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Sample records for aeromonas

  1. CHLORINE DISINFECTION OF AEROMONAS

    Science.gov (United States)

    The bacterial genus Aeromonas is currently listed on the USEPA's Candidate Contaminant List (CCL). Resistance to chemical disinfection is an essential aspect regarding all microbial groups listed on the CCL. This study was designed to determine the inactivation kinetics of Aeromo...

  2. Identification of hydroxy fatty acids in Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae.

    OpenAIRE

    1985-01-01

    Gas-liquid chromatographic analysis of fatty acid methyl esters obtained from clinical isolates of Aeromonas hydrophila, A. sobria, and A. caviae revealed the presence of two hydroxy fatty acid species, 3-OH 12:0 and 3-OH 14:0.

  3. Virulent Aeromonas hydrophila in channel catfish

    Science.gov (United States)

    In this study, we investigated factors that predisposed catfish to motile aeromonas septicemia (MAS) caused by virulent Aeromonas hydrophila (vAh). Our results revealed that wounding on fish body surface was a prerequisite for vAh infection and disease development. A reproducible waterborne challeng...

  4. Aeromonas hydrophila and Aeromonas veronii predominate among potentially pathogenic ciprofloxacin- and tetracycline-resistant aeromonas isolates from Lake Erie.

    Science.gov (United States)

    Skwor, Troy; Shinko, Jasmine; Augustyniak, Alexander; Gee, Christopher; Andraso, Greg

    2014-02-01

    Members of the genus Aeromonas are ubiquitous in nature and have increasingly been implicated in numerous diseases of humans and other animal taxa. Although some species of aeromonads are human pathogens, their presence, density, and relative abundance are rarely considered in assessing water quality. The objectives of this study were to identify Aeromonas species within Lake Erie, determine their antibiotic resistance patterns, and assess their potential pathogenicity. Aeromonas strains were isolated from Lake Erie water by use of Aeromonas selective agar with and without tetracycline and ciprofloxacin. All isolates were analyzed for hemolytic ability and cytotoxicity against human epithelial cells and were identified to the species level by using 16S rRNA gene restriction fragment length polymorphisms and phylogenetic analysis based on gyrB gene sequences. A molecular virulence profile was identified for each isolate, using multiplex PCR analysis of six virulence genes. We demonstrated that Aeromonas comprised 16% of all culturable bacteria from Lake Erie. Among 119 Aeromonas isolates, six species were identified, though only two species (Aeromonas hydrophila and A. veronii) predominated among tetracycline- and ciprofloxacin-resistant isolates. Additionally, both of these species demonstrated pathogenic phenotypes in vitro. Virulence gene profiles demonstrated a high prevalence of aerolysin and serine protease genes among A. hydrophila and A. veronii isolates, a genetic profile which corresponded with pathogenic phenotypes. Together, our findings demonstrate increased antibiotic resistance among potentially pathogenic strains of aeromonads, illustrating an emerging potential health concern.

  5. Presumptive and Definitive Identification of Aeromonas from infected Ornamental Gold fish (Carassius auratus auratus)

    OpenAIRE

    2013-01-01

    The paper deals with the presumptive identification of Aeromonas, definitive identification of two species of Aeromonas i.e. Aeromonas hydrophila, Aeromonas salmonicida in various organs of Gold fish infected with red disease.

  6. Distribution of Aeromonas Species in the Intestinal Tracts of River Fish

    OpenAIRE

    1995-01-01

    Aeromonas isolates were obtained from fish intestines, water, and sediments from an urban river and identified by the DNA-DNA microplate hybridization method. The isolates were Aeromonas veronii (22%), Aeromonas caviae (18%), Aeromonas hydrophila (13%), Aeromonas sobria (8%), Aeromonas jandaei (7%), and other Aeromonas spp. (33%). Aeromonas species occurred at high densities with high incidences, regardless of season. The results strongly suggest that aeromonads are indigenous in fish intesti...

  7. Aeromonas Hydrophila: A Re-Emerging Pathogen

    Digital Repository Service at National Institute of Oceanography (India)

    Lakshmanaperumalsamy, P.; Thayumanavan, T.; Subashkumar, R.

    ) and for this reason Aeromonas is easily isolated from retail market finfish. Another known reservoir is shellfish, particularly, oysters (Abeyta et al., 1986). Thayumanavan et al., (2003) reported 37 % of the freshly caught seafood (finfish and prawn) collected form... marketed fish and prawn of South India. International Journal of Food Microbiology 76, 165 ? 168. Vivekanandhan, G., Hatha A.A.M., Lakshmanaperumalsamy, P., Prevalence of Aeromonas hydrophila in fish and prawns from the seafood market of Coimbatore, South...

  8. Experimental induction of motile Aeromonas septicemia in channel catfish by waterborne challenge with virulent Aeromonas hydrophila

    Science.gov (United States)

    Motile Aeromonas septicemia (MAS), caused by virulent clonal isolates of Aeromonas hydrophila (vAh), is emerging as a major disease in catfish aquaculture in the Southeastern United States. Predisposing conditions leading to vAh infection in catfish were however largely unknown. The objective of thi...

  9. Infection and disease progress of motile Aeromonas septicemia caused by virulent Aeromonas hydrophila in channel catfish

    Science.gov (United States)

    Motile Aeromonas septicemia (MAS), caused by virulent clonal isolates of Aeromonas hydrophila (vAh), is emerging as a major disease in channel catfish (Ictalurus punctatus) aquaculture in the Southeastern United States. Predisposing conditions leading to vAh infection in catfish were however largely...

  10. Aeromonas flagella and colonisation mechanisms.

    Science.gov (United States)

    Lowry, Rebecca; Balboa, Sabela; Parker, Jennifer L; Shaw, Jonathan G

    2014-01-01

    Aeromonas species are inhabitants of aquatic environments and are able to cause disease in humans and fish among other animals. In aquaculture, they are responsible for the economically important diseases of furunculosis and motile Aeromonas septicaemia (MAS). Whereas gastroenteritis and wound infections are the major human diseases associated with the genus. As they inhabit and survive in diverse environments, aeromonads possess a wide range of colonisation factors. The motile species are able to swim in liquid environments through the action of a single polar flagellum, the flagellin subunits of which are glycosylated; although essential for function the biological role of glycan addition is yet to be determined. Approximately 60% of aeromonads possess a second lateral flagella system that is expressed in viscous environments for swarming over surfaces; both flagellar systems have been shown to be important in the initial colonisation of surfaces. Subsequently, other non-flagellar colonisation factors are employed; these can be both filamentous and non-filamentous. The aeromonads possess a number of fimbrial systems with the bundle-forming MSHA type IV pilus system, having a major role in human cell adherence. Furthermore, a series of outer-membrane proteins have also been implicated in the aeromonad adhesion process. A number of strains are also capable of cell invasion and that maybe linked with the more invasive diseases of bacteraemia or wound infections. These strains employ cell surface factors that allow the colonisation of these niches that protect them from the host's immune system such as S-layers, capsules or particular lipopolysaccharides.

  11. Interlaboratorium vergelijking van het onderzoek naar Aeromonas spp. in drinkwater

    NARCIS (Netherlands)

    Havelaar AH; During M; Versteegh JFM

    1986-01-01

    Door middel van onderzoek van zes kunstmatig besmette gesimuleerde monsters drinkwater ( 4 Aeromonas spp., 1 Klebsiella oxytoca, 1 Pseudomonas aeruginosa) werd een vergelijking gemaakt van de resultaten van Aeromonas onderzoek in 14 laboratoria. De tellingen in de deelnemende laboratoria vertoonde

  12. Biliary tract infections caused by Aeromonas species.

    Science.gov (United States)

    Chao, C M; Lai, C C; Tang, H J; Ko, W C; Hsueh, P-R

    2013-02-01

    This study investigated the clinical and microbiological characteristics of patients with Aeromonas infections of the biliary tract. Patients with bile cultures positive for Aeromonas species during the period July 2004 to December 2011 were identified from a computerized database of a hospital in Taiwan. Patients with Aeromonas infections of the biliary tract were further identified. During the study period, a total of 1,142 isolates of Aeromonas species were obtained from 750 patients. Of those patients, 91 (12.1 %) had Aeromonas infections of the biliary tract. The annual incidence (episodes per 10,000 patient-days) of biliary tract infections caused by all Aeromonas species was 0.31 in 2007, 0.12 in 2010, and 0.27 in 2011. A. hydrophila was the most common species isolated (n = 41, 45.1 %), followed by A. caviae (n = 30, 33.0 %), A. veronii biovar sobria (n = 15, 16.5 %), and A. veronii biovar veronii (n = 5, 5.5 %). The majority of patients (n = 77, 84.6 %) had polymicrobial infections. Hepatobiliary stones (n = 50, 54.9 %) and hepatobiliary cancer (n = 38, 41.8 %) were the most common underlying diseases, followed by diabetes mellitus (n = 29, 31.9 %) and liver cirrhosis (n = 7, 7.7 %). The in-hospital mortality rate was 8.8 %. Infection-related mortality was associated with underlying immunocompromised condition (p = 0.044) and use of mechanical ventilation (p = 0.004), but was not associated with inappropriate antibiotic usage or concomitant bacteremia (n = 8, 8.8 %). In conclusion, biliary tract infections caused by Aeromonas species are not uncommon and can develop in both immunocompromised and immunocompetent patients; however, patients with underlying hepatobiliary diseases are particularly susceptible to these infections.

  13. Characterization of mercury-resistant clinical Aeromonas species.

    Science.gov (United States)

    Pérez-Valdespino, Abigail; Celestino-Mancera, Martin; Villegas-Rodríguez, Viridiana Lorena; Curiel-Quesada, Everardo

    2013-12-01

    Mercury-resistant Aeromonas strains isolated from diarrhea were studied. Resistance occurs via mercuric ion reduction but merA and merR genes were only detected in some strains using PCR and dot hybridization. Results indicate a high variability in mer operons in Aeromonas. To our knowledge, this is the first report of mercury-resistant clinical Aeromonas strains.

  14. Characterization of mercury-resistant clinical Aeromonas species

    Directory of Open Access Journals (Sweden)

    Abigail Pérez-Valdespino

    2013-12-01

    Full Text Available Mercury-resistant Aeromonas strains isolated from diarrhea were studied. Resistance occurs via mercuric ion reduction but merA and merR genes were only detected in some strains using PCR and dot hybridization. Results indicate a high variability in mer operons in Aeromonas. To our knowledge, this is the first report of mercury-resistant clinical Aeromonas strains.

  15. Aeromonas caviae septicemia in immunocompetent gastrointestinal carriers

    Directory of Open Access Journals (Sweden)

    M. Dwivedi

    2008-12-01

    Full Text Available Aeromonas caviae strains have been isolated from blood and stool cultures of three immunocompetent patients, residents of Northern India, who presented with community acquired septicemia without any recent history of diarrhea. Cell culture infectivity test performed on Hep-2 cells have shown substantial degree of invasiveness in the isolated strains. This case unleashes a possibility of asymptomatic gastrointestinal carriage of such strains of A. caviae in a very large population of India, as several areas of India have very high rates of Aeromonas induced acute diarrhea/gastroenteritis (up to 13%. It needs to be appraised further in India as well as other countries having high rates of Aeromonas induced acute diarrhea/gastroenteritis.

  16. Aeromonas phages encode tRNAs for their overused codons.

    Science.gov (United States)

    Prabhakaran, Ramanandan; Chithambaram, Shivapriya; Xia, Xuhua

    2014-01-01

    The GC-rich bacterial species, Aeromonas salmonicida, is parasitised by both GC-rich phages (Aeromonas phages - phiAS7 and vB_AsaM-56) and GC-poor phages (Aeromonas phages - 25, 31, 44RR2.8t, 65, Aes508, phiAS4 and phiAS5). Both the GC-rich Aeromonas phage phiAS7 and Aeromonas phage vB_AsaM-56 have nearly identical codon usage bias as their host. While all the remaining seven GC-poor Aeromonas phages differ dramatically in codon usage from their GC-rich host. Here, we investigated whether tRNA encoded in the genome of Aeromonas phages facilitate the translation of phage proteins. We found that tRNAs encoded in the phage genome correspond to synonymous codons overused in the phage genes but not in the host genes.

  17. Herida antebraquial infectada por Aeromonas hydrophila

    OpenAIRE

    1995-01-01

    Se presenta un caso de celulitis por Aeromonas hydrophila, en un paciente de 23 años, tras una herida antebraquial producida en el medio acuático. La celulitis se resolvió mediante desbridamiento agresivo y quimioterapia. En los controles posteriores no se han apreciado déficits funcionales tras la infección. A case of Aeromonas hidrophila cellulitis developped in a 23-year-old patient, after aquatic environment forearm wound is presented. His cellulitis was effectively resolve...

  18. Quorum Sensing Regulation in Aeromonas hydrophila

    DEFF Research Database (Denmark)

    Garde, Christian; Bjarnsholt, Thomas; Givskov, Michael;

    2010-01-01

    We present detailed results on the C4-HSL-mediated quorum sensing (QS) regulatory system of the opportunistic Gram-negative bacterium Aeromonas hydrophila. This bacterium contains a particularly simple QS system that allows for a detailed modeling of kinetics. In a model system (i...

  19. Multilocus phylogenetic analysis of the genus Aeromonas.

    Science.gov (United States)

    Martinez-Murcia, Antonio J; Monera, Arturo; Saavedra, M Jose; Oncina, Remedios; Lopez-Alvarez, Monserrate; Lara, Erica; Figueras, M Jose

    2011-05-01

    A broad multilocus phylogenetic analysis (MLPA) of the representative diversity of a genus offers the opportunity to incorporate concatenated inter-species phylogenies into bacterial systematics. Recent analyses based on single housekeeping genes have provided coherent phylogenies of Aeromonas. However, to date, a multi-gene phylogenetic analysis has never been tackled. In the present study, the intra- and inter-species phylogenetic relationships of 115 strains representing all Aeromonas species described to date were investigated by MLPA. The study included the independent analysis of seven single gene fragments (gyrB, rpoD, recA, dnaJ, gyrA, dnaX, and atpD), and the tree resulting from the concatenated 4705 bp sequence. The phylogenies obtained were consistent with each other, and clustering agreed with the Aeromonas taxonomy recognized to date. The highest clustering robustness was found for the concatenated tree (i.e. all Aeromonas species split into 100% bootstrap clusters). Both possible chronometric distortions and poor resolution encountered when using single-gene analysis were buffered in the concatenated MLPA tree. However, reliable phylogenetic species delineation required an MLPA including several "bona fide" strains representing all described species.

  20. Aeromonas spp.: ubiquitous or specialized bugs?

    Science.gov (United States)

    Martino, Maria Elena; Fasolato, Luca; Montemurro, Filomena; Novelli, Enrico; Cardazzo, Barbara

    2014-04-01

    The genus Aeromonas comprises ubiquitous bacteria that are known to play several roles in the environment. These bacteria were first described as fish pathogens, but their presence was documented in other reservoirs, such as animals and humans. Today, these bacteria are described as emerging pathogens, but their effective role in human pathogenicity is still controversial. In addition, their taxonomy is heavily debated, as species distinction is often difficult to achieve. To study the interspecies relationships and to investigate their connection with the environment, a multilocus sequence typing scheme previously developed for Aeromonas spp. was applied to 258 strains, and the genetic data were analysed by population software. Sampling was a fundamental step, including several of the main sources of Aeromonas: fish, food products and human cases of disease. The objective was to characterize the isolates and to find potential associations among them according to the following: species, sharing of virulence factors, source and adaptation to a specific habitat. The strains were characterized and demonstrated exceptionally high nucleotide variability in the Aeromonas genus. Among the sampled sources, different species distributions were found, highlighting the occurrence of adaptation processes towards specific habitats.

  1. Aeromonas chitinase degrades chironomid egg masses.

    Science.gov (United States)

    Laviad, Sivan; Golan, Amnon; Shaked, Tamar; Vaizel-Ohayon, Dalit; Halpern, Malka; Pick, Elah

    2016-02-01

    Chironomids are freshwater insects that undergo a complete metamorphosis of four life stages. Chironomid egg masses can be degraded by Vibrio cholerae and some Aeromonas species. Egg mass degradation by V. cholerae requires haemagglutinin protease activity. Our aim was to identify the egg mass degrading (EMD) factor secreted by Aeromonas dhkanesis 3K1C15. Following the hypothesis that the EMD factor of A. dhkanesis is also a protease, secreted proteases were screened, but none of them proved to have the same properties as the EMD factor. Using conventional protein purification methods, we found that the active fraction included chitinases. We further confirmed chitin as a building block of the egg masses. Interestingly, by supplementing bacterial growth media with chitin, we observed unexpected EMD factor activity in Aeromonas isolates that initially were not able to degrade egg masses. Accordingly, we concluded that although strain 3K1C15 secretes chitinases constitutively, most Aeromonas strains secrete chitinases inductively. Induction of chitinases in nature presumably occurs when bacteria are attached to the egg mass habitat, in which chitin is abundant. Considering that chitinases are highly conserved across bacteria phyla, we assume that the role of this enzyme in the bacteria-insect interplay could be wider than is currently thought.

  2. MONITORING FOR AEROMONAS SPECIES AFTER TREATMENT WITH COMMON DRINKING WATER DISINFECTANTS

    Science.gov (United States)

    The sensitivity of Aeromonas spp. To free chlorine, chloramine and ultraviolet (UV) disinfection was determined. Aeromonas hydrophila is a contaminant listed on the USEPA's 1998 Contaminant Candidate List (CCL). Experiments using free chlorine indicated that the Aeromonas spp. ...

  3. Resistance of Salmonds Against Aeromonas Salmonicida

    DEFF Research Database (Denmark)

    Holten-Andersen, Lars; Dalsgaard, Inger; Buchmann, Kurt

    2011-01-01

    Furunculosis, caused by Aeromonas salmonicida, continues to be a health problem for the growing salmonid aquaculture. Despite effective vaccination programs regular outbreaks occur at Danish trout farms calling for repeated antibiotic treatment. We hypothesized that a difference in natural...... susceptibility to this disease might exist between Baltic salmon and the widely used rainbow trout. Hence, a cohabitation challenge model was applied to investigate the relative susceptibility to infection with Aeromonas salmonicida in rainbow trout and Baltic salmon. The course of infection was monitored daily...... over a 30-day period post challenge and the results were summarized in mortality curves. A. salmonicida was recovered from mortalities during the entire test period. At day 30 the survival was 6.2 % and 34.0 % for rainbow trout and Baltic salmon, respectively. Significant differences in susceptibility...

  4. Aeromonas dhakensis, an increasingly recognized human pathogen

    Directory of Open Access Journals (Sweden)

    Po Lin eChen

    2016-05-01

    Full Text Available Aeromonas dhakensis was first isolated from children with diarrhea in Dhaka, Bangladesh and described in 2002. In the past decade, increasing evidence indicate this species is widely distributed in the environment and can cause a variety of infections both in human and animals, especially in coastal areas. A. dhakensis is often misidentified as A. hydrophila, A. veronii or A. caviae by commercial phenotypic tests in the clinical laboratory. Correct identification relies on molecular methods. Increasingly used matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS may be able to identify Aeromonas specie rapidly and accurately. A. dhakensis has shown its potent virulence in different animal models and clinical infections. Although several virulence factors had been reported, no single mechanism is conclusive. Characteristically A. dhakensis is the principal species causing soft tissue infection and bacteremia, especially among patients with liver cirrhosis or malignancy. Of note, A. dhakensis bacteremia is more lethal than bacteremia due to other Aeromonas species. The role of this species in gastroenteritis remains controversial. Third generation cephalosporins and carbapenems should be used cautiously in the treatment of severe A. dhakensis infection due to the presence of AmpC β-lactamase and metallo-β-lactamase genes, and optimal regimens may be cefepime or fluoroquinolones. Studies of bacterial virulence factors and associated host responses may provide the chance to understand the heterogeneous virulence between species. The hypothesis A. dhakensis with varied geographic prevalence and enhanced virulence that compared to other Aeromonas species warrants more investigations.

  5. Aeromonas in Arab countries: 1995-2014.

    Science.gov (United States)

    Ghenghesh, Khalifa Sifaw; Rahouma, Amal; Zorgani, Abdulaziz; Tawil, Khaled; Al Tomi, Abdurazzaq; Franka, Ezzadin

    2015-10-01

    The aim of this review is to provide information on the prevalence, clinical syndromes, and antimicrobial resistance and therapy of Aeromonas spp. infections in Arab countries. The data were obtained by an English language literature search from 1995 to 2014 of Medline and PubMed for papers using the search terms "Aeromonas+name of Arab country (i.e. Algeria, Egypt, etc.)". Additional data were obtained from a Google search using the aforementioned terms. The organisms have been reported from diarrheal children, patients with cholera-like diarrhea, an outbreak of acute gastroenteritis and from different types of animals, foods and water source in several Arab countries in the Middle East and North Africa with predominance of A. hydrophila, A. caviae and A. sobria. Using molecular techniques few studies reported genes encoding several toxins from aeromonads isolated from different sources. Among the antimicrobials examined in the present review third generation cephalosporins, fluoroquinolones and aminoglycosides showed excellent activity and can be employed in the treatment of Aeromonas-associated human infections in Arabic countries. Whenever possible, treatment should be guided by the susceptibility testing results of the isolated organism. In the future, studies employing molecular testing methods are required to provide data on circulating genospecies and their modes of transmission in the community, and on their mechanisms of resistance to antimicrobials. Microbiology laboratories and research centers are encouraged to look for these organisms in clinical, food and water sources to attain a better understanding of the public health risks from these organisms in Arab countries.

  6. Aeromonas aquatica sp. nov., Aeromonas finlandiensis sp. nov. and Aeromonas lacus sp. nov. isolated from Finnish waters associated with cyanobacterial blooms.

    Science.gov (United States)

    Beaz-Hidalgo, R; Latif-Eugenín, F; Hossain, M J; Berg, K; Niemi, R M; Rapala, J; Lyra, C; Liles, M R; Figueras, M J

    2015-05-01

    Three groups of Aeromonas strains isolated from Finland lakes experiencing cyanobacterial blooms could not be assigned to any known species of this genus on the basis of 16S rRNA and rpoD gene sequences. The Multilocus Phylogenetic Analysis (MLPA) of the concatenated sequence of seven genes (gyrB, rpoD, recA, dnaJ, gyrA, dnaX and atpD; 4093bp) showed that the three groups of strains did not cluster with any known Aeromonas spp. and formed three independent lineages. This was confirmed by performing the analysis with their closest relatives using 15 genes (the latter 7 and cpn60, dnaK, gltA, mdh, radA, rpoB, tsf, zipA; 8751bp). Furthermore, ANI results between the genomes of the type strains of the three potential new species and those of their close relatives were all Aeromonas species on the basis of several phenotypic characters. This polyphasic study revealed that the 3 groups of strains represent 3 novel Aeromonas species for which the names Aeromonas aquatica sp. nov. (type strain AE235T=CECT 8025T=LMG 26712T), Aeromonas finlandiensis sp. nov. (type strain 4287DT=CECT 8028T=LMG 26709T) and Aeromonas lacus sp. nov. (type strain AE122T=CECT 8024T=LMG 26710T) are proposed.

  7. Isolation and antibiotic sensitivity of Aeromonas from children with diarrhea

    Directory of Open Access Journals (Sweden)

    Meiyanti Meiyanti

    2016-02-01

    Full Text Available Aeromonas species are gram-negative, motile, facultative anaerobic, rod shaped, oxidase positive bacteria of the recently assigned family Aeromonadaceae. The significance of Aeromonas species as causative agent of human diarrhoea has recently been established. The aim of the present study was to investigate the distribution, and antibiotic sensitivity of Aeromonas in nonhospitalized children with diarrhea.One hundred and seventeen rectal swabs from children with diarhhea were cultured for isolation of Aeromonas organisms as the etiological agents. In addition to Aeromonas, other enteric pathogens were also isolated. Overall, the isolates of enteric pathogens amounted to 36.8%, consisting of Salmonella, Shigella, Aeromonas, and Vibrio. Aeromonas was only found in 5.1% of cultures, with a ratio of A. caviae and A. hydrophila of 2:1, while Salmonella made up the majority of causative organisms with an isolation frequency of 18.8%, followed by Shigella with 11.1%. In this study no isolates of Vibrio cholerae O1 were found as etiological agents of diarrhea; however, V. cholerae non-O1 and V. parahaemolyticus were found in small numbers (<1%. All isolates of Aeromonas were resistant to ampicillin and tetracycline, but sensitive to ciprofloxacin and ceftriaxone, as were the other enteric pathogens. Although the frequency of isolation of these enteric pathogens was higher than for Vibrio spp., their role in infective diarrhea was less clearcut in comparison with Salmonella and Shigella.

  8. Complete genome sequence of Aeromonas hydrophila AL06-06

    Science.gov (United States)

    Aeromonas hydrophila occurs in freshwater environments and infects fish and mammals. In this work, we report the complete genome sequence of Aeromonas hydrophila AL06-06, which was isolated from diseased goldfish and is being used for comparative genomic studies with A. hydrophila strains causing ba...

  9. Draft genome sequence of Aeromonas hydrophila TN97-08

    Science.gov (United States)

    Aeromonas hydrophila is an opportunistic Gram-negative species causing disease in fish and mammals. The genus Aeromonas affects a variety of aquatic organisms and lives in diverse aquatic ecosystems (1). There are 39 A. hydrophila genomes currently available in GenBank. In the current study, we repo...

  10. OVERVIEW: DISINFECTION OF HELICOBACTER PYLORI AND AEROMONAS SPECIES

    Science.gov (United States)

    Helicobacter pylori and Aeromonas hydrophila are contaminants listed on the USEPA's 1998 Contaminant Candidate List (CCL).The sensitivity of H. pylori to chlorine and of Aeromonas spp. to inactivation by free chlorine, chloramine and ultraviolet (UV) was examined. Selective and...

  11. CHARACTERIZATION OF AEROMONAS VIRULENCE USING AN IMMUNOCOMPROMISED MOUSE MODEL

    Science.gov (United States)

    An immunocompromised mouse model was used to characterize Aeromonas strains for their ability to cause opportunistic, extraintestinal infections. A total of 34 isolates of Aeromonas (A. hydrophila [n = 12]), A. veronii biotype sobria [n = 7], A. caviae [n = 4], A. enchelia [n = 4...

  12. Chitin degradation and metabolism by virulent Aeromonas hydropila

    Science.gov (United States)

    Aeromonas hydrophila is the causal agent of motile Aeromonas septicemia (MAS) in catfish and other warm-water fishes. Severe outbreak of MAS caused by virulent A. hydrophila (vAh) was reported in 2009 in the Southeastern United States; the disease has since resulted in loss of millions of pounds of ...

  13. Comparative in vitro activities of selected antimicrobial agents against Aeromonas species and Plesiomonas shigelloides.

    OpenAIRE

    1985-01-01

    The in vitro antimicrobial susceptibilities of fecal isolates of Aeromonas caviae, Aeromonas hydrophila, Aeromonas sobria, and Plesiomonas shigelloides were tested by agar dilution. This in vitro study suggested that ciprofloxacin, enoxacin, norfloxacin, tetracycline, and trimethoprim-sulfamethoxazole might be effective oral agents for treatment of diarrhea involving Aeromonas spp. or P. shigelloides.

  14. Isolation of Aeromonas spp. from Food Products: Emerging Aeromonas Infections and Their Significance in Public Health.

    Science.gov (United States)

    Alhazmi, Mohammad Ismail

    2015-01-01

    Aeromonas spp. are opportunistic pathogens causing a broad spectrum of human illnesses like gastroenteritis, chronic diarrhea, wound infections, peritonitis, urinary tract infections, and septicemia. Their ability to grow in foods stored in a refrigerator poses a substantial threat for human consumption. We investigated the prevalence of Aeromonas from commercial food products across Riyadh, Saudi Arabia. A total of 250 samples were randomly collected and processed for the isolation and identification of Aeromonas by morphological and biochemical means and for their identification by PCR. A total of 102 strains of Aeromonas were isolated, including 47% from raw meat samples, 34% from raw fish samples, and 18.6% from milk and dairy products; 56.8% were identified as A. hydrophila and 43.1% as A. sobria. Antibiotic susceptibility tests done revealed 100% sensitivity to chloramphenicol, colistin, ciprofloxacin, and nitrofurantoin. 16S rDNA PCR revealed the presence of the 953 bp fragment in all the strains. The present investigation suggested the occurrences of A. sobria and A. hydrophila in human consumable stored and refrigerated foods.

  15. Chironomid egg masses harbour the clinical species Aeromonas taiwanensis and Aeromonas sanarellii.

    Science.gov (United States)

    Beaz-Hidalgo, Roxana; Shakèd, Tamar; Laviad, Sivan; Halpern, Malka; Figueras, María J

    2012-12-01

    Bacteria of the genus Aeromonas are found worldwide in aquatic environments and may produce human infections. In 2010, two new clinical species, Aeromonas sanarellii and Aeromonas taiwanensis, were described on the basis of one strain recovered from wounds of hospitalized patients in Taiwan. So far, only four environmental isolates of A. sanarellii and one of A. taiwanensis have been recorded from waste water in Portugal and an additional clinical strain of A. taiwanensis from the faeces of a patient with diarrhoea in Israel. In the present study, strains belonging to these two species were identified from chironomid egg masses from the same area in Israel by sequencing the rpoD gene. This represents a new environmental habitat for these novel species. The first data on the virulence genes and antibiotic susceptibility are provided. The isolates of these two new species possess multiple virulence genes and are sensitive to amikacin, aztreonam, cefepime, cefoxatime, ceftazidime, ciprofloxacin, gentamicin, piperacillin-tazobactam, tigecycline, tobramycin, trimethoprim-sulfamethoxazole and imipenem. The key phenotypic tests for the differentiation of these new species from their closest relative Aeromonas caviae included the utilization of citrate, growth at 45 °C in sheep blood agar and acid production of cellobiose.

  16. Reassessment of the Enteropathogenicity of Mesophilic Aeromonas Species

    Science.gov (United States)

    Teunis, Peter; Figueras, Maria J.

    2016-01-01

    Cases of Aeromonas diarrhea have been described all over the world. The genus Aeromonas includes ca. 30 species, of which 10 have been isolated in association with gastroenteritis. The dominating species that account for ca. 96% of the identified strains are Aeromonas caviae, A. veronii, A. dhakensis, and A. hydrophila. However, the role of Aeromonas as a true enteropathogen has been questioned on the basis of the lack of outbreaks, the non-fulfillment of Koch’s postulates and the low numbers of acute illnesses in the only existing human challenge study. In the present study we reassess the enteropathogenicity of Aeromonas using dose response models for microbial infection and acute illness. The analysis uses the data from the human challenge study and additional data from selected outbreak investigations where the numbers exposed and the dose were reported, allowing their inclusion as “natural experiments”. In the challenge study several cases of asymptomatic shedding were found (26.3%, 15/57), however, only 3.5% (2/57) of those challenged with Aeromonas developed acute enteric symptoms (i.e., diarrhea). The “natural experiments” showed a much higher risk of illness associated with exposure to Aeromonas, even at moderate to low doses. The median dose required for 1% illness risk, was ~1.4 × 104 times higher in the challenge study (1.24 × 104 cfu) compared to natural exposure events (0.9 cfu). The dose response assessment presented in this study shows that the combined challenge and outbreak data are consistent with high infectivity of Aeromonas, and a wide range of susceptibility to acute enteric illness. To illustrate the outcomes, we simulate the risk associated with concentrations of Aeromonas found in different water and food matrices, indicating the disease burden potentially associated with these bacteria. In conclusion this study showed that Aeromonas is highly infectious, and that human susceptibility to illness may be high, similar to

  17. Insight into the mobilome of Aeromonas strains

    Directory of Open Access Journals (Sweden)

    Marta ePiotrowska

    2015-05-01

    Full Text Available The mobilome is a pool of genes located within mobile genetic elements (MGE, such as plasmids, IS elements, transposons, genomic/pathogenicity islands, and integron-associated gene cassettes. These genes are often referred to as flexible and may encode virulence factors, toxic compounds as well as resistance to antibiotics. The phenomenon of MGE transfer between bacteria, known as horizontal gene transfer (HGT, is well documented. The genes present on MGE are subject to continuous processes of evolution and environmental changes, largely induced or significantly accelerated by man. For bacteria, the only chance of survival in an environment contaminated with toxic chemicals, heavy metals and antibiotics is the acquisition of genes providing the ability to survive in such conditions. The process of acquiring and spreading antibiotic resistance genes (ARG is of particular significance, as it is important for the health of humans and animals. Therefore, it is important to thoroughly study the mobilome of Aeromonas spp. that is widely distributed in various environments, causing many diseases in fishes and humans. This review discusses the recently published information on MGE prevalent in Aeromonas spp. with special emphasis on plasmids belonging to different incompatibility groups, i.e., IncA/C, IncU, IncQ, IncF, IncI and ColE-type. The vast majority of plasmids carry a number of different transposons (Tn3, Tn21, Tn1213, Tn1721, Tn4401, the 1st, 2nd or 3rd class of integrons, IS elements (e.g. IS26, ISPa12, ISPa13, ISKpn8, ISKpn6 and encode determinants such as antibiotic and mercury resistance genes, as well as virulence factors. Although the actual role of Aeromonas spp. as a human pathogen remains controversial, species of this genus may pose a serious risk to human health. This is due to the considerable potential of their mobilome, particularly in terms of antibiotic resistance and the possibility of the horizontal transfer of resistance

  18. AEROMONAS SALMONICIDA INFECTION IN VACCINATED RAINBOW TROUT

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Skov, Jakob; Mohammad, Rezkar Jaafar

    In vivo testing of any candidate vaccine is influenced by the choice of challenge method and the external environmental conditions. In the present study, a comparative challenge study was performed to evaluate the efficacy of different vaccines against the bacterial pathogen Aeromonas salmonicida...... in saltwater condition produced less mortality compared to freshwater, probably due to the growth inhibition of A. salmonicida in saline condition which was also verified by in vitro assay. One of the experimental vaccines emulsified in water in oil adjuvant showed a protection comparable...... effects due to oil adjuvants, and the importance of choice of challenge methods used will be discussed....

  19. Effectiveness of radiation processing in elimination of Aeromonas from food

    Energy Technology Data Exchange (ETDEWEB)

    Nagar, Vandan [Food Technology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Bandekar, Jayant R., E-mail: jrb@barc.gov.i [Food Technology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2011-08-15

    Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Contaminated water, sprouts, vegetables, seafood and food of animal origin have been considered to be the important sources of Aeromonas infection. In the present study, radiation sensitivity of indigenous strains of Aeromonas spp. from different food samples was evaluated. The decimal reduction dose (D{sub 10}) values of different Aeromonas isolates in saline at 0-4 {sup o}C were in the range of 0.031-0.046 kGy. The mixed sprouts, chicken and fish samples were inoculated with a cocktail of five most resistant isolates (A. salmonicida Y567, A. caviae A85, A. jandaei A514A, A. hydrophila CECT 839{sup T} and A. veronii Y47) and exposed to {gamma} radiation to study the effectiveness of radiation treatment in elimination of Aeromonas. D{sub 10} values of Aeromonas cocktail in mixed sprouts, chicken and fish samples were found to be 0.081{+-}0.001, 0.089{+-}0.003 and 0.091{+-}0.003 kGy, respectively. Radiation treatment with a 1.5 kGy dose resulted in complete elimination of 10{sup 5} CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples. No recovery of Aeromonas was observed in the 1.5 kGy treated samples stored at 4 {sup o}C up to 12 (mixed sprouts) and 7 days (chicken and fish samples), even after enrichment and selective plating. This study demonstrates that a 1.5 kGy dose of irradiation treatment could result in complete elimination of 10{sup 5} CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples.

  20. Effectiveness of radiation processing in elimination of Aeromonas from food

    Science.gov (United States)

    Nagar, Vandan; Bandekar, Jayant R.

    2011-08-01

    Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Contaminated water, sprouts, vegetables, seafood and food of animal origin have been considered to be the important sources of Aeromonas infection. In the present study, radiation sensitivity of indigenous strains of Aeromonas spp. from different food samples was evaluated. The decimal reduction dose (D10) values of different Aeromonas isolates in saline at 0-4 °C were in the range of 0.031-0.046 kGy. The mixed sprouts, chicken and fish samples were inoculated with a cocktail of five most resistant isolates (A. salmonicida Y567, A. caviae A85, A. jandaei A514A, A. hydrophila CECT 839T and A. veronii Y47) and exposed to γ radiation to study the effectiveness of radiation treatment in elimination of Aeromonas. D10 values of Aeromonas cocktail in mixed sprouts, chicken and fish samples were found to be 0.081±0.001, 0.089±0.003 and 0.091±0.003 kGy, respectively. Radiation treatment with a 1.5 kGy dose resulted in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples. No recovery of Aeromonas was observed in the 1.5 kGy treated samples stored at 4 °C up to 12 (mixed sprouts) and 7 days (chicken and fish samples), even after enrichment and selective plating. This study demonstrates that a 1.5 kGy dose of irradiation treatment could result in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples.

  1. Histopathological findings in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with 3 different Aeromonas species.

    Science.gov (United States)

    Zepeda-Velázquez, Andrea Paloma; Vega-Sánchez, Vicente; Salgado-Miranda, Celene; Soriano-Vargas, Edgardo

    2015-07-01

    This study describes the macroscopic and microscopic lesions in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with genetically identified Aeromonas salmonicida, A. hydrophila, and A. veronii species. The genus Aeromonas includes bacteria that naturally inhabit both waterways and organisms. At least 27 Aeromonas species have been identified to date, some of which can cause significant economic losses in aquaculture. As up to 68.8% of Aeromonas isolates may be misidentified in routine biochemical and phenotypic tests, however, reported cases of Aeromonas infection in fish may be wrongly identified. Our findings confirmed that the 3 Aeromonas species studied are associated with septicemia and dermal lesions in rainbow trout.

  2. Emerging Aeromonas Species Infections and Their Significance in Public Health

    OpenAIRE

    Igbinosa, Isoken H.; Ehimario U. Igumbor; Farhad Aghdasi; Mvuyo Tom; Anthony I. Okoh

    2012-01-01

    Aeromonas species are ubiquitous bacteria in terrestrial and aquatic milieus. They are becoming renowned as enteric pathogens of serious public health concern as they acquire a number of virulence determinants that are linked with human diseases, such as gastroenteritis, soft-tissue, muscle infections, septicemia, and skin diseases. Proper sanitary procedures are essential in the prevention of the spread of Aeromonas infections. Oral fluid electrolyte substitution is employed in the preventio...

  3. Pneumonia caused by Aeromonas species in Taiwan, 2004-2011.

    Science.gov (United States)

    Chao, C M; Lai, C C; Tsai, H Y; Wu, C J; Tang, H J; Ko, W C; Hsueh, P-R

    2013-08-01

    We investigated the clinical characteristics of patients with pneumonia caused by Aeromonas species. Patients with pneumonia caused by Aeromonas species during the period 2004 to 2011 were identified from a computerized database of a regional hospital in southern Taiwan. The medical records of these patients were retrospectively reviewed. Of the 84 patients with pneumonia due to Aeromonas species, possible Aeromonas pneumonia was diagnosed in 58 patients, probable Aeromonas pneumonia was diagnosed in 18 patients, and pneumonia due to Aeromonas was conclusively diagnosed in 8 patients. Most of the cases of Aeromonas pneumonia developed in men and in patients of advanced age. A. hydrophila (n = 50, 59.5 %) was the most common pathogen, followed by A. caviae (n = 24, 28.6 %), A. veronii biovar sobria (n = 7, 8.3 %), and A. veronii biovar veronii (n = 3, 3.6 %). Cancer (n = 37, 44.0 %) was the most common underlying disease, followed by diabetes mellitus (n = 27, 32.1 %). Drowning-associated pneumonia developed in 6 (7.1 %) patients. Of 47 patients who were admitted to the intensive care ward, 42 patients developed acute respiratory failure and 24 of those patients died. The overall in-hospital mortality rate was significantly associated with liver cirrhosis, cancer, initial presentation of shock, and usage of mechanical ventilation. In conclusion, Aeromonas species should be considered as one of the causative pathogens of severe pneumonia, especially in immunocompromised patients, and should be recognized as a cause of drowning-associated pneumonia. Cirrhosis, cancer, and shock as the initial presenting symptom are associated with poor outcome.

  4. Post-traumatic osteomyelitis due to aeromonas species

    Directory of Open Access Journals (Sweden)

    Gunasekaran L

    2009-01-01

    Full Text Available We report a case of Aeromonas osteomyelitis due to injury in a sewage worker. He presented with cellulitis of the left foot. Radiographs showed evidence of osteomyelitis involving the head and neck of the fifth metatarsal. Aeromonas species was isolated from the tissue and swab from the foot. The head and neck of the fifth metatarsal were excised and the patient improved on 4 weeks of intravenous meropenem followed by 4 weeks of oral clindamycin and ciprofloxacin.

  5. Skin and soft-tissue infections caused by Aeromonas species.

    Science.gov (United States)

    Chao, C M; Lai, C C; Tang, H J; Ko, W C; Hsueh, P-R

    2013-04-01

    This study investigated the clinical characteristics of patients with skin and soft-tissue infections (SSTIs) due to Aeromonas species. Patients with SSTIs caused by Aeromonas species during the period from January 2009 to December 2011 were identified from a computerized database of a regional hospital in southern Taiwan. The medical records of these patients were retrospectively reviewed. A total of 129 patients with SSTIs due to Aeromonas species were identified. A. hydrophila (n = 77, 59.7 %) was the most common pathogen, followed by A. veronii biovar sobria (n = 22, 17.1 %), A. veronii biovar veronii (n = 20, 15.5 %), A. caviae (n = 9, 7.0 %), and A. schubertii (n = 1, 0.8 %). The most common isolates obtained from patients with polymicrobial infections were Klebsiella species (n = 33), followed by Enterococcus spp. (n = 24), Enterobacter spp. (n = 21), Escherichia coli (n = 17), Staphylococcus spp. (n = 17), Streptococcus spp. (n = 17), and Acinetobacter spp. (n = 15). Liver cirrhosis and concomitant bacteremia were more common among patients with monomicrobial Aeromonas SSTIs than among patients with polymicrobial SSTIs. Nine (7 %) patients required limb amputations. The in-hospital mortality rate was 1.6 %. In conclusion, Aeromonas species should be considered as important causative pathogens of SSTIs, and most infections are polymicrobial. In addition, the clinical presentation differs markedly between patients with monomicrobial and those with polymicrobial Aeromonas SSTIs.

  6. Aeromonas hydrophila Sepsis Mimicking Vibrio vulnificus Infection.

    Science.gov (United States)

    Park, Se Young; Nam, Hyun Min; Park, Kun; Park, Seok Don

    2011-09-01

    Aeromonas hydrophila is a facultatively anaerobic, asporogenous gram-negative rod that has often been regarded as an opportunistic pathogen in hosts with impairment of a local or general defense mechanism. A 68-year-old alcoholic woman presented with shock and gangrene on the right arm. At first, her clinical presentations were severe painful erythematous swelling that worsened within a few hours with development of gangrene, edema, and blisters. Bullous fluid and blood cultures yielded A. hydrophila. Histopathological findings of sections obtained from the vesicle revealed subepidermal vesicles; necrosis of the epidermis, papillary dermis, and subcutaneous fat; and massive hemorrhage in the subcutis. Despite all efforts to save the patient, she died 8 hours after admission. Clinical features of A. hydrophila sepsis resemble those of Vibrio vulnificus sepsis. Therefore, in addition to the case report, we compared the cultural, biochemical, and morphological differences between A. hydrophila and V. vulnificus for facilitation of early and accurate identification of the causative agent.

  7. Peritonitis bacteriana espontánea y bacteriemia por Aeromonas hydrophila Spontaneous bacterial peritonitis and bacteraemia due to Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    J. J. García-Irure

    2003-12-01

    Full Text Available La peritonitis bacteriana es una complicación frecuente en los pacientes cirróticos. De los gérmenes etiológicos, Aeromonas es muy poco frecuente. Presentamos un caso clínico de un paciente cirrótico con peritonitis y bacteriemia por Aeromonas hydrophila. Este microorganismo es un bacilo gramnegativo de la familia Vibrionaceae. En el ser humano produce gastroenteritis con mucha frecuencia. De forma excepcional puede dar origen a infecciones extraintestinales, sobre todo en pacientes inmunodeprimidos. La peritonitis por Aeromonas se ha descrito en asociación a peritonitis bacteriana espontánea en pacientes cirróticos, en pacientes en diálisis peritoneal y en casos de peritonitis secundaria a perforación intestinal.Bacterial peritonitis is a frequent complication in cirrhotic patients. Amongst the aetiological germs, Aeromonas is very infrequent. We present the clinical case of a cirrhotic patient with peritonitis and bacteraemia due to Aeromonas hydrophila. This micro-organism is a Gram-negative bacillus of the Vibrionaceae family. It very frequently produces gastroenteritis in the human being. Exceptionally it can give rise to extraintestinal infections, especially in immunodepressed patients. Peritonitis due to Aeromonas has been described in association with spontaneous bacterial peritonitis in cirrhotic patients, in patients on peritoneal dialysis and in cases of peritonitis secondary to intestinal perforation.

  8. Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract

    Science.gov (United States)

    Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus,. Microarray profiling of...

  9. Interlaboratorium vergelijking van het onderzoek naar Aeromonas spp. in drinkwater (tweede onderzoek)

    NARCIS (Netherlands)

    Versteegh JFM; During M; Heisterkamp SH; Havelaar AH

    1988-01-01

    Door middel van kwantitatief onderzoek naar Aeromonas-bacterien in drie verschillende monsters water (De Bilt, De Meent en De Laak) werd een vergelijking gemaakt van de resultaten van Aeromonas onderzoek in 15 laboratoria in het kader van het deelproject: "Aeromonas in drinkwater". Varian

  10. MONITORING THE EFFECTIVENESS OF UV DISINFECTION OF AEROMONAS SPP. USING SELECTIVE AND NON-SELECTIVE MEDIA

    Science.gov (United States)

    This research was initiated to determine the sensitivity of Aeromonas spp. to ultraviolet (UV) disinfection. Aeromonas hydrophila is a contaminant listed on the USEPA's 1998 CCL. Three different Aeromonas spp. (A. hydrophila, A. sobria and A. caviae) were tested using membrane fi...

  11. Aeromonas australiensis sp. nov., isolated from irrigation water.

    Science.gov (United States)

    Aravena-Román, Max; Beaz-Hidalgo, Roxana; Inglis, Timothy J J; Riley, Thomas V; Martínez-Murcia, Antonio J; Chang, Barbara J; Figueras, Maria Jose

    2013-06-01

    A Gram-negative, facultatively anaerobic bacillus, designated strain 266(T), was isolated from an irrigation water system in the south-west of Western Australia. Analysis of the 16S rRNA gene sequence confirmed that strain 266(T) belonged to the genus Aeromonas, with the nearest species being Aeromonas fluvialis (99.6% similarity to the type strain, with 6 nucleotide differences) followed by Aeromonas veronii and Aeromonas allosaccharophila (both 99.5%). Analysis of gyrB and rpoD sequences suggested that strain 266(T) formed a phylogenetic line independent of other species in the genus. This was confirmed using the concatenated sequences of six housekeeping genes (gyrB, rpoD, recA, dnaJ, gyrA and dnaX) that also indicated that A. veronii and A. allosaccharophila were the nearest relatives. DNA-DNA reassociation experiments and phenotypic analysis further supported the conclusion that strain 266(T) represents a novel species, for which the name Aeromonas australiensis sp. nov. is proposed, with type strain 266(T) (=CECT 8023(T) =LMG 26707(T)). [corrected].

  12. Enhancement of protective immunity in European eel(Anguilla anguilla)against Aeromonas hydrophila and Aeromonas sobria by a recombinant Aeromonas outer membrane protein

    Institute of Scientific and Technical Information of China (English)

    Ruizhang Guan; Jing Xiong; Wenshu Huang; Songlin Guo

    2011-01-01

    To develop a vaccine,which can simultaneously prevent the diseases caused by various pathogenic bacteria in fish,we try to find a conserved outer membrane protein(OMP)antigen from different bacterial pathogens.In this study,an OMP fragment of 747 by(named as Omp-G),whichwas highly conserved in seven Aeromonas OMP sequences from the NCBI database,was amplified by PCR from one Aeromonas sobria strain(1110)and two Aeromonas hydrophila strains(1327 and B33)with the designed specific primers.The sequence was cloned into pGEX-2T(6 × His-tag)vector,expressed in Escherichia coli system,and then the recombinant protein(named as rOmp-G)was purified with nickel chelating affinity chromatography.The purified romp-G showed a good immunogenicity in rabbits and well-conserved characteristics in these three pathogens by enzyme-linked immunosorbed assay.Furthermore,the rOmp-G also showed good immunogenicity in eels(Anguilla anguilla)for eliciting significantly increased specific antibodies(P<0.01),and providing higher protection efficiencies(P<0.05)after the pathogens challenge.The values of the relative percent survival in eels were 70% and 50% for two A.hydrophila strain challenge,and 75% for A.sobria strain challenge.This is the first report of a potential vaccination in eels that simultaneously provide protectiveness against different Aeromonas pathogens with a conserved partial OMP.

  13. The impact of quorum sensing on the virulence of Aeromonas hydrophila and Aeromonas salmonicida towards burbot (Lota lota L.) larvae.

    Science.gov (United States)

    Natrah, F M I; Alam, Md Iftakharul; Pawar, Sushant; Harzevili, A Shiri; Nevejan, Nancy; Boon, Nico; Sorgeloos, Patrick; Bossier, Peter; Defoirdt, Tom

    2012-09-14

    In this study, the link between quorum sensing in Aeromonas spp. and its virulence towards burbot (Lota lota) was investigated. High mortality occurred in burbot juveniles challenged with Aeromonas salmonicida HN-00, but not in juveniles challenged with Aeromonas hydrophila AH-1N. Meanwhile, both A. hydrophila AH-1N and A. salmonicida HN-00 were virulent towards larvae. The effect of quorum sensing on the virulence of A. hydrophila AH-1N towards burbot larvae was further investigated using quorum sensing mutants (N-(butyryl)-L-homoserine lactone production and receptor mutants). Challenge with these mutants resulted in higher survival of burbot larvae when compared to challenge with the wild type, and the addition of the signal molecule N-butyryl-L-homoserine lactone restored the virulence of the quorum sensing production mutant. Moreover, quorum sensing inhibitors protected the burbot larvae from both Aeromonas strains. Finally, the freshwater micro-algae Chlorella saccharophila and Chlamydomonas reinhardtii, which are able to interfere with quorum sensing, also protected burbot from the pathogens. However, QS interference was unlikely to be the only mechanism. This study revealed that the virulence of Aeromonas spp. towards burbot is regulated by quorum sensing and that quorum sensing inhibitors and micro-algae are promising biocontrol agents.

  14. Traveller's diarrohea caused by Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    M. Martín Delgado

    2001-06-01

    Full Text Available Aeromonas hydrophila is a bacteria frequently found in fresh water and saline water. Certain strains of the species have been known to cause disease in fish and amphibians for several years, although some controversy exists about its ability to cause illness in humans. Nevertheless, either through open wounds or contaminated food or water, it can give rise to infection. However, almost all articles refer to isolated cases, rather than to outbreaks.In most cases it produces gastroenteritis in healthy people, whilst possibly causing septicemia in people with low inmmunity.In 1998, there was concern in the hotel sector due to a considerable rise in the number of cases of gastroenteritis among tourists holidaying in certain areas of the coast of the island of Tenerife.The Public Health Services of the Canarian Community iniciated an epidemiological study in order to establish the magnitude of the problem and the associated factors.The inicial analysis showed a large number of tourists affected but not seriously, and only in one particular area of the coast. This suggested traveller’s diarrohea probably associated with contaminated drinking water.

  15. Reclassification of Aeromonas hydrophila subsp. dhakensis Huys et al. 2002 and Aeromonas aquariorum Martínez-Murcia et al. 2008 as Aeromonas dhakensis sp. nov. comb nov. and emendation of the species Aeromonas hydrophila.

    Science.gov (United States)

    Beaz-Hidalgo, Roxana; Martínez-Murcia, Antonio; Figueras, Maria José

    2013-05-01

    Previous studies indicate that Aeromonas aquariorum and Aeromonas hydrophila subsp. dhakensis are the same taxon and suggest that they should be synonymized. Using a polyphasic approach, the phenotypic and phylogenetic relationship of A. aquariorum with the 3 defined A. hydrophila subspecies (i.e. dhakensis, hydrophila, ranae) was investigated. Phylogenetic trees derived from the 16S rRNA, rpoD or gyrB genes and a multilocus phylogenetic analysis (with the concatenated sequences of gyrB, rpoD, recA, dnaJ and gyrA) confirmed that both A. aquariorum and A. hydrophila subsp. dhakensis are a unique taxon, different from the other A. hydrophila subspecies, corroborating the phenotypic and DNA-DNA hybridization (DDH) results. A formal synonymization of A. aquariorum and A. hydrophila subsp. dhakensis and a reclassification of both as Aeromonas dhakensis sp. nov. comb nov. is therefore proposed.

  16. Susceptibility of Aeromonas Hydophila Isolates to Antimicrobial Drugs

    Directory of Open Access Journals (Sweden)

    Igor Stojanov

    2010-05-01

    Full Text Available Aeromonas hydrophila is a microorganism widely distributed in nature: in water, soil, food. It is also part of the normal bacterial flora of many animals. As an opportune microorganism it is a secondary biological agent that contributes to the occurrence of a fish disease and its deterioration. Frequently, its presence is an indication of bad zoohygiene and zootechnical conditions in fish ponds. Reduced quality and quantity of feed, mechanical injuries, parasitosis, seasonal oscillation in temperature present some of the factors that produce favorable conditions for bacterial proliferation of aeromonas in fish ponds, so clinical symptoms of the disease occur. Aeromonas is almost always present in clinical isolates and may be unjustly accused for bad health of fish. Antibiotic therapy is applied even when the clinical findings are clear, what certainly effects the susceptibility to chemotherapeutics. The subject of our work was bacteriological examination of the material obtained from the carps with the observed skin changes and the carps without these changes. Also, antimicrobial susceptibility of Aeromonas hydrophila was tested. The aim of this research was to determined the presence of Aeromonas hydrophilia in the carp ponds and to test antibiotic susceptibility. The material consisted of the samples from the fish ponds where the carps were with and without changed skin. The method the isolation of Aeromonas hydrophila was used. The diffusion disk technique was used for testing antibiotic susceptibility. The isolates were tested for their susceptibility to Florephenikol, Flumequine, Olaqindox and Oxitetracycline. The obtained results point that antimicrobial susceptibility was the same regardless of the origin of the samples, i.e. the resistance was the same for both groups of samples (the strains isolated from the fish with skin changes and the strains from fish without changes on skin. The strains were highly resistant: 35% were resistant to

  17. Bactérias do gênero Aeromonas em abatedouro de frangos Contamination by Aeromonas spp. in poultry slaughterhouse

    Directory of Open Access Journals (Sweden)

    F.N. Costa

    2002-10-01

    Full Text Available Analisaram-se 200 amostras de diferentes produtos e locais do fluxograma de abate de frangos com o objetivo de identificar os pontos de contaminação da carne de frango por Aeromonas. Das 25 amostras analisadas para cada um dos oito pontos estudados foram isoladas Aeromonas spp. em nove (36% amostras de penas, em 14 (56% de fezes, em 18 (72% de carcaças não evisceradas, evisceradas e resfriadas e em 20 (80% de água do pré-resfriamento. Não foram isoladas Aeromonas spp. da água de abastecimento da indústria e da água do tanque de escaldagem. Foram identificadas as espécies, Aeromonas hydrophila em 39 (15,2% amostras, A. sobria em 69 (26,9%, A. caviae em 87 (34%, A. veronii em 18 (7%, A. schubertii em três (1,2%, A. trota em duas (0,8% e A. jandaei em uma (0,4%. O resultado sugere que independente do controle higiênico-sanitário adotado na indústria, as carcaças de frangos podem se contaminar já a partir de sua obtenção, determinando o aparecimento de Aeromonas em carcaças resfriadas e prontas para a comercialização.Two hundred samples of poultry meat were analyzed in order to evaluate contamination by Aeromonas spp. in eight sites of a slaughterhouse, with 25 samples obtained in each site. Aeromonas spp. was found in nine (36.0% samples of feathers, 14 (56.0% samples of stools, 18 (72.0% carcasses after pre-evisceration, post-evisceration, and cooling, as well as in 20 (80.0% samples of chilling water. The microorganism was not found in samples from either the supplying water or the tank for scalding water. Aeromonahydrophila was identified in 39 (15.2% samples, whereas A. sobria, A. caviae, A. veronii, A. schubertii, A. trota, and A. jandaei were identified in, respectively, 69 (26.9%, 87 (34.0%, 18 (7.0%, three (1.2%, two (0.8%, and one (0.4% samples. In addition, bacteria dissemination may occur during slaughtering and regardless the hygienic-sanitary control followed by the industry, poultry carcasses may be contaminated

  18. Caracterização de Aeromonas spp isoladas de neonatos hospitalizados Characterization of Aeromonas spp isolates from newborns hospitalized

    OpenAIRE

    2008-01-01

    Aeromonas spp é reconhecida como patogênica para o homem após o consumo de água e alimentos contaminados. Na presente investigação, foram avaliadas 2.323 amostras de swabs retais de neonatos hospitalizados no Rio de Janeiro objetivando o isolamento de Aeromonas. As amostras foram coletadas e enviadas ao Laboratório de Referência Nacional de Cólera e outras enteroinfecções bacterianas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz. Os swabs foram submetidos ao enriquecimento em água peptonada ...

  19. Aeromonas spp. in het Nederlandse drinkwater; een orienterend onderzoek

    NARCIS (Netherlands)

    Versteegh JFM; During M; Havelaar AH; Koot W

    1986-01-01

    In dit rapport worden uitvoering en resultaten van een orienterend onderzoek naar het voorkomen van Aeromonas spp. in het Nederlandse drinkwater in 1985 besproken. Het bleek dat in 71% van de onderzochte monsters (rein water "af pompstation" en water uit het distributienet) in 100 ml gee

  20. SENSITIVITY OF DIFFERENT AEROMONAS SPECIES TO COPPER AND SILVER

    Science.gov (United States)

    Aeromonas bacteria are common flora in surface and ground waters and are considered to be human pathogens. They can also be found in municipally treated drinking water, likely as a component of biofilms, as found in distribution system pipes and point of use water filters. It ...

  1. Characterization of atypical Aeromonas salmonicida by different methods

    DEFF Research Database (Denmark)

    Austin, B.; Austin, D.A.; Dalsgaard, Inger;

    1998-01-01

    Fifty two isolates of atypical Aeromonas salmonicida, recovered from a wide range of hosts and geographical locations, were heterogeneous in terms of molecular and phenotypic characteristics, and represented taxa which could not be accommodated by the current classification of four subspecies...

  2. Production and properties of lipase of Aeromonas sobria.

    Science.gov (United States)

    Takahashi, Eizo; Ito, Hidenobu; Kobayashi, Hidetomo; Yamanaka, Hiroyasu; Takeda, Yoshifumi; Balakrish Nair, Gopinath; Arimoto, Sakae; Negishi, Tomoe; Okamoto, Keinosuke

    2012-05-01

    Aeromonas have been isolated from a wide variety of aquatic environments. However the number of Aeromonas in sea water is extremely small compared to that in fresh water. In in vitro culture, Aeromonas can grow in mediums containing NaCl at a concentration of 3.0%, this concentration corresponding to that of sea water. It is unclear why the number of Aeromonas is low in sea water. Exoproteins of bacteria are thought to be important for bacterial growth and survival in the environment. Previously, the present authors have shown that mediums containing 3.0% NaCl suppress production of two proteases, serine protease and metalloprotease. In this experiment, other exoproteins whose production is influenced by the amount of NaCl in the medium were analyzed. A protein whose production is repressed in medium containing 3.0% NaCl was found and purified. Biological assay of the purified protein showed that it degrades tributyrin and hydrolyzes para-nitrophenyl-fatty acylesters. These results show that the protein is a lipase. Subsequently, the nucleotide sequence of the gene encoding the lipase was determined and the amount of mRNA of the lipase gene in the cells measured. It was found that transcription of the gene is not inhibited by NaCl in the medium. This result indicates that the lipase might be synthesized, but the folding process to become an active structure does not progress smoothly in a medium containing 3.0% NaCl.

  3. Genome Sequence of Hypervirulent Aeromonas hydrophila Strain HZAUAH

    Science.gov (United States)

    Teng, Lin; Deng, Limei; Dong, Xingxing; Wei, Shun; Li, Jinquan

    2017-01-01

    ABSTRACT Aeromonas hydrophila, a zoonotic bacterium found in an expansive range of aquatic ecosystems, has been reported to cause severe diseases in fish, amphibians, reptiles, and mammals, including humans. Herein, we report the draft genome of the hypervirulent A. hydrophila strain HZAUAH isolated from a crucian in China. PMID:28302770

  4. Oral Challenge with Aeromonas in Protein-Malnourished Mice

    Science.gov (United States)

    1994-01-01

    precipitaion after boiling. SRBC. sheep diarrhoea (RITARD) model (25) have red blood cells (hmolysis): Yt. adrenal cell culture; CHO. Chinese hamster...did not seem to affect the susceptibility of mice to deficient substitute for colostrum was not available. Aeromonas spp. infection, but there may be

  5. Clinical implications of species identification in monomicrobial Aeromonas bacteremia.

    Directory of Open Access Journals (Sweden)

    Chi-Jung Wu

    Full Text Available Advances in Aeromonas taxonomy have led to the reclassification of aeromonads. Hereon, we aimed to re-evaluate the characteristics of Aeromonas bacteremia, including those of a novel species, Aeromonas dhakensis.A retrospective study of monomicrobial Aeromonas bacteremia at a medical center in southern Taiwan from 2004-2011 was conducted. Species identification was based on rpoB sequencing. Of bacteremia of 153 eligible patients, A. veronii (50 isolates, 32.7%, A. dhakensis (48, 31.4%, A. caviae (43, 28.1%, and A. hydrophila (10, 6.5% were the principal causative species. A. dhakensis and A. veronii bacteremia were mainly community-acquired and presented as primary bacteremia, spontaneous bacterial peritonitis, or skin and soft-tissue infection, whereas A. caviae was associated with hospital-onset bacteremia. The distribution of the AmpC β-lactamase and metallo-β-lactamase genes was species-specific: bla(AQU-1, bla(MOX, or bla(CepH was present in A. dhakensis, A. caviae, or A. hydrophila, respectively, and bla(CphA was present in A. veronii, A. dhakensis, and A. hydrophila. The cefotaxime resistance rates of the A. caviae, A. dhakensis, and A. hydrophila isolates were higher than that of A. veronii (39.5%%, 25.0%, and 30% vs. 2%, respectively. A. dhakensis bacteremia was linked to the highest 14-day sepsis-related mortality rate, followed by A. hydrophila, A. veronii, and A. caviae bacteremia (25.5%, 22.2%, 14.0%, and 4.7%, respectively; P = 0.048. Multivariate analysis revealed that A. dhakensis bacteremia, active malignancies, and a Pitt bacteremia score ≥ 4 was an independent mortality risk factor.Characteristics of Aeromonas bacteremia vary between species. A. dhakensis prevalence and its associated poor outcomes suggest it an important human pathogen.

  6. The improved PCR of the fstA (ferric siderophore receptor) gene differentiates the fish pathogen Aeromonas salmonicida from other Aeromonas species.

    Science.gov (United States)

    Beaz-Hidalgo, Roxana; Latif-Eugenín, Fadua; Figueras, María José

    2013-10-25

    The members of the genus Aeromonas are autochthonous of aquatic ecosystems and several species have been associated to septicaemia, ulcerative and haemorrhagic diseases in fish, causing significant mortality in both wild and farmed, freshwater and marine fish species. The species Aeromonas salmonicida is generally recognized as the most important fish pathogen responsible for epidemic outbreaks of furunculosis in salmonids, also being able to produce infections in other cultured fish such as turbot, halibut, sea bream or goldfish. New species, i.e. Aeromonas aquariorum, Aeromonas tecta and Aeromonas piscicola, have recently been discovered and isolated from diseased fish. The species A. piscicola and Aeromonas bestiarum are practically impossible to differentiate phenotypically and genetically (when using the 16S rRNA gene) from each other and from A. salmonicida. In the present study, two previously described PCR protocols, based on the fstA and gyrB genes, for the specific detection of A. salmonicida were re-evaluated with the type strains of all Aeromonas species and with a set of A. piscicola and A. bestiarum strains. Contrary to what had been published previously it was demonstrated that the gyrB-PCR is not specific for A. salmonicida because of cross-reactions with other Aeromonas species. However, in agreement with previous results, A. salmonicida was detected on the basis of the fstA-PCR, for which an improved protocol was proposed.

  7. Hemolytic Activity and Siderophore Production in Different Aeromonas Species Isolated from Fish

    OpenAIRE

    Santos, Jesús A.; González, César J.; Otero, Andrés; García-López, María-Luisa

    1999-01-01

    The hemolytic activity and siderophore production of several strains of motile aeromonads were determined. The hemolytic activity of Aeromonas caviae and Aeromonas eucrenophila was enhanced after trypsinization of the samples. The enhancement of hemolysis was observed in strains that carried an aerolysin-like gene, detected by a PCR procedure. Siderophore production was demonstrated in all but one strain of Aeromonas jandaei. No apparent relationship was observed between the presence of plasm...

  8. Antibiotic resistance in Aeromonas upstream and downstream of a water resource recovery facility.

    Science.gov (United States)

    Cisar, Cindy R; Henderson, Samantha K; Askew, Maegan L; Risenhoover, Hollie G; McAndrews, Chrystle R; Kennedy, S Dawn; Paine, C Sue

    2014-09-01

    Aeromonas strains isolated from sediments upstream and downstream of a water resource recovery facility (WRRF) over a two-year time period were tested for susceptibility to 13 antibiotics. Incidence of resistance to antibiotics, antibiotic resistance phenotypes, and diversity (based on resistance phenotypes) were compared in the two populations. At the beginning of the study, the upstream and downstream Aeromonas populations were different for incidence of antibiotic resistance (p resistance phenotypes (p antibiotic resistance in Aeromonas in stream sediments fluctuates considerably over time and (2) suggest that WRRF effluent does not, when examined over the long- term, affect antibiotic resistance in Aeromonas in downstream sediment.

  9. Incidence of Aeromonas bacteremia in Southern Taiwan: vibrio and Salmonella bacteremia as comparators.

    Science.gov (United States)

    Wu, Chi-Jung; Chen, Po-Lin; Tang, Hung-Jen; Chen, Hung-Mo; Tseng, Fan-Chen; Shih, Hsin-I; Hung, Yuan-Pin; Chung, Chih-Huan; Ko, Wen-Chien

    2014-04-01

    The aim of the investigation was to describe the incidence of Aeromonas bacteremia in a city with a population of about 1.87 million inhabitants, located in southern Taiwan, between 2008 and 2010. Such data were compared with the incidences of Vibrio and Salmonella bacteremia in the same period and the incidence of Aeromonas bacteremia in other countries in the literature. The data revealed the average annual incidences of bacteremia due to Aeromonas, Vibrio, and Salmonella species were 76, 38, and 103 cases/million inhabitants, respectively. The incidence of Aeromonas bacteremia was higher than those in Western countries.

  10. Interaction of Aeromonas strains with lactic acid bacteria via Caco-2 cells.

    Science.gov (United States)

    Hatje, E; Neuman, C; Katouli, M

    2014-01-01

    The genus Aeromonas includes some species that have now been identified as human pathogens of significant medical importance. We investigated the ability of 13 selected Aeromonas strains belonging to nine species isolated from clinical cases (n = 5), environmental waters (n = 5), and fish (n = 3) to adhere to and translocate Caco-2 cells in the absence and presence of two lactic acid bacteria (LAB), i.e., Lactobacillus acidophilus and Bifidobacterium breve. Aeromonas isolates were also assessed for their cytotoxicity, the presence of virulence genes, and hemolysin production. Among the clinical isolates, one strain of Aeromonas veronii biovar veronii and two strains of Aeromonas hydrophila carried cytotoxin (act), heat-labile toxin (alt), hemolysin (hlyA), and aerolysin (aerA) genes, were cytotoxic to Vero cells, produced hemolysin, and showed higher adherence to Caco-2 cells. In contrast, this was seen in only one environmental strain, a strain of A. veronii biovar sobria. When Aeromonas strains were coinoculated with LAB onto Caco-2 cells, their level of adhesion was reduced. However, their rate of translocation in the presence of LAB increased and was significantly (P Aeromonas and LAB strains could have a detrimental effect on the Caco-2 cells, allowing the Aeromonas to translocate more readily, or the presence of the LAB stimulated the Aeromonas strains to produce more toxins and/or increase their translocation rate.

  11. Detection of Aeromonas hydrophila Using Fiber Optic Microchannel Sensor

    Directory of Open Access Journals (Sweden)

    Samla Gauri

    2017-01-01

    Full Text Available This research focuses on the detection of Aeromonas hydrophila using fiber optic microchannel biosensor. Microchannel was fabricated by photolithography method. The fiber optic was chosen as signal transmitting medium and light absorption characteristic of different microorganisms was investigated for possible detection. Experimental results showed that Aeromonas hydrophila can be detected at the region of UV-Vis spectra between 352 nm and 354 nm which was comparable to measurement provided by UV spectrophotometer and also theoretical calculation by Beer-Lambert Absorption Law. The entire detection can be done in less than 10 minutes using a total volume of 3 μL only. This result promises good potential of this fiber optic microchannel sensor as a reliable, portable, and disposable sensor.

  12. Evolutionary Roots and Diversification of the Genus Aeromonas

    Science.gov (United States)

    Sanglas, Ariadna; Albarral, Vicenta; Farfán, Maribel; Lorén, J. G.; Fusté, M. C.

    2017-01-01

    Despite the importance of diversification rates in the study of prokaryote evolution, they have not been quantitatively assessed for the majority of microorganism taxa. The investigation of evolutionary patterns in prokaryotes constitutes a challenge due to a very scarce fossil record, limited morphological differentiation and frequently complex taxonomic relationships, which make even species recognition difficult. Although the speciation models and speciation rates in eukaryotes have traditionally been established by analyzing the fossil record data, this is frequently incomplete, and not always available. More recently, several methods based on molecular sequence data have been developed to estimate speciation and extinction rates from phylogenies reconstructed from contemporary taxa. In this work, we determined the divergence time and temporal diversification of the genus Aeromonas by applying these methods widely used with eukaryotic taxa. Our analysis involved 150 Aeromonas strains using the concatenated sequences of two housekeeping genes (approximately 2,000 bp). Dating and diversification model analyses were performed using two different approaches: obtaining the consensus sequence from the concatenated sequences corresponding to all the strains belonging to the same species, or generating the species tree from multiple alignments of each gene. We used BEAST to perform a Bayesian analysis to estimate both the phylogeny and the divergence times. A global molecular clock cannot be assumed for any gene. From the chronograms obtained, we carried out a diversification analysis using several approaches. The results suggest that the genus Aeromonas began to diverge approximately 250 millions of years (Ma) ago. All methods used to determine Aeromonas diversification gave similar results, suggesting that the speciation process in this bacterial genus followed a rate-constant (Yule) diversification model, although there is a small probability that a slight

  13. Aeromonas spp.: evaluation of genomic diversity and biofilm forming ability

    OpenAIRE

    Craveiro, Sara Sofia Pereira, 1986-

    2013-01-01

    Tese de mestrado. Biologia (Microbiologia Aplicada). Universidade de Lisboa, Faculdade de Ciências, 2013 Aeromonas spp. are ubiquitous bacteria widely distributed among aquatic environments. Their persistence in water distribution systems is related to their ability to form biofilms, even in the presence of residual chlorine. Once in distribution water systems, aeromonads can contaminate drinking water, food processing facilities and food products. Moreover, members of this genus are known...

  14. Clinical and biochemical significance of toxin production by Aeromonas hydrophila.

    Science.gov (United States)

    Kindschuh, M; Pickering, L K; Cleary, T G; Ruiz-Palacios, G

    1987-05-01

    Production of cytotoxin and enterotoxin by Aeromonas strains obtained from stools of 50 children in Mexico and Texas and from blood of 9 children with sepsis was determined. Results were correlated with clinical features of infected children as well as with biochemical traits of Aeromonas strains. Cytotoxin was produced by 40 of 42 Aeromonas strains (95%) isolated from stools of children with diarrhea, by all 8 isolates from stools of well children, and by all 9 isolates from children with sepsis. There was no difference in the quantities (amount of cytotoxin per milligram of protein required to kill 50% of the cells) of cytotoxin produced and in clinical manifestations among the groups. None of the isolates produced a toxin that could be neutralized by antiserum raised against Shiga toxin produced by Shigella dysenteriae 1 60R. Heat-labile-like enterotoxin (LT) was produced by 26 of 42 stool isolates (62%), while only 1 of the 42 isolates (2%) produced enterotoxinlike activity in suckling mice; 65% of the cytotoxin-producing strains also produced an LT-like material. All strains from blood produced LT-like material, and 2 of 6 (33%) produced activity in suckling mice. All strains produced hemolysin; 37 of 57 (65%) were Voges-Proskauer positive; 27 of 57 (47%) were lysine decarboxylase positive by API 20E strips, none were positive for lysine decarboxylose production by lysin-iron agar slants at 24 h, but 17 of 54 (31%) were positive at 48 h. There was no correlation between biochemical reactions and enterotoxin or cytotoxin production. There appears to be no correlation between toxin production by Aeromonas spp. and gastroenteritis.

  15. Screening and Characterization of a Bioflocculant Produced by Aeromonas sp.

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To isolate the bioflocculant-producing bacteria from activated sludge and investigate the flocculating characteristics of the newly isolated bioflocculant. Methods Bacteria were screened from activated sludge samples to isolate bioflocculant-producing bacteria. Flocculating activity was used as a measure of the flocculating capability of the bioflocculant.Results A novel bioflocculant-producing bacterium was isolated, which was identified to belong to genus Aeromonas and named as Aeromonas sp. N11. Flocculating activity increased in the presence of K+, Na+, or Ca2+. The highest flocculating activities for kaolin suspension were obtained in acidic pH ranges, and optimum pHs for it were 3.0, 4.0, and 5.0 with 1 mmol/L K+, Ca+, and Na+ present, respectively. The highest flocculating activities for soil suspension were observed at pH 8.0. The bioflocculant had a good flocculating activity and could achieve a flocculating activity of 92.4% for kaolin suspension at a Conclusion The bioflocculant produced by Aeromonas sp. N11 has strong flocculating activity and high stability, which affords high possibility of its practical use.

  16. Biological control of Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) using Aeromonas phage PAS-1.

    Science.gov (United States)

    Kim, J H; Choresca, C H; Shin, S P; Han, J E; Jun, J W; Park, S C

    2015-02-01

    The potential control efficacy of Aeromonas phage PAS-1 was evaluated against Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) model in this study. The phage was co-cultured with the virulent A. salmonicida subsp. salmonicida strain AS05 that possesses the type III secretion system (TTSS) ascV gene, and efficient bacteriolytic activity was observed against the bacteria. The administration of PAS-1 in rainbow trout demonstrated that the phage was cleared from the fish within 200 h post-administration, and a temporal neutralizing activity against the phage was detected in the sera of phage-administrated fish. The administration of PAS-1 (multiplicity of infection: 10 000) in A. salmonicida subsp. salmonicida infected rainbow trout model showed notable protective effects, with increased survival rates and mean times to death. These results demonstrated that Aeromonas phage PAS-1 could be considered as an alternative biological control agent against A. salmonicida subsp. salmonicida infections in rainbow trout culture.

  17. Chitin degradation and utilization by virulent Aeromonas hydrophila strain ML10-51K

    Science.gov (United States)

    Virulent Aeromonas hydrophila (vAh) is one of the most important bacterial pathogens that causes persistent outbreaks of motile Aeromonas septicemia (MAS) in warm-water fishes. Among factors associated with MAS outbreaks, the survivability of this pathogen in aquatic environments is of great concern...

  18. Complete genome sequence of channel catfish epidemic isolate Aeromonas hydrophila ML09-119

    Science.gov (United States)

    Aeromonas hydrophila is a Gram-negative, rod-shaped, mesophilic bacteria that infects both aquatic poikilothermic animals and mammals, including humans. Here, we present the complete genome sequence of Aeromonas hydrophila ML-09-119, which represents a clonal group of A. hydrophila isolates causing ...

  19. Aeromonas hydrophila urinary tract infection in pregnancy- Case report and literature review

    Directory of Open Access Journals (Sweden)

    Latha Ragunathan

    2012-03-01

    Full Text Available A case of a pregnant woman without previous or concomitant disease, who developed an Aeromonas hydrophila urinarytract infection (UTI at 12 weeks gestation, is reported. A brief review of the literature on the association and incidenceof Aeromonas spp in urinary infections and also in association with pregnancy is presented. J Microbiol Infect Dis 2012;2(1: 26-28

  20. Classification of a hypervirulent Aeromonas hydrophila pathotype responsible for epidemic outbreaks in warm-water fishes

    Science.gov (United States)

    Lineages of hypervirulent Aeromonas hydrophila (vAh) are the cause of persistent outbreaks of motile Aeromonas septicemia in warm-water fishes worldwide. Over the last decade, this virulent lineage of A. hydrophila has resulted in annual losses of millions of tons of farmed carp and catfish in the P...

  1. Diarrea del viajero asociada a Aeromonas hydrophila Traveller's diarrohea caused by Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    M. L. Pita Toledo

    2001-06-01

    Full Text Available Aeromonas hydrophila es una bacteria que se encuentra frecuentemente en aguas dulces y salobres. Desde hace varios años se conoce que determinadas cepas de la especie pueden causar enfermedad en pescados y en anfibios, existiendo cierta controversia sobre su patogeneicidad en humanos. No obstante, puede dar lugar a infección en personas, que la adquieren bien a través de heridas abiertas o bien por ingestión de alimentos o agua contaminados. Sin embargo, en prácticamente la totalidad de las publicaciones se hace referencia a casos aislados más que a brotes producidos por esta bacteria. Generalmente la infección por A. hydrophila da lugar a gastroenteritis en personas sanas, pudiendo generar una septicemia en individuos inmunodeprimidos.En 1998 se produjo una alarma en el sector hotelero por un incremento considerable de los casos de gastroenteritis entre los turistas que acudían durante sus vacaciones a determinadas zonas costeras de la isla de Tenerife.Tras tener conocimiento de la situación, la Dirección General de Salud Pública inició una investigación epidemiológica con el objetivo de conocer la magnitud real del problema detectado e identificar los factores asociados a la misma, para poner en marcha las medidas correctoras y de control necesarias. El análisis inicial permitió determinar que se trataba de un proceso de gran magnitud en su extensión aunque de carácter leve, que afectaba únicamente a los turistas en una zona costera en concreto, compatible por lo tanto con la diarrea del viajero, planteándose un origen probablemente hídrico.Aeromonas hydrophila is a bacteria frequently found in fresh water and saline water. Certain strains of the species have been known to cause disease in fish and amphibians for several years, although some controversy exists about its ability to cause illness in humans. Nevertheless, either through open wounds or contaminated food or water, it can give rise to infection. However, almost

  2. Aeromonas detection and characterization using genus-specific PCR and single-strand conformation polymorphism (SSCP).

    Science.gov (United States)

    Delamare, Ana Paula Longaray; Lucena, Roberto Francisco; Thomazi, Guilherme; Ferrarini, Shana; Zacaria, Jucimar; Echeverrigaray, Sergio

    2012-10-01

    Based on sequence alignment, oligonucleotide primers targeting the Aeromonas extracellular lipase gene were developed for PCR detection of member of the genus. A pair of primers designed for conserved regions of the gene amplified a 276 bp sequence in all Aeromonas species and tested strains, but did not have a positive result with other Gram-positive and Gram-negative bacteria, showing high specificity and sensitivity. Selective enrichment in alkaline peptone water, followed by centrifugation, and direct usage of cells suspension as template, detected initial populations of 10 c.f.u. ml⁻¹. Single-strand conformation polymorphism analysis of the PCR products allowed the characterization of Aeromonas strains with a high discriminatory power (Simpson's index = 0.988). The method presented here provides a useful tool for the rapid detection of Aeromonas and the characterization of Aeromonas isolates.

  3. Genome sequencing and annotation of Aeromonas sp. HZM

    Directory of Open Access Journals (Sweden)

    Patric Chua

    2015-09-01

    Full Text Available We report the draft genome sequence of Aeromonas sp. strain HZM, isolated from tropical peat swamp forest soil. The draft genome size is 4,451,364 bp with a G + C content of 61.7% and contains 10 rRNA sequences (eight copies of 5S rRNA genes, single copy of 16S and 23S rRNA each. The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. JEMQ00000000.

  4. Effect of solar irradiation on extracellular enzymes of Aeromonas proteolytica

    Science.gov (United States)

    Foster, B. G.

    1973-01-01

    The bacterium Aeromonas proteolytica was selected for studying the effects of solar irradiation on extracellular enzymes because it produces an endopeptidase that is capable of degrading proteins and a hemolysin that is active in lysing human erythrocytes. Possible alterations in the rate of enzyme production in response to the test conditions are currently underway and are not available for this preliminary report. Completed viability studies are indicative that little difference exists among the survival curves derived for cells exposed to various components of ultraviolet irradiation in space.

  5. Use of Aeromonas as a process indicator during swine carcass dressing and cutting

    Science.gov (United States)

    Palumbo, Samuel A.; Yu, Linda S. L.

    1999-01-01

    Using starch ampicillin agar, qualitative and quantitative determinations of Aeromonas spp. were made at several sites during swine carcass dressing and cutting. Aeromonas spp. were observed at all sites surveyed. Levels increased during shackling and passage through the first and middle polisher/washers, and significantly decreased during the singeing steps. Passage through the final polisher/washer caused a small increase in levels in Aeromonas spp. and these levels then remained constant during the rest of the carcass dressing operation. Aeromonas spp. were also isolated from the room where the carcasses were cut into wholesale cuts and cuts for further processing. Presumptive Aeromonas spp. cultures isolated from the different sites were confirmed as belonging to the genus Aeromonas and then speciated using the biochemical scheme of Joseph and Carnahan; 81% of the cultures were identified at A. hydrophila. Since most isolates were A. hydrophila, determination of the origin of isolates from different sites in the processing plant must await utilizing molecular biotyping techniques on the cultures. These results indicate the Aeromonas spp. occurs extensively in the swine dressing environment and thus represents a possible public health hazard and potential spoilage concern. Changes in cleaning and sanitizing of equipment may be necessary during swine carcass dressing and cutting to guard against this pathogen.

  6. Detection of antibiotic resistance, virulence gene determinants and biofilm formation in Aeromonas species isolated from cattle.

    Science.gov (United States)

    Igbinosa, Isoken H; Igbinosa, Etinosa O; Okoh, Anthony I

    2015-11-01

    This study aimed to assess the antibiogram of Aeromonas strains recovered from cattle faeces and the potential pathogenic status of the isolates. The antibiogram of the Aeromonas isolates demonstrated total resistance to clindamycin oxacillin, trimethoprim, novobiocin and ticarcillin. However, Aeromonas strains were sensitive to cefotaxime, oxytetracycline and tobramycin. The Aeromonas strains from Lovedale and Fort Cox farms were found to possess some virulence genes. The percentage distribution was aer 71.4%, ast 35.7%, fla 60.7%, lip 35.7% and hlyA 25% for Lovedale farm and aer 63.1%, alt 10.5%, ast 55.2%, fla 78.9%, lip 21% and hlyA 35.9% for Fort Cox farm. Class 1 integron was present in 27% of Aeromonas isolates; the bla TEM gene was present in 34.8%, while the blaP1 class A β-lactamase gene was detected in 12.1% of the isolates. Approximately 86% of the isolates formed a biofilm on microtitre plates. The presence of multiple antibiotic resistance and virulence genes in Aeromonas isolates from cattle faeces reveals the pathogenic and infectious importance of these isolates and is of great significance to public health. The possession of a biofilm-forming capability by such isolates may lead to difficulty during the management of infection related to Aeromonas species.

  7. [AEROMONAS BACTERIA ISOLATED FROM BITHYNIIDAE MOLLUSKS AND THEIR HABITATS: SPECIES COMPOSITION AND BIOLOGICAL PROPERTIES. COMMUNICATION 1].

    Science.gov (United States)

    Stepanova, T F; Bukharin, O V; Kataeva, L V; Perunova, N B; Karpukhina, N F

    2015-01-01

    The purpose of this investigation was to study the species composition and biological properties of Aeromonas bacteria isolated from Bithyniidae mollusks and their habitat (a water reservoir). The Bithyniidae mollusks and water from their habitat were the material to be studied. A total of 176 Aeromonas strains were isolated from the mollusks and water. A. veronii, A. hydrophila, and A. ichthiosmia were most common in the mollusks and A. veronii and A. ichthiosmia were in the water. All the strains isolated had hemolytic activity and no lysozyme or plasma coagulase activity. The magnitude of lecithinase and antilysozymic activities and biofilm formation of the Aeromonas bacteria varied with the isolation source of their strains.

  8. Lippia alba essential oil promotes survival of silver catfish (Rhamdia quelen) infected with Aeromonas sp.

    OpenAIRE

    FERNANDO J. SUTILI; Cunha,Mauro A.; Rosangela E. Ziech; Krewer,Carina C.; CARLA C. ZEPPENFELD; Heldwein, Clarissa G.; Gressler, Leticia T.; Berta M. Heinzmann; Agueda C. de Vargas; BERNARDO BALDISSEROTTO

    2015-01-01

    In vitro and in vivo activity of the Lippia alba essential oil (EO) against Aeromonas sp. was evaluated. In the in vitro assay the minimum inhibitory concentration (MIC) and a minimum bactericidal concentration (MBC) of EO for Aeromonas cells were determined using the microdilution method. Twenty five strains of Aeromonas sp. isolated from infected fish obtained from local fish farms were used. MIC and MBC values were 2862 and 5998 µg mL-1 for L. alba EO and 0.5 and 1.2 µg mL-1 for ...

  9. Incidence and toxigenicity of Aeromonas hydrophila in seafood.

    Science.gov (United States)

    Tsai, G J; Chen, T H

    1996-08-01

    Three selective media, Oxoid Aeromonas agar (OA), blood ampicillin agar (BA) and starch ampicillin agar (SA) were used to evaluate the presence of Aeromonas hydrophila in 66 samples of oyster, shrimp, fish and surimi products. Oyster had the highest incidence, with 50% positive, whilst no A. hydrophila was found in the surimi. Of the three selective media, BA displayed the highest recovery rate of A. hydrophila from seafood. Forty-eight isolates from this survey were tested for their capability to produce hemolysin and cytotoxin. Hemolysin was produced by 79.2% of the isolates and cytotoxin was produced by 91.7% of the isolates in brain heart infusion broth. One of the toxin-producing isolates from oyster, strain 8-169, was further tested for growth and toxin production in oyster, shrimp and fish at various temperatures. This particular isolate grew best and had highest toxin production in oyster. Hemolysin and cytotoxin were produced earlier at 28 degrees C than at 37 degrees C, and titers of hemolysin were also higher at 28 degrees C. At 5 degrees C, it was able to grow and produce hemolysin in oyster.

  10. Genotypic and phenotypic identification of Aeromonas species and CphA-mediated carbapenem resistance in Queensland, Australia.

    Science.gov (United States)

    Sinclair, Holly A; Heney, Claire; Sidjabat, Hanna E; George, Narelle M; Bergh, Haakon; Anuj, Snehal N; Nimmo, Graeme R; Paterson, David L

    2016-05-01

    Infection caused by Aeromonas spp. ranges from superficial wound infection to life-threatening septicemia. Carbapenem resistance due to metallo-beta-lactamase, CphA encoded by the cphA gene, is a significant problem. This study defines Aeromonas spp. causing clinical disease in Queensland, Australia. Phenotypic tests for carbapenemase detection were assessed. One hundred Aeromonas isolates from blood (22), wound (46), sterile sites (11), stool (18), eye (2), and sputum (1) were characterized by rpoB and gyrB sequencing. Meropenem susceptibility by VITEK2, disk diffusion, and E-test MIC were determined. Carbapenemase production was assessed by Carba NP test and cphA by PCR. Gene sequencing identified isolates as Aeromonas dhakensis (39), Aeromonas veronii (21), Aeromonas hydrophila (20), Aeromonas caviae (14), Aeromonas jandaei (4), Aeromonas bestiarum (1), and Aeromonas sanarellii (1). Disk diffusion and E-test failed to detect resistance in isolates with presence of cphA. Carba NP was performed with 97.4% sensitivity and 95.7% specificity. Carbapenem resistance gene cphA was detected in A. veronii (21; 100%), A. hydrophila (18; 90%), A. dhakensis (34; 87.2%), A. jandaei (3; 75%), and A. bestiarum (1; 100%) but not A. caviae. We found that A. dhakensis was the predominant species, a previously unrecognized pathogen in this region.

  11. A comparative study of clinical Aeromonas dhakensis and Aeromonas hydrophila isolates in southern Taiwan: A. dhakensis is more predominant and virulent.

    Science.gov (United States)

    Chen, P-L; Wu, C-J; Chen, C-S; Tsai, P-J; Tang, H-J; Ko, W-C

    2014-07-01

    Aeromonas dhakensis, often phenotypically identified as Aeromonas hydrophila, is an important human pathogen. The present study aimed to compare the clinical and biological features of A. dhakensis and A. hydrophila isolates from human wounds. A total of 80 Aeromonas wound isolates collected between January 2004 and April 2011 were analysed. The species was identified by the DNA sequence matching of rpoD and gyrB (or rpoB if necessary). Most of the Aeromonas isolates were identified as A. dhakensis (37, 46.3%), and 13 (16.3%) as A. hydrophila. Both species alone can cause severe skin and soft-tissue infections. More A. dhakensis isolates were found in wounds exposed to environmental water (32.4% vs 0%, p 0.042). More biofilm formation was noted among A. dhakensis isolates (mean optical density at 570 nm, 1.23 ± 0.09 vs 0.78 ± 0.21, p 0.03). The MICs of ceftriaxone, imipenem and gentamicin for A. dhakensis isolates were higher (p Aeromonas wound isolates, and more virulent than A. hydrophila.

  12. Draft genome sequences of three Aeromonas hybrophila isolates from catfish and tilapia

    Science.gov (United States)

    Aeromonas hydrophila is a Gram-negative bacteria that is particularly adapted to freshwater environments and can cause severe infections in fish and humans. Here we report the draft genomes of three A. hydrophila catfish and tilapia isolates....

  13. HOST GENE CELL RESEARCH FOR DETERMINING VIRULENCE OF AEROMONAS SPP. COLLECTED FROM ENVIRONMENTAL SAMPLES

    Science.gov (United States)

    The United States Environmental Protection Agency (USEPA) is interested in assessing health risks associated with emerging or potential waterborne pathogens. To this end, the Agency has established a Candidate Contaminant List (CCL) that includes Aeromonas hydrophila an...

  14. IDENTIFICATION AND CHARACTERIZATION OF AEROMONAS ISOLATES FROM DRINKING WATER DISTRIBUTION SYSTEMS

    Science.gov (United States)

    Members of the bacterial genus Aeromonas are commonly isolated from both fresh and salt waters worldwide and some are believed to cause infections in humans, including gastroenteritis and wound infections. Currently, aeromonads are on the United States Environmental Protection A...

  15. Aeromonas hydrophila meningitis and fulminant sepsis in preterm newborn: A case report and review of literature

    Directory of Open Access Journals (Sweden)

    A Kali

    2016-01-01

    Full Text Available Neonatal meningitis is a lethal infection occurring in the 1st month of life. The risk of developing permanent neurological sequels is high among the neonates who survive. Bacterial pathogens are commonly associated with this condition. Aeromonas is a Gram-negative bacteria of aquatic habitat. Although isolation of Aeromonas species from neonates with blood stream infection is infrequently reported, neonatal meningitis caused by Aeromonas is exceedingly rare. We present a case of fulminant sepsis and meningitis caused by Aeromonas hydrophila in a preterm newborn male. The bacteria was isolated in culture from blood and cerebrospinal fluid. In spite of targeted antibiotics and supportive therapy, the baby failed to respond and died on the 12th day of life.

  16. Anti-biogram and resistogram profiling of Aeromonas species isolated from Malaysian aquatic sources

    OpenAIRE

    Olumide Adedokun Odeyemi; Asmat Ahmad

    2013-01-01

    Objective: To investigate antibiotics and heavy metals resistance profile of Aeromonas species isolated from Kuala Gula and Kuala Sepetang, Perak. Methods: Isolated Aeromonas species were subjected to 12 antibiotics: penicillin G 10 units, tetracycline 30 µg, novobiocin 5 µg, nitrofurantoin 100 µg, ampicillin 10 µg, chloramphenicol 10 µg, fluconazole 25 µg, gentamicin 10 µg, streptomycin 10 µg and 25 µg, kanamycin 30 µg, and vancomycin 30 µg and 5 heavy metals: MnSO4.H2O, Cr(NO...

  17. Correlation of the Suicide Phenomenon in Aeromonas Species with Virulence and Enteropathogenicity

    OpenAIRE

    1989-01-01

    Certain strains of mesophilic aeromonads (Aeromonas hydrophila, A. sorbria, and A. caviae), when grown in broth containing 0.5% glucose, undergo growth inhibition concomitant with acetate accumulation. Because these strains are nonviable after 24 h, this phenomenon is termed suicide. We investigated suicidal strains of Aeromonas species as a means of understanding animal virulence and enteropathogenicity. To assess virulence, batches of five white mice were inoculated intraperitoneally with 1...

  18. Isolation and Seroprevalence of Aeromonas spp. Among Common Food Animals Slaughtered in Nagpur, Central India.

    Science.gov (United States)

    Gowda, Tanuja K G M; Reddy, Vishwanatha R A P; Devleesschauwer, Brecht; Zade, Nandkishor N; Chaudhari, Sandeep P; Khan, Waqar A; Shinde, Shilpa V; Patil, Archana R

    2015-07-01

    Aeromonads are ubiquitous foodborne pathogens with a global distribution. Animal-origin foods and contaminated animals are the main sources of Aeromonas infection to humans. So far little is known about the occurrence of Aeromonas spp. in food-producing animals in India. The present study was conducted to determine the prevalence and seroprevalence of Aeromonas species from 50 each of meat, blood, and sera samples collected from cattle, buffaloes, goats, and pigs slaughtered in and around Nagpur, Central India. Alkaline peptone water and ampicillin dextrin agar were used to isolate Aeromonas spp. An indirect enzyme-linked immunosorbent assay (ELISA) was standardized by use of whole-cell antigen (WC) and outer membrane protein (OMP) of Aeromonas hydrophila (MTCC 646). Aeromonads were isolated from 44 (22%) of the meat samples, and 1 (0.5%) from the blood samples. Seroprevalence by indirect ELISA-based WC antigen was estimated as 68% in cattle, 44% in buffaloes, 60% in goats, and 30% in pigs. OMP-based ELISA yielded a seroprevalence of 56%, 48%, 52%, and 22% in cattle, buffaloes, goats, and pigs, respectively. The results revealed that OMP-based ELISA and WC-based ELISA were in agreement with one another. Isolation along with high seropositivity demonstrates the presence of foodborne Aeromonas spp. in the Nagpur city of Central India.

  19. High frequency of coinfecting enteropathogens in Aeromonas-associated diarrhea of hospitalized Peruvian infants.

    Science.gov (United States)

    Pazzaglia, G; Sack, R B; Salazar, E; Yi, A; Chea, E; Leon-Barua, R; Guerrero, C E; Palomino, J

    1991-06-01

    Rectal swabs from 391 infants less than 18 months of age who were hospitalized with acute diarrhea and from 138 similarly aged healthy infants were examined for the etiologic agents of diarrhea. Aeromonas spp. were recovered from 205 of 391 (52.4%) diarrheic patients, whereas they were recovered from 12 of 138 (8.7%) controls (P less than 10(-11). Among the 205 Aeromonas-positive diarrheic patients, 118 (57.6%) were found to be coinfected with other common enteropathogens. Of the 164 Aeromonas-positive initial diarrheic specimens, 82 (50.0%) had one or more other enteropathogens present; 30 patients were coinfected with rotavirus, 20 with enterotoxigenic Escherichia coli, 16 with Campylobacter spp., 14 with Shigella spp., 13 with enteropathogenic E. coli, 4 with Vibrio spp., 1 with Salmonella spp., and 1 with Plesiomonas spp. of Aeromonas strains from cases compared with that from controls supports an etiologic role for this organism. However, frequent concomitant infections with other well-recognized enteropathogens and a lack of disease correlation with common Aeromonas phenotypes suggest that only a subset of Aeromonas strains may be diarrhea causing and that such strains may be common to several of the existing species.

  20. Mortality of therapeutic fish Garra rufa caused by Aeromonas sobria

    Institute of Scientific and Technical Information of China (English)

    Juraj Majtn; Jaroslaverny; Alena Ofkan; Peter Tak; Milan Koznek

    2012-01-01

    Objective:To investigate a case of mass mortality of Garra rufa (G. rufa) from a fish hatchery farm in Slovakia. Methods: Causative bacterial agent was swabbing out of affected fish skin area and subsequently identified using commercial test system. Antibiotic susceptibility was determined by the disk diffusion method. Results: Infected G. rufa was characterized by abnormal swimming behaviour, bleeding of skin lesions and local haemorrhages. Despite of using recommended aquatic antibiotic treatment no improvement was achieved and Aeromonas sobria (A. sobria) was identified as a causative agent of fish mortality. Due to massive fish mortality, antibiotic susceptibility of pure isolated culture of A. sobria was evaluated employing eight antibiotics against human infections. A. sobria was resistant only against one antibiotic, namely ampicilin. Conclusions: These results indicate that A. sobria can act as a primary pathogen of G. rufa and may be a potential risk factor for immunodeficient or immunoincompetent patients during the ichthyotherapy.

  1. Isolation of Aeromonas hydrophila from the American alligator, Alligator mississippiensis

    Energy Technology Data Exchange (ETDEWEB)

    Gorden, R.W. (Univ. of Southern Colorado, Pueblo); Hazen, T.C.; Esch, G.W.; Fliermans, C.B.

    1979-04-01

    Aeromonas hydrophila was isolated from the internal organs of nine adult alligators, Alligator mississippiensis, which died without apparent cause, suggesting the bacterium may have been a factor. One hundred and twenty-three alligators ranging in age from six months to over 10 years were captured from five locations in the southeastern United States and sampled for A. hydrophila. The bacterium was isolated from the oral cavity of 85% of the animals, on the external jaw area from over 50% and from 70% of the internal tissue samples. A. hydrophila is ubiquitous with alligators in their natural habitats, but apparently does not cause clinical disease. However, stress factors such as trapping, handling, and warm water tempertures may be conducive to the rapid proliferation of the bacteria, thereby facilitating disease.

  2. 气单胞菌和嗜水气单胞菌双重PCR检测方法的建立%Development of a duplex PCR for detection of Aeromonas spp.and Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    潘晓艺; 沈锦玉; 郝贵杰; 姚嘉贇; 徐洋; 尹文林; 孙逢明; 吴颖蕾

    2011-01-01

    Aeromonas is one of the major pathogens which frequently cause the bacterial diseases in freshwater fish terrapin and crustaceans. Aeromonas hydrophila caused economic losses widely. In order to detect Aeromonas spp. And Aeromonas hydrophila, two pairs of specific primers were designed according to the glycerophospholipid-cholesterol acyltransferase (GCAT) gene of Aeromonas spp. And the 16S rRNA gene of Aeromonas hydrophila. So a duplex PCR assay was developed to amplify the 16S rRNA gene and the GCAT gene. The reaction conditions of the duplex PCR were optimized and PCR products were sequenced. Meanwhile, the specificity of duplex PCR was studied. Five Aeromonas hydrophila strains,seven Aeromonas strains and the other five strains of non Aeromonas were tested by duplex PCR. The results showed that the GCAT gene and the 16S rRNA gene could be amplified from Aeromonas hydrophila strains,but only the GCAT gene from the other Aeromonas species and neither from the other five strains. It could be concluded that the duplex PCR was specific and could be used in quick diagnose Aeromonas hydrophila and Aeromonas spp.%针对GenBank中登录的气单胞菌属(Aeromonas)的毒力基因甘油磷脂胆固醇酰基转移酶基因(GCA T)和嗜水气单胞菌(Aeromonash ydrophila)的16S rRNA基因的保守区设计2对特异性引物.通过进行双重PCR反应体系优化,PCR产物的测序鉴定和特异性试验,建立了一种能同时检测气单胞菌(Aeromonas spp.)和嗜水气单胞菌的双重PCR检测方法.用此方法对5株嗜水气单胞菌、7株其他不同种的气单胞菌和5株非气单胞菌属菌株进行双重PCR检测.结果显示,气单胞菌和嗜水气单胞菌在GCAT基因的扩增区都能得到有效扩增,其中嗜水气单胞菌能同时在16S rRNA基因扩增区得到有效扩增,而非气单胞菌属的菌株,在此两扩增区都为阴性,表明此检测方法可靠且可行.

  3. Occurrence of motile Aeromonas in municipal drinking water and distribution of genes encoding virulence factors.

    Science.gov (United States)

    Pablos, Manuel; Rodríguez-Calleja, Jose M; Santos, Jesús A; Otero, Andrés; García-López, María-Luisa

    2009-10-31

    Aeromonas-associated cases of gastroenteritis are generally considered waterborne. The purpose of this study was to evaluate the potential microbiological risk associated with the presence of these bacteria in public drinking water. Over a period of one year, 132 drinking-water samples were monitored in León (NW of Spain, 137,000 inhabitants) for mandatory drinking-water standards and the occurrence of Aeromonas spp. Samples were taken at the municipal water treatment plant, one storage facility, and two public artesian drinking-water fountains. Because of low numbers of coliforms or Clostridium perfringens, the non-compliance rate with microbial standards was 3.8% whereas the percentage of positive samples for motile mesophilic Aeromonas was 26.5%. For all but two samples, Aeromonas was recovered between October and early March when the temperature was below 14 degrees C and the residual chlorine ranged from 0.21 to 0.72 mg/l. An apparent relationship was observed between rainfall and the incidence of Aeromonas. The 35 selected Aeromonas isolates were identified as A. caviae and A. media. The alt and laf genes were present in all isolates, the aerA gene was present in six isolates, and the four remaining genes investigated (hlyA, ast, stx1 and stx2) were absent. The combinations of putative virulence genes were: aerA(-)/hlyA(-)/alt(+)/ast(-)/laf(+)/stx1(-)/stx2(-) (82.9%) and aerA(+)/hlyA(-)/alt(+)/ast(-)/laf(+)/stx1(-)/stx2(-) (17.1%). None of the isolates bore plasmids. As Aeromonas strains harbouring two or more virulence-associated genes have the potential to cause disease by direct transmission via drinking water or by water use in food preparation, it would be advisable to control excessive numbers of these bacteria in drinking-water supplies.

  4. Identification of clinical aeromonas species by rpoB and gyrB sequencing and development of a multiplex PCR method for detection of Aeromonas hydrophila, A. caviae, A. veronii, and A. media.

    Science.gov (United States)

    Persson, Søren; Al-Shuweli, Suzan; Yapici, Seval; Jensen, Joan N; Olsen, Katharina E P

    2015-02-01

    Conventional identification of Aeromonas species based on biochemical methods is challenged by the heterogeneous nature of the species. Here, we present a new multiplex PCR method directed toward the gyrB and rpoB genes that identifies four Aeromonas species, A. hydrophila, A. media, A. veronii, and A. caviae, and we describe the application of this method on a Danish strain collection.

  5. Identification and molecular characterization of the homogentisate pathway responsible for pyomelanin production, the major melanin constituents in Aeromonas media WS.

    Directory of Open Access Journals (Sweden)

    He Wang

    Full Text Available The pigmentation of many Aeromonas species has been thought to be due to the production of a L-DOPA (L-3,4-dihydroxyphenylalanine based melanin. However, in this study we found that although L-DOPA synthesis occurs in the high-melanin-yielding Aeromonas media strain WS, it plays a minor, if any, role in pigmentation. Instead, the pigmentation of A. media strain WS is due to the production of pyomelanin through HGA (homogentisate. Gene products of phhA (encodes phenylalanine hydroxylase, tyrB and aspC (both encode aromatic amino acid aminotransferase, and hppD (encodes 4-hydroxyphenylpyruvate dioxygenase constitute a linear pathway of converting phenylalanine to HGA and disruption of any one of these genes impairs or blocks pigmentation of A. media strain WS. This HGA biosynthesis pathway is widely distributed in Aeromonas, but HGA is only detectable in the cultures of pigmented Aeromonas species. Heterologous expression of HppD from both pigmented and non-pigmented Aeromonas species in E. coli leads to the production of pyomelanin and thus pigmentation, suggesting that most Aeromonas species have the critical enzymes to produce pyomelanin through HGA. Taken together, we have identified a widely conserved biosynthesis pathway of HGA based pyomelanin in Aeromonas that may be responsible for pigmentation of many Aeromonas species.

  6. Identification and molecular characterization of the homogentisate pathway responsible for pyomelanin production, the major melanin constituents in Aeromonas media WS.

    Science.gov (United States)

    Wang, He; Qiao, Yunqian; Chai, Baozhong; Qiu, Chenxi; Chen, Xiangdong

    2015-01-01

    The pigmentation of many Aeromonas species has been thought to be due to the production of a L-DOPA (L-3,4-dihydroxyphenylalanine) based melanin. However, in this study we found that although L-DOPA synthesis occurs in the high-melanin-yielding Aeromonas media strain WS, it plays a minor, if any, role in pigmentation. Instead, the pigmentation of A. media strain WS is due to the production of pyomelanin through HGA (homogentisate). Gene products of phhA (encodes phenylalanine hydroxylase), tyrB and aspC (both encode aromatic amino acid aminotransferase), and hppD (encodes 4-hydroxyphenylpyruvate dioxygenase) constitute a linear pathway of converting phenylalanine to HGA and disruption of any one of these genes impairs or blocks pigmentation of A. media strain WS. This HGA biosynthesis pathway is widely distributed in Aeromonas, but HGA is only detectable in the cultures of pigmented Aeromonas species. Heterologous expression of HppD from both pigmented and non-pigmented Aeromonas species in E. coli leads to the production of pyomelanin and thus pigmentation, suggesting that most Aeromonas species have the critical enzymes to produce pyomelanin through HGA. Taken together, we have identified a widely conserved biosynthesis pathway of HGA based pyomelanin in Aeromonas that may be responsible for pigmentation of many Aeromonas species.

  7. AQU-1, a chromosomal class C β-lactamase, among clinical Aeromonas dhakensis isolates: distribution and clinical significance.

    Science.gov (United States)

    Wu, Chi-Jung; Wang, Hsuan-Chen; Chen, Po-Lin; Chang, Ming-Chung; Sunny Sun, H; Chou, Pei-Hsin; Ko, Wen-Chien

    2013-11-01

    Aeromonas dhakensis, a recently described Aeromonas sp. formerly called Aeromonas aquariorum, is associated with human infections. In this study, a chromosomal gene, blaAQU-1, was identified in A. dhakensis AAK1 that constitutes a 1143-bp open reading frame and is 87% identical to the gene encoding CepH in Aeromonas hydrophila. An Escherichia coli TOP10 cell transformant harbouring blaAQU-1 was resistant to cefotaxime but not to cefepime. mRNA expression of blaAQU-1 in the cefotaxime-resistant mutant strain AAK1m was 70-fold higher than in the wild strain AAK1. In all 16 A. dhakensis isolates (the major species of 51 consecutive Aeromonas blood isolates collected from June 1999 to June 2001) as well as in A. aquariorum MDC47(T) and A. hydrophila subsp. dhakensis LMG 19562(T), but not in the reference strains or clinical isolates of other A. hydrophila subspecies, Aeromonas caviae, Aeromonas veronii or Aeromonas enteropelogenes, blaAQU-1-related genes were detected by PCR. Overall, 13 (81%) of the 16 A. dhakensis blood isolates exhibited either cefotaxime resistance or the in vitro emergence of derepressed cefotaxime-resistant mutants. In vivo selection of an A. dhakensis resistant mutant was noted in a burn patient undergoing cefotaxime monotherapy. These observations suggest that AQU-1 is a chromosomal cephalosporinase in A. dhakensis. Cefotaxime monotherapy for severe A. dhakensis infections should be used cautiously.

  8. A prospective study on Aeromonas in outpatients with diarrhea in the central region of Rio Grande do Sul State

    Directory of Open Access Journals (Sweden)

    Karoline de Campos Prediger

    2012-09-01

    Full Text Available Aeromonas spp. were identified in five (2,7% of 182 diarrheal stool cultures, A. caviae was predominant, resistant mainly to ampicillin and cephalotin. This is the first study showing the presence of Aeromonas spp. in diarrheal stools of outpatients in the central region of Rio Grande do Sul State, Brazil.

  9. Aeromonas sp.F3胶原酶性质的研究%Characteristies of collagenase from Aeromonas sp.F3

    Institute of Scientific and Technical Information of China (English)

    白杨; 钱斯日古楞; 王红英; 马蕾

    2011-01-01

    Aeromonas sp. F3 was screened from marine mud for hydrolyzing collagen. The characteristics of collagenase from Aeromonas sp. F3 were investigated via single-factor test. Thermal treatment at 50 ℃ for 40 min resulted in obvious deactivation. The optimum reaction temperature and pH was 40 ℃ and 8. 6. Collagenase activity was activated by Ca2+ at 0. 5 mmol/L. The molecular weight of the hydrolyzate was under 30 ku.%海洋污泥中筛选得到的Aeromonas sp.F3所产的胞外酶对胶原蛋白有水解作用.以海洋微生物Aeromonas sp.F3为酶源,采用单因素试验法对其所产的胶原酶性质进行了研究,包括该胶原酶的酶解条件及热稳定性,并对该胶原酶水解鱼皮的效果进行了分析.结果表明,微生物Aeromonas sp.F3源胶原酶在50℃热处理40 min之后明显失活,该胶原酶的最适反应温度为40℃,最适pH为8.6,金属离子Ca2在0.5 mmol/L时对酶有激活作用.该酶在其最适条件下,对鱼皮胶原有显著水解效能,其水解产物的分子质量在30 ku以下.

  10. Phylogenetic diversity of Aeromonas from "alheira," a traditional Portuguese meat product.

    Science.gov (United States)

    Fontes, M C; Martins, C; Martínez-Murcia, A J; Saavedra, M J

    2012-08-01

    "Alheira" is a traditional smoked meat sausage produced in the north of Portugal, representing an important economic resource for the region. This meat product has been subjected to research studies with the aim of detecting the presence of common foodborne pathogens, but, to our knowledge, isolation of emerging foodborne Aeromonas from alheira has never been previously described. Present work attempts to evaluate the Aeromonas species diversity of 84 isolates of Aeromonas spp. collected from 32 alheira samples. All presumptive Aeromonas isolates were subjected to genotyping by enterobacterial repetitive intergenic consensus-polymerase chain reaction analysis. The isolates presenting a different pattern were subjected to gyrB gene sequencing for species classification, and the species A. hydrophila, A. salmonicida, A. caviae, A. media, and A. allosaccharophila were identified. The Aeromonas species diversity found has not been previously described in any other meat product evaluated in previous studies. It is also important to highlight the presence of A. hydrophila and A. caviae because they were previously associated with illness in humans, including gastroenteritis.

  11. Molecular detection and antimicrobial resistance of Aeromonas from houseflies (Musca domestica in Iran

    Directory of Open Access Journals (Sweden)

    Davood Ommi

    2015-11-01

    Full Text Available Objective. This study aimed to report the molecular detection and antimicrobial resistance of Aeromonas among houseflies (Musca domestica in Shahrekord and Isfahan provinces of Iran. Materials and methods. Flies were caught from household kitchens, cattle farms, animal hospitals, human hospitals, slaughter house and poultry farms and put in collection separate sterile tubes. Isolation was accomplished by culture of flies in alkaline peptone water followed by identification with Aeromonas-specific Polymerase Chain Reaction (PCR. Results. Out of 600 houseflies 73 (12.2% were infected with Aeromonas spp. Significantly higher frequencies of Aeromonas were isolated in Shahrekord province (13.0%; 39/300 than in Isfahan province (11.3%; 34/300. The recovery frequencies of the organisms were significantly lower in kitchens as compared to those in cattle farms and hospital wards which were similar. Higher proportions of infected flies were obtained during summer whereas low proportions were obtained during winter. Conclusions. It is concluded that houseflies do harbor diarrheagenic pathogens, including Aeromonas especially during summer. The carried organisms are resistant to a number of antimicrobials at different levels. Thus, future plans aimed at stemming infections caused by these organisms should take flies into account. Control efforts of infections caused by this particular bacterium should therefore take into account Musca domestica.

  12. Ocorrência de bactérias do gênero Aeromonas em queijo-de-minas frescal artesanal Occurrence of the genus Aeromonas in minas frescal cheese

    Directory of Open Access Journals (Sweden)

    C.C.C. Bulhões

    2002-06-01

    Full Text Available Foram analisadas 160 amostras de queijo-de-minas frescal artesanal, adquiridas no comércio varejista dos municípios de Poços de Caldas - MG e Jaboticabal - SP, a fim de verificar a ocorrência de bactérias do gênero Aeromonas no produto. Oitenta e duas (51,2% encontravam-se contaminadas pelos microrganismos, com populações que variavam de 5,0×10³ a 4,0×10(5 UFC/grama. Foram identificadas as espécies Aeromonas hydrophila, Aeromonas caviae, Aeromonas schubertii, além de cepas consideradas atípicas. Os resultados evidenciam que bactérias do gênero Aeromonas podem ser veiculadas através do queijo tipo minas frescal artesanal e devem servir de alerta aos serviços de saúde pública.One hundred and sixty samples of homemade minas frescal cheese, obtained at the retail trade in the municipalities of Poços de Caldas-MG and Jaboticabal-SP, were analyzed for occurrence of the genus Aeromonas. Eighty two samples (51.2% were contaminated by these microorganisms with populations that ranged from 5.0 x 10³ to 4.0 x 10(5 CFU/g. The species Aeromonas hydrophila, Aeromonas caviae, Aeromonas schubertii, were identified, along with atypical strains. The results show that Aeromonas bacteria genus can be transmitted through the homemade minas frescal cheese and they should serve of alert to the public health services.

  13. A molecular study on the prevalence and virulence potential of Aeromonas spp. recovered from patients suffering from diarrhea in Israel.

    Directory of Open Access Journals (Sweden)

    Yigal Senderovich

    Full Text Available BACKGROUND: Species of the genus Aeromonas are native inhabitants of aquatic environments and have recently been considered emerging human pathogens. Although the gastrointestinal tract is by far the most common anatomic site from which aeromonads are recovered, their role as etiologic agents of bacterial diarrhea is still disputed. Aeromonas-associated diarrhea is a phenomenon occurring worldwide; however, the exact prevalence of Aeromonas infections on a global scale is unknown. METHODOLOGY/PRINCIPAL FINDINGS: The prevalence and virulence potential of Aeromonas in patients suffering from diarrhea in Israel was studied using molecular methods. 1,033 diarrheal stools were sampled between April and September 2010 and Aeromonas species were identified in 17 (∼2% patients by sequencing the rpoD gene. Aeromonas species identity and abundance was: A. caviae (65%, A. veronii (29% and Aeromonas taiwanensis (6%. This is the first clinical record of A. taiwanensis as a diarrheal causative since its recent discovery from a wound infection in a patient in Taiwan. Most of the patients (77% from which Aeromonas species were isolated were negative for any other pathogens. The patients ranged from 1 to 92 years in age. Aeromonas isolates were found to possess different virulence-associated genes: ahpB (88%, pla/lip/lipH3/apl-1 (71%, act/hlyA/aerA (35%, alt (18%, ast (6%, fla (65%, lafA (41%, TTSS ascV (12%, TTSS ascF-ascG (12%, TTSS-dependent ADP-ribosylating toxins aexU (41% and aexT (6% in various combinations. Most of the identified strains were resistant to beta-lactam antibiotics but susceptible to third-generation cephalosporin antibiotics. CONCLUSIONS: Aeromonas may be a causative agent of diarrhea in patients in Israel and therefore should be included in routine bacteriological screenings.

  14. Enterobacter asburiae and Aeromonas hydrophila: soft tissue infection requiring debridement.

    Science.gov (United States)

    Koth, Kevin; Boniface, James; Chance, Elisha A; Hanes, Marina C

    2012-06-01

    Enterobacter asburiae and Aeromonas hydrophila are gram-negative bacilli that have been isolated in soil and water. Enterobacter asburiae can cause an array of diseases, and exposure to A hydrophila can cause soft tissue infections, including necrotizing faciitis.A healthy-appearing 22-year-old man presented with an innocuous soft tissue injury to his leg due to an all-terrain vehicle crash. He received intravenous antibiotics and was discharged with prophylactic oral antibiotics. After the rapid onset of high fevers (102°F-103°F) <24 hours postinjury, he returned to the emergency department. Emergent surgical debridement was performed, and broad-spectrum intravenous antibiotics were started. Fevers persisted, and the patient underwent repeat extensive surgical debridement and antibiotic bead placement <30 hours after the initial surgical debridement and broad-spectrum antibiotics. Intraoperative cultures found E asburiae and A hydrophila in the wound. Following a long course of antibiotics and a skin graft, he fully recovered and had no functional deficits 1 year postoperatively.Extensive research revealed that these organisms are rare in soft tissue infections. E asburiae is opportunistic but has not been reported as a primary wound organism, and A hydrophila infections have been reported following motor vehicle crashes involving wound contamination. At presentation, it is challenging to determine rare organisms in a timely fashion; however, emergent extensive surgical intervention of an accelerated aberrant disease process should be considered to avoid catastrophic outcomes.

  15. Physiological control of amonabactin biosynthesis in Aeromonas hydrophila.

    Science.gov (United States)

    Barghouthi, S; Young, R; Arceneaux, J E; Byers, B R

    1989-01-01

    Amonabactin is a siderophore from Aeromonas hydrophila which is produced in two biologically active forms composed of the phenolate 2,3-dihydroxybenzoic acid (DHB), lysine, glycine, and either trytophan (amonabactin T) or phenylalanine (amonabactin P). Amonabactin biosynthetic mutants (generated by chemical mutagenesis) that either produced no amonabactin or overproduced the siderophore were isolated and identified on chrome azurol S siderophore detection agar. Amonabactin-negative mutants were of two categories. One type produced no phenolates and used exogenous DHB to synthesize amonabactin (both forms) while the other type excreted DHB but not amonabactin. This suggests an amonabactin biosynthetic pathway composed of two segments, one producing DHB and the other assembling amonabactin from DHB and the amino acids. Overproduction mutants used amonabactin poorly or not at all, indicating that they contained lesions in amonabactin utilization. Adding the analog D-tryptophan to wild-type A. hydrophila cultures reduced synthesis of both amonabactin T and amonabactin P and lengthened the lag phase in iron restricted medium. The tryptophan and phenylalanine forms of amonabactin may be synthesized by a single assembly pathway that contains a novel enzyme (sensitive to D-tryptophan) which inserts either tryptophan or phenylalanine into amonabactin.

  16. Aeromonas cavernicola sp. nov., isolated from fresh water of a brook in a cavern.

    Science.gov (United States)

    Martínez-Murcia, Antonio; Beaz-Hidalgo, Roxana; Svec, Pavel; Saavedra, Ma José; Figueras, Ma José; Sedlacek, Ivo

    2013-02-01

    Aeromonas P2973 was isolated from the water of a brook in a cavern in the Czech Republic. This isolate could not be biochemically identified at the species level, considering all updated species descriptions. Subsequent extensive phenotypic characterisation, DNA-DNA hybridisation, 16S rRNA gene sequencing and a Multi-Locus Phylogenetic Analysis (MLPA) of the concatenated sequence of 7 housekeeping genes (gyrB, rpoD, recA, dnaJ, gyrA, dnaX and atpD; 4705 bp) was employed in an attempt to ascertain the taxonomy of this isolate. Based on this polyphasic approach, we describe a novel species of the genus Aeromonas, for which the name Aeromonas cavernicola sp. nov. is proposed, with strain CCM7641(T) (DSM24474(T), CECT7862(T)) as the type strain.

  17. Molecular characterization of fluoroquinolone-resistant Aeromonas spp. isolated from imported shrimp.

    Science.gov (United States)

    Shakir, Zakiya; Khan, Saeed; Sung, Kidon; Khare, Sangeeta; Khan, Ashraf; Steele, Roger; Nawaz, Mohamed

    2012-11-01

    Sixty-three nalidixic acid-resistant Aeromonas sp. isolates were obtained from imported shrimp. Phylogenetic analysis of gyrB sequences indicated that 18 were A. enteropelogenes, 26 were A. caviae, and 19 were A. sobria. Double missense mutations in the quinolone resistance-determining region (QRDR) of gyrA at codon 83 (Ser→Val/Ile) and codon 92 (Leu→Met) coupled with a point mutation of parC at codon 80 (Ser→Ile/Phe) conferred high levels of quinolone resistance in the isolates. A majority of A. enteropelogenes and A. caviae strains harbored toxin genes, whereas only a few A. sobria strains harbored these genes. The fluoroquinolone-resistant Aeromonas spp. exhibited higher cytotoxicity than fluoroquinolone-sensitive, virulent Aeromonas spp. to rat epithelial cells.

  18. Evaluation of the MALDI-TOF MS profiling for identification of newly described Aeromonas spp.

    Science.gov (United States)

    Vávrová, Andrea; Balážová, Tereza; Sedláček, Ivo; Tvrzová, Ludmila; Šedo, Ondrej

    2015-09-01

    The genus Aeromonas comprises primarily aquatic bacteria and also serious human and animal pathogens with the occurrence in clinical material, drinking water, and food. Aeromonads are typical for their complex taxonomy and nomenclature and for limited possibilities of identification to the species level. According to studies describing the use of MALDI-TOF MS in diagnostics of aeromonads, this modern chemotaxonomical approach reveals quite high percentage of correctly identified isolates. We analyzed 64 Aeromonas reference strains from the set of 27 species. After extending the range of analyzed Aeromonas species by newly described ones, we proved that MALDI-TOF MS procedure accompanied by Biotyper tool is not a reliable diagnostic technique for aeromonads. We obtained quite high percentage of false-positive, incorrect, and uncertain results. The identification of newly described species is accompanied with misidentifications that were observed also in the case of pathogenic aeromonads.

  19. Phylogenetic diversity, antibiotic resistance and virulence traits of Aeromonas spp. from untreated waters for human consumption.

    Science.gov (United States)

    Carvalho, Maria João; Martínez-Murcia, Antonio; Esteves, Ana Cristina; Correia, António; Saavedra, Maria José

    2012-10-15

    It is well known that water constitutes an important contamination route for microorganisms. This is especially true for Aeromonas which are widespread in untreated and treated waters. In this study, Portuguese untreated waters not regularly monitored were screened for the presence and diversity of aeromonads. A total of 206 isolates were discriminated by RAPD-PCR and 80 distinct strains were identified by gyrB based phylogenetic analysis. The most frequently detected species were Aeromonas hydrophila, Aeromonas bestiarum and Aeromonas media. The antibiotic susceptibility profile of these strains was determined and showed a typical profile of the genus. Nonetheless, the percentage of resistant strains to tetracycline, chloramphenicol and/or trimethoprim/sulfamethoxazole was lower than that reported for clinical isolates and isolates recovered from aquacultures and other environments historically subjected to antibiotic contamination. This suggests that the existence of such pressures in those environments selects for resistant Aeromonas. A similar trend for integron presence was found. Genes coding for CphA and TEM, and tet(A), (E), (C) or (D) genes were found in 28%, 1%, and 10% of the strains, respectively. 10% of the strains contained an integron. Variable regions of seven class 1 integrons and one class 2 integron were characterised. Furthermore, strains displayed virulence related phenotypes such as extracellular lipolytic and proteolytic activities as well as aerolysin related genes (43% of strains). The ascV and aexT genes were found in 16% and 3% of strains respectively and, in some cases, concomitantly in the same specimen. This study shows that diverse Aeromonas spp. presenting distinct antibiotic resistance features and putative virulence traits are frequently present in waters for human and animal consumption in Portugal. Genes associated to antibiotic resistance and microbial virulence previously identified in organisms with human health significance

  20. Phenotypic and Genetic Diversity of Aeromonas Species Isolated from Fresh Water Lakes in Malaysia.

    Science.gov (United States)

    Khor, Wei Ching; Puah, Suat Moi; Tan, Jin Ai Mary Anne; Puthucheary, S D; Chua, Kek Heng

    2015-01-01

    Gram-negative bacilli of the genus Aeromonas are primarily inhabitants of the aquatic environment. Humans acquire this organism from a wide range of food and water sources as well as during aquatic recreational activities. In the present study, the diversity and distribution of Aeromonas species from freshwater lakes in Malaysia was investigated using glycerophospholipid-cholesterol acyltransferase (GCAT) and RNA polymerase sigma-factor (rpoD) genes for speciation. A total of 122 possible Aeromonas strains were isolated and confirmed to genus level using the API20E system. The clonality of the isolates was investigated using ERIC-PCR and 20 duplicate isolates were excluded from the study. The specific GCAT-PCR identified all isolates as belonging to the genus Aeromonas, in agreement with the biochemical identification. A phylogenetic tree was constructed using the rpoD gene sequence and all 102 isolates were identified as: A. veronii 43%, A. jandaei 37%, A. hydrophila 6%, A. caviae 4%, A. salmonicida 2%, A. media 2%, A. allosaccharophila 1%, A. dhakensis 1% and Aeromonas spp. 4%. Twelve virulence genes were present in the following proportions--exu 96%, ser 93%, aer 87%, fla 83%, enolase 70%, ela 62%, act 54%, aexT 33%, lip 16%, dam 16%, alt 8% and ast 4%, and at least 2 of these genes were present in all 102 strains. The ascV, aexU and hlyA genes were not detected among the isolates. A. hydrophila was the main species containing virulence genes alt and ast either present alone or in combination. It is possible that different mechanisms may be used by each genospecies to demonstrate virulence. In summary, with the use of GCAT and rpoD genes, unambiguous identification of Aeromonas species is possible and provides valuable data on the phylogenetic diversity of the organism.

  1. Phenotypic and Genetic Diversity of Aeromonas Species Isolated from Fresh Water Lakes in Malaysia.

    Directory of Open Access Journals (Sweden)

    Wei Ching Khor

    Full Text Available Gram-negative bacilli of the genus Aeromonas are primarily inhabitants of the aquatic environment. Humans acquire this organism from a wide range of food and water sources as well as during aquatic recreational activities. In the present study, the diversity and distribution of Aeromonas species from freshwater lakes in Malaysia was investigated using glycerophospholipid-cholesterol acyltransferase (GCAT and RNA polymerase sigma-factor (rpoD genes for speciation. A total of 122 possible Aeromonas strains were isolated and confirmed to genus level using the API20E system. The clonality of the isolates was investigated using ERIC-PCR and 20 duplicate isolates were excluded from the study. The specific GCAT-PCR identified all isolates as belonging to the genus Aeromonas, in agreement with the biochemical identification. A phylogenetic tree was constructed using the rpoD gene sequence and all 102 isolates were identified as: A. veronii 43%, A. jandaei 37%, A. hydrophila 6%, A. caviae 4%, A. salmonicida 2%, A. media 2%, A. allosaccharophila 1%, A. dhakensis 1% and Aeromonas spp. 4%. Twelve virulence genes were present in the following proportions--exu 96%, ser 93%, aer 87%, fla 83%, enolase 70%, ela 62%, act 54%, aexT 33%, lip 16%, dam 16%, alt 8% and ast 4%, and at least 2 of these genes were present in all 102 strains. The ascV, aexU and hlyA genes were not detected among the isolates. A. hydrophila was the main species containing virulence genes alt and ast either present alone or in combination. It is possible that different mechanisms may be used by each genospecies to demonstrate virulence. In summary, with the use of GCAT and rpoD genes, unambiguous identification of Aeromonas species is possible and provides valuable data on the phylogenetic diversity of the organism.

  2. Spontaneous aeromonas peritonitis%自发性气单胞菌腹膜炎

    Institute of Scientific and Technical Information of China (English)

    陆天雨

    2011-01-01

    自发性气单胞菌腹膜炎的发生在肝硬化腹水患者中并不罕见.本文就如何诊断及预防自发性气单胞菌腹膜炎,提高患者预后综述如下.%Spontaneous aeromonas peritonitis is a common complication in hepatocirrhosis patients with hepatic ascites.The aim of this review is to discuss how to diagnose and prevent spontaneous Aeromonas peritonitis.

  3. Identification of atypical Aeromonas salmonicida : Inter-laboratory evaluation and harmonization of methods

    DEFF Research Database (Denmark)

    Dalsgaard, Inger; Gudmundsdottir, B.K.; Helgason, S.;

    1998-01-01

    The atypical isolates of Aeromonas salmonicida are becoming increasingly important as the frequency of isolation of bacteria belonging to this group continues to rise. The primary object of this study was to compare and evaluate the results obtained in various laboratories concerning the biochemi......The atypical isolates of Aeromonas salmonicida are becoming increasingly important as the frequency of isolation of bacteria belonging to this group continues to rise. The primary object of this study was to compare and evaluate the results obtained in various laboratories concerning...

  4. Antibiotic resistance profiling and phenotyping of Aeromonas species isolated from aquatic sources

    OpenAIRE

    Olumide A. Odeyemi; Ahmad, Asmat

    2015-01-01

    This study aimed to investigate antibiotics resistance pattern and phenotyping of Aeromonas species isolated from different aquatic sources in Melaka, Malaysia. A total of 53 Aeromonas species were isolated from the following sources: sediment (n = 13), bivalve (n = 10), sea cucumber (n = 16) and sea water (n = 14) and resistance to 12 antibiotics – Tetracycline (30 μg), Kanamycin (30 μg), Oxytetracycline (30 μg), Ampicillin (10 μg), Streptomycin (10 μg), Gentamicin (10 μg), Sulphamethoxazole...

  5. Antibiotic resistance profiling and phenotyping of Aeromonas species isolated from aquatic sources

    OpenAIRE

    Olumide A. Odeyemi; Asmat Ahmad

    2017-01-01

    This study aimed to investigate antibiotics resistance pattern and phenotyping of Aeromonas species isolated from different aquatic sources in Melaka, Malaysia. A total of 53 Aeromonas species were isolated from the following sources: sediment (n = 13), bivalve (n = 10), sea cucumber (n = 16) and sea water (n = 14) and resistance to 12 antibiotics – Tetracycline (30 μg), Kanamycin (30 μg), Oxytetracycline (30 μg), Ampicillin (10 μg), Streptomycin (10 μg), Gentamicin (10 μg), Sulphamethoxazole...

  6. Levels of enzymes in leukaemic mice treated withAeromonas L-asparaginase.

    Science.gov (United States)

    Benny, P J; Muraleedhara Kurup, G; Sreejith, K

    1999-07-01

    L-asparaginase isolated in our laboratory fromAeromonas has been found to be antileukaemic. In the present study changes in the levels of serum enzymes in leukaemic mice and under treatment withAeromonas L-asparaginase has been compared. A significant increase in the levels of serum lactate dehydrogenase with tumour growth and a decrease during therapy was observed. A significant decrease in alanine transaminase activity during tumour growth and an increase during treatment was noticed. Increased levels of aspartate transaminase and alkaline phosphatase was observed during enzyme therapy. Total acid phosphatase was found to be increased during tumour growth and decreased considerably during treatment.

  7. Metabolism of proteins and glycoproteins in tumour bearing mice treated with Aeromonas L-asparaginase.

    Science.gov (United States)

    Benny, P J; Muraleedhara, K G; Sreejith, K; Jayashree, G

    1996-12-01

    L-asparaginase, isolated in our laboratory, from Aeromonas had been found to be antileukaemic. In the present study, changes in the levels of proteins and glycoproteins in leukaemic mice and under treatment with Aeromonas L-asparaginase have been compared. Levels of protein bound hexose, fucose and sialic acid which were increased during leukaemia attained normal levels when treated with L-asparaginase. The increased blood urea level declined significantly during enzyme therapy. Effects of L-asparaginase are compared with 'Leunase', a commercially available drug used in the treatment of leukaemia.

  8. Molecular detection of the Aeromonas virulence aerolysin gene in retail meats from different animal sources in Egypt.

    Science.gov (United States)

    Osman, Kamelia; Aly, Magdy; Kheader, Afaf; Mabrok, Khaled

    2012-05-01

    Meat commonly contain the same Aeromonas spp. which occur in human diarrhoeal and non-diarrhoeal faecal samples. Motile Aeromonas were isolated from 5.6% of total 302 samples. The distribution of the isolates were 5.9 and 5.2% in fresh and frozen samples, respectively. Of the 302 samples taken of the four animal meat species investigated, the genus Aeromonas were isolated in 12.3% of the fresh samples collected from buffalo meat, in 6.5% of the samples collected from sheep meat and 14.0% from the samples collected from the cattle frozen meat samples. The camel meat did not reveal any Aeromonas isolates. Aeromonas hydrophila was isolated as the most prevalent species with 6.8%, followed by Aeromonas caviae with 2.7% and Aeromonas sobria with 2.1% from the total meat samples. Aerolysin toxin gene (aerA) was detected in 3/17 isolates of A. hydrophila isolated from contaminated meat. Infection due to bacterial pathogen with such virulent factor through contact with contaminated meat while handling them, poses health hazards to humans.

  9. Properties of hemolysin and protease produced by Aeromonas trota.

    Directory of Open Access Journals (Sweden)

    Eizo Takahashi

    Full Text Available We examined the properties of exotoxins produced by Aeromonas trota (A. enteropelogenes, one of the diarrheagenic species of Aeromonadaceae. Nine of 19 A. trota isolates that grew on solid media containing erythrocytes showed hemolytic activity. However, the hemolytic activities of the culture supernatants of these hemolytic strains of A. trota were markedly lower than those of A. sobria when cultured in liquid medium, and the amount of hemolysin detected by immunoblotting using antiserum against the hemolysin produced by A. sobria was also low. A mouse intestine loop assay using living bacterial cells showed that A. trota 701 caused the significant accumulation of fluid, and antiserum against the hemolysin produced suppressed the enterotoxic action of A. trota 701. These results indicated that A. trota 701 was diarrheagenic and the hemolysin produced was the causative agent of the enterotoxic activity of A. trota. The hemolysin in A. sobria was previously shown to be secreted in a preform (inactive form and be activated when the carboxy-terminal domain was cleaved off by proteases in the culture supernatant. Since mature hemolysin was detected in the culture supernatants of A. trota, we analyzed the extracellular protease produced by A. trota. Fifteen of 19 A. trota isolates that grew on solid media containing skim milk showed proteolytic activity. We subsequently found that most A. trota isolates possessed the serine protease gene, but not the metalloprotease gene. Therefore, we determined the nucleotide sequence of the serine protease gene and its chaperone A. trota gene. The results obtained revealed that the deduced amino acid sequences of serine protease and the chaperone were homologous to those of A. sobria with identities of 83.0% and 75.8%, respectively.

  10. Immunomodulating effect of inositol hexaphosphate against Aeromonas hydrophila-endotoxin.

    Science.gov (United States)

    Abu-El-Saad, Abdel-Aziz S A

    2007-01-01

    The present study was carried out to evaluate the effect of inositol hexaphosphate (IP6) administration on endotoxemia as an example of the systemic inflammatory response. Mice were divided into three groups as follows: First group, remained as a naive group injected intraperitoneally (i.p.) with PBS (pH 7.4; 0.2 ml/mice) at intervals parallel to the treated groups. The second group was injected i.p. with the lipopolysaccharide (LPS) of Aeromonas hydrophila once a week for four weeks at a dose of LPS suspension: 20 mg/kg mice/week. The third group was injected with the same LPS dose and synergistically intubated with IP6 three times a week for four weeks at a total dose of 4 0mg/kg. At different experimental periods (1, 2, 3 and 4 weeks), six animals from each group were sacrificed under mild diethyl ether anesthesia. Blood and sera were taken for the estimation of phagocytic activity, electrophoretic pattern of proteins and immunoglobulin levels. Also, a slice of liver was homogenized to estimate the respiratory burst enzymes activities and nitric acid synthesis. Histopathological changes of hepatic tissues were investigated. In the LPS-treated group, marked increase in the phagocytic activities and nitric oxide synthesis, and a decrease in hepatocyte catalase, total peroxidase and superoxide dismutase activities were observed. The histopathological features revealed a degeneration and highly mitotic division within the hepatic nuclei in addition to some karyomegaly and nuclear pyknosis. During the treatment period, liver sections of the LPS+IP6 group showed somewhat regenerative features. Reduction in the toxicity of free radicals by IP6 was observed and the IP6 effect seemed to be responsible for the observed ameliorative influence.

  11. Occurrence, molecular characterization, and antimicrobial susceptibility of Aeromonas spp. in marine species of shrimps cultured at inland low salinity ponds.

    Science.gov (United States)

    Yano, Yutaka; Hamano, Kaoru; Tsutsui, Isao; Aue-Umneoy, Dusit; Ban, Masatoshi; Satomi, Masataka

    2015-05-01

    We aimed to document the risk of Aeromonas spp. in marine shrimp species cultured in inland low salinity ponds in Thailand. In 14 of 18 shrimp samples retrieved from inland grow-up ponds, Aeromonas spp. were detected at ranges from 4667 to 1,500,000 CFU/g body weight. The phylogenetic tree constructed with the gyrB and cpn60 concatenated sequences indicated that the 87 isolates consisted of Aeromonas veronii (70%), Aeromonas aquariorum (18%), Aeromonas caviae (7%), Aeromonas jandaei (2%), and Aeromonas schubertii (2%). The potential virulence of the isolates was examined by phenotypic and PCR assays. Hemolytic activity and the extracellular activity of lipase, DNase, and gelatinase were observed in most isolates (94-99%). PCR revealed the presence of 9 genes related to virulence in the 87 isolates: act (75%), aer (74%), alt (30%), ast (1%), ascV (34%), aexT (24%), fla (92%), ela (34%), and lip (24%). The susceptibility profiles to 14 antimicrobial agents of isolates were typical for the genus, but resistance to cefotaxime, a third-generation cephalosporin, and imipenem were found in two A. aquariorum and in three A. veronii isolates, respectively. These resistances were confirmed by determining minimum inhibitory concentrations. Our results indicate that the microbiological risk posed by Aeromonas should be considered for marine shrimp species that are cultured in low-salinity ponds. These shrimps may also be a vehicle for the transfer of different genotypes of Aeromonas and antibiotic-resistant determinants to regions worldwide through trade.

  12. Cold Shock Exoribonuclease R(VacB) is involved in Aeromonas hydrophila Virulence

    Science.gov (United States)

    In this study, we cloned and sequenced a virulence-associated gene (vacB) from a clinical isolate SSU of Aeromonas hydrophila. We identified this gene based on our recently annotated genome sequence of the environmental isolate ATCC 7966T of A. hydrophila and the vacB gene of Shi...

  13. Cold Shock Exoribonuclease R (VacB) is Involved in Aeromonas hydrophila Pathogenesis

    Science.gov (United States)

    In this study, we cloned and sequenced a virulence-associated gene (vacB) from a clinical isolate SSU of Aeromonas hydrophila. We identified this gene based on our recently annotated genome sequence of the environmental isolate ATCC 7966T of A. hydrophila and the vacB gene of Shi...

  14. Draft genome sequences of four virulent aeromonas hydrophila strains from catfish aquaculture

    Science.gov (United States)

    Since 2009, a clonal group of virulent Aeromonas hydrophila (VAh) strains has been causing severe disease in the catfish aquaculture industry in the Southeastern United States. Here, we report draft genomes of four A. hydrophila isolates from catfish aquaculture that represent this clonal group....

  15. A Mouse Model for Characterization of Gastrointestinal Colonization Rates Among Environmental Aeromonas Isolates

    Science.gov (United States)

    The colonization rates of ten different environmental isolates of Aeromonas were determined using a novel mouse-streptomycin pre-treatment method. A novel streptomycin pre-treatment prepared animals with a transient alteration in colon flora that allowed colonization by Aeromon...

  16. Immunization with recombinant aerolysin and hemolysin protected channel catfish against virulent Aeromonas hydrophila

    Science.gov (United States)

    Aeromonas hydrophila is emerging as one of the major concerns in catfish aquaculture in the Southeastern United States due to recent outbreaks of motile aeromonad septicemia (MAS) caused by virulent clonal isolates. There is no effective vaccine currently available for the prevention of MAS. In this...

  17. Virulence and antimicrobial susceptibility of clinical and environmental strains of Aeromonas spp. from northeastern Brazil.

    Science.gov (United States)

    Castelo-Branco, Débora de Souza Collares Maia; Guedes, Glaucia Morgana de Melo; Brilhante, Raimunda Sâmia Nogueira; Rocha, Marcos Fábio Gadelha; Sidrim, José Júlio Costa; Moreira, José Luciano Bezerra; Cordeiro, Rossana de Aguiar; Sales, Jamille Alencar; Riello, Giovanna Barbosa; de Alencar, Lucas Pereira; Paiva, Manoel de Araújo Neto; Vasconcelos, David Caldas; de Menezes, Isis Sousa Bezerra; de Ponte, Yago Brito; Sampaio, Célia Maria de Souza; Monteiro, André Jalles; Bandeira, Tereza de Jesus Pinheiro Gomes

    2015-08-01

    The aims of the present study were to isolate and identify clinical and environmental strains of Aeromonas spp. by means of biochemical tests and the automated method VITEK 2 and to investigate the presence of the virulence genes cytotoxic enterotoxin (act), hemolysin (asa-1), and type III secretion system (ascV), and also the in vitro antimicrobial susceptibility of the strains. From the clinical isolates, 19 Aeromonas hydrophila, 3 Aeromonas veronii bv. sobria, and 1 Aeromonas caviae were identified, while from the environmental strains, 11 A. hydrophila, 22 A. veronii bv. sobria, 1 A. veronii bv. veronii, and 1 A. caviae were recovered. The gene act was detected in 69.5% of clinical isolates, asa-1 in 8.6%, and ascV in 34.7%. In the environmental strains, the detection rates were 51.4%, 45.7%, and 54.2% for the genes act, asa-1, and ascV, respectively. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was observed in 15 and 3 clinical strains, respectively, and resistance to ceftazidime, meropenem, imipenem, ciprofloxacin, and trimethoprim-sulfamethoxazole was observed in 1 strain for each drug. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was detected in 17 and 1 environmental strain, respectively. Higher resistance percentages were observed in clinical strains, but environmental strains also showed this phenomenon and presented a higher detection rate of virulence genes. Thus, it is important to monitor the antimicrobial susceptibility and pathogenic potential of the environmental isolates.

  18. Function of a recombinant Chitinase derived from a virulent Aeromonas hydrophila isolated from diseased channel catfish

    Science.gov (United States)

    A chitinase was identified in extracellular products of a virulent Aeromonas hydrophila isolated from diseased channel catfish (Ictalurus punctatus). Bioactive recombinant chitinase (rChi-Ah) was produced in Escherichia coli. Purified rChi-Ah had optimal activity at temperature of 42°C and pH 6.5. T...

  19. Virulence diversity among bacteremic Aeromonas isolates: ex vivo, animal, and clinical evidences.

    Directory of Open Access Journals (Sweden)

    Po-Lin Chen

    Full Text Available BACKGROUND: The objective of this study was to compare virulence among different Aeromonas species causing bloodstream infections. METHODOLOGY/PRINCIPAL FINDINGS: Nine of four species of Aeromonas blood isolates, including A. dhakensis, A. hydrophila, A. veronii and A. caviae were randomly selected for analysis. The species was identified by the DNA sequence matching of rpoD. Clinically, the patients with A. dhakensis bacteremia had a higher sepsis-related mortality rate than those with other species (37.5% vs. 0%, P = 0.028. Virulence of different Aeromonas species were tested in C. elegans, mouse fibroblast C2C12 cell line and BALB/c mice models. C. elegans fed with A. dhakensis and A. caviae had the lowest and highest survival rates compared with other species, respectively (all P values <0.0001. A. dhakensis isolates also exhibited more cytotoxicity in C2C12 cell line (all P values <0.0001. Fourteen-day survival rate of mice intramuscularly inoculated with A. dhakensis was lower than that of other species (all P values <0.0001. Hemolytic activity and several virulence factor genes were rarely detected in the A. caviae isolates. CONCLUSIONS/SIGNIFICANCE: Clinical data, ex vivo experiments, and animal studies suggest there is virulence variation among clinically important Aeromonas species.

  20. Molecular characterization of Aeromonas species isolated from farmed eels (Anguilla japonica).

    Science.gov (United States)

    Yi, Seung-Won; You, Myung-Jo; Cho, Ho-Seong; Lee, Chang-Seop; Kwon, Joong-Ki; Shin, Gee-Wook

    2013-05-31

    Seventy Aeromonas strains were identified by phylogenetic analysis using housekeeping genes (gyrB and rpoD) in order to investigate etiological agents for aeromoniasis in farmed eels (Anguilla japonica). The phylogenetic analysis showed that Aeromonas aquariorum (n=22, 31.4%) was the predominant species among the investigated eel strains, followed by Aeromonas caviae (n=16, 22.9%), A. veronii (n=13, 18.6%), A. hydrophila (n=12, 17.1%), A. jandaei (n=4, 5.7%), A. media (n=2, 2.9%), and A. trota (n=1, 1.4%). The potential virulence of the present strains was estimated by performing PCR assays using the following seven virulence genes: cytotoxic enterotoxin (act), two cytotonic enterotoxins (alt and ast), glycerophospholipid:cholesterol acyltransferase (gcaT), DNase (exu), lipase (lip), and flagellin (fla). The detection rates of act, alt, ast, gcaT, exu, lip, and fla among all 70 strains were 91.4%, 55.7%, 27.1%, 97.1%, 95.7%, 100%, and 98.6%, respectively. In genotyping of enterotoxin genes, act(+)/alt(+)/ast(+), act(+)/alt(+)/ast(-), and act(+)/alt(-)/ast(-) genotypes were prevalent in A. hydrophila (8/12 strains), A. aquariorum (13/22 strains), and A. caviae (14/16 strains), respectively, suggesting a high heterogeneity among Aeromonas species. In this study, A. aquariorum, which has been an unrecorded species in Korea, can be an etiological agent for aeromoniasis of eel.

  1. Molecular characterization of a functional type VI secretion system from a clinical isolate of Aeromonas hydrophila

    Science.gov (United States)

    Our laboratory recently molecularly characterized the type II secretion system (T2SS)-associated cytotoxic enterotoxin (Act) and the T3SS-secreted AexU effector from a diarrheal isolate SSU of Aeromonas hydrophila. The role of these toxin proteins in the pathogenesis of A. hydrop...

  2. Molecular characterization of Shewanella and Aeromonas isolates associated with spoilage of Common carp (Cyprinus carpio).

    Science.gov (United States)

    Beaz-Hidalgo, Roxana; Agüeria, Daniela; Latif-Eugenín, Fadua; Yeannes, Maria I; Figueras, Maria J

    2015-01-01

    Storage in ice is a common way of preserving commercial fish species but some microorganisms can still contaminate and participate in the spoilage of the product; therefore, identification of potential harmful microbes is important. Thirteen colonies were isolated from common carp (Cyprinus carpio) that had been stored in ice, whose phenotypic identification revealed that they belonged to the genera Aeromonas (n = 5) and Shewanella (n = 8). Molecular genotyping with ERIC-PCR showed clonality only among two of the five Aeromonas isolates and for two groups (n = 3; n = 2) of the eight Shewanella isolates. Sequencing the rpoD gene showed that four Aeromonas isolates belonged to the species Aeromonas salmonicida and one to A. sobria. Of the eight Shewanella, seven isolates cluster with Shewanella putrefaciens and one with Shewanella profunda in the 16S rRNA phylogenetic tree. However, analysis of the gyrB gene showed that these eight isolates could constitute a new species closely related to S. baltica. The Shewanella and A. salmonicida isolates produce off-odours and reduce trimethylamine oxide, indicating that they might contribute to the spoilage of the fish.

  3. Draft Genome Sequence of Marine-Derived Aeromonas caviae CHZ306, a Potential Chitinase Producer Strain

    Science.gov (United States)

    Zimpel, Cristina Kraemer; Guimaraes, Ana Marcia Sa; Pessoa, Adalberto; Rivera, Irma Nelly Gutierrez

    2016-01-01

    We report here a draft genome sequence of Aeromonas caviae CHZ306, a marine-derived bacterium with the ability to hydrolyze chitin and express high levels of chitinases. The assembly resulted in 65 scaffolds with approximately 4.78 Mb. Genomic analysis revealed different genes encoding chitin-degrading enzymes that can be used for chitin derivative production. PMID:27856589

  4. Recovery of atypical Aeromonas salmonicida from ulcerated fish from the Baltic Sea

    DEFF Research Database (Denmark)

    Wiklund, T.; Tabolina, I; Bezgachina, T.V.

    1999-01-01

    Ulcerated fish of six different species were collected during the BMB/ICES Sea-going Workshop "Fish Diseases and Parasites in the Baltic Sea", 25 November to 8 December 1994, and examined for bacteriological infections. Atypical Aeromonas salmonicida strains were isolated from the majority...

  5. Humoral immune response of catfish immunized with extracellular products of Aeromonas hydrophila

    Science.gov (United States)

    Aeromonas hydrophila is emerging as one of the major concerns in catfish aquaculture in the Southeastern United States due to recent outbreaks of motile aeromonad septicemia (MAS) caused by the pathogen. Prophylactic treatment is being sought to prevent MAS. Since multiple virulence associated facto...

  6. Detection and quantification of virulent Aeromonas hydrophila in channel catfish tissues following waterborne challenge

    Science.gov (United States)

    The aim of this study was to understand the pathogenesis of motile aeromonas septicemia caused by virulent A. hydrophila (vAh) in channel catfish, Ictalurus punctatus. Adipose fin clipped catfish were challenged with vAh using waterborne challenge method and the distribution of vAh in catfish tissue...

  7. Direct evidence of recombination in the recA gene of Aeromonas bestiarum.

    Science.gov (United States)

    Sanglas, Ariadna; Albarral, Vicenta; Farfán, Maribel; Lorén, J Gaspar; Fusté, M Carmen

    2016-03-01

    Two hundred and twenty-one strains representative of all Aeromonas species were characterized using the recA gene sequence, assessing its potential as a molecular marker for the genus Aeromonas. The inter-species distance values obtained demonstrated that recA has a high discriminatory power. Phylogenetic analysis, based on full-length gene nucleotide sequences, revealed a robust topology with clearly separated clusters for each species. The maximum likelihood tree showed the Aeromonas bestiarum strains in a well-defined cluster, containing a subset of four strains of different geographical origins in a deep internal branch. Data analysis provided strong evidence of recombination at the end of the recA sequences in these four strains. Intergenomic recombination corresponding to partial regions of the two adjacent genes recA and recX (248 bp) was identified between A. bestiarum (major parent) and Aeromonas eucrenophila (minor parent). The low number of recombinant strains detected (1.8%) suggests that horizontal flow between recA sequences is relatively uncommon in this genus. Moreover, only a few nucleotide differences were detected among these fragments, indicating that recombination has occurred recently. Finally, we also determined if the recombinant fragment could have influenced the structure and basic functions of the RecA protein, comparing models reconstructed from the translated amino acid sequences of our A. bestiarum strains with known Escherichia coli RecA structures.

  8. Aeromonas rivipollensis sp. nov., a novel species isolated from aquatic samples.

    Science.gov (United States)

    Marti, Elisabet; Balcázar, José Luis

    2015-12-01

    Two gram-negative, facultatively anaerobic, motile and rod-shaped bacteria, strains P2G1(T) and P1A11, were isolated from the Ter River in Ripoll, Spain. Phylogenetic analysis based on 16S rRNA gene sequences showed that both strains are closely related to each other and that their closest relatives were Aeromonas media ATCC 33907(T) (99.4%) and Aeromonas hydrophila ATCC 7966(T) (99.3%). Multilocus sequence analysis (MLSA) based on the partial sequences of gyrA, gyrB, rpoD, recA, and dnaJ genes suggested that these two strains represent a novel species that clustered with A. media ATCC 33907(T). This was further supported by DNA-DNA hybridization analysis between P2G1(T) and A. media LMG 9073(T). Phenotypic features also allowed their differentiation from closely related species. These two strains should, therefore, be considered to represent a novel species within the genus Aeromonas, for which the name Aeromonas rivipollensis sp. nov. is proposed.

  9. Characterization of atypical Aeromonas salmonicida isolates by ribotyping and plasmid profiling

    DEFF Research Database (Denmark)

    Pedersen, Karl; Dalsgaard, Inger; Larsen, J.L.

    1996-01-01

    A total of 38 strains of atypical Aeromonas salmonicida, three oxidase-negative but otherwise typical Aer. salmonicida, three typical Aer. salmonicida, and two reference strains, isolated from several countries and fish species were examined with respect to rRNA gene restriction patterns (ribotypes...

  10. Molecular Characterization of a Functional Type VI Secretion System from a Clinical Isolate of Aeromonas hydrophilia

    Science.gov (United States)

    Our laboratory recently molecularly characterized the type II secretion system (T2SS)-associated cytotoxic enterotoxin (Act) and the T3SS-secreted AexU effector from a diarrheal isolate SSU of Aeromonas hydrophila. The role of these toxin proteins in the pathogenesis of A. hydrop...

  11. Prevalence and diversity of Aeromonas and Vibrio spp. in coastal waters of Southern Italy

    DEFF Research Database (Denmark)

    Dumontet, S.; Krovacek, K.; Svenson, S.B.

    2000-01-01

    A survey was undertaken to examine sea water and sediment for the presence of Vibrio and Aeromonas spp. along approximately 900 km of coast in Southern Italy during early and late summer. A quantitative analysis was also done to evaluate the water fecal contamination at the stations examined...

  12. Active Shiga-Like Toxin Produced by Some Aeromonas spp., Isolated in Mexico City

    Science.gov (United States)

    Palma-Martínez, Ingrid; Guerrero-Mandujano, Andrea; Ruiz-Ruiz, Manuel J.; Hernández-Cortez, Cecilia; Molina-López, José; Bocanegra-García, Virgilio; Castro-Escarpulli, Graciela

    2016-01-01

    Shiga-like toxins (Stx) represent a group of bacterial toxins involved in human and animal diseases. Stx is produced by enterohemorrhagic Escherichia coli, Shigella dysenteriae type 1, Citrobacter freundii, and Aeromonas spp.; Stx is an important cause of bloody diarrhea and hemolytic uremic syndrome (HUS). The aim of this study was to identify the stx1/stx2 genes in clinical strains and outer membrane vesicles (OMVs) of Aeromonas spp., 66 strains were isolated from children who live in Mexico City, and Stx effects were evaluated in Vero cell cultures. The capacity to express active Stx1 and Stx2 toxins was determined in Vero cell cultures and the concentration of Stx was evaluated by 50% lethal dose (LD50) assays, observing inhibition of damaged cells by specific monoclonal antibodies. The results obtained in this study support the hypothesis that the stx gene is another putative virulence factor of Aeromonas, and since this gene can be transferred horizontally through OMVs this genus should be included as a possible causal agents of gastroenteritis and it should be reported as part of standard health surveillance procedures. Furthermore, these results indicate that the Aeromonas genus might be a potential causative agent of HUS. PMID:27725813

  13. Draft Genome Sequences of Three Aeromonas hydrophila Isolates from Catfish and Tilapia

    Science.gov (United States)

    Tekedar, Hasan C.; Kumru, Salih; Kalindamar, Safak; Karsi, Attila; Waldbieser, Geoffrey C.; Sonstegard, Tad; Schroeder, Steven G.; Liles, Mark R.; Griffin, Matt J.

    2017-01-01

    ABSTRACT Aeromonas hydrophila is a Gram-negative bacterium that is particularly adapted to freshwater environments and can cause severe infections in fish and humans. Here, we report the draft genomes of three A. hydrophila catfish and tilapia isolates. PMID:28104665

  14. Antibiotic Susceptibility Profile of Aeromonas Species Isolated from Wastewater Treatment Plant

    Directory of Open Access Journals (Sweden)

    Isoken H. Igbinosa

    2012-01-01

    Full Text Available This study assessed the prevalence of antibiotic-resistant Aeromonas species isolated from Alice and Fort Beaufort wastewater treatment plant in the Eastern Cape Province of South Africa. Antibiotic susceptibility was determined using the disc diffusion method, and polymerase chain reaction (PCR assay was employed for the detection of antibiotics resistance genes. Variable susceptibilities were observed against ciprofloxacin, chloramphenicol, nalidixic acid, gentamicin, minocycline, among others. Aeromonas isolates from both locations were 100% resistant to penicillin, oxacillin, ampicillin, and vancomycin. Higher phenotypic resistance was observed in isolates from Fort Beaufort compared to isolates from Alice. Class A pse1 β-lactamase was detected in 20.8% of the isolates with a lower detection rate of 8.3% for blaTEM gene. Class 1 integron was present in 20.8% of Aeromonas isolates while class 2 integron and TetC gene were not detected in any isolate. The antibiotic resistance phenotypes observed in the isolates and the presence of β-lactamases genes detected in some isolates are of clinical and public health concern as this has consequences for antimicrobial chemotherapy of infections associated with Aeromonas species. This study further supports wastewater as potential reservoirs of antibiotic resistance determinants in the environment.

  15. Diversity and antibiotic resistance of Aeromonas spp. in drinking and waste water treatment plants.

    Science.gov (United States)

    Figueira, Vânia; Vaz-Moreira, Ivone; Silva, Márcia; Manaia, Célia M

    2011-11-01

    The taxonomic diversity and antibiotic resistance phenotypes of aeromonads were examined in samples from drinking and waste water treatment plants (surface, ground and disinfected water in a drinking water treatment plant, and raw and treated waste water) and tap water. Bacteria identification and intra-species variation were determined based on the analysis of the 16S rRNA, gyrB and cpn60 gene sequences. Resistance phenotypes were determined using the disc diffusion method. Aeromonas veronii prevailed in raw surface water, Aeromonas hydrophyla in ozonated water, and Aeromonas media and Aeromonas puntacta in waste water. No aeromonads were detected in ground water, after the chlorination tank or in tap water. Resistance to ceftazidime or meropenem was detected in isolates from the drinking water treatment plant and waste water isolates were intrinsically resistant to nalidixic acid. Most of the times, quinolone resistance was associated with the gyrA mutation in serine 83. The gene qnrS, but not the genes qnrA, B, C, D or qepA, was detected in both surface and waste water isolates. The gene aac(6')-ib-cr was detected in different waste water strains isolated in the presence of ciprofloxacin. Both quinolone resistance genes were detected only in the species A. media. This is the first study tracking antimicrobial resistance in aeromonads in drinking, tap and waste water and the importance of these bacteria as vectors of resistance in aquatic environments is discussed.

  16. Lippia alba essential oil promotes survival of silver catfish (Rhamdia quelen) infected with Aeromonas sp.

    Science.gov (United States)

    Sutili, Fernando J; Cunha, Mauro A; Ziech, Rosangela E; Krewer, Carina C; Zeppenfeld, Carla C; Heldwein, Clarissa G; Gressler, Leticia T; Heinzmann, Berta M; Vargas, Agueda C; Baldisserotto, Bernardo

    2015-03-01

    In vitro and in vivo activity of the Lippia alba essential oil (EO) against Aeromonas sp. was evaluated. In the in vitro assay the minimum inhibitory concentration (MIC) and a minimum bactericidal concentration (MBC) of EO for Aeromonas cells were determined using the microdilution method. Twenty five strains of Aeromonas sp. isolated from infected fish obtained from local fish farms were used. MIC and MBC values were 2862 and 5998 µg mL-1 for L. alba EO and 0.5 and 1.2 µg mL-1 for gentamicin, respectively. In the in vivo assay silver catfish juveniles (Rhamdia quelen) (7.50 ± 1.85 g and 10.0 ± 1.0 cm) with typical injuries associated to Aeromonas infection were divided into four treatments (in triplicate n=10): untreated fish (negative control), 10 mg L-1 of gentamicin, and 20 or 50 µL L-1 of EO. Fish were maintained in aerated 20 L plastic boxes. After 10 days survival of silver catfish infected with Aermonas sp. and treated with essential oil (50 µL L-1) was greater than 90%.

  17. Clinical manifestations of bacteremia caused by Aeromonas species in southern Taiwan.

    Directory of Open Access Journals (Sweden)

    Hung-Jen Tang

    Full Text Available This study is conducted to investigate the clinical characteristics of patients with bacteremia caused by Aeromonas species.Patients with bacteremia caused by Aeromonas species during the period 2009 to 2013 were identified from a computerized database of a regional hospital in southern Taiwan. The medical records of these patients were retrospectively reviewed.A total of 91 patients with bacteremia due to Aeromonas species were identified. In addition to 16 (17.6% primary bacteremia, the most common source of secondary infection is peritonitis (n = 27, 29.7%, followed by biliary tract infection (n = 18, 19.8%, and SSTI (n = 12, 13.2%, pneumonia (n = 9, 9.9%, catheter-related bloodstream infection (n =  5, 5.5%, and genitourinary tract infection (n = 4, 4.4%. A. hydrophila (n = 35, 38.5% was the most common pathogen, followed by A. veronii biovar sobria (n = 31, 34.1%, A. caviae (n = 14, 15.4%, and A. veronii biovar veronii (n = 9, 9.9%. Forty-three (47.3% patients were classified as healthcare-associated infections (HCAI causes by Aeromonas species, and patients with HCAI were more likely to have cancer, and receive immunosuppressant than patients with community-acquired bacteremia. The overall outcomes, including rate of ICU admission, acute respiratory failure, and mortality were 33.3%, 28.6%, and 23.1%, respectively. Multivariate analysis showed that the in-hospital day mortality was significantly associated only with underlying cancer (P <.001, and initial shock (P <.001.Aeromonas species should be considered one of the causative pathogens of healthcare-associated bacteremia, especially in immunocompromised patients. In addition, it can be associated with high fatality. Cancer and initial shock were the poor prognostic factors.

  18. Envolvimento de Aeromonas em surto de doença diarréica aguda em São Bento do Una, Pernambuco Aeromonas associated with an acute diarrhea outbreak in São Bento do Una, Pernambuco

    Directory of Open Access Journals (Sweden)

    Ernesto Hofer

    2006-04-01

    Full Text Available No primeiro semestre de 2004, ocorreu um surto de diarréia em São Bento do Una, Pernambuco, registrando-se 2.170 casos. Nas 582 coproculturas realizadas, 145 (25% revelaram um enteropatógeno bacteriano, destacando 114 casos (19,5% com a participação de Aeromonas, representadas por Aeromonas caviae (57/9,8%, Aeromonas veronii biovar sobria (23/3,9%, Aeromonas veronii biovar veronii (15/2,6% e outras espécies (19/3,2%. Nos 31 episódios restantes (5,3%, foram detectados: V. cholerae O1 Ogawa toxigênico (18/3,1%, Salmonella spp (8/1,4%, Shigella spp (3/0,5% e Vibrio cholerae não O1/não O139 (2/0,3%.An acute diarrhea outbreak, with 2170 cases, was described during January to July, 2004, in São Bento do Una, Pernambuco. 582 stools were examined and an enteric pathogen was recovered in 25% (145 patients. Aeromonas species were the most frequent (114-19.5% and the main isolates were Aeromonas caviae (57-9.8%, Aeromonas veronii biovar sobria (23-3.9%, Aeromonas veronii biovar veronii (15-2.6% and other species (19-3.2%. The other isolated enteropathogens were Vibrio cholerae O1-Ogawa toxigenic (18-3.1%, Salmonella spp (8-1.4%, Shigella spp (3-0.5% and Vibrio cholerae non-O1/non-O139 (2-0.3%.

  19. The Animal Model Determines the Results of Aeromonas Virulence Factors

    Science.gov (United States)

    Romero, Alejandro; Saraceni, Paolo R.; Merino, Susana; Figueras, Antonio; Tomás, Juan M.; Novoa, Beatriz

    2016-01-01

    The selection of an experimental animal model is of great importance in the study of bacterial virulence factors. Here, a bath infection of zebrafish larvae is proposed as an alternative model to study the virulence factors of Aeromonas hydrophila. Intraperitoneal infections in mice and trout were compared with bath infections in zebrafish larvae using specific mutants. The great advantage of this model is that bath immersion mimics the natural route of infection, and injury to the tail also provides a natural portal of entry for the bacteria. The implication of T3SS in the virulence of A. hydrophila was analyzed using the AH-1::aopB mutant. This mutant was less virulent than the wild-type strain when inoculated into zebrafish larvae, as described in other vertebrates. However, the zebrafish model exhibited slight differences in mortality kinetics only observed using invertebrate models. Infections using the mutant AH-1ΔvapA lacking the gene coding for the surface S-layer suggested that this protein was not totally necessary to the bacteria once it was inside the host, but it contributed to the inflammatory response. Only when healthy zebrafish larvae were infected did the mutant produce less mortality than the wild-type. Variations between models were evidenced using the AH-1ΔrmlB, which lacks the O-antigen lipopolysaccharide (LPS), and the AH-1ΔwahD, which lacks the O-antigen LPS and part of the LPS outer-core. Both mutants showed decreased mortality in all of the animal models, but the differences between them were only observed in injured zebrafish larvae, suggesting that residues from the LPS outer core must be important for virulence. The greatest differences were observed using the AH-1ΔFlaB-J (lacking polar flagella and unable to swim) and the AH-1::motX (non-motile but producing flagella). They were as pathogenic as the wild-type strain when injected into mice and trout, but no mortalities were registered in zebrafish larvae. This study demonstrates

  20. Population dynamics and antimicrobial susceptibility of Aeromonas spp. along a salinity gradient in an urban estuary in Northeastern Brazil.

    Science.gov (United States)

    Silva, Camila Magalhães; Evangelista-Barreto, Norma Suely; Vieira, Regine Helena Silva Dos Fernandes; Mendonça, Kamila Vieira; de Sousa, Oscarina Viana

    2014-12-15

    The main objective of this study was to quantify population and identify culturable species of Aeromonas in sediment and surface water collected along a salinity gradient in an urban estuary in Northeastern Brazil. Thirty sediment samples and 30 water samples were collected from 3 sampling locations (A, B and C) between October 2007 and April 2008. The Aeromonas count was 10-7050CFU/mL (A), 25-38,500CFU/mL (B) andAeromonas caviae, A. sobria, A. trota, A. salmonicida and A. allosaccharophila) were identified among 41 isolates. All strains were sensitive to chloramphenicol and ceftriaxone, whereas 33 (80, 4%) strains were resistant to at least 2 of the 9 antibiotics tested. Resistance to erythromycin was mostly plasmidial. In conclusion, due to pollution, the Cocó River is contaminated by pathogenic strains of Aeromonas spp. with a high incidence of antibacterial resistance, posing a serious risk to human health.

  1. Survival and recovery of Aeromonas hydrophila in water: development of methodology for testing bottled water in Canada.

    Science.gov (United States)

    Warburton, D W; McCormick, J K; Bowen, B

    1994-02-01

    Proposed changes to the Regulations for bottled water in the Food and Drugs Act of Canada include criteria for Aeromonas hydrophila (0 colony-forming units/100 mL water). The development of the methodology used to support these proposed Regulations and the survival of A. hydrophila in inoculated water are described. The methodology used in the isolation of A. hydrophila includes the use of hydrophobic grid membrane filters (HGMF), a resuscitation step on tryptic soy agar, and selective plating on membrane-Aeromonas-trehalose agar and Aeromonas medium. Aeromonas hydrophila proliferated and survived in inoculated water for up to 60 days or longer depending on the other contaminating bacteria. The presence of Pseudomonas aeruginosa enhanced the survival of A. hydrophila and enabled this bacteria to survive for more than 60 days.

  2. Determination of the Viability of Aeromonas hydrophila in Different Types of Water by Flow Cytometry, and Comparison with Classical Methods

    OpenAIRE

    Pianetti, Anna; Falcioni, Tania; Bruscolini, Francesca; Sabatini, Luigia; Sisti, Elivio; Papa, Stefano

    2005-01-01

    The presence of Aeromonas spp. in water can represent a risk for human health. Therefore, it is important to know the physiological status of these bacteria and their survival in the environment. We studied the behavior of a strain of Aeromonas hydrophila in river water, spring water, brackish water, mineral water, and chlorinated drinking water, which had different physical and chemical characteristics. The bacterial content was evaluated by spectrophotometric and plate count techniques. Flo...

  3. Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii

    OpenAIRE

    Aurélie Tasiemski; François Massol; Virginie Cuvillier-Hot; Céline Boidin-Wichlacz; Emmanuel Roger; Franck Rodet; Isabelle Fournier; Frédéric Thomas; Michel Salzet

    2015-01-01

    International audience; The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, a versatile bacterium which can also display free-living waterborne and fish-or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in the dynamics of interaction between the leech and its gut symbiont Aeromonas. By combining biochemical and molecular approaches, we isolated and identified for the first time the antimicrobial peptides (AMPs) produced b...

  4. A rapid MALDI-TOF MS identification database at genospecies level for clinical and environmental Aeromonas strains.

    Directory of Open Access Journals (Sweden)

    Cinzia Benagli

    Full Text Available The genus Aeromonas has undergone a number of taxonomic and nomenclature revisions over the past 20 years, and new (subspecies and biogroups are continuously described. Standard identification methods such as biochemical characterization have deficiencies and do not allow clarification of the taxonomic position. This report describes the development of a matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF MS identification database for a rapid identification of clinical and environmental Aeromonas isolates.

  5. Phenotypical characteristics, genetic identification, and antimicrobial sensitivity of Aeromonas species isolated from farmed rainbow trout (Onchorynchus mykiss) in Mexico.

    Science.gov (United States)

    Vega-Sánchez, Vicente; Acosta-Dibarrat, Jorge; Vega-Castillo, Fernando; Castro-Escarpulli, Graciela; Aguilera-Arreola, Ma Guadalupe; Soriano-Vargas, Edgardo

    2014-02-01

    In the present study, Aeromonas isolates from diseased and healthy farmed rainbow trout (Oncorhynchus mykiss) in Mexico, were characterized phenotypically and identified to species level by using 16S rDNA RFLP-PCR. A total of 50 isolates were included in the study and 10 Aeromonas species identified. The species A. veronii biovar sobria (22%), A. hydrophila (20%) and A. bestiarum (20%) were the most predominant. All isolates (100%) were resistant to cephalothin.

  6. Incidence of Aeromonas spp. infection in fish and chicken meat and its related public health hazards: A review

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Praveen

    2016-01-01

    Full Text Available Aeromonas is recognized to cause a variety of diseases in man. In humans, they are associated with intestinal and extraintestinal infections. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors such as enterotoxins, hemolysins or cytotoxins, and antibiotic resistance against different antibiotics. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. Comprehensive enteric disease surveillance strategies, prevention and education are essential for meeting the challenges in the years ahead. It is important for us to promote the value of enteric cultures when patients have a gastrointestinal illness or bloody diarrhea or when multiple cases of enteric disease occur after a common exposure. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors, such as enterotoxins, hemolysins or cytotoxins. It has been established that aerolysin is a virulence factor contributing to the pathogenesis of Aeromonas hydrophila infection. Fish and chicken play an important role in the transmission of this pathogen to humans. In the present study, the high prevalence of toxin-producing strains was found among the Aeromonas isolates. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. The present review was constructed with a view to highlight the zoonotic importance of Aeromonas pathogen in fish and chicken meat.

  7. Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii.

    Science.gov (United States)

    Tasiemski, Aurélie; Massol, François; Cuvillier-Hot, Virginie; Boidin-Wichlacz, Céline; Roger, Emmanuel; Rodet, Franck; Fournier, Isabelle; Thomas, Frédéric; Salzet, Michel

    2015-12-04

    The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, a versatile bacterium which can also display free-living waterborne and fish- or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in the dynamics of interaction between the leech and its gut symbiont Aeromonas. By combining biochemical and molecular approaches, we isolated and identified for the first time the antimicrobial peptides (AMPs) produced by the leech digestive tract and by its symbiont Aeromonas. Immunohistochemistry data and PCR analyses evidenced that leech AMP genes are induced in the gut epithelial cells when Aeromonas load is low (starved animals), while repressed when Aeromonas abundance is the highest (post blood feeding). The asynchronous production of AMPs by both partners suggests that these antibiotic substances (i) provide them with reciprocal protection against invasive bacteria and (ii) contribute to the unusual simplicity of the gut microflora of the leech. This immune benefit substantially reinforces the evidence of an evolutionarily stable association between H. verbana and A. veronii. Altogether these data may provide insights into the processes making the association with an Aeromonas species in the digestive tract either deleterious or beneficial.

  8. AEROMONAS SPP BACTEREMIA OF RAINBOW TROUT FRY (ONCORHYNCHUS MYKISS: BIOCHEMICAL CHARACTERIZATION OF THE CAUSATIVE ORGANISM AND ANTIMICROBIAL SUSCEPTIBILITY

    Directory of Open Access Journals (Sweden)

    Damir Kapetanović

    2004-09-01

    Full Text Available Aeromonas hydrophila and other members of Aeromonas genus are ubiquitus in aquatic environment and make part of normal bacterial flora of rainbow trout. Aeromonas spp. infections are worldwide registered. Here we present our experience and knowledge on Aeromonas bacteremia, which causes mortality of rainbow trout fry. Rainbow trout fry, 7 month old, started to die in November 2003. Fish samples (17 samples of dead and moribund fish were delivered to the Laboratory for aquaculture. With Api 20 NE tests Aeromonas hydrophila / caviae type I was identified with an average probability of 99.9 % (one test against, as well as Aeromonas hydrophila / caviae type II with an average probability of 99.5 % (one test against from liver, spleen, kidney, intestines and damaged eye. All of isolated and identified samples were tested for antibiotic susceptibility by disc diffusion method. The test showed that specimens were most sensitive on flumequin, and relatively less sensitive on chloramphenicol and enrofloxacin. Therapy was successfully applied with Flubactin®.

  9. Diversidad intraespecífica y factores de virulencia en el “complejo de especies de Aeromonas hydrophila” (A. Hydrophila, A. Salmonicida, A. Bestiarum).

    OpenAIRE

    2013-01-01

    [spa] El género Aeromonas está constituido actualmente por 26 especies reconocidas, algunas de las cuales incluyen varias subespecies. Son habitantes ubicuos del agua dulce, pero también de aguas cloradas, salobres y marinas. Se han obtenido cepas de Aeromonas de una amplia variedad de alimentos, y se han aislado de muestras clínicas. Algunas especies de Aeromonas son causantes de infecciones intestinales y extraintestinales aunque los mecanismos por los que causan diarreas bacterianas no ...

  10. [Detection of the first QnrS gene positivity in aquatic Aeromonas spp. isolates in Turkey].

    Science.gov (United States)

    Onuk, Ertan Emek; Tanrıverdi Çaycı, Yeliz; Çoban, Ahmet Yılmaz; Çiftci, Alper; Balta, Fikri; Didinen, Behire Işıl; Pekmezci, Gökmen Zafer; Altun, Soner; Söğüt Ünlü, Mehtap; Deveci, Aydın

    2015-01-01

    Aeromonas spp. are oxidase positive, gram-negative, facultative anaerobic bacilli that are widely distributed in aquatic environments. A.hydrophila, A.sobria and A.bestiarum may cause severe infections in both human and cold-blooded animals. Environmental persistance of quinolones that are widely used in both human and veterinary medicine plays an important role in the selection of resistant mutants. Plasmid-mediated resistance is one of the main mechanisms involved in quinolone resistance, and qnr, qepA, aac(6')-Ib-cr, oqxAB genes are identified as resistance determinants. Determination of various types of qnr gene in different bacteria mainly in Enterobacteriaceae, suggests that they are widely distributed in nature. Recently, plasmid-mediated quinolone resistance was defined among Aeromonas species isolated from water. The aim of this study was to investigate the presence of qnr genes among aquatic Aeromonas spp. in Turkey. A total of 45 Aeromonas strains isolated from water and fishes collected from three different geographical regions (Aegean, Mediterranean and Blacksea) in Turkey, were included in the study. The isolates were identified at species level by the use of 16S rDNA-RFLP (Restriction fragment length polymorphism) analysis and multiplex polymerase chain reaction (M-PCR). Among the isolates, 20 were identified as A.sobria, 10 as A.hydrophila, nine as A.salmonicida, four as A.bestiarum and two as A.veronii. The plasmid-mediated quinolone resistance determinants, qnrA, qnrB, qnrC and qnrS genes, were investigated by M-PCR, and sequence analysis was performed for nine qnr-positive isolates. According to the sequence analysis of the genes, qnr genes were characterized in six A.sobria, in two A.bestiarum and in one A.hydrophila isolate (9/45; 20%). When the sequence was compared with GenBank database, this gene was found as qnrS2. All qnrS-positive Aeromonas spp. isolates were ciprofloxacin-susceptible, while five of them were resistant to nalidixic acid

  11. 我国嗜水气单胞菌感染研究概况%Research Survey on Infection of Aeromonas hydrophila in China

    Institute of Scientific and Technical Information of China (English)

    陈翠珍

    2012-01-01

    主要从嗜水气单胞菌感染的发现、人的嗜水气单胞菌感染、动物的嗜水气单胞菌感染、诊断要点及防控等方面对我国嗜水气单胞菌感染进行了综述。%In this report, infection of Aeromonas hydrophila overview in China was reviewed from several as- pects including the occurrence of Aeromonas hydrophila infection ,Aeromonas hydrophila infection in human be- ing and animal, diagnosis, as well as the control strategies of Aeromonas hydrophila infection.

  12. EVALUATING VIRULENCE OF WATERBORNE AND CLINCIAL AEROMONAS ISOLATES USING GENE EXPRESSION AND MORTALITY IN NEONATAL MICE FOLLOWED BY ASSESSING CELL CULTURE'S ABILITY TO PREDICT VIRULENCE BASED ON TRANSCRIPTIONAL RESPONSE

    Science.gov (United States)

    The virulence of multiple Aeromonas spp. were assessed using two models, a neonatal mouse assay and a mouse intestinal cell culture. Transcriptional responses to both infection models were assessed using microarrays. After artificial infection with a variety of Aeromonas spp., ...

  13. [Role of Aeromonas in the monitoring of a hydroecosystem in the Volga-Caspian area].

    Science.gov (United States)

    Obukhova, O V; Lartseva, L V; Lisitskaia, I A

    2011-01-01

    The paper gives data obtained over many years on the quantity of bacteria of the genus Aeromonas in the hydroecosystems of the delta of the Volga and Caspian Sea and in commercial fishes (sturgeon (Acipenseridae), pike perch (Stizostedion), carp (Cyprinus carpio), silurus (Silurus glanis), etc.). It provides a detailed analysis of their seasonal trends and spatial distribution, markers of their pathogenicity, and antibiotic resistance. The findings suggest that Aeromonas is a causative agent of sapronoses and meets the criteria for natural focal infections. They show a wide range of tolerance to the abiotic factors of hydroecosystems, as well as mixotrophy and autrophic nutrition in the environment and they are of great sanitary and hygienic importance.

  14. Pathogenicity of Aeromonas hydrophila, Klebsiella pneumoniae, and Proteus mirabilis to brown tree frogs (Litoria ewingii).

    Science.gov (United States)

    Schadich, Ermin; Cole, Anthony L J

    2010-04-01

    Bacterial dermatosepticemia, a systemic infectious bacterial disease of frogs, can be caused by several opportunistic gram-negative bacterial species including Aeromonas hydrophila, Chryseobacterium indologenes, Chryseobacterium meningosepticum, Citrobacter freundii, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, and Serratia liquifaciens. Here we determined the pathogenicity of 3 bacterial species (Aeromonas hydrophila, Klebsiella pneumoniae, and Proteus mirabilis) associated with an outbreak of fatal dermatosepticemia in New Zealand Litoria ewingii frogs. A bath challenge method was used to expose test frogs to individual bacterial species (2 x 10(7) cfu/mL in pond water); control frogs were exposed to uninfected pond water. None of the control frogs or those exposed to A. hydrophila or P. mirabilis showed any morbidity or mortality. Morbidity and mortality was 40% among frogs exposed to K. pneumonia, and the organism was reisolated from the hearts, spleens, and livers of affected animals.

  15. Lipid metabolism in tumour bearing mice treated withAeromonas L-asparaginase.

    Science.gov (United States)

    Benny, P J; Kurup, G M; Sreejith, K

    1997-07-01

    The anticancerous drug isolated in our laboratory from estuarineAeromonas was characterised and is found to be an enzyme, L-asparaginase. The antileukaemic effect of this drug was studied in mice by inducing leukaemia with Ehrlich ascites cell lines. It was compared with commercially available drug, Leunase, isolated fromE. coli. The lipid profiles in mice during leukaemia and under treatment was studied. The decreased levels of cholesterol and increased levels of triglycerides and phospholipids in serum, liver and kidney were observed in tumour bearing mice. Significant changes in the above values were observed with enzyme therapy. It could bring some of the values to near normal level. L-asparaginase fromAeromonas was found to be more effective.

  16. Experimental challenge studies in Vietnamese catfish, Pangasianodon hypophthalmus (Sauvage), exposed to Edwardsiella ictaluri and Aeromonas hydrophila.

    Science.gov (United States)

    Crumlish, M; Thanh, P C; Koesling, J; Tung, V T; Gravningen, K

    2010-09-01

    The two main diseases in the pangasius catfish industry are bacillary necrosis of Pangasianodon (BNP) and motile aeromonas septicaemia (MAS), where the aetiological agents have been identified as Edwardsiella ictaluri and Aeromonas hydrophila, respectively. In this study, apparently healthy Pangasianodon hypophthalmus were exposed to E. ictaluri, A. hydrophila or both bacterial species by intraperitoneal injection or immersion. There were 20 fish per treatment group, and the bacterial isolates used for the study were recovered from natural infections of BNP or MAS in farmed Vietnamese P. hypophthalmus. The results of the experimental infections mimicked the natural disease outbreaks reported from these pathogens in P. hypophthalmus. Furthermore, it was clearly demonstrated that E. ictaluri was only recovered from the fish exposed to the bacterium and not recovered from the animals receiving A. hydrophila.

  17. The Social Life of Aeromonas through Biofilm and Quorum Sensing Systems

    Science.gov (United States)

    Talagrand-Reboul, Emilie; Jumas-Bilak, Estelle; Lamy, Brigitte

    2017-01-01

    Bacteria of the genus Aeromonas display multicellular behaviors herein referred to as “social life”. Since the 1990s, interest has grown in cell-to-cell communication through quorum sensing signals and biofilm formation. As they are interconnected, these two self-organizing systems deserve to be considered together for a fresh perspective on the natural history and lifestyles of aeromonads. In this review, we focus on the multicellular behaviors of Aeromonas, i.e., its social life. First, we review and discuss the available knowledge at the molecular and cellular levels for biofilm and quorum sensing. We then discuss the complex, subtle, and nested interconnections between the two systems. Finally, we focus on the aeromonad multicellular coordinated behaviors involved in heterotrophy and virulence that represent technological opportunities and applied research challenges. PMID:28163702

  18. Resistensi Bakteri Aeromonas sp. Isolat Ikan Piranha (Pygosentrus nattereri Bali Safari And Marine Park terhadap Antibiotik

    Directory of Open Access Journals (Sweden)

    Ni Made Herawati

    2013-11-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Piranha (Pygosentrus nattereri is a fish that has been conserved at Conservation Center of Bali Safari and Marine Park. In May 2012 there was a case that twelve Piranhas suffered from illness and two of them died without any specific clinical signs. The dead Piranhas were necropsied and the tissues or parts of organs were collected for microbial examination interests. Spesies specific bacterial examination was also included using Microgen GNA TM + B-ID system test The bacterial examination found that the fishes were infected by Aeromonas hydropila and Aeromonas veronii. Further examination about antibiotic resistance tests showed that those Aeromonas spp were resistant to chloramphenicol and a combination of trimethoprim and sulphamethoxazole. It can be suggested that, next, the usage of other antibiotics is strongly recommended for the case of Piranha infected by Aeromonas spp at Bali Safari and Marine Park. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; text-align:justify; line-height:150%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

  19. Natural transformation as a mechanism of horizontal gene transfer among environmental Aeromonas species.

    Science.gov (United States)

    Huddleston, Jennifer R; Brokaw, Joshua M; Zak, John C; Jeter, Randall M

    2013-06-01

    Aeromonas species are common inhabitants of aquatic environments and relevant as human pathogens. Their potential as pathogens may be related in part to lateral transfer of genes associated with toxin production, biofilm formation, antibiotic resistance, and other virulence determinants. Natural transformation has not been characterized in aeromonads. DNA from wild-type, prototrophic strains that had been isolated from environmental sources was used as donor DNA in transformation assays with auxotrophs as the recipients. Competence was induced in 20% nutrient broth during the stationary phase of growth. Optimal transformation assay conditions for one chosen isolate were in Tris buffer with magnesium or calcium, pH 5-8, and a saturating concentration of 0.5 μg of DNA per assay (3.3 ng of DNA μl⁻¹) at 30°C. Sodium was also required and could not be replaced with ammonium, potassium, or lithium. The maximal transformation frequency observed was 1.95 × 10⁻³ transformants (recipient cell)⁻¹. A survey of environmental Aeromonas auxotrophic recipients (n=37), assayed with donor DNA from other wild-type environmental aeromonads under optimal assay conditions, demonstrated that 73% were able to act as recipients, and 100% were able to act as donors to at least some other aeromonads. Three different transformation groups were identified based on each isolates' ability to transform other strains with its DNA. The transformation groups roughly corresponded to phylogenetic groups. These results demonstrate that natural transformation is a general property of Aeromonas environmental isolates with implications for the genetic structures of coincident Aeromonas populations.

  20. Rapid biochemical screening for Salmonella, Shigella, Yersinia, and Aeromonas isolates from stool specimens.

    OpenAIRE

    De Ryck, R; Struelens, M. J.; Serruys, E

    1994-01-01

    Four screens for the rapid (4 to 6 h) biochemical detection of pathogens from enteric isolation media are described. The Salmonella screen consisted of Kligler iron agar (KIA), motility-indole-urea-tryptophan-deamination semisolid medium (MIU-TDA), and the o-nitrophenyl-beta-D-galactopyranoside (ONPG) test; the Shigella screen consisted of KIA, MIU-TDA, the ONPG test, and the lysine decarboxylation-indole test; the Yersinia screen consisted of a rhamnose broth; the Aeromonas screen consisted ...

  1. ANTIBIOTICS RESISTANCE AND PUTATIVE VIRULENCE FACTORS OF AEROMONAS HYDROPHILA ISOLATED FROM ESTUARY

    OpenAIRE

    Olumide Adedokun Odeyemi; Ahmad Asmat; Gires Usup

    2012-01-01

    This study aim to investigate antibiotics resistance profile and putative virulence factors of Aeromonas hydrophila isolated from estuary. Bacteria used for this study were isolated from water and sediment samples obtained from Sungai Melayu, Johor, Malaysia. Serially diluted 100 µL water and 1g sediment were inoculated on modified Rimler - Shott (mRS) agar. Colonies with distinct cultural characteristics were picked for further studies. Isolates were tested for biofilm productions, protease ...

  2. Necrotizing Fasciitis Caused by Inconspicuous Infection of Aeromonas hydrophila in an Immunocompromised Host

    Directory of Open Access Journals (Sweden)

    Kuo-Chun Liao

    2010-09-01

    Full Text Available We present a case of serious necrotizing fasciitis due to Aeromonas hydrophila without a suggestive history of routes of pathogen invasion in a 60-year-old male. Despite prompt broad-spectrum antibiotic and extensive surgical therapies, the patient died within 72 hours following initial presentation. Our experience suggests clinicians be highly alert to the disease when an immunocompromised patient featured fulminant soft-tissue infection in the endemic area.

  3. Influence of food system conditions on N-acyl-L-homoserine lactones production by Aeromonas spp.

    Science.gov (United States)

    Medina-Martínez, M S; Uyttendaele, M; Demolder, V; Debevere, J

    2006-12-01

    Eleven of 13 Aeromonas strains were shown to produce AHLs. Results of TLC showed that N-butanoyl-L-homoserine lactone (C4-HSL) was the main AHL produced in LB medium at 30 degrees C. The influence of different carbon sources, temperature, pH values and salt concentrations on AHL production was determined in eight A. hydrophila and one A. caviae strain. Additionally a quantitative study of C4-HSL production by A. hydrophila strain 519 under different conditions was performed. Positive results were found in the AHL induction assay for some Aeromonas strains in cultures in LB agar incubated at 12 degrees C after 72-96 h. The induction of the sensor strains by Aeromonas spp. occurred in LB medium supplemented with all carbon sources in a concentration of 0.5%. The production of C4-HSL by A. hydrophila 519 was found until 3.5% (w/v) of NaCl. For pHs close to the neutrality the C4-HSL production by A. hydrophila was evident after 24-48 h of incubation. A. hydrophila 519 produced C4-HSL under anaerobic conditions. Also, the AHL production by Aeromonas strains was studied in simulate agar of shrimp, fish and some vegetables. The production of AHLs was evident by almost all the test strains in shrimp simulated agar. In fish agar only for one of three fish species tested, positive results were found. Induction assay in vegetables simulated agar showed principally negative results, probably because of the presence of inhibitory compounds in these vegetables.

  4. PROBIOTIK Bacillus firmus UNTUK PENGENDALIAN PENYAKIT Aeromonas hydrophila PADA BUDIDAYA IKAN LELE DUMBO, Clarias gariepinus

    OpenAIRE

    Angela Mariana Lusiastuti; Tuti Sumiati; Wartono Hadie

    2013-01-01

    Penelitian ini bertujuan untuk mengetahui efektivitas pemberian bakteri probiotik Bacillus firmus terhadap ketahanan benih ikan lele dumbo (Clarias gariepinus) yang diinfeksi Aeromonas hydrophila. Probiotik diberikan melalui media budidaya dengan Rancangan Acak Lengkap (RAL) menggunakan lima perlakuan dan tiga ulangan yang diaplikasikan untuk pengendalian penyakit motile aromonas septicemia (MAS). Perlakuan tersebut adalah A (tanpa penambahan bakteri probiotik B. firmus (sebagai control), B (...

  5. Prevalence and antimicrobial susceptibilities of Vibrio, salmonella, and Aeromonas isolates from various uncooked seafoods in Thailand.

    Science.gov (United States)

    Woodring, Joseph; Srijan, Apichai; Puripunyakom, Paksathorn; Oransathid, Wilawan; Wongstitwilairoong, Boonchai; Mason, Carl

    2012-01-01

    Uncooked seafood samples were collected from open markets and supermarkets in Bangkok, Thailand, and were examined for the presence of Vibrio, Salmonella, and Aeromonas species from January to February 2008. From 120 samples, 272 bacterial isolates were identified through biochemical testing. Of all sea bass, shrimp, oyster, and blood cockle samples (30 of each) that were processed for culture, 114 (95%) samples had at least one detectable isolate of Vibrio, Salmonella, or Aeromonas, leaving only 6 (5%) samples free of them. All oyster sample (100%) had at least one pathogen, followed by sea bass (97%), blood cockles (97%), and shrimp (90%). Overall, 111 (92%) of all samples had detectable Vibrio spp., 32 (27%) had detectable Aeromonas spp., and 25 (21%) had detectable Salmonella enterica. There was no overall difference between positive samples collected from fresh markets versus supermarkets (relative risk, 0.97; 95% CI, 0.89 to 1.05). Resistance to ampicillin among isolated pathogens was relatively high (56%), while resistance to 12 other antibiotics, including azithromycin, ciprofloxacin, and trimethoprim-sulfamethoxazole, was relatively low (0, 0, and 3%, respectively). Study results indicate that uncooked seafood in Bangkok, Thailand, commonly harbors enteric pathogens and that consumption of uncooked seafood should be avoided to reduce foodborne illnesses.

  6. A culture independent method for the detection of Aeromonas sp. from water samples

    Directory of Open Access Journals (Sweden)

    Fadua Latif-Eugenín

    2016-01-01

    Full Text Available The genus Aeromonas is present in a wide variety of water environments and is recognised as potentially pathogenic to humans and animals. Members of this genus are often confused with Vibrio when using automated, commercial identification systems that are culture-dependent. This study describes a polymerase chain reaction (PCR detection method for Aeromonas that is culture- independent and that targets the glycerophospholopid-cholesterol acyltransferase (gcat gene, which is specific for this genus. The GCAT-PCR was 100% specific in artificially inoculated water samples, with a detection limit that ranged from 2.5 to 25 cfu/mL. The success at detecting this pathogen in 86 water samples using the GCAT-PCR method was identical to the conventional culturing method when a pre-enrichment step was carried out, yielding 83.7% positive samples. On the other hand, without a pre-enrichment step, only 77.9% of the samples were positive by culturing and only 15.1% with the GCATPCR. However, 83.7% positive samples were obtained for the GCAT-PCR when the water volume for the DNA extraction was increased from 400 μL to 4 mL. The proposed molecular method is much faster (5 or 29 h than the culturing method (24 or 48 h whether performed directly or after a pre-enrichment step and it will enable the fast detection of Aeromonas in water samples helping to prevent a possible transmission to humans.

  7. Toxin Production by Aeromonas sobria in Natural Environments: River Water vs. Seawater

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    Ramamurthy,Thandavarayan

    2008-12-01

    Full Text Available Aeromonas are water-borne pathogens. They are halotolerant, which means that they can survive in environments whose salt content corresponds to that of seawater (3.0% NaCl. However, the presence of Aeromonas in seawater is extremely rare compared with that in river water. In this study, we tested the ability of Aeromonas sobria to produce toxins in river water and seawater. First, we cultured A. sobria on skim milk agar plates supplemented with either river water (SARW or seawater (SASW. The bacteria grew on both plates. A clear zone around the bacteria was generated in SARW. However, such a zone was not observed in SASW, suggesting that proteases were not generated in SASW. Subsequently, we cultured A. sobria in a nutrient broth supplemented with either river water (NRW or with seawater (NSW, and examined the protease activity of their culture supernatants. The protease activity of the culture supernatant from NSW was extremely low compared to that from NRW. The immunoblotting analysis showed that serine protease (ASP was not produced by the culture in NSW. By contrast, aerolysin-like hemolysin was produced in all conditions examined in this study. This indicates that the salinity of water is deeply involved in the production of ASP by A. sobria.

  8. Anti-biogram and resistogram profiling of Aeromonas species isolated from Malaysian aquatic sources

    Directory of Open Access Journals (Sweden)

    Olumide Adedokun Odeyemi

    2013-09-01

    Full Text Available Objective: To investigate antibiotics and heavy metals resistance profile of Aeromonas species isolated from Kuala Gula and Kuala Sepetang, Perak. Methods: Isolated Aeromonas species were subjected to 12 antibiotics: penicillin G 10 units, tetracycline 30 µg, novobiocin 5 µg, nitrofurantoin 100 µg, ampicillin 10 µg, chloramphenicol 10 µg, fluconazole 25 µg, gentamicin 10 µg, streptomycin 10 µg and 25 µg, kanamycin 30 µg, and vancomycin 30 µg and 5 heavy metals: MnSO4.H2O, Cr(NO3.9H2O, CuSO4, Pb(NO32, HgCl2. Results: Results from this study revealed that isolates from the two sources-displayed varied resistance. Isolates from Kuala Sepetang showed 91%, 66%, 61%, and 52% resistance to vancomycin, Novobiocin, streptomycin and gentamycin while Kuala Gula isolates showed 76%, 93%, 28% and 14% respectively. High rate of resistance was shown to be against lead (Pb, Chromium (Cr, copper (Cu and Manganese (Mn with minimum inhibitory concentration ranging from 2 560 µg/mL to >5 120 µg/mL. Low resistance to mercury was observed among isolates from Kuala Gula. Conclusions: This study showed that there was widespread of both heavy metals and antibiotics resistance among Aeromonas isolates from the two marine sources with isolates from Kuala Sepetang showing more resistance thereby posing danger to both aquatic animals and human health.

  9. DAYA HAMBAT EKSTRAK METANOL RUMPUT LAUT (Euchema spinosum TERHADAP BAKTERI Aeromonas hydrophila

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    Y Yunus

    2009-10-01

    Full Text Available Rumput laut secara tradisional telah lama dimanfaatkan sebagai bahan makanan, kosmetik dan obat-obatan, karena kaya akan mineral, elemen makro dan elemen  mikro lainnya, disamping itu rumput laut juga berfungsi sebagai bahan antimikroba seperti penyakit bakteri Aeromonas hydrophila yang sering menginfeksi ikan pada budidaya air tawar sehingga banyak merugikan petani. Oleh karena itu, maka perlu dilakukan penelitian tentang konsentrasi ekstrak metanol rumput laut yang efektif. Tujuan dari penelitian ini adalah untuk mengetahui konsentrasi ekstrak metanol rumput laut Eucheuma spinosum yang tepat untuk menghambat pertumbuhan bakteri Aeromonas hydrophyla. Metode penelitian yang digunakan adalah metode eksperimen, Pertama menggunakan Uji MIC  konsentrasi sebagai berikut : 25%; 12,5%; 6,25%; 3,125%; 1,56%; 0,78%; 0,39%; 0,195%; 0,098%; 0,049%; 0,025%; dan 0,0125%. Kedua menggunakan Uji Cakram konsentrasi 3%, 6%, 9%, 12%, dan 0%  sebagai kontrol. Hasil uji MIC setelah dibandingkan dengan kontrol positif sangat rendah yaitu sebesar 0,049%, hasil ini menunjukkan bahwa konsentrasi tersebut menghambat pertumbuhan bakteri Aeromnas hydrophila. Pada hasil uji cakram kemampuan ekstrak rumput laut pada konsentrasi 3%, 6% dan 9% dalam menghambat bakteri Aeromons hydrophila bersifat bakteriostatik, sedangkan pada konsentrasi 12% bersifat bakteriosidal.  Kata Kunci : Eucheuma spinosum, Polifenol, Aeromonas hydrophila

  10. An investigation of the bactericidal activity of selected essential oils to Aeromonas spp.

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    Clifford E. Starliper

    2015-01-01

    Full Text Available Diseases of fishes caused by Aeromonas spp. are common, have broad host ranges and may cause high mortality. Treatments of captive-reared populations using antimicrobials are limited with concerns for bacterial resistance development and environmental dissemination. This study was done to determine whether selected plant-derived essential oils were bactericidal to Aeromonas spp. Initially, twelve essential oils were evaluated using a disk diffusion assay to an isolate of A. salmonicida subsp. salmonicida, cause of fish furunculosis. The greatest zones of inhibition were obtained with oils of cinnamon Cinnamomum cassia, oregano Origanum vulgare, lemongrass Cymbopogon citratus and thyme Thymus vulgaris. Minimum bactericidal concentrations (MBC’s were determined for these four oils, Allimed® (garlic extract, Allium sativum and colloidal silver to sixty-nine isolates representing nine Aeromonas spp. The lowest mean MBCs (0.02–0.04% were obtained with three different sources of cinnamon oil. MBCs for three sources of oregano and lemongrass oils ranged from 0.14% to 0.30% and 0.10% to 0.65%, respectively, and for two thyme oils were 2.11% and 2.22%. The highest concentration (5% of Allimed® tested resulted in MBCs to twelve isolates. A concentration of silver greater than 15 mg/L would be required to determine MBCs for all but one isolate.

  11. Synthesis and evaluation of bactericidal properties of CuO nanoparticles against Aeromonas hydrophila

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    Sayedeh Fatemeh Shaffiey

    2014-04-01

    Full Text Available   Objective(s: CuO is one of the most important transition metal oxides due to its captivating properties. It is used in various technological applications such as high critical temperature superconductors, gas sensors, in photoconductive applications, and so on. Recently, it has been used as an antimicrobial agent against various bacterial species.   Materials and Methods: Here, we synthesized CuO nanoparticles (NPs and explored the antibacterial activity of CuO NPs preparation. Results: Single crystalline nanoparticles of copper oxide having almost uniform particle size of 5-6 nm has been synthesized by a facile and versatile route. XRD spectra confirmed the formation of single phase CuO NPs. Transmission electron microscopy results corroborate well with XRD results. The technique employed is free from toxic solvents, organics and amines, is based on a simple reaction of copper sulfate and de-ionized water (DI, and their bactericidal effects against of Aeromonas hydrophila ATCC 7966T bacteria were investigated. Minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC with liquid culture for all of the Aeromonas hydrophila culture Medias was done. Conclusion: Present study confirms that Copper oxide nanoparticles have great promise as antimicrobial agent against Aeromonas hydrophila

  12. Aeromonas hydrophila-associated septicemia in captive crocodiles (Crocodylus johnstoni and Crocodylus porosus).

    Science.gov (United States)

    Roh, Yoon-Seok; Park, Heejin; Cho, Hyun-Ung; Cho, Ara; Islam, Mohammad Rafiqul; Cho, Ho-Seong; Lim, Chae Woong; Kim, Bumseok

    2011-12-01

    Five 25-yr-old crocodiles (Crocodylus johnstoni and Crocodylus porosus) were diagnosed with Aeromonas hydrophila-associated septicemia accelerated by improper thermoregulation. At necropsy, pulmonary congestion and pleural effusion were the main lesions in the thorax. Necrotizing enteritis, intestinal hemorrhage, fibrinous serositis, hepatitis, and pancreatitis were observed in the abdominal cavities of all five crocodiles. Aeromonas hydrophila was identified in the pleural effusions and abdominal ascites of all necropsied crocodiles by using an API system 20NE. Aeromonas hydrophila infection and evaluation of virulence were confirmed by polymerase chain reaction targeting the 16S rRNA and extracellular hemolysin gene. The crocodiles in the present case were housed in an indoor facility at a private zoo that failed to optimize land and water portions of the enclosure, exposing the animals to impeded thermoregulation, and it is suggested that the pathogenesis was accelerated by the improper thermoregulation-induced stress. This is the first description of A. hydrophila pathogenicity associated with impeded thermoregulation in reptiles.

  13. Anti-biogram and resistogram profiling of Aeromonas species isolated from Malaysian aquatic sources

    Institute of Scientific and Technical Information of China (English)

    Olumide Adedokun Odeyemi; Asmat Ahmad

    2013-01-01

    Objective: To investigate antibiotics and heavy metals resistance profile of Aeromonas species isolated from Kuala Gula and Kuala Sepetang, Perak. Methods: Isolated Aeromonas species were subjected to 12 antibiotics: penicillin G 10 units, tetracycline 30 µg, novobiocin 5 µg, nitrofurantoin 100 µg, ampicillin 10 µg, chloramphenicol 10 µg, fluconazole 25 µg, gentamicin 10 µg, streptomycin 10 µg and 25 µg, kanamycin 30 µg, and vancomycin 30 µg and 5 heavy metals: MnSO4.H2O, Cr(NO3).9H2O, CuSO4, Pb(NO3)2, HgCl2. Results: Results from this study revealed that isolates from the two sources-displayed varied resistance. Isolates from Kuala Sepetang showed 91%, 66%, 61%, and 52% resistance to vancomycin, Novobiocin, streptomycin and gentamycin while Kuala Gula isolates showed 76%, 93%, 28% and 14% respectively. High rate of resistance was shown to be against lead (Pb), Chromium (Cr), copper (Cu) and Manganese (Mn) with minimum inhibitory concentration ranging from 2 560 µg/mL to>5120 µg/mL. Low resistance to mercury was observed among isolates from Kuala Gula. Conclusions: This study showed that there was widespread of both heavy metals and antibiotics resistance among Aeromonas isolates from the two marine sources with isolates from Kuala Sepetang showing more resistance thereby posing danger to both aquatic animals and human health.

  14. SELEKSI KANDIDAT PROBIOTIK ANTI AEROMONAS HYDROPHILA UNTUK PENGENDALIAN PENYAKIT IKAN AIR TAWAR

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    Angela Mariana Lusiastuti

    2012-08-01

    Full Text Available Secara dasar ada tiga model kerja probiotik yaitu menekan populasi mikroba melalui kompetisi dengan memproduksi senyawa anti-mikroba atau melalui kompetisi nutrisi dan tempat pelekatan di dinding usus, mengubah keseimbangan metabolisme mikroba dengan meningkatkan atau menurunkan aktivitas enzim dan menstimulasi imunitas dengan meningkatkan antibodi dan aktivitas makrofag. Tujuan penelitian ini adalah memperoleh mikroba yang berpotensi sebagai kandidat probiotik untuk dapat diaplikasikan di dalam menekan atau menghambat bakteri patogen sebagai langkah pengendalian penyakit pada ikan air tawar. Penelitian ini terdiri atas dua tahap, tahap pertama adalah tahap seleksi yang dimulai dari koleksi dan isolasi bakteri kandidat probiotik dan tahap kedua adalah tahap pengujian bakteri kandidat probiotik secara in vitro menggunakan metode daya hambat dan menguji daya patogenisitas bakteri. Total isolat bakteri yang diperoleh adalah 72 isolat, dan hanya enam isolat terpilih sebagai kandidat probiotik anti Aeromonas hydrophila. Probiotik anti A. hydrophila adalah sebagai berikut: Chromobacterium lividum, Alcaligenes faecalis, Aeromonas caviae, Bacteriodes serpens, Bacillus firmus, Aeromonas caviae = A. hydrophila Sub sp. Anaerogenes.

  15. Occurrence of potential pathogenic Aeromonas species in tropical seafood, aquafarms and mangroves off Cochin coast in South India

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    Alphonsa Vijaya Joseph

    2013-12-01

    Full Text Available Background: The genus Aeromonas include gram-negative, motile, facultative anaerobic, rod shaped and oxidase positive bacteria comprising several species, associated with the aquatic environment. Aeromonas species have been implicated in human pathogenesis and are linked with gastroenteritis, muscle infections, septicemia, and skin diseases. In fish they are renowned as enteric pathogens causing haemorrhagic septicemia, fin rot, soft tissue rot and furunculosis resulting in major die-offs and fish kills. Aim: This study reports the occurrence of potential pathogenic Aeromonas sp. in tropical seafood (Squids, Prawns and Mussels, aquafarms and mangroves of Cochin, Kerala, South India. Materials and Methods :Tropical seafood (Squid, Prawn and Mussel, sediment and water samples from aquafarms and associated mangroves were screened for Aeromonas contamination. The isolates were identified by 16S rDNA sequence analysis and subjected to morphological and biochemical characterization. Haemolytic assay was used for determining pathogenicity of the organisms. Antibiotic susceptibility against 12 antibiotics were performed and the MAR index was calculated. Results: A total of 134 isolates were recovered from the samples of which 15 were identified as Aeromonas species by 16S rDNA sequence analysis and were assigned to 5 species namely, A. hydrophila, A. enteropelogenes, A. caviae, A. punctataand A. aquarorium. Morphological, biochemical and phylogenetic analyses revealed relatedness and variability among the strains. All the isolates were haemolytic on blood agar indicating their pathogenicity. The isolates exhibited varying degrees of resistance to vancomycin (86.66%, ampicillin (46.66%, nalidixic acid (20%, tetracycline (6.66%, co-trimaxozole (6.66% and rifampicin (6.66% and were susceptible to antibiotics like gentamycin, streptomycin, trimethoprim, azithromycin, cefixime and chloramphenicol. 20% of Aeromonas sp. showed MAR index > 0.2 indicative of the

  16. Multidrug-resistant (MDR) Aeromonas recovered from the metropolitan area of Valencia (Spain): diseases spectrum and prevalence in the environment.

    Science.gov (United States)

    Esteve, C; Alcaide, E; Giménez, M J

    2015-01-01

    Aeromonas infections are rare in Europe and often related to traveller's diarrhoea. A total of 185 Aeromonas isolates from river water, fish and clinical sources, recovered during a 1-year period, were used to investigate the disease spectrum and impact of multidrug-resistant (MDR) strains. They were all identified by biochemical tests and 25% of them were also identified by sequencing of the 16S rRNA gene. The minimum inhibitory concentrations (MICs) of 21 antimicrobials were determined for all isolates by broth microdilution/E-strips methods, and susceptibility was assessed according to the Clinical and Laboratory Standards Institute (CLSI). Strains pathogenicity was determined by using Swiss Webster mice as the animal model. Aeromonas diseases had an incidence of around 20 cases/million inhabitants in the metropolitan area of Valencia (Spain). Acute gastroenteritis in children with no history of travel abroad was the main pathology. These cases were related to A. caviae, A. veronii biovar sobria, A. hydrophila and A. dhakensis. A significant incidence of A. caviae in humans was found, while the other species were equally present in clinical and environmental origins. A. jandaei, A. bestiarum and A. media had mainly an environmental distribution. The prevalence of MDR Aeromonas was maximal in clinical samples, and resistance phenotypes were significantly related to this source. 7.2% of environmental Aeromonas was resistant to at least five drugs; most of them were moderately virulent for mice and, in addition, belonged to clinically significant species. The present study demonstrates a diseases spectrum similar to that reported in tropical countries, and also that pathogenic and heavily MDR Aeromonas are present in environmental reservoirs. MDR Aeromonas from any source analysed were susceptible to aztreonam, netilmicin, cefotaxime, ceftazidime, cefepime and fluoroquinolones.

  17. Isolation and Characterization of a New Subspecies of Aeromonas salmonicida (Aeromonas salmonicida subsp.Flounderacida subsp.Nov.) from Stone Flounder(Kareius bicoloratus L.)

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaojun(张晓君); Zhan Wenbin; Chen Cuizhen; Fang Hai

    2004-01-01

    Biological properties were studied to appropriate pathogenic bacteria which were isolated from di-seased (or dead) stone flounder (Kareius bicoloratus L.) which expressed bacterial septicaemia, including morphological characteristics, colony characteristics, physiological and biochemical characteristics and serum homology of isolates, the results showed that the isolates belonged to a new subspecies of A.salmonicida. In addition, the representative strains have been re-checked and detected the mol% G+C ratio of the DNA by China Center for Type Culture Collection (CCTCC), the examined strains were also regarded as a new subspecies of A.salmonicida, and designated as Aeromonas salmonicida subsp. flounderacida subsp.nov.by its isolated fish (Kareius bicoloratus). Molecular identification of analysis of the nucleotide sequence of the 16S rRNA gene were applied, the results showed high similarity (99%) with the 16S rRNA gene of Aeromonas salmonicida from GenBank database. Cluster analysis of phylogenetic tree revealed that the representative strain formed separately bootstrap-supported cluster.

  18. Prevalence, virulence and antimicrobial resistance patterns of Aeromonas spp. isolated from children with diarrhea

    Science.gov (United States)

    Soltan Dallal, Mohammad Mehdi; Mazaheri Nezhad Fard, Ramin; Kavan Talkhabi, Morteza; Aghaiyan, Leyla; Salehipour, Zohre

    2016-01-01

    Background Aeromonas spp. cause various intestinal and extraintestinal diseases. These bacteria are usually isolated from fecal samples, especially in children under five years old. The aim of this study was to assess the prevalence of Aeromonas spp. and their antimicrobial resistance profile in children with diarrhea referred to the Children Medical Center in Tehran, between 2013 and 2014. Methods A total number of 391 stool samples were collected from children with ages between 1 day and 14 years old, with diarrhea (acute or chronic), referred to the Children Hospital, Tehran, Iran, between 2013 and 2014. Samples were enriched in alkaline peptone water broth for 24 hours at 37 °C and then cultured. Suspicious colonies were analyzed through biochemical tests. Furthermore, antimicrobial susceptibility tests were carried out for the isolates. Isolates were further studied for act, ast, alt, aerA and hlyA virulence genes using polymerase chain reaction. Results In total, 12 isolates (3.1%) were identified as Aeromonas spp.; all were confirmed using the API-20E test. Of these isolates, five A. caviae (42%), four A. veronii (33%) and three A. hydrophila (25%) were identified in cases with gastroenteritis. Second to ampicillin (which was included in the growth medium used), the highest rate of antimicrobial resistance was seen against nalidixic acid and trimethoprim-sulfamethoxazole (5 isolates each, 41.6%) and the lowest rate of antimicrobial resistance was seen against gentamicin, amikacin and cefepime (none of the isolates). Results included 76.4% act, 64.7% ast, 71.5% alt, 83.3% aerA and 11.7% hlyA genes. Conclusion Aeromonas spp. are important due to their role in diarrhea in children; therefore, isolation and identification of these fecal pathogens should seriously be considered in medical laboratories. Since virulence genes play a significant role in gastroenteritis symptoms caused by these bacteria, Aeromonas species that include virulence genes are potentially

  19. Mutation in the S-ribosylhomocysteinase (luxS) gene involved in quorum sensing affects biofilm formation and virulence in a clinical isolate of Aeromonas hydrophila

    Science.gov (United States)

    A diarrheal isolate SSU of Aeromonas hydrophila produces a cytotoxic enterotoxin (Act) with cytotoxic, enterotoxic, and hemolytic activities. Our laboratory has characterized from the above Aeromonas strain, in addition to Act, the type 3- and T6-secretion systems and their effec...

  20. Predicting Virulence of Aeromonas Isolates Based-on Changes in Transcription of c-jun and c-fos in Human Tissue Culture Cells

    Science.gov (United States)

    Aims: To assess virulence of Aeromonas isolates based on the change in regulation of c-jun and c-fos in the human intestinal tissue culture cell line Caco-2. Methods and Results: Aeromonas cells were added to Caco-2 cells at approximately a one to one ratio. After 1, 2 and 3 ...

  1. Complete genome sequence of the highly virulent Aeromonas hydrophila AL09-71 isolated from disease channel catfish from West Alabama

    Science.gov (United States)

    The highly virulent Aeromonas hydrophila isolate AL09-71 was cultured from infected channel catfish during the 2009 disease outbreak in West Alabama. The complete genome of this highly virulent Aeromonas hydrophila isolate AL09-71 is 5,023,861 bp in size. The genome has 4489 coding sequences, 11 cop...

  2. Aeromonas surface glucan attached through the O-antigen ligase represents a new way to obtain UDP-glucose.

    Directory of Open Access Journals (Sweden)

    Susana Merino

    Full Text Available We previously reported that A. hydrophila GalU mutants were still able to produce UDP-glucose introduced as a glucose residue in their lipopolysaccharide core. In this study, we found the unique origin of this UDP-glucose from a branched α-glucan surface polysaccharide. This glucan, surface attached through the O-antigen ligase (WaaL, is common to the mesophilic Aeromonas strains tested. The Aeromonas glucan is produced by the action of the glycogen synthase (GlgA and the UDP-Glc pyrophosphorylase (GlgC, the latter wrongly indicated as an ADP-Glc pyrophosphorylase in the Aeromonas genomes available. The Aeromonas glycogen synthase is able to react with UDP or ADP-glucose, which is not the case of E. coli glycogen synthase only reacting with ADP-glucose. The Aeromonas surface glucan has a role enhancing biofilm formation. Finally, for the first time to our knowledge, a clear preference on behalf of bacterial survival and pathogenesis is observed when choosing to produce one or other surface saccharide molecules to produce (lipopolysaccharide core or glucan.

  3. Aeromonas surface glucan attached through the O-antigen ligase represents a new way to obtain UDP-glucose.

    Science.gov (United States)

    Merino, Susana; Bouamama, Lamiaa; Knirel, Yuriy A; Senchenkova, Sofya N; Regué, Miguel; Tomás, Juan M

    2012-01-01

    We previously reported that A. hydrophila GalU mutants were still able to produce UDP-glucose introduced as a glucose residue in their lipopolysaccharide core. In this study, we found the unique origin of this UDP-glucose from a branched α-glucan surface polysaccharide. This glucan, surface attached through the O-antigen ligase (WaaL), is common to the mesophilic Aeromonas strains tested. The Aeromonas glucan is produced by the action of the glycogen synthase (GlgA) and the UDP-Glc pyrophosphorylase (GlgC), the latter wrongly indicated as an ADP-Glc pyrophosphorylase in the Aeromonas genomes available. The Aeromonas glycogen synthase is able to react with UDP or ADP-glucose, which is not the case of E. coli glycogen synthase only reacting with ADP-glucose. The Aeromonas surface glucan has a role enhancing biofilm formation. Finally, for the first time to our knowledge, a clear preference on behalf of bacterial survival and pathogenesis is observed when choosing to produce one or other surface saccharide molecules to produce (lipopolysaccharide core or glucan).

  4. Two novel temperate bacteriophages co-existing in Aeromonas sp. ARM81 - characterization of their genomes, proteomes and DNA methyltransferases.

    Science.gov (United States)

    Dziewit, Lukasz; Radlinska, Monika

    2016-08-01

    Aeromonas species are causative agents of a wide spectrum of diseases in animals and humans. Although these bacteria are commonly found in various environments, little is known about their phages. Thus far, only one temperate Aeromonas phage has been characterized. Whole-genome sequencing of an Aeromonas sp. strain ARM81 revealed the presence of two prophage clusters. One of them is integrated into the chromosome and the other was maintained as an extrachromosomal, linear plasmid-like prophage encoding a protelomerase. Both prophages were artificially and spontaneously inducible. We separately isolated both phages and compared their genomes with other known viruses. The novel phages show no similarity to the previously characterized Aeromonas phages and might represent new evolutionary lineages of viruses infecting Aeromonadaceae. Apart from the comparative genomic analyses of these phages, complemented with their structural and molecular characterization, a functional analysis of four DNA methyltransferases encoded by these viruses was conducted. One of the investigated N6-adenine-modifying enzymes shares sequence specificity with a Dam-like methyltransferase of its bacterial host, while another one is non-specific, as it catalyzes adenine methylation in various sequence contexts. The presented results shed new light on the diversity of Aeromonas temperate phages.

  5. Aeromonas spp. isolated from oysters (Crassostrea rhizophorea from a natural oyster bed, Ceará, Brazil Aeromonas spp. isoladas de ostras (Crassostrea rhizophorea coletadas em um criadouro natural, Ceará, Brazil

    Directory of Open Access Journals (Sweden)

    Norma S. Evangelista-Barreto

    2006-06-01

    Full Text Available Between April and October 2002, thirty fortnightly collections of oysters (Crassostrea rhizophorea from a natural oyster bed at the Cocó River estuary in the Sabiaguaba region (Fortaleza, Ceará, Brazil were carried out, aiming to isolate Aeromonas spp. strains. Oyster samples were submitted to the direct plating (DP and the presence/absence (P/A methods. Aeromonas were identified in 15 (50% samples analyzed by the DP method and in 13 (43% analyzed by the P/A method. A. caviae, A. eucrenophila, A. media, A. sobria, A. trota, A. veronii bv. sobria, A. veronii bv. veronii and Aeromonas sp. were isolated. The predominant species was A. veronii (both biovars, which was identified in 13 (43% samples, followed by A. media in 11 (37% and A. caviae in seven (23%. From the 59 strains identified, 28 (48% presented resistance to at least one of the eight antibiotics tested.Foram realizadas 30 coletas quinzenais, entre abril e outubro de 2002, de ostras (Crassostrea rhizophorea de um criadouro natural, no estuário do rio Cocó (Fortaleza/Ceará/Brasil, objetivando-se isolar cepas de Aeromonas spp. As amostras de ostras foram submetidas aos métodos de plaqueamento direto (PD e presença/ausência (P/A. Foram identificadas Aeromonas em 15 (50% amostras analisadas pelo método PD e em 13 (43% pelo método P/A. Foram isoladas: A. caviae, A. eucrenophila, A. media, A. sobria, A. trota, A. veronii bv. sobria, A. veronii bv. veronii e Aeromonas sp. A espécie predominate foi A. veronii (ambos biovars, identificada em 13 (43% amostras, seguida de A. media em 11 (37% e A. caviae em 7 (23%. Das 59 cepas identificadas, 28 (48% apresentaram resistência a pelo menos um, dos oitos antibióticos testados.

  6. Novo meio seletivo-indicador para detecção de Aeromonas e Plesiomonas: ágar UNISC New selective indicator medium for detection of Aeromonas and Plesiomonas: UNISC agar

    Directory of Open Access Journals (Sweden)

    Marion Pereira da Rocha

    2008-08-01

    Full Text Available Avaliou-se um novo meio seletivo-indicador (ágar UNISC para o isolamento de enteropatógenos clássicos e Aeromonas e Plesiomonas shigelloides. A capacidade de fermentação da xilose é indicada pela coloração amarela (fermentadores ou azul (não fermentadores que, aliada à prova da oxidase, constitui-se em indicador para a detecção de Aeromonas spp e Plesiomonas shigelloides. A produtividade e seletividade, avaliadas pelos índice de contagem absoluta e índice de contagem relativa indicam-no como uma alternativa aos coprocultivos clássicos porque permite, num só meio, o isolamento de Escherichia coli, Shigella spp, Salmonella spp, bem como, Aeromonas spp e Plesiomonas shigelloides, favorecendo o diagnóstico laboratorial das gastroenterites.We evaluated a new selective indicator medium (UNISC Agar for isolation of classical enteropathogens, Aeromonas spp and Plesiomonas shigelloides. The xylose fermentation capacity is indicated by a yellow color (fermenting agents or blue (no fermenting agent. This, together with the oxidase test, establishes it as an indicator for detecting Aeromonas and Plesiomonas shigelloides. Its productivity and selectivity, as assessed using the absolute count index and relative count index, indicate it as an alternative to the classical feces culturing media. This is because, in a single medium, it enables isolation of Escherichia coli, Shigella spp and Salmonella spp, in addition to Aeromonas and Plesiomonas shigelloides, thereby favoring the laboratory diagnosis of gastroenteritis.

  7. Quinolone resistant Aeromonas spp. as carriers and potential tracers of acquired antibiotic resistance in hospital and municipal wastewater.

    Science.gov (United States)

    Varela, Ana Rita; Nunes, Olga C; Manaia, Célia M

    2016-01-15

    Members of the genus Aeromonas are recognized carriers of antibiotic resistance in aquatic environments. However, their importance on the spread of resistance from hospital effluents to the environment is poorly understood. Quinolone resistant Aeromonas spp. (n = 112) isolated from hospital effluent (HE) and from raw (RWW) and treated wastewater (TWW) of the receiving urban wastewater treatment plant (UWTP) were characterized. Species identification and genetic intraspecies diversity were assessed based on the 16S rRNA, cpn60 and gyrB genes sequence analysis. The antibiotic resistance phenotypes and genotypes (qnrA, qnrB, qnrC, qnrD, qnrS, qnrVC; qepA; oqxAB; aac(6′)-Ib-cr; blaOXA; incU) were analyzed in function of the origin and taxonomic group. Most isolates belonged to the species Aeromonas caviae and Aeromonas hydrophila (50% and 41%, respectively). The quinolone and the beta-lactamase resistance genes aac(6′)-Ib-cr and blaOXA, including gene blaOXA-101, identified for the first time in Aeromonas spp., were detected in 58% and 56% of the isolates, respectively, with identical prevalence in HE and UWTP wastewater. In contrast, the gene qnrS2 was observed mainly in isolates from the UWTP (51%) and rarely in HE isolates (3%), suggesting that its origin is not the clinical setting. Bacterial groups and genes that allow the identification of major routes of antibiotic resistance dissemination are valuable tools to control this problem. In this study, it was concluded that members of the genus Aeromonas harboring the genes aac(6′)-Ib-cr and blaOXA are relevant tracers of antibiotic resistance dissemination in wastewater habitats, while those yielding the gene qnrS2 allow the traceability from non-clinical sources.

  8. Characterization of Aeromonas strains isolated from Indian foods using rpoD gene sequencing and whole cell protein analysis.

    Science.gov (United States)

    Nagar, Vandan; Shashidhar, Ravindranath; Bandekar, Jayant R

    2013-04-01

    Aeromonas are responsible for causing gastroenteritis and extra-intestinal infections in humans. Twenty-two Aeromonas strains isolated from different food sources were re-identified up to species level using rpoD gene sequence analysis. Biochemical tests and 16S rRNA gene sequencing were insufficient to identify Aeromonas till species level. However, incorporation of additional biochemical tests lead to correct identification of 95.5 % strains up to species level. The 16S rRNA gene sequencing was useful to identify Aeromonas isolates at the genus level only. Sequences of the rpoD gene showed greater discriminatory power than 16S rRNA gene and provided conclusive discrimination of the strains for which the phenotypic species identification was uncertain. All these 22 strains were accurately identified up to species level by rpoD gene as A. salmonicida (6), A. veronii bv. veronii (4), A. caviae (3), A. hydrophila (2), A. veronii bv. sobria (2), A. jandaei (1), A. trota (1), A. sobria (1), A. allosaccharophila (1) and A. bivalvium (1). All these strains were also characterized using whole cell protein (WCP) analysis by gradient SDS-PAGE and showed different whole cell protein (WCP) profile [22-28 polypeptide bands (~10 to >97 kDa)], indicating high genetic diversity. The present work emphasizes the use of molecular methods such as rpoD gene sequencing along with comprehensive biochemical tests for the rapid and accurate identification of Aeromonas isolates till species level. The WCP profile can be subsequently used to characterize Aeromonas isolates below species level.

  9. ESTUDIO DE LA PATOGENICIDAD DE DIFERENTES ESPECIES DE Aeromonas EN LA TRUCHA ARCOÍRIS (Oncorhynchus mykiss)

    OpenAIRE

    Zepeda Velázquez, Andrea Paloma

    2015-01-01

    El género Aeromonas incluye bacterias que habitan naturalmente el medio acuático, capaces de infectar diferentes especies animales, incluido el humano. Las enfermedades causadas por este género ocasionan pérdidas económicas significativas para la industria trutícola. Con el objeto de conocer la patogenicidad y virulencia de diferentes especies de Aeromonas spp., en la trucha arcoíris (Oncorhynchus mykiss), en el presente estudio se caracterizaron las lesiones macroscópicas e histológicas pres...

  10. Impact of thermal loading and other water quality parameters on the epizootiology of Aeromonas hydrophila infections of centrarchids. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Esch, G.W.; Hazen, T.C.

    1983-01-01

    Red-sore disease is a rather recent problem for those involved in the sport and commercial fishing industries in the southeastern United States. The causative, or etiological, agent for red-sore disease is the widespread and commonly occurring bacterium, Aeromonas hydrophila. The disease is characterized by both external and internal lesions with serious damage to internal organs ultimately causing death of the host. Evidence points to the existence of several strains of Aeromonas hydrophila with some more virulent than others. The prevalence of the disease is related to elevated water temperature and body condition.

  11. Evidence of increased antibiotic resistance in phylogenetically-diverse Aeromonas isolates from semi-intensive fish ponds treated with antibiotics

    Directory of Open Access Journals (Sweden)

    Hemant J Patil

    2016-11-01

    Full Text Available The genus Aeromonas is ubiquitous in aquatic environments encompassing a broad range of fish and human pathogens. Aeromonas strains are known for their enhanced capacity to acquire and exchange antibiotic resistance genes and therefore, are frequently targeted as indicator bacteria for monitoring antimicrobial resistance in aquatic environments. This study evaluated temporal trends in Aeromonas diversity and antibiotic resistance in two adjacent semi-intensive aquaculture facilities to ascertain effects of antibiotic treatment on antimicrobial resistance. In the first facility, sulfadiazine-trimethoprim was added prophylactically upon fingerling stocking and water column-associated Aeromonas were monitored periodically over an eleven-month fish-fattening cycle to assess temporal dynamics in taxonomy and antibiotic resistance. In the second facility, Aeromonas were isolated from fish skin ulcers sampled over a three-year period and from pond water samples to assess associations between pathogenic strains to those in the water column. A total of 1200 Aeromonas spp. were isolated, initially screened for sulfadiazine resistance and further screened against five additional antibiotics. In both facilities, strong correlations were observed between sulfadiazine resistance and trimethoprim and tetracycline resistances, whereas correlations between sulfadiazine resistance and ceftriaxone, gentamycin and chloramphenicol resistances were low. Abundance of multi-drug resistant strains as well as sul1, tetA and intI1 gene-harboring strains was significantly higher in profiles sampled during the fish cycle than those isolated prior to stocking and these genes were extremely abundant in the pathogenic strains. Five phylogenetically-distinct Aeromonas clusters were revealed using partial rpoD gene sequence analysis. Interestingly, prior to fingerling stocking the diversity of water column strains was high, and representatives from all five clusters were

  12. Emerging extra-intestinal infections with Aeromonas hydrophila in coastal region of southern Karnataka

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    Mukhopadhyay C

    2008-01-01

    Full Text Available Background: Aeromonas species are gram-negative rods usually isolated from the gastrointestinal tract. They have been occasionally reported as a cause of extra-intestinal infections such as cellulitis, cholangitis, necrotizing fascitis, meningitis, bacteremia, or peritonitis in both immunocompetent and immunocompromised patients . Aim: To determine the role and possible pathogenesis of Aeromonas in extra-intestinal infections.Settings and Design: Retrospective analysis carried out at Kasturba Hospital Manipal, Karnataka in the months of January and February 2007. Materials and Methods: Clinical manifestations and management of eight cases of extra-intestinal infections caused by A. hydrophila , from the south Karnataka coastal region were reviewed. The isolates were identified with the help of biochemical tests using standard guidelines.Results: All patients acquired Aeromonas infections in the community. Five (62.5% had underlying illnesses, such as liver disease, diabetes mellitus or malignancy. Five (62.5% had polymicrobial infections, and three (37.5% were complicated with bacteremia. These included three patients with ulcers or abscess over the lower leg, two with cellulitis due to snake bite and one each with pelvic inflammatory disease, spontaneous bacterial peritonitis and pneumonia. A. hydrophila was found to be a causative agent of pelvic inflammatory disease or cellulitis following sea snake bite, and such a clinical scenario has not been previously described. Seven patients survived the illness. Conclusions: Isolation of A. hydrophila from extra-intestinal specimens demands utmost clinical and microbiological vigilance in diagnosis, since the organism can cause serious infections among immunocompromised as well as immunocompetent individuals.

  13. Functional genomic characterization of virulence factors from necrotizing fasciitis-causing strains of Aeromonas hydrophila.

    Science.gov (United States)

    Grim, Christopher J; Kozlova, Elena V; Ponnusamy, Duraisamy; Fitts, Eric C; Sha, Jian; Kirtley, Michelle L; van Lier, Christina J; Tiner, Bethany L; Erova, Tatiana E; Joseph, Sandeep J; Read, Timothy D; Shak, Joshua R; Joseph, Sam W; Singletary, Ed; Felland, Tracy; Baze, Wallace B; Horneman, Amy J; Chopra, Ashok K

    2014-07-01

    The genomes of 10 Aeromonas isolates identified and designated Aeromonas hydrophila WI, Riv3, and NF1 to NF4; A. dhakensis SSU; A. jandaei Riv2; and A. caviae NM22 and NM33 were sequenced and annotated. Isolates NF1 to NF4 were from a patient with necrotizing fasciitis (NF). Two environmental isolates (Riv2 and -3) were from the river water from which the NF patient acquired the infection. While isolates NF2 to NF4 were clonal, NF1 was genetically distinct. Outside the conserved core genomes of these 10 isolates, several unique genomic features were identified. The most virulent strains possessed one of the following four virulence factors or a combination of them: cytotoxic enterotoxin, exotoxin A, and type 3 and 6 secretion system effectors AexU and Hcp. In a septicemic-mouse model, SSU, NF1, and Riv2 were the most virulent, while NF2 was moderately virulent. These data correlated with high motility and biofilm formation by the former three isolates. Conversely, in a mouse model of intramuscular infection, NF2 was much more virulent than NF1. Isolates NF2, SSU, and Riv2 disseminated in high numbers from the muscular tissue to the visceral organs of mice, while NF1 reached the liver and spleen in relatively lower numbers on the basis of colony counting and tracking of bioluminescent strains in real time by in vivo imaging. Histopathologically, degeneration of myofibers with significant infiltration of polymorphonuclear cells due to the highly virulent strains was noted. Functional genomic analysis provided data that allowed us to correlate the highly infectious nature of Aeromonas pathotypes belonging to several different species with virulence signatures and their potential ability to cause NF.

  14. A foodborne outbreak of Aeromonas hydrophila in a college, Xingyi City, Guizhou, China, 2012

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    Guang Zeng

    2012-12-01

    Full Text Available Background: On 12 May 2012, over 200 college students with acute diarrhoea were reported to the Guizhou Center for Disease Control and Prevention. We conducted an investigation to identify the agent and mode of transmission and to recommend control measures.Methods: A suspected case was a person at the college with onset of more than two of the following symptoms: diarrhoea (more than three loose stools in 24 hours, abdominal pain, vomiting or fever (> 37.5C between 6 and 15 May 2012. A confirmed case also had a positive Aeromonas hydrophila culture from a stool sample. A retrospective-cohort study of 902 students compared attack rates (AR by dining place, meals and food history. We reviewed the implicated premise, its processes and preparation of implicated food.Results: We identified 349 suspected cases (AR = 14% and isolated Aeromonas hydrophila from three stools of 15 cases. Students who ate in cafeteria A were more likely to be ill compared to those eating in other places (relative risk [RR]: 3.1, 95% confidence interval [CI]: 2.0–4.8. The cohort study implicated cold cucumber (RR: 2.6, 95% CI: 2.0–3.3 and houttuynia dishes (RR: 1.8, 95% CI: 1.4–2.3. Environmental investigation showed that vegetables were washed in polluted water from a tank close to the sewage ditch, then left at 30°C for two hours before serving. The Escherichia coli count of the tank was well above the standard for drinking water.Conclusion: This outbreak of Aeromonas hydrophila was most probably caused by salad ingredients washed in contaminated tank water. We recommended enhancing training of foodhandlers, ensuring tanks and sewerage systems comply with appropriate standards and adequate monitoring of drinking water sources.

  15. Effect of the Glutaraldehyde on the Bacteriostatic and Bactericide of Aeromonas%戊二醛对气单胞菌的抑菌杀菌效果研究

    Institute of Scientific and Technical Information of China (English)

    谭凤霞; 陈和东; 叶聪

    2011-01-01

    [目的]研究戊二醛对气单胞菌的杀菌效果,为戊二醛在水产养殖上的合理使用提供依据.[方法]以气单胞菌属标准株ATCC7966和分离自养殖环境及患病鱼的气单胞菌为试验菌株,通过肉汤二倍稀释法研究.[结果]戊二醛在低浓度时能抑制气单胞菌的生长增殖,高浓度杀灭细菌,其对7株气单胞菌的最小抑菌浓度(MIC)均为7.8mg/L,其最小杀菌浓度为62.5 mg/L( ATCC7966、Aeromonas sp.T3、Aeromonas sp.T5、Aeromonas sp.T6)和125 mg/L( Aeromonas sp.T1、Aeromonas sp.T2、Aeromonas sp.T4).[结论]为戊二醛的合理使用提供一定的依据.%[Objective] The basis of the reasonable utilization of glutaraldehyde in aquaculture production was provided through the research on its effect on the bactericide of Aeromonas. [Method] The standard strain of Aeromonas - - ATCC7966 and the Aeromonas strain isolated from fish - raising environment or from diseased fish was taken as the tested strain and the efficacy of the glutaraldehyde on the bacteriostatic and bactericide of Aeromonas was determined with the method of double broth dilution. [ Results ] The results showed that the glutaraldehyde could inhibit the growth of bacterium at the low concentration and kill the bacterium at the high concentration. The minimal inhibitory concentration ( MIC) of glutaraldehyde to 7 Aeromonas strains was 7. 8mg/l and the minimal bactericidal concentration( MBC) of glutaraldehyde to 4 Aeromonas strains including ATCC7966, Aeromonas sp. T3, Aeromonas sp. T5 and Aeromonas sp. T6 was 62.5 mg/1 and 3 Aeromonas strains including Aeromonas sp. Tl, Aeromonas sp. T2 and Aeromonas sp. T4 was 125mg/l. [ Conclusion] The experimental results could provide the scientific basis of the reasonable application of glutaraldehyde.

  16. Characterization of integrons and tetracycline resistance determinants in Aeromonas spp. isolated from South African aquaculture systems.

    Science.gov (United States)

    Jacobs, Liezl; Chenia, Hafizah Y

    2007-03-20

    An increasing incidence of multidrug resistance amongst Aeromonas spp. isolates, which are both fish pathogens and emerging opportunistic human pathogens, has been observed worldwide. This can be attributed to the horizontal transfer of mobile genetic elements, viz.: plasmids and class 1 integrons. The antimicrobial susceptibilities of 37 Aeromonas spp. isolates, from tilapia, trout and koi aquaculture systems, were determined by disc-diffusion testing. The plasmid content of each isolate was examined using the alkaline lysis protocol. Tet determinant type was determined by amplification using two degenerate primer sets and subsequent HaeIII restriction. The presence of integrons was determined by PCR amplification of three integrase genes, as well as gene cassettes, and the qacEDelta1-sulI region. Thirty-seven Aeromonas spp. isolates were differentiated into six species by aroA PCR-RFLP, i.e., A. veronii biovar sobria, A. hydrophila, A. encheleia, A. ichtiosoma, A. salmonicida, and A. media. High levels of resistance to tetracycline (78.3%), amoxicillin (89.2%), and augmentin (86.5%) were observed. Decreased susceptibility to erythromycin was observed for 67.6% of isolates. Although 45.9% of isolates displayed nalidixic acid resistance, majority of isolates were susceptible to the fluoroquinolones. The MAR index ranged from 0.12 to 0.59, with majority of isolates indicating high-risk contamination originating from humans or animals where antibiotics are often used. Plasmids were detected in 21 isolates, with 14 of the isolates displaying multiple plasmid profiles. Single and multiple class A family Tet determinants were observed in 27% and 48.7% of isolates, respectively, with Tet A being the most prevalent Tet determinant type. Class 1 integron and related structures were amplified and carried different combinations of the antibiotic resistance gene cassettes ant(3'')Ia, aac(6')Ia, dhfr1, oxa2a and/or pse1. Class 2 integrons were also amplified, but the

  17. Effects of temperature on biochemical reactions and drug resistance of virulent and avirulent Aeromonas salmonicida

    Science.gov (United States)

    Hahnel, G.B.; Gould, R.W.

    1982-01-01

    Incubation temperatures of 11°, 18° and 28° did not substantially affect biochemical reactions of either virulent or avirulent forms of Aeromonas salmonicida subspecies salmonicida. The only change observed, amygdalin fermentation, was positive at 11° and 18° but negative at 28°C. Several isolates utilized sucrose, a characteristic not normally recognized for A. salmonicida subspecies salmonicida.Antimicrobial susceptibility screening indicated resistance to novobiocin increased at the higher incubation temperatures. Standardized drug sensitivity testing procedures and precise zone diameter interpretive standards for bacterial fish pathogens are needed.

  18. Diabetic Foot Due to Aeromonas Hydrophila and Pseudomonas Oryzihabitans: A Case Report

    Directory of Open Access Journals (Sweden)

    Aysel Talan

    2014-09-01

    Full Text Available Foot infections are the most common cause of amputations in diabetic patients. The main predisposing reasons for the development of foot ulcers and subsequent infection in diabetic patients are sensory neuropathy, vascular insufficiency and immune system abnormalities due to hyperglycemia. Limb-threatening infections are often polymicrobial. Staphylococcus aureus, group B streptococci, enterococci and facultative gram-negative bacilli are the most common pathogens. Here, we present two cases of diabetic foot infected by extremely rare microorganisms: Aeromonas hydrophila, and Pseudomonas (Flavimonas oryzihabitans. Turk Jem 2014; 18: 100-102

  19. Structure of the O-specific polysaccharide from the lipopolysaccharide of Aeromonas sobria strain Pt312.

    Science.gov (United States)

    Turska-Szewczuk, Anna; Pietras, Hubert; Duda, Katarzyna A; Kozińska, Alicja; Pękala, Agnieszka; Holst, Otto

    2015-02-11

    The O-specific polysaccharide (OPS) obtained by mild-acid degradation of the lipopolysaccharide from Aeromonas sobria strain Pt312 was studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including 2D 1H,1H COSY, TOCSY, NOESY, 1H-detected 1H,13C HSQC, and HMBC experiments. The sequence of the sugar residues was determined using 1H,1H NOESY and 1H,13C HMBC experiments. It was found that the OPS was built up of disaccharide repeating units composed of GlcpNAc and non-stoichiometrically O-acetylated Rhap residues, and had the structure.

  20. Rapid biochemical screening for Salmonella, Shigella, Yersinia, and Aeromonas isolates from stool specimens.

    Science.gov (United States)

    De Ryck, R; Struelens, M J; Serruys, E

    1994-06-01

    Four screens for the rapid (4 to 6 h) biochemical detection of pathogens from enteric isolation media are described. The Salmonella screen consisted of Kligler iron agar (KIA), motility-indole-urea-tryptophan-deamination semisolid medium (MIU-TDA), and the o-nitrophenyl-beta-D-galactopyranoside (ONPG) test; the Shigella screen consisted of KIA, MIU-TDA, the ONPG test, and the lysine decarboxylation-indole test; the Yersinia screen consisted of a rhamnose broth; the Aeromonas screen consisted of a xylose agar plate. When tested on 2,102 fresh isolates and 71 stock strains, the screens correctly detected 212 enteric pathogens (sensitivity, 100%), with a specificity of 98.1%.

  1. Expression, purification, crystallization and preliminary X-ray analysis of Aeromonas hydrophilia metallo-[beta]-lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, N.; Toney, J.H.; Fitzgerald, P.M.D. (Merck)

    2010-07-20

    The CphA metallo-{beta}-lactamase from Aeromonas hydrophilia has been expressed, purified and crystallized by the hanging-drop vapor-diffusion method using ammonium sulfate as the precipitant. The crystals exhibit orthorhombic symmetry (P2{sub 1}2{sub 1}2), with unit-cell parameters a = 40.75, b = 42.05, c = 128.88 {angstrom}. There is one monomer in the asymmetric unit and the solvent content is estimated to be 44% by volume. A data set extending to 1.8 {angstrom} has been measured.

  2. Taxonomía y epidemiología del género aeromonas

    OpenAIRE

    Alperi Vega, Anabel

    2009-01-01

    Durante la presente tesis doctoral se ha establecido la presencia de variabilidad interoperónica en el gen ARNr 16S de Aeromonas y observado que ésta afectaba a la taxonomía del género, limitando la identificación de A. caviae, A. media y A. veronii. La secuenciación del gen rpoD permitió identificar las cepas con variabilidad interoperónica a nivel de especie y reconocer 5 nuevas especies del género: A. fluvialis, A. taiwanensis, A. sanarelii, A. piscicola y A. rivuli. En colaboración con d...

  3. Aeromonas species in stabilization ponds in the arid region of Marrakesh, Morocco, and relation to fecal-pollution and climatic factors.

    Science.gov (United States)

    Boussaid, A; Baleux, B; Hassani, L; Lesne, J

    1991-12-01

    During the period 12 July 1985 to 23 December 1987, water samples were collected in two-week intervals for estimates ofAeromonas species in a waste treatment system located in the arid region of Marrakech, Morocco. Fecal coliforms, temperature, and chemical oxygen demand were measured simultaneously withAeromonas species densities. Statistical methods were utilized to analyze the significance of average differences and temporal patterns ofAeromonas species numbers.Removal ofAeromonas in the whole system did not exceed 1.14 log.Aeromonas densities showed significantly higher resistance to the treatment process when compared with fecal coliforms; however, abundance of the two groups presented a similar seasonal change. The highest numbers occurred during the cold months, while the lowest appeared in the warm months. Statistical time-series analyses of the densities data showed the seasonal and cyclic distribution ofAeromonas in this treatment plant.These temporal changes were simultaneously observed in all the stations investigated and were negatively correlated with water temperature values.Aeromonas populations were dominated byA. caviae andA. hydrophila in the inlet samples. These two species were rapidly eliminated in the treatment plant. The temporal distribution ofA. caviae was similar to the change in densities ofAeromonas and fecal coliforms. The seasonal fluctuations of abundance ofAeromonas were probably related to this species, which dominated in the winter samples but dropped during the summer. Meanwhile,A. sobria dominated all the final effluent samples. This greater survival ofA. sobria and its known pathogenicity may limit the re-use of treated water for irrigation of fodder plants.

  4. Characterization of Virulence Properties of Aeromonas veronii Isolated from Diseased Gibel Carp (Carassius gibelio)

    Science.gov (United States)

    Sun, Jingjing; Zhang, Xiaojun; Gao, Xiaojian; Jiang, Qun; Wen, Yi; Lin, Li

    2016-01-01

    Aeromonas veronii is a kind of opportunistic pathogen to fish and humans, significantly impending aquaculture production. Recently, we isolated two A. veronii strains, named GYC1 and GYC2, from diseased Gibel carp (Carassius gibelio) in China. Based on gyrB (DNA gyrase B subunit) genes of GYC1 and GYC2, the constructed phylogenetic tree showed that the two strains were clustered with A. veronii. Sixteen virulence genes related to the pathogenicity of Aeromonas spp. were subjected to PCR assay. The genes of ompAI, ompAII, lafA, act, aer, fla, gcaT and acg were detected in the two strains, while genes of hly, ahp, lip, ast and alt were not detected. Additionally, genes eprCAI, ela and exu were only detected in the strain GYC1. Furthermore, the results of extracellular enzyme analysis revealed that the two isolates can produce hemolysin, caseinase, esterase, amylase and lecithinase, which were closely related to the pathogenicity of the two strains. However, the results showed that there was no gelatinase activity in either strain. According to the antibiotic resistant assay, the two strains were sensitive to cephalosporins and aminoglycosides, while they were resistant to penicillins and quinolones. Through this study, the virulence characteristics, including virulence genes and extracellular enzymes, the pathogenicity of A. veronii was clarified, enhancing the understanding about this pathogenic bacterium and providing the theoretical basis in disease control. PMID:27043558

  5. sugE: A gene involved in tributyltin (TBT) resistance of Aeromonas molluscorum Av27.

    Science.gov (United States)

    Cruz, Andreia; Micaelo, Nuno; Félix, Vitor; Song, Jun-Young; Kitamura, Shin-Ichi; Suzuki, Satoru; Mendo, Sónia

    2013-01-01

    The mechanism of bacterial resistance to tributyltin (TBT) is still unclear. The results herein presented contribute to clarify that mechanism in the TBT-resistant bacterium Aeromonas molluscorum Av27. We have identified and cloned a new gene that is involved in TBT resistance in this strain. The gene is highly homologous (84%) to the Aeromonas hydrophila-sugE gene belonging to the small multidrug resistance gene family (SMR), which includes genes involved in the transport of lipophilic drugs. In Av27, expression of the Av27-sugE was observed at the early logarithmic growth phase in the presence of a high TBT concentration (500 μM), thus suggesting the contribution of this gene for TBT resistance. E. coli cells transformed with Av27-sugE become resistant to ethidium bromide (EtBr), chloramphenicol (CP) and tetracycline (TE), besides TBT. According to the Moriguchi logP (miLogP) values, EtBr, CP and TE have similar properties and are substrates for the sugE-efflux system. Despite the different miLogP of TBT, E. coli cells transformed with Av27-sugE become resistant to this compound. So it seems that TBT is also a substrate for the SugE protein. The modelling studies performed also support this hypothesis. The data herein presented clearly indicate that sugE is involved in TBT resistance of this bacterium.

  6. In Vitro Phytochemical And Antibacterial Activity Test On Temu Putih Extract Curcuma Zedoaria Against Aeromonas Hydrophila

    Directory of Open Access Journals (Sweden)

    Dimas Galang Prakosa

    2015-08-01

    Full Text Available Aeromonas hydrophila bacterium is one of the bacteria which frequently attack fresh water aquaculture and cause the farmer experience terrible loss. In order to cope with the diseases caused by A. hydrophila bacteria the usage of natural antibacteria was more recommended as it does not give negative effects to the environment. One natural antibacteria which can be used against A. hydrophila is from the white turmeric extract Curcuma zedoaria. The aim of this study is to know the active compound content in white turmeric Curcuma zedoaria to determine the most effective solvent and the effective maceration duration to extract Curcuma zedoaria as antibacteria against Aeromonas hydrophila using disc diffusion method. The study used descriptive and experimental method with treatments to 3 different solvents ethanol ethyl acetate and chloroform and 3 repetitions. The data acquired from the results of the study were then analyzed descriptively. Results showed that Curcuma zedoaria extract from the phytochemical test contained saponins alkaloid and flavonoid. The best solvent was ethyl acetate with maceration for 2x24 hours and inhibition area width 11.34 mm.

  7. Polyphasic characterization of Aeromonas salmonicida isolates recovered from salmonid and non-salmonid fish

    Science.gov (United States)

    Diamanka, A.; Loch, T.P.; Cipriano, R.C.; Faisal, M.

    2013-01-01

    Michigan's fisheries rely primarily upon the hatchery propagation of salmonid fish for release in public waters. One limitation on the success of these efforts is the presence of bacterial pathogens, including Aeromonas salmonicida, the causative agent of furunculosis. This study was undertaken to determine the prevalence of A. salmonicida in Michigan fish, as well as to determine whether biochemical or gene sequence variability exists among Michigan isolates. A total of 2202 wild, feral and hatchery-propagated fish from Michigan were examined for the presence of A. salmonicida. The examined fish included Chinook salmon, Oncorhynchus tshawytscha (Walbaum), coho salmon, O. kisutcha (Walbaum), steelhead trout, O. mykiss (Walbaum), Atlantic salmon, Salmo salar L., brook trout, Salvelinus fontinalis (Mitchill), and yellow perch, Perca flavescens (Mitchill). Among these, 234 fish yielded a brown pigment-producing bacterium that was presumptively identified as A. salmonicida. Further phenotypic and phylogenetic analyses identified representative isolates as Aeromonas salmonicida subsp. salmonicida and revealed some genetic and biochemical variability. Logistic regression analyses showed that infection prevalence varied according to fish species/strain, year and gender, whereby Chinook salmon and females had the highest infection prevalence. Moreover, this pathogen was found in six fish species from eight sites, demonstrating its widespread nature within Michigan.

  8. Characterization of Virulence Properties of Aeromonas veronii Isolated from Diseased Gibel Carp (Carassius gibelio).

    Science.gov (United States)

    Sun, Jingjing; Zhang, Xiaojun; Gao, Xiaojian; Jiang, Qun; Wen, Yi; Lin, Li

    2016-04-01

    Aeromonas veronii is a kind of opportunistic pathogen to fish and humans, significantly impending aquaculture production. Recently, we isolated two A. veronii strains, named GYC1 and GYC2, from diseased Gibel carp (Carassius gibelio) in China. Based on gyrB (DNA gyrase B subunit) genes of GYC1 and GYC2, the constructed phylogenetic tree showed that the two strains were clustered with A. veronii. Sixteen virulence genes related to the pathogenicity of Aeromonas spp. were subjected to PCR assay. The genes of ompAI, ompAII, lafA, act, aer, fla, gcaT and acg were detected in the two strains, while genes of hly, ahp, lip, ast and alt were not detected. Additionally, genes eprCAI, ela and exu were only detected in the strain GYC1. Furthermore, the results of extracellular enzyme analysis revealed that the two isolates can produce hemolysin, caseinase, esterase, amylase and lecithinase, which were closely related to the pathogenicity of the two strains. However, the results showed that there was no gelatinase activity in either strain. According to the antibiotic resistant assay, the two strains were sensitive to cephalosporins and aminoglycosides, while they were resistant to penicillins and quinolones. Through this study, the virulence characteristics, including virulence genes and extracellular enzymes, the pathogenicity of A. veronii was clarified, enhancing the understanding about this pathogenic bacterium and providing the theoretical basis in disease control.

  9. Characterization and Expression of Outer Membrane Protein AI Gene of Aeromonas veronii

    Institute of Scientific and Technical Information of China (English)

    Wang Hai-juan; Wang Li

    2015-01-01

    The outer membrane protein, ompA, ofAeromonas veronii has a role in the virulence of the organism and is a potential candidate for vaccine development. In this study, ompAⅠofAeromonas veronii strain WA106 was cloned and sequenced, then, it was expressed inEscherichia coli BL21. The nucleotide sequence of ompAⅠgene was 1 023 base pairs (GenBank Accession NO.KC748024), which showed 100% homology with that ofA. veronii (NO.AB290200.1). This predicted protein was composed of 340 amino acid residues. Its molecular weight was 35.78 ku and isoelectric point was 5.18. The protein was a hydrophilic protein containing alpha helix and random coil with percentage of 35.0% and 49.7%, respectively. The tertiary structure, quaternary structure prediction showed that ompAⅠprotein contained two peptide chains. SDS-PAGE showed that the actual value of the fusion protein was consistent with the expected result. It will facilitate further study of the role of ompAⅠprotein.

  10. Distribution of 13 virulence genes among clinical and environmental Aeromonas spp. in Western Australia.

    Science.gov (United States)

    Aravena-Román, M; Inglis, T J J; Riley, T V; Chang, B J

    2014-11-01

    We evaluated the pathogenic potential of 98 clinical and 31 environmental Aeromonas isolates by detecting the presence of 13 virulence genes using a polymerase chain reaction (PCR)-based method. The majority (96 %) of the strains contained at least one of the virulence genes. The overall distribution was aerA/haem (77 %), alt (53 %), lafA (51 %), ast (39 %), flaA (32 %), aspA (29 %), vasH (26 %), ascV (16 %) and aexT (13 %). No amplification products were detected for the genes encoding a bundle-forming pilus (BfpA and BfpG) or a Shiga-like toxin (stx-1 and stx-2). Five or more virulence genes were detected in 42 % of environmental and 24 % of clinical isolates. Among the major species, 48 % of A. hydrophila and 42 % of A. dhakensis isolates harboured five or more virulence genes compared with 19 % in A. veronii bv. sobria and none in A. caviae isolates. Our results suggest that, in Western Australia, strains of A. dhakensis and A. hydrophila are potentially more virulent than those of A. veronii bv. sobria and A. caviae, although the pathogenic potential of Aeromonas spp. is probably strain- rather than species-dependent.

  11. Antibiotic resistance profiling and phenotyping of Aeromonas species isolated from aquatic sources

    Directory of Open Access Journals (Sweden)

    Olumide A. Odeyemi

    2017-01-01

    Full Text Available This study aimed to investigate antibiotics resistance pattern and phenotyping of Aeromonas species isolated from different aquatic sources in Melaka, Malaysia. A total of 53 Aeromonas species were isolated from the following sources: sediment (n = 13, bivalve (n = 10, sea cucumber (n = 16 and sea water (n = 14 and resistance to 12 antibiotics – Tetracycline (30 μg, Kanamycin (30 μg, Oxytetracycline (30 μg, Ampicillin (10 μg, Streptomycin (10 μg, Gentamicin (10 μg, Sulphamethoxazole (25 μg, Nalixidic acid (30 μg, Trimethoprim (1.25 μg, Novobiocin (5 μg, Penicilin (10 μg and Chloramphenicol (10 μg was tested. The results obtained from this study reveal multi drug resistance pattern among the isolates. All the isolates were completely resistant to Ampicillin, Novobiocin, Sulphamethoxazole and Trimethoprim, respectively but susceptible to Tetracycline (100%, Kanamycin (5.7%, Gentamicin (5.7% and Oxytetracycline (24.5%. Antibiotics phenotyping of the bacteria revealed 21 different phenotypes among the isolates.

  12. Bioremediation and Detoxification of Synthetic Wastewater Containing Triarylmethane Dyes by Aeromonas hydrophila Isolated from Industrial Effluent

    Directory of Open Access Journals (Sweden)

    Chimezie Jason Ogugbue

    2011-01-01

    Full Text Available Economical and bio-friendly approaches are needed to remediate dye-contaminated wastewater from various industries. In this study, a novel bacterial strain capable of decolorizing triarylmethane dyes was isolated from a textile wastewater treatment plant in Greece. The bacterial isolate was identified as Aeromonas hydrophila and was shown to decolorize three triarylmethane dyes tested within 24 h with color removal in the range of 72% to 96%. Decolorization efficiency of the bacterium was a function of operational parameters (aeration, dye concentration, temperature, and pH and the optimal operational conditions obtained for decolorization of the dyes were: pH 7-8, 35∘C and culture agitation. Effective color removal within 24 h was obtained at a maximum dye concentration of 50 mg/L. Dye decolorization was monitored using a scanning UV/visible spectrophotometer which indicated that decolorization was due to the degradation of dyes into non-colored intermediates. Phytotoxicity studies carried out using Triticum aestivum, Hordeum vulgare, and Lens esculenta revealed the triarylmethane dyes exerted toxic effects on plant growth parameters monitored. However, significant reduction in toxicity was obtained with the decolorized dye metabolites thus, indicating the detoxification of the dyes following degradation by Aeromonas hydrophila.

  13. Aeromonas punctata derived depolymerase that disrupts the integrity of Klebsiella pneumoniae capsule: optimization of depolymerase production.

    Science.gov (United States)

    Bansal, Shruti; Soni, Sanjeev Kumar; Harjai, Kusum; Chhibber, Sanjay

    2014-07-01

    Formation of dense, highly hydrated biofilm structures pose a risk for public and environmental health. Extracellular polymeric substances encompassing biofilms offer 1000-fold greater resistance as compared to the planktonic cells. Using enzymes as anti-biofouling agents, will improve penetration of antimicrobials and increase susceptibility of biofilms to components of immune system. The challenge of using enzymes derived from unrelated bacteria for the degradation of capsular matrix of Klebsiella pneumoniae has not been dealt in the past. Thus, statistical optimization was done to enhance depolymerase production by Aeromonas punctata, directed against the exopolysaccharide matrix of Klebsiella pneumoniae B5055, capable of substituting the available phage borne depolymerase enzyme. Optimization via central composite design (CCD) resulted in 16-fold enhancement in depolymerase yield (166.65 µmoles ml(-1)  min(-1) ) over unoptimized medium. Out of the 19 variables, media composition giving maximum expression levels of the enzyme consisted of 1 mg ml(-1) galactose and ammonium chloride, 1.5 mg ml(-1) each of capsular polysaccharide (CPS) and magnesium sulfate. Tryptic peptide analysis of the purified 29 kDa band by Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) showed a high homology with a protein of unknown function from Aeromonas cavaie Ae398. Further improvements in the enzyme can lead to its successful development as prophylactic and/or a therapeutic agent.

  14. The Aeromonas salmonicida Lipopolysaccharide Core from Different Subspecies: The Unusual subsp. pectinolytica.

    Science.gov (United States)

    Merino, Susana; Tomás, Juan M

    2016-01-01

    Initial hydridization tests using Aeromonas salmonicida typical and atypical strains showed the possibility of different lipopolysaccharide (LPS) outer cores among these strains. By chemical structural analysis, LPS-core SDS-PAGE gel migration, and functional and comparative genomics we demonstrated that typical A. salmonicida (subsp. salmonicida) strains and atypical subsp. masoucida and probably smithia strains showed the same LPS outer core. A. salmonicida subsp. achromogenes strains show a similar LPS outer core but lack one of the most external residues (a galactose linked α1-6 to heptose), not affecting the O-antigen LPS linkage. A. salmonicida subsp. pectinolytica strains show a rather changed LPS outer core, which is identical to the LPS outer core from the majority of the A. hydrophila strains studied by genomic analyses. The LPS inner core in all tested A. salmonicida strains, typical and atypical, is well-conserved. Furthermore, the LPS inner core seems to be conserved in all the Aeromonas (psychrophilic or mesophilic) strains studied by genomic analyses.

  15. Antibiotic resistance profiling and phenotyping of Aeromonas species isolated from aquatic sources.

    Science.gov (United States)

    Odeyemi, Olumide A; Ahmad, Asmat

    2017-01-01

    This study aimed to investigate antibiotics resistance pattern and phenotyping of Aeromonas species isolated from different aquatic sources in Melaka, Malaysia. A total of 53 Aeromonas species were isolated from the following sources: sediment (n = 13), bivalve (n = 10), sea cucumber (n = 16) and sea water (n = 14) and resistance to 12 antibiotics - Tetracycline (30 μg), Kanamycin (30 μg), Oxytetracycline (30 μg), Ampicillin (10 μg), Streptomycin (10 μg), Gentamicin (10 μg), Sulphamethoxazole (25 μg), Nalixidic acid (30 μg), Trimethoprim (1.25 μg), Novobiocin (5 μg), Penicilin (10 μg) and Chloramphenicol (10 μg) was tested. The results obtained from this study reveal multi drug resistance pattern among the isolates. All the isolates were completely resistant to Ampicillin, Novobiocin, Sulphamethoxazole and Trimethoprim, respectively but susceptible to Tetracycline (100%), Kanamycin (5.7%), Gentamicin (5.7%) and Oxytetracycline (24.5%). Antibiotics phenotyping of the bacteria revealed 21 different phenotypes among the isolates.

  16. Polymerase chain reaction (PCR)-based typing analysis of atypical isolates of the fish pathogen Aeromonas salmonicida

    DEFF Research Database (Denmark)

    Høie, S.; Dalsgaard, Inger; Aase, I.L.;

    1999-01-01

    Two hundred and five isolates of atypical Aeromonas salmonicida, recovered from a wide range of hosts and countries were characterized by polymerase chain reaction (PCR) targeting four genes. The chosen genes were those encoding the extracellular A-layer protein (AP), the serine protease (Sprot...

  17. Potential role of specific antibodies in vaccine-induced protection against Aeromonas salmonicida subsp. salmonicida in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Villumsen, Kasper Rømer; Dalsgaard, Inger; Raida, Martin Kristian

    2012-01-01

    Furunculosis caused by infection with Aeromonas salmonicida subsp. salmonicida has now been a known threat to aquaculture for more than a century. Efficient prophylactic precautions against this disease are essential for continued growth of salmonid fish aquaculture. Ever since the introduction...

  18. Chicken-type lysozyme in channel catfish: Expression analysis, lysozyme activity and efficacy as immunostimulant against Aeromonas hydrophila infection

    Science.gov (United States)

    To understand whether chicken-type lysozyme (Lys-c) in channel catfish was induced by infection of Aeromonas hydrophila, the transcriptional levels of Lys-c in skin, gut, liver, spleen, posterior kidney, and blood cells in healthy channel catfish was compared to that in channel catfish infected with...

  19. Vaccination of channel catfish with extracellular products of Aeromonas hydrophila provides protection against infection by the pathogen

    Science.gov (United States)

    Aeromonas hydrophila, a Gram-negative bacterium, is one of the economically-important pathogens in modern aquaculture. Among various traits, extracellular products (ECP) secreted by the bacterium are considered to be essential factors for virulence. Whether vaccination with the ECP could produce imm...

  20. Inventarisatie van Aeromonas spp. in het drinkwater van 21 pompstations in de periode september 1985-december 1986 (deel II)

    NARCIS (Netherlands)

    Versteegh JFM; During M; Havelaar AH

    1987-01-01

    In de periode september 1985-december 1986 is in samenwerking met een aantal drinkwaterbedrijven een inventariserend onderzoek uitgevoerd naar het voorkomen van Aeromonas-bacterien in verschillende typen drinkwater geproduceerd op 21 drinkwaterpompstations. Nadat in de loop van het onderzoek duidel

  1. Comparative evaluation of infection methods and environmental factors on challenge success: Aeromonas salmonicida infection in vaccinated rainbow trout

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Skov, Jakob; Jaafar, Rzgar M.;

    2015-01-01

    When testing vaccine-induced protection an effective and reliable challenge method is a basic requirement and we here present a comparative study on different challenge methods used for infection of rainbow trout Oncorhynchus mykiss with Aeromonas salmonicida, a bacterial pathogen eliciting...

  2. Degradation of chitin and chitosan by a recombinant chitinase derived from a virulent Aeromonas hydrophila isolated from diseased channel catfish

    Science.gov (United States)

    A chitinase was identified in extracellular products of a virulent Aeromonas hydrophila isolated from diseased channel catfish (Ictalurus punctatus). Bioactive recombinant chitinase (rChi-Ah) was produced in Escherichia coli. Purified rChi-Ah had optimal activity at temperature of 42°C and pH 6.5. T...

  3. Antibiogram, adhesive characteristics, and incidence of class 1 integron in Aeromonas species isolated from two South African rivers.

    Science.gov (United States)

    Igbinosa, Isoken H; Chigor, Vincent N; Igbinosa, Etinosa O; Obi, Lawrence C; Okoh, Anthony I

    2013-01-01

    Aeromonas species are well distributed in freshwater environments, and their natural susceptibility to antimicrobials renders them interesting candidates for the survey of antimicrobial resistance in freshwater milieu. Water samples were collected from Kat and Tyume rivers in the Eastern Cape province of South Africa, and a total of 45 isolates identified as Aeromonas species were recovered from the two rivers. All Aeromonas isolates were resistant to oxacillin, penicillin, clindamycin, cephalothin, vancomycin, and rifamycin, while appreciable susceptibilities (89.3 : 94.1%, 82.1 : 94.1%, 85.7 : 88.2%, and 92.9 : 88.2%) were observed against ciprofloxacin, chloramphenicol, nitrofurantoin, and gentamicin from Kat and Tyume rivers, respectively. Multiple antibiotic resistance (MAR) indices ranged from 0.016 to 0.044 for the two rivers. Class 1 integron was detected in about 20% of the isolates, and all the isolates except one showed ability to produce biofilm in vitro as weak producers (53.33%), moderate producers (15.56%), and strong producers (28.9%). This investigation provides a baseline data on antibiotic resistance as well as the adhesive characteristics of Aeromonas isolates from Tyume and Kat rivers in the Eastern Cape province of South Africa.

  4. DISTRIBUTION OF SIX VIRULENCE FACTORS IN AEROMONAS SPECIES ISOLATED FROM US DRINKING WATER UTILITIES: A PCR IDENTIFICATION

    Science.gov (United States)

    Surveys of finished drinking water conducted by the U.S. EPA during 2000-2001, revealed 7 out of 16 water utilities encompassing four states, were contaminated with Aeromonas species. A Polymerase Chain reaction (PCR) based genetic characterization determined the presence of six...

  5. Inventarisatie van Aeromonas spp. in het drinkwater van 21 pompstations in de periode september 1985-december 1986 (deel I)

    NARCIS (Netherlands)

    Versteegh JFM; During M; Havelaar AH

    1987-01-01

    In de periode september 1985-december 1986 is in samenwerking met een aantal drinkwaterbedrijven een inventariserend onderzoek uitgevoerd naar het voorkomen van Aeromonas-bacterien in verschillende typen drinkwater geproduceerd op 21 drinkwaterpompstations. Nadat in de loop van het onderzoek duidel

  6. Antibiogram, Adhesive Characteristics, and Incidence of Class 1 Integron in Aeromonas Species Isolated from Two South African Rivers

    Directory of Open Access Journals (Sweden)

    Isoken H. Igbinosa

    2013-01-01

    Full Text Available Aeromonas species are well distributed in freshwater environments, and their natural susceptibility to antimicrobials renders them interesting candidates for the survey of antimicrobial resistance in freshwater milieu. Water samples were collected from Kat and Tyume rivers in the Eastern Cape province of South Africa, and a total of 45 isolates identified as Aeromonas species were recovered from the two rivers. All Aeromonas isolates were resistant to oxacillin, penicillin, clindamycin, cephalothin, vancomycin, and rifamycin, while appreciable susceptibilities (89.3 : 94.1%, 82.1 : 94.1%, 85.7 : 88.2%, and 92.9 : 88.2% were observed against ciprofloxacin, chloramphenicol, nitrofurantoin, and gentamicin from Kat and Tyume rivers, respectively. Multiple antibiotic resistance (MAR indices ranged from 0.016 to 0.044 for the two rivers. Class 1 integron was detected in about 20% of the isolates, and all the isolates except one showed ability to produce biofilm in vitro as weak producers (53.33%, moderate producers (15.56%, and strong producers (28.9%. This investigation provides a baseline data on antibiotic resistance as well as the adhesive characteristics of Aeromonas isolates from Tyume and Kat rivers in the Eastern Cape province of South Africa.

  7. Draft genome sequence of Pseudomonas mosselii Gil3, isolated from catfish and antagonistic against hypervirulent Aeromonas hydrophila

    Science.gov (United States)

    Pseudomonas mosselii Gil3 was isolated from a catfish that survived from lethal challenge with hypervirulent Aeromonas hydrophila (vAh). When assayed in vitro, the bacterium showed antagonism against vAh. Sequence analysis revealed that the genome of P. mosselii Gil3 encodes numerous aromatic metabo...

  8. Aeromonas species isolated from PINTADO fish (Pseudoplatystoma sp: virulence factors and drug susceptibility

    Directory of Open Access Journals (Sweden)

    Vera Lúcia Mores Rall

    1998-09-01

    Full Text Available Aeromonas has been described as an emergent foodborne pathogen of increasing importance. In this study, we report that 48% of 50 Pintado fish samples collected at the retail market of São Paulo city were positive for Aeromonas sp, as detected by the direct plating method. When the presence/absence method was used, the positivity was 42%. A. caviae was the most frequent species, followed by A. hydrophila and A. sobria. Production of cytotoxic enterotoxin, observed in suckling mouse assay, was detected in 67% of A. sobria strains, in 60% of A. hydrophila strains and in 40% of A. caviae strains. In vitro tests, performed with HEp-2 cells, showed that 88% of A. hydrophila, 27% of A. sobria and 13% of A. caviae strains were positive for this toxin. The in vivo production of cytotonic enterotoxin, tested after heating the filtrates at 56ºC for 20 minutes, was detected in 17% of A. sobria, in 10% of A. caviae and in none of A. hydrophila strains in vivo. All analyzed strains did not alter HEp-2 cells. 20% and 16% of A. sobria and A. caviae isolates, respectively, presented capacity to adhere to HEp-2 cells. In counterpart, invasion of HEp-2 cells was not observed in any isolate. The Aeromonas isolates were sensitive to the majority of the antimicrobiol agents tested.Bactérias do gênero Aeromonas têm sido descritas como patógenos emergentes de importância crescente em alimentos. Neste estudo, relatamos que 48% das amostras de peixe "Pintado" coletado no comércio de São Paulo, foram positivas para Aeromonas sp quando isoladas pelo método de plaqueamento direto. Quando o método Presença/Ausência foi utilizado, a porcentagem de positividade foi de 42%. A. caviae foi a espécie mais freqüente, seguida por A. hydrophila e A. sobria. Produção de enterotoxina citotóxica, determinada em camundongos recém-nascidos, foi observada em 67% das cepas de A. sobria, em 60% das de A. hydrophila e em 40% das de A. caviae. No teste in vitro em c

  9. The immunocross-reaction between pathogenic Aeromonas hydrophila isolated from Siberian sturgeon Acipenser baerii and other three Aeromonas strains%西伯利亚鲟嗜水气单胞菌与其它3株气单胞菌间的免疫交叉反应

    Institute of Scientific and Technical Information of China (English)

    姜有声; 杨倩; 杨先乐; 吕利群; 邱军强

    2012-01-01

    The immunological characteristics of four Aeromonas strains like pathogenic bacteria strain Xl(Aeromonas hydrophlia) isolated from Siberian sturgeon (Acipenser baerii) suffering with bacterial septicaemia, pathogenic bacteria strain XL2-T strain (Aeromonas caviae ) isolated from the sturgeon septicemia, pathogenic strain Wl (Aeromonas sobria) and non-pathogenic M3 strain (Aeromonas hydrophlia) , were detected through the cross-reactions between four Aeromonas strains and antiserums by indirect immunofluoresence assay. The results showed that the pathogenic XI strain, XL2 -T strain and Wl strain had strong cross reactions, and weak cross reactions were found on non-pathogenic M3 strain with other three pathogenic strains.%采用间接免疫荧光技术分析了西伯利亚鲟细菌性败血症致病菌嗜水气单胞菌(Aeromonas hydrophlia)X1菌株、豚鼠气单胞菌(Aeromonas caviae)XL2-T菌株、致病性温和气单胞菌(Aeromonas sobria)W1菌株与无致病性嗜水气单胞菌(Aeromonas hydrophlia)M3菌株等水产养殖主要病原菌与抗血清之间的免疫交叉反应.结果显示具有致病性的同属菌株X1菌株、XL2-T菌株、W1菌株交叉反应程度较大,说明这3株菌表面存在较多相同抗原决定簇.而无致病性菌株M3与其他3株致病性菌株免疫交叉反应程度较小.

  10. Molecular characterization of antibiotic resistance in Pseudomonas and Aeromonas isolates from catfish of the Mekong Delta, Vietnam.

    Science.gov (United States)

    Nguyen, Hoang Nam Kha; Van, Thi Thu Hao; Nguyen, Huu Thinh; Smooker, Peter M; Shimeta, Jeff; Coloe, Peter J

    2014-07-16

    A collection of 116 motile Pseudomonas spp. and 92 Aeromonas spp. isolated from 15 Vietnamese intensive catfish farms was analyzed to examine the molecular antibiotic resistance characteristics and the transferability of resistance markers within and between species. High levels of resistance to ampicillin, trimethoprim/sulfamethoxazole, nalidixic acid, chloramphenicol, and nitrofurantoin were observed. The percentage of multiple drug resistance of Pseudomonas spp. and Aeromonas spp. isolates was 96.6% and 61.9%, respectively. The multiple antibiotic resistance (MAR) index mean values of 0.457 and 0.293 of Pseudomonas and Aeromonas isolates, respectively, indicated that these isolates were exposed to high risk sources of contamination where antibiotics were commonly used. Approximately 33% of Pseudomonas spp. and 28% of Aeromonas spp. isolates from catfish contained class 1 integrons, but no class 2 integrons were detected. Several common resistance genes including aadA, dfrA and catB were harbored in class 1 integrons. Large plasmids (>55 kb) were frequently detected in 50% and 71.4% of the plasmids extracted from Pseudomonas and Aeromonas isolates, respectively. Conjugation and transformation experiments demonstrated the successful transfer of all or part of the resistance phenotypes of catfish isolates to the recipient strains, including laboratory strains and strains isolated from this study. These results highlight the likely role of catfish bacteria as a reservoir of antibiotic resistant, Gram-negative bacteria harboring a pool of mobile genetic elements that can readily be transferred intra- and interspecies. To our knowledge, this is the first report on molecular characterization of antibiotic resistance of bacteria isolated from catfish in Vietnam.

  11. Distribution and phenotypic and genotypic detection of a metallo-β-lactamase, CphA, among bacteraemic Aeromonas isolates.

    Science.gov (United States)

    Wu, Chi-Jung; Chen, Po-Lin; Wu, Jiunn-Jong; Yan, Jing-Jou; Lee, Chin-Chi; Lee, Hsin-Chun; Lee, Nan-Yao; Chang, Chia-Ming; Lin, Yu-Tzu; Chiu, Yen-Cheng; Ko, Wen-Chien

    2012-05-01

    The objectives of the study were to investigate the distribution of cphA-related genes (cphA) encoding a CphA metallo-β-lactamase (MBL) among 51 consecutive Aeromonas blood isolates and to compare different phenotypic methods for detecting CphA. The presence of cphA was detected by PCR. Four phenotypic methods, the imipenem-EDTA combined disc test, imipenem-EDTA MBL Etest, agar dilution test and modified Hodge test (MHT), were used to detect imipenem susceptibility and MBL production. The results showed that 35 (69%) blood isolates had cphA. All (100%) of 16 Aeromonas aquariorum isolates and 12 Aeromonas veronii isolates, and 4 (80%) of 5 Aeromonas hydrophila isolates, carried cphA, but none of 15 Aeromonas caviae isolates did. With the standard inocula, irrespective of the presence or absence of cphA, all but one (50, 98%) isolates were susceptible to imipenem tested by disc diffusion, Etest and agar dilution (10(4) c.f.u. spot inocula), and did not exhibit MBL production by the imipenem-EDTA combined disc test and MBL Etest. By the agar dilution test using large inocula (10(7) c.f.u.), 34 (97%) of 35 cphA(+) isolates had imipenem MICs of ≥16 µg ml(-1), higher than the susceptible breakpoint (4 µg ml(-1)), and demonstrated positive results for the MHT, while one cphA(+) and all 17 cphA(-) isolates had imipenem MICs of ≤4 µg ml(-1). In conclusion, the distribution of cphA among aeromonads is species-specific, found in A. aquariorum, A. veronii and A. hydrophila, and the MHT may be a phenotypic screening test for CphA production.

  12. Hematologia e sinais clínicos de Piaractus mesopotamicus infectados experimentalmente com Aeromonas hydrophila = Hematology and clinical signs of Piaractus mesopotamicus experimentally infected with Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Flávio Ruas Moraes

    2009-01-01

    Full Text Available Este ensaio teve como objetivo avaliar as respostas hematológicas e a ocorrência de sinais clínico-patológicos de Piaractus mesopotamicus infectados experimentalmente por Aeromonas hydrophila. Foram utilizados 324 pacus, P. mesopotamicus, com peso de 102,84 ±27,1 g, distribuídos em 27 caixas de 300 L de capacidade, sendo 14 peixes por caixa. Os peixes foram mantidos nas caixas durante um mês, recebendo dieta balanceada, período em que se evitou qualquer tipo de manejo estressante. Passado esse período, foram infectadoscom 6 x 106 UFC de A. hydrophila, injetada via intraperitoneal. As coletas e análises de sangue foram realizadas 24h antes da infecção experimental e 24h após a infecção. Os resultados permitem concluir que a infecção por A. hydrophila em P. mesopotamicus écaracterizada por escurecimento da derme e sinais clínicos-patológicos relacionados à hemorragia, anemia normocítica-hipocrômica, redução nos níveis de proteínas, globulinasplasmáticas e eosinófilos, leucopenia, linfopenia, trombocitopenia, neutrofilia e monocitose. The purpose of this study was to evaluate the hematological response and clinical sign of Piaractus mesopotamicus infected byAeromonas hydrophila. Were used 324 pacus, P. mesopotamicus weighing 102.84 ± 27.1 g distributed in 27 water tanks with 300 L of capacity, 14 fish per tank. The fish were kept in the water tanks during one month, receiving appropriate diet. In this period was avoidedstressing management. After this period, the fish were infected with 6 × 108 cfu of A. hydrophila fish-1, injected intraperitoneally. The blood collection was carried 24h before experimental infection and 24h after its. The A. hydrophila infection in P. mesopotamicus ischaracterized by dark skin and clinical signs related to hemorrhage, hypochromic normocytic anemia, decrease on plasmatic proteins and globulins levels, leucopenia, lymphopenia, thrombocytopenia, eosinophilia, neutrophilia and monocytosis.

  13. 聚维酮碘对气单胞菌的抑菌杀菌效果研究%Research on Bacteriostatic and Bactericidal Efficacy of Povidone Iodine on Aeromonas

    Institute of Scientific and Technical Information of China (English)

    谭凤霞

    2011-01-01

    [目的]研究聚维酮碘作为一种水产养殖上常用的消毒剂对气单胞菌的抑菌杀菌效果。[方法]以气单胞菌属标准株ATCC7966和分离自患病鱼及养殖环境的气单胞菌为试验菌株,通过肉汤二倍稀释法研究聚维酮碘的抑菌杀菌作用。[结果]聚维酮碘在低浓度时能抑制气单胞菌的生长增殖,高浓度时杀灭细菌,其对Aeromonas sp. T1、Aeromonas sp. T2、Aeromonas sp. T4菌株的最小抑菌浓度为125. 00mg/L,最小杀菌浓度为4.00g/L;其对ATCC7966、Aeromonas sp. T3、Aeromonas sp. T5、Aeromonas sp. T6菌株的最小抑菌浓度为250.00 mg/L,最小杀菌浓度为8.00 g/L。[结论]为聚维酮碘的合理使用提供了一定的依据。%[Objective] The aim of this study is to investigate the bacteriostatic and bactericidal efficacy of povidone iodine as one kind of disinfectants for aquaculture on Aeromonas.[Method] With the standard strain of Aeromonas ATCC7966 and the Aeromonas strains isolated from diseased fish or aquatic environment as the tested strains,the bacteriostatic and bactericidal efficacy of povidone iodine was studied by double broth dilution method.[Result] The povidone iodine could inhibit the growth of Aeromonas strains at lower concentration,and killed Aeromonas strains at higher concentration.The minimum bacteriostatic concentration(MIC) of povidone iodine on Aeromonas sp.T1,Aeromonas sp T2 and Aeromonas sp.T4 was 125.00 mg/L,and the minimum bactericidal concentration(MBC) was 4.00 g/L.Whereas,the minimum bacteriostatic concentration(MIC) of povidone iodine on ATCC7966,Aeromonas sp.T3,Aeromonas sp T5 and Aeromonas sp.T6 was 250.00 mg/L,and the minimum bactericidal concentration(MBC) was 8.00 g/L.[Conclusion] This study provides certain basis for reasonable application of povidone iodine.

  14. 聚维酮碘对气单胞菌的抑菌杀菌效果研究%Research on Bacteriostatic and Bactericidal Efficacy of Povidone Iodine on Aeromonas

    Institute of Scientific and Technical Information of China (English)

    谭凤霞

    2011-01-01

    [Objective] The aim of this study is to investigate the bacteriostatic and bactericidal efficacy of povidone iodine as one kind of disinfectants for aquaculture on Aeromonas. [ Method] With the standard strain of Aeromonas ATCC7966 and the Aeromonas strains isolated from diseased fish or aquatic environment as the tested strains, the bacteriostatic and bactericidal efficacy of povidone iodine was studied by double broth dilution method. [Result] The povidone iodine could inhibit the growth of Aeromonas strains at lower concentration, and killed Aeromonas strains at higher concentration. The minimum bacteriostatic concentration (MIC) of povidone iodine on Aeromonas sp. T1, Aeromonas sp. T2 and Aeromonas sp. T4 was 125.00 mg/L, and the minimum bactericidal concentration (MBC) was4.00 g/L. Whereas, the minimum bacteriostatic concentration (MIC) of povidone iodine on ATCC7966, Aeromonas sp. T3, Aeromonas sp. T5 and Aeromonas sp. T6 was 250.00 mg/L, and the minimum bactericidal concentration (MBC) was 8.00 g/L. [ Conclusion] This study provides certain basis for reasonable application of povidone iodine.%[目的]研究聚维酮碘作为一种水产养殖上常用的消毒剂对气单胞菌的抑菌杀菌效果.[方法]以气单胞菌属标准株ATCC7966和分离自患病鱼及养殖环境的气单胞菌为试验菌株,通过肉汤二倍稀释法研究聚维酮碘的抑菌杀菌作用.[结果]聚维酮碘在低浓度时能抑制气单胞菌的生长增殖,高浓度时杀灭细菌,其对Aeromonas sp.T1、Aeromonas sp.T2、Aeromonas sp.T4菌株的最小抑菌浓度为125.00 mg/L,最小杀菌浓度为4.00 g/L;其对ATCC7966、Aeromonas sp.T3、Aeromonas sp.T5、Aeromonas sp.T6菌株的最小抑菌浓度为250.00mg/L,最小杀菌浓度为8.00g/L.[结论]为聚维酮碘的合理使用提供了一定的依据.

  15. Positive correlation between Aeromonas salmonicida vaccine antigen concentration and protection in vaccinated rainbow trout Oncorhynchus mykiss evaluated by a tail fin infection model

    DEFF Research Database (Denmark)

    Marana, M. H.; Skov, J.; Chettri, Jiwan Kumar;

    2016-01-01

    Rainbow trout, Oncorhynchus mykiss (Walbaum), are able to raise a protective immune response against Aeromonas salmonicida subsp. salmonicida (AS) following injection vaccination with commercial vaccines containing formalin-killed bacteria, but the protection is often suboptimal under Danish...... mariculture conditions. We elucidated whether protection can be improved by increasing the concentration of antigen (formalin-killed bacteria) in the vaccine. Rainbow trout juveniles were vaccinated by intraperitoneal (i.p.) injection with a bacterin of Aeromonas salmonicida subsp. salmonicida strain 090710...

  16. Classification of a hypervirulent Aeromonas hydrophila pathotype responsible for epidemic outbreaks in warm-water fishes

    Directory of Open Access Journals (Sweden)

    Cody Robert Rasmussen-Ivey

    2016-10-01

    Full Text Available Lineages of hypervirulent Aeromonas hydrophila (vAh are the cause of persistent outbreaks of motile Aeromonas septicemia in warm-water fishes worldwide. Over the last decade, in the People’s Republic of China and in the United States, this virulent lineage of A. hydrophila has resulted in annual losses of millions of tons of farmed carp and catfish. Multiple lines of evidence indicate that US catfish and Asian carp isolates of A. hydrophila affiliated with sequence type 251 (ST251 share a recent common ancestor. To address the genomic context for the putative intercontinental transfer and subsequent geographic spread of this pathogen, we conducted a core genome phylogenetic analysis on 61 Aeromonas spp. genomes, of which 40 were affiliated with A. hydrophila and 26 were epidemic strains. Phylogenetic analyses indicate that all ST251 strains form a coherent lineage affiliated with A. hydrophila. Within this lineage, conserved genetic loci were identified that are unique within A. hydrophila as well as genes that are present in consistently higher copy numbers than in non-epidemic A. hydrophila isolates. In addition, results from analyses of representative ST251 isolates supports that multiple lineages are present within US vAh isolated from Mississippi, whereas vAh isolated from Alabama appear clonal. This is the first report of genomic heterogeneity within US vAh isolates, with some Mississippi isolates showing closer affiliation with the Asian grass carp isolate ZC1 than with other vAh isolated in the US. To evaluate the biological significance of the identified heterogeneity, comparative disease challenges were conducted with representatives of different vAh genotypes revealing that isolate ZC1 yielded significantly lower mortality in channel catfish, relative to Alabama and Mississippi vAh isolates. Like other Asian vAh isolates, the ZC1 lineage contains all core genes for a complete type VI secretion system (T6SS. In contrast, more

  17. Classification of a Hypervirulent Aeromonas hydrophila Pathotype Responsible for Epidemic Outbreaks in Warm-Water Fishes

    Science.gov (United States)

    Rasmussen-Ivey, Cody R.; Hossain, Mohammad J.; Odom, Sara E.; Terhune, Jeffery S.; Hemstreet, William G.; Shoemaker, Craig A.; Zhang, Dunhua; Xu, De-Hai; Griffin, Matt J.; Liu, Yong-Jie; Figueras, Maria J.; Santos, Scott R.; Newton, Joseph C.; Liles, Mark R.

    2016-01-01

    Lineages of hypervirulent Aeromonas hydrophila (vAh) are the cause of persistent outbreaks of motile Aeromonas septicemia in warm-water fishes worldwide. Over the last decade, this virulent lineage of A. hydrophila has resulted in annual losses of millions of tons of farmed carp and catfish in the People's Republic of China and the United States (US). Multiple lines of evidence indicate US catfish and Asian carp isolates of A. hydrophila affiliated with sequence type 251 (ST251) share a recent common ancestor. To address the genomic context for the putative intercontinental transfer and subsequent geographic spread of this pathogen, we conducted a core genome phylogenetic analysis on 61 Aeromonas spp. genomes, of which 40 were affiliated with A. hydrophila, with 26 identified as epidemic strains. Phylogenetic analyses indicate all ST251 strains form a coherent lineage affiliated with A. hydrophila. Within this lineage, conserved genetic loci unique to A. hydrophila were identified, with some genes present in consistently higher copy numbers than in non-epidemic A. hydrophila isolates. In addition, results from analyses of representative ST251 isolates support the conclusion that multiple lineages are present within US vAh isolated from Mississippi, whereas vAh isolated from Alabama appear clonal. This is the first report of genomic heterogeneity within US vAh isolates, with some Mississippi isolates showing closer affiliation with the Asian grass carp isolate ZC1 than other vAh isolated in the US. To evaluate the biological significance of the identified heterogeneity, comparative disease challenges were conducted with representatives of different vAh genotypes. These studies revealed that isolate ZC1 yielded significantly lower mortality in channel catfish, relative to Alabama and Mississippi vAh isolates. Like other Asian vAh isolates, the ZC1 lineage contains all core genes for a complete type VI secretion system (T6SS). In contrast, more virulent US isolates

  18. Usefulness of Chromogenic CromoCen® AGN agar medium for the identification of the genus Aeromonas: Assessment of faecal samples.

    Science.gov (United States)

    Aguilera-Arreola, M G; Portillo-Muñoz, M I; Rodríguez-Martínez, C; Castro-Escarpulli, G

    2012-08-01

    Selective screening media for the detection and identification of Aeromonas strains are needed to guide primary isolation procedures in the clinical laboratory. This study compared the selective CromoCen® AGN chromogenic agar medium for the detection and identification of Aeromonas strains that were isolated from various samples against the conventional selective agar media that are commonly used for the isolation of this organism in food, environmental and clinical samples. The Miles and Misra and ecometric methods were used to evaluate the microbiological performance of CromoCen® AGN chromogenic agar medium, which was shown to be satisfactory. A total of 14 reference Aeromonas strains, 44 wild strains and 106 clinical stool specimens were examined using both non-chromogenic selective agars that are commonly used for Aeromonas isolation and CromoCen® AGN agar. The latter exhibited 94.73% sensitivity and 100% specificity for the various samples. On CromoCen® AGN agar medium, Aeromonas formed colonies with light green, greenish and salmon pigments with or without a surrounding wide transparent zone (halo) of 2-3mm in diameter around the entire border. This medium is recommended for the isolation and potential identification of the Aeromonas genus.

  19. 季磷盐碘对气单胞菌的抑菌杀菌效果研究%Research on Bacteriostatic and Bactericidal Efficacy of Quaternary Phosphorus Salt Iodine on Aeromonas

    Institute of Scientific and Technical Information of China (English)

    谭凤霞; 孟立霞

    2015-01-01

    以气单胞菌属标准株ATCC7966和本实验室分离的气单胞菌为试验菌株,采用营养肉汤二倍稀释法研究季磷盐碘对气单胞菌的抑菌杀菌作用.结果表明,季磷盐碘在低浓度时能抑制气单胞菌的生长增殖,高浓度杀灭细菌,其对7株气单胞菌的最小抑菌浓度(MIC)为0.156 mL/L(Aeromonas sp.T4、Aeromonas sp.T6),0.312 mL/L(ATCC7966、Aeromonas sp.T1、Aeromonas sp.T2、Aeromonas sp.T5)和0.625 mL/L(Aeromonas sp.T3),其最小杀菌浓度(MBC)为1.25 mL/L(Aeromonas sp.T2、Aeromonas sp.T4、Aeromonas sp.T6),2.5 mL/L(Aeromonas sp.T3)和5 mL/L(ATCC7966、Aeromonas sp.T1、Aeromonas sp.T5).本研究结果可为季磷盐碘的合理使用提供参考.

  20. Production of Poly(3-Hydroxybutyrate-co-3-Hydroxyhexanoate) by Aeromonas hydrophila and Recombinant Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    丘远征; 刘力平; 陈国强

    2003-01-01

    Aeromonas hydrophila (A.hydrophila) 4AK4 produced poly(3-hydroxybutyrate-co-3- hydroxyhexanoate) (PHBHHx) with an almost constant 3-hydroxyhexanoate (3HHx) content of 10%-15% from lauric acid and/or soybean oil.Both A.hydrophila 4AK4 and recombinant Escherichia coli (E.coli) JMU193 (pBH32) produced PHBHHx with controllable 3HHx content when fed lauric acid and another co-substrate.With glucose or gluconate as the co-substrate, the 3HHx content in the copolyester produced by A.hydrophila 4AK4 was reduced slightly from 12% to 9%.However, the 3HHx content in the copolyester produced by E.coli JMU193 (pBH32) was significantly reduced from 9% to 2% with fructose as the co-substrate.These results show that regulation of 3HHx content in PHBHHx can be achieved using genetically engineered E.coli.

  1. A novel challenge method with Aeromonas salmonicida in rainbow trout for evaluation of furunculosis vaccines

    DEFF Research Database (Denmark)

    Marana, Moonika Haahr; Skov, Jakob; Chettri, Jiwan Kumar;

    Challenge methods used to induce furunculosis in rainbow trout when testing the potency of vaccines may include exposure to Aeromonas salmonicida by intraperitoneal injection, cohabitation or bath immersion. Intraperitoneal injection is effective but will not reflect systemic immunity because...... inflammatory cells at the vaccine injection site may combat injected bacteria fast. The cohabitation and bath immersion methods both mimic the natural infection route but are less effective in inducing the disease. We have tested a new challenge method mimicking that rainbow trout in fish farms might...... to be efficient in inducing a more natural disease progression in fish and a stable mortality. The method could differentiate efficacies of different vaccines with regard to adjuvant formulations and content of antigen....

  2. A Report of Peritonitis from Aeromonas sobria in a Peritoneal Dialysis (PD) Patient with Necrotizing Fasciitis.

    Science.gov (United States)

    Janma, Jirayut; Linasmita, Patcharasarn; Changsirikulchai, Siribha

    2015-11-01

    A 70-years of age, male patient with underlying type 2 diabetes mellitus, hypertension, dyslipidemia and ischemic heart disease had undergone continuous ambulatory peritoneal dialysis (CAPD)for 3 years without any episodes of peritonitis. He was diagnosed with necrotizing fasciitis and later developed peritonitis after receiving a laceration from an aquatic injury suffered during the flood disaster of 2011. The blood culture, necrotic tissue and the clear dialysate collected upon admission had shown Aeromonas sobria. The route of peritonitis may be from the hematogenous spread of A. sobria resulting in necrotizing fasciitis. A. sobria should be considered as the pathogen of peritonitis in PD patients who have history of wounds from contaminated water. We suggest that the PD patients who present with septicemia and did not meet the criteria for peritonitis, the initial dialysate effluent should be sent for culture. The benefit of this is to allow early recognition and treatment of peritonitis.

  3. Subunit vaccine candidates against Aeromonas salmonicida in rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Marana, Moonika Haahr; Jørgensen, Louise von Gersdorff; Skov, Jakob;

    2017-01-01

    Aeromonas salmonicida subsp. salmonicida is the etiological agent of furunculosis and a major fish health problem in salmonid aquaculture worldwide. Injection vaccination with commercial mineral oil-adjuvanted bacterin vaccines has been partly successful in preventing the disease but in Danish...... rainbow trout (Oncorhynchus mykiss, Walbaum) aquaculture furunculosis outbreaks still occur. In this study we tested the efficacy of experimental subunit vaccines against A. salmonicida infection in rainbow trout. We utilized in silico screening of the proteome of A. salmonicida subsp. salmonicida strain...... A449 and identified potential protective protein antigens that were tested by in vivo challenge trial. A total of 14 proteins were recombinantly expressed in Escherichia coli and prepared in 3 different subunit vaccine combinations to immunize 3 groups of rainbow trout by intraperitoneal (i...

  4. Cylindrospermopsin Biodegradation Abilities of Aeromonas sp. Isolated from Rusałka Lake.

    Science.gov (United States)

    Dziga, Dariusz; Kokocinski, Mikolaj; Maksylewicz, Anna; Czaja-Prokop, Urszula; Barylski, Jakub

    2016-02-25

    The occurrence of the cyanobacterial toxin cylindrospermopsin (CYN) in freshwater reservoirs is a common phenomenon. However, the biodegradation of this toxin in environmental samples has been observed only occasionally. In this work the biodegradation ability of cylindrospermopsin was investigated based on isolates from lakes with previous cyanotoxin history. Bacterial strains were identified based on the 16S rDNA and rpoD gene comparison. CYN biodegradation was monitored using the HPLC method. The R6 strain identified as Aeromonas sp. was documented as being capable of CYN removal. This biodegradation was dependent on the pH and temperature. Additionally, the stimulation of the growth of the R6 strain in the presence of CYN was indicated. Our discovery supports the hypothesis that (in analogy to the well-known phenomenon of microcystin biodegradation) in lakes dominated by potential CYN-producing cyanobacteria, the processes of microbial utilization of this toxin may occur.

  5. Aeromonas proteolyrica bacteria in aerospace environments. [possible genetic alterations and effects on man

    Science.gov (United States)

    Foster, B. G.

    1974-01-01

    Preflight studies on Aeromonas proteolytica are reported to investigate the possibility of genetic alterations resulting in increased proteolysis in spacecraft environments. This organism may be present on human tissue and could pose medical problems if its endopeptidase and a hemolysin were to be produced in ususually high quantities or altered in such a way as to be more effective in their activities. Considered are: (1) Development of a nutrative holding medium for suspension of organisms; (2) the establishment of baseline information for the standardization of the assay for endopeptidase levels and hemolytic titers; (3) formulation of a method by which intracutaneous hemorrhage could be quantitated in guinea pig tissue; and (4) the responses of these organisms to parameters of spaceflight and experimentation.

  6. Aeromonas dhakensis pneumonia and sepsis in a neonate Risso's dolphin Grampus griseus from the Mediterranean Sea.

    Science.gov (United States)

    Pérez, Lola; Abarca, M Lourdes; Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Figueras, M José; Domingo, Mariano

    2015-09-17

    A neonate Risso's dolphin Grampus griseus was found stranded alive on a beach in Catalonia, Spain. Rehabilitation attempts were unsuccessful and it died 2 d later, showing pneumonia and sepsis. A pure bacterial culture was obtained from all tissues and blood and identified as Aeromonas hydrophila using the API 20NE. However, sequencing the rpoD gene showed that the strain in fact belongs to A. dhakensis, making this the first report of fatal haemorrhagic-necrotizing pneumonia and sepsis due to this species in a marine mammal. The A. dhakensis strain GMV-704 produced β-haemolysis, possessed several virulence genes and showed sensitivity to several antimicrobials. This study provides a new potential host for A. dhakensis, and its potential virulence in dolphins and its presence in the marine environment may warrant considering this species a potential threat to marine mammals.

  7. Detection and characterization of potentially pathogenic Aeromonas sobria isolated from fish Hypophthalmichthys molitrix (Cypriniformes: Cyprinidae).

    Science.gov (United States)

    Dar, Gowhar H; Dar, Shoaib A; Kamili, Azra N; Chishti, Mohammad Z; Ahmad, Fayaz

    2016-02-01

    The current study focuses on the detection and characterization of potentially pathogenic Aeromonas sobria from fish silver carp (Hypophthalmichthys molitrix). Assessment of clinical, microbiological, pathological and biochemical characteristics of A. sobria were taken into account in order to understand the epidemiology, frequency and occurrence of this infection. Clinically the infected fish (H. molitrix) was observed for various types of symptoms. A total of 33 colonies of A. sobria strain were isolated from 20 cultured H. molitrix, collected from controlled fish pond. Microscopic examination revealed that the strains were rod-shaped, Gram negative bacteria. The revealed percent probability identification of A. sobria from the biochemical characterization in VITEK system was 93% with gram negative (GN) card. The histopathology of Gills caused by this bacterium, A. sobria indicate haemorrhagic gill epithelia and epithelial hyperplasia. Lamelar epithelial hypertrophy and hyperplasia with degenerative changes of the epithelium and hypertrophic epitheliocystis infected cells on gills of H. molitrix were observed during the present study.

  8. In Vitro Antibacterial Effect of Effective Microorganisms( EM) on Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    Zhu; Zhixiu; He; Houjun; Zhang; Wenbo; Wu; Xiangdong; Wan; Gen; Deng; Shunzhou; Liu; Songlin

    2014-01-01

    In order to understand in vitro antibacterial effect of antibiotics and EM on Aeromonas hydrophila,14 isolates of A. hydrophila were isolated from diseased fish and aquaculture in the study. PCR amplification results of aerolysin gene( Aero gene) of isolates indicated that 7 out of 14 isolates were pathogenic A.hydrophila. In vitro antibacterial test indicated that 14 isolates were resistance to penicillin G,ampicillin,cephradine,cefazolin,tetracycline,terimethoprim,lincomycin and cephalexin,but showed high sensitivity to cefotaxime and furazolidone. In vitro antibacterial effect of EM on 14 isolates of A. hydrophila was positively correlated with concentration,and EM with the concentration greater than 60% had antibacterial effect on 14 isolates.

  9. Pancarditis in a patient with tropical pyomyositis due to Aeromonas infection

    Directory of Open Access Journals (Sweden)

    Nikhil Gupta

    2015-01-01

    Full Text Available Tropical pyomyositis is a suppurative disease of the skeletal muscles. The most common site of the infection being muscles of the thigh. Staphylococcus aureus is the most common organism isolated. Aeromonas is one of the rarest organisms described as the etiologic agent for this disease. Rarely, cardiac involvement in pyomyositis has been described in the form of myocarditis and pyopericardium. Pancarditis is a very rare event in the natural course of pyomyositis. To the best of our knowledge, there is a single case report in world literature regarding involvement of all the layers of the heart in pyomyositis. We report a case of a 30-year-old immunocompetent male who had pyomyositis and developed pancarditis, which was managed successfully with conservative management.

  10. Infection of sea lamprey with an unusual strain of Aeromonas salmonicida

    Science.gov (United States)

    Diamanka, Arfang; Loch, Thomas P.; Cipriano, Rocco C.; Winters, Andrew D.; Faisal, Mohamed

    2014-01-01

    The invasion of the Laurentian Great Lakes by the fish-parasitic sea lamprey has led to catastrophic consequences, including the potential introduction of fish pathogens. Aeromonas salmonicida is a bacterial fish pathogen that causes devastating losses worldwide. Currently, there are five accepted subspecies of Aeromonas salmonicida: A. salmonicida subsp. salmonicida, masoucida, smithia, achromogenes, and pectinolytica. We discuss the discovery of an isolate of A. salmonicida that is pathogenic to rainbow trout (Oncorhynchus mykiss) and exhibits unique phenotypic and molecular characteristics. We examined 181 adult sea lamprey (Petromyzon marinus) from the Humber River (Lake Ontario watershed) and 162 adult sea lamprey from Duffins Creek (Lake Ontario watershed) during the spring seasons of 2005–11. Among those, 4/343 (1.2%) sea lamprey were culture positive for A. salmonicida, whereby biochemical and molecular studies identified three of the isolates as A. salmonicida subsp. salmonicida. The remaining isolate (As-SL1) recovered from Humber River sea lamprey was phenotypically more similar to A. salmonicida subsp. salmonicida than to the four other A. salmonicida subspecies. However, unlike A. salmonicida subsp. salmonicida, As-SL1 was sucrose positive, produced an acid-over-acid reaction on triple-sugar iron medium and did not amplify with A. salmonicida subsp. salmonicida specific primers. Phylogenetic analysis based on partial stretches of the 16S rRNA and DNA gyrase subunit B genes further confirmed that the As-SL1 isolate was not A. salmonicida subsp. masoucida, smithia, achromogenes, or pectinolytica. Based on our analyses, the As-SL1 isolate is either an unusual strain of A. salmonicida subsp. salmonicida or a novel A. salmonicida subspecies. The four A. salmonicida isolates that were recovered from sea lamprey were pathogenic to rainbow trout in experimental challenge studies. Our study also underscores the potential role of sea lamprey in the ecology of

  11. Chemical modification of polyvinyl chloride and silicone elastomer in inhibiting adhesion of Aeromonas hydrophila.

    Science.gov (United States)

    Kregiel, Dorota; Berlowska, Joanna; Mizerska, Urszula; Fortuniak, Witold; Chojnowski, Julian; Ambroziak, Wojciech

    2013-07-01

    Disease-causing bacteria of the genus Aeromonas are able to adhere to pipe materials, colonizing the surfaces and forming biofilms in water distribution systems. The aim of our research was to study how the modification of materials used commonly in the water industry can reduce bacterial cell attachment. Polyvinyl chloride and silicone elastomer surfaces were activated and modified with reactive organo-silanes by coupling or co-crosslinking silanes with the native material. Both the native and modified surfaces were tested using the bacterial strain Aeromonas hydrophila, which was isolated from the Polish water distribution system. The surface tension of both the native and modified surfaces was measured. To determine cell viability and bacterial adhesion two methods were used, namely plate count and luminometry. Results were expressed in colony-forming units (c.f.u.) and in relative light units (RLU) per cm(2). Almost all the chemically modified surfaces exhibited higher anti-adhesive and anti-microbial properties in comparison to the native surfaces. Among the modifying agents examined, poly[dimethylsiloxane-co-(N,N-dimethyl-N-n-octylammoniopropyl chloride) methylsiloxane)] terminated with hydroxydimethylsilyl groups (20 %) in silicone elastomer gave the most desirable results. The surface tension of this modifier, was comparable to the non-polar native surface. However, almost half of this value was due to the result of polar forces. In this case, in an adhesion analysis, only 1 RLU cm(-2) and less than 1 c.f.u. cm(-2) were noted. For the native gumosil, the results were 9,375 RLU cm(-2) and 2.5 × 10(8) c.f.u. cm(-2), respectively. The antibacterial activity of active organo-silanes was associated only with the carrier surface because no antibacterial compounds were detected in liquid culture media, in concentrations that were able to inhibit cell growth.

  12. Protection of ornamental gold fish Carassius auratus against Aeromonas hydrophila by treating Ixora coccinea active principles.

    Science.gov (United States)

    Anusha, Paulraj; Thangaviji, Vijayaragavan; Velmurugan, Subramanian; Michaelbabu, Mariavincent; Citarasu, Thavasimuthu

    2014-02-01

    Herbals such as Ixora coccinea, Daemia extensa and Tridax procumbens were selected to screen in vitro antibacterial and immunostimulant activity against the freshwater fish pathogen Aeromonas hydrophila using different organic polar and non-polar solvents. Initial screening results revealed that, ethyl acetate extracts and its purified fraction of I. coccinea was able to suppress the A. hydrophila strains at more than 15 mm of zone of inhibition and positive immunostimulant activity. The purified active fraction, which eluted from H40: EA60 mobile phase was structurally characterized by GC-MS analysis. Two compounds such as Diethyl Phthalate (1,2-Benzene dicarboxylic acid, monobutyl ester) and Dibutyl Phthalate were characterized using NIST database search. In order to study the in vivo immunostimulant influence of the compounds, the crude extracts (ICE) and purified fractions (ICF) were incorporated to the artificial diets at the concentration of 400 mg kg⁻¹ and fed to the ornamental gold fish Carassius auratus for 30 days. After termination of feeding experiment, they were challenged with highly virulent A. hydrophila AHV-1 which was isolated from infected gold fish and studied the survival, specific bacterial load reduction, serum biochemistry, haematology, immunology and histological parameters. The control diet fed fishes succumbed to death within five days at 100% mortality whereas ICE and ICF fed groups survived 60 and 80% respectively after 10 days. The diets also helped to decrease the Aeromonas load after challenge and significantly (P ≤ 0.01) improved the serum albumin, globulin and protein. The diets also helped to increase the RBC and haemoglobin level significantly (P ≤ 0.05) from the control group. Surprisingly the immunological parameters like phagocytic activity, serum bactericidal activity and lysozyme activity were significantly increased (P ≤ 0.001) in the experimental diets. Macrophages and erythrocytes were abundantly expressed in the

  13. The occurrence of Aeromonas spp. in the bottled mineral water, well water and tap water from the municipal supplies

    Directory of Open Access Journals (Sweden)

    Denise de Oliveira Scoaris

    2008-10-01

    Full Text Available The aim of this work was to study the occurrence of Aeromonas sp in the bottled mineral water, well water and tap water from the municipal supplies. Positive samples were found for Aeromonas spp. 12.7% from the mineral water, 8.3% from the artesian water and 6.5% from the tap water. The recovery of Aeromonas spp. was significantly higher in the bottled mineral and artesian water than in the tap water from municipal supplies. The occurrence of the Aeromonas spp. did not correlate significantly with the contamination indicator bacteria (i.e. total coliforms in the artesian water samples. However, a significant correlation was found between Aeromonas spp. and total coliforms in the both mineral water and tap water samples. The presence or absence of a correlation between the indicator bacteria and Aeromonas could reflect the occasional appearance of the pathogen in the drinking water and the different rates of survival and recovery of these agents compared with those fecal indicators. The finding that 41.6, 14.8 and 9.0 % of the artesian water, bottled mineral water and tap water, respectively, sampled in the current study failed to meet the Brazilian standard for total coliforms in the drinking water should therefore be of concern.A porcentagem de amostras positivas para Aeromonas foi de 12.7% para água mineral, 8.3% para água de poço artesiano e 6.5% para água do sistema público de abastecimento. O isolamento de Aeromonas spp. foi significativamente maior em água mineral e água de poço artesiano do que em água do sistema público. A ocorrência de Aeromonas spp. não teve correlação significativa com os indicadores de contaminação tradicionalmente utilizados (coliformes totais em amostras de água de poço artesiano. No entanto, esta correlação foi positiva e significativa em água mineral e água do sistema público. A presença ou ausência de correlação entre bactérias indicadoras e a presença de Aeromonas pode refletir o

  14. Aeromonas veronii N8活性菌体对Zn2+的吸附特征%Biosorption characteristic of Zn2+ by viable cells of Aeromonas veronii N8

    Institute of Scientific and Technical Information of China (English)

    柴德芳; 宋萍; 申露文; 林欣; 封磊

    2016-01-01

    Aeromonas veronii N8菌为对象,对菌体的性质及其吸附Zn2+特征进行研究.结果表明,Aeromonas veronii菌的生长周期在66 h左右,并且Zn2+对该菌的最低抑菌质量浓度为150 mg/L;N8菌体对Zn2+的吸附随时间的增加,吸附率逐渐增大,并且在90 min后达到吸附平衡.菌体的吸附率随菌体质量浓度的增加而变大,并随Zn2+质量浓度的增加而变小.吸附前、后扫描电镜及能谱分析(scanning electron microscope-energy dispersive X-ray,SEM-EDX)的表征结果显示,在菌体的细胞壁表面检测到Zn元素,说明Aeromonas veronii N8菌体对Zn2+具有一定的吸附作用.菌体的Zn2+吸附过程可采用Toth模型进行描述.

  15. Protection against atypical Aeromonas salmonicida infection in carp (Cyprinus carpio L.) by oral administration of humus extract.

    Science.gov (United States)

    Kodama, Hiroshi; Denso; Nakagawa, Tsuyoshi

    2007-04-01

    Humic substances are formed during the decomposition of organic matter in humus, and are found in many natural environments in which organic materials and microorganisms have been present. In the present study, oral administration of humus extract to common carp (Cyprinus carpio L.) induced effective protection against experimental atypical Aeromonas salmonicida infection. Mortality of fish and development of skin lesions such as hemorrhages and ulcers were significantly suppressed in carp treated with 10%, 5% or 1% humus extract adsorbed on dry feeding pellets. The median surviving days was also greater in fish treated with 10% or 5% humus extract than in untreated fish. Atypical A. salmonicida was isolated from ulcerative lesions of part of dead fish, but Aeromonas hydrophila and Flavobacterium sp. were also isolated from these fish, verifying bacterial population changes during the progression of skin lesions. These results clearly show that treatment of fish with humus extract is effective in preventing A. salmonicida disease.

  16. Occurrence and significance of atypical Aeromonas salmonicida in non-salmonid and salmonid fish species : A review

    OpenAIRE

    Wiklund, T.; Dalsgaard, Inger

    1998-01-01

    Bacterial strains of Aeromonas salmonicida included in the recognized subsp. achromogenes, subsp, masoucida, and subsp. smithia in addition to the large number of strains not included in any of the described subspecies are referred to as atypical A. salmonicida. The atypical strains form a very heterogeneous group with respect to biochemical characteristics, growth conditions, and production of extracellular proteases. Consequently, the present taxonomy of the species A. salmonicida is rather...

  17. Skrining Fitokimia Metabolit Sekunder Dalam Daun Binahong (Anredera cordifolia (Ten) Steenis) Untuk Uji In Vitro Daya Hambat Pertumbuhan Aeromonas Hydrophila

    OpenAIRE

    Ginting, Prita Yulianti Anasta

    2016-01-01

    Binahong leaves are one of natural product to be used to treat the disease of living organisme due to having secondary metabolite to show antibacterial activity. The purpose of this research was to study secondary metabolite of Binahong leaves of which showing antibacterial, to analysis effectivity of antibacterial Binahong leaves extract to inhibit growth of bacteria Aeromonas hydrophila. An experimental laboratory with six treatments and three replications for in vitro was tested. A pap...

  18. Use of Aeromonas spp. as general indicators of antimicrobial susceptibility among bacteria in aquatic environments in Thailand

    Directory of Open Access Journals (Sweden)

    Masaru eUsui

    2016-05-01

    Full Text Available Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria (ARB, and thereby disseminating antimicrobial resistance genes (ARGs. In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals and 12 sites (6 sites at city canals, 2 sites at chicken farms, 2 sites at pig farms, and 2 samples from sites at pig farms that were subsequently treated at a biogas plant in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Moreover, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp. Notably, however, the concentration and resistance rates of tetracycline in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments.

  19. Use of Aeromonas spp. as General Indicators of Antimicrobial Susceptibility among Bacteria in Aquatic Environments in Thailand.

    Science.gov (United States)

    Usui, Masaru; Tagaki, Chie; Fukuda, Akira; Okubo, Torahiko; Boonla, Chanchai; Suzuki, Satoru; Seki, Kanako; Takada, Hideshige; Tamura, Yutaka

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria, and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals) and 12 sites (6 sites at city canals; 2 sites at chicken farms; 2 sites at pig farms; and 2 samples from sites at pig farms, which were subsequently treated at a biogas plant) in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Notably, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp.; however, both the concentration and rates of tetracycline resistance in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments.

  20. Identification of antibiotic resistance cassettes in class 1 integrons in Aeromonas spp. strains isolated from fresh fish (Cyprinus carpio L.).

    Science.gov (United States)

    Sarria-Guzmán, Yohanna; López-Ramírez, María Patricia; Chávez-Romero, Yosef; Ruiz-Romero, Erick; Dendooven, Luc; Bello-López, Juan Manuel

    2014-05-01

    Forty-six Aeromonas spp. strains were isolated from fresh fish and investigated for their antimicrobial susceptibility, detection of Class 1 integrons by PCR, and arrangement of gene cassettes. Selected isolates were further characterized by enterobacterial repetitive intergenic consensus-PCR. Twenty isolates were found to carry Class 1 integrons. Amplification of the variable regions of the integrons revealed diverse bands ranging in size from 150 to 1,958 pb. Sequence analysis of the variable regions revealed the presence of several gene cassettes, such as adenylyl transferases (aadA2 and aadA5), dihydrofolate reductases (dfrA17 and dfrA1), chloramphenicol acetyl transferase (catB3), β-lactamase (oxa2), lincosamide nucleotidil transferase (linF), aminoglycoside-modifying enzyme (apha15), and oxacillinase (bla OXA-10). Two open reading frames with an unknown function were identified as orfC and orfD. The aadA2 cassette was the most common integron found in this study. Interestingly, five integrons were detected in the plasmids that might be involved in the transfer of resistance genes to other bacteria. This is a first report of cassette encoding for lincosamides (linF) resistance in Aeromonas spp. Implications on the incidence of integrons in isolates of Aeromonas spp. from fresh fish for human consumption, and its possible consequences to human health are discussed.

  1. Detection and distribution of putative virulence associated genes in Aeromonas species from freshwater and wastewater treatment plant.

    Science.gov (United States)

    Igbinosa, Isoken H; Okoh, Anthony I

    2013-11-01

    The detection of genes responsible for Aeromonas virulence is a vital tool in establishing the potential pathogenicity of the bacteria, as these virulence genes may act alone or in synergy in the establishment of infections. Freshwater and wastewater mixed liquor samples were collected from Kat river and Fort Beaufort wastewater treatment plant in the Eastern Cape Province of South Africa. Polymerase chain reaction was utilized for the amplification of the different genes coding for virulence. All virulence associated genes screened (alt, lip, fla, aer, ast, hlyA) were detected in at least one Aeromonas isolates. In fresh water sample, virulence genes were distributed as follows: lip (67%), aer (43%), alt (33%), fla (62%), ast (10%), and hlyA (86%), while in wastewater samples the occurrence were as follows: lip (92%), aer (21%), alt (54%), fla (83%), ast (29%), and hlyA (88%). The presence of these virulence genes in environmental Aeromonas isolates is of concern to public health as these organisms are potential pathogens in the environment and the virulence determinants could be transferred to aquatic organisms and humans by one mechanism or the other.

  2. 气单胞菌(Aeromonas sp.D-4)降解LAS的研究

    Institute of Scientific and Technical Information of China (English)

    李峤; 邓家齐; 王德铭

    1988-01-01

    Aeromonas sp.D-4不能以LAS作为唯一碳源,它对LAS的利用是通过共代谢来完成的。LAS对D-4具有毒害作用,而且,起始LAS浓度越高,毒害作用越大。LAS的最大去除串与起始LAS浓度呈负相关。当起始LAS在40-120mg/L之间时,去除串较高;如果起始LAS在40mg/L左右,则去除率可达s096以上。研究还表明,Aeromonas sp.D-4纯培养对LAS的去除率(最大值84.97%)大于混合菌(最大值78.57%)。耗氧呼吸测定证实了Aeromonas sp.D-4对于LAS的共代谢和LAS对细菌的毒性,同时也证实了培养基中LAS的消失是细菌作用的结果。

  3. Research Progress on Aeromonas hydrophila%嗜水气单胞菌的研究进展

    Institute of Scientific and Technical Information of China (English)

    姜艳丽; 李丽丽

    2015-01-01

    为有效预防嗜水气单胞菌引起传染病的发生,以减少对人畜的损害,通过回顾嗜水气单胞菌的分类地位(嗜温性和运动性的气单胞菌属的模式菌)、生物学性质,对其主要毒力因子(外毒素及胞外蛋白酶)和鉴定技术(生化鉴定、免疫血清技术和分子生物学技术)的研究成果进行了综述。%In order to prevent the infectious dieases caused by Aeromonas hydrophila ,and reduce the damage to human and animals ,the taxonomic status and biological character of Aeromonas hydrophila were reviewed ,the research of virulence factor (exotoxin and extracellular protease)and identification of Aeromonas hydrophila were summarized ,in cluding biochenrical identification ,immune serum and molecular biology techniques .

  4. Determination of microbial diversity of Aeromonas strains on the basis of multilocus sequence typing, phenotype, and presence of putative virulence genes.

    Science.gov (United States)

    Martino, Maria Elena; Fasolato, Luca; Montemurro, Filomena; Rosteghin, Marina; Manfrin, Amedeo; Patarnello, Tomaso; Novelli, Enrico; Cardazzo, Barbara

    2011-07-01

    The genus Aeromonas has been described as comprising several species associated with the aquatic environment, which represents their principal reservoir. Aeromonas spp. are commonly isolated from diseased and healthy fish, but the involvement of such bacteria in human infection and gastroenteritis has frequently been reported. The primary challenge in establishing an unequivocal link between the Aeromonas genus and pathogenesis in humans is the extremely complicated taxonomy. With the aim of clarifying taxonomic relationships among the strains and phenotypes, a multilocus sequencing approach was developed and applied to characterize 23 type and reference strains of Aeromonas spp. and a collection of 77 field strains isolated from fish, crustaceans, and mollusks. All strains were also screened for putative determinants of virulence by PCR (ast, ahh1, act, asa1, eno, ascV, and aexT) and the production of acylated homoserine lactones (AHLs). In addition, the phenotypic fingerprinting obtained from 29 biochemical tests was submitted to the nonparametric combination (NPC) test methodology to define the statistical differences among the identified genetic clusters. Multilocus sequence typing (MLST) achieved precise strain genotyping, and the phylogenetic analysis of concatenated sequences delineated the relationship among the taxa belonging to the genus Aeromonas, providing a powerful tool for outbreak traceability, host range diffusion, and ecological studies. The NPC test showed the feasibility of phenotypic differentiation among the majority of the MLST clusters by using a selection of tests or the entire biochemical fingerprinting. A Web-based MLST sequence database (http://pubmlst.org/aeromonas) specific for the Aeromonas genus was developed and implemented with all the results.

  5. Adhesion, invasion, intracellular survival and cytotoxic activity of strains of Aeromonas spp. in HEp-2, Caco-2 and T-84 cell lines.

    Science.gov (United States)

    dos Santos, Paula Azevedo; Pereira, Ana Claudia Machado; Ferreira, Andréa Fonseca; de Mattos Alves, Maria Angélica; Rosa, Ana Cláudia Paula; Freitas-Almeida, Angela Corrêa

    2015-05-01

    The genus Aeromonas contains important pathogen for both humans and other animals, being responsible for the etiology of intestinal and extraintestinal diseases. The pathology caused by these bacteria involves several virulence factors, such as the ability to produce toxins, adhesion and invasion. The properties conferred by these factors have been extensively studied in experiments of interaction between bacterial strains and cell culture. We evaluate the interaction of eight Aeromonas spp. strains, previously isolated from human faeces, food and water with HEp-2, Caco-2 and T-84 cell lines. Cytotoxic effects, the pattern of adhesion, invasive capacity and intracellular survival were analyzed. The results showed that Aeromonas strains were adherent to three cells lines in 6 h of incubation, displaying the aggregative adherence pattern. Among eight strains studied, 50% produced cytotoxic effects on HEp-2 cells, while none of the strains produced cytotoxic effects on Caco-2 and T-84 cells at 48 h. This study demonstrated that subsets of Aeromonas isolated from different sources were able to invade intestinal (T-84, Caco-2) and epithelial (HEp-2) cell lines cultivated in vitro surviving in intracellular environments up to 72 h. Finally, our results support the pathogenic potential of Aeromonas, especially those of food and clinical sources.

  6. First record of the rare species Aeromonas schubertii from mussels: phenotypic and genetic reevaluation of the species and a review of the literature.

    Science.gov (United States)

    Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Figueras, María José

    2016-05-01

    In a study where the prevalence of Aeromonas in shellfish was analysed, three isolates of Aeromonas schubertii were identified, representing this the first report of this species from mussels. This species was originally described in 1988 from strains isolated from extra-intestinal human infections and since then has been cited in only 18 occasions. For many years, A. schubertii was the only mannitol-negative species of the genus. However, three additional mannitol-negative species (Aeromonas simiae, Aeromonas diversa and Aeromonas australiensis) have been described. This, together with the fact that A. schubertii is a rare human pathogenic species, motivated the present study to characterize its biochemical behaviour and differentiation from the other mannitol-negative species. The molecular similarity (16S rRNA, rpoD and gyrB genes) of the strains, presence of virulence genes and antimicrobial resistance were determined. All A. schubertii strains showed the same phenotypic behaviour, i.e. they use citrate, are positive for lysine decarboxylase and DL-lactate, but negative for production of mannitol, indole and acid from sucrose and could be easily differentiated from other mannitol-negative species. All strains carried the aerA and lafA virulence genes and showed susceptibility to all antibiotics tested. Seafood could be a transmission route of this bacterium to humans.

  7. Non-specific immune response of bullfrog Rana catesbeiana to intraperitoneal injection of bacterium Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups. Each bullfrog in bacterium-injected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml, while each one in control group injected i.p. with 0.2 ml sterile saline solution (0.85%, w/v). Three bullfrogs in both groups were sampled at 0, 1, 3, 7, 11, 15 and 20 days post-injection (dpi) for the evaluation of non-specific immune parameters. It was observed that intraperitoneal injection of A. hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood. Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group. However, a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes. No significant difference in changes in the number of peripheral erythrocytes, serum superoxide dismutase (SOD) activity, and lysozyme activity was detected between the two groups. It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A. hydrophila infection.

  8. Effect of plasma processing and organosilane modifications of polyethylene on Aeromonas hydrophila biofilm formation.

    Science.gov (United States)

    Kregiel, Dorota; Niedzielska, Kamila

    2014-01-01

    The aim of our research was to study how the modifications of polyethylene--a material commonly used in medicine and water industry--influence bacterial cell attachment and biofilm formation. The native surface was activated and modified using two-step process consisting in the activation of native surface with a H2O vapor plasma followed by its treatment with various organosilanes, namely, [3(tertbutylamine-2hydroxy) propyloxypropyl] diethoxymethylsilane, 1H,1H,2H,2H-perfluorooctylmethyldimethoxysilane, dimethoxydimethylsilane, and isobutylmethyldimethoxysilane. The effect of polyethylene modification after chemical treatment was analyzed using surface tension measurement. The adhesive properties of Aeromonas hydrophila LOCK0968 were studied in water with a low concentration of organic compounds, using luminometric and microscopic methods, and the viability of the adhered bacterial cells was evaluated using the colony forming units method. After two-week incubation the chemically modified materials exhibited better antiadhesive and antibacterial characteristics in comparison to the native surface. Among the examined modifying agents, dimethoxydimethylsilane showed the best desired properties.

  9. Isolation and characterization of Aeromonas schubertii from diseased snakehead, Channa maculata (Lacepède).

    Science.gov (United States)

    Chen, Y F; Liang, R S; Zhuo, X L; Wu, X T; Zou, J X

    2012-06-01

    Pure bacterial cultures were isolated from diseased snakeheads, Channa maculata (Lacepède), suffering high mortality in a farm in Zhongshan, southern China. Three isolates, namely ZS20100725, ZS20100725-1 and ZS20100725-2, were identified as Aeromonas schubertii. All the isolates showed high 16S rRNA sequence similarities with A. schubertii. The isolates exhibited strong virulence to snakeheads in experimental challenges with LD(50) ranging between 1.4 × 10(4) and 6.4 × 10(6) CFU g(-1). Two of the isolates were positive for haemolysin, elastase, lipase and lecithinase by phenotypic determination, which was further confirmed by PCR amplification of the haemolysin and elastase genes. In sterile liquid medium, the best growth conditions of strain ZS20100725 were 30 °C, pH 7 and 0.5% salinity (w/v). Antibiotic susceptibility tests showed that strain ZS20100725 was susceptible to cefoxitin, cefoperazone and chloramphenicol. Furthermore, histopathology of diseased snakeheads infected with A. schubertii showed necrosis and congestion in liver, kidney and spleen and also damage to the cardiac muscle, intestine and gills.

  10. Antibacterial activities of bioactive compounds extracted from Marine algae Gracilaria salicornia against Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Somayeh Rasooli

    2015-04-01

    Full Text Available Herbal medicinal products have attracted significant research interest in recent years. Considering the efficiency of algae products in controlling pathogenic bacteria and also easy access to large resources of algae, this study was conducted to evaluate the effects of methanolic, chloroformic and aqueous extracts of Gracilaria salicornia against Aeromonas hydrophila, a heterotrophic, Gram-negative, rod-shaped bacterium found mainly in warm climate. Algae samples were collected from Qeshm Island coastlines and transferred to the laboratory. Standard methods were used to obtain the algae extract. Antibacterial activities of various extracts were tested against the bacterium using well diffusion assay method. Significant differences were observed in antibacterial activities of different extracts (P<0.05. The diameter of zone of growth inhibition varied in correlation with concentration of the extracts (50, 100, 200 and 300 mg.ml-1. The best inhibition zone was observed at 100, 200 and 300 mg.ml-1 methanolic and 300 mg.ml-1 aqueous extracts.

  11. Effect of Plasma Processing and Organosilane Modifications of Polyethylene on Aeromonas hydrophila Biofilm Formation

    Directory of Open Access Journals (Sweden)

    Dorota Kregiel

    2014-01-01

    Full Text Available The aim of our research was to study how the modifications of polyethylene—a material commonly used in medicine and water industry—influence bacterial cell attachment and biofilm formation. The native surface was activated and modified using two-step process consisting in the activation of native surface with a H2O vapor plasma followed by its treatment with various organosilanes, namely, [3(tertbutylamine-2hydroxy propyloxypropyl] diethoxymethylsilane, 1H,1H,2H,2H-perfluorooctylmethyldimethoxysilane, dimethoxydimethylsilane, and isobutylmethyldimethoxysilane. The effect of polyethylene modification after chemical treatment was analyzed using surface tension measurement. The adhesive properties of Aeromonas hydrophila LOCK0968 were studied in water with a low concentration of organic compounds, using luminometric and microscopic methods, and the viability of the adhered bacterial cells was evaluated using the colony forming units method. After two-week incubation the chemically modified materials exhibited better antiadhesive and antibacterial characteristics in comparison to the native surface. Among the examined modifying agents, dimethoxydimethylsilane showed the best desired properties.

  12. Detection and quantification of Aeromonas salmonicida in fish tissue by real-time PCR.

    Science.gov (United States)

    Bartkova, S; Kokotovic, B; Skall, H F; Lorenzen, N; Dalsgaard, I

    2017-02-01

    Furunculosis, a septicaemic infection caused by the bacterium Aeromonas salmonicida subsp. salmonicida, currently causes problems in Danish seawater rainbow trout production. Detection has mainly been achieved by bacterial culture, but more rapid and sensitive methods are needed. A previously developed real-time PCR assay targeting the plasmid encoded aopP gene of A. salmonicida was, in parallel with culturing, used for the examination of five organs of 40 fish from Danish freshwater and seawater farms. Real-time PCR showed overall a higher frequency of positives than culturing (65% of positive fish by real-time PCR compared to 30% by a culture approach). Also, no real-time PCR-negative samples were found positive by culturing. A. salmonicida was detected by real-time PCR, though not by culturing, in freshwater fish showing no signs of furunculosis, indicating possible presence of carrier fish. In seawater fish examined after an outbreak and antibiotics treatment, real-time PCR showed the presence of the bacterium in all examined organs (1-482 genomic units mg(-1) ). With a limit of detection of 40 target copies (1-2 genomic units) per reaction, a high reproducibility and an excellent efficiency, the present real-time PCR assay provides a sensitive tool for the detection of A. salmonicida.

  13. Subunit vaccine candidates against Aeromonas salmonicida in rainbow trout Oncorhynchus mykiss

    Science.gov (United States)

    Jørgensen, Louise von Gersdorff; Skov, Jakob; Chettri, Jiwan Kumar; Holm Mattsson, Andreas; Dalsgaard, Inger; Kania, Per Walter; Buchmann, Kurt

    2017-01-01

    Aeromonas salmonicida subsp. salmonicida is the etiological agent of furunculosis and a major fish health problem in salmonid aquaculture worldwide. Injection vaccination with commercial mineral oil-adjuvanted bacterin vaccines has been partly successful in preventing the disease but in Danish rainbow trout (Oncorhynchus mykiss, Walbaum) aquaculture furunculosis outbreaks still occur. In this study we tested the efficacy of experimental subunit vaccines against A. salmonicida infection in rainbow trout. We utilized in silico screening of the proteome of A. salmonicida subsp. salmonicida strain A449 and identified potential protective protein antigens that were tested by in vivo challenge trial. A total of 14 proteins were recombinantly expressed in Escherichia coli and prepared in 3 different subunit vaccine combinations to immunize 3 groups of rainbow trout by intraperitoneal (i.p.) injection. The fish were exposed to virulent A. salmonicida 7 weeks after immunization. To assess the efficacy of the subunit vaccines we evaluated the immune response in fish after immunization and challenge infection by measuring the antibody levels and monitoring the survival of fish in different groups. The survival of fish at 3 weeks after challenge infection showed that all 3 groups of fish immunized with 3 different protein combinations exhibited significantly lower mortalities (17–30%) compared to the control groups (48% and 56%). The ELISA results revealed significantly elevated antibody levels in fish against several protein antigens, which in some cases were positively correlated to the survival. PMID:28182704

  14. Production and efficacy of an Aeromonas hydrophila recombinant S-layer protein vaccine for fish.

    Science.gov (United States)

    Poobalane, Saravanane; Thompson, Kim D; Ardó, László; Verjan, Noel; Han, Hyun-Ja; Jeney, Galina; Hirono, Ikuo; Aoki, Takashi; Adams, Alexandra

    2010-04-30

    A recombinant protein for the S-layer protein of Aeromonas hydrophila was produced and its ability to protect common carp Cyprinus carpio L. against six virulent isolates of A. hydrophila was assessed. A group of 120 carp (30-40 g) were vaccinated intra-peritoneally with 0.1 ml of adjuvanted vaccine (30 microg protein per fish). Another group of 120 carp were injected with 0.1 ml of PBS-adjuvant mixture to serve as controls. Twenty fish from each group were challenged with each one of six virulent isolates of A. hydrophila 35 days post-vaccination. The fish were maintained in 12 separate tanks before terminating the experiment at 16 days post-challenge. The relative percentage survival (RPS) for the six isolates of A. hydrophila ranged from 56 to 87%. The difference in survival rate of fish challenged with four of the isolates was statistically significant in vaccinated fish compared to control fish, when analysed using a Chi-square test. The results of the study suggest that the recombinant S-layer protein of A. hydrophila could be useful as a vaccine antigen to protect fish against different isolates of this pathogenic bacterium.

  15. Antimicrobial Susceptibility and Characterization of Outer Membrane Proteins of Aeromonas hydrophila Isolated in China

    Institute of Scientific and Technical Information of China (English)

    GUO Peng; WANG Na; LIU Yong-jie; LU Cheng-ping

    2014-01-01

    Aeromonas hydrophila isolates from clinical cases (n=43) were tested against 8 antimicrobial agents and typed by outer membrane protein (OMP) pattern by using sodium dodecyl sulfate gel electrophoresis. All isolates were resistant to ampicillin (MICs, 16 mg mL-1) and sulfamonomethoxine (MICs, 64 mg mL-1), but susceptible to norlfoxacin (MICs, 0.5 mg mL-1). There was a high incidence of resistance to erythromycin (90.70%) and tylosin (93.02%), while a low incidences of resistance to ciprofloxacin (2.33%), enrofloxacin (2.33%) and florfenicol (4.65%). Six different outer membrane protein patterns were found among 34 isolates by analyzing proteins in the range of 22 to 50 kDa, other than 9 isolates with their respective proifles. The strains with the similar OMP proifles had similar resistances. Compared with the other strains from the same OMP patterns, NB-1, A.Pun and MR-1 had lacked the proteins in the range of 30 to 45 kDa and their resistance to lforfenicol substantially increased. It is speculated that the outer membrane protein changes might correlate with decreased susceptibility to lforfenicol in the three strains. Some strains which showed completely identical OMP types had a little difference in their resistance to lfuoroquinolones, indicating that there might be other factors that were involved in the antimicrobial resistance of A. hydrophila.

  16. Proteomic Analysis Reveals That Metabolic Flows Affect the Susceptibility of Aeromonas hydrophila to Antibiotics

    Science.gov (United States)

    Yao, Zujie; Li, Wanxin; Lin, Yi; Wu, Qian; Yu, Feifei; Lin, Wenxiong; Lin, Xiangmin

    2016-01-01

    The overuse of antibiotics results in the development of antibiotic resistance and limits the useful life of these drugs in fighting bacteria, including Aeromonas hydrophila, a well-known opportunistic pathogen that causes serious infections in fish and other animals. In this study, we investigated the adaptive resistance mechanism in A. hydrophila by multiple proteomic methods. Dimethyl labeling and label-free methods were performed to compare the differential expression of proteins in response to various doses of oxytetracycline (OXY). The results point to the conclusions that, in response to OXY stress, translational processes increase the abundance of these proteins whereas largely central metabolic pathways decrease their abundance. To confirm our hypothesis, various exogenous metabolites were compounded with OXY, and the resulting survival capabilities were measured. Results show that 7 metabolites (malic acid, serine, methionine, etc.) significantly decreased the survival capabilities of A. hydrophila in the presence of OXY, whereas 4 metabolites (arginine, lysine, tyrosine, etc.) did the opposite. Further investigation suggests that a compound comprising exogenous metabolites in combination with various antibiotics could have a significant bactericidal effect and might come into widespread use, especially together with tetracycline antibiotics. These findings may provide new clues to the antimicrobial treatment of A. hydrophila infection. PMID:27991550

  17. Structural Insights on PHA Binding Protein PhaP from Aeromonas hydrophila

    Science.gov (United States)

    Zhao, Hongyu; Wei, Hui; Liu, Xi; Yao, Zhenyu; Xu, Manyu; Wei, Daixu; Wang, Jiawei; Wang, Xinquan; Chen, Guo-Qiang

    2016-01-01

    Phasins or PhaPs are a group of amphiphilic proteins that are found attached to the surface of microbial polyhydroxyalkanoate (PHA) granules. They have both structural and regulatory functions and can affect intracellular PHA accumulation and mediate protein folding. The molecular basis for the diverse functions of the PhaPs has not been fully understood due to the lack of the structural knowledge. Here we report the structural and biochemical studies of the PhaP cloned from Aeromonas hydrophila (PhaPAh), which is utilized in protein and tissue engineering. The crystal structure of PhaPAh was revealed to be a tetramer with 8 α-helices adopting a coiled-coil structure. Each monomer has a hydrophobic and a hydrophilic surface, rendering the surfactant properties of the PhaPAh monomer. Based on the crystal structure, we predicted three key amino acid residues and obtained mutants with enhanced stability and improved emulsification properties. The first PhaP crystal structure, as reported in this study, is an important step towards a mechanistic understanding of how PHA is formed in vivo and why PhaP has such unique surfactant properties. At the same time, it will facilitate the study of other PhaP members that may have significant biotechnological potential as bio-surfactants and amphipathic coatings. PMID:28009010

  18. An experimental vaccine against Aeromonas hydrophila can induce protection in rainbow trout, Oncorhynchus mykiss (Walbaum)

    Science.gov (United States)

    LaPatra, S.E.; Plant, K.P.; Alcorn, S.; Ostland, V.; Winton, J.

    2010-01-01

    A candidate vaccine against Aeromonas hydrophila in rainbow trout, Oncorhynchus mykiss, was developed using a bacterial lysate. To test the strength of protection, A. hydrophila challenge models were compared using injection into both the intraperitoneal (IP) cavity and the dorsal sinus (DS) with selected doses of live bacteria washed in saline or left untreated. Unlike the IP route, injection into the DS with either saline washed or unwashed cells resulted in consistent cumulative mortality and a dose response that could be used to establish a standard challenge having an LD50 of approximately 3 × 107 colony forming units per fish. Survivors of the challenge suffered significantly lower mortality upon re-challenge than naïve fish, suggesting a high level of acquired resistance was elicited by infection. Passive immunization using serum from hyper-immunized fish also resulted in significantly reduced mortality indicating protection can be transferred and that some portion of resistance may be antibody mediated. Vaccination of groups of rainbow trout with A. hydrophila lysate resulted in significant protection against a high challenge dose but only when injected along with Freund’s complete adjuvant. At a low challenge dose, mortality in all groups was low, but the bacterial lysate alone appeared to offer some protection.

  19. Non-specific immune response of bullfrog Rana catesbeiana to intraperitoneal injection of bacterium Aeromonas hydrophila

    Science.gov (United States)

    Zhang, Junjie; Zou, Wenzheng; Yan, Qingpi

    2008-08-01

    Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups. Each bullfrog in bacterium-injected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml, while each one in control group injected i.p. with 0.2 ml sterile saline solution (0.85%, w/v). Three bullfrogs in both groups were sampled at 0, 1, 3, 7, 11, 15 and 20 days post-injection (dpi) for the evaluation of non-specific immune parameters. It was observed that intraperitoneal injection of A. hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood. Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group. However, a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes. No significant difference in changes in the number of peripheral erythrocytes, serum superoxide dismutase (SOD) activity, and lysozyme activity was detected between the two groups. It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A. hydrophila infection.

  20. The LBP Gene and Its Association with Resistance to Aeromonas hydrophila in Tilapia

    Directory of Open Access Journals (Sweden)

    Gui Hong Fu

    2014-12-01

    Full Text Available Resistance to pathogens is important for the sustainability and profitability of food fish production. In immune-related genes, the lipopolysaccharide-binding protein (LBP gene is an important mediator of the inflammatory reaction. We analyzed the cDNA and genomic structure of the LBP gene in tilapia. The full-length cDNA (1901 bp of the gene contained a 1416 bp open reading frame, encoding 471 amino acid residues. Its genomic sequence was 5577 bp, comprising 15 exons and 14 introns. Under normal conditions, the gene was constitutively expressed in all examined tissues. The highest expression was detected in intestine and kidney. We examined the responses of the gene to challenges with two bacterial pathogens Streptcoccus agalactiae and Aeromonas hydrophila. The gene was significantly upregulated in kidney and spleen post-infection with S. agalactiae and A. hydrophila, respectively. However, the expression profiles of the gene after the challenge with the two pathogens were different. Furthermore, we identified three SNPs in the gene. There were significant associations (p < 0.05 of two of the three SNPs with the resistance to A. hydrophila, but not with the resistance to S. agalactiae or growth performance. These results suggest that the LBP gene is involved in the acute-phase immunologic response to the bacterial infections, and the responses to the two bacterial pathogens are different. The two SNPs associated with the resistance to A. hydrophila may be useful in the selection of tilapia resistant to A. hydrophila.

  1. Reduction of Aeromonas hidrophyla biofilm on stainless stell surface by essential oils

    Directory of Open Access Journals (Sweden)

    Alessandra Farias Millezi

    2013-01-01

    Full Text Available This study demonstrates the possibility of using sanitizing detergents based on natural products for the elimination and/or reduction of Aeromonas hydrophila biofilm formed on stainless steel surfaces. The goal of this work was to determine the reduction effect of sanitizing detergents containing essential oils of Thymus vulgaris (thyme and Cymbopogon citratus (lemongrass on biofilm formed by A. hydrophila on AISI 304 stainless steel coupons, using UHT skimmed milk as substratum. There was adhesion and biofilm formation by A. hydrophila at 28 ºC, presenting 7.60 log cfu.cm-2 after the fourth day of cultivation. There was no significant difference between the lemongrass treatment and that of the thyme oil (p 0.05. The treatment with lemongrass solution reduced the biofilm by 4.51 log cfu cm-2 at 25 ºC. The thyme detergent also reduced the number of cfu cm-2 by 3.84 log cycles at 25 ºC. The use of the lemongrass and thyme solutions efficiently reduced the A. hydrophila biofilm.

  2. Detection of multidrug resistance Aeromonas hydrophila in farm raised fresh water prawns

    Directory of Open Access Journals (Sweden)

    Md. Bakhtiar Lijon

    2015-12-01

    Full Text Available This study was undertaken for isolation, identification and determination of antibiogram profile of Aeromonas hydrophila in farm raised fresh water prawn (Macrobrachium rosenbergii on five commercial ghers. Fresh water prawns (n=25 were collected from five ghers located at Satkhira, Bagerhat and Khulna districts of Bangladesh. Brain (n=25, muscle (n=25 and intestine (n=25 samples were collected aseptically from fresh water prawn and inoculated into alkaline peptone (APW water for enrichment at 37℃ for 8 h. Enriched cultured was streaked into Thiosulfate Citrate Bile Salt Sucrose (TCBS agar to isolate bacteria. Bacteria were identified by cultural, Gram staining, biochemical properties and polymerase chain reaction (PCR assay. The antibiogram profiles of bacteria were investigated against 5 commonly used antibiotics (Gentamicin, Cefalexin, Ampicillin, Azithromycin and Ciprofloxacin by disc diffusion method. Thirteen A. hydrophila isolates were identified and the prevalence of the A. hydrophila in fresh water prawn was 17.33%. All 13 (100% isolates were sensitive to Ciprofloxacin, Gentamicin, Azithromycin and resistant to Ampicillin and Cefalexin. The results of this study indicate that farm raised fresh water prawn harbor multidrug resistant A. hydrophila which might causes public health problem if enter into human food chain.

  3. Anti-biofouling property of vanillin on Aeromonas hydrophila initial biofilm on various membrane surfaces.

    Science.gov (United States)

    Ponnusamy, K; Kappachery, S; Thekeettle, M; Song, J H; Kweon, J H

    2013-09-01

    Biofouling is a serious problem on filter membranes of water purification systems due to formation of bacterial biofilms, which can be detrimental to the membrane performance. Biofouling occurs on membrane surface and therefore greatly influences the physical and chemical aspects of the surface. Several membranes including microfiltration, ultrafiltration, and reverse osmosis (RO) membranes were used to learn about the anti-biofouling properties of vanillin affecting the membrane performances. Vanillin has been recognized as a potential quorum quenching compound for Aeromonas hydrophila biofilms. The initial attachment and dynamics of biofilm growth were monitored using scanning electron microscopy and confocal laser scanning microscopy. Biofilm quantities were measured using a plate count method and total protein determinations. Vanillin addition was effective in the prevention of biofilm formation on the tested membrane surfaces. Among the membranes, RO membranes made with cellulose acetate showed the most substantial reduction of biofilm formation by addition of vanillin. The biofilm reduction was confirmed by the results of surface coverage, biomass and protein accumulation. The HPLC spectrum of the spent culture with vanillin addition showed that vanillin may interfere with quorum sensing molecules and thus prevent the formation of the biofilms.

  4. The LBP gene and its association with resistance to Aeromonas hydrophila in tilapia.

    Science.gov (United States)

    Fu, Gui Hong; Liu, Feng; Xia, Jun Hong; Yue, Gen Hua

    2014-12-01

    Resistance to pathogens is important for the sustainability and profitability of food fish production. In immune-related genes, the lipopolysaccharide-binding protein (LBP) gene is an important mediator of the inflammatory reaction. We analyzed the cDNA and genomic structure of the LBP gene in tilapia. The full-length cDNA (1901 bp) of the gene contained a 1416 bp open reading frame, encoding 471 amino acid residues. Its genomic sequence was 5577 bp, comprising 15 exons and 14 introns. Under normal conditions, the gene was constitutively expressed in all examined tissues. The highest expression was detected in intestine and kidney. We examined the responses of the gene to challenges with two bacterial pathogens Streptcoccus agalactiae and Aeromonas hydrophila. The gene was significantly upregulated in kidney and spleen post-infection with S. agalactiae and A. hydrophila, respectively. However, the expression profiles of the gene after the challenge with the two pathogens were different. Furthermore, we identified three SNPs in the gene. There were significant associations (p tilapia resistant to A. hydrophila.

  5. Cloning, sequencing and expression of the gene encoding the extracellular metalloprotease of Aeromonas caviae.

    Science.gov (United States)

    Kawakami, K; Toma, C; Honma, Y

    2000-01-01

    A gene (apk) encoding the extracellular protease of Aeromonas caviae Ae6 has been cloned and sequenced. For cloning the gene, the DNA genomic library was screened using skim milk LB agar. One clone harboring plasmid pKK3 was selected for sequencing. Nucleotide sequencing of the 3.5 kb region of pKK3 revealed a single open reading frame (ORF) of 1,785 bp encoding 595 amino acids. The deduced polypeptide contained a putative 16-amino acid signal peptide followed by a large propeptide. The N-terminal amino acid sequence of purified recombinant protein (APK) was consistent with the DNA sequence. This result suggested a mature protein of 412 amino acids with a molecular mass of 44 kDa. However, the molecular mass of purified recombinant APK revealed 34 kDa by SDS-PAGE, suggesting that further processing at the C-terminal region took place. The 2 motifs of zinc binding sites deduced are highly conserved in the APK as well as in other zinc metalloproteases including Vibrio proteolyticus neutral protease, Emp V from Vibrio vulnificus, HA/P from Vibrio cholerae, and Pseudomonas aeruginosa elastase. Proteolytic activity was inhibited by EDTA, Zincov, 1,10-phenanthroline and tetraethylenepentamine while unaffected by the other inhibitors tested. The protease showed maximum activity at pH 7.0 and was inactivated by heating at 80 C for 15 min. These results together suggest that APK belongs to the thermolysin family of metalloendopeptidases.

  6. Optimization of a plasmid electroporation protocol for Aeromonas salmonicida subsp. salmonicida.

    Science.gov (United States)

    Dallaire-Dufresne, Stéphanie; Emond-Rheault, Jean-Guillaume; Attéré, Sabrina A; Tanaka, Katherine H; Trudel, Mélanie V; Frenette, Michel; Charette, Steve J

    2014-03-01

    Aeromonas salmonicida subsp. salmonicida is a major fish pathogen. Molecular tools are required to study the virulence and genomic stability of this bacterium. An efficient electroporation-mediated transformation protocol for A. salmonicida subsp. salmonicida would make genetic studies faster and easier. In the present study, we designed the 4.1-kb pSDD1 plasmid as a tool for optimizing an electroporation protocol for A. salmonicida subsp. salmonicida. We systematically tested the electroporation conditions to develop a protocol that generates the maximum number of transformants. Under these optimal conditions (25 kV/cm, 200 Ω, 25 μF), we achieved an electroporation efficiency of up to 1×10(5) CFU/μg DNA. The electroporation protocol was also tested using another plasmid of 10.6-kb and three different strains of A. salmonicida subsp. salmonicida. The strains displayed significant differences in their electro-transformation competencies. Strain 01-B526 was the easiest to electroporate, especially with the pSDD1 plasmid. This plasmid was stably maintained in the 01-B526 transformants, as were the native plasmids, but could be easily cured by removing the selection conditions. This is the first efficient electroporation protocol reported for A. salmonicida subsp. salmonicida, and offers new possibilities for studying this bacterium.

  7. Inactivation of Pseudomonas aeruginosa and Aeromonas hydrophila by silver in tap water.

    Science.gov (United States)

    Silvestry-Rodriguez, Nadia; Bright, Kelly R; Uhlmann, Donald R; Slack, Donald C; Gerba, Charles P

    2007-09-01

    This study was conducted to assess the efficacy of silver as a secondary disinfectant to replace or reduce the level of chlorine utilized in water distribution systems. Pseudomonas aeruginosa and Aeromonas hydrophila are opportunistic pathogens present in drinking water and have been associated with waterborne disease. After 8 hours of exposure to 100 microg/L of silver, there was a >6-log10 reduction in P. aeruginosa in tap water at room temperature at pH7 and a 5.55-log10 reduction in the presence of 3 mg/L humic acid. Similar reductions were observed at pH9. At 4 degrees C, reductions greater than 4-log10 were observed after 24 hours. For A. hydrophila, a >6-log10 reduction occurred at both pH7 and pH9 within nine hours. The World Health Organization has determined that this amount of silver could be used for water disinfection without health risks. Furthermore, silver shows promise as a secondary disinfectant, even in the presence of organic matter in concentrations that would reduce the effectiveness of free chlorine.

  8. Growth inhibition of Aeromonas salmonicida and Yersinia ruckeri by disinfectants containing peracetic acid.

    Science.gov (United States)

    Meinelt, Thomas; Phan, Thy-My; Behrens, Sascha; Wienke, Andreas; Pedersen, Lars-Flemming; Liu, Dibo; Straus, David L

    2015-04-08

    Peracetic acid (PAA) is a therapeutic agent used for disinfection in aquaculture, but it must be investigated thoroughly in order to mitigate diseases without harming the fish. Successful disinfectants (like PAA) should not leave dangerous residues in the environment in order to successfully contribute to sustainable aquaculture. The aim of our study was to compare the effectiveness of 6 commercial PAA products with different molecular PAA:H2O2 ratios to reduce bacterial growth of Aeromonas salmonicida and Yersinia ruckeri and to determine effective concentrations and exposure times. All products reduced colony-forming units (CFUs) of A. salmonicida and Y. ruckeri. Products with higher molecular PAA:H2O2 ratios inhibited growth better than products with lower molecular PAA:H2O2 ratios at the same PAA concentration; this indicates that H2O2 is not the driving force in the reduction of A. salmonicida and Y. ruckeri growth by PAA in vitro. The practical application of the products with high molecular PAA:H2O2 ratios should be prioritized if these pathogens are diagnosed.

  9. Surface protein composition of Aeromonas hydrophila strains virulent for fish: identification of a surface array protein

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, J.S.G.; Trust, T.J.

    1988-02-01

    The surface protein composition of members of a serogroup of Aeromonas hydrophila was examined. Immunoblotting with antiserum raised against formalinized whole cells of A. hydrophila TF7 showed a 52K S-layer protein to be the major surface protein antigen, and impermeant Sulfo-NHS-Biotin cell surface labeling showed that the 52K S-layer protein was the only protein accessible to the Sulfo-NHS-Biotin label and effectively masked underlying outer membrane (OM) proteins. In its native surface conformation the 52K S-layer protein was only weakly reactive with a lactoperoxidase /sup 125/I surface iodination procedure. A UV-induced rough lipopolysaccharide (LPS) mutant of TF7 was found to produce an intact S layer, but a deep rough LPS mutant was unable to maintain an array on the cell surface and excreted the S-layer protein into the growth medium, indicating that a minimum LPS oligosaccharide size required for A. hydrophila S-layer anchoring. The native S layer was permeable to /sup 125/I in the lactoperoxidase radiolabeling procedure, and two major OM proteins of molecular weights 30,000 and 48,000 were iodinated. The 48K species was a peptidoglycan-associated, transmembrane protein which exhibited heat-modifiable SDS solubilization behavior characteristic of a porin protein. A 50K major peptidoglycan-associated OM protein which was not radiolabeled exhibited similar SDS heat modification characteristics and possibly represents a second porin protein.

  10. Aeromonas hydrophila-associated skin lesions and septicaemia in a Nile crocodile (Crocodylus niloticus : clinical communication

    Directory of Open Access Journals (Sweden)

    H. Turutoglu

    2005-06-01

    Full Text Available Aeromonas hydrophila is one of the most common bacteria associated with the aquatic environment. There are , however, limited data on A. hydrophila infection in crocodilians. The aim of this report is to describe a case of skin lesions and septicaemia associated with A. hydrophila in a Nile crocodile (Crocodylus niloticus. A captive male crocodile in the Zoological Park of Antalya (Turkey was found dead without showing signs of any disease. Gross examination showed brown or red-spotted skin lesions of varying size. These lesions were mostly scattered over the abdomen and occasionally on the tail and feet. At necropsy, numerous white, multifocal and randomly distributed areas were seen on the liver. Gram-stained smears from skin and liver lesions showed Gram-negative bacilli arranged in clusters. Pure cultures of A. hydrophila were recovered from skin, internal organs and blood. Isolates were found to be susceptible to ceftiofur, amoxicillin + clavulanic acid, oxytetracycline, enrofloxacin, danofloxacin, neomycin, gentamicin, and lincomycin + neomycin. A pathogenicity test was performed using this isolate on 4 male 2-year-old New Zealand white rabbits. Local abscesses formed in 2 rabbits injected subcutaneously and the 2 that were injected intraperitoneally died as a result of septicaemia. In conclusion, this report has shown that A. hydrophila may cause skin lesions and even death due to septicaemia in crocodiles.

  11. PROBIOTIK Bacillus firmus UNTUK PENGENDALIAN PENYAKIT Aeromonas hydrophila PADA BUDIDAYA IKAN LELE DUMBO, Clarias gariepinus

    Directory of Open Access Journals (Sweden)

    Angela Mariana Lusiastuti

    2013-08-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui efektivitas pemberian bakteri probiotik Bacillus firmus terhadap ketahanan benih ikan lele dumbo (Clarias gariepinus yang diinfeksi Aeromonas hydrophila. Probiotik diberikan melalui media budidaya dengan Rancangan Acak Lengkap (RAL menggunakan lima perlakuan dan tiga ulangan yang diaplikasikan untuk pengendalian penyakit motile aromonas septicemia (MAS. Perlakuan tersebut adalah A (tanpa penambahan bakteri probiotik B. firmus (sebagai control, B (penambahan bakteri probiotik B. firmus 105 cfu/mL, C (penambahan bakteri probiotik B. firmus 107 cfu/mL, D (penambahan bakteri probiotik B. firmus 109 cfu/mL, dan E (penambahan bakteri probiotik B. firmus 1011 cfu/mL. Pengamatan meliputi tingkat sintasan ikan uji setelah diuji tantang dengan A. hydrophila, indeks fagositik, diferensial leukosit dan kualitas air. Analisis data tingkat sintasan dilakukan dengan menggunakan uji F dengan taraf signifikansi 5%. Indeks fagositik, differensial leukosit dan kualitas air dianalisis secara deskriptif. Hasil penelitian menunjukkan bahwa sintasan tertinggi setelah diinfeksi A. hydrophila terdapat pada perlakuan D (109 cfu/mL yaitu 53,33% dan adanya peningkatan kadar limfosit sebesar 81% serta aktivitas fagosit sebesar 60% setelah penambahan bakteri probiotik B. firmus. Sementara hasil terendah terdapat pada perlakuan A (kontrol (tanpa penambahan bakteri probiotik sebesar 8,33%, aktivitas fagosit sebesar 60% setelah pemeliharaan ikan uji selama 14 hari.

  12. Two membrane filter media (mADA/0129 and mSA/0129 agars) for enumeration of motile Aeromonas in seawater.

    Science.gov (United States)

    Alonso, J L; Garay, E

    1989-10-01

    Sewage-contaminated natural seawater was analysed for the presence of motile Aeromonas by two membrane filtration procedures. Incubation of membranes on two modified media (mADA (0/129) and mSA (0/129) were compared. The specificity of the two media was high, 95.8% on mADA (0/129) and 94.8% on mSA (0129). The most frequent species identified were A. caviae, followed by A. hydrophila and A. sobria. Motile Aeromonas counts were high in both media (greater than 10(4)/100 ml) and no significant differences were observed between them. The two membrane filtration procedures allowed rapid quantitative recovery of motile Aeromonas from seawater in the presence of very large numbers of competing microflora.

  13. Diverse Profiles of N-acyl Homoserine L-Lactones, Biofilm, Virulence Genes and Integrons in Food-Borne Aeromonas Isolates.

    Science.gov (United States)

    Nagar, Vandan; Sinha, Vibha; Bandekar, Jayant R

    2015-08-01

    Aeromonas are regarded as opportunistic as well as primary pathogens of humans and fish, and are associated with gastroenteritis and septicemia in humans. Production of N-acyl-homoserine lactone (AHL) signal molecules and biofilm was determined in 22 Aeromonas isolates, from different food products in India, using thin-layer chromatography (TLC) analysis and microtiter-plate assay, respectively. Overall, highly heterogeneous patterns of AHL production were observed, with the production of N-butanoyl homoserine lactone (C4-HSL) and N-hexanoyl homoserine lactone (C6-HSL) by the majority (81.8%) of Aeromonas food isolates. Moreover, putative N-pentanoyl homoserine lactone (C5-HSL), N-heptanoyl homoserine lactone (C7-HSL), and N-octanoyl homoserine lactone (C8-HSL) were produced by 72.7%, 27.3%, and 9.1% of isolates, respectively. This is the 1st report of production of C7-HSL by Aeromonas species. Aeromonas food isolates were highly variable in their biofilm forming abilities with majority of them as weak biofilm producers in 2 different media, TSB and M9 minimal medium supplemented with 0.4% glucose. The genes encoding for putative virulence factors, glycerophospholipid cholesterol acyltransferase (gcat), heat-labile cytotonic enterotoxin (alt), heat-stable cytotonic enterotoxin (ast), serine protease (ser), polar flagella (fla), and lateral flagella (lafA) were present in 95.5%, 59.1%, 22.7%, 81.8%, 77.3%, and 22.7% of the strains, respectively. Class 1 integrons (100 to 3000 bp) were found in 68.2% of food isolates; whereas, 50% isolates contained class 2 integrons (150 to 1600 bp). This study provides a baseline data on the diversity of AHLs, biofilm forming ability and presence of virulence genes and integrons in Aeromonas food isolates from India.

  14. Aeromonas spp. and microbial indicators in raw drinking water source Aeromonas sp. e indicadores microbiológicos em fontes de água não tratada

    Directory of Open Access Journals (Sweden)

    Marisa Di Bari

    2007-09-01

    Full Text Available Aeromonas species are autochtonous in the aquatic environment and some of them have been associated with health effects like wound infections, septicemia and diarrhoeal illness. In this study, the occurrence of Aeromonas spp. and microbial indicators in raw drinking water from wells, springs, fountains and mineral waters was evaluated. A total of 126 water samples was analyzed for Aeromonas spp. by the membrane filtration technique using ADA media and by P/A test. Typical colonies of Aeromonas spp. were submitted to biochemical tests for species differentiation. Toxin production was tested using Y-1 mouse adrenal cells. Coliforms and heterotrophic bacteria were enumerated by membrane filtration and pour plate techniques, respectively. P. aeruginosa, C. perfringens and fecal streptococci were determined by P/A method. Aeromonas spp. were isolated in 36.5% of the samples, whereas total and thermotolerant coliforms were detected in 51.2% and in 23.8% of the samples, respectively. C. perfringens, fecal streptococci and P. aeruginosa were present in 16.5%, 20.4% and 3.8% of the samples, respectively. The concentrations of heterotrophic bacteria were higher than 1,0x10³ CFU/mL in 52.5% of the samples. A. hydrophila was the most frequent species, followed by A. allosaccharophila,A. jandaei,A.sobria and HG2. A heat label toxin was detected in 13 from the 58 strains tested. These data show that the drinking water sources analyzed can represent a risk for human health. It is important to consider that wells and springs are used as drinking water supply in poor areas and rural regions, where undernourished people more susceptible to infections by these microorganisms predominate.Bactérias do gênero Aeromonas são naturais no ambiente aquático e algumas espécies podem causar infecções em humanos como feridas, septicemia e diarréia. Este trabalho objetivou avaliar a ocorrência de Aeromonas sp. em 126 amostras de água de poços, nascentes, fontes e

  15. Aeromonas hydrophila infection in Estuarine crocodile from Thailand%泰国湾鳄嗜水气单胞菌感染

    Institute of Scientific and Technical Information of China (English)

    李明杰; 王志国

    2003-01-01

    @@ 气单胞菌属(Aeromonas)中嗜水气单胞菌(Aeromonas hy-drophila)是两栖爬行动物中最常见的机会致病菌.嗜水气单胞菌在水体环境中广泛分布,能使水生动物、水禽发病.现在越来越多的报道表明,嗜水气单胞菌亦能感染东北虎、北极熊、猪、兔等哺乳动物及人类.

  16. Characterization and virulence potential of phenotypically diverse Aeromonas veronii isolates recovered from moribund freshwater ornamental fishes of Kerala, India.

    Science.gov (United States)

    Sreedharan, Krishnan; Philip, Rosamma; Singh, Isaac Sarojani Bright

    2013-01-01

    In the present study, we investigated the involvement of Aeromonas spp. in eliciting disease outbreaks in freshwater ornamental fishes across the state of Kerala, India. We investigated three incidences of disease, in which the moribund fishes exhibited clinical signs such as haemorrhagic septicemia (in gouramy, Trichogaster sp.), dropsy (in Oscar, Astronotus ocellatus) and tail rot/fin rot (in gold fish, Carassius carassius). Pure cultures (n = 20 from each fish; 60 in total) of Aeromonas spp. were recovered from the abdominal fluid as well as from internal organs of affected fishes, although they could not be identified to species level because of the variations in their phenotypic characters. The molecular fingerprinting of the isolates using Enterobacterial Repetitive Intergenic Consensus PCR proved the genetic diversity of the isolates from the three sites. The phylogenetic trees constructed using concatenated sequences (using 16S rRNA, gyrA, gyrB and rpoD genes) indicated that they were related to Aeromonas veronii. They exhibited marked cytotoxic and haemolytic activity, which were responsible for the pathogenic potential of the isolates. The isolates possessed multiple virulence genes such as enterotoxins (act and alt), haemolytic toxins (aerA and hlyA), genes involved in type III secretion system (ascV, aexT and ascF-ascG), glycerophospholipid-cholesterol acyltransferase (gcat) and a type IV pilus (tapA) gene, as determined by PCR. Virulence of representative isolates to goldfish was also tested, and we found LD(50) values of 10(4.07)-10(5.35) cfu/fish. Furthermore, the organisms could be recovered as pure cultures from the lesions as well as from the internal organs.

  17. Melanization and pathogenicity in the insect, Tenebrio molitor, and the crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3.

    Directory of Open Access Journals (Sweden)

    Chadanat Noonin

    Full Text Available Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS, bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish and Tenebrio molitor larvae (mealworm. The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the

  18. Melanization and pathogenicity in the insect, Tenebrio molitor, and the crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3.

    Science.gov (United States)

    Noonin, Chadanat; Jiravanichpaisal, Pikul; Söderhäll, Irene; Merino, Susana; Tomás, Juan M; Söderhäll, Kenneth

    2010-12-29

    Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS), bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish) and Tenebrio molitor larvae (mealworm). The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core) is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT) containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the proPO system

  19. Resistencia a antibioticos y presencia de plasmidos en: Aeromonas hydrophila, Vibrio fluvialis y Vibrio furnissii, aislados de Carassius auratus auratus

    OpenAIRE

    Pilar Negrete Redondo; Jorge Romero Jarero; José Luis Arredondo Figueroa

    2004-01-01

    Se aislaron e identificaron 70 cepas bacterianas del riñón de peces de ornato Carassius auratus con signos y lesiones de infección. Las especies bacterianas aisladas e identificadas, Aeromonas hydrophila, Vibrio fluvialis y Vibrio furnissii, han sido descritas como causantes de diarrea en humano y como patógeno muy agresivo en cultivos de Ciprinus carpio. Por esta razón se ha hecho mal uso y abuso de antibióticos para evitar y controlar la presencia de esta bacteria en los cultivos. El uso fu...

  20. Characterisation of potential virulence markers in Aeromonas caviae isolated from polluted and unpolluted aquatic environments in Morocco

    DEFF Research Database (Denmark)

    Imziln, Boujama; Krovacek, Karel; Baloda, Suraj B.

    1998-01-01

    .406) than those isolated from raw sewage (PVI = 0.175) or those from river waters (PVI = 0.09). These results suggest that stabilisation pond systems used for sewage purification under arid climate conditions in Marrakech, may have selected potentially enteropathogenic A. caviae strains.......A total of 100 Aeromonas caviae strains isolated from river waters (38 isolates), raw sewage (30 isolates) and effluents of stabilisation ponds (i.e. treated sewage; 32 isolates) in Marrakech, Morocco, were tested for the presence of putative virulence factors to delineate differences, if any...

  1. Characterization of class 1 integrons associated with R-plasmids in clinical Aeromonas salmonicida isolates from various geographical areas

    DEFF Research Database (Denmark)

    Schmidt, A.S.; Bruun, Morten Sichlau; Larsen, J.L.;

    2001-01-01

    Class 1 integrons were found in 26 of 40 antibiotic-resistant isolates of the fish pathogen Aeromonas salmonicida from Northern Europe and North America. Three different dhfr genes, conferring trimethoprim resistance, and one ant(3 " )1a aminoglycoside resistance gene were identified as gene...... inserts. The gene cassettes tended to be conserved among isolates from a particular geographical area. Nineteen isolates transferred R- plasmids carrying different tet determinants to Escherichia coli in filter mating assays, and in 15 cases, the class 1 integrons were co-transferred. Transferable...

  2. PARTICIPACION DEL COMPLEJO PIRUVATO DESHIDROGENASA DE AEROMONAS CAVIAE ST EN RESISTENCIA TELURITO DE POSTASIO (K2TEO3)

    OpenAIRE

    2008-01-01

    El telurito de potasio (K2TeO3) es altamente tóxico para la mayoría de los seres vivos. Aunque se desconoce el mecanismo de toxicidad especifico, recientemente se ha demostrado que estaría dado, al menos en parte, por el establecimiento de un estrés oxidativo. Aeromonas caviae ST, el microorganismo utilizado en este estudio es altamente resistente a K2TeO3 y extractos crudos de esta bacteria catalizan la reducción de K2TeO3 in vitro. Se obtuvo fracciones con actividad telurito reductasa qu...

  3. Effect of electron irradiation and packaging atmosphere on the survival of Aeromonas hydrophila in minced poultry meat

    Energy Technology Data Exchange (ETDEWEB)

    Stecchini, M.L.; Sarais, I.; Del Torre, M. [Dipartimento di Scienze degli Alimenti, Udine (Italy); Fuochi, P.G. [Istituto FRAE-CNR, Bologna (Italy)

    1995-10-01

    Resistance to electron irradiation of Aeromonas hydrophila inoculated in minced poultry meat packed in presence of air or under vacuum was examined. Surviving bacteria were counted on starch ampicillin agar containing 100 {mu}g/ml of ampicillin. Radiation resistance, expressed as D{sub 10} values, was calculated from the survival curves and found to be 0.12 and 0.14 kGy in poultry meat packed in air or under vacuum respectively. Storage at 2{sup o}C of meat samples irradiated at 0.5 kGy further reduced the number of A. hydrophila. (Author).

  4. Effect of electron irradiation and packaging atmosphere on the survival of aeromonas hydrophila in minced poultry meat

    Science.gov (United States)

    Stecchini, M. L.; Sarais, I.; Del Torre, M.; Fuochi, P. G.

    1995-02-01

    Resistance to electron irradiation of Aeromonas hydrophila inoculated in minced poultry meat packed in presence of air or under vacuum was examined. Surviving bacteria were counted on starch ampicillin agar containing 100 μg/ml of ampicillin. Radiation resistance, expressed as D 10 values, was calculated from the survival curves and found to be 0.12 and 0.12 kGy in poultry meat packed in air or under vacuum respectively. Storage at 2°C of meat samples irradiated at 0.5 kGy further reduced the number of A. hydrophila.

  5. Biochemical characteristics, serogroups, and virulence factors of aeromonas species isolated from cases of diarrhoea and domestic water samples in Chennai

    Directory of Open Access Journals (Sweden)

    Alavandi S

    2003-01-01

    Full Text Available PURPOSE: The objective of the present study was to delineate the differences between the clinical and environmental Aeromonas species with respect to their biochemical characteristics, serogrouping and virulence factors, in order to find a phenotypic marker of enteropathogenicity. METHODS: A total of 55 Aeromonas spp. inclusive of 19 isolates from cases of diarrhoea, and 36 from water samples comprising, 10 isolates of A. hydrophila, 21 isolates each of A. sobria, and A. caviae, two isolates of A. jandaei and one isolate of A. veronii were subjected to analysis of their biochemical characteristics, serogrouping, and virulence factors. RESULTS: Among the differences recorded in the biochemical characteristics in the three major species, the most striking characteristic was fermentation of lactose, which was observed in all the 11 A. caviae isolates recovered from water samples. None of the 10 clinical isolates of A. caviae tested fermented lactose. The clinical Aeromonas isolates belonged to seven typable serogroups, O:13, O:14, O:16, O:21, O:27, O:32 and O:35. The environmental isolates belonged to eight different serogroups, such as, O:3, O:11, O:14, O:16, O:18, O:28, O:64 and O:78 and were predominated by serotypes O:18 and O:64. Among the virulence factors tested, 89% of the environmental isolates produced b haemolysin, while only 62.3% of clinical isolates were able to do so. There was no significant difference between the clinical and environmental aeromonads with respect to their enterotoxigenicity in suckling mice in vivo, cytotoxicity in vitro in Vero cell monolayers, and ability to produce siderophores. CONCLUSION: Efforts to delineate the differences between the clinical and environmental Aeromonas spp. did not reveal significant difference between them. However, difference was observed with respect to their ability to produce b haemolysin, wherein, higher percentage of environmental isolates was haemolytic. The results also suggest

  6. An Aeromonas caviae Genomic Island Is Required for both O-Antigen Lipopolysaccharide Biosynthesis and Flagellin Glycosylation ▿

    OpenAIRE

    Tabei, S. Mohammed B.; Hitchen, Paul G.; Day-Williams, Michaela J.; Merino, Susana; Vart, Richard; Pang, Poh-Choo; Horsburgh, Gavin J.; Viches, Silvia; Wilhelms, Markus; Tomás, Juan M.; Dell, Anne; Shaw, Jonathan G

    2009-01-01

    Aeromonas caviae Sch3N possesses a small genomic island that is involved in both flagellin glycosylation and lipopolysaccharide (LPS) O-antigen biosynthesis. This island appears to have been laterally acquired as it is flanked by insertion element-like sequences and has a much lower G+C content than the average aeromonad G+C content. Most of the gene products encoded by the island are orthologues of proteins that have been shown to be involved in pseudaminic acid biosynthesis and flagellin gl...

  7. Determinación de factores de virulencia en cepas de Aeromonas spp., aisladas a partir de pescado

    OpenAIRE

    William Suárez Q.; Fanny Herrera A.

    2012-01-01

    RESUMENObjetivo. Investigar la incidencia de cinco marcadores fenotípicos de virulencia en cepas de Aeromonas aisladas a partir de muestras de pescado expendido en Pamplona, Colombia. Materiales y métodos. Se utilizaron 47 cepas identificadas previamente. Se evaluaron: actividad hemolítica en agar sangre, suplementado con 5% de eritrocitos de cordero y agar sangre suplementado con 5% eritrocitos de sangre humana; actividad proteolítica en agar Mueller-Hinton suplementado al 10% (p/v) con lech...

  8. The genome of Aeromonas salmonicida subsp. salmonicida A449: insights into the evolution of a fish pathogen

    Directory of Open Access Journals (Sweden)

    Murphy Colleen

    2008-09-01

    Full Text Available Abstract Background Aeromonas salmonicida subsp. salmonicida is a Gram-negative bacterium that is the causative agent of furunculosis, a bacterial septicaemia of salmonid fish. While other species of Aeromonas are opportunistic pathogens or are found in commensal or symbiotic relationships with animal hosts, A. salmonicida subsp. salmonicida causes disease in healthy fish. The genome sequence of A. salmonicida was determined to provide a better understanding of the virulence factors used by this pathogen to infect fish. Results The nucleotide sequences of the A. salmonicida subsp. salmonicida A449 chromosome and two large plasmids are characterized. The chromosome is 4,702,402 bp and encodes 4388 genes, while the two large plasmids are 166,749 and 155,098 bp with 178 and 164 genes, respectively. Notable features are a large inversion in the chromosome and, in one of the large plasmids, the presence of a Tn21 composite transposon containing mercury resistance genes and an In2 integron encoding genes for resistance to streptomycin/spectinomycin, quaternary ammonia compounds, sulphonamides and chloramphenicol. A large number of genes encoding potential virulence factors were identified; however, many appear to be pseudogenes since they contain insertion sequences, frameshifts or in-frame stop codons. A total of 170 pseudogenes and 88 insertion sequences (of ten different types are found in the A. salmonicida genome. Comparison with the A. hydrophila ATCC 7966T genome reveals multiple large inversions in the chromosome as well as an approximately 9% difference in gene content indicating instances of single gene or operon loss or gain. A limited number of the pseudogenes found in A. salmonicida A449 were investigated in other Aeromonas strains and species. While nearly all the pseudogenes tested are present in A. salmonicida subsp. salmonicida strains, only about 25% were found in other A. salmonicida subspecies and none were detected in other

  9. DIARRHEA OUTBREAK IN PERNAMBUCO, BRAZIL, ASSOCIATED WITH A HEAT-STABLE CYTOTOXIC ENTEROTOXIN PRODUCED BY Aeromonas caviae.

    Science.gov (United States)

    Lopes, Ana Carolina Amaral; Martins, Luciano Moura; Gatti, Maria Silvia Viccari; Falavina Dos Reis, Cristhiane Moura; Hofer, Ernesto; Yano, Tomomasa

    2015-01-01

    In the present study enterotoxic and cytotoxic activities of twenty Aeromonas caviae strains were examined. They originated from fecal specimens of patients with acute diarrhea during an outbreak in Brazil in 2004. Culture supernatants of fourteen strains (70%) caused fluid accumulation in rabbit ileal intestinal loops and in suckling mice assays, and also showed a cytotoxic activity in Vero and Caco-2 cells. The enterotoxic and cytotoxic factors were heat-stable after culture supernatants treatment at 100 ºC. The results revealed that A. caviae strains produce a putative diarrheagenic virulence factor, a heat-stable cytotoxic enterotoxin that could be linked to the diarrhea outbreak that took place in Brazil.

  10. ANTIBIOTICS RESISTANCE AND PUTATIVE VIRULENCE FACTORS OF AEROMONAS HYDROPHILA ISOLATED FROM ESTUARY

    Directory of Open Access Journals (Sweden)

    Olumide Adedokun Odeyemi

    2012-06-01

    Full Text Available This study aim to investigate antibiotics resistance profile and putative virulence factors of Aeromonas hydrophila isolated from estuary. Bacteria used for this study were isolated from water and sediment samples obtained from Sungai Melayu, Johor, Malaysia. Serially diluted 100 µL water and 1g sediment were inoculated on modified Rimler - Shott (mRS agar. Colonies with distinct cultural characteristics were picked for further studies. Isolates were tested for biofilm productions, protease enzyme and antibiotics resistance profile using agar well diffusion method against 10 commercial antibiotics. Congo Red Agar (CRA, Microplate and Standard Tube (ST methods were used for assessment of biofilm formation among the isolates while Skim Milk Agar was used for protease production. Sw.KMJ 3 and Sw.KMJ 9 produced black crystalline colonies on CRA. Six of the isolates were biofilm producers in ST method. Result of Microplate method, helped in grouping the isolates into weak (n = 8, moderate (n = 3 and strong producers (n = 4 at 540 nm wavelength. All the isolates were classified as weak ODc  ODi 0.1, moderate ODi = 0.1  0.12 and strong producers ODi  0.12 respectively at 540 nm wavelength. Antibiotics susceptibility test also revealed that all the isolates were resistant to between 6 and 10 antibiotics. Two isolates each were resistant to 6 (60 %, 7 (70 % and 9 (90 % antibiotics respectively. Eight of the isolates showed resistance to 8 (80 % antibiotics while only isolate Sw.KMJ-7 showed resistance to all the tested antibiotics. Sw.KMJ-3, Sw.KMJ-8 and Sw.KMJ-9 produced protease enzyme on SMA. The isolates were also found to be resistant to both antibiotics and heavy metals.

  11. Immunostimulatory effect of artificial feed supplemented with indigenous plants on Clarias gariepinus against Aeromonas hydrophila.

    Science.gov (United States)

    Verma, Vipin Kumar; Rani, Kumari Vandana; Sehgal, Neeta; Prakash, Om

    2013-12-01

    The antibacterial activity of methanol extracts of Ficus benghalensis (prop-root) and Leucaena leucocephala (pod seed) was evaluated by measurement of zone of inhibition against pathogenic bacteria, Escherichia coli and Aeromonas hydrophila. Control artificial feed and artificial feed supplemented with 5% powder of F. benghalensis and L. leucocephala were prepared. Juvenile Clarias gariepinus were divided into four groups, acclimatized to laboratory conditions and fed with respective feeds for 20 days prior to the experiment. Immunomodulatory response of supplementary feed was studied by challenging the fish intraperitoneally at weekly intervals, with A. hydrophila. One set of fish, not challenged with A. hydrophila was used as a negative control, to analyze any detrimental effect of supplementary feed, while positive control, comprised of challenged fish fed with non-supplemented feed. Other two groups of fish were challenged with A. hydrophila and fed with respective supplementary feeds. Blood was collected on weekly intervals for four weeks and serum samples were analyzed to evaluate the damage of fish by A. hydrophila through liver function tests. The increase in the levels of Serum glutamic oxaloacetic transaminase (SGOT) and Serum Glutamic pyruvate transaminase (SGPT) in positive control group indicated the damage of liver & kidney. However the levels did not change significantly in fish fed with supplementary feeds when compared to negative control group. Nitric oxide, SOD, ALP and lipid peroxidase indicated lower stress levels in these fish compared to positive control. Fish fed with supplementary feed showed increased lysozyme activity and phagocytic index indicating an increase in non-specific immune response. The immunoglobulin levels of in serum were analyzed by homologous sandwich ELISA, which showed higher antibody production in fish fed with supplementary feed. The current study suggests conclusively, immunostimulatory role of F. benghalensis (prop

  12. Type III secretion system of Aeromonas salmonicida undermining the host’s immune response

    Directory of Open Access Journals (Sweden)

    Joachim Frey

    2016-07-01

    Full Text Available Aeromonas salmonicida subsp. salmonicida is an important pathogen in salmonid aquaculture and is responsible for furunculosis, a common infectious disease in salmon, trout and char. The type-three secretion system (T3SS is considered as the major virulence attribute of A. salmonicida. It is used by the bacterium to secrete and translocate a large number of toxins and effector proteins into the host cell. Some of these factors such as the bi-functional ADP ribosylating – GTPase activating protein AexT have been shown to have a detrimental impact on the integrity of the cell cytoskeleton, and hence contribute to impair phagocytosis. Other effector proteins that are injected to the host cell such as AopP act by inhibiting the NF-κB signalling pathway blocking the translocation of NF-κB (p65 into the nucleus, thus influencing the host’s inflammatory response. Several additional effectors that are secreted and translocated via the T3SS including Ati2, AopN and ExsE have been suggested to modulate the host’s immune response in particular by down regulating the inflammatory reaction. The analysis of the immune response in rainbow trout (Oncorhynchus mykiss infected with virulent, T3SS harbouring A. salmonicida subsp. salmonicida revealed that the infection leads to a rapid and strong downregulation of several immune-relevant markers affecting both the innate and the adaptive immune response, leading to mortality of the infected fish. In contrast, infection with a T3SS deficient mutant causes a normal immune reaction and clearing of the pathogen. These findings show that T3SS-delivered effector molecules and toxins of A. salmonicida do not only impair the host’s cytoskeleton thus damaging cell physiology and phagocytosis, but also affect the transcription of critical immune markers including the shut-down of important warning signals to recognize infection and induce immune defense.

  13. EVALUATION OF IMMUNOSTIMULATORY POTENTIAL OF PHYLLANTHUS AMARUS IN LABEO ROHITA INFECTED WITH AEROMONAS HYDROPHILA: HAEMATOLOGICAL ASSESSMENT

    Directory of Open Access Journals (Sweden)

    T.Annalakshmi

    2013-02-01

    Full Text Available Outbreak of disease is an important limiting factor in aquaculture. Incorporation of herbal immunostimulants in diet is one of the widely followed methods to improve the general resistance in fish. The present experiment was carried out to evaluate the Immunostimulatory potential of the medicinal herb Phyllanthus amarus in fish. The experiment was carried out in two sets. In experiment-I, one group of Labeo rohita was fed with control diet (‘C’ diet and the other group was fed with Phyllanthus amarus incorporated diet (‘P’ diet for 14 days and the haematological parameters were analysed on 1st, 3rd, 7th and 14th day of the experiment. Significant increase in Total Erythrocyte Count (TEC, Haemoglobin (Hb g%, Total Leucocyte Count (TLC, lymphocytes, monocytes and neutrophils were observed in ‘P’ diet fed fishes with increase in the duration of the experiment. As there is positive response in the first experiment hence experiment-II was carried out. In experiment-II, One group of Labeo rohita were fed with ‘C’ diet and other group received ‘P’ diet for 14 days, post-infected with Aeromonas hydrophila and haematological parameters were analyzed on 1st, 3rd, 7th & 14th days after infection. Significant increase in TEC, Hb, TLC, lymphocytes and a steady population of monocytes and neutrophils were observed in ‘P’ diet fed fishes. On the other hand basophils and eosinophil count exhibited a fluctuating trend. Thus dietary incorporation of Phyllanthus amarus helps to improve the general health and resistance of the fish.

  14. Correlation between the distribution pattern of virulence genes and virulence of Aeromonas hydrophila strains

    Institute of Scientific and Technical Information of China (English)

    ZHU Daling; LI Aihua; WANG Jianguo; LI Ming; CAI Taozhen; HU Jing

    2007-01-01

    Nine strains of Aeromonas hydrophila isolated from diseased fish or soft-shelled tortoise were tested for the presence of three virulence genes including the genes encoding aerolysin,hemolysin,and extracellular serine protease (i.e.,aerA,hlyA,and ahpA,respectively).These genes were investigated using polymerase chain reaction (PCR)with specific primers for each gene.And the pathogenicities to Carrassius auratus ibebio of these strains were also assayed.PCR results demonstrated that the distribution patterns of aerA,hlyA,and ahpA were different in these strains.6/9 of A.hydrophila strains were aer A positive,8/9 of strains hly A positive,7/9 of strains ahp A positive,respectively.However,the assay for pathogenesis showed that two strains (A.hydrophila XS91-4-1 and C2)were strong virulent,two strains (A.hydrophila ST78-3-3 and 58-20-9)avirulent and the rest middle virulent was to the fish.In conclusion,there are significant correlation between the distribution pattern of the three virulence genes and the pathogenicity to Carrassius auratus ibebio.All strong virulent A.hydrophila strains were aerA+hlyA+ahpA+genotype,and all aerA+hlyA+ahpA+strains were virulent.Strains with the genotype of aerA-hlyA-ahpA+have middle pathogenicity.In the present study,we found for the first time that all A.hydrophila isolated from the ahpA positive were virulent to Carrassius auratus ibebio.Additionally,there was a positive correlation between the virulence of A.hydrophila and the presence of aerA and ahpA.

  15. Biological approach to synthesize TiO2 nanoparticles using Aeromonas hydrophila and its antibacterial activity

    Science.gov (United States)

    Jayaseelan, Chidambaram; Rahuman, Abdul Abdul; Roopan, Selvaraj Mohana; Kirthi, Arivarasan Vishnu; Venkatesan, Jayachandran; Kim, Se-Kwon; Iyappan, Moorthy; Siva, Chinnadurai

    2013-04-01

    Nanosized materials have been an important subject in basic and applied sciences. A novel, low-cost, green and reproducible bacteria, Aeromonas hydrophila mediated biosynthesis of titanium dioxide nanoparticles (TiO2 NPs) was reported. The resulting nanoparticles were characterized by FTIR, XRD, AFM and FESEM with EDX. FTIR showed characteristic bands (1643 and 3430 cm-1) finds the role of carboxyl group Osbnd H stretching amine Nsbnd H stretch in the formation of TiO2 NPs. The XRD spectrum confirmed that the synthesized TiO2 NPs were in the form of nanocrystals, as evidenced by the peaks at 2θ values of 27.47°, 31.77°, 36.11°, 41.25°, 54.39°, 56.64° and 69.54° were identified as 110, 100, 101, 111, 211, 220 and 301 reflections, respectively. The crystallite sizes were calculated using Scherrer's formula applied to the major intense peaks and found to be the size of 40.50 nm. The morphological characterization was analyzed by FESEM and the analysis showed the NPs smooth shaped, spherical and uneven. GC-MS analysis showed the main compounds found in A. hydrophila were uric acid (2.95%), glycyl-L-glutamic acid (6.90%), glycyl-L-proline (74.41%) and l-Leucyl-d-leucine (15.74%). The potential glycyl-L-proline could have played an important role as a capping agent. A possible mechanism for the biosynthesis of TiO2 NPs has been proposed. The antibacterial activity of the synthesized TiO2 NPs was assessed by well diffusion method toward A. hydrophila, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes and Enterococcus faecalis and showed effective inhibitory activity against S. aureus (33 mm) and S. pyogenes (31 mm).

  16. Occurrence and antibiotic resistance of mesophilic Aeromonas in three riverine freshwaters of Marrakech, Morocco.

    Science.gov (United States)

    Imziln, B

    2001-12-01

    In order to evaluate the impact of pollution and sewage on the occurrence and antibiotic resistance of mesophilic aeromonads in riverine freshwaters of Marrakech, samples were collected from three rivers (Oukaimeden, Ourika, and Tensift) upstream and downstream from the principal bordering villages. During a 2-year study, indicators of pollution increased dramatically in the downstream waters. Bacterial indicators (faecal coliforms and faecal streptococci) correlated with mesophilic aeromonads only in heavily polluted waters. In low and moderately polluted sources, densities of mesophilic aeromonads were independent of water quality indicators and did not correlate statistically with faecal indicators. Average counts of Aeromonas in low and heavily polluted waters were 2.5 x 10(3) and 2.1 x 10(6) colony forming units per 100 ml, respectively. The biochemical identification of 841 isolates indicated a predominance of A. caviae in heavily and moderately polluted water and sediment. A. hydrophila was dominant only in low polluted waters and when the temperature was below 12 degrees C. High densities of A. sobria were found in low, moderately polluted, or cleaned waters and when the water temperature was above 18 degrees C. All selected isolates (total = 841) were tested for antibiotic susceptibility against 21 antibiotics. Antibiotic resistance frequencies recorded were: ampicillin and amoxicillin, 100%; novobiocin, 96%; cefalotin, 81%; colistin, 72%; sulfamethoxazole, 40%; cefamandole, 37%; polymyxin B, 23%; trimethoprim, 17%; erythromycin, 15%; streptomycin, 8%; amoxicillin-clavulanate, 5%. Resistance to cefotaxime, kanamycin, gentamycin, chloramphenicol, tetracycline, oxytetracycline, nalidixic acid, rifampicin, or trimethoprim-sulfameth-oxazole was found to be polluted samples. Since no correlation between mesophilic aeromonads and conventional faecal pollution indicators was observed in low or moderately polluted waters, and since these freshwaters are used for

  17. Antimicrobial activity of some of the south-Indian spices against serotypes of Escherichia coli, Salmonella, Listeria monocytogenes and Aeromonas hydrophila Atividade antimicrobiana de condimentos do sul da India sobre Escherichia coli, Salmonella, Listeria monocytogenes e Aeromonas hydrophila

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    M.N. Indu

    2006-06-01

    Full Text Available Antibacterial activity of extracts of Allium sativum (garlic, Myristica fragrans (nutmeg, Zingiber officinale (ginger, Allium cepa (onion and Piper nigrum (pepper has been evaluated against 20 different serogroups of Escherichia coli, 8 serotypes of Salmonella, Listeria monocytogenes and Aeromonas hydrophila. Garlic extract showed excellent antibacterial activity against all the test organisms, except L. monocytogenes. Nutmeg showed good anti-listerial activity, although activity against E. coli and Salmonella were serotype dependent. Both garlic and nutmeg extracts were effective against A. hydrophila. Extracts of ginger showed inhibitory activity against two serogroups of E. coli: as O8 (enterotoxigenic E. coli and O88 only. Extracts of onion and pepper did not show any antibacterial activity against the test organisms.Avaliou-se a atividade antimicrobiana de extratos de alho (Allium sativum, noz-moscada (Mysritica frangrans, gengibre (Zingiber officinale cebola (Allium cepa e pimenta do reino (Piper nigrum sobre 20 sorotipos de Escherichia coli, 8 sorotipos de Salmonella, Listeria monocytogenes e Aeromonas hydrophila. O alho apresentou atividade antimicrobiana excelente sobre todos os microrganismos testados, excepto L. monocytogenes. A noz-moscada apresentou boa atividade antilisteria, emboara atividade sobre E. coli e Salmonella tenha sido sorotipo-dependente. Tanto alho como noz-moscada foram eficientes contra A. hydrophila. O extrato de gengibre apresentou atividade inibitória sobre dois sorotipos de E. coli: 08 (enterotoxigenico e 088. Os extratos de cebola e pimenta do reino não apresentaram nenhuma atividade contra os microrganismos testados.

  18. Concentração inibitória mínima de oxitetraciclina para isolados de Aeromonas Hydrophila obtidos de diferentes fontes Minimal inhibitory concentration to oxitetracycline in Aeromonas Hydrophila strains isolated from different sources

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    Delton José Pereira Júnior

    2006-12-01

    Full Text Available Objetivou-se com este trabalho determinar a concentração inibitória mínima (MIC de oxitetraciclina para isolados de Aeromonas hydrophila obtidos de pescado, água de cultivo de peixes e casos de septicemia hemorrágica em peixes. Foi determinado MIC de 100 isolados de A. hydrophila, oriundos de 12 pisciculturas localizadas nos Estados de Minas Gerais, Rio de Janeiro e Rio Grande do Sul, utilizando a técnica de macrodiluição em caldo. Os resultados demonstraram que 14 isolados apresentaram MIC>100 µg/mL (resistentes e 86 apresentaram MICThe aim of this paper was to determine the minimal inhibitory concentration (MIC to oxitetracycline in Aeromonas hydrophila strains isolated from marketed fish, pond water of piscicultures and fish suffering hemorrhagic septicemia. These strains were obtained from 12 different piscicultures from Minas Gerais, Rio de Janeiro e Rio Grande do Sul states. It was determined the MIC to 100 strains, using the broth macrodilution method, and the results showed that 86 strains shown value of MIC100µg/mL (classified as resistant. No differences were observed among strains isolated from marketed fish, pond water and disease outbreaks. I was concluded that the variation detected may represent a risk of selection of resistant bacterial strains in aquatic environments under use of oxitetracycline.

  19. Bacillus sp. QSI-1 Modulate Quorum Sensing Signals Reduce Aeromonas hydrophila Level and Alter Gut Microbial Community Structure in Fish

    Science.gov (United States)

    Zhou, Shuxin; Zhang, An; Yin, Hongping; Chu, Weihua

    2016-01-01

    Quorum sensing (QS) is a cell density dependent process that enables bacteria to communicate with each other based on the production, secretion and sensing of the auto-inducer molecules and then subsequently regulate virulence associated gene expression. Interrupting quorum sensing may represent a novel alternative approach to combat bacterial pathogen. Several bacteria can produce quorum quenching (QQ) enzymes. However, the role of QQ bacteria in shaping the microbiota and the level of N-acyl-homoserine lactones (AHLs, a prevalent type of QS molecules) producing bacteria remains largely unknown. The objective of this study was to examine the presence of AHLs in the fish intestine and investigate the modulation of gut microbiota and its effect on Aeromonas hydrophila level by a QQ enzyme producing probiotic Bacillus sp. QSI-1. AHLs were found in fish gut content and were confirmed in Aeromonas species using Chromobacterium violaceum CV026 and Agrobacterium tumefaciens AT 136 (pZLR4) as reporter strains. We demonstrated that the composition of fish gut microbiota was affected by quenching bacteria QSI-1, and the percentage of A. hydrophila was decreased significantly. Taken together, these results provide valuable insights into QQ enzyme producing probiotics can modulate the microbiota structure and decrease the percentage of AHL-producing pathogenic bacteria in the gut. These data strongly suggest that QQ probiotics may serve as non-antibiotic feed additive in aquaculture to control bacterial diseases. PMID:28018866

  20. Determination of the viability of Aeromonas hydrophila in different types of water by flow cytometry, and comparison with classical methods.

    Science.gov (United States)

    Pianetti, Anna; Falcioni, Tania; Bruscolini, Francesca; Sabatini, Luigia; Sisti, Elivio; Papa, Stefano

    2005-12-01

    The presence of Aeromonas spp. in water can represent a risk for human health. Therefore, it is important to know the physiological status of these bacteria and their survival in the environment. We studied the behavior of a strain of Aeromonas hydrophila in river water, spring water, brackish water, mineral water, and chlorinated drinking water, which had different physical and chemical characteristics. The bacterial content was evaluated by spectrophotometric and plate count techniques. Flow cytometric determination of viability was carried out using a dual-staining technique that enabled us to distinguish viable bacteria from damaged and membrane-compromised bacteria. The traditional methods showed that the bacterial content was variable and dependent on the type of water. The results obtained from the plate count analysis correlated with the absorbance data. In contrast, the flow cytometric analysis results did not correlate with the results obtained by traditional methods; in fact, this technique showed that there were viable cells even when the optical density was low or no longer detectable and there was no plate count value. According to our results, flow cytometry is a suitable method for assessing the viability of bacteria in water samples. Furthermore, it permits fast detection of bacteria that are in a viable but nonculturable state, which are not detectable by conventional methods.

  1. Resistance of genetically different common carp, Cyprinus carpio L., families against experimental bacterial challenge with Aeromonas hydrophila.

    Science.gov (United States)

    Jeney, G; Ardó, L; Rónyai, A; Bercsényi, M; Jeney, Z

    2011-01-01

    The objective of this study was to determine the differences in disease resistance against artificial infection with Aeromonas hydrophila between genetically different common carp families. Four strains differing in their origin and breeding history were selected from the live gene bank of common carp maintained at the Research Institute for Fisheries, Aquaculture and Irrigation (HAKI, Szarvas, Hungary) to establish families with wide genetic background: Szarvas 15 (15), an inbred mirror line; Tata (T) scaly noble carp; Duna (D), a Hungarian wild carp and Amur (A), an East Asian wild carp. A diallele mating structure was used to allow the assessment of genetic variation within and between the tested 96 families for a variety of traits. The existing technologies of fertilization and incubation of carp eggs, as well as larval and fingerling rearing had been modified because of the large number of baseline populations. Two challenge trials of the 96 families of carp with Aeromonas hydrophila were done. The 10 most resistant and 10 most susceptible families to A. hydrophila were identified from these two challenges. The crosses that produced the most resistant families were mainly those having parents from Tata and Szarvas 15 domesticated strains, while the most susceptible families were from the wild strains Duna and Amur.

  2. First isolation of Aeromonas salmonicida subspecies salmonicida from diseased sea bass, Dicentrarchus labrax (L., cultured in Spain

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    Clara Fernández-Álvarez

    2016-11-01

    Full Text Available This work represents the first description of Aeromonas salmonicida subsp. salmonicida as causative agent of furunculosis in cultured sea bass, Dicentrarchus labrax (L.. Cumulative mortality in affected fish from two floating cages in the Mediterranean coast of Spain was 3.8%. Affected sea bass did not show the typical external signs of furunculosis in the first stages of the disease, however, when the disease progressed, open ulcers appeared on the skin and muscle. Internally, splenomegaly was the only pathological sign observed. Samples from diseased fish were subjected to standardized assays for pathogens screening. Negative results were obtained for parasites and fish viruses. A Gram-stain-negative rod-shaped bacterium was observed in smears from liver, kidney and spleen of all analysed fish. Pure bacterial cultures were recovered from liver, kidney and spleen of all diseased fish sampled during the two different outbreaks. Bacteriological, serological, molecular and chemotaxonomic analysis allowed the identification of the causative agent of sea bass mortalities as Aeromonas salmonicida subsp. salmonicida. The bacterial strains were susceptible to most of antimicrobial agents usually employed in aquaculture except to oxytetracycline. Pathogenicity assays demonstrated that the isolated bacteria were virulent for sea bass, turbot and rainbow trout.

  3. White Mulberry (Morus alba Foliage Methanolic Extract Can Alleviate Aeromonas hydrophila Infection in African Catfish (Clarias gariepinus

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    Atefeh Sheikhlar

    2014-01-01

    Full Text Available Two experiments were simultaneously conducted with Morus alba (white mulberry foliage extract (MFE as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp. in African catfish (Clarias gariepinus. In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC, albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM. Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish.

  4. White mulberry (Morus alba) foliage methanolic extract can alleviate Aeromonas hydrophila infection in African catfish (Clarias gariepinus).

    Science.gov (United States)

    Sheikhlar, Atefeh; Alimon, Abd Razk; Daud, Hassan; Saad, Chee R; Webster, Carl D; Meng, Goh Yong; Ebrahimi, Mahdi

    2014-01-01

    Two experiments were simultaneously conducted with Morus alba (white mulberry) foliage extract (MFE) as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp.) in African catfish (Clarias gariepinus). In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM) of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC), albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM). Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish.

  5. PEMBERIAN PROBIOTIK LACTOBACILLUS BREVIS DAN PREBIOTIK OLIGOSAKARIDA PADA BENIH PATIN SIAM (Pangasionodon hypophthalmus YANG DIINFEKSI Aeromonas hydrophila

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    Yuke Eliyani

    2013-08-01

    Lactobacillus brevis, prebiotik oligosakarida dan sinbiotiknya terhadap jumlah bakteri Lactobacillus sp. dan total bakteri dalam usus, total eritrosit, total leukosit, diferensial leukosit, aktivitas fagositik, sintasan, tingkat pertumbuhan, serta FCR benih ikan patin siam yang diinfeksi Aeromonas hydrophila. Hasil uji karakteristik menunjukkan bahwa jenis probiotik dan patogen adalah Lactobacillus sp. dan Aeromonas hydrophila. Pada uji in vivo digunakan lima perlakuan yang terdiri atas K(+, K(-, probiotik (pro, prebiotik (pre serta sinbiotik (sin. Bakteri Lactobacillus sp. ditemukan di usus pada perlakuan probiotik dan sinbiotik dengan kisaran jumlah sekitar 101 sampai 106 (CFU/g. Total eritrosit, total leukosit, aktivitas fagositik berbeda nyata (P<0,05 dengan kontrol pada beberapa waktu pengamatan. Tingkat sintasan terendah diperoleh pada perlakuan K(+ sebesar 43,33±11,55; sedangkan empat perlakuan lainnya memperoleh nilai 100%. Tingkat pertumbuhan harian berbeda nyata antar perlakuan, nilai terbaik dicapai pada perlakuan pemberian sinbiotik sebesar 3,370±0,14. Nilai FCR perlakuan probiotik, prebiotik dan sinbiotik menunjukkan beda nyata dengan kontrol. Perlakuan sin, pre, pro memberikan nilai yang lebih baik pada total eritrosit, total leukosit, aktivitas fagositik, sintasan, pertumbuhan, dan FCR dibandingkan kontrol.

  6. In vitro antimicrobial activity of ethanolic extracts obtained from Ficus spp. leaves against the fish pathogen Aeromonas hydrophila

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    Tkachenko Halyna

    2016-12-01

    Full Text Available The main goal of this study was to determine in vitro antimicrobial activity of ethanolic extracts obtained from the leaves of various Ficus species against Aeromonas hydrophila isolated locally from infected rainbow trout (Oncorhynchus mykiss Walbaum with the aim of providing scientific rationale for the use of the plant in the treatment of bacterial infections induced by Aeromonas spp. in fish. Antimicrobial susceptibility testing was done on Muller-Hinton agar with the disc diffusion method. In the present study, most ethanolic extracts proved effective against the A. hydrophila tested, with 10-12 mm inhibition zones observed. A. hydrophila demonstrated the highest susceptibility to F. pumila. Among various species of Ficus with moderate activity against A. hydrophila, the highest antibacterial activities were noted for F. benghalensis, F. benjamina, F. deltoidea, F. hispida, and F. lyrata. Thus, Ficus can be used as a natural antiseptic and antimicrobial agent in veterinary practice. Further investigations need to be conducted to isolate and identify the bioactive compounds that can then be subjected to detailed pharmacological studies and the development of clinical applications. The alarming rate of increasing resistance in bacterial pathogens in aquaculture environments means that medicinal plants with antibacterial properties are very important as natural resources of new active compounds.

  7. Production of N-acetyl-beta-D-glucosamine from chitin by Aeromonas sp. GJ-18 crude enzyme.

    Science.gov (United States)

    Kuk, J H; Jung, W J; Jo, G H; Kim, Y C; Kim, K Y; Park, R D

    2005-08-01

    A bacterium, GJ-18, having strong chitinolytic activity was isolated from coastal soil. The isolated strain was identified as Aeromonas sp. by morphological and biochemical properties along with 16S rRNA gene sequence. The crude chitinolytic activity of culture supernatants was maximal on the 5th day of culture. Below 45 degrees C, chitin was effectively hydrolyzed to N-acetyl-beta-D-glucosamine (GlcNAc) by Aeromonas sp. GJ-18 crude enzymes, but hydrolysis decreased markedly above 50 degrees C. The optimum pH for enzyme activity was 5.0. TLC and HPLC analysis revealed that, below 45 degrees C, the major reaction product was GlcNAc with a small amount of (GlcNAc)(2) and (GlcNAc)(3), whereas above 50 degrees C the major product was (GlcNAc)(2). When swollen chitin (100 mg) was incubated with crude enzyme preparations (10 U) at 40 degrees C, chitin was hydrolyzed to 83.0 and 94.9% yield of GlcNAc within 5 and 9 days, respectively.

  8. UJI AKTIVITAS ANTIBAKTERI EKSTRAK RUMPUT LAUT Kappaphycus alvarezii DAN Eucheuma denticullatum TERHADAP BAKTERI Aeromonas hydrophila DAN Vibrio harveyii

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    Dwi Budi Wiyanto

    2010-04-01

    Full Text Available Penelitian tentang Uji Aktivitas Antibakteri Ekstrak Rumput Laut Kappaphycus alvarezii dan Eucheuma denticullatum Terhadap Bakteri Aeromonas hydrophila dan Vibrio harveyii dilakukan, mengingat banyak dijumpai  penyakit pada usaha budidaya ikan dan udang, terutama bakteri Aeromonas hydrophila dan Vibrio harveyii. Penelitian ini bertujuan untuk mengetahui efektifitas senyawa bioaktif rumput laut K. alvarezii dan E. denticullatum yang diekstrak menggunakan pelarut metanol dan etanol sebagai antibakteri terhadap A. hydrophila dan V. harveyii.  Penelitian dilakukan sebanyak dua tahap, yaitu: (1 Uji aktivitas antibakteri ekstrak rumput laut; dan (2 Analisa senyawa bioaktif yang terdapat pada ekstrak rumput laut, dimana masing-masing tahapan dianalisis menggunakan rancangan acak lengkap faktorial. Hasil penelitian menunjukkan, dua jenis ekstrak rumput laut dengan pelarut metanol dan etanol, mempunyai daya antibakteri terhadap A. hydrophila dan V. harveyii. Ekstrak E. denticullatum dengan pelarut metanol memiliki daya hambat lebih luas dibanding ekstrak K. alvarezii dengan pelarut metanol terhadap A. hydrophila (19.43±0,55 mm. Ekstrak E. denticullatum dengan pelarut metanol memiliki daya hambat lebih luas dibanding ekastrak K. alvarezii dengan pelarut metanol terhadap V. harveyii (19.85±0,23 mm. Asam heksadekanoat merupakan senyawa paling dominan dijumpai pada ekstrak rumput laut K. alvarezii, dan E. denticullatum yang diekstrak menggunakan pelarut metanol. Kata Kunci : Aktivitas Antibakteri, Rumput laut K. alvarezii dan E. denticullatum,  Bakteri A.  hydrophila dan V. harveyii. 

  9. VAKSINASI IKAN TILAPIA (Oreochromis niloticus MENGGUNAKAN VAKSIN MONOVALEN DAN BIVALEN UNTUK PENCEGAHAN PENYAKIT MOTILE AEROMONAS SEPTICEMIA DAN STREPTOCOCCOSIS

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    Desy Sugiani

    2013-08-01

    Full Text Available Peningkatan respon antibodi pascavaksinasi dengan antigen tunggal dan campuran dari bakterin Aeromonas hydrophila and Streptococcus agalactiae diharapkan dapat meningkatkan daya tahan ikan tilapia (Oreochromis niloticus terhadap penyakit Motile Aeromonas Septicemia/MAS dan Streptococcosis. Sediaan vaksin disiapkan dengan metode pembuatan dan formula yang berbeda, proses inaktifasi dilakukan dengan menambahkan 3% Neutral Buffer Formalin (NBF 10% pada biakan bakteri dalam media tumbuh BHI dan TSB. Vaksinasi diberikan melalui injeksi intraperitoneal dengan sediaan vaksin monovalen A. hydrophila, monovalen S. agalactiae, dan bivalen A. hydrophila + S. agalactiae (Sel utuh, produk ektraselular/ECP, crude supernatan, campuran sel utuh + ECP, dan broth. Uji tantang dilakukan menggunakan dosis LD50 infeksi tunggal maupun ko-infeksi dari bakteri A. hydrophila dan S. agalactiae. Efektivitas dan keampuhan vaksin tersebut dihitung berdasarkan nilai RPS (Relative Percent Survival dan hasil respon hematologi. Titer antibodi dapat terdeteksi setelah satu minggu pemeliharaan pasca vaksinasi. Nilai titer antar perlakuan vaksin bivalen berbeda nyata (P<0.05 dengan vaksin monovalen dan kontrol. Nilai RPS vaksin bivalen (campuran sel utuh + ECP mencapai 100 untuk uji tantang dengan A. hydrophila dan 56,7 pada uji tantang ko-infeksi. Vaksin monovalen A. hydrophila maupun S. agalactiae hanya mampu memproteksi terhadap bakteri homolog, tidak terjadi proteksi silang di antara keduanya.

  10. Complete Genome Sequence of the Highly Virulent Aeromonas schubertii Strain WL1483, Isolated from Diseased Snakehead Fish (Channa argus) in China.

    Science.gov (United States)

    Liu, Lihui; Li, Ningqiu; Zhang, Defeng; Fu, Xiaozhe; Shi, Cunbin; Lin, Qiang; Hao, Guijie

    2016-01-21

    We sequenced the complete genome of the highly virulent Aeromonas schubertii strain WL1483, which was isolated from diseased snakehead fish (Channa argus) in China. The full genome sequence of A. schubertii WL1483 is 4,400,034 bp, which encodes 4,376 proteins and contains 195 predicted RNA genes.

  11. Aeromonas hydrophila as an agent of infection in alligators. Phase I, final report. Progress report, September 1, 1976--September 30, 1977, Part I

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    Gorden, R.W.; Esch, G.W.

    1977-01-01

    Experimental alligators were exposed to various concentrations of young, washed cells of Aeromonas hydrophila under controlled conditions. Responses of all alligators were monitored on the basis of: observations of external lesions; immunoglobulin production; blood chemistry and hematology; bacteriology, parasitology, and pathology of internal organs, skeletal muscle and external lesions at necropsy. The findings are summarized.

  12. A Case of Extrusion of a Solid Silicone Tire Migrating through the Superior Rectus Muscle with Aeromonas hydrophila Infection following a Scleral Buckling Procedure

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    Shinji Makino

    2012-01-01

    Full Text Available To our knowledge, there are no reports of Aeromonas hydrophila infection after a scleral buckling procedure. Also, migration of a silicone explant element through the rectus muscles is extremely rare. Herein, we describe a case experiencing extrusion of a solid silicone tire migrating through the superior rectus muscle with Aeromonas hydrophila infection following a scleral buckling procedure. A 42-year-old man was referred to our hospital complaining of ocular pain and purulent discharge in his left eye which has persisted for several months. He had a history of bilateral rhegmatogenous retinal detachment which had been treated with scleral buckling. The left eye showed extrusion of the solid silicone buckle which had migrated through the superior rectus muscle and an infection in the upper quadrant of the sclera. The buckle was removed, and the patient was treated with antibiotics. After the removal of the buckle, the symptoms showed rapid amelioration and there was no recurrence of retinal detachment. Aeromonas hydrophila was isolated from the discharge and the removed explant. He used well water in daily life. In this case, the Aeromonas hydrophila infection of the extruded buckle might have originated from contaminated well water.

  13. Complete genome sequence of the highly virulent Aeromonas hydrophila AL09-71 isolated from diseased channel catfish in West Alabama

    Science.gov (United States)

    Aeromonas hydrophila AL09-71 was isolated from diseased channel catfish in West Alabama during a 2009 disease outbreak. The full genome of A. hydrophila AL09-71 is 5,023,861 bp. The availability of this genome will allow comparative genomics to identify genes involved in pathogenesis or immunogens f...

  14. Identification, virulence, and mass spectrometry of toxic ECP fractons of West Alabama isolates of Aeromonas hydrophila obtained from a 2010 disease outbreak

    Science.gov (United States)

    In West Alabama, disease outbreaks in 2009 caused by Aeromonas hydrophila have led to an estimated loss of more than $3 million. In 2010, disease outbreak occurred again in West Alabama, causing losses of hundreds of thousands of pounds of market size channel catfish. During the 2010 disease outbrea...

  15. Identification, virulence, and mass spectrometry of toxic ECP fractions of West Alabama isolates of Aeromonas hydrophila obtained from a 2010 disease outbreak

    Science.gov (United States)

    In West Alabama, disease outbreaks in 2009 caused by Aeromonas hydrophila have led to an estimated loss of more than $3 million. In 2010, disease outbreak occurred again in West Alabama, causing losses of hundreds of thousands of pounds of market size channel catfish. During the 2010 disease outbrea...

  16. Draft Genome Sequence of Aeromonas caviae CH129, a Marine-Derived Bacterium Isolated from the Coast of São Paulo State, Brazil

    Science.gov (United States)

    Alfonso Vargas, Nadia Catalina; Zimpel, Cristina Kraemer; Pessoa, Adalberto; Rivera, Irma Nelly Gutierrez

    2016-01-01

    We report here the draft genome sequence of Aeromonas caviae CH129, a marine-derived bacterium isolated from the coast of São Paulo state, Brazil. Genomic analysis revealed genes encoding enzymes involved in binding, transport, and chitin metabolism and different virulence-associated factors. PMID:27908996

  17. Comparative transcriptional analysis reveals distinct expression patterns of channel catfish genes after the first infection and re-infection with Aeromonas hydrophila

    Science.gov (United States)

    To determine whether transcriptional levels of channel catfish (Ictalurus punctatus) genes are differentially regulated between a first infection with Aeromonas hydrophila and a re-infection, suppression subtractive hybridization (SSH) was performed in this study using anterior kidney cDNA after the...

  18. DIFFERENTIATION OF AEROMONAS ISOLATES OBTAINED FROM DRINKING WATER DISTRIBUTION SYSTEM USING MATRIX-ASSISTED LASER DESCRIPTION/IONIZATION-MASS SPECTROMETRY (MALDI-MS)

    Science.gov (United States)

    The genus Aeromonas is one of several medically significant genera that have gained prominence due to their evolving taxonomy and controversial role in human diseases. In this study, matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to analyze the...

  19. Further Characterization of a Type III Secretion System (T3SS) and of a New Effector Protein from a Clinical Isolate of Aeromonas Hydrophila - Part I

    Science.gov (United States)

    A type III secretion system (T3SS)-associated cytotoxin, AexT, with ADP-ribosyltransferase activity and homology to Pseudomonas aeruginosa bifuncational toxins ExoT/S, was recently identified from a fish pathogen Aeromonas salmonicida. In this study, we reported the molecular cha...

  20. Aeromonas salmonicida subsp. salmonicida strains isolated from Chinese freshwater fish contain a novel genomic island and possible regional-specific mobile genetic elements profiles

    DEFF Research Database (Denmark)

    Long, Meng; Nielsen, Tue Kjærgaard; Leisner, Jørgen Johannes

    2016-01-01

    Two strains of Aeromonas salmonicida, YK and BG, were isolated from largemouth bronze gudgeon and northern whitefish in China, and identified as A. salmonicida subsp. salmonicida based on phylogenetic analysis of vapA and 16S rRNA gene sequences. YK and BG originated from freshwater fish, one of ...

  1. PHENOTYPING, VIRULENCE CHARACTERISTICS OF AEROMONAS SPECIES AND THE EFFECTS OF ESSENTIAL PLANT OILS AS ANTIMICROBIAL AGENTS AGAINST PATHOGENIC ISOLATES FROM DIFFERENT SOURCES

    Directory of Open Access Journals (Sweden)

    Ahmed M.A. Mansour

    2014-01-01

    Full Text Available Aeromonas species are increasingly recognized as enteric pathogens. Faecal samples from 20 cow, 45 sheep; 60 goat and 60 camels were examined for the presence of Aeromonas species, which was also sought in the available drinking water (55 well water and 52 drinking chlorinated tap water were also examined. Aeromonas species was isolated more frequently from goats (21.7% than from other animal groups sampled and isolated more frequently from well water (38.2% than chlorinated supplies (23.0%. A. hydrophilia was the most dominant species isolated from different kinds of samples (13.4%. Whereas A. sobria and A. caviae were isolated in much lower rates 4.7 and 2.1% respectively. There was significant association between the isolation of Aeromonas species from all animal faeces and its presence in drinking water. All isolated strains were examined for the characteristics that are reputed to have roles in pathogenicity. The data reported in this study indicates that the distributions of virulence factors, that regulate the pathogenicity of Aeromonads, are different in clinical and enviromental samples. Aeromonas isolates exhibited multi-drug resistanc amoxicillin, carbenicillin and ampicillin. The most potent antibiotics against Aeromonas species isolated in this study were ceftriaxone, ceftazidime, cefotaxime, cefepime. Essential oils have been tested for in vitro and in vivo antimicrobial activity. Clove, Olive and Peppermint oil exhibited a wide spectrum of antimicrobial activity against all strains used in this study, showed a zone of inhibition ranging from 10.00±0.8 to 14.82±0.41 mm in diameter. Minimum Inhibitory Concentration (MIC for selected oils ranged from 12.8 to 25.6 mg mL-1. Treatment of mice with essential oil for 15 days led to enhance antibody levels in all treated groups and significant clearance of A. hydrophilia from animals. The treated animals had

  2. Selective culturing and genus-specific PCR detection for identification of Aeromonas in tissue samples to assist the medico-legal diagnosis of death by drowning.

    Science.gov (United States)

    Huys, Geert; Coopman, Vera; Van Varenbergh, Dirk; Cordonnier, Jan

    2012-09-10

    The detection of autochthonous aquatic bacteria in tissue samples from drowning cases is increasingly considered as an alternative approach to assist the medico-legal diagnosis of death by drowning. Bacteria belonging to the genus Aeromonas may be suitable candidates for this application as they are ubiquitous in natural aquatic environments but are generally not part of the human microbiota. The research aims of this study were (i) to develop a sensitive, specific and rapid screening and confirmation method for Aeromonas species in tissue samples and (ii) to evaluate aseptic sternal puncture as a post-mortem sample technique and bone marrow as an alternative matrix to provide evidence of death by drowning. The presence of Aeromonas in tissue samples was verified by cultivation using the selective media Ampicillin Dextrin Agar (ADA) and Ryan's Aeromonas Medium. The use of ADA medium was found most optimal for the sensitive, inexpensive and quick detection of aeromonads in human tissue samples. Positive culture plates were confirmed by harvesting all colonies for DNA extraction and subsequent PCR amplification using Aeromonas genus-specific primers. Aeromonads were detected in lung swab, blood and bone marrow of drowned bodies (n=3), but were negative in these three matrices for all negative controls (n=90) tested. Bone marrow proved to be a suitable alternative matrix and can be sampled post-mortem by an aseptic sternal puncture. In conclusion, this study confirms previous indications that aeromonads in cultures from blood of water bodies can be considered a potential marker for drowning. Given the fact that the number of immersed bodies (drowned and non-drowned) included in this study is statistically not significant, however, more tissue samples need to be investigated to confirm the validity of these methods to aid the diagnosis of death by wet drowning.

  3. Diversity and homogeneity among small plasmids of Aeromonas salmonicida subsp. salmonicida linked with geographical origin

    Directory of Open Access Journals (Sweden)

    Sabrina A Attéré

    2015-11-01

    Full Text Available Furunculosis, which is caused by Aeromonas salmonicida subsp. salmonicida, is a major salmonid disease in fish farms worldwide. Several plasmids found in this bacterium confer phenotypes such drug resistance and virulence. Small plasmids (pAsa1, pAsa2, pAsa3, and pAsal1 related to ColE1- and ColE2-type replicons are usually present in its normal plasmidome. In the present study, with the objective to investigate if these plasmids display particularities related to the origin of the isolates bearing them, a total of 153 isolates, including 78 new and 75 previously described, were analyzed for the presence of small plasmids by PCR and DNA restriction fragment profiling. A geographical dichotomy between Canadian and European isolates for their propensity to do not have pAsa3 or pAsal1 was found. In addition, the genotyping analysis led to the identification of two European isolates harboring an unusual pAsal1. An investigation by next-generation sequencing (NGS of these two isolates shed light on two pAsal1 variants (pAsal1C and pAsal1D. As with pAsal1B, another pAsal1 variant previously described, these two new variants bore a second insertion sequence (ISAS5 in addition to the usual ISAS11. The characterization of these variants suggested that they could predominate over the wild-type pAsal1 in stressful conditions such as growth at temperatures of 25°C and above. To obtain a comprehensive portrait of the mutational pressure on small plasmids, 26 isolates whose DNA had been sequenced by NGS were investigated. pAsa3 and pAsal1 were more prone to mutations than pAsa1 and pAsa2, especially in the mobA gene, which encodes a relaxase and a primase. Lastly, the average copy number of each plasmid per cell was assessed using raw sequencing data. A clear trend with respect to the relative proportion per cell of each plasmid was identified. Our large-scale study revealed a geographical dichotomy in small plasmid repertoire in addition to a clear trend

  4. Exposure to pairs of Aeromonas strains enhances virulence in the Caenorhabditis elegans infection model

    Science.gov (United States)

    Mosser, Thomas; Talagrand-Reboul, Emilie; Colston, Sophie M.; Graf, Joerg; Figueras, Maria J.; Jumas-Bilak, Estelle; Lamy, Brigitte

    2015-01-01

    Aeromonad virulence remains poorly understood, and is difficult to predict from strain characteristics. In addition, infections are often polymicrobial (i.e., are mixed infections), and 5–10% of such infections include two distinct aeromonads, which has an unknown impact on virulence. In this work, we studied the virulence of aeromonads recovered from human mixed infections. We tested them individually and in association with other strains with the aim of improving our understanding of aeromonosis. Twelve strains that were recovered in pairs from six mixed infections were tested in a virulence model of the worm Caenorhabditis elegans. Nine isolates were weak worm killers (median time to death, TD50, ≥7 days) when administered alone. Two pairs showed enhanced virulence, as indicated by a significantly shortened TD50 after co-infection vs. infection with a single strain. Enhanced virulence was also observed for five of the 14 additional experimental pairs, and each of these pairs included one strain from a natural synergistic pair. These experiments indicated that synergistic effects were frequent and were limited to pairs that were composed of strains belonging to different species. The genome content of virulence-associated genes failed to explain virulence synergy, although some virulence-associated genes that were present in some strains were absent from their companion strain (e.g., T3SS). The synergy observed in virulence when two Aeromonas isolates were co-infected stresses the idea that consideration should be given to the fact that infection does not depend only on single strain virulence but is instead the result of a more complex interaction between the microbes involved, the host and the environment. These results are of interest for other diseases in which mixed infections are likely and in particular for water-borne diseases (e.g., legionellosis, vibriosis), in which pathogens may display enhanced virulence in the presence of the right partner. This

  5. Molecular Identification of 4 Strains of Aeromonas Based on 16 S rDNA Sequence%基于16SrDNA序列的4株气单胞菌属细菌的分子鉴定

    Institute of Scientific and Technical Information of China (English)

    谭凤霞

    2012-01-01

    16SrDNA sequences were amplified and sequenced for four Aeromonas bacteria strains isolated from the aquacul-ture water. The homologous sequences were searched and retrieved using BLAST, then sequences were aligned by MegAlign sofeware using Jotun Hein, ClustalV and ClustalW methods. Phylogenetic trees were constructed by Mega 4.0 software using Neighbor-joining (N-J), minimum evolution (ME), maximum parsimony (MP) and UPGMA methods. Sequences analysis showed that there are 99.2% (Jotun Hein) similarity between Aeromonas sp. T3 16 S rDNA and DQ817542.1, DQ817645.1 and HM127065.1; Aeromonas sp. T4 and DQ816364.1, HM77846.1 and HM778618.1 have 97.9% (Jotun Hein) similarity; Aeromonas sp. T5 and GQ205446.1 have 99.4% (Jotun Hein) similarity; Aeromonas sp. T6 and GQ205446.1 have 99.6% (Jotun Hein) similarity. Similar results were supported by the other two alignment methods. Phylogenetic trees constructed by the four methods showed similar results, and the taxonomic status for the four isolated strains could be investigated. Results showed that Aeromonas sp. T3 and DQ817542.1, Aeromonas sp. T4 and HM778618.1, Aeromonas sp. T5 and CQ232759.1, Aeromonas sp. T6 and GQ205446.1 had the closest relationship, respectively.%对分离自养殖水环境的4株气单胞菌属(A eromonas)细菌的16 S rDNA序列进行PCR扩增并测定其核酸序列,通过BLAST软件在GenBank中查找同源序列,应用MegAlign软件中的Jotun Hein、ClustalV以及ClustalW 3种方法进行序列差异和同源性分析,分别使用Mega 4.0软件中的邻接法(NJ)、最小进化法(ME)、最大简约法(MP)、非加权组平均法(UPGMA)构建系统发育树.由Jotun Hein法可知,Aeromonas sp.T3与序列DQ817542.1、DQ817645.1以及HM127065.1相似度最高,均为99.2%,Aeromonas sp.T4与序列DQ816364.1、HM77846.1以及HM778618.1相似度最高,均为97.9%,A eromonas sp.T5与序列GQ205446.1相似度最高,均为99.4%,Aeromonas sp.T6与序列GQ205446.1相似度最高,为99.6%;其

  6. Pemanfaatan ekstrak daun inai (Lawsonia inermis l. sebagai bakterisida terhadap Aeromonas hydrophila yang menginfeksi ikan lele sangkuriang (Clarias gariepinus

    Directory of Open Access Journals (Sweden)

    Sofyatuddin Karina

    2015-12-01

    Full Text Available Abstract. The objective of this research was to find out the effectiveness of henna leaf extract (Lawsonia inermis L. on A. hydrophila in vitro and its effect on the survival rate of Clarias gariepinus that infected by those bacterias in vivo. The research was conducted at chemistry laboratory of Teacher Training and Education Faculty, Syiah Kuala University and at Microbiology laboratory, Brackishwater aquaculture Department Center, Ujong Batee on Avril to September, 2015. The research involved in vitro test with the inhibition zone as measured parameter and in vivo test with the survival rate value as measured parameter. The treated concentrations were 1, 2, 3, 4 and 5% of extract. The result of in vitro test showed that henna leaf extract was effective against A. hydrophila with the inhibition zone for 1, 2, 3, 4, and 5% extract were 5.45; 5.7; 6.5; 7.5; and 9.6 mm, respectively. The result of ANOVA test showed that henna leaf extract has a significant effect on the survival rate of catfish (P<0.05. The best survival rate was obtained at 4% of extract  concentration.   Keywords: Aeromonas hydrophila; henna leaf extract; catfish Abstrak. Penelitian ini bertujuan untuk mengetahui efektivitas ekstrak daun inai (Lawsonia inermis L. terhadap A. hydrophila secara in vitro dan pengaruhnya secara in vivo terhadap kelangsungan hidup ikan lele sangkuriang (Clarias gariepinus yang terinfeksi bakteri ini dengan cara perendaman. Penelitian ini dilakukan di Laboratorium kimia, FKIP Unsyiah dan Laboratorium Mikrobiologi Balai Budidaya Perikanan Air Payau (BBAP Ujong Batee pada dari bulan April hingga bulan September 2015. Penelitian ini meliputi uji in vitro dengan parameter uji berupa zona hambat ekstrak terhadap bakteri dan uji in vivo dengan parameter uji berupa nilai kelangsungan hidup ikan lele sangkuriang pasca perlakuan dengan ekstrak. Konsentrasi perlakuan yang dilakukan adalah 1, 2, 3, 4, dan 5%. Hasil uji in vitro menunjukkan bahwa ekstrak daun

  7. Detection of pathogenic Aeromonas hydrophila by quadruple PCR%四重PCR检测致病性嗜水气单胞菌

    Institute of Scientific and Technical Information of China (English)

    韦信贤; 杨先乐; 童桂香; 吴祥庆; 谢宗升; 黄国秋; 廖永志; 叶欣宇; 黎小正

    2013-01-01

    Aeromonas hydrophila can infect an array of animals , including fish , amphibians , reptiles , birds and mammals , and lead to hemorrhagic septicaemia . To develop a rapid and specific quadruple PCR method for the detection of pathogenic Aeromonas hydrophila, four pairs of primers were designed based on the conservative sequences of 16S rRNA gene, ser-ine-protease (ahpA ) gene, aerolysin(aerA ) gene and hemolysin(hlyA ) gene of Aeromonas hydrophila. After optimalizing the reaction conditions , specificity , sensitivity and detection rate of the quadruple PCR method were studied . Results indicated that this method has a high specificity in detecting pathogenic strains of Aeromonas hydrophila but not other irrelative bacteria , and can detect as less as 100 fg DNA of Aeromonas hydrophila. Nine Aeromonas hydrophila strains and fifty-six clinical samples were tested by this quadruple PCR and conventional microbiology methods , and both of the methods could identify these nine Aeromonas hydrophila strains ; the detection rate of the fifty-six clinical samples by quadruple PCR was 21 .4% , which was higher than that by conventional microbiology methods (16 .1% ), and their coherence was 94 .6% . It could be concluded that the quadruple PCR method which can simultaneously detect 16S rRNA gene and three virulent genes of pathogenic Aeromonas hydrophila was well established , and this method is a reliable and convenient method to detect Aeromonas hydrophila and i-dentify specific type of pathogenic or nonpathogenic strains .%目的 建立一种能够快速准确地检测致病性嗜水气单胞菌的四重PCR方法.方法 根据致病性嗜水气单胞菌的丝氨酸蛋白酶(ahpA)基因、气溶素(aerA)基因和溶血素(hlyA)基因的保守序列以及嗜水气单胞菌的16S rRNA基因种属特异性序列分别设计4对特异性引物,通过优化各引物浓度、退火温度和Mg2+浓度,确定了四重PCR的最佳反应条件;然后进行特异性和敏感性试

  8. Aeromonas veronii, a tributyltin (TBT)-degrading bacterium isolated from an estuarine environment, Ria de Aveiro in Portugal.

    Science.gov (United States)

    Cruz, Andreia; Caetano, Tânia; Suzuki, Satoru; Mendo, Sónia

    2007-12-01

    Organotin compounds are used in a variety of industrial processes therefore their subsequent discharge into the environment is widespread. Bacteria play an important role in biogeochemical transformations acting as natural decontamination agents. Therefore, screening for tributyltin (TBT)-resistant and -degrading bacteria is relevant for the selection of isolates with decontamination ability of these polluted areas. With this purpose, 50 strains were isolated from sediment and water from Ria de Aveiro and their tolerance to TBT, up to 3mM, was evaluated. Generally, occurrence of highly TBT-resistant bacteria was observed, and Gram negative bacteria exhibited more tolerance to TBT than Gram positive bacteria. A memory response was observed when bacteria were progressively exposed to increasingly higher TBT concentrations. One isolate, Aeromonas veronii Av27, highly resistant to TBT (3mM) uses this compound as carbon source and degrades it to less toxic compounds.

  9. Screening of Antergic Germ against Aeromonas hydrophila%嗜水气单胞菌拮抗菌的筛选

    Institute of Scientific and Technical Information of China (English)

    单晓枫; 张洪波; 郭伟生; 钱爱东

    2007-01-01

    用平板划线法或点种法对212株分离自养殖水体和水产动物胃肠道的细菌进行筛选,得到1株对嗜水气单胞菌(Aeromonas hydrophila)有拮抗作用的细菌MLS-7.经过生理生化的初步鉴定,该菌为粪肠球菌(Enterococcus faecalis).MLS-7上清液抑菌试验和共培养试验表明其对嗜水气单胞菌有较强的抑菌作用.进一步对MLS-7抑菌谱进行测定,确认其对鱼源的病原菌有一定的抑菌作用.

  10. Quorum sensing in Aeromonas salmonicida subsp. achromogenes and the effect of the autoinducer synthase AsaI on bacterial virulence

    DEFF Research Database (Denmark)

    Schwenteit, Johanna; Gram, Lone; Nielsen, Kristian Fog;

    2011-01-01

    The Gram-negative fish pathogenic bacterium Aeromonas salmonicida possesses the LuxIRtype quorum sensing (QS) system, termed AsaIR. In this study the role of QS in A. salmonicida subsp. achromogenes virulence and pigment production was investigated. Five wild-type Asa strains induced the N......-acyl-homoserinelactone (AHL) monitor bacteria. HPLC–HR-MS analysis identified only one type of AHL, N-butanoyl-L-homoserine lactone (C4-HSL). A knock out mutant of AsaI, constructed by allelic exchange, did not produce a detectable QS signal and its virulence in fish was significantly impaired, as LD50 of the Asa...... an important virulence factor, AsaP1, without affecting bacterial growth, makes A. salmonicida subsp. achromogenes an interesting target organism to study the effects of QS in disease development and QSI in disease control....

  11. [Aeromonas spp. and Plesiomonas shigelloides in bivalves, mud, and water from the Gulf of Nicoya, Costa Rica].

    Science.gov (United States)

    Rodríguez, E; Antillón, F

    1989-06-01

    Bivalves, mud, and surface water were collected at three different sites of the Gulf of Nicoya, Costa Rica, in search of Aeromonas spp. and Plesiomonas shigelloides. For their isolation, these bacteria were enriched in alkaline peptone water and streaked on MacConkey agar and on brilliant green bile inositol agar. This was followed by the biochemical tests necessary for their identification. Thirty-five strains of A. hydrophila, 58 of A. caviae, 43 of A. sobria, and 7 of P. shigelloides were isolated. None of these predominated nor was there any indication of a seasonal distribution along the 15 month's duration of the study. Seven strains of A. hydrophila and two of A. sobria showed the biochemical characteristics associated with toxin production (positive Voges-Proskauer and lysine decarboxylase tests). These species are widely distributed in the gulf and there is risk of contracting an infection while bathing or when eating raw bivalves from this area.

  12. Multiple drug resistance of Aeromonas hydrophila isolates from Chicken samples collected from Mhow and Indore city of Madhyapradesh

    Directory of Open Access Journals (Sweden)

    Kaskhedikar

    2009-02-01

    Full Text Available Fourteen antibacterial agents belonging to 9 different groups of antibiotics viz. aminoglycosides, cephalosporins, nitrofurantoin, fluroquinolones, chloramphenicol, sulphonamides, tetracyclines, penicillin and polymixin were used for in vitro sensitivity testing of Aeromonas hydrophila isolated from fifteen samples of chicken collected from retail shops in Mhow city. The sensitivity (100% was attributed to ciprofloxacin, cefuroxime, ceftriaxone, cephotaxime, chloramphenicol, gentamycin, kanamycin, nitrofurantoin, nalidixic acid and ofloxacin followed by oxytetracycline (50%. All the isolates were resistant to ampicillin and colistin antibiotics. That means, none of the isolates were found to be sensitive for penicillin and polymixin group of antibiotics. Multiple drug resistance was also observed in all A. hydrophila isolates. Out of total isolates, 100% were resistant to two antimicrobial drugs and 50% to three drugs. [Vet. World 2009; 2(1.000: 31-32

  13. PENGEMBANGAN METODE ELISA DAN TEKNIK DETEKSI CEPAT DENGAN IMUNOSTIK TERHADAP ANTIBODI ANTI Aeromonas hydrophila PADA IKAN MAS (Cyprinid carpio

    Directory of Open Access Journals (Sweden)

    Tatik Mufidah

    2015-12-01

    Full Text Available Penelitian ini bertujuan untuk mengembangkan metode ELISA untuk deteksi antibodi anti Aeromonas hydrophila dan membuat alat deteksi cepat terhadap antibodi anti A. hydrophila dengan menggunakan imunostik. Sebanyak enam ekor ikan mas digunakan sebagai hewan uji untuk memproduksi serum seronegatif (baseline dan seropositif. Hewan uji tersebut divaksinasi dengan antigen A. hydrophila dan dikoleksi serumnya tiap minggu. Optimasi metode ELISA dilakukan hingga mendapatkan rasio serum seronegatif dan seropositif yang terbaik. Hasil optimasi metode ELISA kemudian digunakan untuk merakit imunostik dan kemudian mengaplikasikannya pada serum ikan mas. Hasil uji optimasi metode ELISA didapatkan hasil bahwa metode ELISA yang dikembangkan dapat mendeteksi antibodi anti A. hydrophila pada semua serum positif dan menyatakan negatif pada serum seronegatif. Hasil yang sama juga ditunjukkan oleh uji imunostik yang telah dirakit.

  14. The use of eugenol against Aeromonas hydrophila and its effect on hematological and immunological parameters in silver catfish (Rhamdia quelen).

    Science.gov (United States)

    Sutili, Fernando Jonas; Kreutz, Luiz Carlos; Noro, Mirela; Gressler, Leticia Trevisan; Heinzmann, Berta Maria; de Vargas, Agueda Castagna; Baldisserotto, Bernardo

    2014-02-15

    The aim of this study was to evaluate the activity of eugenol against the fish pathogen Aeromonas hydrophila and eugenol's effect on hematological and natural immune parameters in silver catfish (Rhamdia quelen). In vitro, eugenol showed weak activity against A. hydrophila, but in vivo, at a subinhibitory concentration (10 mg L(-1)), it promoted survival in infected silver catfish. Eugenol (50 μg mL(-1)) reduced the hemolytic activity of A. hydrophila supernatant in vitro in fish erythrocytes. Subjecting catfish to eugenol baths (5 and 10 mg L(-1)) for five days did not alter the hematological and immunological parameters studied in this work. Based on these results, eugenol can be used to treat or prevent bacterial diseases in fish.

  15. Recombinant goose-type lysozyme in channel catfish: lysozyme activity and efficacy as plasmid DNA immunostimulant against Aeromonas hydrophila infection.

    Science.gov (United States)

    Pridgeon, Julia W; Klesius, Phillip H; Dominowski, Paul J; Yancey, Robert J; Kievit, Michele S

    2013-10-01

    The objectives of this study were: 1) to investigate whether recombinant channel catfish lysozyme-g (CC-Lys-g) produced in Escherichia coli expression system possesses any lysozyme activity; and 2) to evaluate whether channel catfish lysozyme-g plasmid DNA could be used as an immunostimulant to protect channel catfish against Aeromonas hydrophila infection. Recombinant CC-Lys-g produced in E. coli expression system exhibited significant (P recombinant channel catfish lysozyme-g (pcDNA-Lys-g) was transfected in channel catfish gill cells G1B, the over-expression of pcDNA-Lys-g offered significant (P DNA injection. Macrophages of fish injected with pcDNA-Lys-g produced significantly (P DNA injection. Taken together, our results suggest that pcDNA-Lys-g could be used as a novel immunostimulant to offer immediate protection to channel catfish against A. hydrophila infection.

  16. Role of Aeromonas hydrophila Flagella Glycosylation in Adhesion to Hep-2 Cells, Biofilm Formation and Immune Stimulation

    Directory of Open Access Journals (Sweden)

    Susana Merino

    2014-11-01

    Full Text Available Polar flagellin proteins from Aeromonas hydrophila strain AH-3 (serotype O34 were found to be O-glycosylated with a heterogeneous heptasaccharide glycan. Two mutants with altered (light and strong polar flagella glycosylation still able to produce flagella were previously obtained, as well as mutants lacking the O34-antigen lipopolysaccharide (LPS but with unaltered polar flagella glycosylation. We compared these mutants, altogether with the wild type strain, in different studies to conclude that polar flagella glycosylation is extremely important for A. hydrophila adhesion to Hep-2 cells and biofilm formation. Furthermore, the polar flagella glycosylation is an important factor for the immune stimulation of IL-8 production via toll receptor 5 (TLR5.

  17. Aloysia triphylla essential oil as additive in silver catfish diet: Blood response and resistance against Aeromonas hydrophila infection.

    Science.gov (United States)

    Dos Santos, Alessandro C; Sutili, Fernando J; Heinzmann, Berta M; Cunha, Mauro A; Brusque, Isabel C M; Baldisserotto, Bernardo; Zeppenfeld, Carla C

    2017-03-01

    The essential oil of Aloysia triphylla (EOAT) is a promising product with potential use in aquaculture systems. This study evaluated hematological/biochemical responses and survival of silver catfish (Rhamdia quelen) fed a diet containing EOAT and infected by Aeromonas hydrophila. After 21 days of feeding trial, fish were infected with A. hydrophila following a 10-day period of observation. Blood collection was performed before and after the bacterial challenge. Dietary EOAT by itself seems to affect some blood parameters, decreasing total leukocyte, lymphocyte, and neutrophil counts and increasing total protein values. However, 2.0 mL EOAT/kg diet showed a possible potential protective effect after A. hydrophila infection, maintaining the evaluated parameters similar to basal values (from healthy fish before the feeding trial) and promoting survival of silver catfish.

  18. Identification of Iron and Heme Utilization Genes in Aeromonas and their Role in the Colonization of the Leech Digestive Tract

    Directory of Open Access Journals (Sweden)

    Michele eMaltz

    2015-07-01

    Full Text Available It is known that many pathogens produce high-affinity iron uptake systems like siderophores and/or genes for utilizing iron bound to heme-containing molecules, which facilitate iron-acquisition inside a host. In mutualistic digestive-tract associations, iron uptake systems have not been as well studied. We investigated the importance of two iron utilization systems within the beneficial digestive-tract association Aeromonas veronii and the medicinal leech, Hirudo verbana. Siderophores were detected in A. veronii using chrome azurol S. Using a mTn5, a transposon insertion in viuB generated a mutant unable to acquire iron using siderophores. The A. veronii genome was then searched for genes potentially involved in iron utilization bound to heme-containing molecules. A putative outer membrane heme receptor (hgpB was identified with a transcriptional activator, termed hgpR, downstream. The hgpB gene was interrupted in both the parent strain and the viuB mutant with an antibiotic resistance cassette, yielding a hgpB mutant and a mutant with both iron uptake systems inactivated. In vitro assays indicated that hgpB is involved in utilizing iron bound to heme and that both iron utilization systems are important for A. veronii to grow in blood. In vivo colonization assays revealed that the ability to acquire iron from heme-containing molecules is critical for A.veronii to colonize the leech gut. Since iron and specifically heme utilization is important in this mutualistic relationship and has a role as a possible virulence factor in other organisms, genomes from different Aeromonas strains (both clinical and environmental were queried with iron utilization genes of A. veronii. This analysis revealed the heme utilization genes are widely distributed among aeromonads. In addition, aeromonads posses a suite of genes involved in iron acquisition. These data further confirm symbiotic and pathogenic relationships possess similar mechanisms for interacting with

  19. Identification of iron and heme utilization genes in Aeromonas and their role in the colonization of the leech digestive tract.

    Science.gov (United States)

    Maltz, Michele; LeVarge, Barbara L; Graf, Joerg

    2015-01-01

    It is known that many pathogens produce high-affinity iron uptake systems like siderophores and/or proteins for utilizing iron bound to heme-containing molecules, which facilitate iron-acquisition inside a host. In mutualistic digestive-tract associations, iron uptake systems have not been as well studied. We investigated the importance of two iron utilization systems within the beneficial digestive-tract association Aeromonas veronii and the medicinal leech, Hirudo verbana. Siderophores were detected in A. veronii using chrome azurol S. Using a mini Tn5, a transposon insertion in viuB generated a mutant unable to utilize iron using siderophores. The A. veronii genome was then searched for genes potentially involved in iron utilization bound to heme-containing molecules. A putative outer membrane heme receptor (hgpB) was identified with a transcriptional activator, termed hgpR, downstream. The hgpB gene was interrupted with an antibiotic resistance cassette in both the parent strain and the viuB mutant, yielding an hgpB mutant and a mutant with both iron uptake systems inactivated. In vitro assays indicated that hgpB is involved in utilizing iron bound to heme and that both iron utilization systems are important for A. veronii to grow in blood. In vivo colonization assays revealed that the ability to acquire iron from heme-containing molecules is critical for A. veronii to colonize the leech gut. Since iron and specifically heme utilization is important in this mutualistic relationship and has a potential role in virulence factor of other organisms, genomes from different Aeromonas strains (both clinical and environmental) were queried with iron utilization genes of A. veronii. This analysis revealed that in contrast to the siderophore utilization genes heme utilization genes are widely distributed among aeromonads. The importance of heme utilization in the colonization of the leech further confirms that symbiotic and pathogenic relationships possess similar

  20. Re-identification of Aeromonas isolates from rainbow trout and incidence of class 1 integron and β-lactamase genes.

    Science.gov (United States)

    Vega-Sánchez, Vicente; Latif-Eugenín, Fadua; Soriano-Vargas, Edgardo; Beaz-Hidalgo, Roxana; Figueras, María José; Aguilera-Arreola, Ma Guadalupe; Castro-Escarpulli, Graciela

    2014-08-27

    Forty-eight Aeromonas isolates from rainbow trout previously identified by the 16S rDNA-RFLP technique were re-identified using 2 housekeeping genes (gyrB and rpoD). After sequencing the prevalences of the species were A. veronii (29.2%), A. bestiarum (20.8%), A. hydrophila (16.7%), A. sobria (10.4%), A. media (8.3%), A. popoffii (6.2%), A. allosaccharophila (2.1%), A. caviae (2.1%), A. salmonicida (2.1%) and one isolate (2.1%) belongs to a candidate new species "Aeromonas lusitana". Coincident identification results to the 16S rDNA-RFLP technique were only obtained for 68.8% of the isolates. PCR amplification of the enterobacterial repetitive intergenic consensus (ERIC-PCR) indicated that the 48 isolates belonged to 33 different ERIC genotypes. Several genotypes were isolated from different farms and organs in the same fish, indicating a systemic dissemination of the bacteria. The presence of genes (blaIMP, blaCphA/IMIS, blaTEM, blaSHV and intI1) that encode extended-spectrum beta-lactamases (ESBLs), metallo-beta-lactamases (MBLs) and class 1 integrons were studied by PCR. Only 39.6% (19/48) of the strains showed the presence of one or more resistance genes. The gene blaCphA/IMIS was detected in 29.2% of the isolates, followed by the intI1 (6.2%) and blaSHV (4.2%) genes. The variable region of class 1 integrons of the 3 positive isolates was sequenced revealing the presence of the gene cassette aadA1 (aminoglycoside transferase) that plays a role in streptomycin/spectinomycin resistance.

  1. Determinación de factores de virulencia en cepas de Aeromonas spp., aisladas a partir de pescado

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    William Suárez Q.

    2012-04-01

    Full Text Available Objetivo. Investigar la incidencia de cinco marcadores fenotípicos de virulencia en cepas de Aeromonas aisladas a partir de muestras de pescado expendido en Pamplona, Colombia. Materiales y métodos. Se utilizaron 47 cepas identificadas previamente. Se evaluaron: actividad hemolítica en agar sangre, suplementado con 5% de eritrocitos de cordero y agar sangre suplementado con 5% eritrocitos de sangre humana; actividad proteolítica en agar Mueller-Hinton suplementado al 10% (p/v con leche descremada, actividad lipolítica en agar tributirina; actividad desoxirribonucleasas en agar DNAsa. Resultados. Se encontró que las cepas de A. hydrophila, A. veronii GH 8, A. jandaei, A. veronii GH 10 y A. eucrenophila, demostraron capacidad hemolítica, proteolítica, lipolítica y nucleasa. Todas las cepas de A. popoffii fueron β-hemolíticas en agar sangre humana, proteolíticas y con actividad DNAsa. Las cepas de A. caviae, coincidieron en ser hemolíticas y lipolitícas, mientras que la cepa de A. schubertii, manifestó la presencia de actividad hemolítica y DNAsa. Conclusiones. La frecuencia de los factores de virulencia en las cepas estudiadas fue: el 87% demostraron producción de nucleasas; el 83% fueron β-hemolíticas sobre eritrocitos humanos; el 68% expresaron producción de lipasas, el 63% fueron proteolíticas y el 53% resultaron ser hemolíticas sobre eritrocitos de cordero, indicando estos datos el posible potencial patógeno de las cepas. Estos resultados mostraron que el pescado comercializado en Pamplona, puede ser una fuente importante de especies de Aeromonas que expresan factores asociados a la virulencia para el hombre.

  2. 几种中药单体和抗生素对嗜水气单胞菌及温和气单胞菌的体外抑菌活性研究%IN VITRO ANTIBACTERIAL ACTIVITY OF SEVERAL CHINESE MEDICINE MONOMERS AND ANTIBIOTICS ON AEROMONAS HYDROPHILA AND AEROMONAS SOBRIA

    Institute of Scientific and Technical Information of China (English)

    卢静; 王振宁; 陈锐; 关爽

    2013-01-01

    To investigate the individual and combined in vitro antibacterial activity of 6 Chinese medicine monomers (Gallic acid, Glycyrrhizic acid potassium, Phenanthro, Quercetin, Physcion, Chlorogenic acid) and 3 antibiotics (Nor-floxacin, Norfloxacin, Florfenicol) on Aeromonas hydrophila and Aeromonas sobria, the antibacterial activity of all test substances on the two bacteria was detected by means of the disc diffusion method. The minimal inhibitory concentra-tion bacterial (MIC) and the minimum bacterial concentration (MBC) were determined by the micro double dilution method. The combined antibacterial effect was investigated in the way of chessboard method. Among the 6 Chinese medicine monomers, gallic acid and quercetin showed significant antibacterial effects against Aeromonas hydrophila and Aeromonas sobria, and the inhibitory circle of these two medicines were exceeded 20 mm. MIC and MBC of gallic acid on Aeromonas hydrophila and Aeromonas sobria were both 250 µg/mL. MIC and MBC of quercetin on Aeromonas hydrophila were both 500 µg/mL, and 250 µg/mL and 500 µg/mL on Aeromonas sobria. But the other Chinese medicine monomers showed no effect against these two bacteria. Enrofloxacin, norfoxacin and florfenicol showed significantly antibacterial effect against Aeromonas hydrophila and Aeromonas sobria. The result of combined experiment showed additive inhibition effect on Aeromonas hydrophila by gallic acid with enrofloxacin, gallic acid with florfenicol, and quercetin with florfenicol. The combination of gallic acid and enrofloxacin showed synergetic inhibition effect on Aeromonas sobria. The combination of gallic acid and norfoxacin or florfenicol, quercetin and florfenicol showed addi-tive inhibition effect on Aeromonas sobria. Gallic acid and quercetin showed significant antibacterial activity against Aeromonas hydrophila and Aeromonas sobria. And the combination of them and enrofloxacin, norfoxacin, florfenicol had additive or synergetic inhibition effect

  3. ISOLATION AND IDENTIFICATION OF AEROMONAS HYDROPHILA FROM LAUGHING THRUSHES%噪鹛嗜水气单胞菌的分离与鉴定

    Institute of Scientific and Technical Information of China (English)

    沈素芳

    2001-01-01

    Short motile Gram negative bacteria were isolated from liver and heart of dead laughing thrushes from Shanghai Wildlife Garden. The biochemical and physiologic characteristics of the isolate were similar to those of Aeromonas hydrophila reference strain J-1. Virulence test showed the isolate was highly virulent(LD50=5×103CFU). Morphological, cultural, biochemical and serological tests demonstrated that the isolate is Aeromonas hydrophila.%从上海野生动物园百鸟园饲养的病死噪鹛中分离到一株革兰氏阴性、有运动力的短杆菌。其生化特性为:氧化酶阳性;发酵葡萄糖产酸产气;发酵甘露醇、七叶苷、阿拉伯糖和蔗糖;不发酵肌醇;鸟氨酸脱羧酶阳性,对新生霉素不敏感,VP试验阳性。用致病性嗜水气单胞菌,检测试剂盒试验呈阳性结果。毒力试验显示,分离株对小鼠的LD50为5×103CFU,具有很强的致病性。经鉴定该病原菌为嗜水气单胞菌(Aeromonas hydrophila)。

  4. The involvement of tetA and tetE tetracycline resistance genes in plasmid and chromosomal resistance of Aeromonas in Brazilian strains

    Directory of Open Access Journals (Sweden)

    Ilana Teruszkin Balassiano

    2007-11-01

    Full Text Available This study analyzed the involvement of tetA and tetE genes in the tetracycline resistance of 16 strains of genus Aeromonas, isolated from clinical and food sources. Polymerase chain reactions revealed that 37.5% of the samples were positive for tetA, and also 37.5% were tetE positive. One isolate was positive for both genes. Only the isolate A. caviae 5.2 had its resistance associated to the presence of a plasmid, pSS2. The molecular characterization of pSS2 involved the construction of its restriction map and the determination of its size. The digestion of pSS2 with HindIII originated two fragments (A and B that were cloned separately into the pUC18 vector. The tetA gene was shown to be located on the HindIII-A fragment by PCR. After transforming a tetracycline-sensitive strain with pSS2, the transformants expressed the resistance phenotype and harbored a plasmid whose size was identical to that of pSS2. The results confirmed the association between pSS2 and the tetracycline resistance phenotype, and suggest a feasible dissemination of tetA and tetE among strains of Aeromonas. This study suggests the spreading tetA and tetE genes in Aeromonas in Brazil and describes a resistance plasmid that probably contributes to the dissemination of the resistance.

  5. 缢蛏致病菌气单胞茵的分子生物学鉴定%Identification of Pathogenic Aeromonas from Sinvnovacula constricta by Molecular Biology

    Institute of Scientific and Technical Information of China (English)

    王兴强; 曹梅; 阎斌伦; 张庆起

    2009-01-01

    从患病缢蛏(Sinvnovacula constricta)中分离到一株病原菌,暂命名为12#菌.对该株的16SrDNA的全序列进行PCR扩增并测序,然后用NCBIBLAST对测序结果进行比对.16S rDNA序列分析表明:12#菌与多株气单胞茵的16S rDNA的同源性均在95%vx以上.在细菌系统分类学中应归属于气单胞茵属.从构建的系统发育树中可以看出:12#茵与点状产气单胞茵(Aeromonas punctata)共同构成一个分支,且该菌株与点状产气单胞菌(Aeromonas punctata)的16S rDNA同源性达到99%以上,由此可以初步认为该菌为点状产气单胞茵(Aeromonas punctata).

  6. Development of highly sensitive electrochemical genosensor based on multiwalled carbon nanotubes-chitosan-bismuth and lead sulfide nanoparticles for the detection of pathogenic Aeromonas.

    Science.gov (United States)

    Fernandes, António Maximiano; Abdalhai, Mandour H; Ji, Jian; Xi, Bing-Wen; Xie, Jun; Sun, Jiadi; Noeline, Rasoamandrary; Lee, Byong H; Sun, Xiulan

    2015-01-15

    In this paper, we reported the construction of new high sensitive electrochemical genosensor based on multiwalled carbon nanotubes-chitosan-bismuth complex (MWCNT-Chi-Bi) and lead sulfide nanoparticles for the detection of pathogenic Aeromonas. Lead sulfide nanoparticles capped with 5'-(NH2) oligonucleotides thought amide bond was used as signalizing probe DNA (sz-DNA) and thiol-modified oligonucleotides sequence was used as fixing probe DNA (fDNA). The two probes hybridize with target Aeromonas DNA (tDNA) sequence (fDNA-tDNA-szDNA). The signal of hybridization is detected by differential pulse voltammetry (DPV) after electrodeposition of released lead nanoparticles (PbS) from sz-DNA on the surface of glass carbon electrode decorated with MWCNT-Chi-Bi, which improves the deposition and traducing electrical signal. The optimization of incubation time, hybridization temperature, deposition potential, deposition time and the specificity of the probes were investigated. Our results showed the highest sensibility to detect the target gene when compared with related biosensors and polymerase chain reaction (PCR). The detection limit for this biosensor was 1.0×10(-14) M. We could detect lower than 10(2) CFU mL(-1) of Aeromonas in spiked tap water. This method is rapid and sensitive for the detection of pathogenic bacteria and would become a potential application in biomedical diagnosis, food safety and environmental monitoring.

  7. Isolation and Identification of Aeromonas hydrophila and Saprolegnia sp. on Catfish (Clarias gariepinus) in Floating cages in Bozem Moro Krembangan Surabaya

    Science.gov (United States)

    Kusdarwati, Rahayu; Kismiyati; Sudarno; Kurniawan, Hendi; Teguh Prayogi, Yudha

    2017-02-01

    Catfish (Clarias gariepinus) is one of the familiar freshwater fish cultured in Indonesia farmer. One of the reason is the high mortality of the catfish infected by Aeromonas hydrophila and Saprolegnia sp. Motile Aeromonas septicemia (MAS) is a common bacterial disease, caused by Aeromonas hydrophila, which affects freshwater fish. In Southeast Asia, the outbreak of this disease was firstly reported from West Java in 1980, when a total of 82.5 tons a month of catfish were lost, while in Central Java in 1984, the total loss was 1.6 tons. Saprolegniosis can cause economic loss due to high mortality from its case reaching 10% to 50%. This research aimed to identify and determine the percentage of A. hydrophila and Saprolegnia sp. the catfish farmed in bozem Moro Krembangan, Surabaya, East Java. Meanwhile, a supporting parameter in this research is the value of water quality parameter including pH, temperature, ammonia and dissolved oxygen that were measured during sampling. The results showed that of the 20 samples taken from the two cages, 19 fish were positively infected by A. drophila. percentage of infections of A. hydrophila that infect umbo catfish in Moro Krembangan, was 95%, while the percentage Saprolegnia sp. was 90%.

  8. Attenuated virulence of pigment-producing mutant of Aeromonas veronii bv. sobria in HeLa cells and Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Said K. Abolghait

    2013-06-01

    Full Text Available Aeromonas species are potential water/foodborne pathogens, whereas Aeromonas veronii bv. sobria is one of the most virulent species to human and fish. Most current experimental evidence has publicized that suicide plasmid dependent IS1-element untargeted integration into A. veronii bv. sobria ATCC 9071T strain was recently used to generate brown pigment-producing and spontaneous pelleting (BP+SP+ mutant. Current study was conducted to compare virulence of wild-type ATCC 9071T strain and its BP+SP+ mutant with respect to cytotoxicity in HeLa cells and lethality in Nile tilapia. It was found that the cytotoxicity of wild-type ATCC 9071T strain to HeLa cells has reached 75% versus 50% for the cytotoxicity of BP+SP+ mutant. Further, the median lethal dose (LD50 of wild-type ATCC 9071T strain in Nile tilapia was 8.25 Log10 colony-forming units (CFU/ml, compared to 9.16 Log10 CFU/ml for the LD50 of BP+SP+ mutant. Thus, current study supports the notion that non pigment-producing Aeromonas strains are more virulent than pigment-producing ones.

  9. Diversity of Clavulanic Acid-Inhibited Extended-Spectrum β-Lactamases in Aeromonas spp. from the Seine River, Paris, France▿

    Science.gov (United States)

    Girlich, Delphine; Poirel, Laurent; Nordmann, Patrice

    2011-01-01

    Environmental Aeromonas sp. isolates resistant to ceftazidime were recovered during an environmental survey performed with water samples from the Seine River, in Paris, France, in November 2009. Selected isolates were identified by sequencing of the 16S rRNA and rpoB genes. PCR and cloning experiments were used to identify broad-spectrum-β-lactamase-encoding genes and their genetic context. Clavulanic acid-inhibited extended-spectrum-β-lactamase (ESBL) genes were identified in 71% of the Aeromonas sp. isolates. A variety of ESBL genes were detected, including blaVEB-1a, blaSHV-12, blaPER-1, blaPER-6, blaTLA-2, and blaGES-7, suggesting an aquatic reservoir of those ESBL genes. Moreover, the repeated elements and different insertion sequences were identified in association with the blaPER-6 and the blaVEB-1a genes, respectively, indicating a wide diversity of mobilization events, making Aeromonas spp. a vehicle for ESBL dissemination. PMID:21149627

  10. Aeromonas spp. e Plesiomonas shigelloides isoladas a partir de mexilhões (Perna perna in natura e pré-cozidos no Rio de Janeiro, RJ Aeromonas spp. and Plesiomonas shigelloides isolated from in natura and precooked mussels (Perna perna in Rio de Janeiro, RJ, Brazil

    Directory of Open Access Journals (Sweden)

    Christiane Soares Pereira

    2004-12-01

    Full Text Available O ecossistema aquático é o habitat de mexilhões (Perna perna, animais filtradores que refletem a qualidade ambiental através de análise microbiológica de sua carne. No presente trabalho avaliou-se a presença de patógenos emergentes (Aeromonas hydrophila e Plesiomonas shigelloides, em mexilhões in natura e pré-cozidos coletados por pescadores da Estação Experimental de Cultivo de Mexilhões situada em Jurujuba, Niterói, Rio de Janeiro. Foram analisadas 86 amostras de mexilhões (43 in natura e 43 pré-cozidos as quais foram submetidas a enriquecimento em Água Peptonada Alcalina (APA acrescida de 1 e 3% de Cloreto de Sódio (NaCl e em solução Salina de Butterfield, incubadas a 37ºC por 24 horas. Em seguida, foram semeadas em Ágar Seletivo para Pseudomonas-Aeromonas (GSP, Ágar Tiossulfato Citrato Bile Sacarose (TCBS e Ágar Inositol Bile Verde Brilhante (IBB. A análise geral dos resultados permitiu a identificação de Areomonas spp e Plesiomonas shigelloides em 86% das amostras de mexilhões in natura e pré-cozidas avaliadas. A posterior caracterização bioquímica permitiu a identificação das espécies Aeromonas media (37,10%, A. hydrophila (15,50%, A. caviae (14,80%, A. veronii biogrupo veronii (11,60%, Aeromonas sp. (7,36%, A. sobria (4,20%, A. trota (4,20%, A. schubertii (1,31%, A. jandaei (1,31%, A. veronii biogrupo sobria (0,52% e Plesiomonas shigelloides (2,10%. A relevância epidemiológica desses microrganismos em casos de gastrenterite humana, após consumo de mexilhões crus ou parcialmente cozidos, revela a importância de alertar as autoridades de Saúde Pública no Brasil, sobre a presença desses patógenos na cadeia alimentar e seus riscos para a saúde humana.The aquatic ecosystem is the habitat of mussels, filtrating animals that reflect the ambient quality through microbiological analysis. In the present investigation, we evaluated the presence of emergent pathogens (Aeromonas hydrophila and Plesiomonas

  11. 嗜水气单胞菌及其免疫防控措施的研究进展%Research Progress on the Taxonomic Status, Its Immunity Prevention and Control of Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    秦杨蕾; 毛芝娟; 钱国英

    2015-01-01

    Aeromonas hydrophila is one of common pathogenic microorganism which is widely distributed in nature. In order to prevent the infectious diseases caused by Aeromonas hydrophila, and reduce the damage to human and animals, the taxonomic status of Aeromonas hydrophila, its virulence factors, the immune prevention and control of Aeromonas hydrophila were reviewed in this paper, which will provide the theoretical basis for systemic research of Aeromonas hydrophila.%嗜水气单胞菌作是一种广泛分布于自然界的人畜共有致病微生物,为有效预防嗜水气单胞菌引起的爆发性疾病,以减少对人畜的损害,通过回顾嗜水气单胞菌的分类,对其主要毒力因子和免疫防控的研究成果进行了综述,旨在为后期对嗜水气单胞菌进行系统研究提供理论基础。

  12. Isolation and partial characterization of a virulent bacteriophage IHQ1 specific for Aeromonas punctata from stream water.

    Science.gov (United States)

    Ul Haq, Irshad; Chaudhry, Waqas Nasir; Andleeb, Saadia; Qadri, Ishtiaq

    2012-05-01

    Aeromonas punctata is the causative agent of septicemia, diarrhea, wound infections, meningitis, peritonitis, and infections of the joints, bones and eyes. Bacteriophages are often considered alternative agents for controlling bacterial infection and contamination. In this study, we described the isolation and preliminary characterization of bacteriophage IHQ1 (family Myoviridae) active against the Gram-negative bacterial strain A. punctata. This virulent bacteriophage was isolated from stream water sample. Genome analysis indicated that phage IHQ1 was a double-stranded DNA virus with an approximate genome size of 25-28 kb. The initial characterization of this newly isolated phage showed that it has a narrow host range and infects only A. punctata as it failed to infect seven other clinically isolated pathogenic strains, i.e., methicillin-resistant Staphylococcus aureus 6403, MRSA 17644, Acinetobacter 33408, Acinetobacter 1172, Pseudomonas aeruginosa 22250, P. aeruginosa 11219, and Escherichia coli. Proteomic pattern of phage IHQ1, generated by SDS-PAGE using purified phage particles, showed three major and three minor protein bands with molecular weights ranging from 25 to 70 kDa. The adsorption rate of phage IHQ1 to the host bacterium was also determined, which was significantly enhanced by the addition of 10 mM CaCl(2). From the single-step growth experiment, it was inferred that the latent time period of phage IHQ1 was 24 min and a burst size of 626 phages per cell. Moreover, the pH and thermal stability of phage IHQ1 were also investigated. The maximum stability of the phage was observed at optimal pH 7.0, and it was totally unstable at extreme acidic pH 3; however, it was comparatively stable at alkaline pH 11.0. At 37°C the phage showed maximum number of plaques, and the viability was almost 100%. The existence of Aeromonas bacteriophage is very promising for the eradication of this opportunistic pathogen and also for future applications such as the

  13. Thin-film fixed-bed reactor (TFFBR for solar photocatalytic inactivation of aquaculture pathogen Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Khan Sadia J

    2012-01-01

    Full Text Available Abstract Background Outbreaks of infectious diseases by microbial pathogens can cause substantial losses of stock in aquaculture systems. There are several ways to eliminate these pathogens including the use of antibiotics, biocides and conventional disinfectants, but these leave undesirable chemical residues. Conversely, using sunlight for disinfection has the advantage of leaving no chemical residue and is particularly suited to countries with sunny climates. Titanium dioxide (TiO2 is a photocatalyst that increases the effectiveness of solar disinfection. In recent years, several different types of solar photocatalytic reactors coated with TiO2 have been developed for waste water and drinking water treatment. In this study a thin-film fixed-bed reactor (TFFBR, designed as a sloping flat plate reactor coated with P25 DEGUSSA TiO2, was used. Results The level of inactivation of the aquaculture pathogen Aeromonas hydrophila ATCC 35654 was determined after travelling across the TFFBR under various natural sunlight conditions (300-1200 W m-2, at 3 different flow rates (4.8, 8.4 and 16.8 L h-1. Bacterial numbers were determined by conventional plate counting using selective agar media, cultured (i under conventional aerobic conditions to detect healthy cells and (ii under conditions designed to neutralise reactive oxygen species (agar medium supplemented with the peroxide scavenger sodium pyruvate at 0.05% w/v, incubated under anaerobic conditions, to detect both healthy and sub-lethally injured (oxygen-sensitive cells. The results clearly demonstrate that high sunlight intensities (≥ 600 W m-2 and low flow rates (4.8 L h-1 provided optimum conditions for inactivation of A. hydrophila ATCC 3564, with greater overall inactivation and fewer sub-lethally injured cells than at low sunlight intensities or high flow rates. Low sunlight intensities resulted in reduced overall inactivation and greater sub-lethal injury at all flow rates. Conclusions This

  14. Aeromonas associated diarrhoeal disease in south Brazil: prevalence, virulence factors and antimicrobial resistance Aeromonas associadas a diarréias no sul do Brasil: prevalência, fatores de virulência, e resistência a antibiótico

    Directory of Open Access Journals (Sweden)

    Ivani M.F. Guerra

    2007-12-01

    Full Text Available Aeromonas were isolated from 27 (6.6% of 408 patients admitted with acute gastroenteritis in two hospitals at Rio Grande do Sul, Brazil. Isolates were classified as A. hydrophila (51.8%, A. caviae (40.8%, and A. veronii biotype sobria (7.4%. The highest prevalence of Aeromonas associated infections occurred in lactants and children. Virulence genes (aerA -aerolysin/hemolysin, ahpA -serine-protease, satA - glycerophospholipid-cholesterol acyltransferase, lipA -lipase, and ahyB -elastase and virulence factors (hemolytic, proteolitic, lipolitic activities, and biofilm formation were identified in most A. hydrophila and A. veronii biotype sobria isolates, with lower frequencies on A. caviae. All Aeromonas isolates were resistant to ampicillin, ticarcillin/clavulanic acid, cephalotin, and cephazolin, and most of them (>70% exhibited resistance to imipenem, carbenicillin, amoxillin/sulbactan, and piperacillin. Multiple-resistance, more than four antibiotics, was evidenced in 29.6% of the isolates. The most efficient antibiotics were the quinolones (ciprofloxacin and norfloxacin, and the aminoglycosides (amikacin and netilmicin.Aeromonas foram isoladas de 27 (6.6% dos 408 pacientes admitidos com gastroenterite aguda em dois hospitais do Rio Grande do Sul, Brasil. Os isolados foram classificados com A. hydrophila (51.8%, A. caviae (40.8%, e A. veronii biotype sobria (7.4%. A maior prevalência de Aeromonas ocorreu em lactantes e crianças. Genes (aerA -aerolisina/hemolisina, ahpA -serina-protease, satA - glicerofosfolipidio-colesterol aciltransferase, lipA -lipase, e ahyB -elastase e factores (atividade hemolítica, proteolítica, lipolítica, e formação de biofilme de virulência foram identificados na maioria dos isolados de A. hydrophila e A. veronii biotype sobria, com freqüências menores em A. caviae. Todos os isolados de Aeromonas apresentaram resistência a ampicilina, ticarcilina/ácido clavulânico, cefalotina e cefazolina, e a maior parte

  15. 渗压震扰法释放Aeromonas sp.2016菌株外周间质中几丁质酶的研究%The Release of Chitinase from Periplasm of Aeromonas sp. 2016 by Osmotic Shock

    Institute of Scientific and Technical Information of China (English)

    文红秀; 李昌平

    2005-01-01

    气单胞菌Aeromonas sp.2016菌株能产生多种几丁质酶,其中的胞外酶C可能聚集于细胞外周胞质.为了避免破碎菌体而产生过多的杂蛋白,探索了用渗压震扰法(osmotic shock)来释放这部分酶.主要步骤是:先将菌体悬浮在20%蔗糖-0.03mol/L Tris-HCl(pH8.0)高渗透压的溶液中,再快速转移到纯水低渗透压溶液中,产生瞬间渗压震荡,释放细胞外周胞质中的酶.结果表明,通过渗压震扰法释放出的酶纯度最高,比活力达到142.79U/g,比培养液上清液的54.46U/g和菌体破碎样品的14.66U/g分别高1.6倍和8.7倍,可用于纯化目的蛋白.

  16. Molecular Cloning and Functional Characterization of Mannose Receptor in Zebra Fish (Danio rerio during Infection with Aeromonas sobria

    Directory of Open Access Journals (Sweden)

    Feifei Zheng

    2015-05-01

    Full Text Available Mannose receptor (MR is a member of pattern-recognition receptors (PRRs, which plays a significant role in immunity responses. Much work on MR has been done in mammals and birds while little in fish. In this report, a MR gene (designated as zfMR was cloned from zebra fish (Danio rerio, which is an attractive model for the studies of animal diseases. The full-length cDNA of zfMR contains 6248 bp encoding a putative protein of 1428 amino acids. The predicted amino acid sequences showed that zfMR contained a cysteine-rich domain, a single fibronectin type II (FN II domain, eight C-type lectin-like domains (CTLDs, a transmembrane domain and a short C-terminal cytoplasmic domain, sharing highly conserved structures with MRs from the other species. The MR mRNA could be detected in all examined tissues with highest level in kidney. The temporal expression patterns of MR, IL-1β and TNF-α mRNAs were analyzed in the liver, spleen, kidney and intestine post of infection with Aeromonas sobria. By immunohistochemistry assay, slight enhancement of MR protein was also observed in the spleen and intestine of the infected zebra fish. The established zebra fish-A. sobria infection model will be valuable for elucidating the role of MR in fish immune responses to infection.

  17. First case of Aeromonas schubertii infection in the freshwater cultured snakehead fish, Ophiocephalus argus (Cantor), in China.

    Science.gov (United States)

    Liu, J Y; Li, A H

    2012-05-01

    An epizootic in snakehead fish, Ophiocephalus argus, in earthen ponds in Xianning, Hubei Province, central China, from June to August 2009 was found to be caused by Aeromonas schubertii. The cumulative mortality within 40 days was 45%, and the diseased fish were 18 months old and 35-45 cm in length. Multiple, ivory-white, firm nodules, 0.5-1 mm in diameter, were scattered throughout the kidney. Blood clots, 3-5 mm in diameter, were found in the liver. This is a disease frequently found in cultured snakehead throughout China. Isolated bacteria were Gram negative, facultatively anaerobic, motile, short rod-shaped, with a length of 0.3-1.0 μm. Morphological and biochemical tests, as well as phylogenetic analysis derived from 16S rRNA, gyrB, rpoD and dnaJ gene sequencing all strongly indicated that these snakehead isolates are identical to A. schubertii. In addition, the isolates possessed two plasmids: 5.0 kb and 10.0 kb. Antibiotic sensitivity testing of the isolates was carried out by the standard Kirby-Bauer disc diffusion method. Experimental infection assays were conducted, and pathogenicity (by intraperitoneal injection) was demonstrated in snakehead fingerlings and zebrafish, Brachydanio rerio (Hamilton).

  18. Aeromonas molluscorum Av27 is a potential tributyltin (TBT) bioremediator: phenotypic and genotypic characterization indicates its safe application.

    Science.gov (United States)

    Cruz, Andreia; Areias, Dário; Duarte, Ana; Correia, António; Suzuki, Satoru; Mendo, Sónia

    2013-09-01

    Aeromonas molluscorum Av27 is an estuarine bacterium highly resistant to tributyltin (TBT). Also, the strain is able to degrade TBT into the less toxic compounds dibutyltin and monobutyltin. Therefore, this bacterium has potential to be employed in bioremediation processes. In this context, defining its biological safety is crucial. With that purpose a number of intrinsic characteristics, usually present/associated with virulent strains, were investigated. Few virulence factors were detected in strain Av27. For instance, a DNase gene is present, but it is not apparently expressed in vitro. Motility, adherence factor and phospholipase activity were also detected. Additionally, cytotoxicity to Vero cells was negative. Resistance to penicillin (10 μg ml(-1)), amoxicillin/clavulanic acid (30 μg ml(-1)) and cephalothin (30 μg ml(-1)) and also to the vibriostatic agent O/129 was observed. Five plasmids (4, 7, 10, 100 kb and one greater than 100 kb) were identified. No Class I and II integrons were detected. Study of the optimal growth conditions showed that Av27 easily adapts to different environmental conditions. Overall, the results suggest that A. molluscorum Av27 can be considered safe to use to bioremediate TBT in contaminated environments.

  19. Protective effect of probiotic diets on haematobiochemical and histopathology changes of Mystus montanus (Jerdon 1849 against Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Gurusamy Chelladurai

    2013-11-01

    Full Text Available Objectives: To evaluate the protective effect of probiotic diets on haemotobiochemical and histopathology changes of Mystus montanus against Aeromonas hydrophila (A. hydrophila. Methods: Three experimental groups of fish were fed with a diet supplemented with Lactobacillus acidophilus (L. acidophilus (Sporolac, comprising about 0.1 g, 0.2 g and 0.3 g. Control group of fish were fed without L. acidophilus. After 60 d of feeding the fishes in experimental group were injected with 1 mL of A. hydrophila and were supplemented with probiotic diets. The control group fishes were injected with 1 mL of physiological saline solution alone. Results: Blood samples were collected for haematobiochemical analysis, while samples of the liver, and gills were examined for path histology after 7 d of infection. The result showed that the growth parameters, weight gain, specific growth rate were better in infected group maintained on the probiotic diet compared to those in control group. The haematology parameters, erythrocyte sedimentation rate, red blood cell, white blood cell, total serum protein, Mg 2+ , Ca 2+ , Cl, glucose, cholesterol and total immunoglobulin concentration and the pathohistology of the liver, gills were better in the infected fish maintained on the probiotic diet than those in the group fed the control diet. Conclusions: The result of the present study showed that L. acidophilus is useful as a probiotic agent in Mystus montanus against A. hydrophila.

  20. Molecular Cloning and Functional Characterization of Mannose Receptor in Zebra Fish (Danio rerio) during Infection with Aeromonas sobria.

    Science.gov (United States)

    Zheng, Feifei; Asim, Muhammad; Lan, Jiangfeng; Zhao, Lijuan; Wei, Shun; Chen, Nan; Liu, Xiaoling; Zhou, Yang; Lin, Li

    2015-05-15

    Mannose receptor (MR) is a member of pattern-recognition receptors (PRRs), which plays a significant role in immunity responses. Much work on MR has been done in mammals and birds while little in fish. In this report, a MR gene (designated as zfMR) was cloned from zebra fish (Danio rerio), which is an attractive model for the studies of animal diseases. The full-length cDNA of zfMR contains 6248 bp encoding a putative protein of 1428 amino acids. The predicted amino acid sequences showed that zfMR contained a cysteine-rich domain, a single fibronectin type II (FN II) domain, eight C-type lectin-like domains (CTLDs), a transmembrane domain and a short C-terminal cytoplasmic domain, sharing highly conserved structures with MRs from the other species. The MR mRNA could be detected in all examined tissues with highest level in kidney. The temporal expression patterns of MR, IL-1β and TNF-α mRNAs were analyzed in the liver, spleen, kidney and intestine post of infection with Aeromonas sobria. By immunohistochemistry assay, slight enhancement of MR protein was also observed in the spleen and intestine of the infected zebra fish. The established zebra fish-A. sobria infection model will be valuable for elucidating the role of MR in fish immune responses to infection.

  1. Edwardsiella tarda and Aeromonas hydrophila isolated from diseased Southern flounder (Paralichthys lethostigma) are virulent to channel catfish and Nile tilapia

    Institute of Scientific and Technical Information of China (English)

    Julia W Pridgeon; Phillip H Klesius; Gregory A Lewbart; Harry V Daniels; Megan Jacob

    2014-01-01

    Objective:To identify bacteria isolated from diseased Southern flounder and determine whether they are virulent to channel catfish and Nile tilapia. Methods:Gram-negative bacteria isolates were recovered from five tissues of diseased Southern flounder (Paralichthys lethostigma). The isolates were subjected to biochemical and molecular identification followed by virulence study in fish. Results: Based on biochemical analysis, the 25 isolates were found to share homologies with either Edwardsiella tarda (E. tarda) or Aeromonas hydrophila (A. hydrophila). Based on sequencing results of partial 16S rRNA gene, 15 isolates shared 100%identities with the 16S rRNA sequence of previously identified E. tarda strain TX1, whereas the other 10 isolates shared 100%identities with the 16S rRNA sequence of previously identified A. hydrophila strain An4. When healthy fish were exposed to flounder isolate by intracoelomic injection, the LD50 values of flounder isolate E. tarda to channel catfish or Nile tilapia [(10±2) g] were 6.1í104 and 1.1í107 CFU/fish, respectively, whereas that of flounder isolate A. hydrophila to channel catfish and Nile tilapia were 1.4í107 and 5.6í107 CFU/fish, respectively. Conclusions: This is the first report that E. tarda and A. hydrophila isolated from diseased Southern flounder are virulent to catfish and tilapia.

  2. Effect of acute and chronic arsenic exposure on growth, structure and virulence of Aeromonas hydrophila isolated from fish.

    Science.gov (United States)

    Goswami, Ramansu; Ghosh, Debabrata; Saha, Dhira Rani; Padhy, Pratap Kumar; Mazumder, Shibnath

    2011-02-01

    Aeromonas hydrophila being a ubiquitous bacterium is prone to arsenic exposure. The present study was designed to determine the role of arsenic on growth and virulence of A. hydrophila. Exposure to arsenic (1 mg L(-1) and 2 mg L(-1)) had no effect on growth but significantly inhibited the hemolytic and cytotoxic potential of exposed bacteria. Transmission electron microscopy revealed loss of membrane integrity and presence of condensed cytoplasm suggestive of acute stress in bacteria exposed to arsenic. Arsenic-adapted bacteria were developed by repeated sub-culturing in presence of arsenic. Arsenic-adaptation led to significant recovery in hemolytic and cytotoxic potential. The arsenic-adapted bacteria exhibited normal membrane integrity, decreased cytoplasmic condensation and possessed scattered polysome like structures in the cytoplasm. A positive correlation was observed between arsenic tolerance and resistance to several antimicrobials. Arsenic-adaptation failed to confer cross-protection to mercury and cadmium stress. SDS-PAGE analysis revealed the expression of two new proteins of approximately 85 kDa and 79 kDa respectively in arsenic-adapted A. hydrophila. Plasmid-curing and transformation studies clearly indicate plasmid has no role on arsenic resistance trait of the bacteria. Our study, for the first time, reports a structure and function relationship of xenobiotics on bacteria.

  3. Effect of Lactobacillus plantarum C014 on Innate Immune Response and Disease Resistance against Aeromonas hydrophila in Hybrid Catfish

    Directory of Open Access Journals (Sweden)

    Sureerat Butprom

    2013-01-01

    Full Text Available A bacterial strain isolated from intestines of hybrid catfish (Clarias gariepinus Male × Clarias macrocephalus Female exhibited an in vitro inhibitory effect on a fish pathogen, Aeromonas hydrophila TISTR 1321. By using the 16S rDNA sequence analysis, it was identified as Lactobacillus plantarum C014. To examine whether L. plantarum C014 had potential for use as an immunostimulant and biocontrol agent in hybrid catfish, the fish diet supplemented with L. plantarum C014 (107 CFU/g diet was prepared and used for the in vivo investigation of its effect on innate immune response and disease resistance of hybrid catfish. Two innate immune response parameters, phagocytic activity of blood leukocytes and plasma lysozyme activity, were significantly enhanced in the treated fish after 45 days of feeding. Feeding the fish with the L. plantarum C014 supplemented diet for 45 days before challenging them with A. hydrophila at the dose of LD50 could reduce the mortality rate of the fish from 50% (in control group to 0% (in treated group. Based on its origin and beneficial effect on innate immune response and disease resistance, L. plantarum C014 may be a potential candidate for use as a natural and safe immunostimulant and biocontrol agent in hybrid catfish.

  4. Hesperidin Inhibits Inflammatory Response Induced by Aeromonas hydrophila Infection and Alters CD4+/CD8+ T Cell Ratio

    Directory of Open Access Journals (Sweden)

    Abdelaziz S. A. Abuelsaad

    2014-01-01

    Full Text Available Background. Aeromonas hydrophila is an opportunistic bacterial pathogen that is associated with a number of human diseases. Hesperidin (HES has been reported to exert antioxidant and anti-inflammatory activities. Objectives. The aim of this study was to investigate the potential effect of HES treatment on inflammatory response induced by A. hydrophila infection in murine. Methods. A. hydrophila-infected mice were treated with HES at 250 mg/kg b.wt./week for 4 consecutive weeks. Phagocytosis, reactive oxygen species production, CD4+/CD8+ T cell ratio, and CD14 expression on intestinal infiltrating monocytes were evaluated. The expression of E-selectin and intercellular adhesion molecule 1 on stimulated HUVECs and RAW macrophage was evaluated. Results. Percentage of CD4+ T cells in the intestinal tissues of infected treated mice was highly significantly increased; however, phagocytic index, ROS production, CD8+ T cells percentage, and CD14 expression on monocytes were significantly reduced. On the other hand, HES significantly inhibited A-LPS- and A-ECP-induced E-selectin and ICAM-1 expression on HUVECs and ICAM-1 expression on RAW macrophage. Conclusion. Present data indicated that HES has a potential role in the suppression of inflammatory response induced by A. hydrophila toxins through downmodulation of ROS production and CD14 and adhesion molecules expression, as well as increase of CD4+/CD8+ cell ratio.

  5. Influence of clove oil on certain quorum-sensing-regulated functions and biofilm of Pseudomonas aeruginosa and Aeromonas hydrophila

    Indian Academy of Sciences (India)

    Fohad Mabood Husain; Iqbal Ahmad; Mohammad Asif; Qudsia Tahseen

    2013-12-01

    Quorum sensing (QS) plays an important role in virulence, biofilm formation and survival of many pathogenic bacteria including Pseudomonas aeruginosa. This signalling pathway is considered as novel and promising target for anti-infective agents. In the present investigation, effect of the Sub-MICs of clove oil on QS regulated virulence factors and biofilm formation was evaluated against P. aeruginosa PAO1 and Aeromonas hydrophila WAF-38 strain. Sub-inhibitory concentrations of the clove oil demonstrated statistically significant reduction of las- and rhl-regulated virulence factors such as LasB, total protease, chitinase and pyocyanin production, swimming motility and exopolysaccharide production. The biofilm forming capability of PAO1 and A. hydrophila WAF-38 was also reduced in a concentration-dependent manner at all tested sub-MIC values. Further, the PAO1-preinfected Caenorhabditis elegans displayed an enhanced survival when treated with 1.6% v/v of clove oil. The above findings highlight the promising anti-QS-dependent therapeutic function of clove oil against P. aeruginosa.

  6. Analysis and Validation of a Predictive Model for Growth and Death of Aeromonas hydrophila under Modified Atmospheres at Refrigeration Temperatures

    Science.gov (United States)

    Pin, Carmen; Velasco de Diego, Raquel; George, Susan; García de Fernando, Gonzalo D.; Baranyi, József

    2004-01-01

    Specific growth and death rates of Aeromonas hydrophila were measured in laboratory media under various combinations of temperature, pH, and percent CO2 and O2 in the atmosphere. Predictive models were developed from the data and validated by means of observations obtained from (i) seafood experiments set up for this purpose and (ii) the ComBase database (http://www.combase.cc; http://wyndmoor.arserrc.gov/combase/).Two main reasons were identified for the differences between the predicted and observed growth in food: they were the variability of the growth rates in food and the bias of the model predictions when applied to food environments. A statistical method is presented to quantitatively analyze these differences. The method was also used to extend the interpolation region of the model. In this extension, the concept of generalized Z values (C. Pin, G. García de Fernando, J. A. Ordóñez, and J. Baranyi, Food Microbiol. 18:539-545, 2001) played an important role. The extension depended partly on the density of the model-generating observations and partly on the accuracy of extrapolated predictions close to the boundary of the interpolation region. The boundary of the growth region of the organism was also estimated by means of experimental results for growth and death rates. PMID:15240265

  7. Inhibitory activity of monoacylglycerols on biofilm formation in Aeromonas hydrophila, Streptococcus mutans, Xanthomonas oryzae, and Yersinia enterocolitica.

    Science.gov (United States)

    Ham, Youngseok; Kim, Tae-Jong

    2016-01-01

    Biofilm provides a bacterial hiding place by forming a physical barrier and causing physiological changes in cells. The elimination of biofilm is the main goal of hygiene. Chemicals that are inhibitory to biofilm formation have been developed for use in food, personal hygiene products, and medical instruments. Monoacylglycerols are recognized as safe and are used in food as emulsifiers. In this study, the inhibitory activity of monoacylglycerols on bacterial biofilm formation was evaluated systematically with four bacterial strains, Aeromonas hydrophila, Streptococcus mutans, Xanthomonas oryzae, and Yersinia enterocolitica. Monoacylglycerols with two specific lengths of fatty acid moiety, monolaurin and monobehenin, were found to have strong inhibitory activity toward bacterial biofilm formation of S. mutans, X. oryzae, and Y. enterocolitica in a strain specific manner. First, this result suggested that biofilm formation was not inhibited by the detergent characteristics of monoacylglycerols. This suggestion was supported by the inhibitory action of monolaurin on biofilm development but not on the initial cell attachment of Y. enterocolitica in flow cytometric observation. Second, it was also suggested that two distinct response mechanisms to monoacylglycerols existed in bacteria. The existence of these two inhibitory response mechanisms was bacterial strain specific.

  8. Single-walled carbon nanotubes as delivery vehicles enhance the immunoprotective effects of a recombinant vaccine against Aeromonas hydrophila.

    Science.gov (United States)

    Gong, Yu-Xin; Zhu, Bin; Liu, Guang-Lu; Liu, Lei; Ling, Fei; Wang, Gao-Xue; Xu, Xin-Gang

    2015-01-01

    To reduce the economic losses caused by diseases in aquaculture industry, more efficient and economic prophylactic measures should be urgently investigated. In this research, the effects of a novel functionalized single-walled carbon nanotubes (SWCNTs) applied as a delivery vehicle for recombinant Aeromonas hydrophila vaccine administration via bath or injection in juvenile grass carp were studied. The results showed that SWCNT as a vector for the recombinant protein aerA, augmented the production of specific antibodies, apparently stimulated the induction of immune-related genes, and induced higher level of survival rate compared with free aerA subunit vaccine. Furthermore, we compared the routes of bath and intramuscular injection immunization by SWCNTs-aerA vaccine, and found that similar antibody levels induced by SWCNTs-aerA were observed in both immunization routes. Meanwhile, a similar relative percentage survival (approximately 80%) was found in both a 40 mg/L bath immunization group, and a 20 μg injection group. The results indicate that functionalized SWCNTs could be a promising delivery vehicle to potentiate the immune response of recombinant vaccines, and might be used to vaccinate juvenile fish by bath administration method.

  9. Pharmacokinetic/pharmacodynamic relationship of marbofloxacin against Aeromonas hydrophila in Chinese soft-shelled turtles (Trionyx sinensis).

    Science.gov (United States)

    Shan, Q; Zheng, G; Liu, S; Bai, Y; Li, L; Yin, Y; Ma, L; Zhu, X

    2015-12-01

    The single-dose disposition kinetics of the antibiotic marbofloxacin were determined in Chinese soft-shelled turtles (n = 10) after oral and intramuscular (i.m.) dose of 10 mg/kg bodyweight. The in vitro and ex vivo activities of marbofloxacin in serum against a pathogenic strain of Aeromonas hydrophila were determined. A concentration-dependent antimicrobial activity of marbofloxacin was confirmed for levels lower than 4 × MIC. For in vivo PK data, values of AUC: minimum inhibitory concentration (MIC) ratio for serum were 1166.6 and 782.4 h, respectively, after i.m. and oral dosing of marbofloxacin against a pathogenic strain of A. hydrophila (MIC = 0.05 μg/mL). The ex vivo growth inhibition data after oral dosing were fitted to the inhibitory sigmoid Emax equation to provide the values of AUC/MIC required to produce bacteriostasis, bactericidal activity and elimination of bacteria. The respective values were 23.79, 36.35 and 126.46 h. It is proposed that these findings might be used with MIC50 or MIC90 data to provide a rational approach to the design of dosage schedules, which optimize efficacy in respect of bacteriological as well as clinical cures.

  10. Comparative evaluation of infection methods and environmental factors on challenge success: Aeromonas salmonicida infection in vaccinated rainbow trout.

    Science.gov (United States)

    Chettri, Jiwan Kumar; Skov, Jakob; Jaafar, Rzgar M; Krossøy, Bjørn; Kania, Per W; Dalsgaard, Inger; Buchmann, Kurt

    2015-06-01

    When testing vaccine-induced protection an effective and reliable challenge method is a basic requirement and we here present a comparative study on different challenge methods used for infection of rainbow trout Oncorhynchus mykiss with Aeromonas salmonicida, a bacterial pathogen eliciting furunculosis. Fish were vaccinated with three different adjuvanted trivalent vaccines containing formalin killed A. salmonicida, Vibrio anguillarum O1 and O2a. These were 1) the commercial vaccine Alpha Ject 3000, 2) an experimental vaccine with water in paraffin oil adjuvant, 3) an experimental vaccine with water in paraffin oil in water adjuvant. Fish were then exposed to A. salmonicida challenge using i.p. injection, cohabitation in freshwater, cohabitation in saltwater (15 ppt) or combined fresh/saltwater cohabitation. Cohabitation reflects a more natural infection mode and was shown to give better differentiation of vaccine types compared to i.p. injection of live bacteria. The latter infection mode is less successful probably due to the intra-abdominal inflammatory reactions (characterized in this study according to the Speilberg scale) induced by i.p. vaccination whereby injected live bacteria more effectively become inactivated at the site of injection. Compared to cohabitation in freshwater, cohabitation in saltwater was less efficient probably due to reduced survivability of A. salmonicida in saltwater, which was also experimentally verified in vitro.

  11. Identification and Characterization of MicroRNAs in the Liver of Blunt Snout Bream (Megalobrama amblycephala) Infected by Aeromonas hydrophila

    Science.gov (United States)

    Cui, Lei; Hu, Hongtao; Wei, Wei; Wang, Weimin; Liu, Hong

    2016-01-01

    MicroRNAs (miRNAs) are small RNA molecules that play key roles in regulation of various biological processes. In order to better understand the biological significance of miRNAs in the context of Aeromonas hydrophila infection in Megalobrama amblycephala, small RNA libraries obtained from fish liver at 0 (non-infection), 4, and 24 h post infection (poi) were sequenced using Illumina deep sequencing technology. A total of 11,244,207, 9,212,958, and 7,939,157 clean reads were obtained from these three RNA libraries, respectively. Bioinformatics analysis identified 171 conserved miRNAs and 62 putative novel miRNAs. The existence of ten randomly selected novel miRNAs was validated by RT-PCR. Pairwise comparison suggested that 61 and 44 miRNAs were differentially expressed at 4 and 24 h poi, respectively. Furthermore, the expression profiles of nine randomly selected miRNAs were validated by qRT-PCR. MicroRNA target prediction, gene ontology (GO) annotation, and Kyoto Encylopedia of Genes and Genomes (KEGG) analysis indicated that a variety of biological pathways could be affected by A. hydrophila infection. Additionally, transferrin (TF) and transferrin receptor (TFR) genes were confirmed to be direct targets of miR-375. These results will expand our knowledge of the role of miRNAs in the immune response of M. amblycephala to A. hydrophila infection, and facilitate the development of effective strategies against A. hydrophila infection in M. amblycephala. PMID:27898025

  12. Identification and Characterization of MicroRNAs in the Liver of Blunt Snout Bream (Megalobrama amblycephala Infected by Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Lei Cui

    2016-11-01

    Full Text Available MicroRNAs (miRNAs are small RNA molecules that play key roles in regulation of various biological processes. In order to better understand the biological significance of miRNAs in the context of Aeromonas hydrophila infection in Megalobrama amblycephala, small RNA libraries obtained from fish liver at 0 (non-infection, 4, and 24 h post infection (poi were sequenced using Illumina deep sequencing technology. A total of 11,244,207, 9,212,958, and 7,939,157 clean reads were obtained from these three RNA libraries, respectively. Bioinformatics analysis identified 171 conserved miRNAs and 62 putative novel miRNAs. The existence of ten randomly selected novel miRNAs was validated by RT-PCR. Pairwise comparison suggested that 61 and 44 miRNAs were differentially expressed at 4 and 24 h poi, respectively. Furthermore, the expression profiles of nine randomly selected miRNAs were validated by qRT-PCR. MicroRNA target prediction, gene ontology (GO annotation, and Kyoto Encylopedia of Genes and Genomes (KEGG analysis indicated that a variety of biological pathways could be affected by A. hydrophila infection. Additionally, transferrin (TF and transferrin receptor (TFR genes were confirmed to be direct targets of miR-375. These results will expand our knowledge of the role of miRNAs in the immune response of M. amblycephala to A. hydrophila infection, and facilitate the development of effective strategies against A. hydrophila infection in M. amblycephala.

  13. Recovery of a fish pathogenic bacterium, Aeromonas salmonicida, from ebonyshell mussels Fusconaia ebena using nondestructive sample collection procedures

    Science.gov (United States)

    Starliper, C.E.

    2008-01-01

    Refugia are increasingly being used to maintain and propagate imperiled freshwater mussels for future population augmentations. Success for this endeavor is dependent on good husbandry, including a holistic program of resource health management. A significant aspect to optimal health is the prevention or control of infectious diseases. Describing and monitoring pathogens and diseases in mussels involves examination of tissues or samples collected from an appropriate number of individuals that satisfies a certain confidence level for expected prevalences of infections. In the present study, ebonyshell mussels Fusconaia ebena were infected with a fish pathogenic bacterium, Aeromonas salmonicida, through their cohabitation with diseased brook trout Salvelinus fontinalis. At a 100% prevalence of infection, the F. ebena were removed from the cohabitation tank to clean tanks that were supplied with pathogen-free water, which initiated their depuration of A. salmonicida. Three samples (nondestructive fluid, mantle, hemolymph) collected using nondestructive procedures were compared with fluids and soft tissue homogenates collected after sacrificing the mussels for recovery of the bacterium during this period of depuration. Nondestructive sample collections, especially ND fluid, provide a comparable alternative to sacrificing mussels to determine pathogen status.

  14. Identification of Aeromonas hydrophila Genes Preferentially Expressed after Phagocytosis by Tetrahymena and Involvement of Methionine Sulfoxide Reductases

    Science.gov (United States)

    Pang, Maoda; Lin, Xiaoqin; Liu, Jin; Guo, Changming; Gao, Shanshan; Du, Hechao; Lu, Chengping; Liu, Yongjie

    2016-01-01

    Free-living protozoa affect the survival and virulence evolution of pathogens in the environment. In this study, we explored the fate of Aeromonas hydrophila when co-cultured with the bacteriovorous ciliate Tetrahymena thermophila and investigated bacterial gene expression associated with the co-culture. Virulent A. hydrophila strains were found to have ability to evade digestion in the vacuoles of this protozoan. In A. hydrophila, a total of 116 genes were identified as up-regulated following co-culture with T. thermophila by selective capture of transcribed sequences (SCOTS) and comparative dot-blot analysis. A large proportion of these genes (42/116) play a role in metabolism, and some of the genes have previously been characterized as required for bacterial survival and replication within macrophages. Then, we inactivated the genes encoding methionine sulfoxide reductases, msrA, and msrB, in A. hydrophila. Compared to the wild-type, the mutants ΔmsrA and ΔmsrAB displayed significantly reduced resistance to predation by T. thermophila, and 50% lethal dose (LD50) determinations in zebrafish demonstrated that both mutants were highly attenuated. This study forms a solid foundation for the study of mechanisms and implications of bacterial defenses. PMID:28083518

  15. Survival of Vibrio parahaemolyticus and Aeromonas hydrophila in sea bream (Sparus aurata) fillets packaged under enriched CO(2) modified atmospheres.

    Science.gov (United States)

    Provincial, Laura; Guillén, Elena; Alonso, Verónica; Gil, Mario; Roncalés, Pedro; Beltrán, José A

    2013-08-16

    The ability to survive of two pathogens (Vibrio parahaemolyticus and Aeromonas hydrophila) spread over sea bream fillets packaged under different modified atmospheres (MAPs) was studied at 0°C and 4°C under refrigerated storage. The atmospheres used were 60% CO2/40% N2, 70% CO2/30% N2 and 80% CO2/20% N2 and a control batch packaged in air. Head space gas analyses, microbial counts and confirming test of pathogenic bacteria were carried out during 16days. The results obtained showed that all the modified atmospheres studied were effective to reduce the microbial load of sea bream fillets when compared with air packaged samples although small differences were found among MAPs. Temperature storage was the main factor to reduce microbial growth. V. parahaemolyticus was unable to grow at both temperatures, 0°C and 4°C (except air batches) while A. hydrophila showed significant growth at 4°C and microbial inactivation at 0°C.

  16. Protective effect of probiotic diets on haematobiochemical and histopathology changes of Mystus montanus (Jerdon 1849) against Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    Gurusamy Chelladurai; Jebaraj Felicitta; Rathinasami Nagarajan

    2013-01-01

    Objectives: To evaluate the protective effect of probiotic diets on haemotobiochemical histopathology changes of Mystus montanus against Aeromonas hydrophila (A. hydrophila). and Methods: Three experimental groups of fish were fed with a diet supplemented with Lactobacillus acidophilus (L. acidophilus) (Sporolac), comprising about 0.1 g, 0.2 g and 0.3 g. Control group of fiinsjhe cwteedre wfeitdh w1i tmhoLu ot fL A. .a chiyddorpohpihluilsa. Aafntedr w60e rde osfu pfepeldeimnge nttheed fiwshitehs pinro ebxiopteirci mdieenttsa.l Tghroeu cpo nwterroel group fishes were injected with 1 mL of physiological saline solution alone. Results: Blood samples were collected for haematobiochemical analysis, while samples of the lgirvoewr,t ha npda rgaimllse tweresr,e w eexiagmhti ngeadin f,o srp peactihfi ch igsrtoowlotghy raafttee rw 7e rde obfe itntefer citnio inn.f eTchtee dr egsruolut ps hmoawiendta tihnaetd t hone stheed ipmreonbtiaottiiocn d rieatt ec, ormedp abrleodo dto c tehlol,s ew hinit ec obnlotroodl gcreollu,p t.o tTahl es ehrauemm aptrooltoegiyn ,p Marga2m+, eCtear2+s,, Celr,y gthluroccoystee, cbheottleers tienr othl ea nindf etocttaeld i mfismh umnaoignlotabiunleidn ocnon tcheen ptrraotbioiont iacn ddi etht eth paant hthohosiset oinlo tghye o gf rtohuep l ifveedr ,t hgeil lcso wnterroel diet. Conclusions: The result of the present study showed that L. acidophilus is useful as a probiotic agent in Mystus montanus against A. hydrophila.

  17. The cytotoxic effect of essential oils from Origanum vulgare L. and/or Rosmarinus officinalis L. on Aeromonas hydrophila.

    Science.gov (United States)

    Azerêdo, Geíza Alves de; Stamford, Tânia Lúcia Montenegro; Figueiredo, Regina Celia Bressan Queiroz de; Souza, Evandro Leite de

    2012-04-01

    This study aimed to evaluate the antibacterial activities of the essential oils from Origanum vulgare L. (OV) and Rosmarinus officinalis L. (RO), both singly and in combination at sub-inhibitory concentrations (¼ MIC + ¼ MIC), against Aeromonas hydrophila and to investigate the possible mechanisms underlying these activities. Used singly (OV: 2.5 μL/mL; RO: 20 μL/mL) or in a mixture (OV: 0.625 μL/mL + RO: 5 μL/L), these essential oils led to a significant decrease (p<0.01) in bacterial viability after 24 h of exposure. A decrease in glucose consumption by A. hydrophila and release of cellular material were observed immediately after the addition of the essential oils, both singly and as a mixture, and continued for up to 6 h. Electron microscopy of cells exposed to the essential oils revealed severe changes in the plasma membrane, cytoplasmic appearance, and cell shape during the 6-h exposure period. OV and RO essential oils combined at sub-inhibitory concentrations could be rationally applied to inhibit the growth of A. hydrophila in food products, particularly minimally processed vegetables.

  18. Immunomodulatory effect of Withania somnifera supplementation diet in the giant freshwater prawn Macrobrachium rosenbergii (de Man) against Aeromonas hydrophila.

    Science.gov (United States)

    Harikrishnan, Ramasamy; Balasundaram, Chellam; Jawahar, Sundaram; Heo, Moon-Soo

    2012-01-01

    The effect of Withania somnifera extract supplementation diets on innate immune response in giant freshwater prawn Macrobrachium rosenbergii (de Man) against Aeromonas hydrophila was investigated. The bacterial clearance efficiency significantly increased in prawn fed with 0.1% and 1.0% doses of W. somnifera supplementation diet against pathogen from weeks 1-4 as compared to the control. The innate immune parameters such as, phenoloxidase activity, superoxide anion level, superoxide dismutase activity, nitrate, and nitrite concentrations were significantly enhanced in prawn fed with 0.1% and 1.0% doses of W. somnifera supplementation diet from weeks 1-4 against pathogen. The total hemocyte counts (THC) significantly increased in prawn fed with 0.1% and 1.0% doses diet from weeks 1-4 against pathogen as compared to the control. These results strongly suggested that administration of W. somnifera through supplementation diet positively enhances the innate immune system and enhanced survival rate in M. rosenbergii against A. hydrophila infection.

  19. Production of Poly(3-Hydroxybutyrate-co-3-Hydroxyhexanoate) Using Aeromonas hydrophila 4AK4 Grown in Mixed Carbon Source

    Institute of Scientific and Technical Information of China (English)

    张瑾; 张广; 陈金春; 华秀英; 陈国强

    2002-01-01

    Aeromonas hydrophila 4AK4 was grown on mixed substrates of soybean oil and lauric acid for the production of polyhydroxyalkanoate copolymer consisting of 3-hydroxybutyrate (3HB) and 3-hydroxyhexanoate (3HHx). A maximal poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) content of 49.13% in dry cells was obtained in a shake flask culture. PHBHHx of 6.26 -g/L was produced in a fermentation experiment over 48 -h on a sole carbon source containing 100 -g/L soybean oil, while 12.40 -g/L PHBHHx was produced on a mixed carbon source containing 80 -g/L soybean and 20 g/L lauric acid over the same period of time, resulting in a polyhydroxyalkanoate (PHA) productivity of 0.25 -g/(L*h). The results show that mixed carbon sources are suitable for industrialized production of PHBHHx from A. hydrophila 4AK4, as the mixed carbon sources also overcome the foaming problem that occurs when lauric acid is employed as a sole carbon source in PHBHHx production.

  20. Cross-talk among flesh-eating Aeromonas hydrophila strains in mixed infection leading to necrotizing fasciitis.

    Science.gov (United States)

    Ponnusamy, Duraisamy; Kozlova, Elena V; Sha, Jian; Erova, Tatiana E; Azar, Sasha R; Fitts, Eric C; Kirtley, Michelle L; Tiner, Bethany L; Andersson, Jourdan A; Grim, Christopher J; Isom, Richard P; Hasan, Nur A; Colwell, Rita R; Chopra, Ashok K

    2016-01-19

    Necrotizing fasciitis (NF) caused by flesh-eating bacteria is associated with high case fatality. In an earlier study, we reported infection of an immunocompetent individual with multiple strains of Aeromonas hydrophila (NF1-NF4), the latter three constituted a clonal group whereas NF1 was phylogenetically distinct. To understand the complex interactions of these strains in NF pathophysiology, a mouse model was used, whereby either single or mixed A. hydrophila strains were injected intramuscularly. NF2, which harbors exotoxin A (exoA) gene, was highly virulent when injected alone, but its virulence was attenuated in the presence of NF1 (exoA-minus). NF1 alone, although not lethal to animals, became highly virulent when combined with NF2, its virulence augmented by cis-exoA expression when injected alone in mice. Based on metagenomics and microbiological analyses, it was found that, in mixed infection, NF1 selectively disseminated to mouse peripheral organs, whereas the other strains (NF2, NF3, and NF4) were confined to the injection site and eventually cleared. In vitro studies showed NF2 to be more effectively phagocytized and killed by macrophages than NF1. NF1 inhibited growth of NF2 on solid media, but ExoA of NF2 augmented virulence of NF1 and the presence of NF1 facilitated clearance of NF2 from animals either by enhanced priming of host immune system or direct killing via a contact-dependent mechanism.

  1. Comparative study of semi-specific Aeromonas hydrophila and universal Pseudomonas fluorescens biosensors for BOD measurements in meat industry wastewaters.

    Science.gov (United States)

    Raud, Merlin; Tenno, Toomas; Jõgi, Eerik; Kikas, Timo

    2012-04-01

    Aeromonas hydrophila P69.1 (A. hydrophila) was used to construct a semi-specific biosensor to estimate biochemical oxygen demand (BOD) in high fat and grease content wastewaters. A. hydrophila cells were grown in fat containing medium to induce necessary enzymes for transport and degradation of fatty substances. Universal biosensor based on non-specific Pseudomonas fluorescens P75 (P. fluorescens) was used to conduct comparison experiments. Biosensors were calibrated using OECD synthetic wastewater and steady-state method, subsequently several experiments with synthetic and industrial wastewaters were conducted. A linear range up to 45 mg l(-1) BOD(7) was gained using A. hydrophila biosensor, in comparison to 40 mg l(-1) BOD(7) obtained using P. fluorescens biosensors. The lower limit of detection was 5 mg l(-1) BOD(7). Service life of A. hydrophila and P. fluorescens biosensors were 110 and 115 days, respectively. The response time of the biosensors depended on the BOD(7) of measuring solution and was up to 20 min when analyzing different wastewaters. Both biosensors underestimated BOD in meat industry wastewater from 43% up to 71%, but more accurate results could be obtained with A. hydrophila biosensor. Semi-specific A. hydrophila biosensor was able to measure proportion of fat found in wastewater sample, while other refractory compounds remained undetectable to both biosensors.

  2. Transcription factor T-bet in Atlantic salmon: Characterization and gene expression in mucosal tissues during Aeromonas salmonicida infection

    Directory of Open Access Journals (Sweden)

    Jaya eKumari

    2015-07-01

    Full Text Available The T-box transcription factor T-bet is expressed in a number of hematopoietic cell types in mammals and plays an essential role in the lineage determination of Th1 T-helper cells and is considered as an essential feature for both innate and adaptive immune responses in higher vertebrates. In the present study, we have identified and characterized the full-length Atlantic salmon T-bet cDNA (3502 bp. The putative primary structure of the polypeptide deduced from the cDNA sequence contained 612 aa, which possessed a T-box DNA binding domain. Phylogenetic study and gene synteny revealed it is a homologue to mammalian T-bet. Quantitative PCR analysis of different tissues in healthy fish showed that salmon T-bet gene was highly expressed in spleen, followed by head kidney, and was expressed in intestine, skin, and liver at lower levels. Moreover, the time dependent expression profile of T-bet, interferon gamma (IFNγ, interleukin-22 (IL-22, and NKEF (Natural killer enhancement factor in mucosal tissues during waterborne infection with live Aeromonas salmonicida, indicated the involvement of T-bet in mucosal immune response in Atlantic salmon.

  3. Occurrence of bacteriophages infecting Aeromonas, Enterobacter, and Klebsiella in water and association with contamination sources in Thailand.

    Science.gov (United States)

    Wangkahad, Bencharong; Bosup, Suchada; Mongkolsuk, Skorn; Sirikanchana, Kwanrawee

    2015-06-01

    The co-residence of bacteriophages and their bacterial hosts in humans, animals, and environmental sources directed the use of bacteriophages to track the origins of the pathogenic bacteria that can be found in contaminated water. The objective of this study was to enumerate bacteriophages of Aeromonas caviae (AecaKS148), Enterobacter sp. (EnspKS513), and Klebsiella pneumoniae (KlpnKS648) in water and evaluate their association with contamination sources (human vs. animals). Bacterial host strains were isolated from untreated wastewater in Bangkok, Thailand. A double-layer agar technique was used to detect bacteriophages. All three bacteriophages were detected in polluted canal samples, with likely contamination from human wastewater, whereas none was found in non-polluted river samples. AecaKS148 was found to be associated with human fecal sources, while EnspKS513 and KlpnKS648 seemed to be equally prevalent in both human and animal fecal sources. Both bacteriophages were also present in polluted canals that could receive contamination from other fecal sources or the environment. In conclusion, all three bacteriophages were successfully monitored in Bangkok, Thailand. This study provided an example of bacteriophages for potential use as source identifiers of pathogen contamination. The results from this study will assist in controlling sources of pathogen contamination, especially in developing countries.

  4. Transcriptional profiles of multiple genes in the anterior kidney of channel catfish vaccinated with an attenuated Aeromonas hydrophila.

    Science.gov (United States)

    Mu, Xingjiang; Pridgeon, Julia W; Klesius, Phillip H

    2011-12-01

    A total of 22 uniquely expressed sequence tags (ESTs) were identified from channel catfish anterior kidney subtractive cDNA library at 12 h post vaccination with an attenuated Aeromonas hydrophila (AL09-71 N+R). Of the 22 ESTs, six were confirmed to be significantly (P < 0.05) induced by the vaccination. Of 88 channel catfish genes selected from literature, 14 were found to be significantly (P < 0.05) upregulated by the vaccination. The transcriptional levels of the total 20 genes induced by the vaccination were then compared to that induced by the virulent parent A. hydrophila (AL09-71) at different time points. At 3 h post vaccination (hpv) or infection (hpi), Na(+)/K(+) ATPase α subunit was upregulated the most. At 6 and 12 hpv or hpi, hepcidin and interleukin-1β were induced the highest. At 24 hpv or hpi, hepcidin was upregulated the most, followed by lysozyme c. At 48 hpi, lysozyme c and hepcidin were significantly induced. When vaccinated fish were challenged by AL09-71, relative percent of survival of vaccinated fish were 100% at 14 days post vaccination (dpv). Transcriptional levels of toll-like receptor 5 and hepcidin were significantly upregulated in vaccinated fish at 14 dpv. Taken together, our results suggest that vaccination with attenuated A. hydrophila mimics infection by live bacteria, inducing multiple immune genes in channel catfish.

  5. A multi-approach study of influence of growth temperature and nutrient deprivation in a strain of Aeromonas hydrophila.

    Science.gov (United States)

    Bruscolini, Francesca; Barbieri, Federica; Battistelli, Michela; Betti, Michele; Dominici, Sabrina; Manti, Anita; Boi, Paola; Marinelli, Francesco; Papa, Stefano; Pianetti, Anna

    2014-10-01

    In the present study we investigated the behavior of an Aeromonas hydrophila strain in prolonged nutrient deprivation condition analyzing the possible link among survival, cell morphology and adhesive characteristics and correlating them with the expression of the 43kDa outer membrane protein (OMP). The strain was inoculated in mineral and drinking chlorinated water, and in Nutrient Broth as a control with incubation at 4 and 24°C for 176days. Specimens were analyzed at different times during starvation stress. Viability was assessed by flow cytometry and growth by plate count technique; morphology and adhesivity were detected by optical and electron microscopy. The 43kDa OMP expression at different times was determined after immunoblotting assay using a polyclonal antibody produced in rabbit. The results showed a long-term viability as evidenced by cytofluorimetric analysis; however, the prolonged starvation led to the shift from the normal rod shaped cells to spherical forms in the last phases of incubation especially at 24°C. Concomitantly with the appearance of spherical cells we noted a reduction of the 43kDa OMP content and adhesive ability. Therefore, our results suggest a role of the 43kDa OMP as adhesin in A. hydrophila. In conclusion, we demonstrated that the bacterium can long survive under stress conditions, however adopting strategies which can lead to a loss of some cell surface components involved in the interactions with eukaryotic cells, therefore modifying its virulence properties.

  6. Polar Glycosylated and Lateral Non-Glycosylated Flagella from Aeromonas hydrophila Strain AH-1 (Serotype O11

    Directory of Open Access Journals (Sweden)

    Kelly M. Fulton

    2015-11-01

    Full Text Available Polar and but not lateral flagellin proteins from Aeromonas hydrophila strain AH-1 (serotype O11 were found to be glycosylated. Top-down mass spectrometry studies of purified polar flagellins suggested the presence of a 403 Da glycan of mass. Bottom-up mass spectrometry studies showed the polar flagellin peptides to be modified with 403 Da glycans in O-linkage. The MS fragmentation pattern of this putative glycan was similar to that of pseudaminic acid derivative. Mutants lacking the biosynthesis of pseudaminic acid (pseB and pseI homologues were unable to produce polar flagella but no changes were observed in lateral flagella by post-transcriptional regulation of the flagellin. Complementation was achieved by reintroduction of the wild-type pseB and pseI. We compared two pathogenic features (adhesion to eukaryotic cells and biofilm production between the wild-type strain and two kinds of mutants: mutants lacking polar flagella glycosylation and lacking the O11-antigen lipopolysaccharide (LPS but with unaltered polar flagella glycosylation. Results suggest that polar flagella glycosylation is extremely important for A. hydrophila AH-1 adhesion to Hep-2 cells and biofilm formation. In addition, we show the importance of the polar flagella glycosylation for immune stimulation of IL-8 production via toll-“like” receptor 5 (TLR5.

  7. Antimicrobial susceptibility, hemolysis, and hemagglutination among Aeromonas spp. isolated from water of a bovine abattoir Perfil de resistência/sensibilidade e virulência de espécies de Aeromonas isoladas de amostras de água obtidas em abatedouro bovino

    Directory of Open Access Journals (Sweden)

    Delmar Bizani

    2001-12-01

    Full Text Available The presence of Aeromonas spp. in food has been demonstrated. They are often introduced from water, which is the natural habitat of many species and is thought to be the main source of contamination. The occurrence of Aeromonas spp. was investigated in 70 water samples of a bovine abattoir. Aeromonas spp. were present in 21.4% of water samples. A. hydrophila was isolated from 11.4% of supplying water samples and from 25.7% of the water drained from carcasses, whereas A. sobria was sole isolated from 5.7% of supplying water samples. Although greater number of positive samples were from water drained from carcasses, only A. hydrophila isolates were present. This suggests that the supplying water is the source of contamination. The antibiotic susceptibility testing revealed all strains were resistant to b-lactam antibiotics. However, the susceptibility to other antimicrobials was variable, being A. hydrophila more resistant than A. sobria strains. The investigation for virulence factors revealed positive reactions of hemolysis and hemagglutination. The results indicate that Aeromonas spp. are present in the supplying water system. These microorganisms may be a potential contaminant of carcasses and widespread in derived food.A presença de bactérias do gênero Aeromonas nos alimentos tem sido demonstrada. Normalmente destacam-se os alimentos que durante sua industrialização entraram em contato com a água, a qual é tida como habitat natural das diversas espécies e principal fonte de contaminação. Objetivando determinar a ocorrência de espécies de Aeromonas, bem como aspectos relacionados a sua virulência como capacidade de hemólise e hemoaglutinação, foram analisadas 70 amostras de água divididas entre água de abastecimento e de escoamento de lavagem das carcaças. De acordo com os resultados obtidos verificou-se a ocorrência de Aeromonas spp. em 21,4% das amostras. A. hydrophila obteve o maior índice de isolamento, 11,4% em

  8. Total protein electrophoresis and RAPD fingerprinting analysis for the identification of Aeromonas at the species level Análise eletroforética de proteínas totais e marcadores de RAPD na identificação de Aeromonas ao nível de espécie

    Directory of Open Access Journals (Sweden)

    Ana Paula Longaray Delamare

    2002-12-01

    Full Text Available Fifteen well-defined strains of Aeromonas of thirteen species were analyzed by SDS protein electrophoretic analysis (SDS-PAGE and random amplified polymorphic DNA analysis (RAPD. The comparison between the patterns obtained by both methods allowed differentiating all the strains. Clusters formed by the unweighted pair group method with arithmetic averages applied to protein data correlates with the genetic and biochemical information about the species. The results show that protein fingerprinting has the potential to differentiate Aeromonas species, but the low qualitative variation indicates that this technique is not efficient for the characterization of strains within a species. Conversely, RAPD fingerprinting allows the identification of strains but the high variability limits its potential as an aiding method for species identification.Quinze linhagens de Aeromonas pertencentes a treze espécies foram avaliadas através de eletroforese de proteínas totais (SDS-PAGE e segmentos de DNA amplificados ao acaso (RAPD. A comparação entre os padrões obtidos por ambos métodos permitiu diferenciar todas as linhagens. Agrupamentos formados com base nos dados protéicos mostraram relação com informações bioquímicas e genéticas a respeito das espécies. Os resultados mostraram que análises protéicas têm potencial para diferenciar espécies de Aeromonas, mas a baixa variação qualitativa indica que esta técnica não é eficiente para a caracterização entre linhagens dentro de espécies. Ao contrário, marcadores de RAPD permitem identificar linhagens, mas a alta variabilidade limita seu potencial como método auxiliar na identificação de espécies.

  9. 气单胞菌外膜蛋白基因工程疫苗的研究进展%Progress in Outer Membrane Protein Genetic Engineering Vaccine against Aeromonas

    Institute of Scientific and Technical Information of China (English)

    单晓枫; 曹亮; 沈锦玉; 陈龙; 康元环; 陈亨利; 钱爱东

    2014-01-01

    This article reviewed the development, immunization and disadvantages of Aeromonas outer membrane protein genetic engineering vaccine, DNA vaccine and recombinant live vector vaccine in order to provide reference for the research of Aeromonas vaccine.%就气单胞菌外膜蛋白的基因工程亚单位疫苗、DNA疫苗、重组活载体疫苗等基因工程疫苗的研究现状、免疫方式以及不足之处进行了综述,以期为气单胞菌疫苗研制提供参考。

  10. Research on Bacteriostatic and Bactericidal Effect of Chlorine Dioxide on Aeromonas%二氧化氯对气单胞菌的抑菌和杀菌效果研究

    Institute of Scientific and Technical Information of China (English)

    谭凤霞; 吴全超

    2012-01-01

    Aeromonas bacteria strains, including the standard bacteria Aeromonas hydrophila and the Aeromonas bacteria strains which isolated from the culture water or diseased fish, were used to investigate the bacteriostatic and bactericidal efficacy of chlorine dioxide to Aeromonas bacterium by double broth dilution method. The results showed that the chlorine dioxide could inhibit the growth of bacterium at the lower concentration, and killed the bacterium at the higher concentration. The minimal inhibitory concentration (MIC) of chlorine dioxide to seven Aeromonas bacterium are 12 mg/L to strians ATCC7966, Ti, T3, T4, T5; and T6, and 24 mg/L to strain T2; The minimal bactericidal concentration (MBC) of chlorine dioxide to Aeromonas are 96 mg/L to strians ATCC7966, T1, T3 and T4, and 384 mg/L to strains T2, T5 and T6. These results provided the scientific basis for reasonable application of chlorine dioxide.%以嗜水气单胞菌(Aeromonas hydrophila)标准菌株ATCC7966和分离自养殖水环境及患病鲫鱼的气单胞菌(Aeromonas)为试验菌株,通过肉汤二倍稀释法研究二氧化氯的抑菌及杀菌效果.结果表明,二氧化氯在低浓度时能抑制气单胞菌的生长增殖,高浓度时能杀灭细菌,其对ATCC7966、T1、T3、T4、T5、T6菌株的最小抑菌浓度(MIC)为12 mg/L,对T2菌株的最小抑菌浓度为24 mg/L;二氧化氯对ATCC7966、T1、T3、T4菌株的最小杀菌浓度(MBC)为96 mg/L,对T2、T5、T6菌株的最小杀菌浓度为384 mg/L.研究结果能为二氧化氯在水产养殖上的合理使用提供一定的依据.

  11. Isolation and Antimicrobial Testing of Aeromonas spp., Citrobacter spp., Cronobacter spp., Enterobacter spp., Escherichia spp., Klebsiella spp., and Trabulsiella spp. from the Gallbladder of Pigs.

    Science.gov (United States)

    Evangelopoulou, Grammato; Filioussis, Georgios; Kritas, Spyridon; Kantere, Maria; Burriel, Angeliki R

    2015-01-01

    The presence of Gram-negative bacteria species, other than Salmonella spp., in the gallbladder of pigs was examined. Isolated Gram-negative bacteria were assigned to species using the Microgen™ GnA+B-ID Systems. Of the 64 isolated strains 43 were identified as Escherichia coli, seven as Enterobacter spp., three each as Klebsiella spp., Citrobacterfreundii, Aeromonas hydrophila and Cronobacter sakazakii and one each as Escherichiafergusonii and Trabulsiella guamensis. Their antibiograms showed very high resistance to ampicillin, amoxicillin, tetracycline, chloramphenicol and sulfamethoxazole/trimethoprim. It was concluded that the pigs' gallbladder is a reservoir of potentially pathogenic Gram-negative bacteria for pork consumers.

  12. Aeromonas spp. e Plesiomonas shigelloides isoladas a partir de mexilhões (Perna perna) in natura e pré-cozidos no Rio de Janeiro, RJ

    OpenAIRE

    2004-01-01

    O ecossistema aquático é o habitat de mexilhões (Perna perna), animais filtradores que refletem a qualidade ambiental através de análise microbiológica de sua carne. No presente trabalho avaliou-se a presença de patógenos emergentes (Aeromonas hydrophila e Plesiomonas shigelloides), em mexilhões in natura e pré-cozidos coletados por pescadores da Estação Experimental de Cultivo de Mexilhões situada em Jurujuba, Niterói, Rio de Janeiro. Foram analisadas 86 amostras de mexilhões (43 in natura e...

  13. EVALUASI PEMBERIAN PROBIOTIK BACILLUS PADA MEDIA PEMELIHARAAN TERHADAP LAJU PERTUMBUHAN DAN PERUBAHAN HISTOPATOLOGI IKAN LELE DUMBO (Clarias gariepinus) YANG DIINFEKSI Aeromonas hydrophila

    OpenAIRE

    Angela Mariana Lusiastuti; Mohammad Faizal Ulkhaq; Widanarni Widanarni; Tri Heru Prihadi

    2016-01-01

    The aim of this study was to evaluate the addition of a probiotic Bacillus on culture medium through growth rate and histopathological change in African Catfish who was infected by Aeromonas hydrophila. The study consisted of five treatments such as the addition of probiotic Bacillus ND2, Bacillus P4I2, Bacillus ND2 + Bacillus P4I2 (Kom), positive control (K+) and negative control (K-) (without probiotic addition). African Catfish (13.354±2.8 g) was maintained in 15 aquariums (40 L in volume)...

  14. Effect of Shilajit enriched diet on immunity, antioxidants, and disease resistance in Macrobrachium rosenbergii (de Man) against Aeromonas hydrophila.

    Science.gov (United States)

    Musthafa, Mohamed Saiyad; Jawahar Ali, Abdul Rahman; Hyder Ali, Abdul Rahuman; Mohamed, Mohamed Jamal; War, Mehrajuddin; Naveed, Mohamed Saquib; Al-Sadoon, Mohammad K; Paray, Bilal Ahmad; Rani, Kuppusamy Umaa; Arockiaraj, Jesu; Balasundaram, Chellam; Harikrishnan, Ramasamy

    2016-10-01

    The effect of diet supplemented with Shilajit, a multi-component natural mineral substance on the antioxidant activity, immune response, and disease resistance in freshwater prawn, Macrobrachium rosenbergii (de Man) against Aeromonas hydrophila is reported. The total hemocyte count (THC) and phagocytic activity significantly increased with 2 g kg(-1) supplemented diet on first week and with other enriched diets on weeks 2 and 4. The respiratory burst (RB) activity and glutathione peroxidase (GPx) activity were significantly increased with 2 g kg(-1) supplemented diet on weeks 1 and 2 whereas 2 and 4 g kg(-1) diets on week 4. The phenoloxidase (PO) activity increased significantly with 2 g kg(-1) diet only on second week and with other enriched diets only on fourth week. The superoxide dismutase (SOD) activity increased significantly with any enriched diet during the experimental period except with 6 g kg(-1) diets on first week. However, the glutathione reductase (GR) activity was enhanced significantly only with 2 g kg(-1) enriched diets on weeks 2 and 4. The cumulative mortality of the prawn fed with 2 and 4 g kg(-1) enriched diets was 10% and 15% whereas with 6 g kg(-1) diet the mortality was 20%. The results suggest that diet enriched with Shilajit at 2 g kg(-1) or 4 g kg(-1) positively enhances the antioxidant activity, immunity, and disease resistance in M. rosenbergii against A. hydrophila.

  15. Involvement of Acylated Homoserine Lactones (AHLs) of Aeromonas sobria in Spoilage of Refrigerated Turbot (Scophthalmus maximus L.).

    Science.gov (United States)

    Li, Tingting; Cui, Fangchao; Bai, Fengling; Zhao, Guohua; Li, Jianrong

    2016-07-13

    One quorum sensing strain was isolated from spoiled turbot. The species was determined by 16S rRNA gene analysis and classical tests, named Aeromonas sobria AS7. Quorum-sensing (QS) signals (N-acyl homoserine lactones (AHLs)) were detected by report strains and their structures were further determined by GC-MS. The activity changes of AHLs on strain growth stage as well as the influence of different culture conditions on secretion activity of AHLs were studied by the punch method. The result indicated that strain AS7 could induce report strains to produce typical phenotypic response. N-butanoyl-dl-homoserine lactone (C₄-HSL), N-hexanoyl-dl-homoserine lactone (C₆-HSL), N-octanoyl-dl-homoserine lactone (C₈-HSL), N-decanoyl-dl-homoserine lactone (C10-HSL), N-dodecanoyl-dl-homoserine lactone (C12-HSL) could be detected. The activities of AHLs were density-dependent and the max secretion level was at pH 8, sucrose culture, 1% NaCl and 32 h, respectively. The production of siderophore in strain AS7 was regulated by exogenous C₈-HSL, rather than C₆-HSL. Exogenous C₄-HSL and C₈-HSL accelerated the growth rate and population density of AS7 in turbot samples under refrigerated storage. However, according to the total viable counts and total volatile basic nitrogen (TVB-N) values of the fish samples, exogenous C₆-HSL did not cause spoilage of the turbot fillets. In conclusion, our results suggested that QS was involved in the spoilage of refrigerated turbot.

  16. A tandem-repeat galectin-9 involved in immune response of yellow catfish, Pelteobagrus fulvidraco, against Aeromonas hydrophila.

    Science.gov (United States)

    Wang, Yun; Ke, Fei; Ma, Jingjing; Zhou, Shuaibang

    2016-04-01

    Galectins exclusively recognize and bind β-galactoside on cell surface by carbohydrate recognition domain (CRD). In spite of extensive study of mammalian galectin importance in immune system, little is known about that of fish. To study the immune response of yellow catfish to pathogens, a tandem-repeat galectin-9 from yellow catfish was identified and named PfGAL9. Its full-length cDNA was 1314 bp, including a 117 bp of 5' untranslated region (UTR), a 951 bp of open reading frame (ORF), and a 246 bp of 3' UTR. The ORF encoded 316 amino acids (35.12 KDa), shared the highest 78% identity with the predicted galectin-9 of Ictalurus punctatus. This protein possessed two distinct CRDs with two highly conserved sugar binding motifs. Quantitative PCR showed that PfGAL9 was lowly expressed in skin, gill, fin, muscle, heart, and intestine, highly expressed in tested immune tissues (head kidney, trunk kidney, liver, spleen, and blood) in normal body. After inactivated Aeromonas hydrophila challenge, PfGAL9 was remarkably increased in head kidney and liver in a time-dependent manner. The recombinant protein was expressed in Escherichia coli, which not only agglutinated but also bond all examined bacteria. The binding activities are consistent with the size of aggregates formed by agglutinated bacteria. The agglutination must depend on its direct interaction with bacteria. These results suggested that PfGAL9 was involved in the innate immune response against bacterial infection and clearance of pathogens in yellow catfish.

  17. High prevalence of blaCTX-M group genes in Aeromonas dhakensis isolated from aquaculture fish species in South Korea.

    Science.gov (United States)

    Yi, Seung-Won; Chung, Tae-Ho; Joh, Seong-Joon; Park, Chul; Park, Byoung-Yong; Shin, Gee-Wook

    2014-12-01

    The prevalence of resistant genes against β-lactams in 119 Aeromonas strains was determined. A large number (99.2%) of the present fish strains were resistant to one or more β- lactams including ceftiofur, amoxicillin-clavulanic acid, ampicillin, piperacillin and cefpodoxime. Among antibiotic resistance phenotypes, the simultaneous resistance to all β-lactams occurred in 25.2% (n=30) of all strains, which consisted of 18 strains of A. dhakensis, 8 strains of A. caviae, 2 strains of A. hydrophila and only one strain of A. veronii. For exploring genetic background of the antibiotic resistances, multiple PCR assays were subjected to detect β-lactamase-encoding genes, bla(TEM), bla(OXA-B) and bla(CTX-M). In the results, the bla(TEM-1) gene was harbored in all strains, whereas only 3 strains harbored bla(OXA) gene. In the case of bla(CTX-M) gene, the gene was detected in 21.0% (25 out of 119) of all strains, which countered with 80% (20 out of 25) of A. dhakensis, 8% (2 out of 25) of A. caviae and 12% (3 out of 25) of A. hydrophila. In addition, most of the bla(CTX-M) positive strains showed simultaneous resistance to all β-lactams (18 out of 30 strains). In sequence analysis for bla(CTX-M) genes detected, they were CTX-M group 1-encoding genes including bla(CTX-M-33) from 3 eel strains of A. dhakensis. Therefore, A. dhakensis obtained from cultured fish could represent a reservoir for spreading genes encoding CTX-M group 1 enzymes and hence should be carefully monitored, especially for its potential risk to public health.

  18. Transcriptome Analysis of the Innate Immunity-Related Complement System in Spleen Tissue of Ctenopharyngodon idella Infected with Aeromonas hydrophila.

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    Yunfei Dang

    Full Text Available The grass carp (Ctenopharyngodon idella is an important commercial farmed herbivorous fish species in China, but is susceptible to Aeromonas hydrophila infections. In the present study, we performed de novo RNA-Seq sequencing of spleen tissue from specimens of a disease-resistant family, which were given intra-peritoneal injections containing PBS with or without a dose of A. hydrophila. The fish were sampled from the control group at 0 h, and from the experimental group at 4, 8, 12, 24, 48 and 72 h. 122.18 million clean reads were obtained from the normalized cDNA libraries; these were assembled into 425,260 contigs and then 191,795 transcripts. Of those, 52,668 transcripts were annotated with the NCBI Nr database, and 41,347 of the annotated transcripts were assigned into 90 functional groups. 20,569 unigenes were classified into six main categories, including 38 secondary KEGG pathways. 2,992 unigenes were used in the analysis of differentially expressed genes (DEGs. 89 of the putative DEGs were related to the immune system and 41 of them were involved in the complement and coagulation cascades pathway. This study provides insights into the complement and complement-related pathways involved in innate immunity, through expression profile analysis of the genomic resources in C. idella. We conclude that complement and complement-related genes play important roles during defense against A. hydrophila infection. The immune response is activated at 4 h after the bacterial injections, indicating that the complement pathways are activated at the early stage of bacterial infection. The study has improved our understanding of the immune response mechanisms in C. idella to bacterial pathogens.

  19. Triclosan Resistance in a Bacterial Fish Pathogen, Aeromonas salmonicida subsp. salmonicida, is Mediated by an Enoyl Reductase, FabV.

    Science.gov (United States)

    Khan, Raees; Lee, Myung Hwan; Joo, Hae-Jin; Jung, Yong-Hoon; Ahmad, Shabir; Choi, Jin-Hee; Lee, Seon-Woo

    2015-04-01

    Triclosan, the widely used biocide, specifically targets enoyl-acyl carrier protein reductase (ENR) in the bacterial fatty acid synthesis system. Although the fish pathogen Aeromonas salmonicida subsp. salmonicida exhibits triclosan resistance, the nature of this resistance has not been elucidated. Here, we aimed to characterize the triclosan resistance of A. salmonicida subsp. salmonicida causing furunculosis. The fosmid library of triclosan-resistant A. salmonicida subsp. salmonicida was constructed to select a fosmid clone showing triclosan resistance. With the fosmid clone showing triclosan resistance, a subsequent secondary library search resulted in the selection of subclone pTSR-1. DNA sequence analysis of pTSR-1 revealed the presence of a chromosomal-borne fabV-encoding ENR homolog. The ENR of A. salmonicida (FabVas) exhibited significant homology with previously known FabV, including the catalytic domain YX(8)K. fabVas introduction into E. coli dramatically increased its resistance to triclosan. Heterologous expression of FabVas might functionally replace the triclosan-sensitive FabI in vivo to confer E. coli with triclosan resistance. A genome-wide search for fabVas homologs revealed the presence of an additional fabV gene (fabVas2) paralog in A. salmonicida strains and the fabVas orthologs from other gram-negative fish pathogens. Both of the potential FabV ENRs expressed similarly with or without triclosan supplement. This is the first report about the presence of two potential FabV ENRs in a single pathogenic bacterium. Our result suggests that triclosan-resistant ENRs are widely distributed in various bacteria in nature, and the wide use of this biocide can spread these triclosan-tolerant ENRs among fish pathogens and other pathogenic bacteria.

  20. Protection of Carassius auratus Gibelio against infection by Aeromonas hydrophila using specific immunoglobulins from hen egg yolk

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-liang; SHUAI Jiang-bing; FANG Wei-huan

    2006-01-01

    Specific immunoglobulin (IgY) from egg yolk against Aeromonas hydrophila was produced by immunization of White Leghorn hens with formalin-killed whole cells of A. hydrophila. ELISA test using A. hydrophila as the coating antigen revealed that the specific antibody titer started to increase in the egg yolk at the 13th day post-immunization (P/N=2.18), reached the peak at the 56th day (P/N=13.82), and remained at high level until day 133 (P/N=7.03). The antibody was purified by saturated ammonium sulphate with a recovery rate of 63.5%. The specific IgY inhibited the growth ofA. hydrophila at a concentration of 1.0mg/ml during the 18 h incubation. Pre-treatment of polyploid gibel carps Carassius auratus Gibelio with specific IgY had a protection rate of 60% (6/10) against challenge with A. hydrophila, while none of the fishes in the control groups receiving sterile phosphate buffered saline (PBS) or non-specific IgY survived the challenge. Treatment of fishes with the specific IgY 4 h after the challenge also had lower mortality (70%, 7/10), a 30% reduction against the control PBS or non-specific IgY groups (10/10).These results indicate that specific IgY antibodies could be obtained easily from hens immunized with an inactivated A. hydrophila and could provide a novel alternative approach to control of diseases in fishes caused by this organism.

  1. Novel microbial route to synthesize ZnO nanoparticles using Aeromonas hydrophila and their activity against pathogenic bacteria and fungi

    Science.gov (United States)

    Jayaseelan, C.; Rahuman, A. Abdul; Kirthi, A. Vishnu; Marimuthu, S.; Santhoshkumar, T.; Bagavan, A.; Gaurav, K.; Karthik, L.; Rao, K. V. Bhaskara

    2012-05-01

    In the present work, we describe a low-cost, unreported and simple procedure for biosynthesis of zinc oxide nanoparticles (ZnO NPs) using reproducible bacteria, Aeromonas hydrophila as eco-friendly reducing and capping agent. UV-vis spectroscopy, XRD, FTIR, AFM, NC-AFM and FESEM with EDX analyses were performed to ascertain the formation and characterization of ZnO NPs. The synthesized ZnO NPs were characterized by a peak at 374 nm in the UV-vis spectrum. XRD confirmed the crystalline nature of the nanoparticles and AFM showed the morphology of the nanoparticle to be spherical, oval with an average size of 57.72 nm. Synthesized ZnO NPs showed the XRD peaks at 31.75°, 34.37°, 47.60°, 56.52°, 66.02° and 75.16° were identified as (1 0 0), (0 0 2), (1 0 1), (1 0 2), (1 1 0), (1 1 2) and (2 02 ) reflections, respectively. Rietveld analysis to the X-ray data indicated that ZnO NPs have hexagonal unit cell at crystalline level. The size and topological structure of the ZnO NPs was measured by NC-AFM. The morphological characterization of synthesized nanoparticles was analyzed by FESEM and chemical composition by EDX. The antibacterial and antifungal activity was ended with corresponding well diffusion and minimum inhibitory concentration. The maximum zone of inhibition was observed in the ZnO NPs (25 μg/mL) against Pseudomonas aeruginosa (22 ± 1.8 mm) and Aspergillus flavus (19 ± 1.0 mm). Bacteria-mediated ZnO NPs were synthesized and proved to be a good novel antimicrobial material for the first time in this study.

  2. Structural Studies of the Lipopolysaccharide from the Fish Pathogen Aeromonas veronii Strain Bs19, Serotype O16

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    Anna Turska-Szewczuk

    2014-03-01

    Full Text Available Chemical analyses, mass spectrometry, and NMR spectroscopy were applied to study the structure of the lipopolysaccharide (LPS isolated from Aeromonas veronii strain Bs19, serotype O16. ESI-MS revealed that the most abundant LPS glycoforms have tetra-acylated or hexa-acylated lipid A species, consisting of a bisphosphorylated GlcN disaccharide with an AraN residue as a non-stoichiometric substituent, and a core oligosaccharide composed of Hep5Hex3HexN1Kdo1P1. Sugar and methylation analysis together with 1D and 2D 1H and 13C NMR spectroscopy were the main methods used, and revealed that the O-specific polysaccharide (OPS of A. veronii Bs19 was built up of tetrasaccharide repeating units with the structure: →4-α-d-Quip3NAc-(1→3-α-l-Rhap-(1→4-β-d-Galp-(1→3-α-d-GalpNAc-(1→. This composition was confirmed by mass spectrometry. The charge-deconvoluted ESI FT-ICR MS recorded for the LPS preparations identified mass peaks of SR- and R-form LPS species, that differed by Δm = 698.27 u, a value corresponding to the calculated molecular mass of one OPS repeating unit (6dHexNAc6dHexHexHexNAc-H2O. Moreover, unspecific fragmentation spectra confirmed the sequence of the sugar residues in the OPS and allowed to assume that the elucidated structure also represented the biological repeating unit.

  3. Improvement of methyl orange dye biotreatment by a novel isolated strain, Aeromonas veronii GRI, by SPB1 biosurfactant addition.

    Science.gov (United States)

    Mnif, Inès; Maktouf, Sameh; Fendri, Raouia; Kriaa, Mouna; Ellouze, Semia; Ghribi, Dhouha

    2016-01-01

    Aeromonas veronii GRI (KF964486), isolated from acclimated textile effluent after selective enrichment on azo dye, was assessed for methyl orange biodegradation potency. Results suggested the potential of this bacterium for use in effective treatment of azo-dye-contaminated wastewaters under static conditions at neutral and alkaline pH value, characteristic of typical textile effluents. The strain could tolerate higher doses of dyes as it was able to decolorize up to 1000 mg/l. When used as microbial surfactant to enhance methyl orange biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized slightly the decolorization efficiency at an optimal concentration of about 0.025%. In order to enhance the process efficiency, a Taguchi design was conducted. Phytotoxicity bioassay using sesame and radish seeds were carried out to assess the biotreatment effectiveness. The bacterium was able to effectively decolorize the azo dye when inoculated with an initial optical density of about 0.5 with 0.25% sucrose, 0.125% yeast extract, 0.01% SPB1 biosurfactant, and when conducting an agitation phase of about 24 h after static incubation. Germination potency showed an increase toward the nonoptimized conditions indicating an improvement of the biotreatment. When comparing with synthetic surfactants, a drastic decrease and an inhibition of orange methyl decolorization were observed in the presence of CTAB and SDS. The nonionic surfactant Tween 80 had a positive effect on methyl orange biodecolorization. Also, studies ensured that methyl orange removal by this strain could be due to endocellular enzymatic activities. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing effective decolorization period, biosurfactant stimulated bacterial decolorization method may provide highly efficient, inexpensive, and time-saving procedure in treatment of textile effluents.

  4. The mosaic architecture of Aeromonas salmonicida subsp. salmonicida pAsa4 plasmid and its consequences on antibiotic resistance

    Science.gov (United States)

    Tanaka, Katherine H.; Vincent, Antony T.; Trudel, Mélanie V.; Paquet, Valérie E.; Frenette, Michel

    2016-01-01

    Aeromonas salmonicida subsp. salmonicida, the causative agent of furunculosis in salmonids, is an issue especially because many isolates of this bacterium display antibiotic resistances, which limit treatments against the disease. Recent results suggested the possible existence of alternative forms of pAsa4, a large plasmid found in A. salmonicida subsp. salmonicida and bearing multiple antibiotic resistance genes. The present study reveals the existence of two newly detected pAsa4 variants, pAsa4b and pAsa4c. We present the extensive characterization of the genomic architecture, the mobile genetic elements and the antimicrobial resistance genes of these plasmids in addition to the reference pAsa4 from the strain A449. The analysis showed differences between the three architectures with consequences on the content of resistance genes. The genomic plasticity of the three pAsa4 variants could be partially explained by the action of mobile genetic elements like insertion sequences. Eight additional isolates from Canada and Europe that bore similar antibiotic resistance patterns as pAsa4-bearing strains were genotyped and specific pAsa4 variants could be attributed to phenotypic profiles. pAsa4 and pAsa4c were found in Europe, while pAsa4b was found in Canada. In accordance with their content in conjugative transfer genes, only pAsa4b and pAsa4c can be transferred by conjugation in Escherichia coli. The plasticity of pAsa4 variants related to the acquisition of antibiotic resistance indicates that these plasmids may pose a threat in terms of the dissemination of antimicrobial-resistant A. salmonicida subsp. salmonicida bacteria. PMID:27812409

  5. The mosaic architecture of Aeromonas salmonicida subsp. salmonicida pAsa4 plasmid and its consequences on antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Katherine H. Tanaka

    2016-10-01

    Full Text Available Aeromonas salmonicida subsp. salmonicida, the causative agent of furunculosis in salmonids, is an issue especially because many isolates of this bacterium display antibiotic resistances, which limit treatments against the disease. Recent results suggested the possible existence of alternative forms of pAsa4, a large plasmid found in A. salmonicida subsp. salmonicida and bearing multiple antibiotic resistance genes. The present study reveals the existence of two newly detected pAsa4 variants, pAsa4b and pAsa4c. We present the extensive characterization of the genomic architecture, the mobile genetic elements and the antimicrobial resistance genes of these plasmids in addition to the reference pAsa4 from the strain A449. The analysis showed differences between the three architectures with consequences on the content of resistance genes. The genomic plasticity of the three pAsa4 variants could be partially explained by the action of mobile genetic elements like insertion sequences. Eight additional isolates from Canada and Europe that bore similar antibiotic resistance patterns as pAsa4-bearing strains were genotyped and specific pAsa4 variants could be attributed to phenotypic profiles. pAsa4 and pAsa4c were found in Europe, while pAsa4b was found in Canada. In accordance with their content in conjugative transfer genes, only pAsa4b and pAsa4c can be transferred by conjugation in Escherichia coli. The plasticity of pAsa4 variants related to the acquisition of antibiotic resistance indicates that these plasmids may pose a threat in terms of the dissemination of antimicrobial-resistant A. salmonicida subsp. salmonicida bacteria.

  6. Potential role of specific antibodies as important vaccine induced protective mechanism against Aeromonas salmonicida in rainbow trout.

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    Kasper Rømer Villumsen

    Full Text Available Furunculosis caused by infection with Aeromonas salmonicida subsp. salmonicida has been a known threat to aquaculture for more than a century. Efficient prophylactic approaches against this disease are essential for continued growth of salmonid aquaculture. Since the introduction of successful oil-adjuvanted vaccines in the early 1990's, a number of studies have been published on the protective as well as adverse effects of these vaccines. Most studies focus on vaccination of salmon (Salmo salar. However, rainbow trout (Oncorhynchus mykiss are also very susceptible to infection and are vaccinated accordingly. In this study we have examined the protection against infection with a Danish strain of A. salmonicida in both vaccinated and non-vaccinated rainbow trout. A commercial and an experimental auto-vaccine were tested. The protective effects of the vaccines were evaluated through an A. salmonicida challenge 18 weeks post vaccination. Both vaccines resulted in a significantly increased survival in the vaccinated fish during a 28 day challenge period relative to non-vaccinated fish (P = 0.01 and P = 0.001 for the commercial and experimental vaccine, respectively. Throughout the entire experiment, the presence of specific antibodies in plasma was monitored using ELISA. A significant increase in specific antibody levels was seen in fish vaccinated with both vaccines during the 18 weeks between vaccination and challenge. Within 3 days post challenge, a significant decrease in specific antibodies occurred in vaccinated fish. A positive correlation was found between mean levels of specific antibodies pre challenge and overall survival. This correlation, along with the observed depletion of antibodies during the initial phase of infection, suggests that specific antibodies play an essential role in vaccine mediated protection against A. salmonicida in rainbow trout.

  7. Implication of lateral genetic transfer in the emergence of Aeromonas hydrophila isolates of epidemic outbreaks in channel catfish.

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    Mohammad J Hossain

    Full Text Available To investigate the molecular basis of the emergence of Aeromonas hydrophila responsible for an epidemic outbreak of motile aeromonad septicemia of catfish in the Southeastern United States, we sequenced 11 A. hydrophila isolates that includes five reference and six recent epidemic isolates. Comparative genomics revealed that recent epidemic A. hydrophila isolates are highly clonal, whereas reference isolates are greatly diverse. We identified 55 epidemic-associated genetic regions with 313 predicted genes that are present in epidemic isolates but absent from reference isolates and 35% of these regions are located within genomic islands, suggesting their acquisition through lateral gene transfer. The epidemic-associated regions encode predicted prophage elements, pathogenicity islands, metabolic islands, fitness islands and genes of unknown functions, and 34 of the genes encoded in these regions were predicted as virulence factors. We found two pilus biogenesis gene clusters encoded within predicted pathogenicity islands. A functional metabolic island that encodes a complete pathway for myo-inositol catabolism was evident by the ability of epidemic A. hydrophila isolates to use myo-inositol as a sole carbon source. Testing of A. hydrophila field isolates found a consistent correlation between myo-inositol utilization as a sole carbon source and the presence of an epidemic-specific genetic marker. All epidemic isolates and one reference isolate shared a novel O-antigen cluster. Altogether we identified four different O-antigen biosynthesis gene clusters within the 11 sequenced A. hydrophila genomes. Our study reveals new insights into the evolutionary changes that have resulted in the emergence of recent epidemic A. hydrophila strains.

  8. Biodegradation of Methyl Orange by alginate-immobilized Aeromonas sp. in a packed bed reactor: external mass transfer modeling.

    Science.gov (United States)

    Kathiravan, Mathur Nadarajan; Praveen, Siluvai Antony; Gim, Geun Ho; Han, Gui Hawn; Kim, Si Wouk

    2014-11-01

    Azo dyes are recalcitrant and xenobiotic nature makes these compounds a challenging task for continuous biodegradation up to satisfactorily levels in large-scale. In the present report, the biodegradation efficiency of alginate immobilized indigenous Aeromonas sp. MNK1 on Methyl Orange (MO) in a packed bed reactor was explored. The experimental results were used to determine the external mass transfer model. Complete MO degradation and COD removal were observed at 0.20 cm bead size and 120 ml/h flow rate at 300 mg/l of initial dye concentration. The degradation of MO decreased with increasing bead sizes and flow rates, which may be attributed to the decrease in surface of the beads and higher flux of MO, respectively. The experimental rate constants (k ps) for various beads sizes and flow rates were calculated and compared with theoretically obtained rate constants using external film diffusion models. From the experimental data, the external mass transfer effect was correlated with a model J D = K Re (-(1 - n)). The model was tested with K value (5.7) and the Colburn factor correlation model for 0.20, 0.40 and 0.60 bead sizes were J D = 5.7 Re (-0.15), J D = 5.7 Re (-0.36) and J D = 5.7 Re (-0.48), respectively. Based on the results, the Colburn factor correlation models were found to predict the experimental data accurately. The proposed model was constructive to design and direct industrial applications in packed bed reactors within acceptable limits.

  9. Protective potency of clove oil and its transcriptional down-regulation of Aeromonas sobria virulence genes in African catfish (Clarias gariepinus L.).

    Science.gov (United States)

    Abd El-Hamid, M I; Abd El-Aziz, N K; Ali, H A

    2016-08-31

    Disease episodes of fish caused by Aeromonas species are moved to the top list of limiting problems worldwide. The present study was planned to verify the in vitro antibacterial activities as well as the in vivo potential values of clove oil and ciprofloxacin against Aeromonas sobria in African catfish (Clarias gariepinus). The in vitro phenotypic virulence activities and the successful amplification of aerolysin and hemolysin genes in the precisely identified A. sobria strain were predictive for its virulence. In the in vivo assay, virulence of A. sobria strain was fully demonstrated based on constituent mRNA expression profile of tested virulence genes and typical septicemia associated with high mortalities of infected fish. Apparent lower mortality rates were correlated well with both decrescent bacterial burden and significant down-regulated transcripts of representative genes in the treated groups with clove oil, followed by ciprofloxacin as a prophylactic use for 15 days (P < 0.0001); however, the essential oil apart from ciprofloxacin significantly enhanced different hematological parameters (P < 0.05). In addition, administration of antibiotic may be considered as a pronounced stress factor in the fish even when it used in the prophylactic dose. In conclusion, medicinal plants-derived essential oils provide a virtually safer alternative to chemotherapeutics on fish, consumers and ecosystems.

  10. Prevalence and antimicrobial resistance analysis of Aeromonas in Beijing%北京地区气单胞菌的流行状况及耐药性分析

    Institute of Scientific and Technical Information of China (English)

    陈素明; 鲍春梅; 崔恩博; 郭桐生; 张鞠玲; 王欢; 曲芬

    2011-01-01

    Objective To enhance the knowledge of distribution feature and antibiotic resistance in Aeromonas species isolated from infected patients on pastients in order to offer the scientific gist for clinical analysing pathogenetic condition and adopting antibiotics treatment. Methods Bacteria were isolated and identified from samples in infected patients with clinical manifestation. Furthermore the sensitivity of Aeromonas to antimicrobial agents was measured by K-B according to CLSI and the distribution feature and antibiotic resistance of various Aeromonas species were analyzed. Results Aeromonas infected happened in enteron frequently, following up blood and ascites. Among 280 cases of Aeromonas, 87.86% occurred in summer and autumn. Aeromonas sobria was the most common species (40%) and Aeromonas hydrophila was secondary (28.22%). Others were Aeromonas caviae (20.36%), Aeromonas veronni (5.71%) and few species. The resistant rate to antimicrobiai of Aeromonas species isolated from enteron was higher in ampicillin (87.9%), trimethoprim-sulfamethoxazole (61.3%), ceftriaxone (29.4%),cefmetazole (28.6%). The resistant rate to ceftriaxone, cefmetazole, ciprofloxacin of Aeromonas hydrophila and Aeromonas caviae was overtopping that of Aeromonas sobria. The resistance rate to ceftriaxone, levofloxacin, and trimethoprim-sulfamethoxazole of Aeromonas species isolated enteron was higher than that of blood and ascites.Conclusion Aeromonas sobria and Aeromonas hydrophila are majority species and occur in summer and autumn frequently in Beijing. The different resistant rate to some antimicrobial exist in various species and infected site so patients should be treated differently according to the susceptibility test.%目的 了解临床分离气单胞菌感染的分布特点及耐药性状况,为临床评估病情及合理选择抗菌药物提供客观依据.方法 有感染临床表现患者的标本进行培养、分离和鉴定,同时用纸片扩散法测定

  11. Molecular identification of 4 clinical Aeromonas isolates by gyrB and rpoB gene sequencing%4株气单胞菌临床分离株基于gyrB和rpoB基因序列的分子鉴定

    Institute of Scientific and Technical Information of China (English)

    韦小瑜; 游旅; 田克诚; 朱琳; 张仁俊; 吉光辉; 唐光鹏; 王定明

    2016-01-01

    目的:对4株气单胞菌临床分离株进行菌种的分子鉴定,为气单胞菌的种型鉴定提供病原学依据。方法对4株系统生化鉴定为气单胞菌的菌株,提取核酸作为模板,分别使用gyrB、rpoB基因进行扩增及产物测序,将所得序列在GenBank中进行同源性搜索,与GenBank中已经公布的同源性较高的气单胞菌序列比较构建系统发育树并进行分析。结果4株气单胞菌gyrB基因序列经同源性搜索,与多株嗜水气单胞菌和豚鼠气单胞菌同源性为99%,rpoB基因序列则与多株豚鼠气胞菌同源性为99%~100%,对gyrB基因和rpoB基因序列分别进行系统发育树分析显示,4株气单胞菌菌株在gyrB基因系统发育树中与多株嗜水气单胞菌和豚鼠气单胞菌聚为一簇,而在rpoB基因系统发育树中与多株豚鼠气单胞菌聚在同一分枝内。结论4株气单胞菌经rpoB基因测序分析明确鉴定为豚鼠气单胞菌,gyrB基因测序分析不能有效鉴定其种型。%Objective To identify the gene species of 4 clinical Aeromonas isolates and to provide the etiologic basis for the identification of Aeromonas species. Methods The isolates were identified as Aeromonas by conventional biochemical methods. The DNA of Aeromonas isolates was extracted as the template of PCR. The gyrB and rpoB gene were amplified and sequenced. Two sequence homology searches were conducted on GenBank and selected closely homology strains. Two molecular phylogenetic trees were constructed for analyze. Results The sequence homology of gyrB gene was 99% among Aeromonas isolates、 Aeromonas hydrophila and Aeromonas caviae strains,99%~100%(rpoB) among Aeromonas isolates and Aeromonas caviae strains. The phylogenetic tree of gyrB gene showed that 4 Aeromonas isolates、Aeromonas caviae strains and Aeromonas hydrophila strains were clustered in the same group. While 4 Aeromonas isolates fell into the same branch with Aeromonas caviae strains

  12. Detection of Pathogenic Aeromonas hydrophila by Dot-ELISA%Dot-ELISA法检测致病性嗜水气单胞菌

    Institute of Scientific and Technical Information of China (English)

    任燕; 潘子豪; 陆承平; 姚火春; 吴淑勤

    2011-01-01

    On the basis of diagnosis kit for pathogenic Aeromonas, ECPase54 produced by Aeromonas hydrophila (Ah) was detected by Dot-ELISA. On the other hand, the 16S rRNA and aerolysin of pathogenic Aeromonas hydrophila (Pah) were detected with PCR. Furthermore the skimmed milk plate tests were processed. 72 Aeromonas isolates were detected with the 4 different methods. The positive rate of 72 isolates was 90. 3%(65/72)with Dot-ELISA method , 75% (54/72)with skimmed milk plate method, 94. 4% (68/72) with aer gene PCR method, 81. 9% (59/72) with 16S rRNA PCR method. Compared Dot-ELISA and the other three methods (skimmed milk plate, aer gene PCR and 16S rRNA PCR), the coincidence rate was 79. 2%(57/ 72), 91. 6%(66/72), 81. 9%(59/72), respectively. The 72 isolates were repeatedly detected with Dot-ELISA in 2, 4, 6, 12 and 18 months after preparing of the anti-ECPase54 rabbit serum, and the similarly results were got. In conclusion, this Dot-ELISA method is sensitive, specific and practical. It can be used as a method for rapid diagnosis of Pah in clinic.%在鱼类致病性气单胞菌诊断试剂盒的基础上,用斑点酶联免疫吸附试验(Dot-ELISA)检测致病性嗜水气单胞菌(Aeromonas hydrophila,Ah)胞外蛋白酶ECPase54,同时用脱脂奶平板、PCR特异性扩增气溶素基因aer和16S rRNA基因检测72株气单胞菌分离株.结果显示致病性嗜水气单胞菌检测阳性率分别如下:Dot-ELISA法90.3%(65/72)、脱脂奶平板法75%(54/72)、aer基因PCR法94.4%(68/72)、16S rRNA PCR法81.9%(59/72),Dot-ELISA与其他3种方法的符合率分别为79.2%(57/72)、91.6%(66/72)、81.9%(59/72).在ECPase54兔抗血清制备后的2、4、6、12、18个月,用Dot-ELISA检测72株分离株,检测结果重复性好.结果表明Dot-ELISA法敏感、特异、实用,可用于鱼类致病性Ah的临床诊断.

  13. Occurrence and significance of atypical Aeromonas salmonicida in non-salmonid and salmonid fish species: a review.

    Science.gov (United States)

    Wiklund, T; Dalsgaard, I

    1998-02-26

    Bacterial strains of Aeromonas salmonicida included in the recognized subsp. acromogenes, subsp. masoucida, and subsp. smithia in addition to the large number of strains not included in any of the described subspecies are referred to as atypical A. salmonicida. The atypical strains form a very heterogeneous group with respect to biochemical characteristics, growth conditions, and production of extracellular proteasess. Consequently, the present taxonomy of the species A. salmonicida is rather ambiguous. Atypical A. salmonicida has been isolated from a wide range of cultivated and wild fish species, non-salmonids as well as salmonids, inhabiting fresh water, brackish water and marine environments in northern and central Europe, South Africa, North America, Japan and Australia. In non-salmonid fish species, infections with atypical strains often manifest themselves as superficial skin ulcerations. The best known diseases associated with atypical A. salmonicida are carp Cyprinus carpio erythrodermatitis, goldfish Carassius auratus ulcer disease, and ulcer disease of flounder Platichthys flesus, but atypical strains are apparently involved in more disease outbreaks than previously suspected. Macroscopical and microscopical studies of ulcerated fish indicate internal organs are infrequently invaded by atypical A. salmonicida. This view is supported by the fact that atypical strains are irregularly isolated from visceral organs of ulcerated fish. High mortality caused by atypical A. salmonicida has been observed in populations of wild non-salmonids and farmed salmonids, although the association between the mortality in the wild fish stocks and atypical A. salmonicida has not always been properly assessed. In injection experiments the pathogenicity of the atypical strains examined showed large variation. An extacellular A-layer has been detected in different atypical strains, but virulence mechanisms different from those described for (typical) A. salmonicida subsp

  14. Aeromonas hydrophila OmpW PLGA Nanoparticle Oral Vaccine Shows a Dose-Dependent Protective Immunity in Rohu (Labeo rohita

    Directory of Open Access Journals (Sweden)

    Saurabh Dubey

    2016-06-01

    Full Text Available Aeromonas hydrophila is a Gram-negative bacterium that causes high mortality in different fish species and at different growth stages. Although vaccination has significantly contributed to the decline of disease outbreaks in aquaculture, the use of oral vaccines has lagged behind the injectable vaccines due to lack of proven efficacy, that being from primary immunization or by use of boost protocols. In this study, the outer membrane protein W (OmpW of A. hydrophila was cloned, purified, and encapsulated in poly d,l-lactide-co-glycolic acid (PLGA nanoparticles (NPs for oral vaccination of rohu (Labeo rohita Hamilton. The physical properties of PLGA NPs encapsulating the recombinant OmpW (rOmpW was characterized as having a diameter of 370–375 nm, encapsulation efficiency of 53% and −19.3 mV zeta potential. In vitro release of rOmpW was estimated at 34% within 48 h of incubation in phosphate-buffered saline. To evaluate the efficacy of the NP-rOmpW oral vaccine, two antigen doses were orally administered in rohu with a high antigen (HiAg dose that had twice the amount of antigens compared to the low antigen (LoAg dose. Antibody levels obtained after vaccination showed an antigen dose dependency in which fish from the HiAg group had higher antibody levels than those from the LoAg group. The antibody levels corresponded with post challenge survival proportions (PCSPs and relative percent survival (RPS in which the HiAg group had a higher PCSP and RPS than the LoAg group. Likewise, the ability to inhibit A. hydrophila growth on trypticase soy agar (TSA by sera obtained from the HiAg group was higher than that from the LoAg group. Overall, data presented here shows that OmpW orally administered using PLGA NPs is protective against A. hydrophila infection with the level of protective immunity induced by oral vaccination being antigen dose-dependent. Future studies should seek to optimize the antigen dose and duration of oral immunization in rohu

  15. Aeromonas hydrophila OmpW PLGA Nanoparticle Oral Vaccine Shows a Dose-Dependent Protective Immunity in Rohu (Labeo rohita).

    Science.gov (United States)

    Dubey, Saurabh; Avadhani, Kiran; Mutalik, Srinivas; Sivadasan, Sangeetha Madambithara; Maiti, Biswajit; Paul, Joydeb; Girisha, Shivani Kallappa; Venugopal, Moleyur Nagarajappa; Mutoloki, Stephen; Evensen, Øystein; Karunasagar, Indrani; Munang'andu, Hetron Mweemba

    2016-06-01

    Aeromonas hydrophila is a Gram-negative bacterium that causes high mortality in different fish species and at different growth stages. Although vaccination has significantly contributed to the decline of disease outbreaks in aquaculture, the use of oral vaccines has lagged behind the injectable vaccines due to lack of proven efficacy, that being from primary immunization or by use of boost protocols. In this study, the outer membrane protein W (OmpW) of A. hydrophila was cloned, purified, and encapsulated in poly d,l-lactide-co-glycolic acid (PLGA) nanoparticles (NPs) for oral vaccination of rohu (Labeo rohita Hamilton). The physical properties of PLGA NPs encapsulating the recombinant OmpW (rOmpW) was characterized as having a diameter of 370-375 nm, encapsulation efficiency of 53% and -19.3 mV zeta potential. In vitro release of rOmpW was estimated at 34% within 48 h of incubation in phosphate-buffered saline. To evaluate the efficacy of the NP-rOmpW oral vaccine, two antigen doses were orally administered in rohu with a high antigen (HiAg) dose that had twice the amount of antigens compared to the low antigen (LoAg) dose. Antibody levels obtained after vaccination showed an antigen dose dependency in which fish from the HiAg group had higher antibody levels than those from the LoAg group. The antibody levels corresponded with post challenge survival proportions (PCSPs) and relative percent survival (RPS) in which the HiAg group had a higher PCSP and RPS than the LoAg group. Likewise, the ability to inhibit A. hydrophila growth on trypticase soy agar (TSA) by sera obtained from the HiAg group was higher than that from the LoAg group. Overall, data presented here shows that OmpW orally administered using PLGA NPs is protective against A. hydrophila infection with the level of protective immunity induced by oral vaccination being antigen dose-dependent. Future studies should seek to optimize the antigen dose and duration of oral immunization in rohu in order to

  16. LD5o of the bacteria Aeromonas hydrophila to matrinxã, Brycon amazonicus DL5o da bactéria Aeromonas hydrophila para o matrinxã, Brycon amazonicus

    Directory of Open Access Journals (Sweden)

    Sarah Ragonha de Oliveira

    2011-01-01

    Full Text Available In order to determine the lethal dose (96-h LD50 of the bacteria Aeromonas hydrophila to matrinxã, Brycon amazonicus, to be applied in challenge tests, 90 fish (63.23 ± 6.39 g were divided into five treatments, with different bacterial solutions: T1 - Control (0.9% NaCl saline solution; T2 (4 x 10(11 cells/ mL; T3 (5 x 10(11 cells/ mL; T4 (1.36 x 10(12 cells/ mL and T5 (3.06 x 10(12 cells/ mL. Fish were previously anesthetized with benzocaine (60 mg L-1, inoculated in the peritoneal cavity with the bacterial suspensions and then distributed into fifteen 80-L test chambers, where the water variables were monitored and fish mortality was observed. The experiment was randomly designed in three replicates and the 96-h LD50 was estimated according to the trimmed Spearman-Karber method. Water quality variables remained within adequate ranges for fish health and performance. Fish mortality rate increased with the bacterial concentrations of A. hydrophila (T1 = 0%; T2 = 16.66%; T3 = 44.44%; T4 = 72.22% and T5 = 100%, and the first mortalities were observed after 57 h, although the signs of the bacterial infection were already observed 24 h after the inoculation. The results indicate that the 96-h LD50 value of A. hydrophila to matrinxã is 6.66 x 10(11 cells/ mL.Para determinar a dose letal (DL50 96-h da bactéria Aeromonas hydrophila para o matrinxã, Brycon amazonicus, com aplicabilidade para testes de desafio, foram utilizados 90 peixes (63,23 ± 6,39 g, divididos em cinco tratamentos, com diferentes soluções bacterianas: T1 - Controle (solução salina 0,9% NaCl; T2 (4 x 10(11 células/ mL; T3 (5 x 10(11 células/ mL-1; T4 (1,36 x 10(12 células/mL-1 e T5 (3,06 x 10(12 células/ mL-1. Os peixes foram previamente anestesiados com benzocaína (60 mg L-1, inoculados na cavidade peritoneal com as suspensões bacterianas e distribuídos em 15 aquários de vidro de 80 L de capacidade, com aeração constante. O experimento teve duração de 96 h, no

  17. 猪肉解冻过程中损伤型气单胞菌检测方法的优化%Optimization of Detecting Injured Aeromonas spp. During Pork Thawing

    Institute of Scientific and Technical Information of China (English)

    董庆利; 梁娜

    2012-01-01

    为优化解冻猪肉中损伤型气单胞菌的检测方法,取-18℃冷冻48 h的猪肉解冻后分别应用含0.6%酵母浸膏的胰酪胨大豆琼脂(TSAYE)、营养琼脂(NA)和气单胞菌选择性琼脂(ASA)比较损伤性气单胞菌修复效果,进而对优选的培养基分别添加2%和4%的NaCl,探讨气单胞菌的耐盐度。通过向气单胞菌的选择性培养基中分别添加1.0%、1.5%、2.0%、2.5%和3.0%的NaCl,经差异显著性分析得出合适的气单胞菌损伤培养基,最后以损伤培养基总菌数与选择性培养基之比作为修复率来比较磷酸缓冲液(PBS)、缓冲蛋白胨水(BP)和营养肉汤(NB)三种不同修复介质的差异。结果表明,TSAYE优于NA和ASA用于损伤性气单胞菌的修复,TSAYE+1.5%NaCl为合适的损伤培养基,损伤型气单胞菌的数量可以添加1.5%NaCl前后的菌落数之差来计数。同时,25℃下TSAYE+NB修复介质为损伤型气单胞菌的适宜修复条件,修复时间为1 h。%In order to optimize the method for detection of injured Aeromonas spp.,thawed pork inoculated with Aeromonas spp.after frozen for 48 h under-18℃ was detected using Tryptic Soy Agar with 0.6% Yeast Extract(TSAYE),Nutrient Agar(NA) and Aeromonas Selective Agar(ASA),respectively.Then the selected medium was supplemented with 2% and 4% NaCl respectively for the study of salt-tolerance of Aeromonas spp.Furthermore,the medium was supplemented with 1.0%,1.5%,2.0%,2.5% and 3.0% NaCl,respectively,for selecting the proper injured Aeromonas spp.culture based on the analysis of variance.Moreover,the optimized comparison of repair substrate was conducted on the ratio of injuring and selecting medium counting,which based on the Phosphate Buffer System(PBS),Buffer Peptone water(BP) and Nutrient Broth(NB),respectively.Results showed that TSAYE was more appropriate than NA and ASA for the repair medium of Aeromonas spp.,and TSAYE with 1.5% NaCl could be used for counting injured

  18. CARACTERIZACIÓN Y EVALUACIÓN in vivo E in vitro DEL LIPOPOLISACÁRIDO DE Aeromonas hydrophila In Vitro/In Vivo Characterization And Evaluation Of Aeromonas hydrophila Lipopolysacharides (LPS

    Directory of Open Access Journals (Sweden)

    AP JIMÉNEZ

    Full Text Available A partir de una cepa de A. hydrophila aislada de un brote de enfermedad septicémica en Tilapia nilótica (Piaractus brachypomusoreochromis niloticus, se obtuvieron extractos de lipopolisacárido (LPS crudo (29,5 mg/ml y semipurificado (106,5 mg/ml mediante la técnica fenol-agua caliente descrita por Westphal, Jann (1965. La presencia de proteína fue del 2,3% para el extracto crudo y de 0,1% para el semipurificado; la concentración de polisacáridos osciló entre el 15 y 26%. En electroforesis (SDS-PAGE se observaron bandas de 14 Kd correspondientes al oligosacárido central y al lípido A del LPS. Tres ratones de 25-35 g fueron inoculados intraperitonealmente con 25 mg/Kg de LPS cru-do, a partir de la primera hora todos los animales mostraron erizamiento, taquipnea e inapetencia; microscópicamente se detectó congestión hepática y pulmonar, hemorragias pulmonares y renales, marginación leucocitaria en hígado y pulmón con predominio de polimorfo-nucleares neutrófilos (PMN en todos los animales, mostrando un mayor efecto que el control inoculado con LPS de E. coli (Sigma® a la misma concentración. In vitro el LPS crudo a concentración de 10, 20 y 30 µg/ml indujo proliferación de células mono-nucleares murinas (2 x 10 5 en 200 µl de medio DMEM por incorporación de timidina tritiada; tanto el LPS control (E. coli, como el LPS crudo de A. hydrophila mostraron cuentas por minuto (CPM ascendentes de manera dosis dependiente, el LPS de A. hydrophila desencadeno una proliferación muy similar a la inducida por el control.Aeromonas hydrophila isolated from a septicemic disease outbreak in tilapia (Piaractus brachypomusoreochromis niloticus was used to prepare crude (29.5 mg/ml and semipurified (106.5 mg/ml lipopolysacharide extracts (LPS based on the phenol-hot water protocol (Westphal and Jann, 1965. Protein contents were 2.3% and 0.1% for the crude and the semipurified extracts, respectively, while the polysacharides ranged from 15 to

  19. Pharmacodynamic effect of enrofloxacin against Aeromonas hydrophila in vitro pharmacokinetic model%体外药动模型中恩诺沙星对嗜水气单胞菌的药动及药效研究

    Institute of Scientific and Technical Information of China (English)

    陈俭清; 卢彤岩

    2009-01-01

    为降低嗜水气单胞菌耐药菌株的产生速度,延长恩诺沙星在水产动物上的应用年限,通过建立体外模型的方法,研究恩诺沙星对嗜水气单胞菌的药动-药效(PK-PD)参数.在消除半衰期为100 h的模型内,2 MIC(最小抑菌浓度)的恩诺沙星对嗜水气单胞菌能够抑制6 h,6 h后细菌出现再生长;4、8和16 MIC对嗜水气单胞菌能够起到持续的抑制作用.在消除半衰期为168 h的模型内,2 MIC的恩诺沙星对嗜水气单胞菌能够抑制6 h,6 h后细菌出现再生长;4、8和16 MIC对嗜水气单胞菌能够起到持续的抑制作用.结果表明,当AUC_(0→24)/MIC>75.24±13.24,C_(max)/MIC>4.10±0.12时,恩诺沙星对嗜水气单胞菌能够起到持续的抑制作用.%The purposes of this research is to decrease the occurrence speed of resistant Aeromonas hydrophila and prolong the time limit of enrofloxacin application on aquatic creature. By using in vitro pharmacokinetic model, PK-PD parameter of Aeromonas hydrophila against enrofloxacin was studied. In the in vitro model with elimination half-life of 100 h, Aeromonas hydrophila was inhibited for 6 h by 2 MIC enrofloxacin and was continuously inhibited in the entire experiment period of 24 h by 4, 8 and 16 MIC enrofloxacin. In the in vitro model with elimination half-life of 168 h, the inhibitation effect of 2 MIC enrofloxacin on Aeromonas hydrophila lasted for 6 h and the bacteria regrew after that. 4, 8 and 16 MIC enrofloxacin showed continously inhabitative action on Aeromonas hydrophila. It concluded that con-tinous inhabitation of Aeromonas hydrophila by enrofloxacin could be achieved at the condition of AUC_(0→24)/ MIC>75.24±13.24, C_(max)/MIC>4.10±0.12.

  20. MGB探针实时定量PCR检测致病性嗜水气单胞菌%Application of Real-time PCR for Detection of Aeromonas hydrophila by Using MGB Fluorescence Probe

    Institute of Scientific and Technical Information of China (English)

    高建忠; 魏雪; 童琰; 黄玉邦

    2009-01-01

    [Objective] A real-time PCR, based on TaqMan hybridization probes technology, were developed and applied to detect pathogenic Aeromonas hydrophila.One pairs of primer and one probes were designed for detection aerolysin genes.The aerolysin probe was 5′end labeled with FAM and 3′end labeled with TaqMan-MGB.The detection limits of the sensitivity assays were 1.25×100 CFU/μl;the qualitative consensus PCR assay indicated all Aeromonas hydrophila were found positive and did not detect DNA from non-Aeromonas hydrophila isolates.In the duplicated experiment, coefficients of variation intra-assay and inter-assay over the dynamic range of the MGB probe assays were lower than 3% and 5%, respectively.These results showed that this real-time PCR can detect the Aeromonas hydrophila from samples rapidly.In conclusion, this real-time PCR-based method is rapid, sensitive and specific for the detection of pathogenic Aeromonas hydrophila , and it is a practical method for pathogenic Aeromonas hydrophila detection.%以嗜水气单胞菌气溶素(aerolysin)基因为待检靶基因,设计一对引物和一条MGB(Minor Groove Binder)探针,Aero 基因探针5′端用FAM基团标记,3′端用TaqMan-MGB标记.建立并优化了检测嗜水气单胞菌荧光定量PCR方法,可检测的最低细菌数为1.25×100 CFU/μl;试验中嗜水气单胞菌检测结果均为阳性,而非嗜水气单胞菌检测结果均为阴性;重复性试验中,批间差异小于5%,批内差异小于3%.试验结果显示,荧光定量PCR方法可对致病性嗜水气单胞菌株进行快速鉴定.该方法的建立为致病性嗜水气单胞菌的检测提供了一种简便、快速的途径,是一种比较实用的致病性嗜水气单胞菌的检测方法.

  1. Enhanced reduction of waste activated sludge at a low temperature by locally isolated strains Pseudomonas sp. VNT and Aeromonas sp. VNT.

    Science.gov (United States)

    Mohd Yasin, Nazlina Haiza; Sanchez-Torres, Viviana; Maeda, Toshinari

    2014-12-01

    Appropriate control of waste activated sludge (WAS) is required to solve the annual increment of WAS volume. The low bacterial activity at low temperatures poses a difficulty in reducing or utilizing WAS in cold weather regions and/or during the winter season. This study reveals a practical method to enhance sludge reduction at a low temperature using isolated strains of Pseudomonas and Aeromonas species. The effect of inoculating each strain into WAS was examined at different temperatures (4°C, 10°C, 12°C, 15°C, 20°C, and 30°C) and under an aerobic condition. Sludge reduction showed 2- to 8-fold improvement at the temperature range from 4°C to 15°C. Both strains are psychrophilic and can produce protease and lipase for sludge degradation even at low temperatures. Thus, biological WAS treatment at a psychrophilic temperature can be enhanced by inoculating these promising strains.

  2. Influence of carvacrol and 1,8-cineole on cell viability, membrane integrity, and morphology of Aeromonas hydrophila cultivated in a vegetable-based broth.

    Science.gov (United States)

    de Sousa, Jossana Pereira; de Oliveira, Kataryne Árabe Rimá; de Figueiredo, Regina Celia Bressan Queiroz; de Souza, Evandro Leite

    2015-02-01

    This study investigated the effects of carvacrol (CAR) and 1,8-cineole (CIN) alone (at the MIC) or in combination at subinhibitory amounts (both at 1/8 MIC) on the cell viability, membrane permeability, and morphology of Aeromonas hydrophila INCQS 7966 (A. hydrophila) cultivated in a vegetable-based broth. CAR and CIN alone or in combination severely affected the viability of the bacteria and caused dramatic changes in the cell membrane permeability, leading to cell death, as observed by confocal laser microscopy. Scanning and transmission electron microscopy images of bacterial cells exposed to CAR or CIN or the mixture of both compounds revealed severe changes in cell wall structure, rupture of the plasma membrane, shrinking of cells, condensation of cytoplasmic content, leakage of intracellular material, and cell collapse. These findings suggest that CAR and CIN alone or in combination at subinhibitory amounts could be applied to inhibit the growth of A. hydrophila in foods, particularly as sanitizing agents in vegetables.

  3. Detection of Aeromonas hydrophila DNA oligonucleotide sequence using a biosensor design based on Ceria nanoparticles decorated reduced graphene oxide and Fast Fourier transform square wave voltammetry

    Energy Technology Data Exchange (ETDEWEB)

    Jafari, Safiye [Center of Excellence in Electrochemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Faridbod, Farnoush, E-mail: faridbodf@khayam.ut.ac.ir [Center of Excellence in Electrochemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Biosensor Research Center, Endocrinology & Metabolism Molecular and Cellular Research Institute, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Norouzi, Parviz [Center of Excellence in Electrochemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Biosensor Research Center, Endocrinology & Metabolism Molecular and Cellular Research Institute, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Dezfuli, Amin Shiralizadeh [Center of Excellence in Electrochemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Ajloo, Davood [School of Chemistry, Damghan University, Damghan (Iran, Islamic Republic of); Mohammadipanah, Fatemeh [Department of Microbial Biotechnology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, 14155-6455 Tehran (Iran, Islamic Republic of); Ganjali, Mohammad Reza [Center of Excellence in Electrochemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Biosensor Research Center, Endocrinology & Metabolism Molecular and Cellular Research Institute, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2015-10-01

    A new strategy was introduced for ssDNA immobilization on a modified glassy carbon electrode. The electrode surface was modified using polyaniline and chemically reduced graphene oxide decorated cerium oxide nanoparticles (CeO{sub 2}NPs-RGO). A single-stranded DNA (ssDNA) probe was immobilized on the modified electrode surface. Fast Fourier transform square wave voltammetry (FFT-SWV) was applied as detection technique and [Ru(bpy){sub 3}]{sup 2+/3+} redox signal was used as electrochemical marker. The hybridization of ssDNA with its complementary target caused a dramatic decrease in [Ru(bpy){sub 3}]{sup 2+/3+} FFT-SW signal. The proposed electrochemical biosensor was able to detect Aeromonas hydrophila DNA oligonucleotide sequence encoding aerolysin protein. Under optimal conditions, the biosensor showed excellent selectivity toward complementary sequence in comparison with noncomplementary and two-base mismatch sequences. The dynamic linear range of this electrochemical DNA biosensor for detecting 20-mer oligonucleotide sequence of A. hydrophila was from 1 × 10{sup −15} to 1 × 10{sup −8} mol L{sup −1}. The proposed biosensor was successfully applied for the detection of DNA extracted from A. hydrophila in fish pond water up to 0.01 μg mL{sup −1} with RSD of 5%. Besides, molecular docking was applied to consider the [Ru(bpy){sub 3}]{sup 2+/3+} interaction with ssDNA before and after hybridization. - Highlights: • New DNA biosensor is designed for sub-femtomolar detection of Aeromonas hydrophila DNA sequence. • Reduced graphene oxide decorated Ceria nanoparticles was used as a new immobilization platform. • Biosensor was successfully used to detect A. hydrophila DNA sequence in fish pond water.

  4. Effect of garlic peel on growth, hematological parameters and disease resistance againstAeromonas hydrophila in African catfishClarias gariepinus(Bloch) fingerlings

    Institute of Scientific and Technical Information of China (English)

    Karthik Thanikachalam; Marimuthu Kasi; Xavier Rathinam

    2010-01-01

    Objective:To evaluate the efficacy of dietary doses of garlic (Allium sativum L.) peel on the hematological and disease resistance of African catfish [Clarias gariepinus(C. gariepinus) ] fingerlings against the infections caused by opportunistic bacterial pathogenAeromonas hydrophila.Methods:Powdered garlic peel was incorporated into the diets at (0%, 0.5%, 1.0% and1.5%) and fed to catfish fingerlings for20 days. After the feeding trial, biochemical (serum total protein, albumin and globulin), hematological parameters (white blood cells and red blood cells) of the fish were examined. Fish were challenged withAeromona hydrophila (A. hydrophila) after20days of post feeding and percentage mortalities were recorded up to10 days after post challenge.Results: Enhanced serum protein, albumin and globulin in fish fed with all the dosages of garlic peel when compared to control group. Significantly highest red blood cell and white blood cell counts were recorded in garlic peel incorporated diet fed groups compared to control group. The results also demonstrate that low survival rate (55.5±11.0)% in control groups and significantly higher survival rates were recorded in all the garlic peel fed groups after challenging withA. hydrophila. However no significant impact was noticed with regard to body weight gain, specific growth rate and food conversion ratio of fish fed with different levels of garlic peel inclusion and control group.Conclusions:These results indicate that garlic peel enhances the hematological parameters even at a low level(0.5%) incorporation and makesC. gariepinus highly immunopotent and more resistant to infection byA. hydrophila.

  5. The effect of organic osmoprotectors on Aeromonas trota and A. hydrophila grown under high sodium chloride concentrations Efeito de osmoprotetores orgânicos sobre Aeromonas trota e A. hydrophila cultivada em concentrações de cloreto de sódio

    Directory of Open Access Journals (Sweden)

    Ana Paula L. Delamare

    2003-11-01

    Full Text Available The effect of organic solutes on the growth of Aeromonas trota and A. hydrophila was evaluated. Proline and glutamic acid were not effective as osmoprotectors, but betaine exerts osmoprotection allowing the growth of both strains in inhibitory concentrations of NaCl. Growth kinetics suggests that the halotolerance difference between the strains is associated with the synthesis of osmolytes rather than betaine uptake.O efeito de solutos orgânicos no crescimento de Aeromonas trota e A. hydrophila foi avaliado. A prolina e o ácido glutâmico não apresentaram efeito osmoprotetor, mas a betaina exerceu osmoproteção permitindo o crescimento de ambas bactérias em concentrações inibitórias de NaCl. A cinética do crescimento sugere que a diferença em halotolerância entre as linhagens está associada à síntese de osmolitos, mais do que à capacidade de acúmulo de betaina.

  6. Caracterização microbiológica e clínica de surtos de "red leg" em Minas Gerais e avaliação do efeito bactericida in vitro do Vantocil IB® para Aeromonas hydrophila Microbiological and clinical characterization of "red leg" outbreaks in Minas Gerais, Brazil, and evaluation of in vitro bacterial effects of Vantocil IB® for Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Anna Christina de Almeida

    2000-08-01

    Full Text Available Com o objetivo da caracterização da ocorrência de "red leg" em Minas Gerais, avaliaram-se rãs jovens e adultas que apresentavam úlceras nas patas e dedos, derrame hemorrágico na pele da região ventral, incoordenação motora, altas taxas de mortalidade em adultos e abscessos hepáticos à necropsia. No cultivo de fragmentos de pele lesada e abscessos, foi isolado e identificado Aeromonas hydrophila. O efeito bactericida do VANTOCIL IB® foi superior ao permanganato de potássio, determinado pela concentração inibitória mínima para colónias isoladas.With the objective of characterizating lhe ocurrence of "red leg" in Minas Gerais, Brazill, young and adult frogs which presented in theirpads and limbs hemorragie in the skin of the ventral region, incordination, high death rate in adults and hepatic abscess at necropsy, have been evaluated. In fragment culture ofdamage skin and abscess, Aeromonas. hydrophila hás been isolated and identified. The bactericidal effect of VANTOCIL IB® was higher than that of potassium permanganate, as determinated by the minimal inhibitory concentration for isolated colonies.

  7. Identificação e resistência a antimicrobianos de espécies de Aeromonas móveis isoladas de peixes e ambientes aquáticos Identification and antimicrobial resistance of motile Aeromonas isolated from fish and aquatic environment

    Directory of Open Access Journals (Sweden)

    Daniela Hirsch

    2006-12-01

    Full Text Available Com o objetivo de se verificar a diversidade de espécies de Aeromonas móveis e seu perfil de susceptibilidade a antimicrobianos em pisciculturas comerciais, foram selecionadas oito tilapiculturas localizadas na região do Alto Rio Grande, Minas Gerais. De cada propriedade foram coletadas três amostras de peixes em estádio de pré-abate (vivos e saudáveis, uma amostra de água do tanque e uma amostra da água de abastecimento do sistema. De cada peixe foram coletadas amostras de lavado superficial e do parênquima renal. Diluições seriadas adequadas de cada amostra foram plaqueadas em TSA-ampicilina (10 mg/l e as amostras de rim em Ágar Sangue de cavalo a 5%. A partir de colônias isoladas positivas para o teste da oxidase foram realizados testes para identificação do gênero (testes presuntivos e das espécies de Aeromonas (testes bioquímicos. O perfil de antibiograma foi obtido pelo teste de difusão de discos de antibióticos em Ágar Mueller Hinton. Foram obtidos 75 isolados diferenciados em nove espécies de Aeromonas: A. jandaei, A. hydrophila, A. trota, A. caviae, A. sobria, A. eucrenophila, A. veronii bt veronii, A. schubertii, A. media, além de amostras classificadas como Aeromonas atípicas. Do total isolado, oito amostras foram provenientes da superfície corpórea de peixes, 14 da água de abastecimento e 53 da água do tanque. Não houve isolamento a partir dos espécimes de parênquima renal. Em relação ao perfil de resistência, 93% dos isolados foram resistentes à eritromicina, 36% à tetraciclina, 13% ao ác. nalidíxico, 9% à gentamicina, 8% à nitrofurantoína, 8% à canamicina, 5% à norfloxacina, 4% ao cloranfenicol e 3% às sulfonamidas. Dentre os isolados analisados, 43% apresentaram índice de múltipla resistência a antimicrobianos (MAR igual ou superior a 22%, ou seja, resistência a dois ou mais drogas das nove testadas. Os dados apontam para um risco iminente, tanto pelo isolamento de amostras

  8. First detection of Aeromonas sobria from diarrheal army soldiers in Yunnan garrison%云南战区部队驻地腹泻患者中首次检出温和气单胞菌

    Institute of Scientific and Technical Information of China (English)

    李刚山; 邱薇; 范泉水; 王惠萱; 王意银; 张超雄; 朱姝媛; 朱琼媛; 覃敏; 赵丽芝; 周丽华

    2012-01-01

    目的 对从腹泻患者粪便中分离出的温和气单胞菌进行鉴定,并做毒素原性及致病性研究和建立药敏谱.方法 碱性蛋白胨水增菌,接种碱性琼脂和TCBS平板分离培养,使用弧菌科细菌生化编码系统(第二代GYZ-9V系列)和API-20E生化编码系列对分离菌株进行鉴定,电子显微镜观察形态.毒素原性研究用溶血试验检测溶血素,小白鼠腹腔注射测定致病性,药敏试验采用纸片扩散法.结果 从587例腹泻患者粪便标本分离出9株温和气单胞菌,毒素原性检测具有溶血素,致病性测定,该菌株毒力较强.所做的18种抗生素药敏试验,对13种敏感,2中度敏感,3种耐药.结论 云南战区部队驻地存在温和气单胞菌感染,毒力试验证实,该分离菌是具有较强毒力的菌株,能使小白鼠发病死亡.药敏试验为部队驻地治疗此菌感染时的临床用药提供重要参考.%Objective To differentiate the Aeromonas sobria isolated from diarrheal patients and the toxigenicity and pathogenicity of Aeromonas sobria. Methods Alkaline peptone was used for enrichment and cultured on alkaline agar and TCBS plate, then differentiated with vibriobacterial biochemical identification coding tube system (second generation GYZ-9v) and API-20E biochemical coding identification tube system. Kirby bauer method was used for drug resistance test. Results Nine Aeromonas sobria strains were isolated from 587 diarrheal patients and hemolysin was also detected by toxigenicity test. The pathogenicity of Aeromonas sobria was strong. The snesitivity of Aeromonas sobria to 18 antibiotics were tested and Aeromonas sobria were resistant to three antibiotics, relative sensitive to 2 anbiotics and sensitive to other 13 ones. Conclusion There is Aeromonas sobria contamination in Yunan Military Garrison and some of them possesses relatively strong pathogenicity that could lead to the death of mice. Attention be paid to clinical treatment of Aeromonas

  9. 嗜水气单胞菌防控技术研究进展%A Review of the Method in Prevent and Control the Harm of Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    周宇; 周秋白

    2012-01-01

      Aeromonas hydrophila, Ah is the widely popular conditioned pathogen to people, livestock and aquatic animal. Especaily it can result in bacterial septicemia and others serious damage and numerous deaths to aquatic animal.This paper summarizes the research progress of Aeromonas virulence factors, sensitivity to antibiotics,and prevention and control method with antibiotics, probiotics vaccine and Chinese herbal medicine.%  嗜水气单胞菌(Aeromonas hydrophila, Ah)是我国流行最广泛的一种人、畜及水生动物共患的条件致病菌,该菌对水产养殖动物的危害尤为严重,能导致水产养殖动物细菌性败血症并引起大量死亡。本文总结了嗜水气单胞菌的毒力因子、防治方法的研究进展。其中包括毒力因子、抗生素、中草药、疫苗和益生菌防控等情况。

  10. Aeromonas sp.XJ-6双加氧酶基因的克隆、表达及对酪氨酸的降解%Cloning and Expression of Dioxygenase Gene from Aeromonas sp.XJ-6 and Promoting Degradation of Tyr

    Institute of Scientific and Technical Information of China (English)

    杨杨; 杨江科; 熊炜; 梁建芳; 段魏魏; 晁群芳

    2016-01-01

    目的:从Aeromonas sp.XJ-6中克隆双加氧酶基因,初步探索该酶的功能,为芳香烃化合物的生物降解提供基因资源.方法:PCR扩增双加氧酶基因dio6,并实现该基因在大肠杆菌(Escherichia coli)中的诱导表达.产物经Ni-NTA柱纯化后,通过薄层层析(TLC)和HPLC检测双加氧酶dio6对Tyr的降解效果,再结合LC-MS检测降解产物,并分析其可能的降解途径.结果:Aeromonas sp.XJ-6双加氧酶基因dio6大小为1 194bp;通过金属鳌合亲和层析(MCAC)纯化后dio6表达产物的大小为44.9kDa.双加氧酶dio6对Tyr具有较强的降解作用.TLC和HPLC检测表明,在60μl酶量和30℃反应温度等条件下,Tyr降解较快;Mg2、Ca2略微抑制酶促反应,Mn2+、Zn2、Cu2+、Fe2+、Ca2+促进底物降解,其中Mn2+对双加氧酶影响最大.LC-MS分析表明,在双加氧酶dio6作用下,Tyr被降解为延胡索酸.结论:Aeromonas sp.XJ-6双加氧酶dio6是一种苯环开环酶,为芳香烃化合物的生物降解提供了良好的基因资源.

  11. CP7抗菌蛋白对嗜水气单胞菌的抑杀作用机理%Mechanism of CP7 antibacterial protein against Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    苑园园; 刘清明; 钟杨生; 廖富蘋; 林健荣

    2012-01-01

    [目的]研究多粘类芽孢杆菌(Paenibacillus polymyxa) CP7菌株的抗菌蛋白(CP7ACP)对嗜水气单胞菌的抑杀作用机理,为防治嗜水气单胞菌引起的鱼病提供新的潜在天然药物.[方法]采用抑菌试验、钼锑抗比色法和紫外光谱法研究其对嗜水气单胞菌S12菌株生长、磷泄漏和生物大分子的影响,并利用扫描电镜和透射电镜观察了嗜水气单胞菌细胞结构遭受的破坏作用.[结果]CP7ACP对嗜水气单胞菌的抑菌圈直径约8.1 mm,最小抑菌浓度(MIC)与最小杀菌浓度(MBC)分别为原液浓度的1/8和1/4;嗜水气单胞菌受CP7ACP处理后,电镜观察发现其细胞壁、细胞膜、细胞器以及菌体均受到不同程度的破坏,胞内的生物大分子和磷泄漏明显,基因组DNA发生增色效应.[结论]CP7ACP抑制嗜水气单胞菌生长,可用于防治嗜水气单胞菌引起的鱼病.%[Objective] The efficacy of the CP7 antimicrobial proteins (CP7ACP) to Aeromonas hydrophila was evaluated to provide potential novel natural drug for treating fish disease caused by Aeromonas hydrophila.[Methods] The effect on Growth, phosphorus divulges and biomacromolecule of Aeromonas hydrophila S12 were tested using Antibacterial test, Mo-Sb colorimetry and UV spectroscopy, while destructive effects of Aeromonas hydrophila cell structure by CP7ACP were observed under both scanning electron microscope and transmission electron microscope.[Results] The inhibition zone diameter was about 8.1 mm, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was 1/8 and 1/4 of stock solution respectively.After treated by CP7ACP, electron microscope reveals that cell wall, membrane, organelles and the thallus of Aeromonas hydrophila are subject to different degrees of damage, while intracellular biomacromolecule and phosphorus significantly divulge, genomic DNA become hyperchromic effect.[Conclusion] CP7ACP inhibit the growth of Aeromonas hydrophila, can

  12. Effect of salinity and incubation time of planktonic cells on biofilm formation, motility, exoprotease production, and quorum sensing of Aeromonas hydrophila.

    Science.gov (United States)

    Jahid, Iqbal Kabir; Mizan, Md Furkanur Rahaman; Ha, Angela J; Ha, Sang-Do

    2015-08-01

    The aim of this study was to determine the effect of salinity and age of cultures on quorum sensing, exoprotease production, and biofilm formation by Aeromonas hydrophila on stainless steel (SS) and crab shell as substrates. Biofilm formation was assessed at various salinities, from fresh (0%) to saline water (3.0%). For young and old cultures, planktonic cells were grown at 30 °C for 24 h and 96 h, respectively. Biofilm formation was assessed on SS, glass, and crab shell; viable counts were determined in R2A agar for SS and glass, but Aeromonas-selective media was used for crab shell samples to eliminate bacterial contamination. Exoprotease activity was assessed using a Fluoro™ protease assay kit. Quantification of acyl-homoserine lactone (AHL) was performed using the bioreporter strain Chromobacterium violaceum CV026 and the concentration was confirmed using high-performance liquid chromatography (HPLC). The concentration of autoinducer-2 (AI-2) was determined with Vibrio harveyi BB170. The biofilm structure at various salinities (0-3 %) was assessed using field emission electron microscopy (FESEM). Young cultures of A. hydrophila grown at 0-0.25% salinity showed gradual increasing of biofilm formation on SS, glass and crab shell; swarming and swimming motility; exoproteases production, AHL and AI-2 quorum sensing; while all these phenotypic characters reduced from 0.5 to 3.0% salinity. The FESEM images also showed that from 0 to 0.25% salinity stimulated formation of three-dimensional biofilm structures that also broke through the surface by utilizing the chitin surfaces of crab, while 3% salinity stimulated attachment only for young cultures. However, in marked contrast, salinity (0.1-3%) had no effect on the stimulation of biofilm formation or on phenotypic characters for old cultures. However, all concentrations reduced biofilm formation, motility, protease production and quorum sensing for old culture. Overall, 0-0.25% salinity enhanced biofilm formation

  13. Formação de biofilme em aço inoxidável por Aeromonas hydrophila e Staphylococcus aureus usando leite e diferentes condições de cultivo Biofilm formation by Aeromonas hydrophila and Staphylococcus aureus on stainless steel using milk and different conditions of cultivation

    Directory of Open Access Journals (Sweden)

    Cleube Andrade Boari

    2009-12-01

    Full Text Available O objetivo desta pesquisa consistiu em avaliar a formação de biofilme em aço inoxidável por Aeromonas hydrophila e Staphylococcus aureus usando leite e diferentes condições de cultivo. As variáveis em estudo consistem no cultivo monoespécie e combinado, dos referidos microrganismos e nas temperaturas de 4, 7 e 18 °C. Recipientes contendo 1000 mL de leite, densidade populacional de 10(5 UFC.mL-1 de cada microrganismo e 10 cupons de aço inoxidável (10 × 20 mm foram lacrados e armazenados, sob agitação de 60 rpm, por um período de 10 dias. As análises ocorreram a cada 48 horas. Células sésseis de A.hydrophila e S. aureus foram enumeradas através do plaqueamento seletivo em ágar m-Aeromonas selective e Baird-Parker, respectivamente. Estudos sobre o tempo de geração, enumeração de células planctônicas e observação dos cupons através da microscopia eletrônica de varredura foram conduzidos. S. aureus, em monocultivo, formou biofilme a 18 °C e a 7 °C. Para 4 °C, foi observado um processo de adesão. A presença de A. hydrophila reduziu o desempenho de S. aureus. Nesta condição de cultivo multiespécie houve formação de biofilme a 18 °C. A. hydrophila, tanto em monocultivo quanto em presença de S. aureus, formou biofilme em todas as condições pesquisadas.The aim of this research was to verify the capability of biofilm formation on stainless steel by Aeromonas hydrophila and Staphylococcus aureus using milk and different conditions of cultivation. The variables consisted in mono and multi-species cultivation of these microorganisms and in the temperatures of 4, 7 and 18 °C. Containers containing 1000 mL of milk, population density of 10(5 CFU.mL-1 of each microorganism, and ten suspended chips of stainless steel AISI 304 (10 × 20 mm were used to seal up and storage, under 60 rpm of agitation for 10 days. The analyses were conducted every 48 hours. Sessile cells of A. hydrophila and S. aureus and were enumerated

  14. Transcriptomes analysis of Aeromonas molluscorum Av27 cells exposed to tributyltin (TBT): Unravelling the effects from the molecular level to the organism.

    Science.gov (United States)

    Cruz, Andreia; Rodrigues, Raquel; Pinheiro, Miguel; Mendo, Sónia

    2015-08-01

    Aeromonas molluscorum Av27 cells were exposed to 0, 5 and 50 μM of TBT and the respective transcriptomes were obtained by pyrosequencing. Gene Ontology revealed that exposure to 5 μM TBT results in a higher number of repressed genes in contrast with 50 μM of TBT, where the number of over-expressed genes is greater. At both TBT concentrations, higher variations in gene expression were found in the functional categories associated with enzymatic activities, transport/binding and oxidation-reduction. A number of proteins are affected by TBT, such as the acriflavin resistance protein, several transcription-related proteins, several Hsps, ABC transporters, CorA and ZntB and other outer membrane efflux proteins, all of these involved in cellular metabolic processes, important to maintain overall cell viability. Using the STRING tool, several proteins with unknown function were related with others involved in degradation processes, such as the pyoverdine chromophore biosynthetic protein, that has been described as playing a role in the Sn-C cleavage of organotins. This approach has allowed a better understanding of the molecular effects of exposure of bacterial cells to TBT. Furthermore it contributes to the knowledge of the functional genomic aspects of bacteria exposed to this pollutant. Furthermore, the transcriptomic data gathered, and now publically available, constitute a valuable resource for comparative genome analysis.

  15. Detection of Aeromonas hydrophila DNA oligonucleotide sequence using a biosensor design based on Ceria nanoparticles decorated reduced graphene oxide and Fast Fourier transform square wave voltammetry.

    Science.gov (United States)

    Jafari, Safiye; Faridbod, Farnoush; Norouzi, Parviz; Dezfuli, Amin Shiralizadeh; Ajloo, Davood; Mohammadipanah, Fatemeh; Ganjali, Mohammad Reza

    2015-10-01

    A new strategy was introduced for ssDNA immobilization on a modified glassy carbon electrode. The electrode surface was modified using polyaniline and chemically reduced graphene oxide decorated cerium oxide nanoparticles (CeO2NPs-RGO). A single-stranded DNA (ssDNA) probe was immobilized on the modified electrode surface. Fast Fourier transform square wave voltammetry (FFT-SWV) was applied as detection technique and [Ru(bpy)3](2+/3+) redox signal was used as electrochemical marker. The hybridization of ssDNA with its complementary target caused a dramatic decrease in [Ru(bpy)3](2+/3+) FFT-SW signal. The proposed electrochemical biosensor was able to detect Aeromonas hydrophila DNA oligonucleotide sequence encoding aerolysin protein. Under optimal conditions, the biosensor showed excellent selectivity toward complementary sequence in comparison with noncomplementary and two-base mismatch sequences. The dynamic linear range of this electrochemical DNA biosensor for detecting 20-mer oligonucleotide sequence of A. hydrophila was from 1 × 10(-15) to 1 × 10(-8) mol L(-1). The proposed biosensor was successfully applied for the detection of DNA extracted from A. hydrophila in fish pond water up to 0.01 μg mL(-1) with RSD of 5%. Besides, molecular docking was applied to consider the [Ru(bpy)3](2+/3+) interaction with ssDNA before and after hybridization.

  16. Catecholamine-stimulated Growth of Aeromonas hydrophila Requires the TonB2 Energy Transduction System but is Independent of the Amonabactin Siderophore

    Directory of Open Access Journals (Sweden)

    Yuhao Dong

    2016-12-01

    Full Text Available The growth-stimulating effects of catecholamine stress hormones have been demonstrated in many pathogens. However, catecholamine-induced growth and its underlying mechanisms remain poorly understood in Aeromonas hydrophila. The present study sought to demonstrate that norepinephrine (NE, epinephrine (Epi, dopamine (Dopa and L-dopa stimulate the growth of A. hydrophila in iron-restricted media containing serum. NE exhibited the strongest growth stimulation, which could be blocked by adrenergic antagonists. Furthermore, it was demonstrated that NE could sequester iron from transferrin, thereby providing a more accessible iron source for utilization by A. hydrophila. The deletion of the amoA gene associated with amonabactin synthesis revealed that the amonabactin siderophore is not required for NE-stimulated growth. However, the deletion of the TonB2 energy transduction system resulted in the loss of growth promotion by NE, indicating that a specific TonB-dependent outer membrane receptor might be involved in the transport of iron from transferrin. Collectively, our data show that catecholamine sensing promotes the growth of A. hydrophila in a manner that is dependent on the TonB2 energy transduction system.

  17. Effects of hirami lemon, Citrus depressa Hayata, leaf meal in diets on the immune response and disease resistance of juvenile barramundi, Lates calcarifer (bloch), against Aeromonas hydrophila.

    Science.gov (United States)

    Shiu, Ya-Li; Lin, Hsueh-Li; Chi, Chia-Chun; Yeh, Shinn-Pyng; Liu, Chun-Hung

    2016-08-01

    The present study was conducted to evaluate the dietary supplementation of leaf meal from Citrus depressa Hayata on the growth, innate immune response, and disease resistance of juvenile barramundi, Lates calcarifer. Four diets were formulated to contain 0% (control), 1% (C1), 3% (C3), and 5% (C5) leaf meal, respectively. During a 56 d feeding trial, fish survival, growth performance, and feed efficiency were not significantly different among all groups. For immune response, respiratory burst, superoxide dismutase and lysozyme activities were not significantly different among all groups. However, fish fed the C5 diet for 56 d had significantly higher phagocytic activity. Also, fish fed C3 and C5 diets had significantly higher Mx gene expressions in spleens and head kidneys with nerve necrosis virus injections after 24 h. Disease resistance against Aeromonas hydrophila was increased by the C5 diet. In this study, barramundi fed on a diet containing 5% C. depressa Hayata leaf meal had significantly better innate immune response and disease resistance against A. hydrophila.

  18. Antimicrobial effect of the Biotronic® Top3 supplement and efficacy in protecting rainbow trout (Oncorhynchus mykiss) from infection by Aeromonas salmonicida subsp. salmonicida.

    Science.gov (United States)

    Menanteau-Ledouble, Simon; Krauss, Ines; Goncalves, Rui Alexandre; Weber, Barbara; Santos, Gonçalo Abreu; El-Matbouli, Mansour

    2017-03-18

    Demand for more environmentally friendly practices have led to the adoption of several feed supplements by the fish farming industry. In the present study, we investigated a commercially available formula that includes a mixture of three compounds: organic acids, a phytochemical and Biomin® Permeabilizing Complex. This mixture demonstrated antimicrobial properties in vitro and was able to inhibit growth of multiple species of aquatic bacterial pathogens, including Aeromonas salmonicida. Bacterial challenge was performed using A. salmonicida and three exposure routes: intra-peritoneal injection, immersion, and cohabitation. Mortality rates following infection by injection were significantly decreased in the fish that had received the supplemented feed. Fish infected through the other routes did not show a significant difference in mortality. In term of farming performance, while the fish that had received the feed supplement showed an improvement in weight gain and final weight, these changes were not found to be statistically significant. Similarly, no significant difference was observed in the feed conversion ratio. The results of this study suggest that this feed supplement may be effective at protecting rainbow trout from fish furunculosis.

  19. Catecholamine-Stimulated Growth of Aeromonas hydrophila Requires the TonB2 Energy Transduction System but Is Independent of the Amonabactin Siderophore

    Science.gov (United States)

    Dong, Yuhao; Liu, Jin; Pang, Maoda; Du, Hechao; Wang, Nannan; Awan, Furqan; Lu, Chengping; Liu, Yongjie

    2016-01-01

    The growth-stimulating effects of catecholamine stress hormones have been demonstrated in many pathogens. However, catecholamine-induced growth and its underlying mechanisms remain poorly understood in Aeromonas hydrophila. The present study sought to demonstrate that norepinephrine (NE), epinephrine (Epi), dopamine (Dopa), and L-dopa stimulate the growth of A. hydrophila in iron-restricted media containing serum. NE exhibited the strongest growth stimulation, which could be blocked by adrenergic antagonists. Furthermore, it was demonstrated that NE could sequester iron from transferrin, thereby providing a more accessible iron source for utilization by A. hydrophila. The deletion of the amoA gene associated with amonabactin synthesis revealed that the amonabactin siderophore is not required for NE-stimulated growth. However, the deletion of the TonB2 energy transduction system resulted in the loss of growth promotion by NE, indicating that a specific TonB-dependent outer membrane receptor might be involved in the transport of iron from transferrin. Collectively, our data show that catecholamine sensing promotes the growth of A. hydrophila in a manner that is dependent on the TonB2 energy transduction system. PMID:28018865

  20. 草鱼嗜水气单胞菌候选疫苗%A candidate Vaccine for grass carp Aeromonas hydrophila disease

    Institute of Scientific and Technical Information of China (English)

    邱并生

    2011-01-01

    @@ 草鱼是我国淡水养殖最重要的鱼类之一,其养殖过程易受细菌性或病毒性病原的侵袭,嗜水气单胞菌Aeromonas hydrophila是引发其暴发性败血症的主要细菌性病原之一,对草鱼养殖造成严重的威胁.因此研制疫苗以实现免疫预防极为重要.传统的嗜水气单胞菌疫苗有灭活全菌疫苗、弱毒疫苗等,但其成分复杂、易对鱼体产生较大影响,且存在回复突变的风险,同时嗜水气单胞菌复杂的血清型也影响着其免疫保护效果.

  1. Research Advances of Virulence Factors in Bacterium Aeromonas hydrophila%嗜水气单胞菌毒力因子研究进展

    Institute of Scientific and Technical Information of China (English)

    李绍戊; 卢彤岩

    2013-01-01

    An opportunistic pathogenic bacterium Aeromonas hydrophila infecting human, livestock and aquatic animals is widely found in nature. The damage of the bacterium to animals is involved in secretion and expression of virulent factors such as exotoxin, outer-membrane proteins and surface molecules. Therefore, knowledge of virulent genes in the bacterium will be helpful to further understanding of the mechanisms of the pathogenesis as well as to exploration of effective methods of prophylaxis and therapy the diseases caused by the bacterium. Here the research advances on the virulent factors in bacterium A. hydrophila were reviewed in this paper.%嗜水气单胞菌是一种广泛分布于自然界中的革兰氏阴性菌,是一种人-兽-鱼共患病的条件致病菌。其危害的产生与其外毒素、胞外蛋白酶及表面分子等毒力因子的分泌、表达相关。研究其毒力因子有利于深入了解该菌的致病机理,探索有效的防治方法。本文综述了嗜水气单胞菌毒力因子的相关研究进展。

  2. Trigonella foenum-graceum (Seed Extract Interferes with Quorum Sensing Regulated Traits and Biofilm Formation in the Strains of Pseudomonas aeruginosa and Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Fohad Mabood Husain

    2015-01-01

    Full Text Available Trigonella foenum-graecum L. (Fenugreek is an important plant of the Leguminosae family known to have medicinal properties. However, fraction based antiquorum sensing and antibiofilm activities have not been reported from this plant. In the present study T. foenum-graecum seed extract was sequentially fractionated and sub-MICs were tested for above activities. The methanol fraction of the extract demonstrated significant inhibition of AHL regulated virulence factors: protease, LasB elastase, pyocyanin production, chitinase, EPS, and swarming motility in Pseudomonas aeruginosa PAO1 and PAF79. Further, QS dependent virulence factor in the aquatic pathogen Aeromonas hydrophila WAF38 was also reduced. Application of T. foenum-graecum seed extract to PAO1, PAF79, and WAF38 decreased the biofilm forming abilities of the pathogens by significant levels. The extract also exhibited reduced AHL levels and subsequent downregulation of lasB gene. In vivo study showed an enhanced survival of PAO1-preinfected C. elegans after treatment with extract at 1 mg/mL. Further, the major compound detected by GC-MS, caffeine, reduced the production of QS regulated virulence factors and biofilm at 200 µg/mL concentration indicating its role in the activity of the methanol extract. The results of the present study reveal the potential anti-QS and antibiofilm property of T. foenum-graceum extract and caffeine.

  3. EVALUASI PEMBERIAN PROBIOTIK BACILLUS PADA MEDIA PEMELIHARAAN TERHADAP LAJU PERTUMBUHAN DAN PERUBAHAN HISTOPATOLOGI IKAN LELE DUMBO (Clarias gariepinus YANG DIINFEKSI Aeromonas hydrophila

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    Angela Mariana Lusiastuti

    2016-12-01

    Full Text Available The aim of this study was to evaluate the addition of a probiotic Bacillus on culture medium through growth rate and histopathological change in African Catfish who was infected by Aeromonas hydrophila. The study consisted of five treatments such as the addition of probiotic Bacillus ND2, Bacillus P4I2, Bacillus ND2 + Bacillus P4I2 (Kom, positive control (K+ and negative control (K- (without probiotic addition. African Catfish (13.354±2.8 g was maintained in 15 aquariums (40 L in volume with 30 fishes each for 30 days. Probiotic bacteria was applied in water once a day, whereas pathogenic bacteria A. hydrophila  (103 CFU/mL were added once in earlier treatment (except for the negative control as assumption that A. hydrophila will shape up quorum sensing in unfortunate condition. The result showed that the highest spesific growth rate in the treatment of Bacillus ND2 probiotics (1,708 ± 0.114%. Histopathology showed that damaged of liver dan kidney in probiotics treatment were lightner than positive control (K+.  The addition of Bacillus P4I1 (104 CFU/mL efective to increased the spesific growth rate of African Catfish and prevent the damage of liver and kidney of African Catfish was infected by Aeromoniasis.

  4. Efficacy of an extract from garlic, Allium sativum, against infection with the furunculosis bacterium, Aeromonas salmonicida, in rainbow trout, Oncorhynchus mykiss

    Science.gov (United States)

    Breyer, Kate E.; Getchell, Rodman G.; Cornwell, Emily R.; Wooster, Gregory A.; Ketola, H. George; Bowser, Paul R.

    2015-01-01

    Juvenile rainbow trout, Oncorhynchus mykiss, were fed diets containing 0, 0.5, 1.0, and 2.0% of a garlic extract, challenged with a modified 50% lethal dose of Aeromonas salmonicida and monitored for 28 d. There were significant increases in survival of trout fed 0.5 and 1.0% garlic extract as compared to the control and 2.0% garlic extract groups. A target animal safety study was performed at varying increments using the target dose of 0.5% garlic extract at 0× (0% garlic extract), 1× (0.5% garlic extract), 3× (1.5% garlic extract), and 5× (2.5% garlic extract) for 3× (6 wk) the duration of the original study. There was a significant increase in the level of circulating lymphocytes and a significant decrease in the level of circulating monocytes. The latter correlated to an increased level of pigment-containing macrophage centers within the renal tissue as garlic extract dosing increased, denoting a potential deleterious inflammatory effect as macrophage infiltration became severe at the highest dose. These studies suggest that feeding low-dose (0.5% or 1.0%) garlic extract improves survivability in rainbow trout when challenged with A. salmonicida and appears safe; however, higher levels do not appear to be effective and may cause deleterious effects on health.

  5. Isolation and identification of Aeromonas and analysis for drug resistance from diarrhea samples in Shanghai Pudong New Area%浦东新区腹泻样本中气单胞菌的分离鉴定及耐药性分析

    Institute of Scientific and Technical Information of China (English)

    王闻卿; 赵冰; 詹铭

    2011-01-01

    Objective: To find out the incidence of Aeromonas infection and the drug resistance from diarrhea cases in Shanghai Pudong New Area. Methods: Detection Aeromonas in feces specimens from 1245 diarrhea samples in 2 monitoring sites; the positive strains were tested for sensitivity to 10 kinds of antibiotics by K - B method. Results: 93 stains(7.47% ) of Aeromonas were isolated, including 26 strains of Aeromonas sobria,63 strains of Aeromonas hydrophila and 4 strains of Aeromonas caviae. The detection rate of infection during June to October revealed higher prevelence rate. Antimicrobial susceptibility tests showed more than 80% strains were susceptible to Gentamicin, Ciprofloxacin, Amikacin, Cefotaxime while resistant to Ampicillin, Trimethoprim - sulfamethoxazole, Cefalotin, Nalidixic acid at deferent levels. Conclusion: Infection rate of Aeromonas varied in season, having close relationship with diarrhea in summer and autumn. Continuous Monitoring to Aeromonas and its drug resistance has guiding significance for prevention and treatment of diarrhea disease.%目的:了解上海浦东新区感染性腹泻病人气单胞菌的感染及耐药情况,为相关防控策略的制定提供科学依据.方法:对2010年上海市浦东新区2个监测点,1245件急性腹泻样本进行气单胞菌检测,阳性菌进行药物敏感试验.结果:从1245件标本中检出气单胞菌93株,阳性率为7.47%,其中嗜水气单胞63株,温和气单胞26株,豚鼠气单胞4株.6月-8月份为高峰期.药敏试验结果:80%以上菌株对庆大,环丙沙星,阿米卡星、头孢噻肟敏感,对氨苄西林,复方新诺明、四环素、头孢噻吩、萘啶酸不同程度耐药.结论:气单胞菌感染存在季节性差异,与夏秋季腹泻关系密切.持续对气单胞菌及其耐药性的监测对细菌性腹泻病的预防与治疗具有指导意义.

  6. Characterization and multilocus sequence typing of Aeromonas strains isolated in Tianjin area%天津地区气单胞菌分离株的鉴定与多位点序列分型

    Institute of Scientific and Technical Information of China (English)

    李倩; 杨洪江; 何洋; 石礼涛

    2013-01-01

    [目的]研究气单胞菌菌株分类情况,并分析其致病性.[方法]采集环境样品和鱼类标本,分离并鉴定气单胞菌菌株,并运用多位点序列分型(Multilocus sequence typing,MLST)方法进行分类研究,利用PCR和测序方法分析毒力基因Aera、Hly、Aha1、GCAT和Nuc的分布.[结果]通过对分离菌株的16S rRNA基因进行分析,确认属于4种不同气单胞菌的7个分离株.发现所有菌株至少有1种毒力基因阳性,其中3株具有4种毒力基因.药物敏感实验显示,6株分离株对3种或3种以上抗菌素具有多重耐药性.最后,对看家基因gyrB、groL、gltA、metG、ppsA和recA进行分析,与MLST数据库中的等位基因序列比对,发现7株分离株均为新的不同的序列型(Sequence type,ST).[结论]气单胞菌具有较高的遗传多样性.%[Objective] To study the classification of Aeromonas genus and its pathogenicity.[Methods] Various environmental samples were collected,Aeromonas strains were isolated and characterized,and multilocus sequence typing (MLST) method was adopted to classify the isolates.[Results] Among the isolates 7 Aeromonas strains were identified,belonging to 4 different species of the genus Aeromonas based on 16S rRNA sequence analysis.Furthermore,5 major virulence genes including Aera,Hly,Ahal,GACT and Nuc were detected in the isolates by PCR and sequencing methods.All strains contained at least one virulence gene,and 3 of them contained 4 virulence genes,respectively.Antibiotic susceptibility test showed that 6 strains exhibited multiple drug resistances to at least 3 antibiotics.Finally,6 housekeeping genes (gyrB,groL,gltA,metG,ppsA,and recA) were chosen for the MLST analysis by PCR and sequencing.Allele sequences were aligned by searching the MLST database.All 7 Aeromonas strains were assigned a new ST number.[Conclusion] High genetic diversity existed in Aeromonas strains.

  7. 巨蜥嗜水气单胞菌和保科爱德华菌混合感染诊治的初步研究%Infectious disease caused by Aeromonas hydrophila and Edwardsiella tarda in Varanus bengalensis benalensis

    Institute of Scientific and Technical Information of China (English)

    徐正强; 沈莉萍; 王建; 沈怡萱

    2007-01-01

    从患病巨蜥(Varanus bengalensis bengalensis)的肝脏中分离出2种致病菌,经鉴定为嗜水气单胞菌Aeromonas hydrophila和保科爱德华菌Edwardsiella tarda.药敏试验结果表明,该病菌对恩诺沙星、先锋必、环丙沙星、丁胺卡那霉素高敏,对青霉素、林可霉素等低敏.

  8. 暹罗斗鱼致病性嗜水气单胞菌的分离·鉴定及药敏试验%Isolation, Identification and Drug Sensitivity Test of Pathogenic Aeromonas hydrophila from Betta splendens Regan

    Institute of Scientific and Technical Information of China (English)

    杨宁; 黄海; 张希; 魏赟; 巫火连

    2012-01-01

    [Objective] The research aimed to discuss the disease cause of Betta splcnders Regan and the prevention and control methods of its diseases and pests. [Method] The pathogenic bacteria of B, splenders were isolated and identified by determining die physiological and biochemical indices and 16 S rDNA sequencing. And the drug sensitivity test was made. [Result] Strain DY001 was the pathogenic bacteria that caused Aeromonas hydrophila disease of B. splenders. Strain DY001 was identified as Aeromonas hydrophila. The median lethal dose (LD50) of this pathogeny to B. splenders was 0. 04 × 106 CFU/g. The results of drug sensitivity test showed that this pathogenic bacteria was sensitive to azithromycin, ofloxacin, norfloxacin, compound sinomin, ceftriaxone, trimethoprim, chloramphenicol and other antibiotics. [Conclusion] Aeromonas hydropkila was the pathogenic bacteria that caused the disease incidence of B. splenders. The results of drug sensitivity test could provide references for the disease prevention and control of B. splenders.%[目的]探讨暹罗斗鱼的发病原因和病害防治方法.[方法]对暹罗斗鱼的病原菌进行分离,并通过生理生化指标测定和16S rDNA测序对其鉴定,同时进行药敏试验.[结果]菌株DY001为暹罗斗鱼嗜水气单胞菌病的病原菌.经鉴定,确定菌株DY001为嗜水气单胞菌(Aeromonas hydrophila).该病原菌对暹罗斗鱼的半致死量(LD50)为0.04×106 CFU/g.药敏试验结果表明,病原菌对阿奇霉素、奥复星、氟哌酸、复方新诺明、菌必治、甲氧苄啶和氯霉素等抗生素敏感.[结论]嗜水气单胞菌是引起此次暹罗斗鱼发病的病原菌,而药敏试验结果将为其防治提供参考.

  9. Effects of marine silages enriched with Lactobacillus sakei 5-4 on haemato-immunological and growth response in Pacific red snapper (Lutjanus peru) exposed to Aeromonas veronii.

    Science.gov (United States)

    Reyes-Becerril, Martha; Ascencio-Valle, Felipe; Macias, María Esther; Maldonado, Minerva; Rojas, Maurilia; Esteban, María Ángeles

    2012-10-01

    Combined effects of marine silages enriched with Lactobacillus sakei 5-4 were evaluated on growth performance, immune activity and disease resistance of Pacific red snapper (Lutjanus peru) against Aeromonas veronii infection. The experimental fish were divided into three groups which were fed with each one of the following diets: silage-probiotic-free diet (control, C group), Pacific creole-fish silage diet supplemented with live L. sakei (10(6) CFU g(-1)) (FSLact group) and Humboldt squid silage diet supplemented with live L. sakei (10(6) CFU g(-1)) (SSLact group) for 6 weeks. After 6 weeks, fish were immunocompromised with pathogenic A. veronii and spleen and liver samples were processed for histopathological studies. Generally, the results showed enhanced growth performance in fish fed the diet containing SSLact at 6 and 7 weeks compared with fish fed control diet. Addition of SSLact had an increase in plasmatic protein at week 6 and post-challenge. Hemoglobin concentration increased after challenge in fish fed with SSLact compared to control group. At week 6 and post-challenge the results indicated that, the fish groups which received diet supplemented with SSLact revealed significant increase in humoral immune parameters. Histologically, fish fed C diets showed marked fatty degeneration and great activation of melanomacrophage centers compare with SSLact and FSLact groups. These results support the idea that the marine silages with squid as protein source enriched or combined with L. sakei 5-4 increases the body weight and stimulates the physiological and humoral immune parameters in Pacific red snapper infected with A. veronii.

  10. In vivo bactericidal effect of Melaleuca alternifolia essential oil against Aeromonas hydrophila: Silver catfish (Rhamdia quelen) as an experimental model.

    Science.gov (United States)

    F Souza, Carine; Baldissera, Matheus D; A Vaucher, Rodrigo; Lopes, Leonardo Q S; Vizzotto, Bruno S; Raffin, Renata P; Santos, Roberto C V; L da Veiga, Marcelo; U M da Rocha, Maria Izabel; Stefani, Lenita M; Baldisserotto, Bernardo

    2016-09-01

    Aeromonas hydrophila is one of the main causative agent of high mortality and significative economic losses in aquaculture and has become increasingly resistant to conventional antibiotics. One feasible alternative to control and treat it is the use of essential oils. This study aimed to evaluate A. hydrophila susceptibility to tea tree oil (TTO-Melaleuca alternifolia) in vivo, and the effect of this treatment. In vivo tests were performed using silver catfish (Rhamdia quelen) as the experimental model. Silver catfish were treated with TTO at 25 and 50 μL/L for seven days before infection. After seven days, the fish were inoculated with A. hydrophila via intramuscularly. Treatment with TTO at 50 μL/L was able to extend longevity of infected fish, and showed 88% of therapeutic success, even though it did not show curative efficacy. TTO treatment was not toxic under these tested concentrations, since biomarkers of hepatic and renal functions were not affected, and the concentration of 50 μL/L was able to prevent increased levels of aspartate aminotransferase. There was no significative differences regarding hematological parameters (p < 0.05). Treatment with TTO 50 μL/L was able to reduce histopathological alterations usually caused by this type of bacteria in the gills, but it was unable to reduce hepatic histopathological alterations. Our results showed, for the first time, that TTO has high activity against A. hydrophila and proved to be a natural alternative to prevent and control this pathogen.

  11. Effectiveness of sal deoiled seed cake as an inducer for protease production from Aeromonas sp. S1 for its application in kitchen wastewater treatment.

    Science.gov (United States)

    Saini, Vandana; Bhattacharya, Amrik; Gupta, Anshu

    2013-08-01

    The present study is an attempt to demonstrate the feasibility of sal (Shorea robusta) deoiled cake--a forest-based industrial by-product--as a cheaper media supplement for augmented protease production from Aeromonas sp. S1 and application of protease in the treatment of kitchen wastewater. Under optimized conditions, protease production could successfully be enhanced to 5.13-fold (527.5 U mL(-1)) on using sal deoiled seed cake extract (SDOCE), as medium additive, compared to an initial production of 102.7 U mL(-1) in its absence. The culture parameters for optimum production of protease were determined to be incubation time (48 h), pH (7.0), SDOCE concentration (3 % (v/v)), inoculum size (0.3-0.6 % (v/v)), and agitation rate (100 rpm). The enzyme was found to have an optimum pH and temperature of 8.0 and 60 °C, respectively. The protease preparation was tested for treatment of organic-laden kitchen wastewater. After 96 h of wastewater treatment under static condition, enzyme preparation was able to reduce 74 % biological oxygen demand, 37 % total suspended solids, and 41 % oil and grease. The higher and improved level of protease obtained using sal deoiled seed cake-based media hence offers a new approach for value addition to this underutilized biomass through industrial enzyme production. The protease produced using this biomass could also be used as pretreatment tool for remediation of organic-rich food wastewater.

  12. 病原维氏气单胞菌的分离鉴定研究%Isolation and identification of pathogenic Vickers Aeromonas

    Institute of Scientific and Technical Information of China (English)

    李靖; 王桂青

    2011-01-01

    Aeromonas as well as a serious pathogen of human and aquatic economic animals.this article from a turtle farm in Qingdao unexplained deaths of a pathogen isolated lesion site HBJY01,identification of the bacterium.Combination of traditional identification methods using the 16S rRNA and gyrB HBJY01 cloning method to identify the bacteria species.The results show that traditional identification methods and identification of molecular biology methods were consistent.Experimental results show that artificial infection HBJY01 infect healthy turtle,the mortality rate of 100%,symptoms and unexplained death of roughly the same turtle.Whichever is the same pathogen isolated from the liver lesions.%气单胞菌(Aeromonas)是一类人和水产经济动物的严重致病菌,本文从青岛某中华鳖养殖场不明原因死亡病例的病灶部位分离一株病原菌HBJY01,对该菌进行鉴定。采用传统鉴定方法结合HBJY01的16S rRNA和gyrB基因克隆的方法,鉴定该菌的属种(Aeromonas)。结果表明传统鉴定方法与分子生物学方法鉴定结果一致。人工感染实验结果表明HBJY01感染健康中华鳖,死亡率100%,症状与不明原因死亡的中华鳖大体相同。取其病变肝脏分离到相同病原菌。

  13. Steelhead trout Oncorhynchus mykiss metabolic rate is affected by dietary Aloe vera inclusion but not by mounting an immune response against formalin-killed Aeromonas salmonicida.

    Science.gov (United States)

    Zanuzzo, F S; Urbinati, E C; Nash, G W; Gamperl, A K

    2015-07-01

    The oxygen consumption (MO2) of two groups of 10° C acclimated steelhead trout Oncorhynchus mykiss was measured for 72 h after they were given a 100 µl kg(-1) intraperitoneal injection of formalin-killed Aeromonas salmonicida (ASAL) or phosphate-buffered saline (PBS). In addition, plasma cortisol levels were measured in fish from both groups prior to, and 1 and 3 h after, they were given a 30 s net stress. The first group was fed an unaltered commercial diet for 4 weeks, whereas the second group was fed the same diet but with 0·5% (5 g kg(-1) ) Aloe vera powder added; A. vera has potential as an immunostimulant for use in aquaculture, but its effects on basal and acute phase response (APR)-related metabolic expenditures and stress physiology, are unknown. Injection of ASAL v. PBS had no measurable effect on the MO2 of O. mykiss indicating that the APR in this species is not associated with any net increase in energy expenditure. In contrast, incorporating 0·5% A. vera powder into the feed decreased routine metabolic rate by c. 8% in both injection groups and standard metabolic rate in the ASAL-injected group (by c. 4 mg O2 kg(-1) h(-1) ; 5%). Aloe vera fed fish had resting cortisol levels that were approximately half of those in fish on the commercial diet (c. 2·5 v. 5·0 ng ml(-1) ), but neither this difference nor those post-stress reached statistical significance (P > 0·05).

  14. Role of various enterotoxins in Aeromonas hydrophila-induced gastroenteritis: generation of enterotoxin gene-deficient mutants and evaluation of their enterotoxic activity.

    Science.gov (United States)

    Sha, Jian; Kozlova, E V; Chopra, A K

    2002-04-01

    Three enterotoxins from the Aeromonas hydrophila diarrheal isolate SSU have been molecularly characterized in our laboratory. One of these enterotoxins is cytotoxic in nature, whereas the other two are cytotonic enterotoxins, one of them heat labile and the other heat stable. Earlier, by developing an isogenic mutant, we demonstrated the role of a cytotoxic enterotoxin in causing systemic infection in mice. In the present study, we evaluated the role of these three enterotoxins in evoking diarrhea in a murine model by developing various combinations of enterotoxin gene-deficient mutants by marker-exchange mutagenesis. A total of six isogenic mutants were prepared in a cytotoxic enterotoxin gene (act)-positive or -negative background strain of A. hydrophila. We developed two single knockouts with truncation in either the heat-labile (alt) or the heat-stable (ast) cytotonic enterotoxin gene; three double knockouts with truncations of genes encoding (i) alt and ast, (ii) act and alt, and (iii) act and ast genes; and a triple-knockout mutant with truncation in all three genes, act, alt, and ast. The identity of these isogenic mutants developed by double-crossover homologous recombination was confirmed by Southern blot analysis. Northern and Western blot analyses revealed that the expression of different enterotoxin genes in the mutants was correspondingly abrogated. We tested the biological activity of these mutants in a diet-restricted and antibiotic-treated mouse model with a ligated ileal loop assay. Our data indicated that all of these mutants had significantly reduced capacity to evoke fluid secretion compared to that of wild-type A. hydrophila; the triple-knockout mutant failed to induce any detectable level of fluid secretion. The biological activity of selected A. hydrophila mutants was restored after complementation. Taken together, we have established a role for three enterotoxins in A. hydrophila-induced gastroenteritis in a mouse model with the greatest

  15. Hematologia e sinais clínicos de Piaractus mesopotamicus infectados experimentalmente com Aeromonas hydrophila - DOI: 10.4025/actascibiolsci.v31i1.308 Hematology and clinical signs of Piaractus mesopotamicus experimentally infected by Aeromonas hydrophila - DOI: 10.4025/actascibiolsci.v31i1.308

    Directory of Open Access Journals (Sweden)

    Flávio Ruas Moraes

    2009-04-01

    Full Text Available Este ensaio teve como objetivo avaliar as respostas hematológicas e a ocorrência de sinais clínico-patológicos de Piaractus mesopotamicus infectados experimentalmente por Aeromonas hydrophila. Foram utilizados 324 pacus, P. mesopotamicus, com peso de 102,84 ± 27,1 g, distribuídos em 27 caixas de 300 L de capacidade, sendo 14 peixes caixa-1. Os peixes foram mantidos nas caixas durante um mês, recebendo dieta balanceada, período em que se evitou qualquer tipo de manejo estressante. Passado esse período, foram infectados com 6 x 106 UFC de A. hydrophila, injetada via intraperitoneal. As coletas e análises de sangue foram realizadas 24h antes da infecção experimental e 24h após a infecção. Os resultados permitem concluir que a infecção por A. hydrophila em P. mesopotamicus é caracterizada por escurecimento da derme e sinais clínicos-patológicos relacionados à hemorragia, anemia normocítica-hipocrômica, redução nos níveis de proteínas, globulinas plasmáticas e eosinófilos, leucopenia, linfopenia, trombocitopenia, neutrofilia e monocitose.The purpose of this study was to evaluate the hematological response and clinical sign of Piaractus mesopotamicus infected by Aeromonas hydrophila. Were used 324 pacus, Piaractus mesopotamicus weighing 102.84 ± 27.1 g distributed in 27 tanks with 300 L of capacity, 14 fish per tank. The fish were kept in the tanks during one month, receiving appropriate diet. In this period was avoid stressing management. After this period, the fish were infected with 6 × 108 CFU of A. hydrophila/fish, injected intraperitoneally. The blood collection was carried 24 h before experimental infection and 24 hours after its. The A. hydrophila infection in P. mesopotamicus is characterized by dark skin and clinical signs related to hemorrhage, hypochromic normocytic anemia, decrease on plasmatic proteins and globulins levels, leucopenia, lymphopenia, thrombocytopenia, eosinophilia, neutrophilia and

  16. 嗜麦芽寡养单胞菌临床感染诱因的调查与分析%Stenotrophomonas oligotrophic incentives Aeromonas Clinical Investigation and Analysis of infection

    Institute of Scientific and Technical Information of China (English)

    王景德

    2012-01-01

      Objective Stenotrophomonas oligotrophic incentive Aeromonas infection.Method 23 patients in our hospital unit cel oligotrophic maltophilia respiratory infection cases were retrospectively analyzed and as a group Ⅰ.Replacement of the 23 cases were compared to group Ⅱ.Results In group Ⅰ higher than the rate of use of third generation cephalosporin group Ⅱ, there are significant differences.Conclusion The excessive use of third generation cephalosporin is Stenotrophomonas oligotrophic positive rate of Aeromonas isolated one reason for the increase.%  目的探讨嗜麦芽寡养单胞菌的感染诱因。方法对我院23例嗜麦芽寡养单胞菌感染的呼吸系统的病例进行回顾性分析并以此作为Ⅰ组。另选23例为Ⅱ组进行对照分析。结果Ⅰ组使用三代头孢的比率高于Ⅱ组,有显著性差异。结论过度使用三代头孢是嗜麦芽寡养单胞菌分离阳性率增加的原因之一。

  17. Evaluation of Cross-immune Reaction of Anti-Aeromonas hydrophila AH1 Serum%抗嗜水气单胞菌AH1血清交叉免疫反应的评价

    Institute of Scientific and Technical Information of China (English)

    张丹凤; 陈丽芳; 朱徽

    2010-01-01

    本研究利用嗜水气单胞菌(Aeromonas hydrophila)AH1腹腔注射小白鼠,测定半数致死量LD50为1.35×107.在此基础上制备抗嗜水气单胞菌AH1血清(抗AH1血清),采用凝集反应测出抗AH1血清的效价为25,600.进一步分析抗AH1血清对温和气单胞菌(Aeromonas sobria)等13种致病菌的交叉免疫反应,结果表明,抗AH1血清与气单胞菌属细菌、孤菌属细菌和假单胞属细菌之间的交叉反应程度比较大,而与其它属细菌之间存在的交叉反应程度小,或不存在交叉反应.

  18. Emergence of CTX-M-3, TEM-1 and a new plasmid-mediated MOX-4 AmpC in a multiresistant Aeromonas caviae isolate from a patient with pneumonia.

    Science.gov (United States)

    Ye, Ying; Xu, Xi-Hai; Li, Jia-Bin

    2010-07-01

    Aeromonas species rarely cause pulmonary infection. We report, for what is believed to be the first time, a case of severe pneumonia in a cancer patient caused by Aeromonas caviae. Detailed microbiological investigation revealed that this isolate carried three beta-lactamase-encoding genes (encoding MOX-4, CTX-M-3 and TEM-1) conferring resistance to all beta-lactams but imipenem. The beta-lactamase with a pI of 9.0 was transferred by conjugation and associated with a 7.3 kb plasmid, as demonstrated by Southern blot hybridization. Analysis of the nucleotide and amino acid sequences showed a new ampC gene that was closely related to those encoding the MOX-1, MOX-2 and MOX-3 beta-lactamases. This new plasmid-mediated AmpC beta-lactamase from China was named MOX-4. This is believed to be the first report of MOX-4, CTX-M-3 and TEM-1 beta-lactamases in a multiresistant A. caviae.

  19. 急性白血病患者气单胞菌败血症的临床特征和转归分析%The Clinical Features and Prognosis of Aeromonas Septicaemia in Patients with Acute Leukemia

    Institute of Scientific and Technical Information of China (English)

    李大鹏; 刘庆珍; 苏东; 李增军; 邹德慧

    2013-01-01

      目的加强对急性白血病患者气单胞菌属败血症的认识,为临床估计病情及治疗选择提供依据。方法回顾性总结2002年至2009年发生于我院(位于中国华北地区)血液系统疾患的气单胞菌属败血症患者,分析其流行病学、临床表现、病原微生物学和治疗转归等。结果8年间共16例,均为急性白血病患者。以男性为主,发病季节以夏秋季(5~10月)为主(87.5%)。所有患者均为院内感染,无聚集、流行性发病趋势。菌种包含嗜水气单胞菌和温和气单胞菌,以后者(68.8%)占优势;其中6例(37.5%)伴随其他病原菌败血症,均为温和气单胞菌败血症的患者。所有患者近期或正在接受细胞毒药物化疗,发生败血症时都处于重度中性粒细胞减少。临床表现缺乏特异性,最常见的是寒战、发热(100%),仅有5例(31.3%)患者之前伴随腹泻,4例(25%)并发休克。常见伴发的感染部位包括皮肤软组织感染/蜂窝组织炎(37.5%)、肛周感染(31.3%)、肺感染(25.0%)等。药敏结果对除外青霉素类的绝大多数β内酰胺类抗生素敏感,未见碳青霉烯和氨基糖苷类抗生素耐药。患者均及时接受了敏感抗生素抗感染治疗,病死率仍较高(31.3%)。死亡者发生于起病3~4d内,均为温和气单胞菌同时伴随其他病原菌败血症,多并发休克同时伴随其他部位严重感染如蜂窝组织炎、肺部感染或腹膜炎等。结论气单胞菌败血症虽不常见于北方地区,但多于夏秋季发生于化疗后中性粒细胞减少的急性白血病患者。除青霉素类的β内酰胺类抗生素对绝大多数气单胞菌敏感。温和气单胞菌的致病力更强,应注意复杂感染的预防和早期治疗。%  Objective To specifically recognized the clinical features of Aeromonas septicaemia in the patients with acute leukemia, and to provide a basis

  20. Aeromonas spp. simultaneously harbouring bla(CTX-M-15), bla(SHV-12), bla(PER-1) and bla(FOX-2), in wild-growing Mediterranean mussel (Mytilus galloprovincialis) from Adriatic Sea, Croatia.

    Science.gov (United States)

    Maravić, Ana; Skočibušić, Mirjana; Samanić, Ivica; Fredotović, Zeljana; Cvjetan, Svjetlana; Jutronić, Marinka; Puizina, Jasna

    2013-09-02

    Aeromonas species are becoming renowned as emerging pathogens by increasingly giving rise to a wide spectrum of food and waterborne infections in humans. Another worrisome feature of aeromonads is the growing frequency of antibiotic resistance as a consequence of their prominent diversity in terms of resistance determinants. This study aimed at determining the antimicrobial resistance pattern, prevalence and characterization of acquired β-lactamases, including extended-spectrum-β-lactamases (ESBLs) and AmpC cephalosporinases, as well as the presence of class 1 and 2 integrons, in Aeromonas isolates from wild-growing Mediterranean mussel (Mytilus galloprovincialis) of the eastern coast of Adriatic Sea, Croatia. Isolates were tested for susceptibility to 16 antibiotics and β-lactam/β-lactamase inhibitor combinations. Cephalosporin-resistant isolates were further screened by PCR for genes encoding AmpC (bla(FOX), bla(CMY), bla(MOX), bla(LAT), bla(BIL), bla(DHA), bla(ACC), bla(MIR), bla(ACT)), ESBLs (bla(TEM), bla(SHV), bla(CTX-M), bla(PER), bla(VEB), bla(GES/IBC), bla(OXA)) and integrases (intI1, intI2, intI3). Location of bla genes was characterized by plasmid DNA fingerprinting and Southern blot hybridization. Plasmids carrying ESBL genes were investigated for transferability by conjugation and PCR-based replicon typed. Out of 147 Aeromonas isolates recovered, 30 (20%) demonstrated multiple resistance profile, with co-resistance most frequently detected against penicillins, piperacillin/sulbactam and tetracycline. ESBL-encoding genes were detected in 21 (13 Aeromonas caviae and 8 Aeromonas hydrophila) isolates, with bla(CTX-M-15) gene identified in 19 and bla(SHV-12) in 12 isolates. Among them, 10 isolates simultaneously harboured bla(CTX-M-15) and bla(SHV-12), while 3 isolates additionally carried an AmpC β-lactamase bla(FOX-2) gene. bla(PER-1) gene was identified in a single isolate also harbouring the bla(CTX-M-15) gene. While bla(SHV-12) was chromosomally