSS software v.16.Results: The results of this study show the inhibitory effect of Lactobacillus rhamnosus on some pathogenic bacteria that cause bacterial vaginosis, including Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus agalactiae, Entrococcus, Listeria monocytogenes and E.Coli. Microscopic examination of stained smears of the large number of Lactobacillus and pathogenic bacteria showed reduced. The prevalence of abnormal vaginal discharge, history of drug use means of preventing pregnancy and douching, respectively, 61%, 55%, 42% and 13% respectively. Significant difference was observed between the use and non-use of IUD in women with bacterial vaginosis infection

  9. Are pathogenic bacteria just looking for food? Metabolism and microbial pathogenesis

    Science.gov (United States)

    Rohmer, Laurence; Hocquet, Didier; Miller, Samuel I.

    2011-01-01

    It is interesting to speculate that the evolutionary drive of microbes to develop pathogenic characteristics was to access the nutrient resources that animals provided. Environments in animals that pathogens colonize have also driven the evolution of new bacterial characteristics to maximize these new nutritional opportunities. This review focuses on genomic and functional aspects of pathogen metabolism that allow efficient utilization of nutrient resources provided by animals. Similar to genes encoding specific virulence traits, some genes encoding metabolic functions have been horizontally acquired by pathogens to provide a selective advantage in host tissues. Selective advantage in host tissues can also be gained in some circumstances by loss of function due to mutations that alter metabolic capabilities. Greater understanding of bacterial metabolism within host tissues should be important for increased understanding of host-pathogen interactions and the development of future therapeutic strategies. PMID:21600774

  10. Whole genome sequencing of the monomorphic pathogen Mycobacterium bovis reveals local differentiation of cattle clinical isolates.

    Science.gov (United States)

    Lasserre, Moira; Fresia, Pablo; Greif, Gonzalo; Iraola, Gregorio; Castro-Ramos, Miguel; Juambeltz, Arturo; Nuñez, Álvaro; Naya, Hugo; Robello, Carlos; Berná, Luisa

    2018-01-02

    Bovine tuberculosis (bTB) poses serious risks to animal welfare and economy, as well as to public health as a zoonosis. Its etiological agent, Mycobacterium bovis, belongs to the Mycobacterium tuberculosis complex (MTBC), a group of genetically monomorphic organisms featured by a remarkably high overall nucleotide identity (99.9%). Indeed, this characteristic is of major concern for correct typing and determination of strain-specific traits based on sequence diversity. Due to its historical economic dependence on cattle production, Uruguay is deeply affected by the prevailing incidence of Mycobacterium bovis. With the world's highest number of cattle per human, and its intensive cattle production, Uruguay represents a particularly suited setting to evaluate genomic variability among isolates, and the diversity traits associated to this pathogen. We compared 186 genomes from MTBC strains isolated worldwide, and found a highly structured population in M. bovis. The analysis of 23 new M. bovis genomes, belonging to strains isolated in Uruguay evidenced three groups present in the country. Despite presenting an expected highly conserved genomic structure and sequence, these strains segregate into a clustered manner within the worldwide phylogeny. Analysis of the non-pe/ppe differential areas against a reference genome defined four main sources of variability, namely: regions of difference (RD), variable genes, duplications and novel genes. RDs and variant analysis segregated the strains into clusters that are concordant with their spoligotype identities. Due to its high homoplasy rate, spoligotyping failed to reflect the true genomic diversity among worldwide representative strains, however, it remains a good indicator for closely related populations. This study introduces a comprehensive population structure analysis of worldwide M. bovis isolates. The incorporation and analysis of 23 novel Uruguayan M. bovis genomes, sheds light onto the genomic diversity of this

  11. Prevalence and Antimicrobial Susceptibility Profiles of Pathogen Isolated from Bovine Mastitis Milk in Transylvania, Romania

    Directory of Open Access Journals (Sweden)

    Cosmina Bouari

    2016-11-01

    Full Text Available Mastitis in cows, one of the most common and economically important infectious diseases of dairy cattle, all over the world, with significant impact due to economic losses, occurs when the udder becomes inflamed because the leukocytes are released into the mammary gland usually in response to bacteria invasion of the teat canal. The main objective of this study was to evaluate the in vitro antimicrobial susceptibility of bacteria isolated from milk in order to design specific control programs for bovine mastitis in this area. A total of 204 milk samples aseptically collected both from farms and private owners were processed during May 2014 and March 2016 within the Microbiology Laboratory of the Faculty of Veterinary Cluj-Napoca, Romania. The microbiological examination was carried out by inoculation on blood agar and MacConkey medium. After the overnight incubation in aerobic conditions, the identification of the isolates was performed using microscopic, cultural and biochemical methods. Biochemical identification was based on API 20 Biomerieux system. Susceptibility to antibiotics was evaluated using Kirby Bauer disk diffusion method on Mueller-Hinton agar; the antibiotics were represented by Amoxicillin and Clavulanic Acid, Ceftiofur, Florfenicol, Mastidiscs, Enrofloxacin, Penicillin and Tetracycline. Staphylococcus spp. was the most common isolated pathogen, in 54.9% of the specimens, followed by Streptococcus spp. in 20.1%, Escherichia coli in 10.78%, Klebsiella spp. in 8.34%, Bacillus spp. in 5.88%. The most frequent associations were represented by staphylococci-streptococci in 62.7% of the samples, followed by streptococci-bacillus in 19.8% of the samples. The most important etiological agents identified were Staphylococcus aureus, S uberis, Streptococcus agalactiae, and Escherichia coli. Antimicrobial susceptibility test for the total isolates revealed good sensitivity to Enrofloxacin, Mastidiscs and Amoxicillin and Clavulanic Acid

  12. Isolation and identification of local bacteria endophyte and screening of its antimicrobial property against pathogenic bacteria and fungi

    Science.gov (United States)

    Fikri, Ahmad Syairazie Ibrahim; Rahman, Irman Abdul; Nor, Norefrina Shafinaz Md; Hamzah, Ainon

    2018-04-01

    Endophytes are organisms, often fungi and bacteria that live in living plant cells. These organisms reside in the living tissues of the host plant in a variety of relationships, ranging from symbiotic to slightly pathogenic. The endophytes may produce a plethora of substances that have potential to be used in modern medicine, agriculture and industry. The aims of this study are to isolate, identify and screening antimicrobial activity of bacterial endophytes. The endophytes were isolated using nutrient agar, incubated at 37°C for 48 hours. Identification of the isolates were done based on morphological characteristics, biochemical tests and 16S rDNA molecular analysis. Disk diffusion method was used to screen for antimicrobial activity of metabolites from endophytes against pathogenic bacteria. Screening for antifungal activity of selected endophytes was done using dual culture method againts pathogenic fungi followed by Kirby-Bauer method. Results showed endophytes designated as B2c and B7b have positive antimicrobial activity. The metabolites from isolate B2c showed antimicrobial activity against pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Staphylococcus epidermis, while isolate B7b have positive activities againts MRSA, S. aureus and Pseudomonas aeruginosa. Isolates B2c displayed antifungal activity against Fusarium oxysporum, Fusarium solani, Phytophthora palmivora and Colletotrichum gloeosporioides. Identification using biochemical tests and 16S rDNA sequences identified isolate B2c as Pseudomonas resinovorans with 97% homology and isolate B7b as Bacillus subtilis with 98% homology.

  13. Microbial composition of guava (Psidium guajava), hibiscus ...

    African Journals Online (AJOL)

    Microbial composition of guava (Psidium guajava), hibiscus (Hibiscus-rosa sinensis), mango (Mangifera indica) and pumpkin (Telfairia occidentalis Hook) ... African Journal of Biotechnology ... The microbial genera isolated from this study showed that, both human and plant pathogens can colonize plants' phyllosphere.

  14. The pathogenicity of avian metapneumovirus subtype C wild bird isolates in domestic turkeys

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    Cha Ra Mi

    2013-01-01

    Full Text Available Abstract Background Avian metapneumovirus subtype C (aMPV/C causes severe upper respiratory disease in turkeys. Previous report revealed the presence of aMPV/C in wild birds in the southeast regions of the U.S. Methods In this study, aMPV/C positive oral swabs from American coots (AC and Canada geese (CG were passaged three times in the respiratory tract of specific pathogen free (SPF turkeys and used as aMPV/C P3 virus isolates in subsequent studies. Results Wild bird P3 isolates showed similar growth characteristics when compared to virulent aMPV/C in chicken embryo fibroblast ( CEF cell cultures and their glycoprotein G gene sequence was closely related to the G gene of aMPV/C Colorado reference virus. Three-day-old commercial or SPF turkeys were inoculated oculonasally with wild bird aMPV/C P3 isolates. At 5 and 7 days post-inoculation (DPI, severe clinical signs were observed in both of the AC and CG virus-exposed groups. Viral RNA was detected in tracheal swabs by reverse transcriptase polymerase chain reaction (RT-PCR. In addition, immunohistochemistry showed virus replication in the nasal turbinate and trachea. All virus-exposed turkeys developed positive antibody response by 14 DPI. Conclusions Our data demonstrate that aMPV/C wild bird isolates induced typical aMPV/C disease in the domestic turkeys.

  15. Incidence of bovine clinical mastitis in Jammu region and antibiogram of isolated pathogens

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    Adil Majid Bhat

    2017-08-01

    Full Text Available Aim: This study was conducted to evaluate the incidence of clinical mastitis in bovines of Jammu region, to identify the infectious organisms responsible for it, and the antimicrobial sensitivity of isolated pathogens. Materials and Methods: The study was conducted on cases that were presented to the Medicine Division of Teaching Veterinary Clinical Complex, Faculty of Veterinary Sciences and Animal Husbandry, R.S. Pura, Jammu, Jammu and Kashmir. A total of 260 cases of bovines were presented from June 30, 2012, to July 01, 2013, out of which 30 cases were of clinical mastitis. The diagnosis of clinical mastitis was made on the basis of history and clinical examination of affected animals. Results: Animal and quarter-wise incidence of clinical mastitis were found to be 11.5% and 5.76%, respectively. Of the 23 isolates obtained, Staphylococcus aureus (60.87% was the most frequently isolated organism, followed by coagulase negative Staphylococci (13.04%, Streptococcus uberis (4.35%, Streptococcus dysgalactiae (8.69%, and Escherichia coli (13.04%. The antimicrobial sensitivity of isolates revealed maximum sensitivity to enrofloxacin, gentamicin, amoxicillin/ sulbactam, ceftriaxone/tazobactam, ceftizoxime, ampicillin/sulbactam and least sensitivity for oxytetracycline and penicillin. Conclusion: Staphylococcus spp. is the major causative agent of clinical mastitis in bovines of Jammu region. The causative agents of the clinical mastitis were most sensitive to enrofloxacin and gentamicin.

  16. Isolation and pathogenicity of Xylella fastidiosa from grapevine and almond in Iran

    Directory of Open Access Journals (Sweden)

    Naser AMANIFAR

    2014-09-01

    Full Text Available Symptoms similar to those of Pierce’s disease (PD of grapevine and leaf scorch of almond were observed in vineyards and almond orchards in several provinces of Iran. Grafting of scions from symptomatic almond trees onto seedlings of a local almond (cv. Mamaee under greenhouse conditions resulted in the transmission of the leaf scorch agent. A number of symptomatic samples from orchard and greenhouse plants were positive for presence of Xylella fastidiosa when tested by DAS-ELISA and PCR with X. fastidiosa specific antibodies and primers. A Gram-negative bacterium similar to X. fastidiosa was isolated on ‘periwinkle wilt’ (PW medium. Selected isolates induced symptoms similar to those caused by X. fastidiosa when inoculated on Nicotiana tabacum, seedlings of almond and grapevine under greenhouse conditions. DAS-ELISA and PCR confirmed the identity of the isolated bacteria. On the basis of disease symptoms, graft transmission, isolation on specific X. fastidiosa culture medium, pathogenicity tests and positive reactions in DAS-ELISA and PCR, X. fastidiosa is associated with almond leaf scorch and Pierce’s disease in grapevine in Iran. This is the first report on the presence of X. fastidiosa in the Middle East and western Asia.

  17. The pathogenicity of avian metapneumovirus subtype C wild bird isolates in domestic turkeys.

    Science.gov (United States)

    Cha, Ra Mi; Yu, Qingzhong; Zsak, Laszlo

    2013-01-30

    Avian metapneumovirus subtype C (aMPV/C) causes severe upper respiratory disease in turkeys. Previous report revealed the presence of aMPV/C in wild birds in the southeast regions of the U.S. In this study, aMPV/C positive oral swabs from American coots (AC) and Canada geese (CG) were passaged three times in the respiratory tract of specific pathogen free (SPF) turkeys and used as aMPV/C P3 virus isolates in subsequent studies. Wild bird P3 isolates showed similar growth characteristics when compared to virulent aMPV/C in chicken embryo fibroblast ( CEF) cell cultures and their glycoprotein G gene sequence was closely related to the G gene of aMPV/C Colorado reference virus. Three-day-old commercial or SPF turkeys were inoculated oculonasally with wild bird aMPV/C P3 isolates. At 5 and 7 days post-inoculation (DPI), severe clinical signs were observed in both of the AC and CG virus-exposed groups. Viral RNA was detected in tracheal swabs by reverse transcriptase polymerase chain reaction (RT-PCR). In addition, immunohistochemistry showed virus replication in the nasal turbinate and trachea. All virus-exposed turkeys developed positive antibody response by 14 DPI. Our data demonstrate that aMPV/C wild bird isolates induced typical aMPV/C disease in the domestic turkeys.

  18. Flow-through immunomagnetic separation system for waterborne pathogen isolation and detection: Application to Giardia and Cryptosporidium cell isolation

    Energy Technology Data Exchange (ETDEWEB)

    Ramadan, Qasem, E-mail: qasem.alramadan@epfl.ch [Bioelectronics Program, Institute of Microelectronics, 11 Science Park Road, Singapore 117685 (Singapore); Christophe, Lay; Teo, William; ShuJun, Li; Hua, Feng Han [Bioelectronics Program, Institute of Microelectronics, 11 Science Park Road, Singapore 117685 (Singapore)

    2010-07-12

    Simultaneous sample washing and concentration of two waterborne pathogen samples were demonstrated using a rotational magnetic system under continuous flow conditions. The rotation of periodically arranged small permanent magnets close to a fluidic channel carrying magnetic particle suspension allows the trapping and release of particles along the fluidic channel in a periodic manner. Each trapping and release event resembles one washing cycle. The performance of the magnetic separation system (MSS) was evaluated in order to test its functionality to isolate magnetic-labelled protozoan cells from filtered, concentrated tap water, secondary effluent water, and purified water. Experimental protocols described in US Environmental Protection Agency method 1623 which rely on the use of a magnetic particle concentrator, were applied to test and compare our continuous flow cell separation system to the standard magnetic bead-based isolation instruments. The recovery efficiencies for Giardia cysts using the magnetic tube holder and our magnetic separation system were 90.5% and 90.1%, respectively, from a tap water matrix and about 31% and 18.5%, respectively, from a spiked secondary effluent matrix. The recovery efficiencies for Cryptosporidium cells using the magnetic tube holder and our magnetic separation system were 90% and 83.3%, respectively, from a tap water matrix and about 38% and 36%, respectively, from a spiked secondary effluent matrix. Recoveries from all matrices with the continuous flow system were typically higher in glass tubing conduits than in molded plastic conduits.

  19. Distribution of pathogenic microorganisms isolated from dental hospital workers in Korea

    Directory of Open Access Journals (Sweden)

    Su Jung Kim

    2013-04-01

    Full Text Available With the significant rise in hospital infection management in dental hospitals as well as in hospitals, and in order to identify the distribution of pathogenic bacteria on hands and nasal cavity of workers in a dental hospital, bacteria from the hands and nasal cavities of six dentists and 44 dental hygienists from four dental hospitals were investigated. The results showed Staphylococcus aureus (13, Staphylococcus capitis (1, Staphylococcus epidermidis (12, Staphylococcus hominis (4, Staphylococcus warneri (3, Staphylococcus xylosus (14, Staphylococcus. Lugdunensis (1, and Neisseria spp. (2 were isolated from the nasal cavity and Staphylococcus aureus (9, Staphylococcus capitis (4, Staphylococcus epidermidis (16, Staphylococcus hominis (8, Staphylococcus warneri (5, Staphylococcus xylosus (22, Staphylococcus leutus (3, Micrococcus spp. (4, Staphylococcus cohnii (1, Serratia marcescens (2, Pseudomonas aeruginosa (3, Klebsiella pneumonia (2 and Pseudomonas pneumotropica (1 from the hands. An antimicrobial disk diffusion test was conducted on Staphylococcus aureus isolated from the hands and nasal cavity to detect MRSA by means of oxacillin. Two strains were detected. When the genes of penicillin binding protein 2 (mecA were detected from the 2 strains, MRSA was found from both strains. The results of this investigation on the distribution of various pathogenic bacteria and MRSA on hands and nasal cavity of workers of a dental hospital, will contribute to the basic data for the future infection management in a dental hospital.

  20. Evaluation of methyl bromide alternatives efficacy against soil-borne pathogens, nematodes and soil microbial community.

    Directory of Open Access Journals (Sweden)

    Hongwei Xie

    Full Text Available Methyl bromide (MB and other alternatives were evaluated for suppression of Fusarium spp., Phytophthora spp., and Meloidogyne spp. and their influence on soil microbial communities. Both Fusarium spp. and Phytophthora spp. were significantly reduced by the MB (30.74 mg kg-1, methyl iodide (MI: 45.58 mg kg-1, metham sodium (MS: 53.92 mg kg-1 treatments. MS exhibited comparable effectiveness to MB in controlling Meloidogyne spp. and total nematodes, followed by MI at the tested rate. By contrast, sulfuryl fluoride (SF: 33.04 mg kg-1 and chloroform (CF: 23.68 mg kg-1 showed low efficacy in controlling Fusarium spp., Phytophthora spp., and Meloidogyne spp. MB, MI and MS significantly lowered the abundance of different microbial populations and microbial biomass in soil, whereas SF and CF had limited influence on them compared with the control. Diversity indices in Biolog studies decreased in response to fumigation, but no significant difference was found among treatments in PLFA studies. Principal component and cluster analyses of Biolog and PLFA data sets revealed that MB and MI treatments greatly influenced the soil microbial community functional and structural diversity compared with SF treatment. These results suggest that fumigants with high effectiveness in suppressing soil-borne disease could significantly influence soil microbial community.

  1. Acinetobacter baumannii Isolated from Lebanese Patients: Phenotypes and Genotypes of Resistance, Clonality, and Determinants of Pathogenicity.

    Science.gov (United States)

    Dahdouh, Elias; Hajjar, Micheline; Suarez, Monica; Daoud, Ziad

    2016-01-01

    Introduction: Acinetobacter baumannii is a nosocomial pathogen that usually affects critically ill patients. High mortality rates have been associated with MDR A. baumannii infections. Carbapenem resistance among these isolates is increasing worldwide and is associated with certain International Clones (ICs) and oxacillinases (OXAs). Moreover, this organism possesses a wide range of virulence factors, whose expression is not yet fully understood. In this study, clinical A. baumannii isolates are characterized in terms of antibiotic resistance, mechanisms of carbapenem resistance, clonality, and virulence. Materials and Methods: A. baumannii clinical isolates ( n = 90) where obtained from a tertiary care center in Beirut, Lebanon. API 20NE strips in addition to the amplification of bla OXA-51-like were used for identification. Antibiotic susceptibility testing by disk diffusion was then performed in addition to PCRs for the detection of the most commonly disseminated carbapenemases. Clonality was determined by tri-locus PCR typing and doubling times were determined for isolates with varying susceptibility profiles. Biofilm formation, hemolysis, siderophore production, proteolytic activity, and surface motility was then determined for all the isolates. Statistical analysis was then performed for the determination of associations. Results and Discussion: 81 (90%) of the isolates were resistant to carbapenems. These high rates are similar to other multi-center studies in the country suggesting the need of intervention on a national level. 74 (91.3%) of the carbapenem resistant isolates harbored bla OXA-23-like including two that also harbored bla OXA-24-like . 88.9% of the A. baumannii isolates pertained to ICII and three other international clones were detected, showing the wide dissemination of clones into geographically distinct locations. Virulence profiles were highly diverse and no specific pattern was observed. Nevertheless, an association between motility

  2. Survival after pathogen exposure in group-living insects: don't forget the stress of social isolation!

    Science.gov (United States)

    Kohlmeier, P; Holländer, K; Meunier, J

    2016-09-01

    A major cost of group-living is its inherent risk of pathogen infection. To limit this risk, many group-living animals have developed the capability to prophylactically boost their immune system in the presence of group members and/or to mount collective defences against pathogens. These two phenomena, called density-dependent prophylaxis and social immunity, respectively, are often used to explain why, in group-living species, individuals survive better in groups than in isolation. However, this survival difference may also reflect an alternative and often overlooked process: a cost of social isolation on individuals' capability to fight against infections. Here, we disentangled the effects of density-dependent prophylaxis, social immunity and stress of social isolation on the survival after pathogen exposure in group-living adults of the European earwig Forficula auricularia. By manipulating the presence of group members both before and after pathogen exposure, we demonstrated that the cost of being isolated after infection, but not the benefits of social immunity or density-dependent prophylaxis, explained the survival of females. Specifically, females kept constantly in groups or constantly isolated had higher survival rates than females that were first in groups and then isolated after infection. Our results also showed that this cost of social isolation was absent in males and that social isolation did not reduce the survival of noninfected individuals. Overall, this study gives a new perspective on the role of pathogens in social evolution, as it suggests that an apparently nonadaptive, personal immune process may promote the maintenance of group-living under pathogenic environments. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  3. Microbial Quality, Safety, and Pathogen Detection by Using Quantitative PCR of Raw Salad Vegetables Sold in Dhanbad City, India.

    Science.gov (United States)

    Mritunjay, Sujeet K; Kumar, Vipin

    2017-01-01

    Consumption of ready-to-eat fresh vegetables has increased worldwide, with a consequent increase in outbreaks caused by foodborne pathogens. In the Indian subcontinent, raw fresh vegetables are usually consumed without washing or other decontamination procedures, thereby leading to new food safety threats. In this study, the microbiological quality and pathogenic profile of raw salad vegetables was evaluated through standard protocols. In total, 480 samples (60 each of eight different salad vegetables) of cucumber, tomato, carrot, coriander, cabbage, beetroot, radish, and spinach were collected from different locations in Dhanbad, a city famous for its coal fields and often called the "Coal Capital of India." The samples were analyzed for total plate count, total coliforms, Escherichia coli , E. coli O157:H7, Listeria monocytogenes , and Salmonella spp. Incidences of pathogens were detected through quantitative PCR subsequent to isolation. Results showed that 46.7% (for total plate counts) and 30% (for total coliforms) of samples were unacceptable for consumption per the Food Safety and Standards Authority of India. Pathogenic microorganisms were detected in 3.7% of total samples. E. coli O157:H7 was detected in three samples of spinach (2) and beetroot ( 1 ); L. monocytogenes was detected in 14 samples of spinach ( 8 ), tomato ( 3 ), cucumber ( 2 ), and radish ( 1 ); and Salmonella spp. were detected in 16 samples of spinach ( 7 ), tomato ( 3 ), beetroot ( 2 ), cucumber ( 2 ), carrot ( 1 ), and radish ( 1 ). Pathogens were not detected in any of the cabbage and coriander samples.

  4. Anti-Microbial Resistance Profiles Of E. Coli Isolated From Free Range Chickens In Urban And Rural Environments Of Imo State, Nigeria

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    Okoli IC

    2006-07-01

    Full Text Available Information on the resistance profiles of normal intestinal flora of extensively reared chickens that hardly receive antibiotics in the developing countries can serve as important means of understanding the human/animal pathogens drug resistance interactions in the zone. Three hundred and fifty E. coli isolates, comprising 133 from urban and 217 from rural sites in Imo state, Nigeria, were screened for anti-microbial resistance profile against 10 antibiotics using the disc diffusion method. Overall percentage anti-microbial resistance of the isolates against cotrimoxazole, ampicillin, nalidixic acid, chloramphenicol and nitrofurantoin (72–92% were very high. The organisms were highly sensitive to other antibiotics, especially gentamicin and ciprofloxacin. The 59.5% overall mean percentage resistance recorded at the urban area was significantly higher than the 46.8% recorded at the rural area (p<0.05. With the exception of the figures for cotrimoxazole and ampicillin, resistance values obtained against the other antibiotics at the urban sites were statistically higher than those obtained at the rural sites (p<0.05. Zero resistance was recorded against the fluoroquinolones, norfloxacin and ciprofloxacin at all the rural sites except at Enyiogwugwu where a 28.6% resistance was obtained against norfloxacin. Since free-range chickens rarely receive antibiotic medication, it is concluded that the highly resistant E. coli organisms isolated from them may be reflecting consequences of human drug use in the study areas.

  5. Shrimp pathogenicity, hemolysis, and the presence of hemolysin and TTSS genes in Vibrio harveyi isolated from Thailand.

    Science.gov (United States)

    Rattanama, Pimonsri; Srinitiwarawong, Kanchana; Thompson, Janelle R; Pomwised, Rattanaruji; Supamattaya, Kidchakarn; Vuddhakul, Varaporn

    2009-09-23

    The virulence factors of Vibrio harveyi, the causative agent of luminous vibriosis, are not completely understood. We investigated the correlations between shrimp mortality, hemolysis, the presence of a hemolysin gene (vhh), and a gene involved in the type III secretion system (the Vibrio calcium response gene vcrD). V harveyi HY01 was isolated from a shrimp that died from vibriosis, and 36 other V. harveyi isolates were obtained from fish and shellfish in Hat Yai city, Thailand. An ocean isolate of V. harveyi BAA-1116 was also included. Thirteen isolates including V harveyi HYO1 caused shrimp death 12 h after injection. Most V harveyi isolates in this group (designated as Group A) caused hemolysis on prawn blood agar. None of the shrimp died after injection with V harveyi BAA-1116. Molecular analysis of all V harveyi isolates revealed the presence of vcrD in both pathogenic and non-pathogenic strains. Although vhh was detected in all V harveyi isolates, some isolates did not cause hemolysis, indicating that vhh gene expression might be regulated. Analysis of the V harveyi HYO1 genome revealed a V cholerae like-hemolysin gene, hlyA (designated as hhl). Specific primers designed for hhl detected this gene in 3 additional V harveyi isolates but the presence of this gene was not correlated with pathogenicity. Random amplified polymorphic DNA (RAPD) analysis revealed a high degree of genetic diversity in all V harveyi isolates, and there were no correlations among the hhl-positive isolates or the pathogenic strains.

  6. In Vitro Activities of Terbinafine against Cutaneous Isolates of Candida albicans and Other Pathogenic Yeasts

    Science.gov (United States)

    Ryder, Neil S.; Wagner, Sonja; Leitner, Ingrid

    1998-01-01

    Terbinafine is active in vitro against a wide range of pathogenic fungi, including dermatophytes, molds, dimorphic fungi, and some yeasts, but earlier studies indicated that the drug had little activity against Candida albicans. In contrast, clinical studies have shown topical and oral terbinafine to be active in cutaneous candidiasis and Candida nail infections. In order to define the anti-Candida activity of terbinafine, we tested the drug against 350 fresh clinical isolates and additional strains by using a broth dilution assay standardized according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS) M27-A assay. Terbinafine was found to have an MIC of 1 μg/ml for reference C. albicans strains. For 259 clinical isolates, the MIC at which 50% of the isolates are inhibited (MIC50) of terbinafine was 1 μg/ml (fluconazole, 0.5 μg/ml), and the MIC90 was 4 μg/ml (fluconazole, 1 μg/ml). Terbinafine was highly active against Candida parapsilosis (MIC90, 0.125 μg/ml) and showed potentially interesting activity against isolates of Candida dubliniensis, Candida guilliermondii, Candida humicola, and Candida lusitaniae. It was not active against the Candida glabrata, Candida krusei, and Candida tropicalis isolates in this assay. Cryptococcus laurentii and Cryptococcus neoformans were highly susceptible to terbinafine, with MICs of 0.06 to 0.25 μg/ml. The NCCLS macrodilution assay provides reproducible in vitro data for terbinafine against Candida and other yeasts. The MICs for C. albicans and C. parapsilosis are compatible with the known clinical efficacy of terbinafine in cutaneous infections, while the clinical relevance of its activities against the other species has yet to be determined. PMID:9593126

  7. Microbial Flora Isolated from Polluted and Non-Polluted Coastal Waters of Karachi

    International Nuclear Information System (INIS)

    Shaheen, A.; Baig, H. S.; Kazmi, S. U.

    2016-01-01

    Marine pollution has now become worldwide environmental concern. Continuous discharge of untreated industrial effluent, municipal and power plant contaminated wastewater has been a serious threat to marine habitat, aesthetic values and interest of visitors to coastal areas. Karachi is the largest city of Pakistan and industrial hub of the Arabian Sea. In this investigation, samples of sediment, water, flora and fauna were taken from nine selected stations on Karachi coast included three stations represented major creeks i.e. Korangi, Gizri and Chinna Creek. These samples were taken during north-east and south-west monsoonal period in 2014. Bacterial flora isolated and identified from samples collected from these sites by conventional method. Among isolated and identified bacteria e.g. Vibrio alginolyticus, Escherichia coli and Streptococuss anginosus were the most dominant species contributing 21.43, 19.64 and 15.18 percent of total assemblage respectively. Among selected sample stations, Korangi creek station was found to be most polluted with coliform and other pathogenic bacteria. These results clearly indicate that threats from these pathogens are not only to marine life but also to the large number of visitors coming to beaches and residents of surrounding area. Moreover; immediate action should be taken to restrict the growth of these pathogens by taking measures to treat the municipal and industrial effluent to avoid outbreak of any disease in future. (author)

  8. Antimicrobial susceptibility survey of pathogens isolated from selected patients in Northern Italy

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    Elisabetta Maioli

    2005-03-01

    Full Text Available The Clinical Microbiology Laboratory of the University of Genoa participated, during the year 2003, in an international antimicrobial surveillance program.The collection of isolates was done according to the site of infection and/or type of patient. Four hundred twenty (420 clinical isolates were analyzed during this year and the frequencies of the different pathogens were investigated. A reference centre carried out susceptibility tests. Oxacillin-resistant Staphylococcus aureus represented 47.6% of all S. aureus isolates from blood stream infections and 33.3% of all S. aureus isolated from skin and soft tissue infections in hospitalised patients.These strains showed resistance to most of the antimicrobial agents evaluated, except vancomycin, teicoplanin, quinupristin/dalfopristin and linezolid which registered 100% of susceptibility. Some isolates from blood stream infections such as E. coli demonstrated resistance to ciprofloxacin (23.3%, levofloxacin (20%, and gatifloxacin (16.6%, and Klebsiella pneumoniae was resistant (18% to all fluoroquinolones tested. Pseudomonas aeruginosa manifested resistance to ciprofloxacin (16.6%, while 27.7% of these strains were resistant both to levofloxacin and gatifloxacin. All the Enterobacter cloacae isolated from blood were susceptible to ciprofloxacin, levofloxacin and gatifloxacin. Haemophilus influenzae and Moraxella catarrhalis collected from community-acquired respiratory tract infections were all inhibited by ciprofloxacin, levofloxacin and gatifloxacin. E. coli isolated from urinary tract infections in hospitalised patients were resistant to ciprofloxacin, levofloxacin and gatifloxacin (2.7%. All Salmonella spp. collected from samples of patients affected by infections of the gastro-intestinal tract were susceptible to all fluoroquinolones. Penicillin resistance in Streptococcus pneumoniae was found in 21.4% of isolates from patients with respiratory tract infections. Fluoroquinolone resistance was

  9. Pathogenic strains of Yersinia enterocolitica isolated from domestic dogs (Canis familiaris) belonging to farmers are of the same subtype as pathogenic Y. enterocolitica strains isolated from humans and may be a source of human infection in Jiangsu Province, China.

    Science.gov (United States)

    Wang, Xin; Cui, Zhigang; Wang, Hua; Tang, Liuying; Yang, Jinchuan; Gu, Ling; Jin, Dong; Luo, Longze; Qiu, Haiyan; Xiao, Yuchun; Xiong, Haiping; Kan, Biao; Xu, Jianguo; Jing, Huaiqi

    2010-05-01

    We isolated 326 Yersinia enterocolitica strains from 5,919 specimens from patients with diarrhea at outpatient clinics, livestock, poultry, wild animals, insect vectors, food, and the environment in the cities of Nantong and Xuzhou in Jiangsu Province, China, from 2004 to 2008. The results showed that the 12 pathogenic strains were of the O:3 serotype. Six strains were isolated from domestic dogs (Canis familiaris) belonging to farmers and were found to be the primary carriers of pathogenic Y. enterocolitica strains, especially in Xuzhou. Pulsed-field gel electrophoresis analysis of the pathogenic strains from dogs belonging to farmers showed that they shared the same patterns as strains from diarrhea patients isolated in 1994. This indicates that the strains from domestic dogs have a close correlation with the strains causing human infections.

  10. Evaluation of the egg transmission and pathogenicity of Mycoplasma gallisepticum isolates genotyped as ts-11.

    Science.gov (United States)

    Armour, Natalie K; Ferguson-Noel, Naola

    2015-01-01

    Live Mycoplasma gallisepticum vaccines are used for the control of respiratory disease, egg production losses and egg transmission associated with M. gallisepticum infection in long-lived poultry. The first field case of apparent increased virulence and vertical transmission of ts-11, a live M. gallisepticum vaccine, has been reported. In that study a M. gallisepticum isolate from the broiler progeny of ts-11-vaccinated breeders was genotyped as ts-11 by sequence analysis of four different genetic targets and Random Amplified Polymorphic DNA and found to be significantly more virulent than ts-11 vaccine. The objective of the current study was to evaluate the rate of egg transmission and pathogenicity of ts-11 vaccine and isolates recovered from ts-11-vaccinated breeders (K6222B) and their broiler progeny (K6216D) which had been genotyped as ts-11. Groups of 28-week-old specific pathogen-free chickens at 87% average weekly egg production were inoculated with sterile broth media (negative controls), ts-11 vaccine, K6222B, K6216D or R strain (positive controls) by eye-drop and aerosol. K6216D transmitted via the egg at an average rate of 4.0% in the third and fourth weeks post-infection, while egg transmission of K6222B and ts-11 vaccine was not detected. M. gallisepticum was isolated from the air sacs, ovaries and oviducts of hens infected with K6216D and K6222B, but not from those infected with ts-11 vaccine. K6216D and K6222B both induced respiratory signs and significantly more tracheal colonization and more severe tracheal and air sac lesions than ts-11 vaccine (P ≤ 0.05). There were no substantial differences in the egg production of ts-11, K6216D and K6222B infected groups. These results provide the first conclusive evidence of transovarian transmission of an isolate genotyped as ts-11 and indicate that isolates genotyed as ts-11 vary in their virulence and ability to transmit via the egg.

  11. Characterization of low pathogenicity avian influenza viruses isolated from wild birds in Mongolia 2005 through 2007

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    Sodnomdarjaa Ruuragchaa

    2009-11-01

    Full Text Available Abstract Background Since the emergence of H5N1 high pathogenicity (HP avian influenza virus (AIV in Asia, numerous efforts worldwide have focused on elucidating the relative roles of wild birds and domestic poultry movement in virus dissemination. In accordance with this a surveillance program for AIV in wild birds was conducted in Mongolia from 2005-2007. An important feature of Mongolia is that there is little domestic poultry production in the country, therefore AIV detection in wild birds would not likely be from spill-over from domestic poultry. Results During 2005-2007 2,139 specimens representing 4,077 individual birds of 45 species were tested for AIV by real time RT-PCR (rRT-PCR and/or virus isolation. Bird age and health status were recorded. Ninety rRT-PCR AIV positive samples representing 89 individual birds of 19 species including 9 low pathogenicity (LP AIVs were isolated from 6 species. A Bar-headed goose (Anser indicus, a Whooper swan (Cygnus cygnus and 2 Ruddy shelducks (Tadorna ferruginea were positive for H12N3 LP AIV. H16N3 and H13N6 viruses were isolated from Black-headed gulls (Larus ridibundus. A Red-crested pochard (Rhodonessa rufina and 2 Mongolian gulls (Larus vagae mongolicus were positive for H3N6 and H16N6 LP AIV, respectively. Full genomes of each virus isolate were sequenced and analyzed phylogenetically and were most closely related to recent European and Asian wild bird lineage AIVs and individual genes loosely grouped by year. Reassortment occurred within and among different years and subtypes. Conclusion Detection and/or isolation of AIV infection in numerous wild bird species, including 2 which have not been previously described as hosts, reinforces the wide host range of AIV within avian species. Reassortment complexity within the genomes indicate the introduction of new AIV strains into wild bird populations annually, however there is enough over-lap of infection for reassortment to occur. Further work is

  12. Effect of UV-C irradiation on growth, sporulation and pathogenicity of cochliobolus sativus isolates

    International Nuclear Information System (INIS)

    Jawhar, M.; Arabi, M.I.E.

    1999-12-01

    More than 30 isolates of Cochliobolus sativus, the causal agent of common root rot disease; were collected from different regions of Syria. Seven of them were exposed to UV-C light for 40 or 60 h . at a dose rate of 2.52x10 -3 W/cm 2 . A significant increases in the mycelium growth and sporulation were detected (p<0.001). Within the studied range of UV wave length, these two parameters were increased upon increasing the period of exposure to UV-C light. The pathogenicity of four isolates was evaluated after 60 h. of UV irradiation. The response to UV irradiation varied among these isolates, and resulted in an increase in their virulence level (as assessed by evaluating disease severity on sub-crown internodes). Five barley genotypes possessing different levels of resistance to C. sativus were studied. Arabi Abiad was the most susceptible cultivar whereas, Taka 76 line was moderately susceptible. It is concluded that it is possible to implement the positive effect of low doses of UV-C in stimulating the sporulation of fungi, which are difficult to sporulate on artificial media. (author)

  13. Antimicrobial activity of Algerian honey on subclinical mastitis pathogens isolated from goat's milk

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    A. Bourabah

    2014-04-01

    Full Text Available Aim: The aim of the present study was to determine the susceptibility of subclinical mastitis pathogens isolated from goat's milk and to evaluate the antimicrobial activity of Algerian honey on mastitis causing bacteria. Materials and Methods: The antibacterial activity against the isolated bacteria was evaluated by determining the Minimal Inhibitory Concentration (MIC, using the agar incorporation method. Results: The results showed that both Micrococcus spp. and Klebsiella spp. were susceptible to Streptomycin and tetracycline, while Pseudomonas aeruginosa, E coli, Enterobacter spp., Bacillus spp., and Coagulase Negative Staphyloccoci (CNS were preferentially susceptible to Streptomycin. However, Streptococcus D was the most resistant to the tested antibiotics whereas Staphylococcus aureus was the most susceptible to all the studied antibiotics. As regards to the antimicrobial activity of honey, the measured values were comprised between 11 and 14%. Conclusion: The results reveal that antimicrobial drugs susceptibility tests in goat subclinical mastitis might be necessary before the treatment. Algerian honey exhibited in vitro antimicrobial activity against different isolated bacteria in goat mastitis.

  14. Isolation and regeneration protoplast of an oil palm pathogen, Ganoderma boninense

    Science.gov (United States)

    Irene, Liza Isaac; Bakar, Farah Diba Abu; Idris, Abu Seman; Murad, Abdul Munir Abdul

    2015-09-01

    Ganoderma boninense is a known cause for basal stem rot (BSR) in oil palm. Thus, to curb the infection towards oil palm, the establishment of protoplast isolation and regeneration protocol is crucial to be studied. This will provide information on the functional genes especially those which leads towards infection and pathogenicity. In this study, a method was outlined to isolated protoplast in G. boninense by manipulating parameters such as mycelium age, concentration of lysing enzyme, and duration of mycelia incubation in lytic solution. The results shows that from 0.1 g of wet weight mycelia, the highest protoplast yield obtained was 5.5 × 108 protoplast/ml using 5th day old culture in a lytic mixture containing 2.0 % of lysing enzyme incubated for 4 hours at 30 °C with agitation of 80-100 rpm. The highest percentage of protoplast regeneration obtained from this study was 0.2 % using CYM medium supplemented with 0.6 M sorbitol. To date, this is the first report of protoplast isolation and regeneration for this phytopathogen.

  15. Isolation of microbial native Stumps with cellulolytic activity of a compost process

    International Nuclear Information System (INIS)

    Jaramillo G, Marisol; Ruiz V Orlando Simon; Yepes P, Maria del Socorro; Montoya C, Olga Ines

    2003-01-01

    The isolation, selection adaptation and handling of native microorganisms coming from organic waste are an alternative to avoid the accumulation and the lack of the proper use of these undesirable materials. This organic waste is a source for obtaining microbial strains, which are potentially producers of Industrial enzymes and, at the same time, it works as substrate so that these organisms can transform it into compost or organic manure. In this work, 39 native strains of microorganisms with potential cellulolytic activity coming from the organic waste of the urban and rural sector, from the Compost Plant of Marinilla Antioquia) municipality, were isolated, evaluated and purified. The waste was previously selected and then submitted to an aerobic degradation or compost. The microbial strains were isolated in a selective medium with carboxymethyl cellulose (CMC), of the phases mesophile, termophile, cooling and maturation of the compost process. Eighty-two percent (82%)of the obtained colonies were identified, in principle as Bacillus, because of their morphology and their reaction to the Gram coloration. The fungi population was seen only during the cooling phase. Then, the potential cellulolytic activity was evaluated qualitatively in a solid medium with the Congo Red coloration, with which the Beta-endoglucanase activity was evaluated through the formation of clarified zones. Such staining was applied in two mediums with CMC with and without glucose It was observed that 33.3% of the isolated organisms produced the enzyme In both mediums; however, 25.6% of microorganisms did not show the production of this enzyme, and only 15.8% did not require the inducers to produce it

  16. Comparison of filters for concentrating microbial indicators and pathogens in lake-water samples

    Science.gov (United States)

    Francy, Donna S.; Stelzer, Erin A.; Brady, Amie M.G.; Huitger, Carrie; Bushon, Rebecca N.; Ip, Hon S.; Ware, Michael W.; Villegas, Eric N.; Gallardo, Vincent; Lindquist, H.D. Alan

    2013-01-01

    Bacterial indicators are used to indicate increased health risk from pathogens and to make beach closure and advisory decisions; however, beaches are seldom monitored for the pathogens themselves. Studies of sources and types of pathogens at beaches are needed to improve estimates of swimming-associated health risks. It would be advantageous and cost-effective, especially for studies conducted on a regional scale, to use a method that can simultaneously filter and concentrate all classes of pathogens from the large volumes of water needed to detect pathogens. In seven recovery experiments, stock cultures of viruses and protozoa were seeded into 10-liter lake water samples, and concentrations of naturally occurring bacterial indicators were used to determine recoveries. For the five filtration methods tested, the highest median recoveries were as follows: glass wool for adenovirus (4.7%); NanoCeram for enterovirus (14.5%) and MS2 coliphage (84%); continuous-flow centrifugation (CFC) plus Virocap (CFC+ViroCap) for Escherichia coli (68.3%) and Cryptosporidium (54%); automatic ultrafiltration (UF) for norovirus GII (2.4%); and dead-end UF for Enterococcus faecalis (80.5%), avian influenza virus (0.02%), and Giardia (57%). In evaluating filter performance in terms of both recovery and variability, the automatic UF resulted in the highest recovery while maintaining low variability for all nine microorganisms. The automatic UF was used to demonstrate that filtration can be scaled up to field deployment and the collection of 200-liter lake water samples.

  17. Genetic and Pathogenic Variability of Fusarium oxysporum f. sp. cepae Isolated from Onion and Welsh Onion in Japan.

    Science.gov (United States)

    Sasaki, Kazunori; Nakahara, Katsuya; Tanaka, Shuhei; Shigyo, Masayoshi; Ito, Shin-ichi

    2015-04-01

    Fusarium oxysporum f. sp. cepae causes Fusarium basal rot in onion (common onion) and Fusarium wilt in Welsh onion. Although these diseases have been detected in various areas in Japan, knowledge about the genetic and pathogenic variability of F. oxysporum f. sp. cepae is very limited. In this study, F. oxysporum f. sp. cepae was isolated from onion and Welsh onion grown in 12 locations in Japan, and a total of 55 F. oxysporum f. sp. cepae isolates (27 from onion and 28 from Welsh onion) were characterized based on their rDNA intergenic spacer (IGS) and translation elongation factor-1α (EF-1α) nucleotide sequences, vegetative compatibility groups (VCGs), and the presence of the SIX (secreted in xylem) homologs. Phylogenetic analysis of IGS sequences showed that these isolates were grouped into eight clades (A to H), and 20 onion isolates belonging to clade H were monophyletic and assigned to the same VCG. All the IGS-clade H isolates possessed homologs of SIX3, SIX5, and SIX7. The SIX3 homolog was located on a 4 Mb-sized chromosome in the IGS-clade H isolates. Pathogenicity tests using onion seedlings showed that all the isolates with high virulence were in the IGS-clade H. These results suggest that F. oxysporum f. sp. cepae isolates belonging to the IGS-clade H are genetically and pathogenically different from those belonging to the other IGS clades.

  18. Detection of catabolic genes in indigenous microbial consortia isolated from a diesel-contaminated soil

    International Nuclear Information System (INIS)

    Milcic-Terzic, J.; Saval, S.; Lopez-Vidal, Y.; Vrvic, M.M.

    2001-01-01

    Bioremediation is often used for in situ remediation of petroleum-contaminated sites. The primary focus of this study was on understanding the indigenous microbial community which can survive in contaminated environment and is responsible for the degradation. Diesel, toluene and naphthalene-degrading microbial consortia were isolated from diesel-contaminated soil by growing on selective hydrocarbon substrates. The presence and frequency of the catabolic genes responsible for aromatic hydrocarbon biodegradation (xylE, ndoB) within the isolated consortia were screened using polymerase chain reaction PCR and DNA-DNA colony hybridization. The diesel DNA-extract possessed both the xylE catabolic gene for toluene, and the nah catabolic gene for polynuclear aromatic hydrocarbon degradation. The toluene DNA-extract possessed only the xylE catabolic gene, while the naphthalene DNA-extract only the ndoB gene. Restriction enzyme analysis with HaeIII indicated similar restriction patterns for the xylE gene fragment between toluene DNA-extract and a type strain, Pseudomonas putida ATCC 23973. A substantial proportion (74%) of the colonies from the diesel-consortium possessed the xylE gene, and the ndoB gene (78%), while a minority (29%) of the toluene-consortium harbored the xylE gene. 59% of the colonies from the naphthalene-consortium had the ndoB gene, and did not have the xylE gene. These results indicate that the microbial population has been naturally enriched in organisms carrying genes for aromatic hydrocarbon degradation and that significant aromatic biodegradative potential exists at the site. Characterization of the population genotype constitutes a molecular diagnosis which permits the determination of the catabolic potential of the site to degrade the contaminant present. (author)

  19. Rapid identification of pathogenic streptococci isolated from moribund red tilapia (Oreochromis spp.).

    Science.gov (United States)

    Abdelsalam, Mohamed; Elgendy, Mamdouh Y; Shaalan, Mohamed; Moustafa, Mohamed; Fujino, Masayuki

    2017-03-01

    Accurate and rapid identification of bacterial pathogens of fish is essential for the effective treatment and speedy control of infections. Massive mortalities in market-sized red tilapia (Oreochromis spp.) were noticed in mariculture concrete ponds in northern Egypt. Histopathological examination revealed marked congestion in the central vein of the liver with the presence of bacterial aggregates inside the lumen and in the vicinity of the central vein. A total of 12 isolates of streptococci were obtained from the moribund fish. This study documented the ability of the MicroSeq 500 16S bacterial sequencing method to accurately identify Streptococcus agalactiae and S. dysgalactiae mixed infections from moribund red tilapia that were difficult to be recognised by the commercial biochemical systems. The continuously decreasing cost of the sequencing technique should encourage its application in routine diagnostic procedures.

  20. Pathogenic Yersinia enterocolitica O:3 isolated from a hunted wild alpine ibex.

    Science.gov (United States)

    Joutsen, S; Sarno, E; Fredriksson-Ahomaa, M; Cernela, N; Stephan, R

    2013-03-01

    Occurrence of Yersinia spp. in wild ruminants was studied and the strains were characterized to get more information on the epidemiology of enteropathogenic Yersinia in the wildlife. In total, faecal samples of 77 red deer, 60 chamois, 55 roe deer and 27 alpine ibex were collected during 3 months of the hunting season in 2011. The most frequently identified species was Y. enterocolitica found in 13%, 10%, 4% and 2% of roe deer, red deer, alpine ibex and chamois, respectively. Interestingly, one Y. enterocolitica O:3 strain, isolated from an alpine ibex, carried the important virulence genes located on the virulence plasmid (yadA and virF) and in the chromosome (ail, hreP, myfA and ystA). Most of the Y. enterocolitica strains belonged to biotype 1A of which 14 were ystB positive. Further studies are needed to clarify the importance of alpine ibex as a reservoir of pathogenic Y. enterocolitica.

  1. The isolation and identification of pathogenic fungi from Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae

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    Xiang Meng

    2017-10-01

    Full Text Available Background Litchi stink-bug, Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae, is one of the most widespread and destructive pest species on Litchi chinensis Sonn and Dimocarpus longan Lour in Southern China. Inappropriate use of chemical pesticides has resulted in serious environmental problems and food pollution. Generating an improved Integrated Pest Management (IPM strategy for litchi stink-bug in orchard farming requires development of an effective biological control agent. Entomopathogenic fungi are regarded as a vital ecological factor in the suppression of pest populations under field conditions. With few effective fungi and pathogenic strains available to control litchi stink-bug, exploration of natural resources for promising entomopathogenic fungi is warranted. Methods & Results In this study, two pathogenic fungi were isolated from cadavers of adult T. papillosa. They were identified as Paecilomyces lilacinus and Beauveria bassiana by morphological identification and rDNA-ITS homogeneous analysis. Infection of T. papillosa with B. bassiana and P. lilacinus occurred initially from the antennae, metameres, and inter-segmental membranes. Biological tests showed that the two entomopathogenic fungi induced high mortality in 2nd and 5th instar nymphs of T. papillosa. B. bassiana was highly virulent on 2nd instar nymphs of T. papillosa, with values for cadaver rate, LC50 and LT50 of 88.89%, 1.92 × 107 conidia/mL and 4.34 days respectively. Discussion This study provides two valuable entomopathogenic fungi from T. papillosa. This finding suggests that the highly virulent P. lilacinus and B. bassiana play an important role in the biocontrol of T. papillosa in China. These pathogenic fungi had no pollution or residue risk, and could provide an alternative option for IPM of litchi stink-bug.

  2. The isolation and identification of pathogenic fungi from Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae).

    Science.gov (United States)

    Meng, Xiang; Hu, Junjie; Ouyang, Gecheng

    2017-01-01

    Litchi stink-bug, Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae), is one of the most widespread and destructive pest species on Litchi chinensis Sonn and Dimocarpus longan Lour in Southern China. Inappropriate use of chemical pesticides has resulted in serious environmental problems and food pollution. Generating an improved Integrated Pest Management (IPM) strategy for litchi stink-bug in orchard farming requires development of an effective biological control agent. Entomopathogenic fungi are regarded as a vital ecological factor in the suppression of pest populations under field conditions. With few effective fungi and pathogenic strains available to control litchi stink-bug, exploration of natural resources for promising entomopathogenic fungi is warranted. In this study, two pathogenic fungi were isolated from cadavers of adult T. papillosa . They were identified as Paecilomyces lilacinus and Beauveria bassiana by morphological identification and rDNA-ITS homogeneous analysis. Infection of T. papillosa with B. bassiana and P. lilacinus occurred initially from the antennae, metameres, and inter-segmental membranes. Biological tests showed that the two entomopathogenic fungi induced high mortality in 2 nd and 5 th instar nymphs of T. papillosa . B. bassiana was highly virulent on 2 nd instar nymphs of T. papillosa , with values for cadaver rate, LC 50 and LT 50 of 88.89%, 1.92 × 10 7  conidia/mL and 4.34 days respectively. This study provides two valuable entomopathogenic fungi from T. papillosa . This finding suggests that the highly virulent P. lilacinus and B. bassiana play an important role in the biocontrol of T. papillosa in China. These pathogenic fungi had no pollution or residue risk, and could provide an alternative option for IPM of litchi stink-bug.

  3. Potential probiotic characteristics of Lactobacillus and Enterococcus strains isolated from traditional dadih fermented milk against pathogen intestinal colonization.

    Science.gov (United States)

    Collado, M Carmen; Surono, Ingrid S; Meriluoto, Jussi; Salminen, Seppo

    2007-03-01

    Traditional fermented buffalo milk in Indonesia (dadih) has been believed to have a beneficial impact on human health, which could be related to the properties of the lactic acid bacteria (LAB) involved in its fermentation process. In previous studies, it was discovered that strains of dadih lactic isolates possessed some beneficial properties in vitro. In the present study, the adhesion capacity of specific LAB isolates from dadih to intestinal mucus was analyzed. Further, the ability to inhibit model human pathogens and displace them from mucus was assessed. The adhesion of tested LAB strains was strain-dependent and varied from 1.4 to 9.8%. The most adhesive Lactobacillus plantarum strain was IS-10506, with 9.8% adhesion. The competition assay between dadih LAB isolates and pathogens showed that a 2-h preincubation with L. plantarum at 37 degrees C significantly reduced pathogen adhesion to mucus. All tested LAB strains displaced and inhibited pathogen adhesion, but the results were strain-specific and dependent on time and pathogen strains. In general, L. plantarum IS-10506 showed the best ability against pathogen adhesion.

  4. Effect of medicinal plants, Heavy metals and antibiotics against pathogenic bacteria isolated from raw, Boiled and pasteurized milk.

    Science.gov (United States)

    Ali, Nazish Mazhar; Sarwar, Khadija; Mazhar, Syed Abdullah; Liaqat, Iram; Andleeb, Saiqa; Mazhar, Bushra; Kalim, Bushra

    2017-11-01

    Present study has been undertaken to isolate and identify the bacterial flora in raw, boiled and pasteurized milk. Agar disc diffusion method was used to determine their sensitivity using medicinal plants, antibiotics and heavy metals. Methylene blue reduction test was used to test the quality of milk samples. Total 10 pathogenic strains were isolated, five strains were isolated from raw milk, three from boiled milk and 2 two from pasteurized milk. To determine optimum conditions for growth, these pathogenic microorganisms were incubated at various temperatures and pH. Gram's staining and biochemical tests revealed that these pathogenic bacteria include Lactobacillus sp., E. coli, Salmonella sp., Pseudomonas sp., Streptococcus sp. and Staphylococcus. Ribotyping revealed S2 as Pseudomonas fluorescens, S5 as Lactococcus lactis and S9 as Lactobacillus acidophilus. Prevalence of pathogenic organisms provided the evidence that contamination of milk arises during milking, transportation and storage of milk. Raw milk is more contaminated than other two types of milk because it contains highest percentage of pathogenic organisms and pasteurized milk was found to be of best quality among three types. So it is recommended to drink milk after proper boiling or pasteurization. Proper pasteurization and hygienic packing of milk is essential to minimize contamination in milk which can save human beings from many milk borne diseases. Our study suggests that antimicrobial use in animal husbandry should be minimized to reduce the hazard of antibiotic resistance. Plant extracts are better alternative against pathogenic bacteria in milk.

  5. Isolation of recombinant phage antibodies targeting the hemagglutinin cleavage site of highly pathogenic avian influenza virus.

    Directory of Open Access Journals (Sweden)

    Jinhua Dong

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 viruses, which have emerged in poultry and other wildlife worldwide, contain a characteristic multi-basic cleavage site (CS in the hemagglutinin protein (HA. Because this arginine-rich CS is unique among influenza virus subtypes, antibodies against this site have the potential to specifically diagnose pathogenic H5N1. By immunizing mice with the CS peptide and screening a phage display library, we isolated four antibody Fab fragment clones that specifically bind the antigen peptide and several HPAI H5N1 HA proteins in different clades. The soluble Fab fragments expressed in Escherichia coli bound the CS peptide and the H5N1 HA protein with nanomolar affinity. In an immunofluorescence assay, these Fab fragments stained cells infected with HPAI H5N1 but not those infected with a less virulent strain. Lastly, all the Fab clones could detect the CS peptide and H5N1 HA protein by open sandwich ELISA. Thus, these recombinant Fab fragments will be useful novel reagents for the rapid and specific detection of HPAI H5N1 virus.

  6. An evaluation of indices for quantifying tuberculosis transmission using genotypes of pathogen isolates

    Directory of Open Access Journals (Sweden)

    Phong Renault

    2006-06-01

    Full Text Available Abstract Background Infectious diseases are often studied by characterising the population structure of the pathogen using genetic markers. An unresolved problem is the effective quantification of the extent of transmission using genetic variation data from such pathogen isolates. Methods It is important that transmission indices reflect the growth of the infectious population as well as account for the mutation rate of the marker and the effects of sampling. That is, while responding to this growth rate, indices should be unresponsive to the sample size and the mutation rate. We use simulation methods taking into account both the mutation and sampling processes to evaluate indices designed to quantify transmission of tuberculosis. Results Previously proposed indices generally perform inadequately according to the above criteria, with the partial exception of the recently proposed Transmission-Mutation Index. Conclusion Any transmission index needs to take into account mutation of the marker and the effects of sampling. Simple indices are unlikely to capture the full complexity of the underlying processes.

  7. Comparison of the pathogenicity of Nipah virus isolates from Bangladesh and Malaysia in the Syrian hamster.

    Directory of Open Access Journals (Sweden)

    Blair L DeBuysscher

    Full Text Available Nipah virus is a zoonotic pathogen that causes severe disease in humans. The mechanisms of pathogenesis are not well described. The first Nipah virus outbreak occurred in Malaysia, where human disease had a strong neurological component. Subsequent outbreaks have occurred in Bangladesh and India and transmission and disease processes in these outbreaks appear to be different from those of the Malaysian outbreak. Until this point, virtually all Nipah virus studies in vitro and in vivo, including vaccine and pathogenesis studies, have utilized a virus isolate from the original Malaysian outbreak (NiV-M. To investigate potential differences between NiV-M and a Nipah virus isolate from Bangladesh (NiV-B, we compared NiV-M and NiV-B infection in vitro and in vivo. In hamster kidney cells, NiV-M-infection resulted in extensive syncytia formation and cytopathic effects, whereas NiV-B-infection resulted in little to no morphological changes. In vivo, NiV-M-infected Syrian hamsters had accelerated virus replication, pathology and death when compared to NiV-B-infected animals. NiV-M infection also resulted in the activation of host immune response genes at an earlier time point. Pathogenicity was not only a result of direct effects of virus replication, but likely also had an immunopathogenic component. The differences observed between NiV-M and NiV-B pathogeneis in hamsters may relate to differences observed in human cases. Characterization of the hamster model for NiV-B infection allows for further research of the strain of Nipah virus responsible for the more recent outbreaks in humans. This model can be used to study NiV-B pathogenesis, transmission, and countermeasures that could be used to control outbreaks.

  8. Antimicrobial and antibiofilm potential of biosurfactants isolated from lactobacilli against multi-drug-resistant pathogens

    Science.gov (United States)

    2014-01-01

    Background Biosurfactants (BS) are amphiphilic compounds produced by microbes, either on the cell surface or secreted extracellularly. BS exhibit strong antimicrobial and anti-adhesive properties, making them good candidates for applications used to combat infections. In this study, our goal was to assess the in vitro antimicrobial, anti-adhesive and anti-biofilm abilities of BS produced by Lactobacillus jensenii and Lactobacillus rhamnosus against clinical Multidrug Resistant (MDR) strains of Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus (MRSA). Cell-bound BS from both L. jensenii and L. rhamnosus were extracted and isolated. The surface activities of crude BS samples were evaluated using an oil spreading assay. The antimicrobial, anti-adhesive and anti-biofilm activities of both BS against the above mentioned MDR pathogens were determined. Results Surface activities for both BS ranged from 6.25 to 25 mg/ml with clear zones observed between 7 and 11 cm. BS of both L. jensenii and L. rhamnosus showed antimicrobial activities against A. baumannii, E. coli and S. aureus at 25-50 mg/ml. Anti-adhesive and anti-biofilm activities were also observed for the aforementioned pathogens between 25 and 50 mg/ml. Finally, analysis by electron microscope indicated that the BS caused membrane damage for A. baumannii and pronounced cell wall damage in S. aureus. Conclusion Our results indicate that BS isolated from two Lactobacilli strains has antibacterial properties against MDR strains of A. baumannii, E. coli and MRSA. Both BS also displayed anti-adhesive and anti-biofilm abilities against A. baumannii, E. coli and S. aureus. Together, these capabilities may open up possibilities for BS as an alternative therapeutic approach for the prevention and/or treatment of hospital-acquired infections. PMID:25124936

  9. Detection of virulence-associated genes in pathogenic and commensal avian Escherichia coli isolates.

    Science.gov (United States)

    Paixão, A C; Ferreira, A C; Fontes, M; Themudo, P; Albuquerque, T; Soares, M C; Fevereiro, M; Martins, L; Corrêa de Sá, M I

    2016-07-01

    Poultry colibacillosis due to Avian Pathogenic Escherichia coli (APEC) is responsible for several extra-intestinal pathological conditions, leading to serious economic damage in poultry production. The most commonly associated pathologies are airsacculitis, colisepticemia, and cellulitis in broiler chickens, and salpingitis and peritonitis in broiler breeders. In this work a total of 66 strains isolated from dead broiler breeders affected with colibacillosis and 61 strains from healthy broilers were studied. Strains from broiler breeders were typified with serogroups O2, O18, and O78, which are mainly associated with disease. The serogroup O78 was the most prevalent (58%). All the strains were checked for the presence of 11 virulence genes: 1) arginine succinyltransferase A (astA); ii) E.coli hemeutilization protein A (chuA); iii) colicin V A/B (cvaA/B); iv) fimbriae mannose-binding type 1 (fimC); v) ferric yersiniabactin uptake A (fyuA); vi) iron-repressible high-molecular-weight proteins 2 (irp2); vii) increased serum survival (iss); viii) iron-uptake systems of E.coli D (iucD); ix) pielonefritis associated to pili C (papC); x) temperature sensitive haemaglutinin (tsh), and xi) vacuolating autotransporter toxin (vat), by Multiplex-PCR. The results showed that all genes are present in both commensal and pathogenic E. coli strains. The iron uptake-related genes and the serum survival gene were more prevalent among APEC. The adhesin genes, except tsh, and the toxin genes, except astA, were also more prevalent among APEC isolates. Except for astA and tsh, APEC strains harbored the majority of the virulence-associated genes studied and fimC was the most prevalent gene, detected in 96.97 and 88.52% of APEC and AFEC strains, respectively. Possession of more than one iron transport system seems to play an important role on APEC survival. © 2016 Poultry Science Association Inc.

  10. Simulation of enteric pathogen concentrations in locally-collected greywater and wastewater for microbial risk assessments

    Science.gov (United States)

    As decentralized water reuse continues to gain popularity, risk-based treatment guidance is increasingly sought for the protection of public health. However, efforts to evaluate pathogen risks and log-reduction requirements have been hindered by an incomplete understanding of pat...

  11. Microbial pathogens in source and treated waters from drinking water treatment plants in the US

    Science.gov (United States)

    An occurrence survey was conducted on selected pathogens in source and treated drinking water collected from 25 drinking water treatment plants (DWTPs) in the United States. Water samples were analyzed for the protozoa Giardia and Cryptosporidium (EPA Method 1623); the fungi Asp...

  12. Microbial Biosensor for the Detection of Protease-Virulent Factors from Pathogens

    Science.gov (United States)

    2017-04-28

    pathogen signalling molecules. With that goal in mind , researchers have developed various types of biosensors that detect infectious determinants...life to boost their capability for rapid determination of clean water sources during field deployment. Despite the promising results of these studies

  13. Correlations between Microbial Indicators, Pathogens, and Environmental Factors in a Subtropical Estuary

    Science.gov (United States)

    Ortega, Cristina; Solo-Gabriele, Helena M.; Abdelzaher, Amir; Wright, Mary; Deng, Yang; Stark, Lillian M.

    2009-01-01

    The objective of this study was to evaluate whether indicator microbes and physical-chemical parameters were correlated with pathogens within a tidally influenced estuary. Measurements included the analysis of physical-chemical parameters (pH, salinity, temperature, and turbidity), measurements of bacterial indicators (enterococci, fecal coliform, E. coli, and total coliform), viral indicators (somatic and MS2 coliphage), viral pathogens (enterovirus by culture), and protozoan pathogens (Cryptosporidium and Giardia). All pathogen results were negative with the exception of one sample which tested positive for culturable reovirus (8.5 MPN/100 L).. Notable physical-chemical parameters for this sample included low salinity (<1 ppt) and high water temperature (31 °C). Indicator bacteria and indicator virus levels for this sample were within average values typically measured within the study site and were low in comparison with levels observed in other freshwater environments. Overall results suggest that high levels of bacterial and viral indicators were associated with low salinity sites. PMID:19464704

  14. Pathogenic bacteria and microbial-source tracking markers in Brandywine Creek Basin, Pennsylvania and Delaware, 2009-10

    Science.gov (United States)

    Duris, Joseph W.; Reif, Andrew G.; Olson, Leif E.; Johnson, Heather E.

    2011-01-01

    virulent type of pathogenic E. coli, was found only in the West Branch and main stem at high flow but was not found in the East Branch under similar conditions. However, it must be noted that throughout the entire year of sampling there were occasions, during both high and normal flows, when both the East and West Branches were potential contributors of pathogen and microbial-source tracking markers to the main stem. Therefore, this study indicates that under selected conditions (high flow, October through March), West Branch Brandywine Creek Basin was the most likely source of elevated FIB densities in the main stem. These elevated densities are associated with more frequent detection of selected pathogenic E. coli markers (rfbO157 stx1) and are associated with MST markers of bovine source. However, during other times of the year, both the West Branch and East Branch Basins are acting as potential sources of FIB and fecally derived pathogens.

  15. Determination of human pathogen profiles in food by quality assured microbial assays. Proceedings of a final Research Coordination Meeting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-01-15

    This publication includes the results of a Coordinated Research Project (CRP). Major food microbial contaminants were identified in some of the main foods exported in the international food market. Thousands of samples in a wide variety of foods were selected to be studied during different points of the food chain: meat (chicken, beef and pork), seafood (shellfish such as shrimp, prawns, scampi, squid, and lobsters, and different types of fish such as salmon, cuttle fish, rohu, fin herring, catfish, milkfish, and tilapia), spices (pepper, paprika), frozen vegetables (asparagus, peas and corn) and other products (coconut and dairy products). The analysis included pathogenic bacteria such as Salmonella spp. (several serotypes), Escherichia coli, E. coli 0157:H7, Staphylococcus aureus, Clostridium perfringens, Bacillus cereus, Vibrio choleare, Vibrio parahaemolitycus and Yersinia enterolítica. This publication includes data that may be used to conduct better risk assessments on food by importing as well as exporting countries.

  16. Molecular methods for pathogen and microbial community detection and characterization: current and potential application in diagnostic microbiology.

    Science.gov (United States)

    Sibley, Christopher D; Peirano, Gisele; Church, Deirdre L

    2012-04-01

    Clinical microbiology laboratories worldwide have historically relied on phenotypic methods (i.e., culture and biochemical tests) for detection, identification and characterization of virulence traits (e.g., antibiotic resistance genes, toxins) of human pathogens. However, limitations to implementation of molecular methods for human infectious diseases testing are being rapidly overcome allowing for the clinical evaluation and implementation of diverse technologies with expanding diagnostic capabilities. The advantages and limitation of molecular techniques including real-time polymerase chain reaction, partial or whole genome sequencing, molecular typing, microarrays, broad-range PCR and multiplexing will be discussed. Finally, terminal restriction fragment length polymorphism (T-RFLP) and deep sequencing are introduced as technologies at the clinical interface with the potential to dramatically enhance our ability to diagnose infectious diseases and better define the epidemiology and microbial ecology of a wide range of complex infections. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. The in vitro culture of Phytophthora infestans isolates occurring on the tomato - their pathogenicity and usefulness for artificial inoculations

    Directory of Open Access Journals (Sweden)

    Elżbieta Horodecka

    2013-12-01

    Full Text Available In investigations on the fungus, Phytophthora infestans, isolated from open air, field-grown tomatoes, particular attention was paid to the pathogenicity of 32 isolates and the suitability of 10 kinds of natural media. It is concluded that Phytophthora races in Poland have highly varied pathogenicities and that they belong to race 0 or 1. The races were divided into subgroups of various aggressiveness. It was found that the best medium to obtain an inoculum was the agar-oat medium without vitamin B1. Vitamin B1 as well as tomatine added to agar media stimulated growth, but inhibited sporulation of Phytophthora infestans.

  18. Molecular characterization of double-stranded RNA virus in Trichomonas vaginalis Egyptian isolates and its association with pathogenicity.

    Science.gov (United States)

    El-Gayar, Eman K; Mokhtar, Amira B; Hassan, Wael A

    2016-10-01

    Trichomoniasis is a common human sexually transmitted infection caused by Trichomonas vaginalis. The parasite can be infected with double-stranded RNA viruses (TVV). This viral infection may have important implications on trichomonal virulence and disease pathogenesis. This study aimed to determine the prevalence of T. vaginalis virus among isolates obtained from infected (symptomatic and asymptomatic) women in Ismailia City, Egypt, and to correlate the virus-infected isolates with the clinical manifestations of patients. In addition, the pathogenicity of TVV infected isolates on mice was also evaluated. T. vaginalis isolates were obtained from symptomatic and asymptomatic female patients followed by axenic cultivation in Diamond's TYM medium. The presence of T. vaginalis virus was determined from total extraction of nucleic acids (DNA-RNA) followed by reverse transcriptase-PCR. Representative samples were inoculated intraperitoneally in female albino/BALB mice to assess the pathogenicity of different isolates. A total of 110 women were examined; 40 (36.3 %) samples were positive for T. vaginalis infection. Of these 40 isolates, 8 (20 %) were infected by TVV. Five isolates contained TVV-2 virus species, and the remaining three isolates were infected withTVV-4 variant. A significant association was found between the presence of TVV and particular clinical manifestations of trichomoniasis. Experimental mice infection showed varying degrees of pathogenicity. This is the first report on T. vaginalis infection by TVV in Egypt. The strong association detected between TVV and particular clinical features of trichomoniasis and also the degree of pathogenicity in experimentally infected mice may indicate a possible clinical significance of TVV infection of T. vaginalis isolates.

  19. The Effectiveness of Heterotrophic Bacteria Isolated from Dumai Marine Waters of Riau, Used as Antibacterial against Pathogens in Fish Culture

    Science.gov (United States)

    Feliatra, F.; Nursyirwani; Tanjung, A.; Adithiya, DS; Susanna, M.; Lukystyowati, I.

    2018-02-01

    Heterotrophic bacteria have an important role as decomposer of organic compounds (mineralization) derived from industrial waste, decomposition of unconsumed feed, faecal, excretion of fish, and have the ability to inhibit the growth of pathogenic bacteria. We investigated the role of heterotrophic bacteria used as antibacterial against pathogens in fish culture.This research was conducted from January until March 2017. The phylogenitic of the isolated bacterial was determined by 16S rDNA sequences analysis. Antagonism test showed that the bacteria had the ability to inhibit the growth of pathogenic bacteria (Vibrio alginolyticus, Aeromonas hydrophila and Pseudomonas sp.) Three isolates (Dm5, Dm6 and Dm4) indicated high inhibition zones which were classified into strong category with the average from 10.5 to 11.8 mm toward V. alginolitycus. Other isolates were classified into medium and weak category. Based on DNA analysis of heterotrophic bacteria isolated from marine waters of industrial area and low salinity of estuarine waters twelve strains of bacteria were identified, and all had highest level of homology to Bacillus sp.,one isolates has similarity to Enterobacter cloacae, other isolates to Clostridium cetobutylicum. Most of isolated bacteria obtained from the waters of industrial area due to it received much of nutrients that very influenced the growth of bacteria.

  20. Enhancement of microbial quality and inactivation of pathogenic bacteria by gamma irradiation of ready-to-cook Iranian barbecued chicken

    Science.gov (United States)

    Fallah, Aziz A.; Siavash Saei-Dehkordi, S.; Rahnama, Mohammad

    2010-10-01

    Ready-to-cook Iranian barbecued chicken consists of cubed chicken breast, lemon juice, salt, red pepper, onion, saffron and vegetable oil with an overall pH value of about 5.5. This product is sometimes consumed under-cooked, hence it may pose health hazards to consumers when contaminated with food-borne pathogens. In this study, the effect of gamma irradiation (0, 1.5, 3 and 4.5 kGy) on the microbial quality of ready-to-cook (RTC) barbecued chicken samples stored at 4 °C for 15 days was investigated. Moreover, the effectiveness of irradiation for inactivating Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella typhimurium inoculated into the samples was also studied. Irradiation of the samples resulted in dose dependent reduction in counts of aerobic mesophilic bacteria, yeasts and molds, Enterobacteriaceae and lactic acid bacteria. Among the microbial flora, yeasts and molds and Enterobacteriaceae were more sensitive to irradiation and got completely eliminated at dose of 3 kGy. D10 values of L. monocytogenes, E. coli O157:H7 and S. typhimurium inoculated into the samples were 0.680, 0.397 and 0.601 kGy, respectively. An irradiation dose of 3 kGy reduced the counts of E. coli O157:H7 to an undetectable level in RTC barbecued chicken but was ineffective on elimination of L. monocytogenes and S. typhimurium. However, none of the food-borne pathogens were detected in the samples irradiated at 4.5 kGy. This study showed that irradiation had no undesirable effects on the initial sensory attributes of barbecued chicken. At the end of the storage period, irradiated samples were more acceptable compared to non-irradiated ones.

  1. Enhancement of microbial quality and inactivation of pathogenic bacteria by gamma irradiation of ready-to-cook Iranian barbecued chicken

    International Nuclear Information System (INIS)

    Fallah, Aziz A.; Siavash Saei-Dehkordi, S.; Rahnama, Mohammad

    2010-01-01

    Ready-to-cook Iranian barbecued chicken consists of cubed chicken breast, lemon juice, salt, red pepper, onion, saffron and vegetable oil with an overall pH value of about 5.5. This product is sometimes consumed under-cooked, hence it may pose health hazards to consumers when contaminated with food-borne pathogens. In this study, the effect of gamma irradiation (0, 1.5, 3 and 4.5 kGy) on the microbial quality of ready-to-cook (RTC) barbecued chicken samples stored at 4 o C for 15 days was investigated. Moreover, the effectiveness of irradiation for inactivating Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella typhimurium inoculated into the samples was also studied. Irradiation of the samples resulted in dose dependent reduction in counts of aerobic mesophilic bacteria, yeasts and molds, Enterobacteriaceae and lactic acid bacteria. Among the microbial flora, yeasts and molds and Enterobacteriaceae were more sensitive to irradiation and got completely eliminated at dose of 3 kGy. D 10 values of L. monocytogenes, E. coli O157:H7 and S. typhimurium inoculated into the samples were 0.680, 0.397 and 0.601 kGy, respectively. An irradiation dose of 3 kGy reduced the counts of E. coli O157:H7 to an undetectable level in RTC barbecued chicken but was ineffective on elimination of L. monocytogenes and S. typhimurium. However, none of the food-borne pathogens were detected in the samples irradiated at 4.5 kGy. This study showed that irradiation had no undesirable effects on the initial sensory attributes of barbecued chicken. At the end of the storage period, irradiated samples were more acceptable compared to non-irradiated ones.

  2. Enhancement of microbial quality and inactivation of pathogenic bacteria by gamma irradiation of ready-to-cook Iranian barbecued chicken

    Energy Technology Data Exchange (ETDEWEB)

    Fallah, Aziz A., E-mail: a_a_falah@yahoo.co [Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Shahre-Kord University, Shahre-Kord 34141 (Iran, Islamic Republic of); Research Institute of Zoonotic Diseases, Shahre-Kord University, Shahre-Kord 34141 (Iran, Islamic Republic of); Siavash Saei-Dehkordi, S. [Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Shahre-Kord University, Shahre-Kord 34141 (Iran, Islamic Republic of); Research Institute of Zoonotic Diseases, Shahre-Kord University, Shahre-Kord 34141 (Iran, Islamic Republic of); Rahnama, Mohammad [Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, University of Zabol, Zabol 98615 (Iran, Islamic Republic of)

    2010-10-15

    Ready-to-cook Iranian barbecued chicken consists of cubed chicken breast, lemon juice, salt, red pepper, onion, saffron and vegetable oil with an overall pH value of about 5.5. This product is sometimes consumed under-cooked, hence it may pose health hazards to consumers when contaminated with food-borne pathogens. In this study, the effect of gamma irradiation (0, 1.5, 3 and 4.5 kGy) on the microbial quality of ready-to-cook (RTC) barbecued chicken samples stored at 4 {sup o}C for 15 days was investigated. Moreover, the effectiveness of irradiation for inactivating Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella typhimurium inoculated into the samples was also studied. Irradiation of the samples resulted in dose dependent reduction in counts of aerobic mesophilic bacteria, yeasts and molds, Enterobacteriaceae and lactic acid bacteria. Among the microbial flora, yeasts and molds and Enterobacteriaceae were more sensitive to irradiation and got completely eliminated at dose of 3 kGy. D{sub 10} values of L. monocytogenes, E. coli O157:H7 and S. typhimurium inoculated into the samples were 0.680, 0.397 and 0.601 kGy, respectively. An irradiation dose of 3 kGy reduced the counts of E. coli O157:H7 to an undetectable level in RTC barbecued chicken but was ineffective on elimination of L. monocytogenes and S. typhimurium. However, none of the food-borne pathogens were detected in the samples irradiated at 4.5 kGy. This study showed that irradiation had no undesirable effects on the initial sensory attributes of barbecued chicken. At the end of the storage period, irradiated samples were more acceptable compared to non-irradiated ones.

  3. CheckM: assessing the quality of microbial genomes recovered from isolates, single cells, and metagenomes

    Science.gov (United States)

    Parks, Donovan H.; Imelfort, Michael; Skennerton, Connor T.; Hugenholtz, Philip; Tyson, Gene W.

    2015-01-01

    Large-scale recovery of genomes from isolates, single cells, and metagenomic data has been made possible by advances in computational methods and substantial reductions in sequencing costs. Although this increasing breadth of draft genomes is providing key information regarding the evolutionary and functional diversity of microbial life, it has become impractical to finish all available reference genomes. Making robust biological inferences from draft genomes requires accurate estimates of their completeness and contamination. Current methods for assessing genome quality are ad hoc and generally make use of a limited number of “marker” genes conserved across all bacterial or archaeal genomes. Here we introduce CheckM, an automated method for assessing the quality of a genome using a broader set of marker genes specific to the position of a genome within a reference genome tree and information about the collocation of these genes. We demonstrate the effectiveness of CheckM using synthetic data and a wide range of isolate-, single-cell-, and metagenome-derived genomes. CheckM is shown to provide accurate estimates of genome completeness and contamination and to outperform existing approaches. Using CheckM, we identify a diverse range of errors currently impacting publicly available isolate genomes and demonstrate that genomes obtained from single cells and metagenomic data vary substantially in quality. In order to facilitate the use of draft genomes, we propose an objective measure of genome quality that can be used to select genomes suitable for specific gene- and genome-centric analyses of microbial communities. PMID:25977477

  4. Host-pathogen interactions in bovine mammary epithelial cells and HeLa cells by Staphylococcus aureus isolated from subclinical bovine mastitis.

    Science.gov (United States)

    Castilho, Ivana G; Dantas, Stéfani Thais Alves; Langoni, Hélio; Araújo, João P; Fernandes, Ary; Alvarenga, Fernanda C L; Maia, Leandro; Cagnini, Didier Q; Rall, Vera L M

    2017-08-01

    Staphylococcus aureus is a common pathogen that causes subclinical bovine mastitis due to several virulence factors. In this study, we analyzed S. aureus isolates collected from the milk of cows with subclinical mastitis that had 8 possible combinations of bap, icaA, and icaD genes, to determine their capacity to produce biofilm on biotic (bovine primary mammary epithelial cells and HeLa cells) and abiotic (polystyrene microplates) surfaces, and their ability to adhere to and invade these cells. We also characterized isolates for microbial surface components recognizing adhesive matrix molecules (MSCRAMM) and agr genes, and for their susceptibility to cefquinome sulfate in the presence of biofilm. All isolates adhered to and invaded both cell types, but invasion indexes were higher in bovine primary mammary epithelial cells. Using tryptic soy broth + 1% glucose on abiotic surfaces, 5 out of 8 isolates were biofilm producers, but only the bap + icaA + icaD + isolate was positive in Dulbecco's Modified Eagle's medium. The production of biofilm on biotic surfaces occurred only with this isolate and only on HeLa cells, because the invasion index for bovine primary mammary epithelial cells was too high, making it impossible to use these cells in this assay. Of the 5 biofilm producers in tryptic soy broth + 1% glucose, 4 presented with the bap/fnbA/clfA/clfB/eno/fib/ebpS combination, and all were protected from cefquinome sulfate. We found no predominance of any agr group. The high invasive potential of S. aureus made it impossible to observe biofilm in bovine primary mammary epithelial cells, and we concluded that cells with lower invasion rates, such as HeLa cells, were more appropriate for this assay. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  5. Characterization of the cell surface properties of drinking water pathogens by microbial adhesion to hydrocarbon and electrophoretic mobility measurements.

    Science.gov (United States)

    Popovici, Jonathan; White, Colin P; Hoelle, Jill; Kinkle, Brian K; Lytle, Darren A

    2014-06-01

    The surface characteristics of microbial cells directly influence their mobility and behavior within aqueous environments. The cell surface hydrophobicity (CSH) and electrophoretic mobility (EPM) of microbial cells impact a number of interactions and processes including aggregation, adhesion to surfaces, and stability of the cells within the aqueous environments. These cell characteristics are unique to the bacterial species and are a reflection of the large diversity of surface structures, proteins, and appendages of microorganisms. CSH and EPM of bacterial cells contribute substantially to the effectiveness of drinking water treatment to remove them, and therefore an investigation of these properties will be useful in predicting their removal through drinking water treatment processes and transport through drinking water distribution systems. EPM and CSH measurements of six microbiological pathogen or surrogate species suspended in phosphate-buffered water are reported in this work. Two strains of Vibrio cholerae were hydrophobic, while three strains of Escherichia coli were hydrophilic. Bacillus cereus was categorized as moderately hydrophobic. The strains of E. coli had the highest (most negative) EPM. Based on the measurements, E. coli species is predicted to be most difficult to remove from water while V. cholerae will be the easiest to remove. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Microbial ecology, bacterial pathogens, and antibiotic resistant genes in swine manure wastewater as influenced by three swine management systems.

    Science.gov (United States)

    Brooks, John P; Adeli, Ardeshir; McLaughlin, Michael R

    2014-06-15

    The environmental influence of farm management in concentrated animal feeding operations (CAFO) can yield vast changes to the microbial biota and ecological structure of both the pig and waste manure lagoon wastewater. While some of these changes may not be negative, it is possible that CAFOs can enrich antibiotic resistant bacteria or pathogens based on farm type, thereby influencing the impact imparted by the land application of its respective wastewater. The purpose of this study was to measure the microbial constituents of swine-sow, -nursery, and -finisher farm manure lagoon wastewater and determine the changes induced by farm management. A total of 37 farms were visited in the Mid-South USA and analyzed for the genes 16S rRNA, spaQ (Salmonella spp.), Camp-16S (Campylobacter spp.), tetA, tetB, ermF, ermA, mecA, and intI using quantitative PCR. Additionally, 16S rRNA sequence libraries were created. Overall, it appeared that finisher farms were significantly different from nursery and sow farms in nearly all genes measured and in 16S rRNA clone libraries. Nearly all antibiotic resistance genes were detected in all farms. Interestingly, the mecA resistance gene (e.g. methicillin resistant Staphylococcus aureus) was below detection limits on most farms, and decreased as the pigs aged. Finisher farms generally had fewer antibiotic resistance genes, which corroborated previous phenotypic data; additionally, finisher farms produced a less diverse 16S rRNA sequence library. Comparisons of Camp-16S and spaQ GU (genomic unit) values to previous culture data demonstrated ratios from 10 to 10,000:1 depending on farm type, indicating viable but not cultivatable bacteria were dominant. The current study indicated that swine farm management schemes positively and negatively affect microbial and antibiotic resistant populations in CAFO wastewater which has future "downstream" implications from both an environmental and public health perspective. Published by Elsevier Ltd.

  7. Increased incidence of resistance to antimicrobials by urinary pathogens isolated at Tikur Anbessa Hospital.

    Science.gov (United States)

    Wolday, D; Erge, W

    1997-04-01

    A retrospective analysis of 2209 urine samples submitted for culture to the Microbiology Laboratory of the Tikur Anbessa Hospital (TAH), Addis Ababa, between January 1992 and December 1994 was made. Significant bacteriuria (colony count > 10(5) colony forming units/ml urine) was detected in 672 (30%). Pure culture was obtained in 510 (23%) of all samples and polymicrobial growth was detected in the remaining 162 (7%). Gram-negative bacteria comprised 95% of all isolates. The commonest organisms being Escherichia coli (39%) and Klebsiella species (26%). Among the gram-positives, Staphylococcus aureus (57%) was the most common pathogen isolated. Most of the organisms were resistant to multiple drugs. Ampicillin, carbenicillin, chloramphenicol, tetracycline and trimethoprim-sulphamethoxazole were effective in less than 30% of all cases. There was also a significant resistance to cephalothin, gentamicin and kanamycin. Only nalidixic acid and nitrofurantoin were effective for most of the organisms. Compared to previous studies, there is an indication of reduced effectiveness of the commonly prescribed antibiotics. The rational use of drugs should be practiced in order to prevent the emergence of multi-drug resistant microorganisms.

  8. Comparative genomics of pathogenic Leptospira interrogans serovar Canicola isolated from swine and human in Brazil

    Directory of Open Access Journals (Sweden)

    Luisa Z Moreno

    Full Text Available Leptospira interrogans serovar Canicola is one of the most important pathogenic serovars for the maintenance of urban leptospirosis. Even though it is considered highly adapted to dogs, serovar Canicola infection has already been described in other animals and even a few human cases. Here, we present the genomic characterisation of two Brazilian L. interrogans serovar Canicola strains isolated from slaughtered sows (L0-3 and L0-4 and their comparison with human strain Fiocruz LV133. It was observed that the porcine serovar Canicola strains present the genetic machinery to cause human infection and, therefore, represent a higher risk to public health. Both human and porcine serovar Canicola isolates also presented sequences with high identity to the Chinese serovar Canicola published plasmids pGui1 and pGui2. The plasmids identification in the Brazilian and Chinese serovar Canicola strains suggest that extra-chromosomal elements are one more feature of this serovar that was previously unnoticed.

  9. Characterizing relationships among fecal indicator bacteria, microbial source tracking markers, and associated waterborne pathogen occurrence in stream water and sediments in a mixed land use watershed

    Science.gov (United States)

    Bed sediments of streams and rivers may store high concentrations of fecal indicator bacteria (FIB) and pathogens. Due to resuspension events, these contaminants can be mobilized into the water column and affect overall water quality. Other bacterial indicators such as microbial ...

  10. Phytochemical, toxicological and antimicrobial evaluation of Lawsonia inermis extracts against clinical isolates of pathogenic bacteria.

    Science.gov (United States)

    Gull, Iram; Sohail, Maria; Aslam, Muhammad Shahbaz; Amin Athar, Muhammad

    2013-12-01

    The emerging resistance of pathogen against the currently available antimicrobial agents demands the search of new antimicrobial agents. The use of medicinal plants as natural substitute is the paramount area of research to overwhelm the drug resistance of infectious agents. Scientists have not made enough effort on the evaluation of safety of medicinal plant yet. In the present study antimicrobial activity of Lawsonia inermis is investigated against clinical isolates of seven bacteria including four Gram negative (Escherichia coli, Salmonella typhi, Klebsiella spp., Shigella sonnei) and three Gram positive (Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis) using disc diffusion method. Four types of Lawsonia inermis extracts were prepared using methanol, chloroform, acetone and water as extraction solvents, while DMSO (Dimethyl sulfoxide) and water as dissolution solvents. The rate and extent of bacterial killing was estimated by time-kill kinetic assay at 1× MIC of each bacterial isolate. The overall safety of Lawsonia inermis extracts was assessed in mice. Lawsonia inermis displayed noteworthy antimicrobial activity against both gram positive and gram negative bacterial strains used in the study. The minimum value of MIC for different bacterial strains ranged from 2.31 mg/ml to 9.27 mg/ml. At 1x MIC of each bacterial isolate, 3log10 decrease in CFU was recorded after 6 hours of drug exposure and no growth was observed in almost all tested bacteria after 24 hours of exposure. No sign of toxidrome were observed during in vivo toxicity evaluation in mice at 300 mg/kg concentration. In conclusion, the present study provides the scientific rational for medicinal use of Lawsonia inermis. The use of Lawsonia inermis extracts is of great significance as substitute antimicrobial agent in therapeutics.

  11. Isolation and Identification of Pathogenic Fungi from Thorns and Thistles in Isfahan and Adjacent Cities

    Directory of Open Access Journals (Sweden)

    M Emami

    2007-12-01

    Full Text Available Introduction: The most important subcutaneous fungal infections in man are caused by injury due to contaminated thistles and thorns. From an epidemiological point of view , it is important to recognize the fungi as well as their frequency of them in various thistles and thorns Methods: The present research has been conducted on thorns and thistles of 16 regions including cities and villages of Isfahan province. 800 samples have been collected. Specimens were inoculated and incubated at 25◦C in S & SCC medium. In order to isolate and identify the fungi, cultures in specific media, intraperitoneal injections of mice and disc diffusion test have been applied. Results: Over one year of study, 1676 colonies of actinomycetes and fungi were recognized. The most common fungi were as follows: Alternaria (22/4%,Aspergillus(11/8% , Cladosporium (10/8%,Esteril mycellium(10/6% and Penicillium (9/7%. The prevalence was most in Shahreza city(10/2% , while the least was in Ardestan(3%. The most prevalent yeasts were Candida tropicalis (50% , Rodotrula rubra (12/5% , Candida kerusei(11/4%,Trichosporon candida (7/9% , Unknown yeasts (6/8%, Candida gillermondi (5/7%, Saccharomyces cervisia (3/4%, Geotricum candidum and Trichosporon glabrata (Candida glabrata each one (1/1%. The prevalence was most in Khansar city(19/2%. In this study, 4 species similar to Coccidioides immitis, Phialophora verrucosa (4 species and Exophiala jeanselmei (3 species were identified. Conclusion: In this study done for the first time in this area, pathogenic and opportunistic fungi were isolated. Furthermore, Exophiala jeanselmei and Nocardiopsis dassonvillei were isolated for the first time from thorns in the country.

  12. Electricity Generation in Microbial Fuel Cell (MFC) by Bacterium Isolated from Rice Paddy Field Soil

    Science.gov (United States)

    Fakhirruddin, Fakhriah; Amid, Azura; Salim, Wan Wardatul Amani Wan; Suhaida Azmi, Azlin

    2018-03-01

    Microbial fuel cell (MFC) is an alternative approach in generating renewable energy by utilising bacteria that will oxidize organic or inorganic substrates, producing electrons yielded as electrical energy. Different species of exoelectrogenic bacteria capable of generating significant amount of electricity in MFC has been identified, using various organic compounds for fuel. Soil sample taken from rice paddy field is proven to contain exoelectrogenic bacteria, thus electricity generation using mixed culture originally found in the soil, and pure culture isolated from the soil is studied. This research will isolate the exoelectrogenic bacterial species in the rice paddy field soil responsible for energy generation. Growth of bacteria isolated from the MFC is observed by measuring the optical density (OD), cell density weight (CDW) and viable cell count. Mixed bacterial species found in paddy field soil generates maximum power of 77.62 μW and 0.70 mA of current. In addition, the research also shows that the pure bacterium in rice paddy field soil can produce maximum power and current at 51.32 μW and 0.28 mA respectively.

  13. Whey protein isolate edible films with essential oils incorporated to improve the microbial quality of poultry.

    Science.gov (United States)

    Fernández-Pan, Idoya; Mendoza, Mauricio; Maté, Juan I

    2013-09-01

    Whey protein isolate edible films with oregano or clove essential oils (EOs) incorporated as natural antimicrobials have been developed, with the aim of enhancing the microbial quality of poultry. The effectiveness of the films was determined against both the whole and selected microbiota developed during different periods of cold storage on the surface of skinless chicken breast. Tests were conducted by using both turbidimetric and agar disc diffusion methods. The antimicrobial edible films developed showed high effectiveness against the main spoilers developed on the surface of skinless chicken breasts cold-stored for 8 days. The films based on oregano EO showed greater effectiveness than those based on clove EO. Still, clove EO could be part of an effective antimicrobial edible film. Enterobacteriaceae was the most susceptible to the effect of the films when lower concentrations of EO were incorporated. The largest inhibition surfaces obtained were provoked by films with the highest concentration of oregano EO incorporated against lactic acid bacteria. The antimicrobial edible films developed in this study inhibited the growth of the microbial populations that developed through storage of the chicken breast and caused its spoilage. The results of this research have direct application in the food industry to enhance the control of the development of spoilers such as Pseudomonas spp. or lactic acid bacteria. © 2013 Society of Chemical Industry.

  14. Prevalence and Antibiotic Resistance of Gram-Negative Pathogenic Bacteria Species Isolated from Periplaneta americana and Blattella germanica in Varanasi, India.

    Directory of Open Access Journals (Sweden)

    D Leshan Wannigama

    2014-06-01

    Full Text Available Cockroaches are among the medically important pests found within the human habitations that cause serious public health problems. They may harbor a number of pathogenic bacteria on the external surface with antibiotic resistance. Hence, they are regarded as major microbial vectors. This study investigates the prevalence and antibiotic resistance of Gram-negative pathogenic bacteria species isolated from Periplaneta americana and Blattella germanica in Varanasi, India.Totally, 203 adult cockroaches were collected form 44 households and 52 food-handling establishments by trapping. Bacteriological examination of external surfaces of Pe. americana and Bl. germanica were carried out using standard method and antibiotics susceptibility profiles of the isolates were determined using Kirby-Bauer disc diffusion methods.Among the places, we found that 54% had cockroache infestation in households and 77% in food- handling establishments. There was no significant different between the overall bacteria load of the external surface in Pe. americana (64.04% and Bl. germanica (35.96%. However the predominant bacteria on cockroaches were Klebsiella pneumonia, Escherichia coli, Enterobacter aerogenes, and Pseudomonas aeruginosa. However, Kl. pneumoniae and Ps. aeruginosa were the most prevalent, drug-resistant strains were isolated from the cockroaches with 100% resistance to sulfamethoxazole/trimethoprim and ampicillin. For individual strains of bacteria, Escherichia coli was found to have multi-resistance to four antibiotic tested, Citrobacter freundii four, Enterobacter aerogenes and Proteus mirabilis to three.Cockroaches are uniformly distributed in domestic environment, which can be a possible vector for transmission of drug-resistant bacteria and food-borne diseases.

  15. Isolation, antibiogram and pathogenicity of Salmonella spp. Recovered from slaughtered food animals in Nagpur region of Central India

    Directory of Open Access Journals (Sweden)

    D. G. Kalambhe

    2016-02-01

    Full Text Available Aim: To determine the prevalence, antibiogram and pathogenicity of Salmonella spp. in the common food animals slaughtered for consumption purpose at government approved slaughter houses located in and around Nagpur region during a period of 2010-2012. Materials and Methods: A total of 400 samples comprising 50 each of blood and meat from each slaughtered male cattle, buffaloes, pigs and goats were collected. Isolation was done by pre-enrichment in buffered peptone water and enrichment in Rappaport-Vassiliadis broth with subsequent selective plating onto xylose lysine deoxycholate agar. Presumptive Salmonella colonies were biochemically confirmed and analyzed for pathogenicity by hemolysin production and Congo red dye binding assay (CRDA. An antibiotic sensitivity test was performed to assess the antibiotic resistance pattern of the isolates. Results: A total of 10 isolates of Salmonella spp. from meat (3 from cattle, 1 from buffaloes and 6 from pigs with an overall prevalence of 5% among food animals was recorded. No isolation was reported from any blood samples. Pathogenicity assays revealed 100% and 80% positivity for CRDA and hemolytic activity, respectively. Antimicrobial sensitivity test showed multi-drug resistance. The overall resistance of 50% was noted for trimethoprim followed by ampicillin (20%. A maximum sensitivity (80% was reported to gentamycin followed by 40% each to ampicillin and trimethoprim, 30% to amikacin and 10% to kanamycin. Conclusion: The presence of multidrug resistant and potentially pathogenic Salmonella spp. in slaughtered food animals in Nagpur region can be a matter of concern for public health.

  16. Effect of sampling and short isolation methodologies on the recovery of human pathogenic Yersinia enterocolitica from pig tonsils.

    Science.gov (United States)

    Van Damme, Inge; Berkvens, Dirk; De Zutter, Lieven

    2012-07-01

    The objective of this study was to determine the effect of sampling (swab samples compared to destructive samples) on isolation rates of human pathogenic Yersinia enterocolitica from pig tonsils. Moreover, the relative efficiency of different rapid, routinely applicable isolation methods was evaluated. Therefore, swab and destructive samples from tonsils of 120 pigs at slaughter were analyzed in parallel using direct plating and different enrichment methods. Salmonella-Shigella-desoxycholate-calcium chloride (SSDC) agar, cefsulodin-irgasan-novobiocin (CIN) agar, and Yersinia enterocolitica chromogenic medium (YeCM) were used as selective agar media. For enrichment, irgasan-ticarcillin-potassium chlorate (ITC) broth and peptone-sorbitol-bile (PSB) broth were incubated at 25°C for 48 h. Overall, 55 tonsils (45.8%) were positive for Y. enterocolitica bioserotype 4/O:3. Recovery was significantly higher using the destructive method compared to the swabbing method. Direct plating resulted in 47 and 28 Y. enterocolitica-positive destructive and swab samples, respectively. Alkali treatment of PSB and ITC enrichment broths significantly increased recovery of pathogenic Y. enterocolitica from destructive tonsil samples. The performance of YeCM for qualitative and quantitative isolation of pathogenic Y. enterocolitica from pig tonsils was equal to SSDC and CIN. In conclusion, direct plating and ISO 10273: 2003 with minor modifications are suitable and rapid methods for isolation of pathogenic Y. enterocolitica from destructive tonsil samples.

  17. Isolations from the redbay ambrosia beetle, Xyleborus glabratus, confirm that the laurel wilt pathogen, Raffaelea lauricola, originated in Asia

    Science.gov (United States)

    Thomas C. Harrington; Hye Young Yun; Sheng-Shan Lu; Hideaki Goto; Dilzara N. Aghayeva; Stephen W. Fraedrich

    2011-01-01

    The laurel wilt pathogen Raffaelea lauricola was hypothesized to have been introduced to the southeastern USA in the mycangium of the redbay ambrosia beetle, Xyleborus glabratus, which is native to Asia. To test this hypothesis adult X. glabratus were trapped in Taiwan and on Kyushu Island, Japan, in 2009, and dead beetles were sent to USA for isolation of fungal...

  18. Isolation and Characterization of Methyl Parathion-degrading Bacteria Based on Microbial Sensor Construction

    Directory of Open Access Journals (Sweden)

    GENG Fang-fang

    2014-12-01

    Full Text Available Methyl parathion (MP, a kind of typical organophosphates pesticides (OPs, is widely used as agricultural insecticides. However, due to their neurotoxic effects on humans, the elimination of OPs has become increasingly important. Microbial sensors are consisted of biological components and transducers. Owing to their attractive advantages including low cost, easy of miniaturization and excellent selectivity, they have been widely used for environmental analysis. In this paper, four novel bacterial strains capable of utilizing methyl parathion as the sole carbon source were isolated from pesticide contaminated soils. These four isolates were identified based on morphological characteristics and 16S rRNA gene sequences analysis, and their capability of degrading methyl parathion were investigated by high performance liquid chromatography. The highest degrading efficiency strain was selected for further study of degrading mechanism. The results indicated that degradation rate of these four strains were all over 78% after incubation at 30 ℃, pH 7.0 for 7 d with the original concentration of methyl parathion 50 mg·L-1. The highest degradation rate was up to 100%. 16S rRNA gene sequences indicated that strain MP-6 was affiliated into the genus klebsiella. The LC-MS results indicated that methyl parathion was hydrolyzed to dimethyl thiophosphoric acid and p-nitrophenol by MP-6. A little of p-nitrophenol molecules could be further metabolized to 4-nitrocatechol and 1, 2, 4-benzenetrio. The results indicated that based on detecting the potential signal of intermediate product p-nitrophenol, the strain MP-6 could be used to construct microbial sensors for determination of organophosphorus pesticides in environment.

  19. Pathogenicity of Metarrhizium anisopliae (Metsch.) Sorokin and Beauveria bassiana (Bals.) Vuillemin isolates to Scaptocoris carvalhoi Becker (Hemiptera, Cydnidae); Patogenicidade de isolados de Metarhizium anisopliae (Metsch.) Sorokin e de Beauveria bassiana (Bals.) Vuillemin a Scaptocoris carvalhoi Becker (Hemiptera, Cydnidae)

    Energy Technology Data Exchange (ETDEWEB)

    Xavier, Luciane Modenez Saldivar [Universidade Federal da Grande Dourados (UFGD), Dourados, MS (Brazil)], e-mail: luciane_modenez@ibest.com.br; Avila, Crebio Jose [EMBRAPA Agropecuaria Oeste, Dourados, MS (Brazil)], e-mail: crebio@cpao.embrapa.br

    2006-12-15

    Pathogenicity of the fungi Metarrhizium anisopliae (Metsch.) Sorokin and Beauveria bassiana (Bals.) Vuillemin to stink bug Scaptocoris carvalhoi Becker, 1967 was evaluated under laboratory and greenhouse conditions. Experiments were carried out at EMBRAPA Agropecuaria Oeste, Dourados, Mato Grosso do Sul State, Brazil, in 2003. Ten M. anisopliae and eleven B. bassiana isolates were evaluated in laboratory using a completely randomized experimental design with five replicates (10 adults and 5 nymphs/plot). The pathogenicity of M. anisopliae isolate (Ma69) was also separately evaluated against nymphs and adults in laboratory and greenhouse. The stink bug mortality levels were higher for M. anisopliae isolates (between 73.3% and 94.7% than for B. bassiana isolates (between 10.7% and 78.7%). In greenhouse, stink bug mortality due to the M. anisopliae isolate (Ma69) was 57.3%, and there was no difference of mortality for nymphs and adults of stink bug in laboratory. However, in greenhouse, mortality levels were significantly higher (p<0,05) for nymphs (38,4%) than for adults (16,2%). From these data, we conclude that M. anisopliae isolate Ma69 was efficient to control S. carvalhoi in laboratory and in greenhouse, thus being a promising choice for use as a microbial insecticide under field conditions. (author)

  20. Antimicrobial Activity of Carbon Nanoparticles Isolated from Natural Sources against Pathogenic Gram-Negative and Gram-Positive Bacteria

    International Nuclear Information System (INIS)

    Varghese, S.; Jose, S.; Varghese, S.; Kuriakose, S.; Jose, S.

    2013-01-01

    This paper describes the isolation of carbon nanoparticles (CNPs) from kitchen soot, characterization of the CNPs by UV/visible spectroscopy, SEM and XRD, and their antimicrobial action. The antibacterial activity of the isolated carbon nanoparticles was tested against various pathogenic bacterial strains such as Gram-negative Proteus refrigere and Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus and Streptococcus haemolyticus. The inhibition zones were measured, and it was found that the carbon nanoparticles isolated from natural sources are active against these Gram-negative and Gram-positive bacterial strains

  1. Occurrence of weak mutators among avian pathogenic Escherichia coli (APEC) isolates causing salpingitis and peritonitis in broiler breeders

    DEFF Research Database (Denmark)

    Pires dos Santos, Teresa M S; Bisgaard, Magne; Kyvsgaard, Niels Christian

    2014-01-01

    A collection of 46 avian pathogenic Escherichia coli (APEC) isolates was examined for the presence of mutators by determining the rate of mutation to rifampicin resistance. The collection included 34 E. coli isolates obtained in pure culture from chronic lesions of salpingitis and peritonitis in 34...... broiler breeders, of which 12 were associated with the development of secondary septicemia. Twelve additional isolates were obtained from a clonal outbreak (ST95) of E. coli peritonitis syndrome (EPS), the lesions of which changed gradually over time into a subacute/chronic form. The hypothesis...

  2. Bovine mastitis disease/pathogenicity: evidence of the potential role of microbial biofilms.

    Science.gov (United States)

    Gomes, Fernanda; Saavedra, Maria José; Henriques, Mariana

    2016-04-01

    Bovine mastitis (BM) is a disease with high incidence worldwide and one of the most relevant bovine pathologies and the most costly to the dairy industry. BM is an inflammation of the udder and represents one of the most difficult veterinary diseases to control. Biofilm formation is considered a selective advantage for pathogens causing mastitis, facilitating bacterial persistence in the udder. In fact, recently some authors drew attention to the biofilm formation ability presented by several mastitis causing pathogens and to its possible relation with recurrent mastitis infections and with the increased resistance to antimicrobial agents and host immune defence system. Actually, up to now, several researchers reported the potential role of cells in this mode of growth in the previous facts mentioned. As a consequence of the presence of biofilms, the infection here focused is more difficult to treat and eradicate, making this problem a more relevant pressing issue. Thus, we believe that a deeper knowledge of these structures in mastitis can help to determine the best control strategy to be used in veterinary practice in order to reduce losses in the dairy industry and to ensure milk safety and quality. The aim of this paper was to review the existing research and consequently to provide an overview of the role of biofilms in BM infections. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Analysis of a food-borne fungal pathogen outbreak: virulence and genome of a Mucor circinelloides isolate from yogurt.

    Science.gov (United States)

    Lee, Soo Chan; Billmyre, R Blake; Li, Alicia; Carson, Sandra; Sykes, Sean M; Huh, Eun Young; Mieczkowski, Piotr; Ko, Dennis C; Cuomo, Christina A; Heitman, Joseph

    2014-07-08

    Food-borne pathogens are ongoing problems, and new pathogens are emerging. The impact of fungi, however, is largely underestimated. Recently, commercial yogurts contaminated with Mucor circinelloides were sold, and >200 consumers became ill with nausea, vomiting, and diarrhea. Mucoralean fungi cause the fatal fungal infection mucormycosis, whose incidence has been continuously increasing. In this study, we isolated an M. circinelloides strain from a yogurt container, and multilocus sequence typing identified the strain as Mucor circinelloides f. circinelloides. M. circinelloides f. circinelloides is the most virulent M. circinelloides subspecies and is commonly associated with human infections, whereas M. circinelloides f. lusitanicus and M. circinelloides f. griseocyanus are less common causes of infection. Whole-genome analysis of the yogurt isolate confirmed it as being close to the M. circinelloides f. circinelloides subgroup, with a higher percentage of divergence with the M. circinelloides f. lusitanicus subgroup. In mating assays, the yogurt isolate formed sexual zygospores with the (-) M. circinelloides f. circinelloides tester strain, which is congruent with its sex locus encoding SexP, the (+) mating type sex determinant. The yogurt isolate was virulent in murine and wax moth larva host systems. In a murine gastromucormycosis model, Mucor was recovered from fecal samples of infected mice for up to 10 days, indicating that Mucor can survive transit through the GI tract. In interactions with human immune cells, M. circinelloides f. lusitanicus induced proinflammatory cytokines but M. circinelloides f. circinelloides did not, which may explain the different levels of virulence in mammalian hosts. This study demonstrates that M. circinelloides can spoil food products and cause gastrointestinal illness in consumers and may pose a particular risk to immunocompromised patients. Importance: The U.S. FDA reported that yogurt products were contaminated with M

  4. Identification of Two Pathogenic Aeromonas Species Isolated during Production Related Epizootics from Juvenile Burbot Lota lota maculosa.

    Science.gov (United States)

    Terrazas, Marc M; Anderson, Cort L; Jacobs, Sarah J; Cain, Kenneth D

    2018-05-25

    In response to population declines of Burbot Lota lota maculosa, conservation aquaculture methods have been developed for this species. In general, Burbot are relatively resistant to many salmonid pathogens; however, cultured juvenile Burbot have experienced periodic epizootic disease outbreaks during production. A series of trials were conducted to determine the virulence of select bacteria isolated from juvenile Burbot following outbreaks that occurred in 2012 and 2013 at the University of Idaho's Aquaculture Research Institute. Initial clinical diagnostics and sampling resulted in the isolation of numerous putative bacterial pathogens. To determine which bacteria were the most likely causative agents contributing to these epizootics, juvenile Burbot were injectied intraperitoneally (IP) with select bacteria in log phase growth. Mortality associated with specific isolates was recorded, and more comprehensive challenges followed this initial screening. These challenges used side-by-side IP and immersion methods to expose Burbot to potential pathogens. The challenges resulted in significantly higher mortalities in fish following IP injection of two Aeromonas sp. isolates compared to controls (P ≤ 0.01), but no difference in mortality for immersion challenged groups was observed (P = 0.42). Results demonstrate that two isolates (Aeromonas sp.) cultured from the epizootics are virulent to Burbot. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. Identification of a microsporidian isolate from Cnaphalocrocis Medinalis and its pathogenicity to Bombyx mori.

    Science.gov (United States)

    Huang, Xuhua; Qi, Guangjun; Pan, Zhixin; Zhu, Fangrong; Huang, Yuanjiao; Wu, Yonghu

    2014-11-01

    A microsporidian, CmM2, was isolated from Cnaphalocrocis medinalis. The biological characters, molecular analysis and pathogenicity of CmM2 were studied. The spore of CmM2 is long oval in shape and 3.45 ± 0.25 × 1.68 ± 0.18 µm in size, the life cycle includes meronts, sporonts, sporoblasts, and spores, with typical diplokaryon in each stage, propagated in binary fission. There is positive coagulation reaction between CmM2 and the polyclonal antibody of Nosema bombycis (N.b.). CmM2 spores is binuclear, and has 10-12 polar filament coils. The small subunit ribosomal RNA (SSU rRNA) gene sequence of CmM2 was obtained by PCR amplification and sequencing, the phylogenetic tree based on SSU rRNA sequences had been constructed, and the similarity and genetic distance of SSU rRNA sequences were analyzed, showed that CmM2 was grouped in the Nosema clade. The 50% infectious concentration of CmM2 to Bombyx mori is 4.72 × 10(4)  spores ml(-1) , and the germinative infection rate is 12.33%. The results showed that CmM2 is classified into genus Nosema, as Nosema sp. CmM2, and has a heavy infectivity to B. mori. The result indicated as well that it is valuable taxonomic determination for microsporidian isolates based on both biological characters and molecular evidence. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Isolation and Probiotic Potential of Lactobacillus Salivarius and Pediococcus Pentosaceus in Specific Pathogen Free Chickens

    Directory of Open Access Journals (Sweden)

    F Chen

    Full Text Available ABSTRACT This study was conducted to isolate Lactobacillus salivarius and Pediococcus pentosaceus strains from cecal content and investigate their probiotic potential in specific pathogen free (SPF chickens. L. salivarius and P. pentosaceus strains were isolated from the cecal content of SPF chickens and identified by 16s rDNA sequence analysis by BLAST analysis at the National Center for Biotechnology Information and phylogenetic analysis using DNAStar software. In an in vivo experiment, 180 7-day-old SPF chickens were randomly assigned into three groups. Group 1 served as a control that was fed a basal diet without probiotic supplementation, and groups 2 and 3 were fed the basal diets supplemented with L. salivarius and P. pentosaceus at 2×108 CFU/g, respectively. Body weight (BW, average daily gain (ADG, feed conversion ratio (FCR, dressing percentage (DP, and the apparent digestibility of crude protein (AD-CP were calculated. We also determined meat color, fat content, shear force, water content and pH value of breast and thigh muscles; ammonia, urea nitrogen and uric acid content in plasma; fecal ammonia emission level and pH value; and Lactobacillus and Escherichia coli in ceca. Compared with the control group, L. salivarius and P. pentosaceus supplementation significantly increased BW, ADG, DP, AD-CP, fat content of meat, and the number of Lactobacillus in ceca (p<0.05, and decreased FCR, plasma ammonia content, fecal ammonia emission, and pH value and the number of E. coli in ceca (p<0.05. In the in vitro experiment, L. salivarius and P. pentosaceus treatments significantly decreased the ammonia content in medium compared with the control group without probiotic treatment (p<0.05. These results suggest that P. pentosaceus and L. salivarius strains show promising probiotic properties for improving growth, meat quality and microenvironment in chickens and decreasing ammonia content in the medium.

  7. Relationships among superantigen toxin gene profiles, genotypes, and pathogenic characteristics of Staphylococcus aureus isolates from bovine mastitis.

    Science.gov (United States)

    Wang, Dong; Zhang, Limei; Yong, Changfu; Shen, Mingliang; Ali, Tariq; Shahid, Muhammad; Han, Kun; Zhou, Xuezhang; Han, Bo

    2017-06-01

    Staphylococcus aureus is one of the major etiological agents of bovine mastitis, harboring a wide variety of staphylococcal superantigen (SAg) toxin genes. The SAg toxin genes are reported to be closely associated with the pathogenicity of the Staph. aureus causing the bovine mastitis. This study was conducted to investigate SAg toxin gene profiles and to assess the relationships among SAg toxin genes, genotypes of Staph. aureus, and their pathogenic properties. A total of 327 quarter milk samples were collected from bovine mastitis cases for isolation and identification of pathogens. In total, 35 isolates were identified as Staph. aureus, and the prevalence of Staph. aureus in milk samples was 13.6% (35/256). Polymerase chain reaction (PCR) and randomly amplified polymorphic DNA (RAPD) assays were used to detect the SAg toxin genes and to genotype Staph. aureus strains isolated from milk samples of bovine mastitis in 10 dairy herds located in Ningxia, China, respectively. The results showed that among the Staph. aureus isolates (n = 35), 71.4% (n = 25) of isolates carried at least one SAg toxin gene. In total, 18 SAg genes and 21 different gene combination patterns were detected among these isolates. The most common SAg genes in Staph. aureus isolates were sei, sen, and seu (44.0% each), followed by seo, tst, and etB (28.0% each), etA (24.0%), sem and sep (16.0% each), seb, sec, sed, and sek (12.0% each), and sea and seh genes (8.0% each); the seg, sej, and ser genes were present in 4.0% of the isolates. Three gene combinations were found to be related to mobile genetic elements that carried 2 or more genes. The egc-cluster of the seg-sei-sem-sen-seo genes, located on the pathogenicity island Type I υSaβ, was detected in 16% of isolates. Interestingly, we observed 6 RAPD genotypes (I to VI) in Staph. aureus isolates, and 2 of these genotypes were strongly associated with the severity of bovine mastitis; there was a close relationship between the RAPD genotypes

  8. The causes and consequences of antibiotic resistance evolution in microbial pathogens

    DEFF Research Database (Denmark)

    Jochumsen, Nicholas

    pleiotropy as they conferred a decreased growth rate in the absence of colistin and also rendered the colistin resistant strains susceptible towards all tested classes of β-lactams. The results suggest that colistin/β-lactam combination therapy could be used to reduce the risk of resistance evolution during......The evolution of antimicrobial resistance in bacterial pathogens is a growing global health problem that is gradually making the successful treatment of infectious diseases more difficult. Antimicrobial peptides have been proposed as promising candidates for future drug development as they retain...... activity against bacteria resistant to conventional antibiotics and because resistance evolution is expected to be unlikely since the peptides have complex modes of action due to their interaction with the bacterial membrane. The work presented in this thesis has involved studies to increase our...

  9. Mechanistic investigation on microbial toxicity of nano hydroxyapatite on implant associated pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Baskar, K. [Department of Biotechnology, University of Madras, Guindy Campus, Chennai, Tamil Nadu (India); Anusuya, T. [Department of Nanotechnology, SRM University, Kattankulathur, Tamil Nadu (India); Devanand Venkatasubbu, G., E-mail: gdevanandvenkatasubbu@gmail.com [Department of Nanotechnology, SRM University, Kattankulathur, Tamil Nadu (India)

    2017-04-01

    The use of atomic scale inorganic nanoparticles (NPs) to fight against pathogenic microorganisms is a recent trend in biomedical area which overcomes the limitations of organic compounds in terms of stability, shelf life and bioactivity. One such Calcium phosphate based biomaterial is hydroxyapatite (HA), considered as potential bioactive compound with excellent biocompatibility, osteointegrity and biodegradability. Osteomyelitis, the implant associated infection, is the major problem worldwide responsible for the majority of implant failure cases. Since HA is used as a coating material of implants, only few reports were available on its antimicrobial activity and cytotoxicity whereas no reports on its possible antimicrobial mechanism. In this present study, the HA-NPs were synthesized by wet chemical precipitation and were characterized using X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The synthesized HA-NPs were evaluated for antimicrobial activity against implant associated bacterial pathogens. The study also explores the mechanistic action of HA-NPs in killing of bacteria by determining the reactive oxygen species (ROS) generation, DNA fragmentation, Lactate dehydrogenase (LDH) leakage and cellular interaction. In addition the cytotoxicity of HA-NPs was determined by MTT assay and Fluorescence Microscopic analysis. The results revealed that, the synthesized HA-NPs showed good antibacterial activity for tested bacterial species and the possible antibacterial mechanism were due to the lack of membrane integrity and cytotoxic studies shows the concentration dependent changes in cell viability. - Highlights: • Antibacterial activity against Gram − ve bacterium • Mechanism of antibacterial activity is analyzed. • DNA fragmentation, growth curve, LDH, ROS are analyzed. • The mechanism is by damaging cell membrane. • Hydroxyapatite is biocompatible.

  10. Plant Pathogenic Microbial Communication Affected by Elevated Temperature in Pectobacterium carotovorum subsp. carotovorum.

    Science.gov (United States)

    Saha, N D; Chaudhary, A; Singh, S D; Singh, D; Walia, S; Das, T K

    2015-11-01

    Gram-negative plant pathogenic bacteria regulate specific gene expression in a population density-dependent manner by sensing level of Acyl-Homoserine Lactone (HSL) molecules which they produce and liberate to the environment, called Quorum Sensing (QS). The production of virulence factors (extracellular enzyme viz. cellulase, pectinase, etc.) in Pectobacterium carotovorum subsp. carotovorum (Pcc) is under strong regulation of QS. The QS signal molecule, N-(3-oxohexanoyl)-L-Homoserine Lactone (OHHL) was found as the central regulatory system for the virulence factor production in Pcc and is also under strict regulation of external environmental temperature. Under seven different incubation temperatures (24, 26, 28, 30, 33, 35, and 37 °C) in laboratory condition, highest amount of OHHL (804 violacein unit) and highest (79 %) Disease Severity Index (DSI) were measured at 33 °C. The OHHL production kinetics showed accumulation of highest concentration of OHHL at late log phase of the growth but diminution in the concentration occurred during stationary phase onwards to death phase. At higher temperature (35 and 37 °C) exposure, OHHL was not at detectable range. The effect of temperature on virulence factor production is the concomitant effect of HSL production and degradation which justifies less disease severity index in cross-inoculated tomato fruits incubated at 35 and 37 °C. The nondetection of the OHHL in the elevated temperature may because of degradation as these signal molecules are quite sensitive and prone to get degraded under different physical factors. This result provides the rationale behind the highest disease severity up to certain elevated temperature and leaves opportunities for investigation on mutation, co-evolution of superior plant pathogen with more stable HSL signals-mediated pathogenesis under global warming context.

  11. Zinc bioaccumulation by microbial consortium isolated from nickel smelter sludge disposal site

    Directory of Open Access Journals (Sweden)

    Kvasnová Simona

    2017-06-01

    Full Text Available Heavy metal pollution is one of the most important environmental issues of today. Bioremediation by microorganisms is one of technologies extensively used for pollution treatment. In this study, we investigated the heavy metal resistance and zinc bioaccumulation by microbial consortium isolated from nickel sludge disposal site near Sereď (Slovakia. The composition of consortium was analyzed based on MALDI-TOF MS of cultivable bacteria and we have shown that the consortium was dominated by bacteria of genus Arthrobacter. While consortium showed very good growth in the zinc presence, it was able to remove only 15 % of zinc from liquid media. Selected members of consortia have shown lower growth rates in the zinc presence but selected isolates have shown much higher bioaccumulation abilities compared to whole consortium (up to 90 % of zinc removal for NH1 strain. Bioremediation is frequently accelerated through injection of native microbiota into a contaminated area. Based on data obtained in this study, we can conclude that careful selection of native microbiota could lead to the identification of bacteria with increased bioaccumulation abilities.

  12. Isolation and expression of recombinant antibody fragments to the biological warfare pathogen Brucella melitensis.

    Science.gov (United States)

    Hayhurst, Andrew; Happe, Scott; Mabry, Robert; Koch, Zephyr; Iverson, Brent L; Georgiou, George

    2003-05-01

    Brucella melitensis is a highly infectious animal pathogen able to cause a recurring debilitating disease in humans and is therefore high on the list of biological warfare agents. Immunoglobulin genes from mice immunized with gamma-irradiated B. melitensis strain 16M were used to construct a library that was screened by phage display against similarly prepared bacteria. The selected phage particles afforded a strong enzyme-linked immunosorbent assay (ELISA) signal against gamma-irradiated B. melitensis cells. However, extensive efforts to express the respective single chain antibody variable region fragment (scFv) in soluble form failed due to: (i) poor solubility and (ii) in vivo degradation of the c-myc tag used for the detection of the recombinant antibodies. Both problems could be addressed by: (i) fusing a human kappa light chain constant domain (Ck) chain to the scFv to generate single chain antibody fragment (scAb) antibody fragments and (ii) by co-expression of the periplasmic chaperone Skp. While soluble, functional antibodies could be produced in this manner, phage-displaying scFvs or scAbs were still found to be superior ELISA reagents for immunoassays, due to the large signal amplification afforded by anti-phage antibodies. The isolated phage antibodies were shown to be highly specific to B. melitensis and did not recognize Yersinia pseudotuberculosis in contrast to the existing diagnostic monoclonal YST 9.2.1.

  13. Antimicrobial property of lemongrass (Cymbopogon citratus) oil against pathogenic bacteria isolated from pet turtles.

    Science.gov (United States)

    De Silva, B C J; Jung, Won-Gi; Hossain, Sabrina; Wimalasena, S H M P; Pathirana, H N K S; Heo, Gang-Joon

    2017-06-01

    The usage of essential oils as antimicrobial agents is gaining attention. Besides, pet turtles were known to harbor a range of pathogenic bacteria while the turtle keeping is a growing trend worldwide.The current study examined the antimicrobial activity of lemon grass oil (LGO) against seven species of Gram negative bacteria namely; Aeromonas hydrophila , A. caviae , Citrobacter freundii , Salmonella enterica , Edwardsiella tarda , Pseudomonas aeruginosa , and Proteus mirabilis isolated from three popular species of pet turtles. Along with the results of disc diffusion, minimum inhibitory and minimum bactericidal concentration (MIC and MBC) tests, LGO was detected as effective against 6 species of bacteria excluding P. aeruginosa . MIC of LGO for the strains except P. aeruginosa ranged from 0.016 to 0.5% (V/V). The lowest MIC recorded in the E. tarda strain followed by A. hydrophilla , C. freundii , P. mirabilis , and S. enterica . Interestingly, all the bacterial species except E. tarda were showing high multiple antimicrobial resistance (MAR) index values ranging from 0.36 to 0.91 upon the 11 antibiotics tested although they were sensitive to LGO.

  14. Mass spectrometry-based bacterial proteomics: focus on dermatological associated microbial pathogens

    Directory of Open Access Journals (Sweden)

    Youcef eSoufi

    2016-02-01

    Full Text Available The composition of human skin acts as a natural habitat for various bacterial species that function in a commensal and symbiotic fashion. In a healthy individual, bacterial flora serves to protect the host. Under certain conditions such as minor trauma, impaired host immunity, or environmental factors, the risk of developing skin infections is increased. Although a large majority of bacterial associated skin infections are common, a portion can potentially manifest into clinically significant morbidity. For example, Gram positive species that typically reside on the skin such as Staphylococcus and Streptococcus can cause numerous epidermal (impetigo, ecthyma and dermal (cellulitis, necrotizing fasciitis, erysipelas skin infections. Moreover, the increasing incidence of bacterial antibiotic resistance represents a serious challenge to modern medicine and threatens the health care system. Therefore, it is critical to develop tools and strategies that can allow us to better elucidate the nature and mechanism of bacterial virulence. To this end, mass spectrometry (MS-based proteomics has been revolutionizing biomedical research, and has positively impacted the microbiology field. Advances in MS technologies have paved the way for numerous bacterial proteomes and their respective post translational modifications (PTMs to be accurately identified and quantified in a high throughput and robust fashion. This technological platform offers critical information with regards to signal transduction, adherence, and microbial-host interactions associated with bacterial pathogenesis. This mini-review serves to highlight the current progress proteomics has contributed towards the understanding of bacteria that are associated with skin related diseases, infections, and antibiotic resistance.

  15. Development of a standardized differential-reflective bioassay for microbial pathogens

    Science.gov (United States)

    Wilhelm, Jay; Auld, J. R. X.; Smith, James E.

    2008-04-01

    This research examines standardizing a method for the rapid/semi-automated identification of microbial contaminates. It introduces a method suited to test for food/water contamination, serology, urinalysis and saliva testing for any >1 micron sized molecule that can be effectively bound to an identifying marker with exclusivity. This optical biosensor method seeks to integrate the semi-manual distribution of a collected sample onto a "transparent" substrate array of binding sites that will then be applied to a standard optical data disk and run for analysis. The detection of most microbe species is possible in this platform because the relative scale is greater than the resolution of the standard-scale digital information on a standard CD or DVD. This paper explains the critical first stage in the advance of this detection concept. This work has concentrated on developing the necessary software component needed to perform highly sensitive small-scale recognition using the standard optical disk as a detection platform. Physical testing has made significant progress in demonstrating the ability to utilize a standard optical drive for the purposes of micro-scale detection through the exploitation of CIRC error correction. Testing has also shown a definable trend in the optimum scale and geometry of micro-arrayed attachment sites for the technology's concept to reach achievement.

  16. First report of a cross-kingdom pathogenic bacterium, Achromobacter xylosoxidans isolated from stipe-rot Coprinus comatus.

    Science.gov (United States)

    Ye, Luona; Guo, Mengpei; Ren, Pengfei; Wang, Gangzheng; Bian, Yinbing; Xiao, Yang; Zhou, Yan

    2018-03-01

    Coprinus comatus is an edible mushroom widely cultivated in China as a delicious food. Various diseases have occurred on C. comatus with the cultivated area increasing. In this study, the pathogenic bacterium JTG-B1, identified as Achromobacter xylosoxidans by 16S rDNA and nrdA gene sequencing, was isolated from edible mushroom Coprinus comatus with serious rot disease on its stipe. A. xylosoxidans has been confirmed as an important opportunistic human pathogenic bacterium and has been isolated from respiratory samples from cystic fibrosis. It is widely distributed in the environment. Here, we first report that fungi can also serve as a host for A. xylosoxidans. We confirmed that it can cross-kingdom infect between animals (mice) and fungi (C. comatus). The results of pathogenicity tests, physiological, biochemical and genotyping analysis of A. xylosoxidans from different hosts suggested that different strain of A. xylosoxidans may have pathogenicity differentiation. A. xylosoxidans not only is pathogenic to C. comatus but also may threaten human health. Copyright © 2017 Elsevier GmbH. All rights reserved.

  17. Microbial contamination of red meat and consideration of gamma irradiation effects for increasing the shelf-life and decontamination of pathogenic microorganisms

    International Nuclear Information System (INIS)

    Motamedee Sadeh, F.; Majd, F.; Fathollahee, H.; Arbabi, K.; Mohammad Beygi Abhari, M.

    2003-01-01

    Red meat has a lot of microbial flora from different sources. Prevention of outbreak of food born diseases that are caused by pathogenic agents and prevention of microbial spoilage of meat that makes many losses to the human health and economic of society are very important. Also, different methods for decreasing the microbial flora under a standard allowance for increasing the shelf life and decontamination of microbial pathogens have been proposed. In this research, irradiation technique was used for this purposes. After drawing dose/survival curves for all kinds of meats microbial contamination, an optimum dose of 3 kGy for decreasing the contamination and specially for decontamination of salmonella was obtained. When meat is irradiated by 3 kGy gamma rays, it can be kept in a 4-7 d ig C refrigerator for 2 week without appearing any spoilage nor color changes or odor. Also, some of biochemical factors were analyzed and amounts of 16 amino acids were measured in the irradiated and controlled samples and no difference was observed between the samples

  18. How often do they have sex? A comparative analysis of the population structure of seven eukaryotic microbial pathogens.

    Directory of Open Access Journals (Sweden)

    Nicolás Tomasini

    Full Text Available The model of predominant clonal evolution (PCE proposed for micropathogens does not state that genetic exchange is totally absent, but rather, that it is too rare to break the prevalent PCE pattern. However, the actual impact of this "residual" genetic exchange should be evaluated. Multilocus Sequence Typing (MLST is an excellent tool to explore the problem. Here, we compared online available MLST datasets for seven eukaryotic microbial pathogens: Trypanosoma cruzi, the Fusarium solani complex, Aspergillus fumigatus, Blastocystis subtype 3, the Leishmania donovani complex, Candida albicans and Candida glabrata. We first analyzed phylogenetic relationships among genotypes within each dataset. Then, we examined different measures of branch support and incongruence among loci as signs of genetic structure and levels of past recombination. The analyses allow us to identify three types of genetic structure. The first was characterized by trees with well-supported branches and low levels of incongruence suggesting well-structured populations and PCE. This was the case for the T. cruzi and F. solani datasets. The second genetic structure, represented by Blastocystis spp., A. fumigatus and the L. donovani complex datasets, showed trees with weakly-supported branches but low levels of incongruence among loci, whereby genetic structuration was not clearly defined by MLST. Finally, trees showing weakly-supported branches and high levels of incongruence among loci were observed for Candida species, suggesting that genetic exchange has a higher evolutionary impact in these mainly clonal yeast species. Furthermore, simulations showed that MLST may fail to show right clustering in population datasets even in the absence of genetic exchange. In conclusion, these results make it possible to infer variable impacts of genetic exchange in populations of predominantly clonal micro-pathogens. Moreover, our results reveal different problems of MLST to determine the

  19. Analysis of clinical isolates of Helicobacter pylori in Pakistan reveals high degrees of pathogenicity and high frequencies of antibiotic resistance.

    Science.gov (United States)

    Rasheed, Faisal; Campbell, Barry James; Alfizah, Hanafiah; Varro, Andrea; Zahra, Rabaab; Yamaoka, Yoshio; Pritchard, David Mark

    2014-10-01

    Antibiotic resistance in Helicobacter pylori contributes to failure in eradicating the infection and is most often due to point and missense mutations in a few key genes. The antibiotic susceptibility profiles of H. pylori isolates from 46 Pakistani patients were determined by Etest. Resistance and pathogenicity genes were amplified, and sequences were analyzed to determine the presence of mutations. A high percentage of isolates (73.9%) were resistant to metronidazole (MTZ), with considerable resistance to clarithromycin (CLR; 47.8%) and amoxicillin (AML; 54.3%) also observed. Relatively few isolates were resistant to tetracycline (TET; 4.3%) or to ciprofloxacin (CIP; 13%). However, most isolates (n = 43) exhibited resistance to one or more antibiotics. MTZ-resistant isolates contained missense mutations in oxygen-independent NADPH nitroreductase (RdxA; 8 mutations found) and NADH flavin oxidoreductase (FrxA; 4 mutations found). In the 23S rRNA gene, responsible for CLR resistance, a new point mutation (A2181G) and 4 previously reported mutations were identified. Pathogenicity genes cagA, dupA, and vacA s1a/m1 were detected frequently in isolates which were also found to be resistant to MTZ, CLR, and AML. A high percentage of CagA and VacA seropositivity was also observed in these patients. Phylogenetic analysis of partial sequences showed uniform distribution of the 3' region of cagA throughout the tree. We have identified H. pylori isolates in Pakistan which harbor pathogenicity genes and worrying antibiotic resistance profiles as a result of having acquired multiple point and missense mutations. H. pylori eradication regimens should therefore be reevaluated in this setting. © 2014 John Wiley & Sons Ltd.

  20. Pathogenicity and molecular detection of Uruguayan isolates of Greeneria uvicola and Cadophora luteo-olivacea associated with grapevine trunk diseases

    Directory of Open Access Journals (Sweden)

    Fernando NAVARRETE

    2011-12-01

    Full Text Available Normal 0 21 MicrosoftInternetExplorer4 Species from different fungal genera have been indicated as responsible for the development of trunk diseases of grapevines. Greeneria uvicola is responsible for the bitter rot of Vitis vinifera grape bunchesnear harvest, and can also attack other Vitis species. In Uruguay, G. uvicola was isolated from dead arm affected grapevines and as an endophyte from healthy canes. Cadophora luteo-olivacea is a phialophora-likeascomycete with a wide distribution that was isolated from asymptomatic wood tissues in Vitis and Petridisease-affected nursery plants in Uruguay. Pathogenicity of isolates of both species was evaluated on Vitis vinifera cv. Tannat and Cabernet Sauvignon, and rootstocks SO4 and 3309C. Specific primers were developed for the ITS rDNA region for both species. Number of plants showing discoloration, length of discoloration, number of re-isolations and amplifications confirmed the pathogenicity of G. uvicola isolates. Pathogenicityof the isolate of C. luteo-olivacea obtained from symptomatic tissues is discussed. Specific primers can be usedto detect the presence of these fungi in asymptomatic tissues.

  1. RAPD cluster analysis and chlorate sensitivity of some Indian isolates of Macrophomina phaseolina from sorghum and their relationships with pathogenicity.

    Science.gov (United States)

    Das, I K; Fakrudin, B; Arora, D K

    2008-01-01

    Charcoal rot caused by Macrophomina phaseolina is an economically important disease in sorghum grown during the post rainy season in India. Variations in random amplified polymorphic DNA (RAPD) polymorphisms, chlorate sensitivity and pathogenicity were studied among sorghum isolates of M. phaseolina collected from different parts of India. RAPD data based on 14 random primers of Kit A and C (OPA and OPC) on 20 isolates showed a high degree of polymorphism (98.1%) in different isolates. UPGMA dendrogram on RAPD data produced 7 clusters at the level of 37% similarity. Isolates from the same locations showed a tendency to group closer, substantiating closer genetic relatedness. Sorghum infecting Macrophomina isolates showed a mixed response for sensitivity to potassium chlorate (120 mM). Chlorate-resistant isolates were predominant (>65% of the isolates) over sensitive isolates. Chlorate-sensitive isolates were found to be genetically closer among them than the resistant ones. For the first time it was shown that chlorate sensitivity in Macrophomina had some relations with charcoal rot severity in sorghum.

  2. UV-Heat Treatments for the Control of Foodborne Microbial Pathogens in Chicken Broth

    Directory of Open Access Journals (Sweden)

    M. Gouma

    2015-01-01

    Full Text Available This investigation established the process criteria for using UV-C light and mild heat (UV-H treatment to inactivate 5-Log10 cycles (performance criterion of common foodborne pathogen populations, Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, and Staphylococcus aureus, when inoculated in chicken broth. To define the target microorganism and the proper UV-H treatment conditions (including UV dose, treatment time, and temperature that would achieve the stated performance criterion, mathematical equations based on Geeraerd’s model were developed for each microorganism. For the sake of comparison, inactivation equations for heat treatments were also performed on the same chicken broth and for the same microorganisms. L. monocytogenes was the most UV-H resistant microorganism at all temperatures, requiring a UV dose between 6.10 J/mL (5.6 min and 2.26 J/mL (2.09 min to achieve 5-Log10 reductions. In comparison with UV treatments at room temperatures, the combination of UV and mild heat allowed both the UV dose and treatment time to be reduced by 30% and 63% at 55°C and 60°C, respectively. Compared to heat treatments, the UV-H process reduced the heating time for 5-Log10 reductions of all the investigated microorganisms in chicken broth from 20-fold to 2-fold when the operating temperature varied from 53 to 60°C.

  3. Contagem de células somáticas e isolamento de agentes causadores de mastite em búfalas (Bubalus bubalis Somatic cell count and mastitis causing pathogens isolation in water buffaloes (Bubalus bubalis

    Directory of Open Access Journals (Sweden)

    L.B. Carvalho

    2007-02-01

    Full Text Available The research was accomplished in eight dairy water buffalo herds, randomically choosen in Região do Alto São Francisco, State of Minas Gerais, Brazil. Information was collected from March to November, 2003 during 270 days of observation. In order to determine the somatic cell count (SCC in presence or absence of microbial isolation, 1,393 samples were collected from 285 lactating females and microbiological exams and SCC were done. Samples obtained from udders without evidence of clinical or subclinical inflammation showed infection for a great variety of microbial mastitis pathogens. The low SCC did not necessarily indicate the absence of intramammary infection, suggesting that SCC patterns used for bovine cannot be appropriate in order to control mastitis in buffalo herds.

  4. Conserved Patterns of Microbial Immune Escape: Pathogenic Microbes of Diverse Origin Target the Human Terminal Complement Inhibitor Vitronectin via a Single Common Motif.

    Directory of Open Access Journals (Sweden)

    Teresia Hallström

    Full Text Available Pathogenicity of many microbes relies on their capacity to resist innate immunity, and to survive and persist in an immunocompetent human host microbes have developed highly efficient and sophisticated complement evasion strategies. Here we show that different human pathogens including Gram-negative and Gram-positive bacteria, as well as the fungal pathogen Candida albicans, acquire the human terminal complement regulator vitronectin to their surface. By using truncated vitronectin fragments we found that all analyzed microbial pathogens (n = 13 bound human vitronectin via the same C-terminal heparin-binding domain (amino acids 352-374. This specific interaction leaves the terminal complement complex (TCC regulatory region of vitronectin accessible, allowing inhibition of C5b-7 membrane insertion and C9 polymerization. Vitronectin complexed with the various microbes and corresponding proteins was thus functionally active and inhibited complement-mediated C5b-9 deposition. Taken together, diverse microbial pathogens expressing different structurally unrelated vitronectin-binding molecules interact with host vitronectin via the same conserved region to allow versatile control of the host innate immune response.

  5. Antigenic, genetic, and pathogenic characterization of H5N1 highly pathogenic avian influenza viruses isolated from dead whooper swans (Cygnus cygnus) found in northern Japan in 2008.

    Science.gov (United States)

    Okamatsu, Masatoshi; Tanaka, Tomohisa; Yamamoto, Naoki; Sakoda, Yoshihiro; Sasaki, Takashi; Tsuda, Yoshimi; Isoda, Norikazu; Kokumai, Norihide; Takada, Ayato; Umemura, Takashi; Kida, Hiroshi

    2010-12-01

    In April and May 2008, whooper swans (Cygnus cygnus) were found dead in Hokkaido in Japan. In this study, an adult whooper swan found dead beside Lake Saroma was pathologically examined and the identified H5N1 influenza virus isolates were genetically and antigenically analyzed. Pathological findings indicate that the swan died of severe congestive edema in the lungs. Phylogenetic analysis of the HA genes of the isolates revealed that they are the progeny viruses of isolates from poultry and wild birds in China, Russia, Korea, and Hong Kong. Antigenic analyses indicated that the viruses are distinguished from the H5N1 viruses isolated from wild birds and poultry before 2007. The chickens vaccinated with A/duck/Hokkaido/Vac-1/2004 (H5N1) survived for 14 days after challenge with A/whooper swan/Hokkaido/1/2008 (H5N1), although a small amount of the challenge virus was recovered from the tissues of the birds. These findings indicate that H5N1 highly pathogenic avian influenza viruses are circulating in wild birds in addition to domestic poultry in Asia and exhibit antigenic variation that may be due to vaccination.

  6. Antibacterial Activity of Pharbitin, Isolated from the Seeds of Pharbitis nil, against Various Plant Pathogenic Bacteria.

    Science.gov (United States)

    Nguyen, Hoa Thi; Yu, Nan Hee; Park, Ae Ran; Park, Hae Woong; Kim, In Seon; Kim, Jin-Cheol

    2017-10-28

    This study aimed to isolate and characterize antibacterial metabolites from Pharbitis nil seeds and investigate their antibacterial activity against various plant pathogenic bacteria. The methanol extract of P. nil seeds showed the strongest activity against Xanthomonas arboricola pv. pruni (Xap) with a minimum inhibition concentration (MIC) value of 250 μg/ml. Among the three solvent layers obtained from the methanol extract of P. nil seeds, only the butanol layer displayed the activity with an MIC value of 125 μg/ml against Xap. An antibacterial fraction was obtained from P. nil seeds by repeated column chromatography and identified as pharbitin, a crude resin glycoside, by instrumental analysis. The antibacterial activity of pharbitin was tested in vitro against 14 phytopathogenic bacteria, and it was found to inhibit Ralstonia solanacearum and four Xanthomonas species. The minimum inhibitory concentration values against the five bacteria were 125-500 μg/ml for the n-butanol layer and 31.25-125 μg/ml for pharbitin. In a detached peach leaf assay, it effectively suppressed the development of bacterial leaf spot, with a control value of 87.5% at 500 μg/ml. In addition, pharbitin strongly reduced the development of bacterial wilt on tomato seedlings by 97.4% at 250 μg/ml, 7 days after inoculation. These findings suggest that the crude extract of P. nil seeds can be used as an alternative biopesticide for the control of plant diseases caused by R. solanacearum and Xanthomonas spp. This is the first report on the antibacterial activity of pharbitin against phytopathogenic bacteria.

  7. Medical Devices; Immunology and Microbiology Devices; Classification of the Device To Detect and Identify Microbial Pathogen Nucleic Acids in Cerebrospinal Fluid. Final order.

    Science.gov (United States)

    2017-10-20

    The Food and Drug Administration (FDA or we) is classifying the device to detect and identify microbial pathogen nucleic acids in cerebrospinal fluid into class II (special controls). The special controls that will apply to the device type are identified in this order and will be part of the codified language for the device to detect and identify microbial pathogen nucleic acids in cerebrospinal fluid’s classification. We are taking this action because we have determined that classifying the device into class II (special controls) will provide a reasonable assurance of safety and effectiveness of the device. We believe this action will also enhance patients' access to beneficial innovative devices, in part by reducing regulatory burdens.

  8. Different types of stainless steel used in equipment in meat plants do not affect the initial microbial transfer, including pathogens, from pork skin.

    Science.gov (United States)

    Larivière-Gauthier, Guillaume; Quessy, Sylvain; Fournaise, Sylvain; Letellier, Ann; Fravalo, Philippe

    2015-07-01

    This study describes and measures the impact of different compositions and finishes of stainless steel used in equipment in the meat industry on the transfer of natural flora and selected pathogens from artificially contaminated pork skin. It is known that the adhesion to surfaces of Listeria monocytogenes and Salmonella, 2 pathogens frequently found in contaminated pork meat, depends on the nature and roughness of the surface. Our results show no statistically significant differences in microbial transfer regardless of the types of stainless steel considered, with the highest measured transfer difference being 0.18 log colony-forming units (CFUs)/800 cm(2). Moreover, no differences in total microbial community were observed after transfer on the 5 types of stainless steel using single-strand conformation polymorphism (SSCP). It was concluded that the different characteristics of the stainless steel tested did not affect the initial bacterial transfer in this study.

  9. Complete genome sequence of Bacillus velezensis M75, a biocontrol agent against fungal plant pathogens, isolated from cotton waste.

    Science.gov (United States)

    Kim, Sang Yoon; Lee, Sang Yeob; Weon, Hang-Yeon; Sang, Mee Kyung; Song, Jaekyeong

    2017-01-10

    Bacillus species have been widely used as biological control agents in agricultural fields due to their ability to suppress plant pathogens. Bacillus velezensis M75 was isolated from cotton waste used for mushroom cultivation in Korea, and was found to be antagonistic to fungal plant pathogens. Here, we report the complete genome sequence of the M75 strain, which has a 4,007,450-bp single circular chromosome with 3921 genes and a G+C content of 46.60%. The genome contained operons encoding various non-ribosomal peptide synthetases and polyketide synthases, which are responsible for the biosynthesis of secondary metabolites. Our results will provide a better understanding of the genome of B. velezensis strains for their application as biocontrol agents against fungal plant pathogens in agricultural fields. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Laboratory simulation reveals significant impacts of ocean acidification on microbial community composition and host-pathogen interactions between the blood clam and Vibrio harveyi.

    Science.gov (United States)

    Zha, Shanjie; Liu, Saixi; Su, Wenhao; Shi, Wei; Xiao, Guoqiang; Yan, Maocang; Liu, Guangxu

    2017-12-01

    It has been suggested that climate change may promote the outbreaks of diseases in the sea through altering the host susceptibility, the pathogen virulence, and the host-pathogen interaction. However, the impacts of ocean acidification (OA) on the pathogen components of bacterial community and the host-pathogen interaction of marine bivalves are still poorly understood. Therefore, 16S rRNA high-throughput sequencing and host-pathogen interaction analysis between blood clam (Tegillarca granosa) and Vibrio harveyi were conducted in the present study to gain a better understanding of the ecological impacts of ocean acidification. The results obtained revealed a significant impact of ocean acidification on the composition of microbial community at laboratory scale. Notably, the abundance of Vibrio, a major group of pathogens to many marine organisms, was significantly increased under ocean acidification condition. In addition, the survival rate and haemolytic activity of V. harveyi were significantly higher in the presence of haemolymph of OA treated T. granosa, indicating a compromised immunity of the clam and enhanced virulence of V. harveyi under future ocean acidification scenarios. Conclusively, the results obtained in this study suggest that future ocean acidification may increase the risk of Vibrio pathogen infection for marine bivalve species, such as blood clams. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. ANTIMICROBIAL ACTIVITY OF ETHANOL EXTRACT OF SATUREJA HORTENSIS L. TOWARDS PATHOGENIC MICROBIAL STRAINS

    Directory of Open Access Journals (Sweden)

    Kotyuk L. A.

    2014-12-01

    Full Text Available The paper provides the information on the component composition of ethereal oil of Satureja hortensis cultivated in Zhytomyr Polissya. In the ethereal oil of summer savory, 19 components were identified: carvacrol (89,07%, γ-terpinene (3,53%, α-thujone (1,7%, camphora (1,48%, terpinen-4 ol 4 (0,91%, β-bisabolen (0,56%, β-caryophyllene (0,45%, bitsiklogermakren (0,38% para-cymene (0,34%, 1,8-cineole (0,33%, trans-sabinengidrat (0.25%, 1-octen-3-ol (0.20%, spatulenol (0,18%, β-thujone (0,14%, eugenol (0,11%, geranylacetate (0,11%, humulene (0,09%, α-terpinene (0,09%, octanol-3 (0,07%. A high carvacrol content determines antimicrobial properties of summer savory. The antimicrobial activity of S. hortensis extract was studied in accordance with the common methodology of determining the sensitivity of microorganisms to antibacterial preparations. The aboveground part of plants harvested in the last ten-day period of August, in the flowering phase, was used in the experiments. The raw material was reduced to fragments of 1-1.5mm according to the requirements of pharmacopoeia. The extract of S. hortensis was obtained by the method of maceration in 40% ethyl alcohol at a ratio of 1:5 and the concentration of 200mg/ml. The availability of antimicrobial activity of extracted substances in the structure of the substances studied was determined by the way of comparison of their minimum inhibiting concentrations (MIC and minimum bactericidal/fungicidal concentrations (MBC/MFC with those in 40% ethyl alcohol. The paper investigates the biological activity of 40 % ethanol extract of Satureja hortensis herb grown under the conditions of Ukrainian Polissya as to golden staphylococcus (Staphylococcus aureus, coliform bacillus Escherichia coli, Pseudomonas aeruginosa and Candida albicans which are pathogenic in reference to other organisms. It has been shown that S. hortensis extract was characterized by antimicrobial activity since extracted substances

  12. Isolation and characterization of virus of highly pathogenic avian influenza H5 subtype of chicken from outbreaks in Indonesia

    Directory of Open Access Journals (Sweden)

    Agus Wiyono

    2004-03-01

    Full Text Available A study on the isolation and characterization of Highly Pathogenic Avian Influenza of chicken from outbreaks in Indonesia was conducted at Indonesian Research Institute for Veterinary Science. Outbreaks of avian disease had been reported in Indonesia since August 2003 affecting commercial layer, broiler, quail, and ostrich and also native chicken with showing clinical signs such as cyanosis of wattle and comb, nasal discharges and hypersalivation, subcutaneous ptechiae on foot and leg, diarre and sudden high mortality. The aim of this study is to isolate and characterize the causal agent of the disease. Samples of serum, feather follicle, tracheal swab, as well as organs of proventriculus, intestine, caecal tonsil, trachea and lungs were collected from infected animals. Serum samples were tested haemaglutination/haemaglutination inhibition to Newcastle Disease and Egg Drop Syndrome viruses. Isolation of virus of the causal agent of the outbreak was conducted from samples of feather follicle, tracheal swab, and organs using 11 days old specific pathogen free (SPF embryonated eggs. The isolated viruses were then characterised by agar gel precipitation test using swine influenza reference antisera, by haemaglutination inhibition using H1 to H15 reference antisera, and by electron microscope examination. The pathogenicity of the viruses was confirmed by intravenous pathogenicity index test and its culture in Chicken Embryo Fibroblast primary cell culture without addition of trypsin. The study revealed that the causative agent of the outbreaks of avian disease in Indonesia was avian influenza H5 subtype virus based upon serological tests, virus isolation and characterization using swine influenza reference antisera, and electron microscope examination. While subtyping of the viruses using H1 to H15 reference antisera suggested that the virus is very likely to be an avian influenza H5N1 subtype virus. The pathogenicity test confirmed that the viruses

  13. Isolation and identification of highly pathogenic avian influenza virus subtype H5N1 in peafowl (Pavo cristatus).

    Science.gov (United States)

    Ismail, Mahmoud Moussa; Khan, Owais Ahmed; Cattoli, Giovanni; Lu, Huaguang

    2010-03-01

    An outbreak of highly pathogenic avian influenza (HPAI) virus subtype H5N1 was first diagnosed in a "backyard" flock of peafowl (Pavo cristatus) raised on palace premises in the Kingdom of Saudi Arabia in December 3, 2007. The flock consisted of 40 peafowl, and their ages ranged from 3 to 5 years old. Affected birds suffered from depression, anorexia, and white diarrhea. Four dead birds were submitted for HPAI diagnosis at the Central Veterinary Diagnostic Laboratory in Riyadh. Brain and liver tissues and tracheal and cloacal swabs were taken from the dead birds and processed for a real-time reverse transcriptase (RT)-PCR test and virus isolation in specific-pathogen-free embryonating chicken eggs. The H5N1 subtype of avian influenza virus was isolated from the four dead birds and identified by a real-time RT-PCR before and after egg inoculation. The virus isolates were characterized as HPAI H5N1 virus by sequencing analysis. Phylogenetic comparisons revealed that the H5N1 viruses isolated from peafowl belong to the genetic clade 2.2 according to the World Health Organization nomenclature. The peafowl H5N1 virus falls into 2.2.2 sublineage II and clusters with the H5N1 viruses isolated from poultry in Saudi Arabia in 2007-08.

  14. Short communication: Molecular characteristics, antimicrobial susceptibility, and pathogenicity of clinical Nocardia cyriacigeorgica isolates from an outbreak of bovine mastitis.

    Science.gov (United States)

    Chen, Wei; Liu, Yongxia; Barkema, Herman W; Gao, Jian; De Buck, Jeroen; Kastelic, John P; Liu, Gang; Ali, Tariq; Shahid, Muhammad; Han, Bo

    2017-10-01

    The occurrence of nocardial mastitis, mostly in the context of outbreaks, has been reported in many countries. However, there is a paucity of reports regarding detailed characterization of Nocardia cyriacigeorgica from bovine mastitis. Thus, herein we report characteristics, antimicrobial susceptibility patterns, molecular identification, and pathogenicity of N. cyriacigeorgica isolated from an outbreak of clinical mastitis in a dairy herd in northern China. A total of 182 (80.2%) lactating cows had clinical mastitis with severe inflammation and firmness of the udder, reduced milk production, and anorexia, with no apparent clinical response to common antibiotics. Out of 22 mastitic milk samples submitted to our laboratory, 12 N. cyriacigeorgica were isolated and characterized using standard microbiological analysis, 16S rRNA gene sequencing, random amplified polymorphic DNA PCR analysis, biochemical assays, and antibiotic susceptibility testing. Additionally, in vivo experiments were done to determine pathogenicity of these clinical mastitis isolates. All isolates were resistant to ampicillin, amoxicillin-clavulanic acid, ciprofloxacin, minocycline, rifampicin, and aminoglycosides (type VI pattern). Additionally, intramammary inoculation of mice with N. cyriacigeorgica caused chronic inflammatory changes, including hyperemia, edema, and infiltration of lymphocytes and neutrophils, as well as hyperplasia of lymph nodules in mammary glands. Therefore, we concluded that N. cyriacigeorgica was involved in the current outbreak of mastitis. To our best knowledge, this is the first report to characterize N. cyriacigeorgica isolated from cases of bovine mastitis in China. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. Pattern of Bacterial Pathogens and Their Susceptibility Isolated from Surgical Site Infections at Selected Referral Hospitals, Addis Ababa, Ethiopia

    Directory of Open Access Journals (Sweden)

    Walelign Dessie

    2016-01-01

    Full Text Available Background. The emergence of multidrug resistant bacterial pathogens in hospitals is becoming a challenge for surgeons to treat hospital acquired infections. Objective. To determine bacterial pathogens and drug susceptibility isolated from surgical site infections at St. Paul Specialized Hospital Millennium Medical College and Yekatit 12 Referral Hospital Medical College, Addis Ababa, Ethiopia. Methods. A cross-sectional study was conducted between October 2013 and March 2014 on 107 surgical site infected patients. Wound specimens were collected using sterile cotton swab and processed as per standard operative procedures in appropriate culture media; and susceptibility testing was done using Kirby-Bauer disc diffusion technique. The data were analyzed by using SPSS version 20. Result. From a total of 107 swabs collected, 90 (84.1% were culture positive and 104 organisms were isolated. E. coli (24 (23.1% was the most common organism isolated followed by multidrug resistant Acinetobacter species (23 (22.1%. More than 58 (75% of the Gram negative isolates showed multiple antibiotic resistance (resistance ≥ 5 drugs. Pan-antibiotic resistance was noted among 8 (34.8% Acinetobacter species and 3 (12.5% E. coli. This calls for abstinence from antibiotic abuse. Conclusion. Gram negative bacteria were the most important isolates accounting for 76 (73.1%. Ampicillin, amoxicillin, penicillin, cephazoline, and tetracycline showed resistance while gentamicin and ciprofloxacin were relatively effective antimicrobials.

  16. Pathogenicity of local isolate virus BHV-1 as the aetiological agent of Infectious Bovine Rhinotracheitis in Bali Cattle

    Directory of Open Access Journals (Sweden)

    Rini I Damayanti

    2005-10-01

    Full Text Available Infectious Bovine Rhinotracheitis is a disease of cattle characterised by clinical signs of the upper respiratory tract, reproductive tract and nervous system. A study to define the pathogenicity of four BHV-1 local isolates has been conducted. Fourteen Bali cattle that were free of BHV-1 has been selected and divided into four treatment groups. Each group of three was infected with virus isolate I, II, III and IV respectively with approximately a dose of 108TCID50 /10 ml and two cattle were used as control animals. Isolate I and III were originated from semen from IBR positive bulls number G 867 and G 148 respectively whereas isolate II was collected from vaginal mucosa and isolate IV was from nasal mucosa of IBR positive cattle treated with dexamethasone. Clinical response, gross-pathological and histopathological changes were observed. Immunohistochemical staining was applied to detect the antigen in tissue section. The results show that the BHV-1 local isolates could produce IBR syndrome namely fever and changes in the respiratory and reproductive tracts even though the clinical responses seemed to be disappeared by 21 days PI. Grossly there were hyperaemic nasal and vaginal mucosa and pneumonia whereas histologically there were non suppurative rhinitis, tracheitis, pneumonia and vulvovaginitis. Immunohistochemically the antigen was detected in the nasal concha and trachea. Dexamethasone treatment at 60-64 days PI could produce less severe clinical features and the second necroppsy at 69 days PI also results in less severe pathological responses. The findings also suggest that the pathogenicity of BHV-1 local isolates were as follows: isolates I, II, IV and III.

  17. Isolation, characterization and HPLC quantification of compounds from Aquilegia fragrans Benth: Their in vitro antibacterial activities against bovine mastitis pathogens.

    Science.gov (United States)

    Mushtaq, Saleem; Aga, Mushtaq A; Qazi, Parvaiz H; Ali, Md Niamat; Shah, Aabid Manzoor; Lone, Sajad Ahmad; Shah, Aiyatullah; Hussain, Aehtesham; Rasool, Faheem; Dar, Hafizullah; Shah, Zeeshan Hamid; Lone, Shabir H

    2016-02-03

    The underground parts of Aquilegia fragrans are traditionally used for the treatment of wounds and various inflammatory diseases like bovine mastitis. However, there are no reports on the phytochemical characterization and antibacterial studies of A. fragrans. To isolate compounds from the methanol extract of the underground parts of A. fragrans and determine their antibacterial activity against the pathogens of bovine mastitis. The study was undertaken in order to scientifically validate the traditional use of A. fragrans. Five compounds were isolated from the methanol extract of the underground parts of A. fragrans using silica gel column chromatography. Structural elucidation of the isolated compounds was done using spectral data analysis and comparison with literature. High performance liquid chromatography (HPLC) was used for the qualitative and quantitative determination of isolated compounds in the crude methanol extract. The methanol extract and isolated compounds were evaluated for antibacterial activities against mastitis pathogens using broth micro-dilution technique. The five isolated compounds were identified as (1) 2, 4-dihydroxyphenylacetic acid methyl ester (2) β-sitosterol (3) Aquilegiolide (4) Glochidionolactone-A and (5) Magnoflorine. A quick and sensitive HPLC method was developed for the first time for qualitative and quantitative determination of four isolated marker compounds from A. fragrans. The crude methanol extract and compound 5 exhibited weak antibacterial activities that varied between the bacterial species (MIC=500-3000 µg/ml). The above results show that the crude methanol extract and isolated compounds from A. fragrans exhibit weak antibacterial activities. Further phytochemical and pharmacological studies are required for proper scientific validation of the folk use of this plant species in the treatment of various inflammatory diseases like bovine mastitis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. ANTIMICROBIAL ACTIVITY OF ETHANOL EXTRACT OF SATUREJA HORTENSIS L. TOWARDS PATHOGENIC MICROBIAL STRAINS

    Directory of Open Access Journals (Sweden)

    L. A. Kotyuk

    2014-12-01

    Full Text Available The paper provides the information on the component composition of ethereal oil of Satureja hortensis cultivated in Zhytomyr Polissya. In the ethereal oil of summer savory, 19 components were identified: carvacrol (89,07%, γ-terpinene (3,53%, α-thujone (1,7%, camphora (1,48%, terpinen-4 ol 4 (0,91%, β-bisabolen (0,56%, β-caryophyllene (0,45%, bitsiklogermakren (0,38% para-cymene (0,34%, 1,8-cineole (0,33%, trans-sabinengidrat (0.25%, 1-octen-3-ol (0.20%, spatulenol (0,18%, β-thujone (0,14%, eugenol (0,11%, geranylacetate (0,11%, humulene (0,09%, α-terpinene (0,09%, octanol-3 (0,07%. A high carvacrol content determines antimicrobial properties of summer savory. The antimicrobial activity of S. hortensis extract was studied in accordance with the common methodology of determining the sensitivity of microorganisms to antibacterial preparations. The aboveground part of plants harvested in the last ten-day period of August, in the flowering phase, was used in the experiments. The raw material was reduced to fragments of 1-1.5mm according to the requirements of pharmacopoeia. The extract of S. hortensis was obtained by the method of maceration in 40% ethyl alcohol at a ratio of 1:5 and the concentration of 200mg/ml. The availability of antimicrobial activity of extracted substances in the structure of the substances studied was determined by the way of comparison of their minimum inhibiting concentrations (MIC and minimum bactericidal/fungicidal concentrations (MBC/MFC with those in 40% ethyl alcohol. The paper investigates the biological activity of 40 % ethanol extract of Satureja hortensis herb grown under the conditions of Ukrainian Polissya as to golden staphylococcus (Staphylococcus aureus, coliform bacillus Escherichia coli, Pseudomonas aeruginosa and Candida albicans which are pathogenic in reference to other organisms. It has been shown that S. hortensis extract was characterized by antimicrobial activity since extracted substances

  19. Draft genome sequence of the first human isolate of the ruminant pathogen Mycoplasma capricolum subsp. capricolum

    DEFF Research Database (Denmark)

    Seersholm, Frederik Valeur; Fischer, Anne; Heller, Martin

    2015-01-01

    Mycoplasma capricolum subsp. capricolum is a well-known pathogen of small ruminants. A recent human case of septicemia involving this agent raised the question of its potential pathogenicity to humans. We present the first draft genome sequence of a human Mycoplasma capricolum subsp. capricolum...

  20. FishPathogens.eu/vhsv: a user-friendly viral haemorrhagic septicaemia virus isolate and sequence database

    DEFF Research Database (Denmark)

    Jonstrup, Søren Peter; Gray, Tanya; Kahns, Søren

    2009-01-01

    A database has been created, http://www.Fish Pathogens.eu, with the aim of providing a single repository for collating important information on significant pathogens of aquaculture, relevant to their control and management. This database will be developed, maintained and managed as part of the Eu......A database has been created, http://www.Fish Pathogens.eu, with the aim of providing a single repository for collating important information on significant pathogens of aquaculture, relevant to their control and management. This database will be developed, maintained and managed as part...... of the European Community Reference Laboratory for Fish Diseases function. This concept has been initially developed for viral haemorrhagic septicaemia virus and will be extended in future to include information on other significant aquaculture pathogens. Information included for each isolate comprises sequence...... to obtain data from any selected part of the genome of interest. The output of the sequence search can be readily retrieved as a FASTA file ready to be imported into a sequence alignment tool of choice, facilitating further molecular epidemiological study....

  1. Antifungal activity of schinol and a new biphenyl compound isolated from Schinus terebinthifolius against the pathogenic fungus Paracoccidioides brasiliensis.

    Science.gov (United States)

    Johann, Susana; Sá, Nívea P; Lima, Luciana A R S; Cisalpino, Patricia S; Cota, Betania B; Alves, Tânia M A; Siqueira, Ezequias P; Zani, Carlos L

    2010-10-12

    The aim of this study was to isolate and identify the antifungal compounds from the extracts of Schinus terebinthifolius (Anacardiaceae) against clinical isolates of the pathogenic fungus Paracoccidioides brasiliensis. The hexane and dichlomethane fractions from leaves and stems of S. terebinthifolius were fractionated using several chromatography techniques to afford four compounds. The compounds isolated from S. terebinthifolius were identified as schinol (1), a new biphenyl compound, namely, 4'-ethyl-4-methyl-2,2',6,6'-tetrahydroxy[1,1'-biphenyl]-4,4'-dicarboxylate (2), quercetin (3), and kaempferol (4). Compounds 1 and 2 were active against different strains of P. brasiliensis, showing a minimal inhibitory concentration value against the isolate Pb B339 of 15.6 μg/ml. The isolate Pb 1578 was more sensitive to compound 1 with a MIC value of 7.5 μg/ml. Schinol presented synergistic effect only when combined with itraconazole. The compounds isolated from S. terebinthifolius were not able to inhibit cell wall synthesis or assembly using the sorbitol assay. This work reveals for the first time the occurrence of compound 2 and discloses activity of compounds 1 and 2 against several clinical isolates of P. brasiliensis. These results justify further studies to clarify the mechanisms of action of these compounds.

  2. Pattern of pathogens and their sensitivity isolated from superficial surgical site infections in a tertiary care hospital

    International Nuclear Information System (INIS)

    Ali, S.A.; Tahir, S.M.; Shaikh, N.A.

    2009-01-01

    Infection is an important cause of morbidity and mortality in surgical patients. Rapidly emerging nosocomial pathogens and the problem of multi-drug resistance necessitates periodic review of isolation patterns and sensitivity in surgical practice. Surgical site infections (SSI) are defined as an infections that occurs at the incision site within thirty days after surgery. Objectives of the study were to determine the pattern of pathogens involved and their antibiotic sensitivity isolated from superficial surgical site infections in a teaching hospital. This observational study was conducted for 1 year from January 2008 to December 2008 in all 4 surgical units of Liaquat University Hospital Hyderabad which caters to patients from low socioeconomic status. Pus culture and sensitivity reports were collected prospectively from hospitalised patients who developed postoperative wound infection. The patients who developed fecal/biliary/urinary fistula or operated for malignancies, and with negative cultures were excluded from the study. Analysis was carried out using SPSS 10. During the study period 112 pus culture and sensitivity reports were analyzed. E. coli 68 (60.7%) was the most common organism isolated followed by Klebsiella 23 (20.5%). The least frequent organism was staph. Epidermidis 1 (0.9%). All isolates were sensitive to penicillin derivatives and carbapenem. Quinolones, Aminoglycosides and Monobactum were also showing some promise in our study. However, Cephalosporins were ineffective against most of the important isolates in our study. E. coli and klebsiella were the most important isolates form SSI in our study, and penicillin derivatives and carbapenem were showing 100% antibiotic sensitivity to all of the isolates. (author)

  3. Genomic and Phenotypic Variation in Morphogenetic Networks of Two Candida albicans Isolates Subtends Their Different Pathogenic Potential

    Directory of Open Access Journals (Sweden)

    Duccio Cavalieri

    2018-01-01

    Full Text Available The transition from commensalism to pathogenicity of Candida albicans reflects both the host inability to mount specific immune responses and the microorganism’s dimorphic switch efficiency. In this study, we used whole genome sequencing and microarray analysis to investigate the genomic determinants of the phenotypic changes observed in two C. albicans clinical isolates (YL1 and YQ2. In vitro experiments employing epithelial, microglial, and peripheral blood mononuclear cells were thus used to evaluate C. albicans isolates interaction with first line host defenses, measuring adhesion, susceptibility to phagocytosis, and induction of secretory responses. Moreover, a murine model of peritoneal infection was used to compare the in vivo pathogenic potential of the two isolates. Genome sequence and gene expression analysis of C. albicans YL1 and YQ2 showed significant changes in cellular pathways involved in environmental stress response, adhesion, filamentous growth, invasiveness, and dimorphic transition. This was in accordance with the observed marked phenotypic differences in biofilm production, dimorphic switch efficiency, cell adhesion, invasion, and survival to phagocyte-mediated host defenses. The mutations in key regulators of the hyphal growth pathway in the more virulent strain corresponded to an overall greater number of budding yeast cells released. Compared to YQ2, YL1 consistently showed enhanced pathogenic potential, since in vitro, it was less susceptible to ingestion by phagocytic cells and more efficient in invading epithelial cells, while in vivo YL1 was more effective than YQ2 in recruiting inflammatory cells, eliciting IL-1β response and eluding phagocytic cells. Overall, these results indicate an unexpected isolate-specific variation in pathways important for host invasion and colonization, showing how the genetic background of C. albicans may greatly affect its behavior both in vitro and in vivo. Based on this approach, we

  4. Human neutrophil clearance of bacterial pathogens triggers anti-microbial γδ T cell responses in early infection.

    Directory of Open Access Journals (Sweden)

    Martin S Davey

    2011-05-01

    Full Text Available Human blood Vγ9/Vδ2 T cells, monocytes and neutrophils share a responsiveness toward inflammatory chemokines and are rapidly recruited to sites of infection. Studying their interaction in vitro and relating these findings to in vivo observations in patients may therefore provide crucial insight into inflammatory events. Our present data demonstrate that Vγ9/Vδ2 T cells provide potent survival signals resulting in neutrophil activation and the release of the neutrophil chemoattractant CXCL8 (IL-8. In turn, Vγ9/Vδ2 T cells readily respond to neutrophils harboring phagocytosed bacteria, as evidenced by expression of CD69, interferon (IFN-γ and tumor necrosis factor (TNF-α. This response is dependent on the ability of these bacteria to produce the microbial metabolite (E-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP, requires cell-cell contact of Vγ9/Vδ2 T cells with accessory monocytes through lymphocyte function-associated antigen-1 (LFA-1, and results in a TNF-α dependent proliferation of Vγ9/Vδ2 T cells. The antibiotic fosmidomycin, which targets the HMB-PP biosynthesis pathway, not only has a direct antibacterial effect on most HMB-PP producing bacteria but also possesses rapid anti-inflammatory properties by inhibiting γδ T cell responses in vitro. Patients with acute peritoneal-dialysis (PD-associated bacterial peritonitis--characterized by an excessive influx of neutrophils and monocytes into the peritoneal cavity--show a selective activation of local Vγ9/Vδ2 T cells by HMB-PP producing but not by HMB-PP deficient bacterial pathogens. The γδ T cell-driven perpetuation of inflammatory responses during acute peritonitis is associated with elevated peritoneal levels of γδ T cells and TNF-α and detrimental clinical outcomes in infections caused by HMB-PP positive microorganisms. Taken together, our findings indicate a direct link between invading pathogens, neutrophils, monocytes and microbe-responsive γδ T cells in

  5. Human Neutrophil Clearance of Bacterial Pathogens Triggers Anti-Microbial γδ T Cell Responses in Early Infection

    Science.gov (United States)

    Roberts, Gareth W.; Heuston, Sinéad; Brown, Amanda C.; Chess, James A.; Toleman, Mark A.; Gahan, Cormac G. M.; Hill, Colin; Parish, Tanya; Williams, John D.; Davies, Simon J.; Johnson, David W.; Topley, Nicholas; Moser, Bernhard; Eberl, Matthias

    2011-01-01

    Human blood Vγ9/Vδ2 T cells, monocytes and neutrophils share a responsiveness toward inflammatory chemokines and are rapidly recruited to sites of infection. Studying their interaction in vitro and relating these findings to in vivo observations in patients may therefore provide crucial insight into inflammatory events. Our present data demonstrate that Vγ9/Vδ2 T cells provide potent survival signals resulting in neutrophil activation and the release of the neutrophil chemoattractant CXCL8 (IL-8). In turn, Vγ9/Vδ2 T cells readily respond to neutrophils harboring phagocytosed bacteria, as evidenced by expression of CD69, interferon (IFN)-γ and tumor necrosis factor (TNF)-α. This response is dependent on the ability of these bacteria to produce the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP), requires cell-cell contact of Vγ9/Vδ2 T cells with accessory monocytes through lymphocyte function-associated antigen-1 (LFA-1), and results in a TNF-α dependent proliferation of Vγ9/Vδ2 T cells. The antibiotic fosmidomycin, which targets the HMB-PP biosynthesis pathway, not only has a direct antibacterial effect on most HMB-PP producing bacteria but also possesses rapid anti-inflammatory properties by inhibiting γδ T cell responses in vitro. Patients with acute peritoneal-dialysis (PD)-associated bacterial peritonitis – characterized by an excessive influx of neutrophils and monocytes into the peritoneal cavity – show a selective activation of local Vγ9/Vδ2 T cells by HMB-PP producing but not by HMB-PP deficient bacterial pathogens. The γδ T cell-driven perpetuation of inflammatory responses during acute peritonitis is associated with elevated peritoneal levels of γδ T cells and TNF-α and detrimental clinical outcomes in infections caused by HMB-PP positive microorganisms. Taken together, our findings indicate a direct link between invading pathogens, neutrophils, monocytes and microbe-responsive γδ T cells in early

  6. Pathogenic characteristics of Candida albicans isolated from oral cavities of denture wearers and cancer patients wearing oral prostheses.

    Science.gov (United States)

    Mothibe, J V; Patel, M

    2017-09-01

    Candida albicans cause opportunistic infections including oral candidiasis in immunocompromised patients. It has an ability to cause infection due to its virulence factors. This study investigated the pathogenic characteristics of C. albicans isolated from the oral cavities of healthy subjects and two vulnerable groups, denture wearers and cancer patients wearing oral prostheses. Oral rinse samples were collected and cultured for the quantitative and qualitative analysis of Candida. Twenty strains of C. albicans isolated from the healthy individuals and denture wearers and, 14 strains isolated from the cancer patients were selected and their pathogenic characteristics were measured. The results of the study groups were compared using a Scheffe test for pairwise comparison and a chi square test. Denture wearer and cancer patients with prostheses carried significantly higher number (p production were significantly higher in the strains from denture wearers. In addition, high number of isolates from the denture wearers produced phospholipase and proteinase (85% and 80% respectively) compared to the strains from normal subjects (25% and 60% respectively). Only the germ tube formation and adherence ability were significantly higher in the strains from the cancer patients with prostheses (p = 0.05 and p oral cavity and prostheses is important in the prevention of colonization of Candida and the development of oral candidiasis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Susceptibility to antimicrobial agents among bovine mastitis pathogens isolated from North American dairy cattle, 2002-2010.

    Science.gov (United States)

    Lindeman, Cynthia J; Portis, Ellen; Johansen, Lacie; Mullins, Lisa M; Stoltman, Gillian A

    2013-09-01

    Approximately 8,000 isolates of Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis, Staphylococcus aureus, and Escherichia coli, isolated by 25 veterinary laboratories across North America between 2002 and 2010, were tested for in vitro susceptibility to beta-lactam, macrolide, and lincosamide drugs. The minimal inhibitory concentrations (MICs) of the beta-lactam drugs remained low against most of the Gram-positive strains tested, and no substantial changes in the MIC distributions were seen over time. Of the beta-lactam antimicrobial agents tested, only ceftiofur showed good in vitro activity against E. coli. The MICs of the macrolides and lincosamides also remained low against Gram-positive mastitis pathogens. While the MIC values given by 50% of isolates (MIC50) for erythromycin and pirlimycin and the streptococci were all low (≤0.5 µg/ml), the MIC values given by 90% of isolates (MIC90) were higher and more variable, but with no apparent increase over time. Staphylococcus aureus showed little change in erythromycin susceptibility over time, but there may be a small, numerical increase in pirlimycin MIC50 and MIC90 values. Overall, the results suggest that mastitis pathogens in the United States and Canada have not shown any substantial changes in the in vitro susceptibility to beta-lactam, macrolide, and lincosamide drugs tested over the 9 years of the study.

  8. Use of amplicon sequencing to improve sensitivity in PCR-based detection of microbial pathogen in environmental samples.

    Science.gov (United States)

    Saingam, Prakit; Li, Bo; Yan, Tao

    2018-06-01

    DNA-based molecular detection of microbial pathogens in complex environments is still plagued by sensitivity, specificity and robustness issues. We propose to address these issues by viewing them as inadvertent consequences of requiring specific and adequate amplification (SAA) of target DNA molecules by current PCR methods. Using the invA gene of Salmonella as the model system, we investigated if next generation sequencing (NGS) can be used to directly detect target sequences in false-negative PCR reaction (PCR-NGS) in order to remove the SAA requirement from PCR. False-negative PCR and qPCR reactions were first created using serial dilutions of laboratory-prepared Salmonella genomic DNA and then analyzed directly by NGS. Target invA sequences were detected in all false-negative PCR and qPCR reactions, which lowered the method detection limits near the theoretical minimum of single gene copy detection. The capability of the PCR-NGS approach in correcting false negativity was further tested and confirmed under more environmentally relevant conditions using Salmonella-spiked stream water and sediment samples. Finally, the PCR-NGS approach was applied to ten urban stream water samples and detected invA sequences in eight samples that would be otherwise deemed Salmonella negative. Analysis of the non-target sequences in the false-negative reactions helped to identify primer dime-like short sequences as the main cause of the false negativity. Together, the results demonstrated that the PCR-NGS approach can significantly improve method sensitivity, correct false-negative detections, and enable sequence-based analysis for failure diagnostics in complex environmental samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Phenotypic Variation Is Almost Entirely Independent of the Host-Pathogen Relationship in Clinical Isolates of S. aureus.

    Directory of Open Access Journals (Sweden)

    Adrian D Land

    Full Text Available A key feature of Staphylococcus aureus biology is its ability to switch from an apparently benign colonizer of ~30% of the population to a cutaneous pathogen, to a deadly invasive pathogen. Little is known about the mechanisms driving this transition or the propensity of different S. aureus strains to engender different types of host-pathogen interactions. At the same time, significant weight has been given to the role of specific in vitro phenotypes in S. aureus virulence. Biofilm formation, hemolysis and pigment formation have all been associated with virulence in mice.To determine if there is a correlation between in vitro phenotype and the three types of host-pathogen relationships commonly exhibited by S. aureus in the context of its natural human host, we assayed 300 clinical isolates for phenotypes implicated in virulence including hemolysis, sensitivity to autolysis, and biofilm formation. For comparative purposes, we also assayed phenotype in 9 domesticated S. aureus strains routinely used for analysis of virulence determinants in laboratory settings.Strikingly, the clinical strains exhibited significant phenotypic uniformity in each of the assays evaluated in this study. One exception was a small, but significant, correlation between an increased propensity for biofilm formation and isolation from skin and soft tissue infections (SSTIs. In contrast, we observed a high degree of phenotypic variation between common laboratory strains that exhibit virulence in mouse models. These data suggest the existence of significant evolutionary pressure on the S. aureus genome and highlight a role for host factors as a strong determinant of the host-pathogen relationship. In addition, the high degree of variation between laboratory strains emphasizes the need for caution when applying data obtained in one lab strain to the analysis of another.

  10. Biofilm formation by Salmonella Enteritidis and Salmonella Typhimurium isolated from avian sources is partially related with their in vivo pathogenicity.

    Science.gov (United States)

    Borges, Karen Apellanis; Furian, Thales Quedi; de Souza, Sara Neves; Menezes, Rafaela; de Lima, Diane Alves; Fortes, Flávia Bornancini Borges; Salle, Carlos Tadeu Pippi; Moraes, Hamilton Luiz Souza; Nascimento, Vladimir Pinheiro

    2018-03-22

    Salmonella Enteritidis and Salmonella Typhimurium are among the most prevalent serotypes isolated from salmonellosis outbreaks and poultry. Salmonella spp. have the capacity to form biofilms on several surfaces, which can favour survival in hostile environments, such as slaughterhouses. Salmonella strains present differences in pathogenicity. However, there is little information regarding the pathogenicity of S. Enteritidis and S. Typhimurium isolated from avian sources and their relationship to biofilm production. The aim of this study was to use a novel pathogenicity index and a biofilm production assay to evaluate their relationships within these serotypes. In addition, we detected the presence of the spiA and agfA genes in these strains. Biofilm formation was investigated at two temperatures (37 °C and 28 °C) using microtiter plate assay, and the results were compared with the individual pathogenicity index of each strain. PCR was used to detect spiA and agfA, virulence genes associated with biofilm production. S. Enteritidis and S. Typhimurium strains were capable of producing biofilm at 37 °C and 28 °C. Sixty-two percent and 59.5% of S. Enteritidis and 73.8% and 46.2% of S. Typhimurium produced biofilm at 37 °C and 28 °C, respectively. Biofilm production at 37 °C was significantly higher in both serotypes. Only S. Enteritidis was capable of adhering strongly at both temperatures. Biofilm production was related to pathogenicity index only at 28 °C for S. Enteritidis. spiA and agfA were found in almost all strains and were not statistically associated with biofilm production. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Isolation and identification of an extracellular subtilisin-like serine protease secreted by the bat pathogen Pseudogymnoascus destructans.

    Directory of Open Access Journals (Sweden)

    Evan L Pannkuk

    Full Text Available White nose syndrome (WNS is a cutaneous fungal disease of bats. WNS is responsible for unprecedented mortalities in North American cave bat populations. There have been few descriptions of enzyme activities that may function in WNS host/pathogen interactions, while no study has isolated and described secreted proteases. To address the hypothesis that Pseudogymnoascus destructans secretes extracellular proteases that function in wing necrosis during WNS infection, the object of this study was to culture P. destructans on various media, then isolate and structurally identify those proteases accumulated stably in the culture medium. We found a single dominant protease activity on minimal nutrient broth enriched with protein substrates, which was strongly inhibited by phenylmethylsulfonyl fluoride. This P. destructans serine protease (PdSP1 was isolated by preparative isoelectric focusing and concanavalin A lectin affinity chromatography. PdSP1 showed a molecular weight 27,900 (estimated by SDS-PAGE, broad pH optimum 6-8, and temperature optimum 60°C. Structural characterization of PdSP1 by MALDI-TOF MS, Orbitrap MS/MS, and Edman amino-terminal peptide sequencing matched it directly to a hypothetical protein accession from the sequenced P. destructans genome that is further identified as a MEROPS family S8A subtilisin-like serine peptidase. Two additional isoforms, PdSP2 and PdSP3, were identified in the P. destructans genome with 90% and 53% homology, respectively. P. destructans S8A serine proteases showed closer sequence conservation to P. pannorum and plant pathogenic fungi than to human pathogenic dermatophytes. Peptide-specific polyclonal antibodies developed from the PdSP1 sequence detected the protein in western blots. These subtilisin-like serine proteases are candidates for further functional studies in WNS host-pathogen interaction.

  12. Isolation and identification of an extracellular subtilisin-like serine protease secreted by the bat pathogen Pseudogymnoascus destructans.

    Science.gov (United States)

    Pannkuk, Evan L; Risch, Thomas S; Savary, Brett J

    2015-01-01

    White nose syndrome (WNS) is a cutaneous fungal disease of bats. WNS is responsible for unprecedented mortalities in North American cave bat populations. There have been few descriptions of enzyme activities that may function in WNS host/pathogen interactions, while no study has isolated and described secreted proteases. To address the hypothesis that Pseudogymnoascus destructans secretes extracellular proteases that function in wing necrosis during WNS infection, the object of this study was to culture P. destructans on various media, then isolate and structurally identify those proteases accumulated stably in the culture medium. We found a single dominant protease activity on minimal nutrient broth enriched with protein substrates, which was strongly inhibited by phenylmethylsulfonyl fluoride. This P. destructans serine protease (PdSP1) was isolated by preparative isoelectric focusing and concanavalin A lectin affinity chromatography. PdSP1 showed a molecular weight 27,900 (estimated by SDS-PAGE), broad pH optimum 6-8, and temperature optimum 60°C. Structural characterization of PdSP1 by MALDI-TOF MS, Orbitrap MS/MS, and Edman amino-terminal peptide sequencing matched it directly to a hypothetical protein accession from the sequenced P. destructans genome that is further identified as a MEROPS family S8A subtilisin-like serine peptidase. Two additional isoforms, PdSP2 and PdSP3, were identified in the P. destructans genome with 90% and 53% homology, respectively. P. destructans S8A serine proteases showed closer sequence conservation to P. pannorum and plant pathogenic fungi than to human pathogenic dermatophytes. Peptide-specific polyclonal antibodies developed from the PdSP1 sequence detected the protein in western blots. These subtilisin-like serine proteases are candidates for further functional studies in WNS host-pathogen interaction.

  13. Molecular serotyping, virulence gene profiling and pathogenicity of Streptococcus agalactiae isolated from tilapia farms in Thailand by multiplex PCR.

    Science.gov (United States)

    Kannika, K; Pisuttharachai, D; Srisapoome, P; Wongtavatchai, J; Kondo, H; Hirono, I; Unajak, S; Areechon, N

    2017-06-01

    This study aimed to biotype Streptococcus agalactiae isolated from tilapia farms in Thailand based on molecular biotyping methods and to determine the correlation between the serotype and virulence of bacteria. In addition to a biotyping (serotyping) technique based on multiplex PCR of cps genes, in this study, we developed multiplex PCR typing of Group B streptococcus (GBS) virulence genes to examine three clusters of virulence genes and their correlation with the pathogenicity of S. agalactiae. The epidemiology of S. agalactiae in Thailand was analysed to provide bacterial genetic information towards a future rational vaccine strategy for tilapia culture systems. Streptococcus agalactiae were isolated from diseased tilapia from different areas of Thailand. A total of 124 S. agalactiae isolates were identified by phenotypic analysis and confirmed by 16S rRNA PCR. Bacterial genotyping was conducted based on (i) molecular serotyping of the capsular polysaccharide (cps) gene cluster and (ii) virulence gene profiling using multiplex PCR analysis of 14 virulence genes (lmb, scpB, pavA, cspA, spb1, cyl, bca, rib, fbsA, fbsB, cfb, hylB, bac and pbp1A/ponA). Only serotypes Ia and III were found in this study; serotype Ia lacks the lmb, scpB and spb1 genes, whereas serotype III lacks only the bac gene. Virulence tests in juvenile Nile tilapia demonstrated a correlation between the pathogenicity of the bacteria and their virulence gene profile, with serotype III showing higher virulence than serotype Ia. Epidemiological analysis showed an almost equal distribution in all regions of Thailand, except serotype III was found predominantly in the southern areas. Only two serotypes of S. agalactiae were isolated from diseased tilapia in Thailand. Serotype Ia showed fewer virulence genes and lower virulence than serotype III. Both serotypes showed a similar distribution throughout Thailand. We identified two major serotypes of S. agalactiae isolates associated with the outbreak in

  14. Pathogenicity of Phytophthora species isolated from rhizosphere soil in the eastern United States

    Science.gov (United States)

    Y. Balci; S. Balci; W.L. MacDonald; K.W. Gottschalk

    2008-01-01

    Pathogenicity of seven Phytophthora species was assessed by inoculation of stem and foliar tissues of oak species (Quercus spp.) native to the eastern United States. Phytophthora cambivora, P. cinnamomi, P. citricola, P. europaea, P. quercina...

  15. Antimicrobial susceptibility monitoring of respiratory tract pathogens isolated from diseased cattle and pigs across Europe: the VetPath study.

    Science.gov (United States)

    de Jong, Anno; Thomas, Valérie; Simjee, Shabbir; Moyaert, Hilde; El Garch, Farid; Maher, Kirsty; Morrissey, Ian; Butty, Pascal; Klein, Ulrich; Marion, Hervé; Rigaut, Delphine; Vallé, Michel

    2014-08-06

    VetPath is an ongoing pan-European antibiotic susceptibility monitoring programme collecting pathogens from diseased antimicrobial non-treated cattle, pigs and poultry. In the current study, 1001 isolates from cattle and pig respiratory tract infections were tested for their antimicrobial susceptibilities. Non-replicate lung samples or nasopharyngeal/nasal swabs were collected from animals with acute clinical signs in 11 countries during 2002-2006. Pasteurella multocida and Mannheimia haemolytica from cattle and P. multocida, Actinobacillus pleuropneumoniae and Streptococcus suis from pigs were isolated by standard methods. S. suis was also isolated from meningitis cases. MICs of 16 antibiotics were assessed centrally by broth microdilution following CLSI recommendations. Results were interpreted using CLSI breakpoints where available. P. multocida (231) and M. haemolytica (138) isolates were all susceptible to amoxicillin/clavulanic acid, ceftiofur, enrofloxacin and trimethoprim/sulfamethoxazole. Resistance to florfenicol and spectinomycin was 0.4% and 3.5% in P. multocida, respectively, and absent in M. haemolytica isolates. Tetracycline resistance was 5.7% and 14.6% for P. multocida and M. haemolytica. In pigs, 230 P. multocida, 220 A. pleuropneumoniae and 182 S. suis isolates were recovered. Resistance to amoxicillin/clavulanic acid, ceftiofur, enrofloxacin, florfenicol, tiamulin and tilmicosin was absent or <1%. Trimethoprim/sulfamethoxazole resistance was 3-6% and tetracycline resistance varied from 14.7% in A. pleuropneumoniae to 81.8% in S. suis. In conclusion, low resistance to antibiotics with defined clinical breakpoints, except for tetracycline, was observed among the major respiratory tract pathogens recovered from cattle and pigs. Since for approximately half of the antibiotics in this panel no CLSI-defined breakpoints were available, setting of the missing veterinary breakpoints is important. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Bacteria isolated from parasitic nematodes - a potential novel vector of pathogens?

    OpenAIRE

    Lacharme-Lora, Lizeth; Salisbury, Vyv; Humphrey, Tom J.; Stafford, Kathryn; Perkins, Sarah E.

    2009-01-01

    Bacterial pathogens are ubiquitous in soil and water - concurrently so are free-living helminths that feed on bacteria. These helminths fall into two categories; the non-parasitic and the parasitic. The former have been the focus of previous work, finding that bacterial pathogens inside helminths are conferred survival advantages over and above bacteria alone in the environment, and that accidental ingestion of non-parasitic helminths can cause systemic infection in vertebrate hosts. Here, we...

  17. Phylogenetic relationships and pathogenicity variation of two Newcastle disease viruses isolated from domestic ducks in Southern China.

    Science.gov (United States)

    Kang, Yinfeng; Li, Yanling; Yuan, Runyu; Li, Xianwei; Sun, Minhua; Wang, Zhaoxiong; Feng, Minsha; Jiao, Peirong; Ren, Tao

    2014-08-12

    Newcastle disease (ND) is an OIE listed disease caused by virulent avian paramyxovirus type 1 (APMV-1) strains, which is enzootic and causes large economic losses in the poultry sector. Genotype VII and genotype IX NDV viruses were the predominant circulating genotype in China, which may possibly be responsible for disease outbreaks in chicken flocks in recent years. While ducks and geese usually have exhibited inapparent infections. In the present study, we investigate the complete genome sequence, the clinicopathological characterization and transmission of two virulent Newcastle disease viruses, SS-10 and NH-10, isolated from domestic ducks in Southern China in 2010. F, and the complete gene sequences based on phylogenetic analysis demonstrated that SS-10 (genotype VII) and NH-10 (genotype IX) belongs to class II. The deduced amino acid sequence was (112)R-R-Q-K/R-R-F(117) at the fusion protein cleavage site. Animal experiment results showed that the SS-10 virus isolated from ducks was highly pathogenic for chickens and geese, but low pathogenic for ducks. It could be detected from spleen, lung, kidney, trachea, small intestine, bursa of fabricius, thymus, pancreas and cecal tonsils, oropharyngeal and cloacal swabs, and could transmit to the naive contact birds. Moreover, it could transmit to chickens, ducks and geese by naive contact. However, the NH-10 virus isolated from ducks could infect some chickens, ducks and geese, but only caused chickens to die. Additionally, it could transmit to the naive contact chickens, ducks, and geese. The two NDV isolates exhibited different biological properties with respect to pathogenicity and transmission in chickens, ducks and geese. Therefore, no species-preference exists for chicken, duck or goose viruses and more attention should be paid to the trans-species transmission of VII NDVs between ducks, geese and chickens for the control and eradication of ND.

  18. Pathogenicity for onion and genetic diversity of isolates of the pathogenic fungus Colletotrichum gloeosporioides (Phyllachoraceae) from the State of Pernambuco, Brazil.

    Science.gov (United States)

    Nova, M X Vila; Borges, L R; de Sousa, A C B; Brasileiro, B T R V; Lima, E A L A; da Costa, A F; de Oliveira, N T

    2011-02-22

    Onion anthracnose, caused by Colletotrichum gloeosporioides, is one of the main diseases of onions in the State of Pernambuco. We examined the pathogenicity of 15 C. gloeosporioides strains and analyzed their genetic variability using RAPDs and internal transcribed spacers (ITS) of the rDNA region. Ten of the strains were obtained from substrates and hosts other than onion, including chayote (Sechium edule), guava (Psidium guajava), pomegranate (Punica granatum), water from the Capibaribe River, maracock (Passiflora sp), coconut (Cocus nucifera), surinam cherry (Eugenia uniflora), and marine soil; five isolates came from onions collected from four different regions of the State of Pernambuco and one region of the State of Amazonas. Pathogenicity tests were carried out using onion leaves and bulbs. All strains were capable of causing disease in leaves, causing a variable degree of lesions on the leaves; four strains caused the most severe damage. In the onion bulb tests, only three of the above strains caused lesions. Seven primers of arbitrary sequences were used in the RAPD analysis, generating polymorphic bands that allowed the separation of the strains into three distinct groups. The amplification products generated with the primers ITS1 and ITS4 also showed polymorphism when digested with three restriction enzymes, DraI, HaeIII and MspI. Only the latter two demonstrated genetic variations among the strains. These two types of molecular markers were able to differentiate the strain from the State of Amazonas from those of the State of Pernambuco. However, there was no relationship between groups of strains, based on molecular markers, and degree of pathogenicity for onion leaves and bulbs.

  19. No evidence of enemy release in pathogen and microbial communities of common wasps (Vespula vulgaris in their native and introduced range.

    Directory of Open Access Journals (Sweden)

    Philip J Lester

    Full Text Available When invasive species move to new environments they typically experience population bottlenecks that limit the probability that pathogens and parasites are also moved. The invasive species may thus be released from biotic interactions that can be a major source of density-dependent mortality, referred to as enemy release. We examined for evidence of enemy release in populations of the common wasp (Vespula vulgaris, which attains high densities and represents a major threat to biodiversity in its invaded range. Mass spectrometry proteomic methods were used to compare the microbial communities in wasp populations in the native (Belgium and England and invaded range (Argentina and New Zealand. We found no evidence of enemy release, as the number of microbial taxa was similar in both the introduced and native range. However, some evidence of distinctiveness in the microbial communities was observed between countries. The pathogens observed were similar to a variety of taxa observed in honey bees. These taxa included Nosema, Paenibacillus, and Yersina spp. Genomic methods confirmed a diversity of Nosema spp., Actinobacteria, and the Deformed wing and Kashmir bee viruses. We also analysed published records of bacteria, viruses, nematodes and fungi from both V. vulgaris and the related invader V. germanica. Thirty-three different microorganism taxa have been associated with wasps including Kashmir bee virus and entomophagous fungi such as Aspergillus flavus. There was no evidence that the presence or absence of these microorganisms was dependent on region of wasp samples (i.e. their native or invaded range. Given the similarity of the wasp pathogen fauna to that from honey bees, the lack of enemy release in wasp populations is probably related to spill-over or spill-back from bees and other social insects. Social insects appear to form a reservoir of generalist parasites and pathogens, which makes the management of wasp and bee disease difficult.

  20. No evidence of enemy release in pathogen and microbial communities of common wasps (Vespula vulgaris) in their native and introduced range.

    Science.gov (United States)

    Lester, Philip J; Bosch, Peter J; Gruber, Monica A M; Kapp, Eugene A; Peng, Lifeng; Brenton-Rule, Evan C; Buchanan, Joe; Stanislawek, Wlodek L; Archer, Michael; Corley, Juan C; Masciocchi, Maitè; Van Oystaeyen, Annette; Wenseleers, Tom

    2015-01-01

    When invasive species move to new environments they typically experience population bottlenecks that limit the probability that pathogens and parasites are also moved. The invasive species may thus be released from biotic interactions that can be a major source of density-dependent mortality, referred to as enemy release. We examined for evidence of enemy release in populations of the common wasp (Vespula vulgaris), which attains high densities and represents a major threat to biodiversity in its invaded range. Mass spectrometry proteomic methods were used to compare the microbial communities in wasp populations in the native (Belgium and England) and invaded range (Argentina and New Zealand). We found no evidence of enemy release, as the number of microbial taxa was similar in both the introduced and native range. However, some evidence of distinctiveness in the microbial communities was observed between countries. The pathogens observed were similar to a variety of taxa observed in honey bees. These taxa included Nosema, Paenibacillus, and Yersina spp. Genomic methods confirmed a diversity of Nosema spp., Actinobacteria, and the Deformed wing and Kashmir bee viruses. We also analysed published records of bacteria, viruses, nematodes and fungi from both V. vulgaris and the related invader V. germanica. Thirty-three different microorganism taxa have been associated with wasps including Kashmir bee virus and entomophagous fungi such as Aspergillus flavus. There was no evidence that the presence or absence of these microorganisms was dependent on region of wasp samples (i.e. their native or invaded range). Given the similarity of the wasp pathogen fauna to that from honey bees, the lack of enemy release in wasp populations is probably related to spill-over or spill-back from bees and other social insects. Social insects appear to form a reservoir of generalist parasites and pathogens, which makes the management of wasp and bee disease difficult.

  1. Arabidopsis thaliana: A model host plant to study plant-pathogen interaction using Chilean field isolates of Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    JUAN GONZÁLEZ

    2006-01-01

    Full Text Available One of the fungal pathogens that causes more agriculture damage is Botrytis cinerea. Botrytis is a constant threat to crops because the fungus infects a wide range of host species, both native and cultivated. Furthermore, Botrytis persists on plant debris in and on the soil. Some of the most serious diseases caused by Botrytis include gray mold on vegetables and fruits, such as grapes and strawberries. Botrytis also causes secondary soft rot of fruits and vegetables during storage, transit and at the market. In many plant-pathogen interactions, resistance often is associated with the deposition of callose, accumulation of autofluorescent compounds, the synthesis and accumulation of salicylic acid as well as pathogenesis-related proteins. Arabidopsis thaliana has been used as a plant model to study plant-pathogen interaction. The genome of Arabidopsis has been completely sequenced and this plant serves as a good genetic and molecular model. In this study, we demonstrate that Chilean field isolates infect Arabidopsis thaliana and that Arabidopsis subsequently activates several defense response mechanisms associated with a hypersensitive response. Furthermore, we propose that Arabidopsis may be used as a model host species to analyze the diversity associated with infectivity among populations of Botrytis cinerea field isolates

  2. Shewanella loihica sp. nov., isolated from iron-rich microbial mats in the Pacific Ocean.

    Science.gov (United States)

    Gao, Haichun; Obraztova, Anna; Stewart, Nathan; Popa, Radu; Fredrickson, James K; Tiedje, James M; Nealson, Kenneth H; Zhou, Jizhong

    2006-08-01

    A novel marine bacterial strain, PV-4(T), isolated from a microbial mat located at a hydrothermal vent of Loihi Seamount in the Pacific Ocean, has been characterized. This micro-organism is orangey in colour, Gram-negative, polarly flagellated, facultatively anaerobic and psychrotolerant (temperature range, 0-42 degrees C). No growth was observed with nitrate, nitrite, DMSO or thiosulfate as the electron acceptor and lactate as the electron donor. The major fatty acid detected in strain PV-4(T) was iso-C(15 : 0). Strain PV-4(T) had ubiquinones consisting mainly of Q-7 and Q-8, and possessed menaquinone MK-7. The DNA G+C content of the strain was 53.8 mol% and the genome size was about 4.5 Mbp. Phylogenetic analyses based on 16S rRNA gene sequences placed PV-4(T) within the genus Shewanella. PV-4(T) exhibited 16S rRNA gene sequence similarity levels of 99.6 and 97.5 %, respectively, with respect to the type strains of Shewanella aquimarina and Shewanella marisflavi. DNA from strain PV-4(T) showed low mean levels of relatedness to the DNAs of S. aquimarina (50.5 %) and S. marisflavi (8.5 %). On the basis of phylogenetic and phenotypic characteristics, the bacterium was classified in the genus Shewanella within a distinct novel species, for which the name Shewanella loihica sp. nov. is proposed. The type strain is PV-4(T) (=ATCC BAA-1088(T)=DSM 17748(T)).

  3. Ideonella sakaiensis sp. nov., isolated from a microbial consortium that degrades poly(ethylene terephthalate).

    Science.gov (United States)

    Tanasupawat, Somboon; Takehana, Toshihiko; Yoshida, Shosuke; Hiraga, Kazumi; Oda, Kohei

    2016-08-01

    A Gram-stain-negative, aerobic, non-spore-forming, rod-shaped bacterium, designed strain 201-F6T, was isolated from a microbial consortium that degrades poly(ethylene terephthalate) (PET) collected in Sakai city, Japan, and was characterized on the basis of a polyphasic taxonomic study. The cells were motile with a polar flagellum. The strain contained cytochrome oxidase and catalase. It grew within the pH range 5.5-9.0 (optimally at pH 7-7.5) and at 15-42 ºC (optimally at 30-37 ºC). The major isoprenoid quinone was ubiquinone with eight isoprene units (Q-8). C16 : 0, C17 : 0 cyclo, C18 :1ω7c and C12 : 0 2-OH were the predominant cellular fatty acids. The major polar lipids were phosphatidylethanolamine, lyso-phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The G+C content of genomic DNA was 70.4 mol%. Phylogenetic analysis using the 16S rRNA gene sequences showed that strain 201-F6T was affiliated to the genus Ideonella, and was closely related to Ideonella dechloratans LMG 28178T (97.7 %) and Ideonella azotifigens JCM 15503T (96.6 %). Strain 201-F6T could be clearly distinguished from the related species of the genus Ideonella by its physiological and biochemical characteristics as well as by its phylogenetic position and DNA-DNA relatedness. Therefore, the strain represents a novel species of the genus Ideonella, for which the name Ideonella sakaiensis sp. nov. (type strain 201-F6T=NBRC 110686T=TISTR 2288T) is proposed.

  4. Microbial gas generation under expected Waste Isolation Pilot Plant repository conditions

    International Nuclear Information System (INIS)

    Francis, A.J.; Gillow, J.B.; Giles, M.R.

    1997-03-01

    Gas generation from the microbial degradation of the organic constituents of transuranic waste under conditions expected at the Waste Isolation Pilot Plant (WIPP) repository was investigated at Brookhaven National Laboratory. The biodegradation of mixed cellulosics (various types of paper) and electron-beam irradiated plastic and rubber materials (polyethylene, polyvinylchloride, neoprene, hypalon, and leaded hypalon) was examined. The rate of gas production from cellulose biodegradation in inundated samples incubated for 1,228 days at 30 C was biphasic, with an initial rapid rate up to approximately 600 days incubation, followed by a slower rate. The rate of total gas production in anaerobic samples containing mixed inoculum was as follows: 0.002 mL/g cellulose/day without nutrients; 0.004 mL/g cellulose/day with nutrients; and 0.01 mL/g cellulose/day in the presence of excess nitrate. Carbon dioxide production proceeded at a rate of 0.009 micromol/g cellulose/day in anaerobic samples without nutrients, 0.05 micromol/g cellulose/day in the presence of nutrients, and 0.2 micromol/g cellulose/day with excess nitrate. Adding nutrients and excess nitrate stimulated denitrification, as evidenced by the accumulation of N 2 O in the headspace (200 micromol/g cellulose). The addition of the potential backfill bentonite increased the rate of CO 2 production to 0.3 micromol/g cellulose/day in anaerobic samples with excess nitrate. Analysis of the solution showed that lactic, acetic, propionic, butyric, and valeric acids were produced due to cellulose degradation. Samples incubated under anaerobic humid conditions for 415 days produced CO 2 at a rate of 0.2 micromol/g cellulose/day in the absence of nutrients, and 1 micromol/g cellulose/day in the presence of bentonite and nutrients. There was no evidence of biodegradation of electron-beam irradiated plastic and rubber

  5. Geographic isolates of Lymantria dispar multiple nucleopolyhedrovirus: Genome sequence analysis and pathogenicity against European and Asian gypsy moth strains.

    Science.gov (United States)

    Harrison, Robert L; Rowley, Daniel L; Keena, Melody A

    2016-06-01

    Isolates of the baculovirus species Lymantria dispar multiple nucleopolyhedrovirus have been formulated and applied to suppress outbreaks of the gypsy moth, L. dispar. To evaluate the genetic diversity in this species at the genomic level, the genomes of three isolates from Massachusetts, USA (LdMNPV-Ab-a624), Spain (LdMNPV-3054), and Japan (LdMNPV-3041) were sequenced and compared with four previously determined LdMNPV genome sequences. The LdMNPV genome sequences were collinear and contained the same homologous repeats (hrs) and clusters of baculovirus repeat orf (bro) gene family members in the same relative positions in their genomes, although sequence identities in these regions were low. Of 146 non-bro ORFs annotated in the genome of the representative isolate LdMNPV 5-6, 135 ORFs were found in every other LdMNPV genome, including the 37 core genes of Baculoviridae and other genes conserved in genus Alphabaculovirus. Phylogenetic inference with an alignment of the core gene nucleotide sequences grouped isolates 3041 (Japan) and 2161 (Korea) separately from a cluster containing isolates from Europe, North America, and Russia. To examine phenotypic diversity, bioassays were carried out with a selection of isolates against neonate larvae from three European gypsy moth (Lymantria dispar dispar) and three Asian gypsy moth (Lymantria dispar asiatica and Lymantria dispar japonica) colonies. LdMNPV isolates 2161 (Korea), 3029 (Russia), and 3041 (Japan) exhibited a greater degree of pathogenicity against all L. dispar strains than LdMNPV from a sample of Gypchek. This study provides additional information on the genetic diversity of LdMNPV isolates and their activity against the Asian gypsy moth, a potential invasive pest of North American trees and forests. Published by Elsevier Inc.

  6. Short communication: effect of exopolysaccharide isolated from "viili" on the adhesion of probiotics and pathogens to intestinal mucus.

    Science.gov (United States)

    Ruas-Madiedo, P; Gueimonde, M; de los Reyes-Gavilán, C G; Salminen, S

    2006-07-01

    The strong ropy character of the Scandinavian fermented milk viili is conferred by the exopolysaccharides (EPS) produced by lactococcal strains. These biopolymers can be responsible for some health benefits. We have assessed the influence of the EPS fraction isolated from commercial viili on the adhesion of some probiotics and pathogens to human intestinal mucus. Concentrations of viili EPS greater than 0.1 mg/mL promoted a decrease in adherence of Bifidobacterium lactis Bb12 and Lactobacillus rhamnosus GG and this effect was dose-dependent. However, no modifications were detected on the adhesion levels of the pathogenic strains tested at a concentration of 1 mg/mL of EPS. Results obtained in the present work should be considered in the design of new probiotic products.

  7. Biological activity of some bacterial isolates against soil borne pathogenic fungi

    International Nuclear Information System (INIS)

    Makbol, H.; Refae, R.I.; Eid, H.A.; Mohamed, O.M.

    2011-01-01

    The antagonistic activity of three bacterial isolates namely Micro bacterium terregens, Cellulosimicrobium cellulans and Bacillus amyloliquefaciens was evaluated through direct confrontation method and filtrates culture against the growth of Fusarium solani, Fusarium oxysporum, Rhizoctonia solani and Phytophthra cactorum. All bacterial isolates showed the inhibition of the mycelia growth of the isolated fungi as resulting to confrontation methods except R. solani with C. cellulans that showed no inhibitory effect and energized the low activity with B. amyloliquefaciens. Culture filtrate of different bacterial isolates after different incubation periods revealed that the highest antifungal activity between 3-10 days

  8. Use of static Quantitative Microbial Risk Assessment to determine pathogen risks in an unconfined carbonate aquifer used for Managed Aquifer Recharge.

    Science.gov (United States)

    Toze, Simon; Bekele, Elise; Page, Declan; Sidhu, Jatinder; Shackleton, Mark

    2010-02-01

    Managed Aquifer Recharge (MAR) is becoming a mechanism used for recycling treated wastewater and captured urban stormwater and is being used as a treatment barrier to remove contaminants such as pathogens from the recharged water. There is still a need, however, to demonstrate the effectiveness of MAR to reduce any residual risk of pathogens in the recovered water. A MAR research site recharging secondary treated wastewater in an unconfined carbonate aquifer was used in conjunction with a static Quantitative Microbial Risk Assessment (QMRA) to assess the microbial pathogen risk in the recovered water following infiltration and aquifer passage. The research involved undertaking a detailed hydrogeological assessment of the aquifer at the MAR site and determining the decay rates of reference pathogens from an in-situ decay study. These variables along with literature data were then used in the static QMRA which demonstrated that the recovered water at this site did not meet the Australian Guidelines for recycled water when used for differing private green space irrigation scenarios. The results also confirmed the importance of obtaining local hydrogeological data as local heterogeneity can influence of residence time in the aquifer which, in turn, influences the outcomes. The research demonstrated that a static QMRA can be used to determine the residual risk from pathogens in recovered water and showed that it can be a valuable tool in the preliminary design and operation of MAR systems and the incorporation of complementary engineered treatment processes to ensure that there is acceptable health risk from the recovered water. Crown Copyright 2009. Published by Elsevier Ltd. All rights reserved.

  9. Comparison of pathogen DNA isolation methods from large volumes of whole blood to improve molecular diagnosis of bloodstream infections.

    Directory of Open Access Journals (Sweden)

    Anne J M Loonen

    Full Text Available For patients suffering from bloodstream infections (BSI molecular diagnostics from whole blood holds promise to provide fast and adequate treatment. However, this approach is hampered by the need of large blood volumes. Three methods for pathogen DNA isolation from whole blood were compared, i.e. an enzymatic method (MolYsis, 1-5 ml, the novel non-enzymatic procedure (Polaris, 1-5 ml, and a method that does not entail removal of human DNA (Triton-Tris-EDTA EasyMAG, 200 µl. These methods were evaluated by processing blood spiked with 0-1000 CFU/ml of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. Downstream detection was performed with real-time PCR assays. Polaris and MolYsis processing followed by real-time PCRs enabled pathogen detection at clinically relevant concentrations of 1-10 CFU/ml blood. By increasing sample volumes, concurrent lower cycle threshold (Ct values were obtained at clinically relevant pathogen concentrations, demonstrating the benefit of using larger blood volumes. A 100% detection rate at a concentration of 10 CFU/ml for all tested pathogens was obtained with the Polaris enrichment, whereas comparatively lower detection rates were measured for MolYsis (50-67% and EasyMAG (58-79%. For the samples with a concentration of 1 CFU/ml Polaris resulted in most optimal detection rates of 70-75% (MolYsis 17-50% and TTE-EasyMAG 20-36%. The Polaris method was more reproducible, less labour intensive, and faster (45 minutes (including Qiagen DNA extraction vs. 2 hours (MolYsis. In conclusion, Polaris and MolYsis enrichment followed by DNA isolation and real-time PCR enables reliable and sensitive detection of bacteria and fungi from 5 ml blood. With Polaris results are available within 3 hours, showing potential for improved BSI diagnostics.

  10. Current Microbial Isolates from Wound Swab and Their Susceptibility Pattern in a Private Medical College Hospital in Dhaka city

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    Shahin Sultana

    2015-03-01

    Full Text Available Background: Wound infection is one of the major health problems that are caused and aggravated by the invasion of pathogenic organisms where empiric treatment is routine. Objective: To isolate and identify the bacteria causing wound infection and to determine the antimicrobial susceptibility pattern. Materials and method: A total of 263 wound swab and pus samples were collected during the period of January to December 2012 from Delta Medical College and Hospital, Dhaka, Bangladesh. Swabs from the wound were inoculated on appropriate media and cultured and the isolates were identified by standard procedures as needed. Antimicrobial susceptibility testing was performed by disk diffusion method according to ‘The Clinical Laboratory Standard Institute’ guidelines. Results: In this study 220 bacterial isolates were recovered from 263 samples showing an isolation rate of 83.65%. The predominant bacteria isolated from infected wounds were Staphylococcus aureus 89 (40.45% followed by Escherichia coli 62 (28.18%, Pseudomonas aeruginosa 34 (15.45%, Enterococci 18 (8.18%, Acinetobacter 5 (2.27%, Klebsiella 9 (4.09% and Proteus 3 (3.36%. Staphylococcus aureus was sensitive to linezolid (94.38%, fusidic acid (91.01%, vancomycin (87.64%, amikacin (74.15% and gentamicin (73.03%. Among the Gram negative isolates Escherichia coli was predominant and showed sensitivity to imipenem (93.54% amikacin (83.87% colistin (53.22% and piperacillin and tazobactum (53.22% and pseudomonas showed sensitivity to amikacin (73.52%, imipenem (70.58% and colistin (70.58%. Conclusion: Staphylococcus aureus was the most frequently isolated pathogen from wound swab and the antibiotic sensitivity pattern of various isolates help to assist the clinician in appropriate selection of empirical antibiotics against wound infection.

  11. Widespread distribution of a tet W determinant among tetracycline-resistant isolates of the animal pathogen Arcanobacterium pyogenes.

    Science.gov (United States)

    Billington, Stephen J; Songer, J Glenn; Jost, B Helen

    2002-05-01

    Tetracycline resistance is common among isolates of the animal commensal and opportunistic pathogen Arcanobacterium pyogenes. The tetracycline resistance determinant cloned from two bovine isolates of A. pyogenes was highly similar at the DNA level (92% identity) to the tet(W) gene, encoding a ribosomal protection tetracycline resistance protein, from the rumen bacterium Butyrivibrio fibrisolvens. The tet(W) gene was found in all 20 tetracycline-resistant isolates tested, indicating that it is a widely distributed determinant of tetracycline resistance in this organism. In 25% of tetracycline-resistant isolates, the tet(W) gene was associated with a mob gene, encoding a functional mobilization protein, and an origin of transfer, suggesting that the determinant may be transferable to other bacteria. In fact, low-frequency transfer of tet(W) was detected from mob+ A. pyogenes isolates to a tetracycline-sensitive A. pyogenes recipient. The mobile nature of this determinant and the presence of A. pyogenes in the gastrointestinal tract of cattle and pigs suggest that A. pyogenes may have inherited this determinant within the gastrointestinal tracts of these animals.

  12. Pathogenic potentials of Aeromonas species isolated from aquaculture and abattoir environments.

    Science.gov (United States)

    Igbinosa, Isoken H; Beshiru, Abeni; Odjadjare, Emmanuel E; Ateba, Collins N; Igbinosa, Etinosa O

    2017-06-01

    The present study elucidated the presence of antibiotics resistance, virulence genes and biofilm potentials among Aeromonas species isolated from abattoir and aquaculture environments in Benin City, Nigeria. A total of 144 wastewater samples were obtained from two independent aquaculture and abattoir environments between May and October 2016. Aeromonas species were isolated on Glutamate Starch Phenol Red (GSP) agar and confirmed using API 20NE kits. Antimicrobial susceptibility profile of the isolates was carried out using standard disc diffusion assay while biofilm potentials were detected by the microtitre plate method and PCR technique was used to detect antibiotics resistance and virulence gene markers. Overall, 32 and 26 Aeromonas species were isolated from the abattoir and aquaculture environments respectively. Isolates from both environments were completely resistant (100%) to penicillin G, ertapenem and tetracycline; whereas aquaculture isolates exhibited absolute sensitivity (100%) towards cefepime. All the virulence gene markers (aerA, hlyA, alt, ast, laf, ascF-G, fla, lip, stx1, and stx2) investigated in this study (except laf) were detected in isolates from both environments. The laf genes were only detected in isolates from abattoir environments. Antibiotics resistant genes including pse, bla TEM and class 1 integron were detected in isolates from both environments. Majority of the isolates (53/58 91.4%) from both environments; demonstrated capacity for biofilm potential. The detection of antibiotic resistance and virulence gene markers as well as biofilm forming ability in Aeromonas species isolated from aquaculture and abattoir environments raise serious public health concern worthy of further investigation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. pirABvp-Bearing Vibrio parahaemolyticus and Vibrio campbellii Pathogens Isolated from the Same AHPND-Affected Pond Possess Highly Similar Pathogenic Plasmids

    Directory of Open Access Journals (Sweden)

    Xuan Dong

    2017-10-01

    Full Text Available Acute hepatopancreatic necrosis disease (AHPND is a severe shrimp disease originally shown to be caused by virulent strains of Vibrio parahaemolyticus (VPAHPND. Rare cases of AHPND caused by Vibrio species other than V. parahaemolyticus were reported. We compared an AHPND-causing V. campbellii (VCAHPND and a VPAHPND isolate from the same AHPND-affected pond. Both strains are positive for the virulence genes pirABvp. Immersion challenge test with Litopenaeus vannamei indicated the two strains possessed similar pathogenicity. Complete genome comparison showed that the pirABvp-bearing plasmids in the two strains were highly homologous, and they both shared high homologies with plasmid pVA1, the reported pirABvp-bearing plasmid. Conjugation and DNA-uptake genes were found on the pVA1-type plasmids and the host chromosomes, respectively, which may facilitate the dissemination of pirABvp. Novel variations likely driven by ISVal1 in the genetic contexts of the pirABvp genes were found in the two strains. Moreover, the VCAHPND isolate additionally contains multiple antibiotic resistance genes, which may bring difficulties to control its future outbreak. The dissemination of the pirABvp in non-parahaemolyticus Vibrio also rises the concern of missing detection in industrial settings since the isolation method currently used mainly targeting V. parahaemolyticus. This study provides timely information for better understanding of the causes of AHPND and molecular epidemiology of pirABvp and also appeals for precautions to encounter the dissemination of the hazardous genes.

  14. Draft Genome Sequences of 17 Isolates of the Plant Pathogenic Bacterium Dickeya

    OpenAIRE

    Pritchard, Leighton; Humphris, Sonia; Saddler, Gerry S.; Elphinstone, John G.; Pirhonen, Minna; Toth, Ian K.

    2013-01-01

    Dickeya (formerly Erwinia chrysanthemi) species cause diseases on a wide range of crops and ornamental plants worldwide. Here we present the draft sequences of 17 Dickeya isolates spanning four Dickeya species, including five isolates that are currently unassigned to a species.

  15. Draft genome sequences of 17 isolates of the plant pathogenic bacterium dickeya.

    Science.gov (United States)

    Pritchard, Leighton; Humphris, Sonia; Saddler, Gerry S; Elphinstone, John G; Pirhonen, Minna; Toth, Ian K

    2013-11-21

    Dickeya (formerly Erwinia chrysanthemi) species cause diseases on a wide range of crops and ornamental plants worldwide. Here we present the draft sequences of 17 Dickeya isolates spanning four Dickeya species, including five isolates that are currently unassigned to a species.

  16. [The in vitro antifungal activities of fluconazole against pathogenic yeasts recently isolated from clinical specimens].

    Science.gov (United States)

    Yamaguchi, H; Igari, J; Kume, H; Abe, M; Oguri, T; Kanno, H; Kawakami, S; Okuzumi, K; Fukayama, M; Ito, A; Kawata, K; Uchida, K

    1997-09-01

    The emergence of Candida albicans resistance to azole antifungal agents have been reported in the U. S. and Europe. We examined the in vitro antifungal activities of fluconazole against clinical isolates collected by seven investigators in three years to examine if a tendency existed toward the development of azole-resistance among fungal isolates in Japan. The following results were obtained: 1. Sensitivities to fluconazole (FLCZ) were determined for yeast-like fungi, including 113 strains isolated in 1993, 149 strains isolated in 1994 and 205 strains isolated in 1995. No significant differences in sensitivities in the three years were detected. 2. Minimum inhibitory concentrations of FLCZ were 0.1-0.78 microgram/ml for C. albicans and 3.13-25 micrograms/ml for C. glabrata. Strains with 25 micrograms/ml of FLCZ's MIC were detected; two strains of C. krusei and one strain each of C. krusei, Trichospron beigelii and Hansenula anomala. No strains with higher than 50 micrograms/ml MIC of FLCZ were detected. 3. In vitro activities of FLCZ were compared between clinical strains isolated between 1993 and 1995 and clinical strains isolated before the marketing of FLCZ (up to December 1987) or clinical yeasts isolated between 1991 and 1992. No significant differences were observed, suggesting that no tendency existed toward azole resistance among fungal strains examined.

  17. Characterization of field isolates of Magnaporthe oryzae with mating type, DNA fingerprinting, and pathogenicity assays

    Science.gov (United States)

    Due to the harmful nature of the rice blast fungus, Magnaporthe oryzae, it is beneficial to characterize field isolates to help aid in the deployment of resistance (R) genes in rice. In the present study, 190 field isolates of M. oryzae, collected from rice fields of Yunnan province in China, were a...

  18. Draft genome of the emerging pathogen, Kocuria marina, isolated from a wild urban rat

    Directory of Open Access Journals (Sweden)

    Shih Keng Loong

    Full Text Available Kocuria marina has recently emerged as a cause for catheter-related bloodstream infections in patients with underlying health complications. One K. marina strain was recently isolated from the lung tissues of a wild urban rat (Rattus rattus diardii caught during rodent surveillance. Here, we present the draft genome of the first K. marina animal isolate, K. marina TRE150902.

  19. The isolation and partial characterization of a highly pathogenic herpesvirus from the harbor seal (Phoca vitulina).

    NARCIS (Netherlands)

    A.D.M.E. Osterhaus (Albert); H. Yang (Hong); H.E.M. Spijkers (Ine); J. Groen (Jan); J.S. Teppema; G. van Steenis (Bert)

    1985-01-01

    textabstractThis report describes the first isolation and partial characterization of a herpesvirus from the harbor seal (Phoca vitulina). The virus was isolated during a disease outbreak in a group of young seals nursed in a seal orphanage in The Netherlands. Almost half of the seals died with

  20. Pathogenic Escherichia coli producing Extended-Spectrum β-Lactamases isolated from surface water and wastewater.

    Science.gov (United States)

    Franz, Eelco; Veenman, Christiaan; van Hoek, Angela H A M; de Roda Husman, Ana; Blaak, Hetty

    2015-09-24

    To assess public health risks from environmental exposure to Extended-Spectrum β-Lactamases (ESBL)-producing bacteria, it is necessary to have insight in the proportion of relative harmless commensal variants and potentially pathogenic ones (which may directly cause disease). In the current study, 170 ESBL-producing E. coli from Dutch wastewater (n = 82) and surface water (n = 88) were characterized with respect to ESBL-genotype, phylogenetic group, resistance phenotype and virulence markers associated with enteroaggregative E. coli (EAEC), enteroinvasive E. coli (EIEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), extraintesinal E. coli (ExPEC), and Shiga toxin-producing E. coli (STEC). Overall, 17.1% of all ESBL-producing E. coli were suspected pathogenic variants. Suspected ExPECs constituted 8.8% of all ESBL-producing variants and 8.3% were potential gastrointestinal pathogens (4.1% EAEC, 1.8% EPEC, 1.2% EIEC, 1.2% ETEC, no STEC). Suspected pathogens were significantly associated with ESBL-genotype CTX-M-15 (X(2) = 14.7, P antibiotics. In conclusion, this study demonstrates that the aquatic environment is a potential reservoir of E. coli variants that combine ESBL-genes, a high level of multi-drug resistance and virulence factors, and therewith pose a health risk to humans upon exposure.

  1. Microbial quality and molecular identification of cultivable microorganisms isolated from an urban drinking water distribution system (Limassol, Cyprus).

    Science.gov (United States)

    Botsaris, George; Kanetis, Loukas; Slaný, Michal; Parpouna, Christiana; Makris, Konstantinos C

    2015-12-01

    Microorganisms can survive and multiply in aged urban drinking water distribution systems, leading to potential health risks. The objective of this work was to investigate the microbial quality of tap water and molecularly identify its predominant cultivable microorganisms. Tap water samples collected from 24 different households scattered in the urban area of Limassol, Cyprus, were microbiologically tested following standard protocols for coliforms, E. coli, Pseudomonas spp., Enterococcus spp., and total viable count at 22 and 37 °C. Molecular identification was performed on isolated predominant single colonies using 16SrRNA sequencing. Approximately 85% of the household water samples were contaminated with one or more microorganisms belonging to the genera of Pseudomonas, Corynebacterium, Agrobacterium, Staphylococcus, Bacillus, Delftia, Acinetobacter, Enterococcus, Enterobacter, and Aeromonas. However, all samples tested were free from E. coli. This is the first report in Cyprus molecularly confirming specific genera of relevant microbial communities in tap water.

  2. Isolation of pathogenic yeasts in the air from hospital environments in the city of Fortaleza, northeast Brazil

    Directory of Open Access Journals (Sweden)

    Rossana A Cordeiro

    Full Text Available This paper reports the results of environmental surveillance of yeasts in specific areas of two tertiary local hospitals. From March 2007 to February 2008, samples from the air of two public hospitals were collected on a monthly basis. The samples were collected through passive sedimentation method (day and night exposure of Petri dishes. A total of 240 air samples from 10 hospital environments were analyzed. These environments presented similar contamination levels, from which 80 fungi isolates were isolated: Candida parapsilosis (n = 34, Rhodotorula spp. (19, Trichosporon asahii (11, C. tropicalis (8, C. albicans (4, C. glabrata (1, C. guilliermondii (1, C. krusei (1 and Saccharomyces spp. (1. Regarding the presence of yeasts and climatic conditions, there were 40 strains (50% in semi-critical areas (natural ventilation and critical areas (air conditioned. Considering the presence of microorganisms with pathogenic potential, environmental monitoring is necessary to prevent possible hospital infections.

  3. Microbial gas generation under expected Waste Isolation Pilot Plant repository conditions

    Energy Technology Data Exchange (ETDEWEB)

    Francis, A.J.; Gillow, J.B.; Giles, M.R. [Brookhaven National Lab., Upton, NY (United States). Dept. of Applied Science

    1997-03-01

    Gas generation from the microbial degradation of the organic constituents of transuranic waste under conditions expected at the Waste Isolation Pilot Plant (WIPP) repository was investigated at Brookhaven National Laboratory. The biodegradation of mixed cellulosics (various types of paper) and electron-beam irradiated plastic and rubber materials (polyethylene, polyvinylchloride, neoprene, hypalon, and leaded hypalon) was examined. The rate of gas production from cellulose biodegradation in inundated samples incubated for 1,228 days at 30 C was biphasic, with an initial rapid rate up to approximately 600 days incubation, followed by a slower rate. The rate of total gas production in anaerobic samples containing mixed inoculum was as follows: 0.002 mL/g cellulose/day without nutrients; 0.004 mL/g cellulose/day with nutrients; and 0.01 mL/g cellulose/day in the presence of excess nitrate. Carbon dioxide production proceeded at a rate of 0.009 {micro}mol/g cellulose/day in anaerobic samples without nutrients, 0.05 {micro}mol/g cellulose/day in the presence of nutrients, and 0.2 {micro}mol/g cellulose/day with excess nitrate. Adding nutrients and excess nitrate stimulated denitrification, as evidenced by the accumulation of N{sub 2}O in the headspace (200 {micro}mol/g cellulose). The addition of the potential backfill bentonite increased the rate of CO{sub 2} production to 0.3 {micro}mol/g cellulose/day in anaerobic samples with excess nitrate. Analysis of the solution showed that lactic, acetic, propionic, butyric, and valeric acids were produced due to cellulose degradation. Samples incubated under anaerobic humid conditions for 415 days produced CO{sub 2} at a rate of 0.2 {micro}mol/g cellulose/day in the absence of nutrients, and 1 {micro}mol/g cellulose/day in the presence of bentonite and nutrients. There was no evidence of biodegradation of electron-beam irradiated plastic and rubber.

  4. Antagonistic activities of some Bifidobacterium sp. strains isolated from resident infant gastrointestinal microbiota on Gram-negative enteric pathogens.

    Science.gov (United States)

    Delcaru, Cristina; Alexandru, Ionela; Podgoreanu, Paulina; Cristea, Violeta Corina; Bleotu, Coralia; Chifiriuc, Mariana Carmen; Bezirtzoglou, Eugenia; Lazar, Veronica

    2016-06-01

    The gastrointestinal microbiota contributes to the consolidation of the anti-infectious barrier against enteric pathogens. The purpose of this study was to investigate the influence of Bifidobacterium sp. strains, recently isolated from infant gastrointestinal microbiota on the in vitro growth and virulence features expression of enteropathogenic bacterial strains. The antibacterial activity of twelve Bifidobacterium sp. strains isolated from human feces was examined in vitro against a wide range of Gram negative pathogenic strains isolated from 30 infant patients (3 days to 5 years old) with diarrhea. Both potential probiotic strains (Bifidobacterium longum, Bifidobacterium pseudocatenulatum, Bifidobacterium catenulatum, Bifidobacterium breve, Bifidobacterium ruminantium) and enteropathogenic strains (EPEC, EIEC, Klebsiella pneumoniae, Salmonella sp., Yersinia enterocolitica, Pseudomonas aeruginosa) were identified by MALDI-TOF and confirmed serologically when needed. The bactericidal activity, growth curve, adherence to the cellular HEp-2 substratum and production of soluble virulence factors have been assessed in the presence of different Bifidobacterium sp. cultures and fractions (whole culture and free-cell supernatants). Among the twelve Bifidobacterium sp. strains, the largest spectrum of antimicrobial activity against 9 of the 18 enteropathogenic strains was revealed for a B. breve strain recently isolated from infant intestinal feces. The whole culture and free-cell supernatant of B. breve culture decreased the multiplication rate, shortened the log phase and the total duration of the growth curve, with an earlier entrance in the decline phase and inhibited the adherence capacity to a cellular substratum and the swimming/swarming motility too. These results indicate the significant probiotic potential of the B. breve strain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Assessment of Shiga toxin-producing Escherichia coli isolates from wildlife meat as potential pathogens for humans.

    Science.gov (United States)

    Miko, Angelika; Pries, Karin; Haby, Sabine; Steege, Katja; Albrecht, Nadine; Krause, Gladys; Beutin, Lothar

    2009-10-01

    A total of 140 Shiga toxin-producing Escherichia coli (STEC) strains from wildlife meat (deer, wild boar, and hare) isolated in Germany between 1998 and 2006 were characterized with respect to their serotypes and virulence markers associated with human pathogenicity. The strains grouped into 38 serotypes, but eight O groups (21, 146, 128, 113, 22, 88, 6, and 91) and four H types (21, 28, 2, and 8) accounted for 71.4% and 75.7% of all STEC strains from game, respectively. Eighteen of the serotypes, including enterohemorrhagic E. coli (EHEC) O26:[H11] and O103:H2, were previously found to be associated with human illness. Genes linked to high-level virulence for humans (stx(2), stx(2d), and eae) were present in 46 (32.8%) STEC strains from game. Fifty-four STEC isolates from game belonged to serotypes which are frequently found in human patients (O103:H2, O26:H11, O113:H21, O91:H21, O128:H2, O146:H21, and O146:H28). These 54 STEC isolates were compared with 101 STEC isolates belonging to the same serotypes isolated from farm animals, from their food products, and from human patients. Within a given serotype, most STEC strains were similar with respect to their stx genotypes and other virulence attributes, regardless of origin. The 155 STEC strains were analyzed for genetic similarity by XbaI pulsed-field gel electrophoresis. O103:H2, O26:H11, O113:H21, O128:H2, and O146:H28 STEC isolates from game were 85 to 100% similar to STEC isolates of the same strains from human patients. By multilocus sequence typing, game EHEC O103:H2 strains were attributed to a clonal lineage associated with hemorrhagic diseases in humans. The results from our study indicate that game animals represent a reservoir for and a potential source of human pathogenic STEC and EHEC strains.

  6. Assessment of Shiga Toxin-Producing Escherichia coli Isolates from Wildlife Meat as Potential Pathogens for Humans▿

    Science.gov (United States)

    Miko, Angelika; Pries, Karin; Haby, Sabine; Steege, Katja; Albrecht, Nadine; Krause, Gladys; Beutin, Lothar

    2009-01-01

    A total of 140 Shiga toxin-producing Escherichia coli (STEC) strains from wildlife meat (deer, wild boar, and hare) isolated in Germany between 1998 and 2006 were characterized with respect to their serotypes and virulence markers associated with human pathogenicity. The strains grouped into 38 serotypes, but eight O groups (21, 146, 128, 113, 22, 88, 6, and 91) and four H types (21, 28, 2, and 8) accounted for 71.4% and 75.7% of all STEC strains from game, respectively. Eighteen of the serotypes, including enterohemorrhagic E. coli (EHEC) O26:[H11] and O103:H2, were previously found to be associated with human illness. Genes linked to high-level virulence for humans (stx2, stx2d, and eae) were present in 46 (32.8%) STEC strains from game. Fifty-four STEC isolates from game belonged to serotypes which are frequently found in human patients (O103:H2, O26:H11, O113:H21, O91:H21, O128:H2, O146:H21, and O146:H28). These 54 STEC isolates were compared with 101 STEC isolates belonging to the same serotypes isolated from farm animals, from their food products, and from human patients. Within a given serotype, most STEC strains were similar with respect to their stx genotypes and other virulence attributes, regardless of origin. The 155 STEC strains were analyzed for genetic similarity by XbaI pulsed-field gel electrophoresis. O103:H2, O26:H11, O113:H21, O128:H2, and O146:H28 STEC isolates from game were 85 to 100% similar to STEC isolates of the same strains from human patients. By multilocus sequence typing, game EHEC O103:H2 strains were attributed to a clonal lineage associated with hemorrhagic diseases in humans. The results from our study indicate that game animals represent a reservoir for and a potential source of human pathogenic STEC and EHEC strains. PMID:19700552

  7. Frequency Of Isolation Of Salmonella From Commercial Poultry Feeds And Their Anti-Microbial Resistance Profiles, Imo State, Nigeria

    Directory of Open Access Journals (Sweden)

    Okoli IC

    2006-09-01

    Full Text Available This study was conducted to determine the frequency of isolation of salmonella and their microbial resistance profiles across different commercial poultry feeds sold in Imo State, Nigeria. Thirty-six bulk feed samples were colleted from 154 bag across different feed types and brands which included Guinea (GF, Top (TF, Vital (VF, Extra (EF, Animal care (AF and livestock (LF feeds. The salmonella isolated were tested against 14 anti-microbial drugs using the disc diffusion method. Bacterial load enumeration of the samples indicated a range of <30 colony forming unit (CFU to overgrowth at 104 serial dilutions. Eight feed samples (22.2% which cuts across the entire feed brands expect EF were positive for salmonella. The highest prevalence of 28.8% and 25.0% were recorded for LF and TF respectively, while VF, GF and AF had 11.1 and 10.0% respectively. Salmonella isolates showed high rates of resistance (51-100% against nitrofurantoin, ampicillin, tetracycline and ceftriazole, while moderate rates (31-50% were recorded for chloramphenicol, oxfloxacin and cotrimoxazole. Low resistance rates (1-30% were on the other hand recorded against ciprofloxacin and amoxycillin clavulanate (Augumentine, whereas zero resistance was demonstrated against pefloxacin, gentamycin, streptomycin and nalidixic. Commercial feeds form important channels for the dissemination of multi-drug resistant salmonella in Imo State, Nigeria.

  8. Field study on the epidemiology and pathogenicity of different isolates of bovine Ostertagia spp.

    Science.gov (United States)

    Al Saqur, I; Armour, J; Bairden, K; Dunn, A M; Jennings, F W; Murray, M

    1982-11-01

    The epidemiological features of three different isolates of bovine Ostertagia spp under similar initial levels of larval challenge were compared in the field. Two of the isolates, consisting mainly of Ostertagia ostertagi, and a low proportion of Skrjabinagia lyrata conformed in epidemiological behaviour with those investigated by previous workers, though the worm burdens which established did not give rise to the expected clinical signs. The third isolate behaved in a different way, yielding very high faecal egg counts which were followed by high pasture larval counts, heavy worm burdens and severe clinical disease. This isolate, while consisting mainly of O ostertagi and a few S lyrata, also contained a proportion of O leptospicularis, and it is suggested that this species may influence the dynamics of the host-parasite relationship in bovine ostertagiasis.

  9. Lysis of mastitis pathogens isolated from dairy cow milk samples by ...

    African Journals Online (AJOL)

    This recombinant lysostaphin was purified by a His60 Ni Gravity Column to obtain milligram amounts of recombinant lysostaphin protein with high purity. ... The antibiotic resistance of the isolates was determined by disc diffusion assay. Most of ...

  10. Molecular characterization, phylogeny analysis and pathogenicity of a Muscovy duck adenovirus strain isolated in China in 2014

    International Nuclear Information System (INIS)

    Zhang, Xinheng; Zhong, Yangjin; Zhou, Zhenhai; Liu, Yang; Zhang, Huanmin; Chen, Feng; Chen, Weiguo; Xie, Qingmei

    2016-01-01

    This study aimed to characterize a novel adenovirus (AdV) isolated from diseased Muscovy ducks in China. After the AdV was successfully propagated in duck embryo fibroblasts, the morphological and physicochemical properties of the virions were studied by electron microscopy and different tests. The results of the analyses were in conformity with AdV properties. The full genome sequence was determined and analyzed. The new isolate (named CH-GD-12-2014) shared over 91% sequence identity with duck AdV-2 representing the species Duck aviadenovirus B. The most important distinguishing feature between the two DAdV strains was the presence of a second fiber gene in the Chinese isolate. Phylogeny reconstruction confirmed the affiliation of the virus with goose and duck AdVs in the genus Aviadenovirus. Experimental infection resulted in embryo death, and intramuscular inoculation provoked morbidity and mortality among ducks and chickens. - Highlights: • A duck adenovirus type 3 was isolated and the complete genome of DAdV-3 was obtained. • Physicochemical properties and electron microscopy were researched. • Pathogenicity of duck adenovirus type 3 was researched.

  11. Antibacterial Activity of Lactic Acid Bacteria Isolated from Gastrointestinal Tract of “Ayam Kampung” Chicken Against Food Pathogens

    Science.gov (United States)

    Nur Jannah, Siti; Rini Saraswati, Tyas; Handayani, Dwi; Pujiyanto, Sri

    2018-05-01

    Food borne disease results from ingestion of water and wide variety of food contaminated with pathogenic organisms. The main causes of food borne diseases are bacteria, such as Escherichia coli and Staphylococcus aureus. The objective of this study was to determine antimicrobial activity of lactic acid bacteria (LAB) isolated from local chicken gastrointestinal tract with an emphasis on their probiotic properties. The colonies of bacteria that producing clear zone on MRSA plus 0.5% CaCO3, Gram-positive and catalase-negative were isolated as lactic acid bacteria. Some of the strains (10 isolates) were tested for their ability to inhibit growth of Escherichia coli and Staphylococcus aureus, and for acid pH and bile salt tolerance. The results showed that the all selected isolates producing antimicrobial compounds inhibits the growth of Escherichia coli and Staphylococcus aureus, both in the supernatant and supernatant plus 2M NaOH, and still growing in medium condition with pH 2.0 and 0.1% bile salt. It revealing the potential use of the lactic acid bacteria from chicken gastrointestinal tract for probiotics in food.

  12. Molecular characterization, phylogeny analysis and pathogenicity of a Muscovy duck adenovirus strain isolated in China in 2014

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xinheng [College of Animal Science, South China Agricultural University & Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Guangzhou 510642 (China); Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou, Guangdong 510642 (China); South China Collaborative Innovation Center for Poultry Disease Control and Product Safety, Guangzhou 510642 (China); Zhong, Yangjin; Zhou, Zhenhai; Liu, Yang [College of Animal Science, South China Agricultural University & Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Guangzhou 510642 (China); Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou, Guangdong 510642 (China); Zhang, Huanmin [USDA, Agriculture Research Service, Avian Disease and Oncology Laboratory, East Lansing, MI 48823 (United States); Chen, Feng [College of Animal Science, South China Agricultural University & Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Guangzhou 510642 (China); Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou, Guangdong 510642 (China); Chen, Weiguo [College of Animal Science, South China Agricultural University & Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Guangzhou 510642 (China); Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou, Guangdong 510642 (China); South China Collaborative Innovation Center for Poultry Disease Control and Product Safety, Guangzhou 510642 (China); Xie, Qingmei, E-mail: qmx@scau.edu.cn [College of Animal Science, South China Agricultural University & Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Guangzhou 510642 (China); Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou, Guangdong 510642 (China); South China Collaborative Innovation Center for Poultry Disease Control and Product Safety, Guangzhou 510642 (China)

    2016-06-15

    This study aimed to characterize a novel adenovirus (AdV) isolated from diseased Muscovy ducks in China. After the AdV was successfully propagated in duck embryo fibroblasts, the morphological and physicochemical properties of the virions were studied by electron microscopy and different tests. The results of the analyses were in conformity with AdV properties. The full genome sequence was determined and analyzed. The new isolate (named CH-GD-12-2014) shared over 91% sequence identity with duck AdV-2 representing the species Duck aviadenovirus B. The most important distinguishing feature between the two DAdV strains was the presence of a second fiber gene in the Chinese isolate. Phylogeny reconstruction confirmed the affiliation of the virus with goose and duck AdVs in the genus Aviadenovirus. Experimental infection resulted in embryo death, and intramuscular inoculation provoked morbidity and mortality among ducks and chickens. - Highlights: • A duck adenovirus type 3 was isolated and the complete genome of DAdV-3 was obtained. • Physicochemical properties and electron microscopy were researched. • Pathogenicity of duck adenovirus type 3 was researched.

  13. Salmonella infection in healthy pet reptiles: Bacteriological isolation and study of some pathogenic characters.

    Science.gov (United States)

    Bertelloni, Fabrizio; Chemaly, Marianne; Cerri, Domenico; Gall, Françoise Le; Ebani, Valentina Virginia

    2016-06-01

    The fecal samples from 213 captive reptiles were examined, and 29 (13.61%) Salmonella enterica isolates were detected: 14/62 (22.58%) from chelonians, 14/135 (10.37%) from saurians, and 1/16 (6.25%) from ophidians. The isolates were distributed among 14 different serotypes: Miami, Ebrie, Hermannsweder, Tiergarten, Tornov, Pomona, Poona, Goteborg, Abaetetube, Nyanza, Kumasi, Typhimurium, 50:b:z6, 9,12:z29:1,5, and a non-motile serotype with antigenic formula 1,4,[5],12:-:-. Salmonella typhimurium and 50:b:z6 isolates showed the spv plasmid virulence genes, responsible of the capability to induce extra-intestinal infections. In some cases, pulsed field gel electrophoresis revealed different profiles for the strains of the same serotypes, showing different origins, whereas a common source of infection was supposed when one pulsotype had been observed for isolates of a serovar. Twenty-seven (93.10%) isolates showed resistance to one or more antibiotics. Ceftazidime was active to all the tested isolates, whereas the highest percentages of strains were no susceptible to tigecycline (93.10%), streptomycin (89.66%), and sulfonamide (86.21%).

  14. Isolations from the redbay ambrosia beetle, Xyleborus glabratus, confirm that the laurel wilt pathogen, Raffaelea lauricola, originated in Asia.

    Science.gov (United States)

    Harrington, Thomas C; Yun, Hye Young; Lu, Sheng-Shan; Goto, Hideaki; Aghayeva, Dilzara N; Fraedrich, Stephen W

    2011-01-01

    The laurel wilt pathogen Raffaelea lauricola was hypothesized to have been introduced to the southeastern USA in the mycangium of the redbay ambrosia beetle, Xyleborus glabratus, which is native to Asia. To test this hypothesis adult X. glabratus were trapped in Taiwan and on Kyushu Island, Japan, in 2009, and dead beetles were sent to USA for isolation of fungal symbionts. Individual X. glabratus were macerated in glass tissue grinders, and the slurry was serially diluted and plated onto malt agar medium amended with cycloheximide, a medium semiselective for Ophiostoma species and their anamorphs, including members of Raffaelea. R. lauricola was isolated from 56 of 85 beetles in Taiwan and 10 of 16 beetles in Japan at up to an estimated 10 000 CFUs per beetle. The next most commonly isolated species was R. ellipticospora, which also has been recovered from X. glabratus trapped in the USA, as were two other fungi isolated from beetles in Taiwan, R. fusca and R. subfusca. Three unidentified Raffaelea spp. and three unidentified Ophiostoma spp. were isolated rarely from X. glabratus collected in Taiwan. Isolations from beetles similarly trapped in Georgia, USA, yielded R. lauricola and R. ellipticospora in numbers similar to those from beetles trapped in Taiwan and Japan. The results support the hypothesis that R. lauricola was introduced into the USA in mycangia of X. glabratus shipped to USA in solid wood packing material from Asia. However differences in the mycangial mycoflora of X. glabratus in Taiwan, Japan and USA suggest that the X. glabratus population established in USA originated in another part of Asia.

  15. Comparative pathogenicity of Vibrio spp., Photobacterium damselae ssp. damselae and five isolates of Aeromonas salmonicida ssp. achromogenes in juvenile Atlantic halibut (Hippoglossus hippoglossus).

    Science.gov (United States)

    Bowden, T J; Bricknell, I R; Preziosi, B M

    2018-01-01

    Juvenile Atlantic halibut (~100 mg, Hippoglossus hippoglossus) were exposed to Vibrio proteolyticus, a Vibrio spp. isolate, Photobacterium damselae ssp. damselae and five different isolates of Aeromonas salmonicida ssp. achromogenes via an hour-long bath immersion to ascertain their variation in pathogenicity to this fish species. Results were analysed using Kaplan-Meier survival analysis. Analysis of the data from challenges using A. salmonicida ssp. achromogenes revealed three survival values of zero and a spread of values from 0 to 28.43. Challenges using a Vibrio spp isolate, V. proteolyticus and P. damselae resulted in Kaplan-Meier survival estimates of 31.21, 50.41 and 57.21, respectively. As all bacterial species tested could induce juvenile halibut mortalities, they must all be considered as potential pathogens. However, the degree of pathogenicity of A. salmonicida is isolate dependent. © 2017 John Wiley & Sons Ltd.

  16. Enhancement of host defense against pathogens by antimicrobial peptides : a new approach to combat microbial drug resistance

    NARCIS (Netherlands)

    Does, Anne Margaretha van der

    2011-01-01

    Due to their abilities to eliminate pathogens and modulate host’s immune responses, antimicrobial peptides are considered as potential alternatives for the treatment of infections with (multi-drug resistant) pathogens. In this thesis the immunomodulatory actions of two peptides have been

  17. Longterm storage of post-packaged bread by controlling spoilage pathogens using Lactobacillus fermentum C14 isolated from homemade curd.

    Directory of Open Access Journals (Sweden)

    Soma Barman

    Full Text Available One potent lactic acid bacterial strain C14 with strong antifungal activity was isolated from homemade curd. Based on morphological as well as biochemical characters and 16S rDNA sequence homology the strain was identified as Lactobacillus fermentum. It displayed a wide antimicrobial spectrum against both Gram-positive and Gram-negative pathogenic bacteria, and also against number of food spoilage, plant and human pathogenic fungi. The cell free supernatant (CFS of the strain C14 was also effective against the fungi tested. Inhibition of radial growth of Penicillium digitatum, Trichophyton rubrum and Mucor sp. was noticed in the presence of CFS of C14 even at low concentration (1%. More than 94.3 ± 1.6% and 91.5 ± 2.2% inhibition of conidial germination of P. digitatum and Mucor sp. were noticed in the presence of 10-fold-concentrated CFS of C14. Massive deformation of the fungal mycelia was observed by SEM studies, and losses of cellular proteins and DNA are also evident upon its treatment with C14. HPLC analysis revealed the presence of phenyl lactic acid, lactic acid along with some unidentified compounds in the antifungal extract. Challenge experiment showed immense potential of the strain C14 in preventing the spoilage of bread samples caused by Mucor sp. and Bacillus subtilis. The bread samples remained fresh upto 25 days even after inoculation with Mucor sp. (3.7 × 104 spores /ml and B. subtilis (4.6 × 104 CFU /ml. Along with the antifungal properties, the isolated lactic acid bacterial strain also showed very good antioxidant activities. Unchanged level of liver enzymes serum glutamic pyruvic transaminase and serum glutamic oxaloacetic transaminase in albino mice upon feeding with C14 also suggested non-toxic nature of the bacterial isolate.

  18. Isolation and characterization of pathogenic Vibrio alginolyticus from sea cage cultured cobia (Rachycentron canadum (Linnaeus 1766)) in India.

    Science.gov (United States)

    Rameshkumar, P; Nazar, A K A; Pradeep, M A; Kalidas, C; Jayakumar, R; Tamilmani, G; Sakthivel, M; Samal, A K; Sirajudeen, S; Venkatesan, V; Nazeera, B M

    2017-11-01

    Mass mortalities of cobia, Rachycentron canadum, sub-adults occurred during August 2013 in cage culture in the Gulf of Mannar, Mandapam Tamil Nadu, India. The epizootic of disease was started with typical classical clinical signs followed by acute mortality. Grossly, severe haemorrhage and congestion were observed in the gastric mucosa. The abdomen was distended with peritoneal fluid. The heart revealed haemopericardium and fibrinous pericardium. Histologically, the gastric mucosa showed severe erosion and necrosis. Haemorrhagic pericarditis and an increased size of the melano macrophage centre (MMC) in the tail kidney were other histopathological changes. Vibrio sp. was isolated from the gastric lesions and heart blood swab of moribund fishes and it was found to be virulent to the cobia fingerlings. After the challenge, the same bacterium could be re-isolated from moribund fingerlings. The 16S ribosomal RNA of the isolate was amplified and blast analysis of the sequence confirmed that the pathogen was Vibrio alginolyticus. The confirmation was also correlated with its cultural, biochemical and pathomorphological changes. This is the second report and the first incidence of epizootics with severe pathological lesions in cultured cobia in India. The study throws light on the pathology of vibriosis. By practising cage farm management measures, occurrences of infection may be prevented. The epizootics of vibriosis caused serious economic losses to farmers. Natural blooms of the pathogen can be prevented by sea cage management measures such as, changing the inner net of the cages, changing the location of the cages to relatively clean water (about 50 m apart) from the affected site and providing shade over the cages while the water temperature rises. Supplementation of the feed with immunostimulants and mineral mixture may be practised to improve the immune response against infection. Early diagnosis and sea cage management measures may prevent occurrences of the

  19. High-throughput sequencing reveals microbial communities in drinking water treatment sludge from six geographically distributed plants, including potentially toxic cyanobacteria and pathogens.

    Science.gov (United States)

    Xu, Hangzhou; Pei, Haiyan; Jin, Yan; Ma, Chunxia; Wang, Yuting; Sun, Jiongming; Li, Hongmin

    2018-04-10

    The microbial community structures of drinking water treatment sludge (DWTS) generated for raw water (RW) from different locations and with different source types - including river water, lake water and reservoir water -were investigated using high-throughput sequencing. Because the unit operations in the six DWTPs were similar, community composition in fresh sludge may be determined by microbial community in the corresponding RW. Although Proteobacteria, Cyanobacteria, Bacteroidetes, Firmicutes, Verrucomicrobia, and Planctomycetes were the dominant phyla among the six DWTS samples, no single phylum exhibited similar abundance across all the samples, owing to differences in total phosphorus, chemical oxygen demand, Al, Fe, and chloride in RW. Three genera of potentially toxic cyanobacteria (Planktothrix, Microcystis and Cylindrospermopsis), and four potential pathogens (Escherichia coli, Bacteroides ovatus, Prevotella copri and Rickettsia) were found in sludge samples. Because proliferation of potentially toxic cyanobacteria and Rickettsia in RW was mainly affected by nutrients, while growth of Escherichia coli, Bacteroides ovatus and Prevotella copri in RW may be influenced by Fe, control of nutrients and Fe in RW is essential to decrease toxic cyanobacteria and pathogens in DWTS. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Molecular characterization and phylogenetic analysis of highly pathogenic Vibrio alginolyticus strains isolated during mortality outbreaks in cultured Ruditapes decussatus juvenile.

    Science.gov (United States)

    Mechri, Badreddine; Monastiri, Abir; Medhioub, Amel; Medhioub, Mohamed Nejib; Aouni, Mahjoub

    2017-10-01

    In the summer of 2008 and 2009, a series of mortalities in growing out seeds of R. decussatus juveniles were occurred in the eastern Tunisian littoral. Nine predominant bacterial strains were isolated from dead and moribund juveniles and characterized as Vibrio alginolyticus. These isolates were subjected to biochemical and molecular characterization. All the Vibrio strains were tested for their susceptibility against the most widely used antibiotic in aquaculture as well as, the assessment of the presence of erythromycin (emrB) and tetracycline (tetS) resistance genes among the tested bacteria. The degree of genetic relatedness between V. alginolyticus strains was evaluated on the basis of the Entero-Bacterial Repetitive Intergenic Consensus (ERIC) and the Random Amplification of Polymorphic DNA-PCR (RAPD-PCR) approaches. We also looked for siderophore activity and the ability to grow under iron limitation. Furthermore, the pathogenic potential of the tested isolates was evaluated using R. decussatus larva and juveniles as infection models. On antimicrobial susceptibility test, Vibrio strains exhibited total resistance to at least four antibiotics. The MICs data revealed that flumequine and oxolinic acid were the most effective antibiotics to control the studied bacteria. Results also showed that studied antibiotics resistance genes were widely disseminated in the genome of V. alginolyticus strains. Both ERIC and RAPD-PCR fingerprinting showed the presence of genetic variation among Vibrio isolates. However, RAPD typing exhibited a higher discriminative potential than ERIC-PCR. Besides, we reported here for the first time the co-production of catechol and hydroxamte by V. alginolyticus species. The challenge experiment showed that most of Vibrio isolates caused high mortality rates for both larva and juveniles at 48-h post-exposure to a bacterial concentration of 10 6  CFU/ml. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Pathogenicity of Phytophthora isolates originating from several woody hosts in Bulgaria and Poland

    Directory of Open Access Journals (Sweden)

    Lyubenova Aneta B.

    2016-09-01

    Full Text Available Our aim was to examine the virulence of eight Phytophthora isolates belonging to three species (Phytophthora cryptogea, Phytophthora plurivora and Phytophthora quercina obtained from diverse European ecosystems (in Bulgaria, Poland and Germany towards three forest tree hosts – English oak (Quercus robur L., Turkey oak (Quercus cerris L. and European beech (Fagus sylvatica L..

  2. INHIBITION OF PATHOGENS BY SPOROGENIC BACTERIA ISOLATED FROM HONEY OF Melipona sp. (APIDAE: APINAE: MELIPONINI

    Directory of Open Access Journals (Sweden)

    KELY DAMIANA NOVAES DA SILVA

    2016-01-01

    Full Text Available The aim of this study was to isolate sporogenic bacteria from the honey of stingless bees Melipona sp., in dry forest, and to evaluate their antagonistic potential for medicinal employment purposes and animal production. The honey samples were collected in Serra Talhada - PE, where honey was taken from four different hives (in triplicate, totaling 12 samples. The samples were diluted and subjected to 80 ºC for 20 minutes to eliminate vegetative cells. The dilutions were plated onto nutrient agar and incubated at 30 ºC for 72 hours. Then the colony forming units (CFU were quantified. The samples were also plated onto malt agar and Sabouraud agar, and incubated at 30 ºC for 14 days for the growth of yeast and molds. Total and fecal coliforms were quantified by the most probable number method (MPN. Seven isolates (I of sporogenic bacteria ( Bacillus were obtained, however only four showed probiotic potential. Isolate I - 5 showed the greatest probiotic potential and inhibited the growth of Escherichia coli , Klebsiella sp., Pseudomonas aeruginosa, Salmonella sp., and Staphylococcus aureus . The growth of the Sarcina sp. was not inhibited by any isolate. No yeast, molds or coliforms were found. The Melipona sp. honey is a source of spore - forming bacteria and is antagonistic to microorganisms that contaminate honey. It has good microbiological quality.

  3. Isolation and Characterization of Mobile Genetic Elements from Microbial Assemblages Obtained from the Field Research Center Site

    Energy Technology Data Exchange (ETDEWEB)

    Patricia Sobecky; Cassie Hodges; Kerri Lafferty; Mike Humphreys; Melanie Raimondo; Kristin Tuttle; Tamar Barkay

    2004-03-17

    Considerable knowledge has been gained from the intensive study of a relatively limited group of bacterial plasmids. Recent efforts have begun to focus on the characterization of, at the molecular level, plasmid populations and associated mobile genetic elements (e.g., transposons, integrons) occurring in a wider range of aquatic and terrestrial habitats. Surprisingly, however, little information is available regarding the incidence and distribution of mobile genetic elements extant in contaminated subsurface environments. Such studies will provide greater knowledge on the ecology of plasmids and their contributions to the genetic plasticity (and adaptation) of naturally occurring subsurface microbial communities. We requested soil cores from the DOE NABIR Field Research Center (FRC) located on the Oak Ridge Reservation. The cores, received in February 2003, were sampled from four areas on the Oak Ridge Site: Area 1, Area 2, Area 3 (representing contaminated subsurface locales) and the background reference sites. The average core length (24 in) was subdivided into three profiles and soil pH and moisture content were determined. Uranium concentration was also determined in bulk samples. Replicate aliquots were fixed for total cell counts and for bacterial isolation. Four different isolation media were used to culture aerobic and facultative microbes from these four study areas. Colony forming units ranged from a minimum of 100 per gram soil to a maximum of 10,000 irrespective of media composition used. The vast majority of cultured subsurface isolates were gram-positive isolates and plasmid characterization was conducted per methods routinely used in the Sobecky laboratory. The percentage of plasmid incidence ranged from 10% to 60% of all isolates tested. This frequency appears to be somewhat higher than the incidence of plasmids we have observed in other habitats and we are increasing the number of isolates screened to confirm this observation. We are also

  4. Microbial Profile of Soil-Free versus In-Soil Grown Lettuce and Intervention Methodologies to Combat Pathogen Surrogates and Spoilage Microorganisms on Lettuce

    Directory of Open Access Journals (Sweden)

    Sujata A. Sirsat

    2013-11-01

    Full Text Available Aquaponics is an effective method to practice sustainable agriculture and is gaining popularity in the US; however, the microbial safety of aquaponically grown produce needs to be ascertained. Aquaponics is a unique marriage of fish production and soil-free produce (e.g., leafy greens production. Fish are raised in fresh water tanks that are connected to water filled beds where fruits and vegetables are grown. The fish bi-products create nutrient-rich water that provides the key elements for the growth of plants and vegetables. The objective of this study was to perform a comparative analysis of the microbial safety and quality of aquaponic lettuce and soil grown lettuce (conventional, bagged, certified organic, and field lettuce. Following this, an intervention study was performed to combat foodborne pathogen surrogates (Salmonella and E. coli, spoilage, and fecal microorganisms using 2.5% acetic acid. The results of the comparative analysis study showed that aquaponically grown lettuce had significantly lower concentration of spoilage and fecal microorganisms compared to in-soil grown lettuce. The intervention study showed that diluted vinegar (2.5% acetic acid significantly reduced Salmonella, E. coli, coliforms, and spoilage microorganisms on fresh lettuce by 2 to 3 log CFU/g. Irrespective of growing methods (in-soil or soilless, it is crucial to incorporate good agricultural practices to reduce microbial contamination on fresh produce. The intervention employed in this study can be proposed to small farmers and consumers to improve quality and safety of leafy greens.

  5. Microbial Profile of Soil-Free versus In-Soil Grown Lettuce and Intervention Methodologies to Combat Pathogen Surrogates and Spoilage Microorganisms on Lettuce.

    Science.gov (United States)

    Sirsat, Sujata A; Neal, Jack A

    2013-11-11

    Aquaponics is an effective method to practice sustainable agriculture and is gaining popularity in the US; however, the microbial safety of aquaponically grown produce needs to be ascertained. Aquaponics is a unique marriage of fish production and soil-free produce (e.g., leafy greens) production. Fish are raised in fresh water tanks that are connected to water filled beds where fruits and vegetables are grown. The fish bi-products create nutrient-rich water that provides the key elements for the growth of plants and vegetables. The objective of this study was to perform a comparative analysis of the microbial safety and quality of aquaponic lettuce and soil grown lettuce (conventional, bagged, certified organic, and field lettuce). Following this, an intervention study was performed to combat foodborne pathogen surrogates ( Salmonella and E. coli ), spoilage, and fecal microorganisms using 2.5% acetic acid. The results of the comparative analysis study showed that aquaponically grown lettuce had significantly lower concentration of spoilage and fecal microorganisms compared to in-soil grown lettuce. The intervention study showed that diluted vinegar (2.5% acetic acid) significantly reduced Salmonella , E. coli , coliforms, and spoilage microorganisms on fresh lettuce by 2 to 3 log CFU/g. Irrespective of growing methods (in-soil or soilless), it is crucial to incorporate good agricultural practices to reduce microbial contamination on fresh produce. The intervention employed in this study can be proposed to small farmers and consumers to improve quality and safety of leafy greens.

  6. Antimicrobial resistance in gram-positive pathogens isolated in the UK between October 1996 and January 1997.

    Science.gov (United States)

    Andrews, J; Ashby, J; Jevons, G; Lines, N; Wise, R

    1999-05-01

    Antimicrobial resistance in gram-positive pathogens from 30 centres in the UK (ten Teaching, ten Associate Teaching and ten District General Hospitals) was studied over a 4 month period between October 1996 and January 1997. High-level resistance (HLR) and low-level resistance (LLR) to penicillin amongst pneumococci was 3.3% and 3.4%, respectively. However, considerable variation in resistance rates was observed depending on geographical location (LLR range 0-15.4% and HLR range 0-30.8%). Considerable variation in resistance rates was also observed for Staphylococcus aureus to methicillin, with rates ranging from 0% to 56.7% depending on locality. Using conventional MIC methodology, none of the isolates of S. aureus was considered as having reduced sensitivity to vancomycin. However, eight isolates grew on Brain Heart Infusion Agar containing vancomycin (4 mg/L) after prolonged incubation and are therefore worthy of further investigation by electron microscopy. With Enterococcus faecalis, resistance rates were similar between the three types of hospital and only four isolates were considered resistant to glycopeptide antibiotics (one vanA and three vanB phenotype).

  7. The first pathogenic Yersinia enterocolitica bioserotype 4/O:3 strain isolated from a hunted wild boar (Sus scrofa) in Poland.

    Science.gov (United States)

    Bancerz-Kisiel, A; Platt-Samoraj, A; Szczerba-Turek, A; Syczyło, K; Szweda, W

    2015-10-01

    The objective of this study was to identify the bioserotypes and virulence markers of Yersinia enterocolitica strains isolated from wild boars in Poland. Bacteriological examination of 302 rectal swabs from 151 wild boars resulted in the isolation of 40 Y. enterocolitica strains. The majority of the examined strains (n = 30), belonged to bioserotype 1A/NI. The presence of individual Y. enterocolitica strains belonging to bioserotypes 1B/NI (3), 1A/O:8 (2), 1A/O:27 (2), 2/NI (1), 2/O:9 (1) and 4/O:3 (1) was also demonstrated. Amplicons corresponding to ail and ystA genes were observed only in one Y. enterocolitica strain--bioserotype 4/O:3. The ail and ystB gene amplicons were noted in 11 Y. enterocolitica biotype 1A strains, although single amplicons of ystB gene were found in 28 of the tested samples. In four out of eight cases when two Y. enterocolitica strains were isolated from the same animal, the strains differed in biotype, serotype or virulence markers. The European population of wild boars continues to grow and spread to new areas, therefore, wild boars harbouring potentially pathogenic Y. enterocolitica 4/O:3 strains pose a challenge to public health.

  8. Ecosystem screening approach for pathogen-associated microorganisms affecting host disease.

    Science.gov (United States)

    Galiana, Eric; Marais, Antoine; Mura, Catherine; Industri, Benoît; Arbiol, Gilles; Ponchet, Michel

    2011-09-01

    The microbial community in which a pathogen evolves is fundamental to disease outcome. Species interacting with a pathogen on the host surface shape the distribution, density, and genetic diversity of the inoculum, but the role of these species is rarely determined. The screening method developed here can be used to characterize pathogen-associated species affecting disease. This strategy involves three steps: (i) constitution of the microbial community, using the pathogen as a trap; (ii) community selection, using extracts from the pathogen as the sole nutrient source; and (iii) molecular identification and the screening of isolates focusing on their effects on the growth of the pathogen in vitro and host disease. This approach was applied to a soilborne plant pathogen, Phytophthora parasitica, structured in a biofilm, for screening the microbial community from the rhizosphere of Nicotiana tabacum (the host). Two of the characterized eukaryotes interfered with the oomycete cycle and may affect the host disease. A Vorticella species acted through a mutualistic interaction with P. parasitica, disseminating pathogenic material by leaving the biofilm. A Phoma species established an amensal interaction with P. parasitica, strongly suppressing disease by inhibiting P. parasitica germination. This screening method is appropriate for all nonobligate pathogens. It allows the definition of microbial species as promoters or suppressors of a disease for a given biotope. It should also help to identify important microbial relationships for ecology and evolution of pathogens.

  9. The efficacy of different anti-microbial metals at preventing the formation of, and eradicating bacterial biofilms of pathogenic indicator strains.

    Science.gov (United States)

    Gugala, Natalie; Lemire, Joe A; Turner, Raymond J

    2017-06-01

    The emergence of multidrug-resistant pathogens and the prevalence of biofilm-related infections have generated a demand for alternative anti-microbial therapies. Metals have not been explored in adequate detail for their capacity to combat infectious disease. Metal compounds can now be found in textiles, medical devices and disinfectants-yet, we know little about their efficacy against specific pathogens. To help fill this knowledge gap, we report on the anti-microbial and antibiofilm activity of seven metals: silver, copper, titanium, gallium, nickel, aluminum and zinc against three bacterial strains, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. To evaluate the capacity of metal ions to prevent the growth of, and eradicate biofilms and planktonic cells, bacterial cultures were inoculated in the Calgary Biofilm Device (minimal biofilm eradication concentration) in the presence of the metal salts. Copper, gallium and titanium were capable of preventing planktonic and biofilm growth, and eradicating established biofilms of all tested strains. Further, we observed that the efficacies of the other tested metal salts displayed variable efficacy against the tested strains. Further, contrary to the enhanced resistance anticipated from bacterial biofilms, particular metal salts were observed to be more effective against biofilm communities versus planktonic cells. In this study, we have demonstrated that the identity of the bacterial strain must be considered before treatment with a particular metal ion. Consequent to the use of metal ions as anti-microbial agents to fight multidrug-resistant and biofilm-related infections increases, we must aim for more selective deployment in a given infectious setting.

  10. Microbial community profiling of fresh basil and pitfalls in taxonomic assignment of enterobacterial pathogenic species based upon 16S rRNA amplicon sequencing.

    Science.gov (United States)

    Ceuppens, Siele; De Coninck, Dieter; Bottledoorn, Nadine; Van Nieuwerburgh, Filip; Uyttendaele, Mieke

    2017-09-18

    Application of 16S rRNA (gene) amplicon sequencing on food samples is increasingly applied for assessing microbial diversity but may as unintended advantage also enable simultaneous detection of any human pathogens without a priori definition. In the present study high-throughput next-generation sequencing (NGS) of the V1-V2-V3 regions of the 16S rRNA gene was applied to identify the bacteria present on fresh basil leaves. However, results were strongly impacted by variations in the bioinformatics analysis pipelines (MEGAN, SILVAngs, QIIME and MG-RAST), including the database choice (Greengenes, RDP and M5RNA) and the annotation algorithm (best hit, representative hit and lowest common ancestor). The use of pipelines with default parameters will lead to discrepancies. The estimate of microbial diversity of fresh basil using 16S rRNA (gene) amplicon sequencing is thus indicative but subject to biases. Salmonella enterica was detected at low frequencies, between 0.1% and 0.4% of bacterial sequences, corresponding with 37 to 166 reads. However, this result was dependent upon the pipeline used: Salmonella was detected by MEGAN, SILVAngs and MG-RAST, but not by QIIME. Confirmation of Salmonella sequences by real-time PCR was unsuccessful. It was shown that taxonomic resolution obtained from the short (500bp) sequence reads of the 16S rRNA gene containing the hypervariable regions V1-V3 cannot allow distinction of Salmonella with closely related enterobacterial species. In conclusion 16S amplicon sequencing, getting the status of standard method in microbial ecology studies of foods, needs expertise on both bioinformatics and microbiology for analysis of results. It is a powerful tool to estimate bacterial diversity but amenable to biases. Limitations concerning taxonomic resolution for some bacterial species or its inability to detect sub-dominant (pathogenic) species should be acknowledged in order to avoid overinterpretation of results. Copyright © 2017 Elsevier B

  11. Clinical isolates of Yersinia enterocolitica Biotype 1A represent two phylogenetic lineages with differing pathogenicity-related properties

    Directory of Open Access Journals (Sweden)

    Sihvonen Leila M

    2012-09-01

    Full Text Available Abstract Background Y. enterocolitica biotype (BT 1A strains are often isolated from human clinical samples but their contribution to disease has remained a controversial topic. Variation and the population structure among the clinical Y. enterocolitica BT 1A isolates have been poorly characterized. We used multi-locus sequence typing (MLST, 16S rRNA gene sequencing, PCR for ystA and ystB, lipopolysaccharide analysis, phage typing, human serum complement killing assay and analysis of the symptoms of the patients to characterize 298 clinical Y. enterocolitica BT 1A isolates in order to evaluate their relatedness and pathogenic potential. Results A subset of 71 BT 1A strains, selected based on their varying LPS patterns, were subjected to detailed genetic analyses. The MLST on seven house-keeping genes (adk, argA, aroA, glnA, gyrB, thrA, trpE conducted on 43 of the strains discriminated them into 39 MLST-types. By Bayesian analysis of the population structure (BAPS the strains clustered conclusively into two distinct lineages, i.e. Genetic groups 1 and 2. The strains of Genetic group 1 were more closely related (97% similarity to the pathogenic bio/serotype 4/O:3 strains than Genetic group 2 strains (95% similarity. Further comparison of the 16S rRNA genes of the BT 1A strains indicated that altogether 17 of the 71 strains belong to Genetic group 2. On the 16S rRNA analysis, these 17 strains were only 98% similar to the previously identified subspecies of Y. enterocolitica. The strains of Genetic group 2 were uniform in their pathogenecity-related properties: they lacked the ystB gene, belonged to the same LPS subtype or were of rough type, were all resistant to the five tested yersiniophages, were largely resistant to serum complement and did not ferment fucose. The 54 strains in Genetic group 1 showed much more variation in these properties. The most commonly detected LPS types were similar to the LPS types of reference strains with serotypes O

  12. Streptococcus dysgalactiae subsp. dysgalactiae isolated from milk of the bovine udder as emerging pathogens: In vitro and in vivo infection of human cells and zebrafish as biological models.

    Science.gov (United States)

    Alves-Barroco, Cinthia; Roma-Rodrigues, Catarina; Raposo, Luís R; Brás, Catarina; Diniz, Mário; Caço, João; Costa, Pedro M; Santos-Sanches, Ilda; Fernandes, Alexandra R

    2018-03-25

    Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) is a major cause of bovine mastitis and has been regarded as an animal-restricted pathogen, although rare infections have been described in humans. Previous studies revealed the presence of virulence genes encoded by phages of the human pathogen Group A Streptococcus pyogenes (GAS) in SDSD isolated from the milk of bovine udder with mastitis. The isolates SDSD VSD5 and VSD13 could adhere and internalize human primary keratinocyte cells, suggesting a possible human infection potential of bovine isolates. In this work, the in vitro and in vivo potential of SDSD to internalize/adhere human cells of the respiratory track and zebrafish as biological models was evaluated. Our results showed that, in vitro, bovine SDSD strains could interact and internalize human respiratory cell lines and that this internalization was dependent on an active transport mechanism and that, in vivo, SDSD are able to cause invasive infections producing zebrafish morbidity and mortality. The infectious potential of these isolates showed to be isolate-specific and appeared to be independent of the presence or absence of GAS phage-encoded virulence genes. Although the infection ability of the bovine SDSD strains was not as strong as the human pathogenic S. pyogenes in the zebrafish model, results suggested that these SDSD isolates are able to interact with human cells and infect zebrafish, a vertebrate infectious model, emerging as pathogens with zoonotic capability. © 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  13. Metabolic versatility of Gram-positive microbial isolates from contaminated river sediments

    International Nuclear Information System (INIS)

    Narancic, Tanja; Djokic, Lidija; Kenny, Shane T.; O’Connor, Kevin E.; Radulovic, Vanja; Nikodinovic-Runic, Jasmina; Vasiljevic, Branka

    2012-01-01

    Highlights: ► Thirty-four isolated Gram-positive bacteria could degrade wide range of aromatic pollutants. ► Nine isolates could grow in the presence of extremely high levels of heavy metals. ► Twelve isolates accumulated polyphosphate, 3 polyhydroxybutyrate, 4 exopolysaccharides. ► The incidence of multiple antibiotic resistance markers among isolates was low. - Abstract: Gram-positive bacteria from river sediments affected by the proximity of a petrochemical industrial site were isolated and characterized with respect to their ability to degrade a wide range of aromatic compounds. In this study we identified metabolically diverse Gram-positive bacteria capable of growth on wide range aromatic compounds in the presence of heavy metals and with the ability to accumulate biopolymers. Thirty-four isolates that were able to use 9 or more common aromatic pollutants, such as benzene, biphenyl, naphthalene etc. as a sole source of carbon and energy included members of Bacillus, Arthrobacter, Rhodococcus, Gordonia, Streptomyces, and Staphylococcus genus. Rhodococcus sp. TN105, Gordonia sp. TN103 and Arthrobacter sp. TN221 were identified as novel strains. Nine isolates were able to grow in the presence of one or more metals (mercury, cadmium, nickel) at high concentration (100 mM). Seven isolates could degrade 15 different aromatic compounds and could grow in the presence of one or more heavy metals. Two of these isolates were resistant to multiple antibiotics including erythromycin and nalidixic acid. One third of isolates could accumulate at least one biopolymer. Twelve isolates (mainly Bacillus sp. and Arthrobacter sp.) accumulated polyphosphate, 3 Bacillus sp. accumulated polyhydroxybutyrate, while 4 isolates could accumulate exopolysaccharides.

  14. Bio-prospecting of soil Streptomyces and its bioassay-guided isolation of microbial derived auxin with antifungal properties.

    Science.gov (United States)

    Saravana Kumar, P; Yuvaraj, P; Gabrial Paulraj, M; Ignacimuthu, S; Abdullah Al-Dhabi, N

    2018-06-05

    The present study was aimed to isolate bioactive actinomycetes with antifungal properties. Twenty-seven distinct soil derived actinomycetes were investigated for their antifungal activities. Among these, one isolate exhibited significant antifungal activity. Phenotypic and 16s rRNA gene sequence analysis strongly suggested that the active isolate BG4 belonged to the genus Streptomyces. Further, the chemical investigation of the active extract resulted in the isolation of a major compound and it was structurally elucidated as phenyl acetic acid (PAA). PAA exhibited promising antifungal activity with 100% inhibition, ranging from 31.25 to 25μg/mL. It is to be noted that PAA is naturally occurring and biologically active auxin. In addition, it has also been hypothesized that phytohormone endorsing the source of soil-symbionts has similar pathways for synthesizing compounds and its congeners of host due to horizontal gene transfer. These findings demonstrate that microbially derived phytohormone can be used to treat fungal infections. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  15. Long-term monitoring of waterborne pathogens and microbial source tracking markers in paired agricultural watersheds under controlled and conventional tile drainage management.

    Science.gov (United States)

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C; Jones, Tineke H; Khan, Izhar U H; Marti, Romain; Sunohara, Mark D; Topp, Edward; Lapen, David R

    2014-06-01

    Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  16. Long-Term Monitoring of Waterborne Pathogens and Microbial Source Tracking Markers in Paired Agricultural Watersheds under Controlled and Conventional Tile Drainage Management

    Science.gov (United States)

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A.; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C.; Jones, Tineke H.; Khan, Izhar U. H.; Marti, Romain; Sunohara, Mark D.; Topp, Edward

    2014-01-01

    Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. PMID:24727274

  17. Pathogenicity of a strain of Yersinia pseudotuberculosis isolated from a pig with porcine colitis syndrome.

    Science.gov (United States)

    Neef, N A; Lysons, R J

    1994-07-16

    A strain of Yersinia pseudotuberculosis (NCTC 12718), isolated from a seven-week-old pig suffering from an ulcerative typhlocolitis, was inoculated orally into 16 growing pigs in two separate experiments. At necropsy 10 days later, typhlocolitis was present in nine of the pigs, and it was accompanied by diarrhoea in four cases. In both the original case and in the experimental pigs, the typhlocolitis was characterised by microabscesses of the lamina propria, frequently involving ulceration or erosion of the surface epithelium. The organism was of serotype IIa, which has not been isolated previously from pigs in the United Kingdom. Y pseudotuberculosis may be the aetiological agent responsible in some cases of porcine colitis syndrome.

  18. Leptospira mayottensis sp. nov., a pathogenic species of the genus Leptospira isolated from humans.

    Science.gov (United States)

    Bourhy, Pascale; Collet, Louis; Brisse, Sylvain; Picardeau, Mathieu

    2014-12-01

    A group of strains representing species of the genus Leptospira, isolated from patients with leptospirosis in Mayotte (Indian Ocean), were previously found to be considerably divergent from other known species of the genus Leptospira. This was inferred from sequence analysis of rrs (16S rRNA) and other genetic loci and suggests that they belong to a novel species. Two strains from each serogroup currently identified within this novel species were studied. Spirochaete, aerobic, motile, helix-shaped strains grew well at 30-37 °C, but not at 13 °C or in the presence of 8-azaguanine. Draft genomes of the strains were also analysed to study the DNA relatedness with other species of the genus Leptospira. The new isolates formed a distinct clade, which was most closely related to Leptospira borgpetersenii, in multilocus sequence analysis using concatenated sequences of the genes rpoB, recA, fusA, gyrB, leuS and sucA. Analysis of average nucleotide identity and genome-to-genome distances, which have recently been proposed as reliable substitutes for classical DNA-DNA hybridization, further confirmed that these isolates should be classified as representatives of a novel species. The G+C content of the genomic DNA was 39.5 mol%. These isolates are considered to represent a novel species, for which the name Leptospira mayottensis sp. nov. is proposed, with 200901116(T) ( = CIP 110703(T) = DSM 28999(T)) as the type strain. © 2014 IUMS.

  19. Bioassay-guided isolation and evaluation of antimicrobial compounds from Ixora megalophylla against some oral pathogens.

    Science.gov (United States)

    Panyo, J; Matsunami, K; Panichayupakaranant, P

    2016-09-01

    Context Ixora megalophylla Chamch. (Rubiaceae) is a new plant species recently found in southern Thailand. Ethyl acetate extracts of its leaves and stems showed antimicrobial activities. Objectives To isolate and identify the antimicrobial compounds from I. megalophylla leaves and stems. Materials and methods The dried leaves (1.7 kg) and stems (3.5 kg) were consecutively extracted with petroleum ether (5 L × 4), ethyl acetate (5 L × 3) and ethanol (5 L × 4) under reflux conditions. The ethyl acetate extract was subjected to an antimicrobial assay guided isolation with Candida albicans and Streptococcus mutans. Compounds 1-10 were identified by (1)H NMR, (13)C NMR and EI-MS. Minimal lethal concentration (MLC) against C. albicans and Streptococcus spp. was determined using a broth microdilution method for 48 and 24 h, respectively. Results and discussion On the basis of the antimicrobial assay guided isolation, 10 known compounds, including vanillic acid (1), syringic acid (2), 4-hydroxy benzaldehyde (3), scopoletin (4), loliolide (5), syringaldehyde (6), sinapaldehyde (7), coniferaldehyde (8), syringaresinol (9) and 2,2'-dithiodipyridine (10), were identified. Compounds 1-5 were purified from the ethyl acetate extract of the leaves, while 6-9 and 10 were from the ethyl acetate and ethanol extracts of the stems, respectively. Among these isolates, 10 showed the strongest antibacterial activities against S. mutans and Streptococcus mitis, with minimum inhibitory concentrations (MICs) of 2-4 μg/mL, and MLC of 4 μg/mL, as well as having a weak antifungal activity against C. albicans (MIC of 125 μg/mL). This is the first report of the antimicrobial activities of 10.

  20. The Effect of Lactic Acid Bacteria Isolates on the Urinary Tract Pathogens to Infants In Vitro

    OpenAIRE

    Lim, In Seok; Lee, Ho Seok; Kim, Won Yong

    2009-01-01

    Urinary tract infections are common clinical problems in children, even though lots of treatment strategies have been tried. Many studies of the application of probiotics for urinary tract infection in female adults exist, but there is a lack of studies in children. The aims of this study were to screen probiotic strains for inhibiting the uropathogens in vitro, to find candidates for in vivo study. Nine strains of E. coli were isolated from children with urinary tract infection and six uropa...

  1. Dynamics of extended-spectrum cephalosporin resistance in pathogenic Escherichia coli isolated from diseased pigs in Quebec, Canada.

    Science.gov (United States)

    Jahanbakhsh, Seyedehameneh; Smith, Matthew G; Kohan-Ghadr, Hamid-Reza; Letellier, Ann; Abraham, Sam; Trott, Darren J; Fairbrother, John Morris

    2016-08-01

    The aim of this study was to investigate the evolution with time of ceftiofur-resistant Escherichia coli clinical isolates from pigs in Québec, Canada, between 1997 and 2012 with respect to pathotypes, clones and antimicrobial resistance. Eighty-five ceftiofur-resistant E. coli isolates were obtained from the OIE (World Organisation for Animal Health) Reference Laboratory for Escherichia coli. The most prevalent pathovirotypes were enterotoxigenic E. coli (ETEC):F4 (40%), extraintestinal pathogenic E. coli (ExPEC) (16.5%) and Shiga toxin-producing E. coli (STEC):F18 (8.2%). Susceptibility testing to 15 antimicrobial agents revealed a high prevalence of resistance to 13 antimicrobials, with all isolates being multidrug-resistant. blaCMY-2 (96.5%) was the most frequently detected β-lactamase gene, followed by blaTEM (49.4%) and blaCTX-M (3.5%). Pulsed-field gel electrophoresis (PFGE) applied to 45 representative E. coli isolates revealed that resistance to ceftiofur is spread both horizontally and clonally. In addition, the emergence of extended-spectrum β-lactamase-producing E. coli isolates carrying blaCTX-M was observed in 2011 and 2012 in distinct clones. The most predominant plasmid incompatibility (Inc) groups were IncFIB, IncI1, IncA/C and IncFIC. Resistance to gentamicin, kanamycin and chloramphenicol as well as the frequency of blaTEM and IncA/C significantly decreased over the study period, whereas the frequency of IncI1 and multidrug resistance to seven antimicrobial categories significantly increased. These findings reveal that extended-spectrum cephalosporin-resistant porcine E. coli isolates in Québec belong to several different clones with diverse antimicrobial resistance patterns and plasmids. Furthermore, blaCMY-2 was the major β-lactamase gene in these isolates. From 2011, we report the emergence of blaCTX-M in distinct clones. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  2. Antibacterial susceptibility profiles of subclinical mastitis pathogens isolated in Batna and Setif Governorates (East of Algeria

    Directory of Open Access Journals (Sweden)

    Mamache Bakir

    Full Text Available Sub-clinical mastitis is a main pathology of dairy husbandry because it is not clinically recognized by the owners and the veterinarians. For this reason, its economic loss is usually underestimated in milk production. This study has been undertaken in order to evaluate the epidemiologic situation of sub-clinicalmastitis in Batna and Setif governorates (East of Algeria. For this purpose, a detailed bacteriological study of all bacterial strains isolated from sub-clinical mastitis followed by a study of their antibacterial susceptibility profiles has been undertaken. 89 bacterial strains distributed as follows were studied: 27 strains of staphylococci among which 23 were coagulase-negative staphylococci (CNS that are generally incriminated in sub-clinical mastitis. 39 strains of streptococci among which 10 were Lactococcus lactis ssp lactis strains. 23 strains of enterobacteria represented mainly by Escherichia coli (E.coli. All these bacterial strains were isolated from cow milk of 3 different farms. The antibacterial susceptibility profiles have revealed a susceptibility of the isolated strains to a large number of antibiotics mainly to the Neomycin, the Cephalexin and the Spiramycin. [Vet. World 2011; 4(12.000: 537-541

  3. Isolation and characterization of pathogenic Vibrio alginolyticus from diseased cobia Rachycentron canadum.

    Science.gov (United States)

    Liu, Ping-Chung; Lin, Ji-Yang; Hsiao, Pei-Tze; Lee, Kuo-Kau

    2004-01-01

    Outbreaks of serious mortality among cultured juvenile cobia Rachycentron canadum L. (weighing 8-10 g) characterized by lethargy, dark skin and ascites in the peritoneal cavity while some fish possessing damaged eyes occurred in July and August of 2001 in Taiwan. Fifteen motile bacterial strains were isolated from head kidney and/or the ascites on tryptic soy agar supplemented with 1% NaCl (TSA1) and/or thiosulphate citrate bile salt (TCBS) sucrose agar plates during the two outbreaks. All the isolates were characterized and identified as Vibrio alginolyticus on the basis of biochemical characteristics, and comparisons with those of the reference strain V. alginolyticus ATCC 17749. The strain C3c01 (a representative of the 15 similar field isolates), was virulent to the cobia with an LD50 value of 3.28 x 10(4) colony forming units/g fish body weight. All the moribund/dead fish exhibited lethargy, dark skin and ascites in the peritoneal cavity as that observed in natural outbreaks. The same bacteria could be reisolated from kidney and the ascites of fish after bacterial challenge using TSA1 and TCBS plates. The results reveal that V. alginolyticus is an infectious agent of vibriosis in the cobia.

  4. Presence and Characterization of Extraintestinal Pathogenic Escherichia coli Virulence Genes in F165-Positive E. coli Strains Isolated from Diseased Calves and Pigs

    OpenAIRE

    Dezfulian, Hojabr; Batisson, Isabelle; Fairbrother, John M.; Lau, Peter C. K.; Nassar, Atef; Szatmari, George; Harel, Josée

    2003-01-01

    The virulence genotype profile and presence of a pathogenicity island(s) (PAI) were studied in 18 strains of F165-positive Escherichia coli originally isolated from diseased calves or piglets. On the basis of their adhesion phenotypes and genotypes, these extraintestinal pathogenic strains were classified into three groups. The F165 fimbrial complex consists of at least two serologically and genetically distinct fimbriae: F1651 and F1652. F1651 is encoded by the foo operon (pap-like), and F16...

  5. Effect of Lactobacillus sp. isolates supernatant on Escherichia coli O157:H7 enhances the role of organic acids production as a factor for pathogen control

    Directory of Open Access Journals (Sweden)

    Larissa B. Poppi

    2015-04-01

    Full Text Available Many attempts have been made to establish the control of foodborne pathogens through Lactobacillus isolates and their metabolism products with success being obtained in several situations. The aim of this study was to investigate the antagonistic effect of eight Lactobacillus isolates, including L. casei subsp. pseudoplantarum, L. plantarum, L. reuteri and L. delbrueckii subsp. delbrueckii, on the pathogenic Escherichia colistrain O157:H7. The inhibitory effect of pure cultures and two pooled cultures supernatants of Lactobacillus on the growth of pathogenic bacteria was evaluated by the spot agar method and by monitoring turbidity. Antimicrobial activity was confirmed for L. reuteri and L. delbrueckii subsp. delbrueckii and for a pool of lactic acid bacteria. The neutralized supernatant of the pool exerted a higher antimicrobial activity than that of the individual strains. Furthermore, D-lactic acid and acetic acid were produced during growth of the Lactobacillus isolates studied.

  6. [Phenotypic and genotypic identification of Candida strains isolated as nosocomial pathogens].

    Science.gov (United States)

    Sahiner, Fatih; Ergünay, Koray; Ozyurt, Mustafa; Ardıç, Nurittin; Hoşbul, Tuğrul; Haznedaroğlu, Tunçer

    2011-07-01

    Over the last decade, there have been important changes in the epidemiology of Candida infections and antifungal agents used to treat these infections. In recent years, Candida species have emerged as important causes of invasive infections among patients in intensive care units. One of the main goals of this study was to evaluate the molecular epidemiology of infectious Candida species isolated in our hospital and accordingly supply data for hospital infection (HI) control. The other aim of this study was to evaluate effectiveness and practical applicability of traditional and molecular methods used to identify Candida isolates to the species level. A total of 77 Candida strains that were isolated from various clinical specimens of 60 hospitalized patients (29 male, 24 female; 7 were children) were included in the study. Fifty-seven (74%) of those isolates were defined as HI agents according to Centers for Disease Control and Prevention (CDC) criteria. The most common Candida species identified as agents of HI were C.albicans (22; 38.6%), followed by C.tropicalis (14; 24.6%), C.parapsilosis (13; 22.8%), C.glabrata (7; 12.3%) and Candida spp. (1; 1.75%). It was determined that bloodstream (26; 45.6%) and urinary tract infections (24; 42.1%) were the most frequently encountered nosocomial infections caused by Candida species. In addition it was detected that the most frequent causative agent of bloodstream infections was C.parapsilosis (10; 38.5%) and of urinary tract infections was C.albicans (12; 50%). The evaluation of advantages and disadvantages of traditional phenotypic methods [germ tube formation, chlamydospore formation in corn meal agar, growth at 45°C, colony characteristics on CHROMagar Candida medium, carbohydrate assimilation properties detected by API ID 32C (BioMerieux, France) system] and some molecular techniques [polymerase chain reaction (PCR) by using ITS-1, ITS-3 and ITS 4 primers, PCR-Restriction fragment length polymorphism (RFLP), PCRRFLP

  7. Characterization of the microbial community in a lotic environment to assess the effect of pollution on nitrifying and potentially pathogenic bacteria.

    Science.gov (United States)

    Medeiros, J D; Araújo, L X; da Silva, V L; Diniz, C G; Cesar, D E; Del'Duca, A; Coelho, C M

    2014-08-01

    This study aimed to investigate microbes involved in the nitrogen cycle and potentially pathogenic bacteria from urban and rural sites of the São Pedro stream. Water samples were collected from two sites. A seasonal survey of bacterial abundance was conducted. The dissolved nutrient content was analysed. PCR and FISH analysis were performed to identify and quantify microbes involved in the nitrogen cycle and potentially pathogenic bacteria. The seasonal survey revealed that the bacterial abundance was similar along the year on the rural area but varied on the urban site. Higher concentration of dissolved nutrients in the urban area indicated a eutrophic system. Considering the nitrifying microbes, the genus Nitrobacter was found, especially in the urban area, and may act as the principal bacteria in converting nitrite into nitrate at this site. The molecular markers napA, amoA, and nfrA were more accumulated at the urban site, justifying the higher content of nutrients metabolised by these enzymes. Finally, high intensity of amplicons from Enterococcus, Streptococcus, Bacteroides/Prevotella/Porphyromonas, Salmonella, S. aureus, P. aeruginosa and the diarrheagenic lineages of E. coli were observed at the urban site. These results indicate a change in the structure of the microbial community imposed by anthrophic actions. The incidence of pathogenic bacteria in aquatic environments is of particular importance to public health, emphasising the need for sewage treatment to minimise the environmental impacts associated with urbanisation.

  8. Isolation of the highly pathogenic and zoonotic agent Burkholderia pseudomallei from a pet green Iguana in Prague, Czech Republic.

    Science.gov (United States)

    Elschner, Mandy C; Hnizdo, Jan; Stamm, Ivonne; El-Adawy, Hosny; Mertens, Katja; Melzer, Falk

    2014-11-28

    Melioidosis caused by Burkholderia (B.) pseudomallei is an endemic zoonotic disease mainly reported from northern Australia and Southeast Asia. In Europe, cases of human melioidosis have been reported only from patients travelling to endemic regions. Besides humans, B. pseudomallei has a very broad host range in domestic and wild animals. There are some reports about importation of B. pseudomallei-infected animals from endemic areas into Europe. The present report describes the first case of B. pseudomallei infection of a pet iguana in Europe. In a 5-year-old pet Iguana iguana living in a private household in Prague, Czech Republic, B. pseudomallei was isolated from pus of an abscess. The isolate VB976100 was identified by Vitek®2, MALDI-TOF mass spectrometry and polymerase chain reaction as B. pseudomallei. The molecular typing resulted in multi-locus sequence type 436 hitherto, which has been found only once worldwide in a B. pseudomallei strain isolated in the USA and originating from Guatemala. The identification as internal transcribed spacer type G indicates a close relatedness to strains mainly isolated in the Western Hemisphere. These findings support the hypothesis that the iguana became infected in this region or in a breeding facility through contact to other infected animals. The present case highlights the risk of importation of the highly pathogenic and zoonotic B. pseudomallei into non-endemic regions through animal trade. Therefore, veterinarians treating animals from these areas and physicians examining patients owning such animals should include melioidosis in differential diagnosis whenever specific symptoms appear. Furthermore, veterinary authorities responsible for supervision of traders and pet shops should be aware of this risk of zoonotic transmission.

  9. Frequent combination of antimicrobial multiresistance and extraintestinal pathogenicity in Escherichia coli isolates from urban rats (Rattus norvegicus) in Berlin, Germany.

    Science.gov (United States)

    Guenther, Sebastian; Bethe, Astrid; Fruth, Angelika; Semmler, Torsten; Ulrich, Rainer G; Wieler, Lothar H; Ewers, Christa

    2012-01-01

    Urban rats present a global public health concern as they are considered a reservoir and vector of zoonotic pathogens, including Escherichia coli. In view of the increasing emergence of antimicrobial resistant E. coli strains and the on-going discussion about environmental reservoirs, we intended to analyse whether urban rats might be a potential source of putatively zoonotic E. coli combining resistance and virulence. For that, we took fecal samples from 87 brown rats (Rattus norvegicus) and tested at least three E. coli colonies from each animal. Thirty two of these E. coli strains were pre-selected from a total of 211 non-duplicate isolates based on their phenotypic resistance to at least three antimicrobial classes, thus fulfilling the definition of multiresistance. As determined by multilocus sequence typing (MLST), these 32 strains belonged to 24 different sequence types (STs), indicating a high phylogenetic diversity. We identified STs, which frequently occur among extraintestinal pathogenic E. coli (ExPEC), such as STs 95, 131, 70, 428, and 127. Also, the detection of a number of typical virulence genes confirmed that the rats tested carried ExPEC-like strains. In particular, the finding of an Extended-spectrum beta-lactamase (ESBL)-producing strain which belongs to a highly virulent, so far mainly human- and avian-restricted ExPEC lineage (ST95), which expresses a serogroup linked with invasive strains (O18:NM:K1), and finally, which produces an ESBL-type frequently identified among human strains (CTX-M-9), pointed towards the important role, urban rats might play in the transmission of multiresistant and virulent E. coli strains. Indeed, using a chicken infection model, this strain showed a high in vivo pathogenicity. Imagining the high numbers of urban rats living worldwide, the way to the transmission of putatively zoonotic, multiresistant, and virulent strains might not be far ahead. The unforeseeable consequences of such an emerging public health

  10. Paederia foetida Linn. promoted biogenic gold and silver nanoparticles: Synthesis, characterization, photocatalytic and in vitro efficacy against clinically isolated pathogens.

    Science.gov (United States)

    Bhuyan, Bishal; Paul, Arijita; Paul, Bappi; Dhar, Siddhartha Sankar; Dutta, Pranab

    2017-08-01

    Development of newer improved therapeutic agents with efficient antimicrobial activities continues to draw attention of researchers till date. Moreover, abatement of polluting dyes released from industry with enhanced efficiency is currently being considered as challenging task for people working on material sciences. In the present study, we report a facile biogenic synthesis of gold and silver nanoparticles (NPs) in which aqueous extracts of Paederia foetida Linn. was used as reducing as well as stabilizing agent. The biosynthesized Au and Ag NPs were characterized by UV-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The photocatalytic activity of these nanoparticles were tested against Rhodamine B (RhB). The antimicrobial activity of these biosynthesized NPs were investigated against four human pathogens viz. B. cereus, E. coli, S. aureus and A. niger. Biogenic silver nanoparticles presented a strong antimicrobial activity against B. cereus (26.13) followed by E. coli (26.02), S. aureus (25.43) and A. niger (22.69). Ag NPs owing to their small size (5-25nm) could have easily penetrate into the cell membrane, disturb the metabolism, cause irretrievable damage finally leading to the microbial cell death. Interestingly biogenic gold nanoparticles didn't show any antimicrobial activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Occurrence and characterization of food-borne pathogens isolated from fruit, vegetables and sprouts retailed in the Czech Republic.

    Science.gov (United States)

    Vojkovská, Hana; Myšková, Petra; Gelbíčová, Tereza; Skočková, Alena; Koláčková, Ivana; Karpíšková, Renáta

    2017-05-01

    Food of non-animal origin is a major component of the human diet and has been considered to pose a low risk from the point of view of bacteriological safety. However, an increase in the number of outbreaks of illness caused by such pathogens and linked to the consumption of fresh fruit and vegetables have been reported from around the world recently. Salmonella spp., STEC (Shiga toxin producing Escherichia coli) and Listeria monocytogenes are among the most frequently identified agents. Additionally, the transmission of antibiotic resistant strains including also the methicillin resistant S. aureus (MRSA) to humans via the food chain is one of the greatest public health problems being confronted today. Therefore, we focused on the bacterial safety of fruit, vegetables and sprouts on sale in the Czech Republic. One strain (0.3%) of Salmonella Enteritidis phage type PT8, one strain (0.3%) of MRSA and 17 strains (5.0%) of L. monocytogenes were isolated from a total of 339 collected samples. The most problematic commodities were frozen fruit and vegetables (packed and unpacked) and fresh-cut vegetables. Our findings indicate deficiencies in hygiene practices during harvesting, processing and distribution of these commodities. Although sprouts and berries are the most likely to be contaminated by human pathogens, only two samples were positive for the presence of L. monocytogenes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Isolation, Functional Characterization and Transmissibility of p3PS10, a Multidrug Resistance Plasmid of the Fish Pathogen Piscirickettsia salmonis

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    José Saavedra

    2018-05-01

    Full Text Available Antibiotic resistance is a major public health concern due to its association with the loss of efficacy of antimicrobial therapies. Horizontal transfer events may play a significant role in the dissemination of resistant bacterial phenotypes, being mobilizable plasmids a well-known mechanism. In this study, we aimed to gain insights into the genetics underlying the development of antibiotic resistance by Piscirickettsia salmonis isolates, a bacterial fish pathogen and causative agent of salmonid piscirickettsiosis, and the main target of antibiotics used in Chilean salmon farming. We provide experimental evidence that the plasmid p3PS10, which harbors multidrug resistance genes for chloramphenicol (cat2, tetracyclines [tet(31], aminoglycosides (sat1 and aadA1, and sulfonamides (sul2, is carried by a group of P. salmonis isolates exhibiting a markedly reduced susceptibility to oxytetracycline in vitro (128–256 μg/mL of minimal inhibitory concentration, MIC. Antibiotic susceptibility analysis extended to those antibiotics showed that MIC of chloramphenicol, streptomycin, and sulfamethoxazole/trimethoprim were high, but the MIC of florfenicol remained at the wild-type level. By means of molecular cloning, we demonstrate that those genes encoding putative resistance markers are indeed functional. Interestingly, mating assays clearly show that p3PS10 is able to be transferred into and replicate in different hosts, thereby conferring phenotypes similar to those found in the original host. According to epidemiological data, this strain is distributed across aquaculture settings in southern Chile and is likely to be responsible for oxytetracycline treatment failures. This work demonstrates that P. salmonis is more versatile than it was thought, capable of horizontally transferring DNA, and probably playing a role as a vector of resistance traits among the seawater bacterial population. However, the low transmission frequency of p3PS10 suggests a

  13. Genomic Microbial Epidemiology Is Needed to Comprehend the Global Problem of Antibiotic Resistance and to Improve Pathogen Diagnosis

    OpenAIRE

    Wyrsch, Ethan R.; Roy Chowdhury, Piklu; Chapman, Toni A.; Charles, Ian G.; Hammond, Jeffrey M.; Djordjevic, Steven P.

    2016-01-01

    Contamination of waste effluent from hospitals and intensive food animal production with antimicrobial residues is an immense global problem. Antimicrobial residues exert selection pressures that influence the acquisition of antimicrobial resistance and virulence genes in diverse microbial populations. Despite these concerns there is only a limited understanding of how antimicrobial residues contribute to the global problem of antimicrobial resistance. Furthermore, rapid detection of emerging...

  14. Microbial ecology, bacterial pathogens, and antibiotic resistant genes in swine manure as influenced by three swine management systems

    Science.gov (United States)

    The environmental influence of farm management in concentrated animal feeding operations (CAFO) can yield vastly different microbial constituents in both the pig and the manure lagoons used to treat the fecal waste of the operation. While some of these changes may not be negative, it is possible th...

  15. Variable virulence among isolates of Ascosphaera apis: testing the parasite-pathogen hypothesis for the evolution of polyandry in social insects

    Science.gov (United States)

    Lee, G. M.; McGee, P. A.; Oldroyd, B. P.

    2013-03-01

    The queens of many eusocial insect species are polyandrous. The evolution of polyandry from ancestral monoandry is intriguing because polyandry undermines the kin-selected benefits of high intracolonial relatedness that are understood to have been central to the evolution of eusociality. An accumulating body of evidence suggests that polyandry evolved from monoandry in part because genetically diverse colonies better resist infection by pathogens. However, a core assumption of the "parasite-pathogen hypothesis", that there is variation in virulence among strains of pathogens, remains largely untested in vivo. Here, we demonstrate variation in virulence among isolates of Ascosphaera apis, the causative organism of chalkbrood disease in its honey bee ( Apis mellifera) host. More importantly, we show a pathogen-host genotypic interaction for resistance and pathogenicity. Our findings therefore support the parasite-parasite hypothesis as a factor in the evolution of polyandry among eusocial insects.

  16. A simple and rapid immunochromatographic test strip for detection of pathogenic isolates of Vibrio harveyi.

    Science.gov (United States)

    Sithigorngul, Paisarn; Rukpratanporn, Sombat; Pecharaburanin, Nilawan; Suksawat, Pornthip; Longyant, Siwaporn; Chaivisuthangkura, Parin; Sithigorngul, Weerawan

    2007-12-01

    Mouse monoclonal antibodies (MAbs) and rabbit polyclonal antibody (PAb) against Vibrio harveyi were generated from immunization of mice and rabbits with highly virulent isolate of V. harveyi. Two MAbs specific to virulent isolates of V. harveyi were obtained and one of them (VH4) was selected to conjugate with colloidal gold as the detector antibody was laid on a sample pad. Rabbit polyclonal antibody was used as the capture antibody at the test line (T) and goat anti-mouse IgG antibody (GAM) was used as the capture antibody at the control line (C) of nitrocellulose strip. The ready-to-use strip was held in a plastic case and then stored in a desiccated plastic bag. A sample volume of 100 microl of bacterial suspension from various sources mixed with application buffer was applied to the sample chamber at one end of the strip and allowed to flow by chromatography through the nitrocellulose membrane to the other end. In test samples containing virulent isolates of V. harveyi, the bacteria would bind to the monoclonal antibody conjugated with colloidal gold and the resulting complex would be captured by the antibodies at the test line to give a reddish-purple band. Any unbound monoclonal antibody conjugated with colloidal gold moved across the test line would be captured by the GAM and form a band at the control line (C). In sample without V. harveyi or with V. harveyi below the limit (culture. The beneficial features of this kit are that simple, convenient and quick results (within 15 min) can be obtained without the requirement of sophisticated tools or special equipments and skills.

  17. Preliminary Evaluation of Microbial Communities Isolated from the Calcifying Fluid of Oysters

    Science.gov (United States)

    Banker, R.

    2016-02-01

    The process of biomineralization is defined as the selective uptake of elements that are incorporated into a defined mineral structure under strict biological control. For bivalve molluscs, such as clams, oysters, and mussels, the mantle is the primary organ in control of shell deposition. Alternatively, remote calcification takes place when carbonate-precipitating microbes (e.g. sulfate reducers) colonize a shell-secreting organism and enhance the ability of the host to build shell material. The oyster syndrome is a term that describes bivalves that possess an unusual shell morphology characterized by exceptionally thick valves containing numerous chambers filled with chalky calcite. Although remote calcification via microbial metabolism has been proposed as a mechanism of chalky deposit formation in oysters, this hypothesis has not yet been rigorously investigated. Here I present data on the microbial communities found in the calcifying fluid of two oyster species; Crassostrea gigas and Ostrea lurida are examples of oysters that do and do not exhibit the oyster syndrome, respectively. Comparison of the microbiomes of these two morphological end members may provide insight into the role of microbes in the formation of chalky deposits. Results indicate that the microbial community in the surrounding water is the dominant source for bacterial taxa found in the calcifying fluid of both oyster species. Also, it appears as though C. gigas maintains a microbial community that is more similar to its ambient environment than O. lurida. These results demonstrate that the ambient aquatic environment has a guiding influence on the microbiome found in the calcifying fluid of bivalve molluscs. However, the magnitude of this effect varies among organisms, even those that are closely related.

  18. Microbial population analysis of the salivary glands of ticks; a possible strategy for the surveillance of bacterial pathogens.

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    Yongjin Qiu

    Full Text Available Ticks are one of the most important blood-sucking vectors for infectious microorganisms in humans and animals. When feeding they inject saliva, containing microbes, into the host to facilitate the uptake of blood. An understanding of the microbial populations within their salivary glands would provide a valuable insight when evaluating the vectorial capacity of ticks. Three tick species (Ixodes ovatus, I. persulcatus and Haemaphysalis flava were collected in Shizuoka Prefecture of Japan between 2008 and 2011. Each tick was dissected and the salivary glands removed. Bacterial communities in each salivary gland were characterized by 16S amplicon pyrosequencing using a 454 GS-Junior Next Generation Sequencer. The Ribosomal Database Project (RDP Classifier was used to classify sequence reads at the genus level. The composition of the microbial populations of each tick species were assessed by principal component analysis (PCA using the Metagenomics RAST (MG-RAST metagenomic analysis tool. Rickettsia-specific PCR was used for the characterization of rickettsial species. Almost full length of 16S rDNA was amplified in order to characterize unclassified bacterial sequences obtained in I. persulcatus female samples. The numbers of bacterial genera identified for the tick species were 71 (I. ovatus, 127 (I. persulcatus and 59 (H. flava. Eighteen bacterial genera were commonly detected in all tick species. The predominant bacterial genus observed in all tick species was Coxiella. Spiroplasma was detected in Ixodes, and not in H. flava. PCA revealed that microbial populations in tick salivary glands were different between tick species, indicating that host specificities may play an important role in determining the microbial complement. Four female I. persulcatus samples contained a high abundance of several sequences belonging to Alphaproteobacteria symbionts. This study revealed the microbial populations within the salivary glands of three species of

  19. Establishment of a Pathogenicity Index for One-day-old Broilers to Pasteurella multocida Strains Isolated from Clinical Cases in Poultry and Swine

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    RM Pilatti

    Full Text Available ABSTRACT Although Pasteurella multocida is a member of the respiratory microbiota, under some circumstances, it is a primary agent of diseases , such as fowl cholera (FC, that cause significant economic losses. Experimental inoculations can be employed to evaluate the pathogenicity of strains, but the results are usually subjective and knowledge on the pathogenesis of this agent is still limited. The objective of this study was to establish a new methodology for classifying the pathogenicity of P. multocida by formulating a standard index. Strains isolated from FC cases and from swine with respiratory problems were selected. One hundred mL of a bacterial culture of each strain, containing 106 CFU, was inoculated in 10 one-day-old broilers. Mortality after inoculation, time of death (TD, and the presence of six macroscopic lesions were evaluated over a period of seven days post-inoculation (dpi. A Pathogenicity Index Per Bird (IPI, ranging 0 to 10, was calculated. Liver and heart fragments were collected to reisolate the bacteria. Blood was collected from the surviving birds, and an ELISA test was carried out to detect specific antibodies. The median of the pathogenicity indices, the number of lesions and the rate of bacteria reisolation were significantly different (p<0.05 among the origins of the isolates (p<0.05. The pathogenicity index developed in this study allows the classification of Pasteurella multocida pathogenicity and may be an alternative to the pathogenicity models currently used for screening.

  20. Characterization of Low Pathogenic Avian Influenza Virus Subtype H9N2 Isolated from Free-Living Mynah Birds (Acridotheres tristis) in the Sultanate of Oman.

    Science.gov (United States)

    Body, Mohammad H; Alrarawahi, Abdulmajeed H; Alhubsy, Saif S; Saravanan, Nirmala; Rajmony, Sunil; Mansoor, Muhammad Khalid

    2015-06-01

    A low pathogenic avian influenza virus was identified from free-living birds (mynah, Acridotheres tristis) of the starling family. Virus was isolated by inoculation of homogenized suspension from lung, tracheal, spleen, and cloacal swabs into the allantoic cavity of embryonated chicken eggs. Subtype of the isolate was characterized as H9N2 by hemagglutination inhibition test using monospecific chicken antisera to a wide range of influenza reference strain. Pathogenicity of the isolate was determined by intravenous pathogenicity index. The virus was reisolated from experimentally infected chicken. Additionally, the isolate was subjected to reverse transcriptase PCR using partial hemagglutinin (HA) gene-specific primers and yielded an amplicon of 487 bp. HA gene sequence analysis revealed 99% sequence homology among mynah and chicken isolates from Oman. On phylogenetic analysis, isolates from mynah (A/mynnah/Oman/AIVS6/2005) and chicken (A/chicken/Oman/AIVS3/2006; A/chicken/Oman/AIVS7/2006) clustered together tightly, indicating these free-flying birds may be a source of introduction of H9N2 subtype in poultry bird in Oman. Moreover, the HA gene of H9N2 isolates from Oman resembled those of viruses of the G1-like lineage and were very similar to those from United Arab Emirates.

  1. CT-Guided Biopsy in Suspected Spondylodiscitis--The Association of Paravertebral Inflammation with Microbial Pathogen Detection.

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    Daniel Spira

    Full Text Available To search for imaging characteristics distinguishing patients with successful from those with futile microbiological pathogen detection by CT-guided biopsy in suspected spondylodiscitis.34 consecutive patients with suspected spondylodiscitis underwent CT-guided biopsy for pathogen detection. MR-images were assessed for inflammatory infiltration of disks, adjacent vertebrae, epidural and paravertebral space. CT-images were reviewed for arrosion of adjacent end plates and reduced disk height. Biopsy samples were sent for microbiological examination in 34/34 patients, and for additional histological analysis in 28/34 patients.Paravertebral infiltration was present in all 10/10 patients with positive microbiology and occurred in only 12/24 patients with negative microbiology, resulting in a sensitivity of 100% and a specificity of 50% for pathogen detection. Despite its limited sensitivities, epidural infiltration and paravertebral abscesses showed considerably higher specificities of 83.3% and 90.9%, respectively. Paravertebral infiltration was more extensive in patients with positive as compared to negative microbiology (p = 0.002. Even though sensitivities for pathogen detection were also high in case of vertebral and disk infiltration, or end plate arrosion, specificities remained below 10%.Inflammatory infiltration of the paravertebral space indicated successful pathogen detection by CT-guided biopsy. Specificity was increased by the additional occurrence of epidural infiltration or paravertebral abscesses.

  2. The effect of lactic acid bacteria isolates on the urinary tract pathogens to infants in vitro.

    Science.gov (United States)

    Lim, In Seok; Lee, Ho Seok; Kim, Won Yong

    2009-01-01

    Urinary tract infections are common clinical problems in children, even though lots of treatment strategies have been tried. Many studies of the application of probiotics for urinary tract infection in female adults exist, but there is a lack of studies in children. The aims of this study were to screen probiotic strains for inhibiting the uropathogens in vitro, to find candidates for in vivo study. Nine strains of E. coli were isolated from children with urinary tract infection and six uropathogens were obtained from Korean Collection for Type Cultures and American Type Culture Collection. Also 135 lactic acid bacteria (LAB) strains were isolated from healthy children, and were identified through physiologic, biochemical methods, 16S rDNA PCR, and data analysis. And with agar disk diffusion assay technique the antimicrobial activities of these LAB strains against those uropathogens were examined. Three strains of separated LAB strains demonstrated major antimicrobial activity against all the uropathogens. In the agar disk diffusion assay technique, antimicrobial activities increased most in the 4th day culture broth with separated Lactobacillus. In summary, some LAB can be used as candidates to develop the probiotic microorganisms that inhibit uropathogens in children, and are expected to be applied to treatment and prevention of pediatric urinary tract infection.

  3. Interactions of microorganisms isolated from gilthead sea bream, Sparus aurata L., on Vibrio harveyi, a pathogen of farmed Senegalese sole, Solea senegalensis (Kaup).

    Science.gov (United States)

    Chabrillón, M; Rico, R M; Arijo, S; Díaz-Rosales, P; Balebona, M C; Moriñigo, M A

    2005-09-01

    Four bacterial isolates from farmed gilthead sea bream, Sparus aurata, included in a previous study as members of the Vibrionaceae and Pseudomonodaceae and the genus Micrococcus, have been evaluated for their adhesive ability to skin and intestinal mucus of farmed Senegalese sole, Solea senegalensis, and their antagonistic effect on Vibrio harveyi, a pathogen of sole. These isolates showed higher adhesion to sole mucus than the pathogenic strains of V. harveyi assayed. Only two of the isolates showed antagonistic activity to V. harveyi. Interactions of the four isolates with V. harveyi in respect of adhesion to skin and intestinal mucus under exclusion, competition and displacement conditions were studied. Three isolates were able to reduce the attachment to skin and intestinal sole mucus of a pathogenic strain of V. harveyi under displacement and exclusion conditions, but not under competition conditions. The in vivo probiotic potential of isolate Pdp11 was assessed by oral administration followed by challenge with the pathogenic V. harveyi strain Lg14/00. A group of 50 Senegalese sole received a commercial diet supplemented with 10(8) cfu g(-1) of lyophilized Lg14/00 for 15 days. A second group of fish received a non-supplemented commercial diet. After challenge the mortality of the fish receiving the diet supplemented with the potential probiotic isolate was significantly lower than that in the fish receiving the non-supplemented commercial diet. This study has shown that the ability to interfere with attachment of pathogens, as well as the adhesion to host surfaces, are suitable criteria for selection of candidate probiotics for use in the culture of Senegalese sole.

  4. Resistance among Gram-negative ESKAPE pathogens isolated from hospitalized patients with intra-abdominal and urinary tract infections in Latin American countries: SMART 2013–2015

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    James A. Karlowsky

    2017-05-01

    Full Text Available Gram-negative ESKAPE pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species are important etiologic agents of nosocomial infection that are frequently resistant to broad-spectrum antimicrobial agents. Gram-negative ESKAPE pathogens were collected from hospitalized patients in 11 Latin American countries from 2013 to 2015 as part of the Study for Monitoring Antimicrobial Resistance Trends (SMART global surveillance program. In total, 2113 isolates from intra-abdominal infections (IAI and 970 isolates from urinary tract infections (UTI were tested against antimicrobial agents using standardized CLSI broth microdilution methodology. Of the agents tested, amikacin demonstrated the highest rates of susceptibility (% for K. pneumoniae (92.2, 92.3, Enterobacter spp. (97.5, 92.1, and P. aeruginosa (85.3, 75.2 isolates from both IAI and UTI, respectively. Ertapenem (68.5, 62.6 and imipenem (79.2, 75.9 showed substantially higher rates of susceptibility (% than other β-lactams, including piperacillin-tazobactam (35.9, 37.4 against ESBL-positive isolates of K. pneumoniae from IAI and UTI, respectively. Rates of susceptibility to all agents tested against A. baumannii were ≤30.9%. Gram-negative ESKAPE pathogens isolated from Latin America demonstrated compromised in vitro susceptibility to commonly prescribed broad-spectrum, parenteral antimicrobial agents. Continued surveillance is warranted. New antimicrobial agents with potent activity against Gram-negative ESKAPE pathogens are urgently needed.

  5. Effect of temperature and humidity on pathogenicity of native Beauveria bassiana isolate against Musca domestica L.

    Science.gov (United States)

    Mishra, Sapna; Kumar, Peeyush; Malik, Anushree

    2015-12-01

    Beauveria bassiana HQ917687 virulence to housefly larvae and adult was assessed at different relative humidity, RH (50, 75, 90, and 100 %) and temperature (15, 20, 25, 30, 35, 40, 45 °C) conditions at the fungal dose of 10(8) conidia/ml. Depending on the temperature and RH regime tested, difference in mortality rates of housefly adult and larvae were detected. During assay on adult housefly, 100 % mortality was achieved at RH, 90 and 100 % while the temperature of 30 °C showed maximum mortality at all the tested humidity conditions. Lethal time, LT50 was 2.9 days at 100 % RH. Larval mortality at different humidity conditions varied between 30 and 74 %, with maximum mortality at 100 % RH and 30 °C. Optimum temperature for B. bassiana virulence to housefly larvae was also found to be 30 °C. The interaction between temperature and RH revealed significant effect of RH at moderate temperature range (20-35 °C), while such an interaction was not observed at extreme temperatures. The results obtained in this study have useful implications in understanding the pathogen behavior under actual field conditions. This in turn may help devising suitable entomopathogen release schedules for maximum fungal infection.

  6. Luminescence, virulence and quorum sensing signal production by pathogenic Vibrio campbellii and Vibrio harveyi isolates.

    Science.gov (United States)

    Defoirdt, T; Verstraete, W; Bossier, P

    2008-05-01

    To study the relationship between luminescence, autoinducer production and virulence of pathogenic vibrios. Luminescence, quorum sensing signal production and virulence towards brine shrimp nauplii of 13 Vibrio campbellii and Vibrio harveyi strains were studied. Although only two of the tested strains were brightly luminescent, all of them were shown to produce the three different types of quorum sensing signals known to be produced by Vibrio harveyi. Cell-free culture fluids of all strains significantly induced bioluminescence in the cholerae autoinducer 1, autoinducer 2 and harveyi autoinducer 1 reporter strains JAF375, JMH597 and JMH612, respectively. There was no relation between luminescence and signal production and virulence towards brine shrimp. There is a large difference between different strains of Vibrio campbellii and Vibrio harveyi with respect to bioluminescence. However, this is not reflected in signal production and virulence towards gnotobiotic brine shrimp. Moreover, there seems to be no relation between quorum sensing signal production and virulence towards brine shrimp. The results presented here indicate that strains that are most brightly luminescent are not necessarily the most virulent ones and that the lower virulence of some of the strains is not due to a lack of autoinducer production.

  7. Isolation, Characterization and Biological Properties of Membrane Vesicles Produced by the Swine Pathogen Streptococcus suis.

    Directory of Open Access Journals (Sweden)

    Bruno Haas

    Full Text Available Streptococcus suis, more particularly serotype 2, is a major swine pathogen and an emerging zoonotic agent worldwide that mainly causes meningitis, septicemia, endocarditis, and pneumonia. Although several potential virulence factors produced by S. suis have been identified in the last decade, the pathogenesis of S. suis infections is still not fully understood. In the present study, we showed that S. suis produces membrane vesicles (MVs that range in diameter from 13 to 130 nm and that appear to be coated by capsular material. A proteomic analysis of the MVs revealed that they contain 46 proteins, 9 of which are considered as proven or suspected virulence factors. Biological assays confirmed that S. suis MVs possess active subtilisin-like protease (SspA and DNase (SsnA. S. suis MVs degraded neutrophil extracellular traps, a property that may contribute to the ability of the bacterium to escape the host defense response. MVs also activated the nuclear factor-kappa B (NF-κB signaling pathway in both monocytes and macrophages, inducing the secretion of pro-inflammatory cytokines, which may in turn contribute to increase the permeability of the blood brain barrier. The present study brought evidence that S. suis MVs may play a role as a virulence factor in the pathogenesis of S. suis infections, and given their composition be an excellent candidate for vaccine development.

  8. Genetic characterization of highly pathogenic avian influenza A H5N8 viruses isolated from wild birds in Egypt.

    Science.gov (United States)

    Kandeil, Ahmed; Kayed, Ahmed; Moatasim, Yassmin; Webby, Richard J; McKenzie, Pamela P; Kayali, Ghazi; Ali, Mohamed A

    2017-07-01

    A newly emerged H5N8 influenza virus was isolated from green-winged teal in Egypt during December 2016. In this study, we provide a detailed characterization of full genomes of Egyptian H5N8 viruses and some virological features. Genetic analysis demonstrated that the Egyptian H5N8 viruses are highly pathogenic avian influenza viruses. Phylogenetic analysis revealed that the genome of the Egyptian H5N8 viruses was related to recently characterized reassortant H5N8 viruses of clade 2.3.4.4 isolated from different Eurasian countries. Multiple peculiar mutations were characterized in the Egyptian H5N8 viruses, which probably permits transmission and virulence of these viruses in mammals. The Egyptian H5N8 viruses preferentially bound to avian-like receptors rather than human-like receptors. Also, the Egyptian H5N8 viruses were fully sensitive to amantadine and neuraminidase inhibitors. Chicken sera raised against commercial inactivated avian influenza-H5 vaccines showed no or very low reactivity with the currently characterized H5N8 viruses in agreement with the genetic dissimilarity. Surveillance of avian influenza in waterfowl provides early warning of specific threats to poultry and human health and hence should be continued.

  9. Purification of a toxic metalloprotease produced by the pathogenic Photobacterium damselae subsp. piscicida isolated from cobia (Rachycentron canadum).

    Science.gov (United States)

    Liu, Ping-Chung; Chuang, Wen-Hsiao; Lee, Kuo-Kau

    2011-01-01

    The aim of the present study was to purify and characterize a toxic protease secreted by the pathogenic Photobacterium damselae subsp. piscicida strain CP1 originally isolated from diseased cobia (Rachycentron canadum). The toxin isolated by anion exchange chromatography, was a metalloprotease, inhibited by L-cysteine, ethylenediaminetetraacetic acid (EDTA), ethylene glycol-bis(beta-aminoethyl ether)N,N,N',N'-tetraacetic acid (EGTA), 1,10-phenanthroline, N-tosyl-L-phenylalanine-chloromethyl ketone (TPCK), and N-alpha-p-tosyl-L-lysine-chloromethyl ketone (TLCK), and showed maximal activity at pH 6.0-8.0 and an apparent molecular mass of about 34.3 kDa. The toxin was also completely inhibited by HgCl2, and partially by sodium dodecyl sulfate (SDS) and CuCl2. The extracellular products and the partially purified protease were lethal to cobia with LD50 values of 1.26 and 6.8 microg protein/g body weight, respectively. The addition of EDTA completely inhibited the lethal toxicity of the purified protease, indicating that this metalloprotease was a lethal toxin produced by the bacterium.

  10. Molecular characterization of bacteria isolated from the Kingdom of ...

    African Journals Online (AJOL)

    ola

    2012-11-06

    Nov 6, 2012 ... Esherichia coli strains isolated from different habitats in relation to their antimicrobial activity against pathogenic fungi causing dermatological diseases. MATERIALS AND METHODS. Microbial strains, media and culture conditions. Bacterial isolates from soil samples were collected from different localities ...

  11. Antibiotic resistance profile of Escherichia coli isolated from five ...

    African Journals Online (AJOL)

    Information on the resistance profiles of clinical and non clinical human bacteria isolates in the developing countries can serve as important means of understanding the human pathogens drug resistance interactions in the zone. Escherichia coli isolated from five geopolitical zones of Nigeria were screened for anti-microbial ...

  12. Microbial safety of foods

    International Nuclear Information System (INIS)

    Bandekar, J.R.

    2013-01-01

    Despite advances in hygiene, consumer knowledge and food treatment and processing, food-borne diseases have become one of the most widespread public health problems in the world to-day. About two thirds of all outbreaks are traced to microbial contaminated food - one of the most hazardous being Clostridium botulinum, E. coli 0157: H7 and Salmonella. The pathogens can be introduced in the food products anywhere in the food chain and hence it is of prime important to have microbial vigilance in the entire food chain. WHO estimates that food-borne and water-borne diarrhoeal diseases taken together kill about 2.2 million people annually. The infants, children, elderly and immune-compromised people are particularly susceptible to food-borne diseases. Unsafe food causes many acute and life-long diseases, ranging from diarrhoeal diseases to various forms of cancer. A number of factors such as emergence of new food-borne pathogens, development of drug resistance in the pathogens, changing life style, global trade of food etc. are responsible for the continued persistence of food-borne diseases. Due to consumer demand, a number of Ready-To-Eat (RTE) minimally processed foods are increasingly marketed. However, there is increased risk of food-borne diseases with these products. The food-borne disease outbreaks due to E. coli O157:H7, Listeria monocytogenes, Salmonella and Campylobacter are responsible for recall of many foods resulting in heavy losses to food industry. The development of multi drug resistant pathogens due to indiscriminate use of antibiotics is also a major problem. Food Technology Division of Bhabha Atomic Research Centre has been working on food-borne bacterial pathogens particularly Salmonella, Campylobacter, Vibrio and Aeromonas species, their prevalence in export quality seafood as well in foods sold in retail market such as poultry, fish, sprouts and salads. These pathogens from Indian foods have been characterized for the presence of virulence genes

  13. MICROBIAL PROFILE AND ANTIBIOTIC RESISTANCE PATTERN OF THE BACTERIAL ISOLATES IN A TERTIARY CARE PSYCHIATRY HOSPITAL

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    Jyoti

    2015-11-01

    Full Text Available BACKGROUND: Antibiotic resistance is a challenge for effective management of infections as it increases the morbidity, mortality and costs of treating infectious diseases. AIMS: This study was aimed to obtain the profile of the bacterial isolates and their antibiotic resistance pattern. SETTINGS AND DESIGN: It is a cross sectional study carried out in a tertiary care psychiatry hospital in India. MATERIALS AND METHODS: Isolation and identification of the isolates were done by standard methods. Susceptibility patterns were checked by Kirby Bauer disc diffusion method. STATISTICAL ANALYSIS USED: Statistical analysis was done by using SPSS 16.0 version to calculate the frequencies as well as for cross tabulation. RESULTS: Significant bacterial growth observed in 43(25.6% samples, of which 39(90.7% showed resistant to at least one of the antibiotics used and 36(83.7% were multi-drug resistant. Gram negative organism accounted for the 25(58.14% of total significant isolates, Escherichia coli being the highest (76% in this group. Among multi-drug resistant (MDR isolates E.coli was the highest (44.4% and imipenem resistance was also observed in 1(5.3% of 19 E.coli isolates. Among the 43 isolates 18(41.86% were Gram positive with Streptococcus spp. showing incidence of 41.7% among the total MDR isolates. CONCLUSION: Increasing incidence of MDR strains seen in the population requires continuous monitoring and a restricted use of antibiotics to keep a check on resistance pattern, for effective treatment plan.

  14. The inhibitory effect of Mesembryanthemum edule (L.) bolus essential oil on some pathogenic fungal isolates

    Science.gov (United States)

    2014-01-01

    Background Mesembryanthemum edule is a medicinal plant which has been indicated by Xhosa traditional healers in the treatment HIV associated diseases such as tuberculosis, dysentery, diabetic mellitus, laryngitis, mouth infections, ringworm eczema and vaginal infections. The investigation of the essential oil of this plant could help to verify the rationale behind the use of the plant as a cure for these illnesses. Methods The essential oil from M. edule was analysed by GC/MS. Concentration ranging from 0.005 - 5 mg/ml of the hydro-distilled essential oil was tested against some fungal strains, using micro-dilution method. The plant minimum inhibitory activity on the fungal strains was determined. Result GC/MS analysis of the essential oil resulted in the identification of 28 compounds representing 99.99% of the total essential oil. A total amount of 10.6 and 36.61% constituents were obtained as monoterpenes and oxygenated monoterpenes. The amount of sesquiterpene hydrocarbons (3.58%) was low compared to the oxygenated sesquiterpenes with pick area of 9.28%. Total oil content of diterpenes and oxygenated diterpenes detected from the essential oil were 1.43% and 19.24%. The fatty acids and their methyl esters content present in the essential oil extract were found to be 19.25%. Antifungal activity of the essential oil extract tested against the pathogenic fungal, inhibited C. albican, C. krusei, C. rugosa, C. glabrata and C. neoformans with MICs range of 0.02-0.31 mg/ml. the activity of the essential oil was found competing with nystatin and amphotericin B used as control. Conclusion Having accounted the profile chemical constituent found in M. edule oil and its important antifungal properties, we consider that its essential oil might be useful in pharmaceutical and food industry as natural antibiotic and food preservative. PMID:24885234

  15. Haemophilus influenzae Isolated From Men With Acute Urethritis: Its Pathogenic Roles, Responses to Antimicrobial Chemotherapies, and Antimicrobial Susceptibilities.

    Science.gov (United States)

    Ito, Shin; Hatazaki, Kyoko; Shimuta, Ken; Kondo, Hiromi; Mizutani, Kosuke; Yasuda, Mitsuru; Nakane, Keita; Tsuchiya, Tomohiro; Yokoi, Shigeaki; Nakano, Masahiro; Ohinishi, Makoto; Deguchi, Takashi

    2017-04-01

    There have been few comprehensive studies on Haemophilus influenza-positive urethritis. In this retrospective study, we enrolled 68 men with H. influenzae-positive urethritis, including coinfections with Neisseria gonorrhoeae, Chlamydia trachomatis, and/or genital mycoplasmas: 2, 3, 20, and 43 treated with ceftriaxone, levofloxacin, sitafloxacin, and extended-release azithromycin (azithromycin-SR), respectively. We assessed microbiological outcomes in 54 men and clinical outcomes in 46 with H. influenzae-positive monomicrobial nongonococcal urethritis. We determined minimum inhibitory concentrations (MICs) of 6 antimicrobial agents for 59 pretreatment isolates. H. influenzae was eradicated from the men treated with ceftriaxone, levofloxacin, or sitafloxacin. The eradication rate with azithromycin-SR was 85.3%. The disappearance or alleviation of urethritis symptoms and the decreases in leukocyte counts in first-voided urine were significantly associated with the eradication of H. influenzae after treatment. For the isolates, ceftriaxone, levofloxacin, sitafloxacin, azithromycin, tetracycline, and doxycycline MICs were ≤0.008-0.25, 0.008-0.5, 0.001-0.008, 0.12-1, 0.25-16, and 0.25-2 μg/mL, respectively. The azithromycin MICs for 3 of 4 strains persisting after azithromycin-SR administration were 1 μg/mL. H. influenzae with an azithromycin MIC of 1 μg/mL increased chronologically. H. influenzae showed good responses to the chemotherapies for urethritis. The significant associations of the clinical outcomes of the chemotherapies with their microbiological outcomes suggested that H. influenzae could play pathogenic roles in urethritis. All isolates, except for one with decreased susceptibility to tetracyclines, were susceptible to the examined agents. However, the increase in H. influenzae with an azithromycin MIC of 1 μg/mL might threaten efficacies of azithromycin regimens on H. influenzae-positive urethritis.

  16. Low pathogenic avian influenza isolates from wild birds replicate and transmit via contact in ferrets without prior adaptation.

    Science.gov (United States)

    Driskell, Elizabeth A; Pickens, Jennifer A; Humberd-Smith, Jennifer; Gordy, James T; Bradley, Konrad C; Steinhauer, David A; Berghaus, Roy D; Stallknecht, David E; Howerth, Elizabeth W; Tompkins, Stephen Mark

    2012-01-01

    Direct transmission of avian influenza viruses to mammals has become an increasingly investigated topic during the past decade; however, isolates that have been primarily investigated are typically ones originating from human or poultry outbreaks. Currently there is minimal comparative information on the behavior of the innumerable viruses that exist in the natural wild bird host. We have previously demonstrated the capacity of numerous North American avian influenza viruses isolated from wild birds to infect and induce lesions in the respiratory tract of mice. In this study, two isolates from shorebirds that were previously examined in mice (H1N9 and H6N1 subtypes) are further examined through experimental inoculations in the ferret with analysis of viral shedding, histopathology, and antigen localization via immunohistochemistry to elucidate pathogenicity and transmission of these viruses. Using sequence analysis and glycan binding analysis, we show that these avian viruses have the typical avian influenza binding pattern, with affinity for cell glycoproteins/glycolipids having terminal sialic acid (SA) residues with α 2,3 linkage [Neu5Ac(α2,3)Gal]. Despite the lack of α2,6 linked SA binding, these AIVs productively infected both the upper and lower respiratory tract of ferrets, resulting in nasal viral shedding and pulmonary lesions with minimal morbidity. Moreover, we show that one of the viruses is able to transmit to ferrets via direct contact, despite its binding affinity for α 2,3 linked SA residues. These results demonstrate that avian influenza viruses, which are endemic in aquatic birds, can potentially infect humans and other mammals without adaptation. Finally this work highlights the need for additional study of the wild bird subset of influenza viruses in regard to surveillance, transmission, and potential for reassortment, as they have zoonotic potential.

  17. Quantification of disease progression of several microbial pathogens on Arabidopsis thaliana using real-time fluorescence PCR

    NARCIS (Netherlands)

    Brouwer, M.; Lievens, B.; Hemelrijck, van W.; Ackerveken, van den G.; Cammue, B.P.A.; Thomma, B.P.H.J.

    2003-01-01

    An accurate monitoring of disease progression is important to evaluate disease susceptibility phenotypes. Over the years, Arabidopsis thaliana has become the model species to serve as a host in plant-pathogen interactions. Despite the efforts to study genetic mechanisms of host defense, little

  18. Approaches for Reverse Line Blot-Based Detection of Microbial Pathogens in Ixodes ricinus Ticks Collected in Austria and Impact of the Chosen Method.

    Science.gov (United States)

    Schötta, Anna-Margarita; Wijnveld, Michiel; Stockinger, Hannes; Stanek, Gerold

    2017-07-01

    Ticks transmit a large number of pathogens capable of causing human disease. In this study, the PCR-reverse line blot (RLB) method was used to screen for pathogens in a total of 554 Ixodes ricinus ticks collected from all provinces of Austria. These pathogens belong to the genera Borrelia , Rickettsiae , Anaplasma / Ehrlichia (including " Candidatus Neoehrlichia"), Babesia , and Coxiella The pathogens with the highest detected prevalence were spirochetes of the Borrelia burgdorferi sensu lato complex, in 142 ticks (25.6%). Borrelia afzelii (80/142) was the most frequently detected species, followed by Borrelia burgdorferi sensu stricto (38/142) and Borrelia valaisiana (36/142). Borrelia garinii/Borrelia bavariensis , Borrelia lusitaniae , and Borrelia spielmanii were found in 28 ticks, 5 ticks, and 1 tick, respectively. Rickettsia spp. were detected in 93 ticks (16.8%): R. helvetica (39/93), R. raoultii (38/93), R. monacensis (2/93), and R. slovaca (1/93). Thirteen Rickettsia samples remain uncharacterized. " Candidatus Neoehrlichia mikurensis," Babesia spp. ( B. venatorum , B. divergens , B. microti ), and Anaplasma phagocytophilum were found in 4.5%, 2.7%, and 0.7%, respectively. Coxiella burnetii was not detected. Multiple microorganisms were detected in 40 ticks (7.2%), and the cooccurrence of Babesia spp. and " Candidatus Neoehrlichia mikurensis" showed a significant positive correlation. We also compared different PCR-RLBs for detection of Borrelia burgdorferi sensu lato and Rickettsia spp. and showed that different detection approaches provide highly diverse results, indicating that analysis of environmental samples remains challenging. IMPORTANCE This study determined the wide spectrum of tick-borne bacterial and protozoal pathogens that can be encountered in Austria. Surveillance of (putative) pathogenic microorganisms occurring in the environment is of medical importance, especially when those agents can be transmitted by ticks and cause disease. The

  19. Direct cloning from enrichment cultures, a reliable strategy for isolation of complete operons and genes from microbial consortia.

    Science.gov (United States)

    Entcheva, P; Liebl, W; Johann, A; Hartsch, T; Streit, W R

    2001-01-01

    Enrichment cultures of microbial consortia enable the diverse metabolic and catabolic activities of these populations to be studied on a molecular level and to be explored as potential sources for biotechnology processes. We have used a combined approach of enrichment culture and direct cloning to construct cosmid libraries with large (>30-kb) inserts from microbial consortia. Enrichment cultures were inoculated with samples from five environments, and high amounts of avidin were added to the cultures to favor growth of biotin-producing microbes. DNA was extracted from three of these enrichment cultures and used to construct cosmid libraries; each library consisted of between 6,000 and 35,000 clones, with an average insert size of 30 to 40 kb. The inserts contained a diverse population of genomic DNA fragments isolated from the consortia organisms. These three libraries were used to complement the Escherichia coli biotin auxotrophic strain ATCC 33767 Delta(bio-uvrB). Initial screens resulted in the isolation of seven different complementing cosmid clones, carrying biotin biosynthesis operons. Biotin biosynthesis capabilities and growth under defined conditions of four of these clones were studied. Biotin measured in the different culture supernatants ranged from 42 to 3,800 pg/ml/optical density unit. Sequencing the identified biotin synthesis genes revealed high similarities to bio operons from gram-negative bacteria. In addition, random sequencing identified other interesting open reading frames, as well as two operons, the histidine utilization operon (hut), and the cluster of genes involved in biosynthesis of molybdopterin cofactors in bacteria (moaABCDE).

  20. Dehydro-alpha-lapachone isolated from Catalpa ovata stems: activity against plant pathogenic fungi.

    Science.gov (United States)

    Cho, Jun Young; Kim, Hae Young; Choi, Gyung Ja; Jang, Kyoung Soo; Lim, He Kyoung; Lim, Chi Hwan; Cho, Kwang Yun; Kim, Jin-Cheol

    2006-05-01

    The methanol extract of stems of Catalpa ovata G Don exhibits potent in vivo antifungal activity against Magnaporthe grisea (Hebert) Barr (rice blast) on rice plants, Botrytis cinerea Pers ex Fr (tomato grey mould) and Phytophthora infestans (Mont) de Bary (tomato late blight) on tomato plants, Puccinia recondita Rob ex Desm (wheat leaf rust) on wheat plants and Blumeria graminis (DC) Speer f. sp. hordei Marchal (barley powdery mildew) on barley plants. An antifungal substance was isolated and identified as dehydro-alpha-lapachone from mass and nuclear magnetic resonance spectral data. It completely inhibited the mycelial growth of B. cinerea, Colletotrichum acutatum Simmonds, Colletotrichum gloeosporioides Simmonds, M. grisea and Pythium ultimum Trow over a range of 0.4-33.3 mg litre(-1). It also controlled the development of rice blast, tomato late blight, wheat leaf rust, barley powdery mildew and red pepper anthracnose (Colletotrichum coccodes (Wallr) S Hughes). The chemical was particularly effective in suppressing red pepper anthracnose by 95% at a concentration of 125 mg litre(-1). Copyright 2006 Society of Chemical Industry.

  1. Characterization of H5N6 highly pathogenic avian influenza viruses isolated from wild and captive birds in the winter season of 2016-2017 in Northern Japan.

    Science.gov (United States)

    Hiono, Takahiro; Okamatsu, Masatoshi; Matsuno, Keita; Haga, Atsushi; Iwata, Ritsuko; Nguyen, Lam Thanh; Suzuki, Mizuho; Kikutani, Yuto; Kida, Hiroshi; Onuma, Manabu; Sakoda, Yoshihiro

    2017-09-01

    On 15 November 2016, a black swan that had died in a zoo in Akita prefecture, northern Japan, was strongly suspected to have highly pathogenic avian influenza (HPAI); an HPAI virus (HPAIV) belonging to the H5N6 subtype was isolated from specimens taken from the bird. After the initial report, 230 cases of HPAI caused by H5N6 viruses from wild birds, captive birds, and domestic poultry farms were reported throughout the country during the winter season. In the present study, 66 H5N6 HPAIVs isolated from northern Japan were further characterized. Phylogenetic analysis of the hemagglutinin gene showed that the H5N6 viruses isolated in northern Japan clustered into Group C of Clade 2.3.4.4 together with other isolates collected in Japan, Korea and Taiwan during the winter season of 2016-2017. The antigenicity of the Japanese H5N6 isolate differed slightly from that of HPAIVs isolated previously in Japan and China. The virus exhibited high pathogenicity and a high replication capacity in chickens, whereas virus growth was slightly lower in ducks compared with that of an H5N8 HPAIV isolate collected in Japan in 2014. Comprehensive analyses of Japanese isolates, including those from central, western, and southern Japan, as well as rapid publication of this information are essential for facilitating greater control of HPAIVs. © 2017 The Societies and John Wiley & Sons Australia, Ltd.

  2. Identification of microbial isolates from vacuum-packaged ground pork irradiated at 1 kGy

    International Nuclear Information System (INIS)

    Ehioba, R.M.; Kraft, A.A.; Molins, R.A.; Walker, H.W.; Olson, D.G.; Subbaraman, G.; Skowronski, R.P.

    1988-01-01

    Bacterial cultures from irradiated (1 kGy) and nonirradiated, vacuum-packaged ground pork held at 5 0 C were isolated and characterized over a 12-day storage period. The initial flora of the meat was composed mostly of Pseudomonas sp., and Enterobacter sp. Although the microflora of nonirradiated samples gradually shifted from Gram-negative to Gram-positive microorganisms, 76% of the isolates were characterized as Gram-negative at the onset of spoilage (9 days at 5 0 C). In contrast, the irradiated ground pork microflora was mainly Gram-positive (66%) shortly after irradiation and increased to 97% after 9 days at 5 0 C. A total of 720 isolates were identified to genus

  3. Draft Genome Sequence of Rhizobium sp. Strain TBD182, an Antagonist of the Plant-Pathogenic Fungus Fusarium oxysporum, Isolated from a Novel Hydroponics System Using Organic Fertilizer.

    Science.gov (United States)

    Iida, Yuichiro; Fujiwara, Kazuki; Someya, Nobutaka; Shinohara, Makoto

    2017-03-16

    Rhizobium sp. strain TBD182, isolated from a novel hydroponics system, is an antagonistic bacterium that inhibits the mycelial growth of Fusarium oxysporum but does not eliminate the pathogen. We report the draft genome sequence of TBD182, which may contribute to elucidation of the molecular mechanisms of its fungistatic activity. Copyright © 2017 Iida et al.

  4. The potential pathogenicity of chlorhexidine-sensitive Acanthamoeba strains isolated from contact lens cases from asymptomatic individuals in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Martín-Navarro, Carmen M; Lorenzo-Morales, Jacob; Cabrera-Serra, M Gabriela; Rancel, Fernando; Coronado-Alvarez, Nieves M; Piñero, José E; Valladares, Basilio

    2008-11-01

    Pathogenic strains of the genus Acanthamoeba are causative agents of a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. The prevalence of this infection has risen in the past 20 years, mainly due to the increase in number of contact lens wearers. In this study, the prevalence of Acanthamoeba in a risk group constituted by asymptomatic contact lens wearers from Tenerife, Canary Islands, Spain, was evaluated. Contact lenses and contact lens cases were analysed for the presence of Acanthamoeba isolates. The isolates' genotypes were also determined after rDNA sequencing. The pathogenic potential of the isolated strains was subsequently established using previously described molecular and biochemical assays, which allowed the selection of three strains with high pathogenic potential. Furthermore, the sensitivity of these isolates against two standard drugs, ciprofloxacin and chlorhexidine, was analysed. As the three selected strains were sensitive to chlorhexidine, its activity and IC(50) were evaluated. Chlorhexidine was found to be active against these strains and the obtained IC(50) values were compared to the concentrations of this drug present in contact lens maintenance solutions. It was observed that the measured IC(50) was higher than the concentration found in these maintenance solutions. Therefore, the ineffectiveness of chlorhexidine-containing contact lens maintenance solutions against potentially pathogenic strains of Acanthamoeba is demonstrated in this study.

  5. Compost as a source of microbial isolates for the bioremediation of heavy metals: In vitro selection

    International Nuclear Information System (INIS)

    Vargas-García, María del Carmen; López, María José; Suárez-Estrella, Francisca; Moreno, Joaquín

    2012-01-01

    Heavy metal pollution has become a major environmental concern nowadays and the bioremediation of polluted habitats is an increasingly popular strategy due to both its efficiency and safety. A screening and selection protocol based on different composting processes was designed in order to isolate heavy metal-resistant microorganisms. A collection of 51 microorganisms was obtained and most of them showed the capability to tolerate heavy metals in multi-polluted aqueous systems (Cd(II), Cr(VI), Ni, Pb, Zn(II)), as well as to remove them. The highest detoxification ratios were observed for Pb. Some of the isolates detoxifying more than a 90% of this metal, while the other metals were removed in a range between 20% and 60%. The best isolates (Graphium putredinis, Fusarium solani, Fusarium sp. and Penicillium chrysogenum) were further assayed in order to determine the predominant removal mechanism and the potential use of their dead biomass as a biosorbent. Intracellular accumulation was the prevalent mechanism for most isolates and metals, with the exception of Ni. In this case, the proportion removed by extracellular adsorption was similar or even higher than that removed by intracellular accumulation. Thus, the efficiency of living cells was higher than that of dead biomass except in the case of Ni. - Highlights: ► Composting is a good reservoir for the isolation of HM-resistant microorganisms. ► Pb was the most removed heavy metal in multi-polluted aqueous systems. ► Intracellular accumulation was the predominant mechanism for heavy metal removal. ► Graphium putredinis, which detoxifies organic pollutants, was the most efficient isolate.

  6. Compost as a source of microbial isolates for the bioremediation of heavy metals: In vitro selection

    Energy Technology Data Exchange (ETDEWEB)

    Vargas-Garcia, Maria del Carmen, E-mail: mcvargas@ual.es; Lopez, Maria Jose, E-mail: mllopez@ual.es; Suarez-Estrella, Francisca, E-mail: fsuarez@ual.es; Moreno, Joaquin, E-mail: jcasco@ual.es

    2012-08-01

    Heavy metal pollution has become a major environmental concern nowadays and the bioremediation of polluted habitats is an increasingly popular strategy due to both its efficiency and safety. A screening and selection protocol based on different composting processes was designed in order to isolate heavy metal-resistant microorganisms. A collection of 51 microorganisms was obtained and most of them showed the capability to tolerate heavy metals in multi-polluted aqueous systems (Cd(II), Cr(VI), Ni, Pb, Zn(II)), as well as to remove them. The highest detoxification ratios were observed for Pb. Some of the isolates detoxifying more than a 90% of this metal, while the other metals were removed in a range between 20% and 60%. The best isolates (Graphium putredinis, Fusarium solani, Fusarium sp. and Penicillium chrysogenum) were further assayed in order to determine the predominant removal mechanism and the potential use of their dead biomass as a biosorbent. Intracellular accumulation was the prevalent mechanism for most isolates and metals, with the exception of Ni. In this case, the proportion removed by extracellular adsorption was similar or even higher than that removed by intracellular accumulation. Thus, the efficiency of living cells was higher than that of dead biomass except in the case of Ni. - Highlights: Black-Right-Pointing-Pointer Composting is a good reservoir for the isolation of HM-resistant microorganisms. Black-Right-Pointing-Pointer Pb was the most removed heavy metal in multi-polluted aqueous systems. Black-Right-Pointing-Pointer Intracellular accumulation was the predominant mechanism for heavy metal removal. Black-Right-Pointing-Pointer Graphium putredinis, which detoxifies organic pollutants, was the most efficient isolate.

  7. The analysis of milk components and pathogenic bacteria isolated from bovine raw milk in Korea.

    Science.gov (United States)

    Park, Y K; Koo, H C; Kim, S H; Hwang, S Y; Jung, W K; Kim, J M; Shin, S; Kim, R T; Park, Y H

    2007-12-01

    Bovine mastitis can be diagnosed by abnormalities in milk components and somatic cell count (SCC), as well as by clinical signs. We examined raw milk in Korea by analyzing SCC, milk urea nitrogen (MUN), and the percentages of milk components (milk fat, protein, and lactose). The associations between SCC or MUN and other milk components were investigated, as well as the relationships between the bacterial species isolated from milk. Somatic cell counts, MUN, and the percentages of milk fat, protein, and lactose were analyzed in 30,019 raw milk samples collected from 2003 to 2006. The regression coefficients of natural logarithmic-transformed SCC (SCCt) on milk fat (-0.0149), lactose (-0.8910), and MUN (-0.0096), and those of MUN on milk fat (-0.3125), protein (-0.8012), and SCCt (-0.0671) were negative, whereas the regression coefficient of SCCt on protein was positive (0.3023). When the data were categorized by the presence or absence of bacterial infection in raw milk, SCCt was negatively associated with milk fat (-0.0172), protein (-0.2693), and lactose (-0.4108). The SCCt values were significantly affected by bacterial species. In particular, 104 milk samples infected with Staphylococcus aureus had the highest SCCt (1.67) compared with milk containing other mastitis-causing bacteria: coagulase-negative staphylococci (n = 755, 1.50), coagulase-positive staphylococci (except Staphylococcus aureus; n = 77, 1.59), Streptococcus spp. (Streptococcus dysgalactiae, n = 37; Streptococcus uberis, n = 12, 0.83), Enterococcus spp. (n = 46, 1.04), Escherichia coli (n = 705, 1.56), Pseudomonas spp. (n = 456, 1.59), and yeast (n = 189, 1.52). These results show that high SCC and MUN negatively affect milk components and that a statistical approach associating SCC, MUN, and milk components by bacterial infection can explain the patterns among them. Bacterial species present in raw milk are an important influence on SCC in Korea.

  8. Anti - microbial resistance stratified by risk factor among Escherichia coli strains isolated from the urinary tract at a rural clinic in Central India

    Directory of Open Access Journals (Sweden)

    Chatterjee B

    2009-01-01

    Full Text Available Background: The failure of empirical therapy is frequently observed, even in community-acquired urinary tract infections. We, therefore, conducted a prospective, clinic-based study in 2004-2005 to document anti-microbial resistance rates and correlate them with possible risk factors to assist empirical decision-making. Materials and Methods: Symptomatic patients with pyuria underwent urine culture. Isolates were identified using standard methods and anti-microbial resistance was determined by disk-diffusion. Ultrasonography was used to detect complicating factors. Patients were stratified by the presence of complicating factors and history of invasive procedures for comparison of resistance rates. Statistical Method Used: Chi-square or Fisher exact tests, as appropriate. Results: There were 156 E. coli isolates, of which 105 were community-acquired. Twenty-three community-acquired isolates were from patients with complicating factors while 82 were from patients without any. Fifty-one isolates were from patients who had recently undergone invasive procedures on the urinary tract. Thirty-two community-acquired isolates from reproductive-age women without apparent complicating factors had resistance rates of 50% or above against tetracyclines, Co-trimoxazole, aminopenicillins, Nalidixic acid, Ciprofloxacin and 1 st generation cephalosporins. Resistance rates were significantly higher among isolates from patients subjected to invasive procedures, except against Co-trimoxazole, tetracyclines and Amikacin. Conclusion: High rates of anti-microbial resistance in community-acquired uropathogens have made antimicrobial sensitivity testing necessary even in a rural, primary-care setting.

  9. A novel photo-biological engineering method for Salvia miltiorrhiza-mediated fabrication of silver nanoparticles using LED lights sources and its effectiveness against Aedes aegypti mosquito larvae and microbial pathogens

    Science.gov (United States)

    In this study, Salvia miltiorrhiza-synthesized Ag nanoparticles (AgNPs) fabricated using sunlight or various LED lights were studied for their biophysical features and evaluated as larvicides against Aedes aegypti mosquitoes and growth inhibitors on different species of microbial pathogens. AgNPs pr...

  10. The Effectiveness Evaluation of Current Disinfectants on Pathogens Isolated from Surface of Different Parts of Shahid Sadughi Accidents Burns Hospital in City of Yazd

    Directory of Open Access Journals (Sweden)

    Fatemeh Sahlabadi

    2016-03-01

    Full Text Available Background: The burn unit is a suitable environment for the growth of pathogenic bacteria that can reduce these pathogens by appropriate disinfection methods. So, choosing an appropriate disinfectant and applying standard methods of disinfection can be effective in reducing nosocomial infections. The aim of this study is evaluation of efficacy of current disinfectants on pathogens isolated from surface of different parts of Shahid Sadughi accidents burns hospital in city of Yazd. Methods: In this study, the sampling method has done simple randomly and 240 samples were collected from 30 different parts of hospital surfaces (for every disinfectant 30 samples before and 30 samples after disinfection. The samples in the Microbiology laboratory of Medical Sciences University were cultured on blood agar and EMB agar culture. Colonies that were suspected to pathogens were identified by biochemical tests and their colony count was determined. Data were analyzed using Paired T-test. Results: The average of isolated bacteria at 4 parts of burn unit of hospital before disinfecting by Deconex 50 AF, Descoscid, Epimax SC and Silvosept was 58.02, 18897.28, 30989.05 and 38.52 respectively and after disinfecting was 12.8, 0.62, 1.65 and 5.09 respectively. Reducing of contamination in all disinfectants shown a significant difference (p<0.05. The most common isolated pathogens were Pseudomonas aeruginosa, Klebsiella, staphylococcus aureus, Enterobacter and Escherichia coli. Conclusion: The results showed that all disinfectants was effective on isolated pathogens and also have shown a significant difference (p<0.05 between the average of bacteria count before and after disinfection.

  11. Frequent combination of antimicrobial multiresistance and extraintestinal pathogenicity in Escherichia coli isolates from urban rats (Rattus norvegicus in Berlin, Germany.

    Directory of Open Access Journals (Sweden)

    Sebastian Guenther

    Full Text Available Urban rats present a global public health concern as they are considered a reservoir and vector of zoonotic pathogens, including Escherichia coli. In view of the increasing emergence of antimicrobial resistant E. coli strains and the on-going discussion about environmental reservoirs, we intended to analyse whether urban rats might be a potential source of putatively zoonotic E. coli combining resistance and virulence. For that, we took fecal samples from 87 brown rats (Rattus norvegicus and tested at least three E. coli colonies from each animal. Thirty two of these E. coli strains were pre-selected from a total of 211 non-duplicate isolates based on their phenotypic resistance to at least three antimicrobial classes, thus fulfilling the definition of multiresistance. As determined by multilocus sequence typing (MLST, these 32 strains belonged to 24 different sequence types (STs, indicating a high phylogenetic diversity. We identified STs, which frequently occur among extraintestinal pathogenic E. coli (ExPEC, such as STs 95, 131, 70, 428, and 127. Also, the detection of a number of typical virulence genes confirmed that the rats tested carried ExPEC-like strains. In particular, the finding of an Extended-spectrum beta-lactamase (ESBL-producing strain which belongs to a highly virulent, so far mainly human- and avian-restricted ExPEC lineage (ST95, which expresses a serogroup linked with invasive strains (O18:NM:K1, and finally, which produces an ESBL-type frequently identified among human strains (CTX-M-9, pointed towards the important role, urban rats might play in the transmission of multiresistant and virulent E. coli strains. Indeed, using a chicken infection model, this strain showed a high in vivo pathogenicity. Imagining the high numbers of urban rats living worldwide, the way to the transmission of putatively zoonotic, multiresistant, and virulent strains might not be far ahead. The unforeseeable consequences of such an emerging public

  12. Comparative genome analysis of Prevotella intermedia strain isolated from infected root canal reveals features related to pathogenicity and adaptation.

    Science.gov (United States)

    Ruan, Yunfeng; Shen, Lu; Zou, Yan; Qi, Zhengnan; Yin, Jun; Jiang, Jie; Guo, Liang; He, Lin; Chen, Zijiang; Tang, Zisheng; Qin, Shengying

    2015-02-25

    Many species of the genus Prevotella are pathogens that cause oral diseases. Prevotella intermedia is known to cause various oral disorders e.g. periodontal disease, periapical periodontitis and noma as well as colonize in the respiratory tract and be associated with cystic fibrosis and chronic bronchitis. It is of clinical significance to identify the main drive of its various adaptation and pathogenicity. In order to explore the intra-species genetic differences among strains of Prevotella intermedia of different niches, we isolated a strain Prevotella intermedia ZT from the infected root canal of a Chinese patient with periapical periodontitis and gained a draft genome sequence. We annotated the genome and compared it with the genomes of other taxa in the genus Prevotella. The raw data set, consisting of approximately 65X-coverage reads, was trimmed and assembled into contigs from which 2165 ORFs were predicted. The comparison of the Prevotella intermedia ZT genome sequence with the published genome sequence of Prevotella intermedia 17 and Prevotella intermedia ATCC25611 revealed that ~14% of the genes were strain-specific. The Preveotella intermedia strains share a set of conserved genes contributing to its adaptation and pathogenic and possess strain-specific genes especially those involved in adhesion and secreting bacteriocin. The Prevotella intermedia ZT shares similar gene content with other taxa of genus Prevotella. The genomes of the genus Prevotella is highly dynamic with relative conserved parts: on average, about half of the genes in one Prevotella genome were not included in another genome of the different Prevotella species. The degree of conservation varied with different pathways: the ability of amino acid biosynthesis varied greatly with species but the pathway of cell wall components biosynthesis were nearly constant. Phylogenetic tree shows that the taxa from different niches are scarcely distributed among clades. Prevotella intermedia ZT

  13. Population Abundance of Potentially Pathogenic Organisms in Intestinal Microbiome of Jungle Crow (Corvus macrorhynchos Shown with 16S rRNA Gene-Based Microbial Community Analysis

    Directory of Open Access Journals (Sweden)

    Isamu Maeda

    2013-01-01

    Full Text Available Jungle Crows (Corvus macrorhynchos prefer human habitats because of their versatility in feeding accompanied with human food consumption. Therefore, it is important from a public health viewpoint to characterize their intestinal microbiota. However, no studies have been involved in molecular characterization of the microbiota based on huge and reliable number of data acquisition. In this study, 16S rRNA gene-based microbial community analysis coupled with the next-generation DNA sequencing techniques was applied to the taxonomic classification of intestinal microbiome for three jungle crows. Clustering of the reads into 130 operational taxonomic units showed that at least 70% of analyzed sequences for each crow were highly homologous to Eimeria sp., which belongs to the protozoan phylum Apicomplexa. The microbiotas of three crows also contained potentially pathogenic bacteria with significant percentages, such as the genera Campylobacter and Brachyspira. Thus, the profiling of a large number of 16S rRNA gene sequences in crow intestinal microbiomes revealed the high-frequency existence or vestige of potentially pathogenic microorganisms.

  14. QMRA (quantitative microbial risk assessment) and HACCP (hazard analysis and critical control points) for management of pathogens in wastewater and sewage sludge treatment and reuse.

    Science.gov (United States)

    Westrell, T; Schönning, C; Stenström, T A; Ashbolt, N J

    2004-01-01

    Hazard Analysis and Critical Control Points (HACCP) was applied for identifying and controlling exposure to pathogenic microorganisms encountered during normal sludge and wastewater handling at a 12,500 m3/d treatment plant utilising tertiary wastewater treatment and mesophilic sludge digestion. The hazardous scenarios considered were human exposure during treatment, handling, soil application and crop consumption, and exposure via water at the wetland-area and recreational swimming. A quantitative microbial risk assessment (QMRA), including rotavirus, adenovirus, haemorrhagic E. coli, Salmonella, Giardia and Cryptosporidium, was performed in order to prioritise pathogen hazards for control purposes. Human exposures were treated as individual risks but also related to the endemic situation in the general population. The highest individual health risk from a single exposure was via aerosols for workers at the belt press for sludge dewatering (virus infection risk = 1). The largest impact on the community would arise if children ingested sludge at the unprotected storage site, although in the worst-case situation the largest number of infections would arise through vegetables fertilised with sludge and eaten raw (not allowed in Sweden). Acceptable risk for various hazardous scenarios, treatment and/or reuse strategies could be tested in the model.

  15. Anti-microbial resistance of non-clinical E. coli isolates from a ...

    African Journals Online (AJOL)

    Because of the wide variations in drug resistance patterns of the E. coli isolates, it is recommended that antibiotic use in the management of colibacillosis of poultry in th