Aeromonas salmonicida

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform

S G B Amyes - One of the best experts on this subject based on the ideXlab platform.

Andrew C. Barnes - One of the best experts on this subject based on the ideXlab platform.

Brian Austin - One of the best experts on this subject based on the ideXlab platform.

  • Aeromonadaceae Representative (Aeromonas salmonicida)
    Bacterial Fish Pathogens, 2012
    Co-Authors: Brian Austin, Dawn A. Austin
    Abstract:

    Aeromonas salmonicida is a significant pathogen of salmonids, and in its atypical form has spread into cyprinids and marine flatfish. Although Aeromonas salmonicida subsp. salmonicida is homogeneous, atypical isolates are more heterogeneous and do not fit into the current subspecies classification. Questions about the ecology of the organism remain but the consensus is that despite earlier work, cells exist in the aquatic environment although largely in a nonculturable form. Diagnostics have moved towards the use of sensitive and specific molecular methods. Disease control has focused on prophylaxis principally by vaccination, probiotics and immunostimulants.

  • Isolation of Aeromonas salmonicida in association with purple‐pigmented bacteria in sediment from a Scottish loch
    Letters in Applied Microbiology, 1998
    Co-Authors: Dawn A. Austin, P. A. W. Robertson, D. K. Wallace, H. Daskalov, Brian Austin
    Abstract:

    Aeromonas salmonicida was recovered in close association with an unidentified purple-pigmented organism, which was isolated from sediment in a Scottish loch during November (1997) and February (1998). However, there has not been any evidence of A. salmonicida infections, specifically furunculosis, associated with the fish in this loch.

  • characterization of atypical Aeromonas salmonicida different methods
    Systematic and Applied Microbiology, 1998
    Co-Authors: Brian Austin, Dawn A. Austin, J.l. Larsen, Bjarnheidur K. Gudmundsdóttir, I Dalsgaard, S Hoie, Jacinta M Thornton, B Ohici, Richard Powell
    Abstract:

    Summary 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. Generally, there was incongruence between the molecular (PCR, RAPD and ribotyping) and phenotypic methods in terms of cluster membership. By PCR, 6 groups were described of which Group 1 encompassed 12 isolates including the type strain of A. salmonicida subsp. smithia . Group 2 accommodated 23 isolates including the reference cultures of subspecies achromogenes and masoucida . The named culture of Haemophilus piscium was recovered in Group 6. By ribotyping and RAPD, the reference cultures were recovered in separate groups. All methods pointed to the uniqueness of subspecies smithia . Most isolates contained 2–6 plasmids, of 2.3 to 150 kb in length. Nevertheless, all isolates possessed certain key characteristics, including Gram-negativity, and the absence of motility.

  • Progress in understanding the fish pathogen Aeromonas salmonicida
    Trends in Biotechnology, 1997
    Co-Authors: Brian Austin
    Abstract:

    Aeromonas salmonicida is the causal agent of furunculosis in various fish species. Detection methods include culturing, serology and molecular biology techniques. Controversy surrounds its possible independent existence in water; enzyme-linked immunosorbent assay and the polymerase chain reaction have detected A. salmonicida in the absence of colony-forming units, but cells that are nonculturable may be significant to fish pathology. Furunculosis is probably transmitted by the pathogen's entry into gills, mouth, anus and/or surface injury of fish through contact with infected fish or contaminated water. Disease-control is possible by good husbandry practices, disease-resistant stock, improved diets, nonspecific immunostimulants, antimicrobial compounds and vaccines.

  • A stable L‐form of the fish pathogen Aeromonas salmonicida
    Letters in Applied Microbiology, 1994
    Co-Authors: A. Gibb, Brian Austin
    Abstract:

    A stable L-form of Aeromonas salmonicida, which resulted from induction with benzylpenicillin, grew on brain heart infusion agar at 0–5°C. The L-form was stored successfully for 10 months in phosphate-buffered saline supplemented with 150 g l-1 glycerol at -70°C. Reversion of the L-form to parental-type walled cells was achieved by transfer to brain heart infusion broth with incubation at 25°C.

T S Hastings - One of the best experts on this subject based on the ideXlab platform.

  • Amoxycillin resistance in Scottish isolates of Aeromonas salmonicida
    Journal of Fish Diseases, 1994
    Co-Authors: Andrew C. Barnes, T S Hastings, S G B Amyes
    Abstract:

    Eighty isolates of Aeromonas salmonicida, recovered from separate outbreaks of furunculosis in famed and wild salmon in Scotland during 1988 and 1989, were examined for susceptibility to the beta-lactam antibiotic amoxycillin. Susceptibility was determined in terms of minimum inhibitory concentration (MIC). All of the A. salmonicida subsp. salmonicida isolates investigated were susceptible to amoxycillin, with MICs of 0.30-1.50 mg l-1. All of the A. salmonicida subsp. achromogenes isolates tested were resistant to amoxycillin, with MICs in excess of 500 mg l-1. The A. salmonicida subsp. achromogenes produced a beta-lactamase enzyme with a pl of approximately 8.0. The enzyme was inducible and its production was unaffected by plasmid curing with ethidium bromide, suggesting that resistance was chromosomal rather than plasmid mediated.

  • Utilization of haem compounds by Aeromonas salmonicida.
    Journal of Fish Diseases, 1994
    Co-Authors: Ian D. Hirst, T S Hastings, Anthony E. Ellis
    Abstract:

    . The ability of A-layer-positi ve (A+) and A-layer-negative (A−) strains of Aeromonas salmonicida to utilize haem sources of iron under conditions of iron-restriction was evaluated. In a plate bioassay, only A+ strains of A. salmonicida were able to utilize haem from a variety of sources including haem, haemin, myoglobin, haemoglobin, haemoglobin- haptoglobin and haem-albumin complexes. Trypsin-digestion of whole cells abolished haem- binding, indicating that binding was cell-surface associated, involving a protein binding site or receptor. Competitive binding studies indicated that all haem compounds were bound by a common receptor, which was not iron-regulated and was associated with the presence of the 49-kDa A-layer protein. The ability of both typical A+ (siderophore-positive) and atypical A+ (siderophore-negative) strains to utilize haem indicated that the mechanism of haem utilization was not siderophore-mediated and that A. salmonicida possesses both siderophore-dependent and siderophore-independent mechanisms to overcome iron-restricted conditions encountered in vivo.

  • in vitro susceptibility of the fish pathogen Aeromonas salmonicida to flumequine
    Antimicrobial Agents and Chemotherapy, 1991
    Co-Authors: Andrew C. Barnes, C S Lewin, T S Hastings, S G B Amyes
    Abstract:

    The activity of the fluoroquinolone flumequine was investigated against the fish pathogen Aeromonas salmonicida and was compared with that of oxolinic acid. Flumequine was more active than oxolinic acid in terms of its MIC against oxolinic acid-resistant isolates of A. salmonicida and was as active as oxolinic acid against susceptible isolates. In contrast to oxolinic acid, flumequine was bactericidal, with only 1% of the bacteria surviving 6 h of exposure to the drug at concentrations slightly above the MIC. Mutation to resistance to flumequine was found to occur at a lower frequency than that to oxolinic acid. Hence, in vitro, flumequine appears to possess some advantages over oxolinic acid against this fish pathogen.

  • InVitro Susceptibility oftheFishPathogen Aeromonas salmonicida toFlumequine
    1991
    Co-Authors: Andrew C. Barnes, C S Lewin, T S Hastings, S G B Amyes
    Abstract:

    Theactivity ofthefluoroquinolone flumequine was investigated against thefish pathogen Aeromonas salmonicida andwas compared withthat ofoxolinic acid. Flumequine was more active thanoxolinic acidin termsofitsMICagainst oxolinic acid-resistant isolates ofA.salmonicida andwas asactive asoxolinic acid against susceptible isolates. Incontrast tooxolinic acid, flumequine was bactericidal, withonly 1% ofthe bacteria surviving 6hofexposuretothedrugatconcentrations slightly above theMIC.Mutation toresistance toflumequine wasfound tooccuratalower frequency thanthat tooxolinic acid. Hence, invitro, flumequine appearstopossesssome advantages overoxolinic acidagainst this fish pathogen.

  • cross resistance between oxytetracycline and oxolinic acid in Aeromonas salmonicida associated with alterations in outer membrane proteins
    Fems Microbiology Letters, 1990
    Co-Authors: Andrew C. Barnes, C S Lewin, T S Hastings, S G B Amyes
    Abstract:

    Oxytetracycline resistant mutants of Aeromonas salmonicida isolated from mutation frequency experiments showed decreased susceptibility to oxolinic acid. Outer membrane preparations of these resistant mutant strains revealed a major protein, with a molecular mass of approximately 37 kDa, which was not present in significant quantities in the parent strain.

Richard Powell - One of the best experts on this subject based on the ideXlab platform.

  • characterization of atypical Aeromonas salmonicida different methods
    Systematic and Applied Microbiology, 1998
    Co-Authors: Brian Austin, Dawn A. Austin, J.l. Larsen, Bjarnheidur K. Gudmundsdóttir, I Dalsgaard, S Hoie, Jacinta M Thornton, B Ohici, Richard Powell
    Abstract:

    Summary 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. Generally, there was incongruence between the molecular (PCR, RAPD and ribotyping) and phenotypic methods in terms of cluster membership. By PCR, 6 groups were described of which Group 1 encompassed 12 isolates including the type strain of A. salmonicida subsp. smithia . Group 2 accommodated 23 isolates including the reference cultures of subspecies achromogenes and masoucida . The named culture of Haemophilus piscium was recovered in Group 6. By ribotyping and RAPD, the reference cultures were recovered in separate groups. All methods pointed to the uniqueness of subspecies smithia . Most isolates contained 2–6 plasmids, of 2.3 to 150 kb in length. Nevertheless, all isolates possessed certain key characteristics, including Gram-negativity, and the absence of motility.

  • dna probe for Aeromonas salmonicida
    Applied and Environmental Microbiology, 1992
    Co-Authors: Maura Hiney, Michael T Dawson, David M Heery, Pete Smith, Frank Gannon, Richard Powell
    Abstract:

    A DNA fragment that is specific to Aeromonas salmonicida has been isolated from a genomic DNA library by differential hybridization. The specificity of this fragment as a DNA probe for A. salmonicida was shown by hybridization against reference strains and clinical isolates of A. salmonicida, related aeromonads, and species from several other bacterial genera. The sensitivity of detection by a polymerase chain reaction test, based on this fragment, was approximately two A. salmonicida cells. Images