Antonie van Leeuwenhoek

, Volume 103, Issue 1, pp 53–67 | Cite as

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

  • Krishnan Sreedharan
  • Rosamma Philip
  • Isaac Sarojani Bright Singh
Original Paper


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 ascFascG), 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 LD50 values of 104.07–105.35 cfu/fish. Furthermore, the organisms could be recovered as pure cultures from the lesions as well as from the internal organs.


Aeromonas veronii Ornamental fishes Phenotypic diversity Virulence potential 



The authors acknowledge The Marine Products Export Development Authority (MPEDA), Ministry of Commerce & Industry, Govt. of India (Project code: 3/3/OFD/HO/2003 dated 25-02-2004), and Department of Biotechnology (DBT), Govt. of India (Project Code: BT/PR4012/AAQ/03/204/2003), for financial support. The first author thanks MPEDA for Fellowship.

Supplementary material

10482_2012_9786_MOESM1_ESM.doc (5 mb)
Supplementary material 1 (DOC 5101 kb)


  1. Abbott SL, Wendy KW, Cheung, Janda JM (2003) The genus Aeromonas: biochemical characteristics, atypical reactions, and phenotypic identification schemes. J Clin Microbiol 41(6):2348–2357PubMedCrossRefGoogle Scholar
  2. Aguilera-Arreola MG, Hernández-Rodriguez C, Zúňiga G, Figueras MJ, Garduňo RA, Castro-Escarpulli G (2007) Virulence potential and genetic diversity of Aeromonas caviae, A. veronii and A. hydrophila clinical isolates from Mexico and Spain: a comparative study. Can J Microbiol 53:877–887PubMedCrossRefGoogle Scholar
  3. Albert MJ, Ansaruzzaman M, Talukder KA, Chopra AK, Rahman KM, Faruque AS, Islam MS, Sack RB, Mollby R (2000) Prevalence of enterotoxin genes in Aeromonas spp. isolated from children with diarrhea, healthy controls, and the environment. J Clin Microbiol 38(10):3785–3790PubMedGoogle Scholar
  4. Alperi A, Martınez-Murcia AJ, Ko WC, Monera A, Saavedra MJ, Figueras MJ (2010) Aeromonas taiwanensis sp. nov. and Aeromonas sanarellii sp. nov., two new clinical species from Taiwan. Int J Syst Evol Microbiol 60:2048–2055PubMedCrossRefGoogle Scholar
  5. Altwegg M, Steigerwalt AG, Altwegg-Bissig R, Luthy-Hottenstein J, Brenner DJ (1990) Biochemical identification of Aeromonas genospecies isolated from humans. J Clin Microbiol 28:258–264PubMedGoogle Scholar
  6. Ando E, Monden K, Mitsuhata R, Kariyama R, Kumon H (2004) Biofilm formation among methicillin-resistant Staphylococcus aureus isolates from patients with urinary tract infection. Acta Med Okayama 58(4):207–214PubMedGoogle Scholar
  7. APHA (1995) Standard Methods for the Examination of Water and Wastewater, 20th edn. American Public Health Association/American Water Works Association/Water Environment Federation, Washington, DCGoogle Scholar
  8. Ballal M, Rajeswari A, Bindu M, Shivananda C (2001) Correlation of the suicide phenomenon in Aeromonas species with virulence and enteropathogenicity. Indian J Pathol Microbiol 44(4):421–425PubMedGoogle Scholar
  9. Barnett TC, Kirov SM, Strom MS, Sanderson K (1997) Aeromonas spp. possesses at least two distinct type IV pilus families. Microb Pathog 23:241–247PubMedCrossRefGoogle Scholar
  10. Bar-Or Y (1990) Hydrophobicity in the aquatic environment. In: Doyle RJ, Rosenberg M (eds) Microbial cell surface hydrophobicity. American Society for Microbiology, Washington, DC, pp 211–228Google Scholar
  11. Bates JM, Mittge E, Kuhlman J, Baden KN, Cheesman SE (2006) Distinct signals from the microbiota promote different aspects of zebrafish gut differentiation. Dev Biol 297:374–386PubMedCrossRefGoogle Scholar
  12. Beaz-Hidalgo R, Alperi R, Buján N, Romalde JL, Figueras MJ (2010) Comparison of phenotypical and genetic identification of Aeromonas strains isolated from diseased fish. Syst Appl Microbiol 33:149–153PubMedCrossRefGoogle Scholar
  13. Boyd JM, Dacanay A, Knickle LC, Touhami A, Brown LL, Jericho MH, Johnson SC, Reith M (2008) Contribution of type IV pili to the virulence of Aeromonas salmonicida subsp. salmonicida in Atlantic salmon (Salmo salar L.). Infect Immun 76:1445–1455PubMedCrossRefGoogle Scholar
  14. Burr SE, Frey J (2007) Analysis of type III effector genes in typical and atypical Aeromonas salmonicida. J Fish Dis 30:711–714PubMedCrossRefGoogle Scholar
  15. Burr SE, Pugovkin D, Wahli T, Segner H, Frey J (2005) Attenuated virulence of an Aeromonas salmonicida subsp. salmonicida type III secretion mutant in a rainbow trout model. Microbiology 151:2111–2118PubMedCrossRefGoogle Scholar
  16. Cai SH, Wu ZH, Jian JC, Lu YS, Tang JF (2012) Characterization of pathogenic Aeromonas veronii bv. veronii associated with ulcerative syndrome from Chinese longsnout catfish (Leiocassis longirostris Günther). Braz. J Microbiol 43(1): doi: 10.1590/S1517-83822012000100046
  17. Carnahan AM, Altwegg M (1996) Taxonomy. In: Austin B, Altwegg M, Gosling PJ, Joseph S (eds) The genus Aeromonas. Wiley, New York, pp 1–38Google Scholar
  18. Chopra AK, Xu XJ, Ribardo D, Gonzalez M, Kuhl K, Petersojn JW, Houston CW (2000) The cytotoxic enterotoxic of Aeromonas hydrophila induces proinflammatory cytokine production and activates arachidonic acid metabolism in macrophages. Infect Immun 68:2808–2818PubMedCrossRefGoogle Scholar
  19. Coquet L, Cosette P, Junter GA, Beucher E, Saiter JM, Jouenne T (2002) Adhesion of Yersinia ruckeri to fish farm materials: influence of cell and material surface properties. Colloids Surf B 26:373–378Google Scholar
  20. Dacanay A, Knickle L, Solanky KS, Boyd JM, Walter JA, Brown LL, Johnson SC, Reith M (2006) Contribution of the type III secretion system (TTSS) to virulence of Aeromonas salmonicida subsp. salmonicida. Microbiology 152:1847–1856PubMedCrossRefGoogle Scholar
  21. Dooley JSG, Trust TJ (1988) Surface protein composition of Aeromonas hydrophila strains virulent for fish: identification of a surface array protein. J Bacteriol 170:499–506PubMedGoogle Scholar
  22. Esteve C, Alcaide E, Canals R, Merino S, Blasco D, Figueras MJ, Tomas JM (2004) Pathogenic Aeromonas hydrophila Serogroup O:14 and O:81 strains with an S layer. Appl Environ Microbiol 70(10):5898–5904PubMedCrossRefGoogle Scholar
  23. Fehr D, Burr SE, Gilbert M, Alayer J, Frey J, Popoff MR (2007) Aeromonas exoenzyme T of Aeromonas salmonicida is a bifunctional protein that targets the host cytoskeleton. J Biol Chem 282(39):28843–28852PubMedCrossRefGoogle Scholar
  24. Figueras MJ, Alperi A, Beaz-Hidalgo R, Stackebrandt E, Brambilla E, Monera A, Martinez-Murcia AJ (2011) Aeromonas rivuli sp. nov., isolated from the upstream region of a karst water rivulet. Int J Syst Evol Microbiol 61:242–248PubMedCrossRefGoogle Scholar
  25. Freeman DJ, Elakliner FR, Keane CT (1989) New method for detecting slime producing by coagulase negative Staphylococci. J Clin Pathol 42:872–874PubMedCrossRefGoogle Scholar
  26. Ghosh P (2004) Process of protein transport by the type III secretion system. Microbiol Mol Biol Rev 68:771–795PubMedCrossRefGoogle Scholar
  27. Golden NJ, Acheson DWK (2002) Identification of motility and auto agglutination Campylobacter jejuni mutants by random transposon mutagenesis. Infect Immun 70(4):1761–1771PubMedCrossRefGoogle Scholar
  28. Goni-Urriza M, Arpin C, Capdepuy M, Dubois V, Caumette P, Quentin C (2002) Type II topoisomerase quinolone resistance-determining regions of Aeromonas caviae, A. hydrophila, and A. sobria complexes and mutations associated with quinolone resistance. Antimicrob Agents Chemother 46:350–359PubMedCrossRefGoogle Scholar
  29. Graf J, Kikuchi Y, Rio RV (2006) Leeches and their microbiota: naturally simple symbiosis models. Trends Microbiol 14:365–371PubMedCrossRefGoogle Scholar
  30. Graham S, Jeffries AH, Secombes CJ (1988) A novel assay to detect macrophage bactericidal activity in fish: factors influencing the killing of Aeromonas salmonicida. J Fish Dis 11:389–396CrossRefGoogle Scholar
  31. Greenman SB, Rutten MJ, Fowler WM, Scheffler L, Shortridge LA, Brown B, Sheppard BC, Deveney KE, Deveney CW, Trunkey DD (1997) Herbicide/pesticide effects on intestinal epithelial growth. Environ Res 75:85–93PubMedCrossRefGoogle Scholar
  32. Han HJ, Taki T, Kondo H, Hirono I, Aoki T (2008) Pathogenic potential of a collagenase gene from Aeromonas veronii. Can J Microbiol 54:1–10PubMedCrossRefGoogle Scholar
  33. Heuzenroeder MW, Wong CYF, Flower RLP (1999) Distribution of two hemolytic toxin genes in clinical and environmental isolates of Aeromonas spp.: correlation with virulence in a suckling mouse model. FEMS Microbiol Lett 174(1):131–136PubMedCrossRefGoogle Scholar
  34. Hossain M (2008) Isolation of pathogenic bacteria from the skin ulcerous symptomatic gourami (Colisa lalia) through 16S rDNA analysis. Univ J Zool Rajshahi Univ 27:21–24Google Scholar
  35. Hulton CSJ, Higgins CF, Sharp PM (1991) ERIC sequences: a novel family of repetitive elements in the genomes of Escherichia coli, Salmonella typhimurium and other enterobacteria. Mol Microbiol 5:825–834PubMedCrossRefGoogle Scholar
  36. Janda JM (1987) Aeromonas and Plesiomonas infections. In: Wentworth BB (ed) Diagnostic procedures for bacterial infection. American Public Health Association, Washington, DC, pp 37–44Google Scholar
  37. Janda JM, Abbott SL (2010) The genus Aeromonas: taxonomy, pathogenicity, and infection. Clin Microbiol Rev 23:35–73PubMedCrossRefGoogle Scholar
  38. Karunasagar I, Karunasagar I, Otta SK (2003) Disease problems affecting fish in tropical environments. J Appl Aquacult 13(3/4):231–249CrossRefGoogle Scholar
  39. Kingombe CIB, Huys G, Tonolla M, Albert MJ, Swings J, Peduzzi R (1999) PCR detection, characterization and distribution of virulence genes in Aeromonas spp. Appl Environ Microbiol 65:5293–5302PubMedGoogle Scholar
  40. Kirov SM, Castrisios M, Shaw JG (2004) Aeromonas flagella (polar and lateral) are enterocyte adhesins that contribute to biofilm formation on surfaces. Infect Immun 72:1939–1945PubMedCrossRefGoogle Scholar
  41. Krovacek K, Faris A, Ahne W, Mansson I (1987) Adhesion of Aeromonas hydrophila and Vibrio anguillarum to fish cells and to mucus coated slides. FEMS Microbiol Lett 42:85–89CrossRefGoogle Scholar
  42. Krzyminska S, Mokracka J, Koczura R, Cwiertnia A, Kaznowski A (2012) Aeromonas spp.-mediated cell-contact cytotoxicity is associated with the presence of type III secretion system. Antonie van Leeuwenhoek 101(2):243–251PubMedCrossRefGoogle Scholar
  43. Lallier R, Daigneault P (1984) Antigenic differentiation of pili from non-virulent fish pathogenic strains of Aeromonas hydrophila. J Fish Dis 7:509–572CrossRefGoogle Scholar
  44. Lavender HF, Jagnow JR, Clegg S (2004) Biofilm formation in vitro and virulence in vivo of mutants of Klebsiella pneumoniae. Infect Immun 72:4888–4890PubMedCrossRefGoogle Scholar
  45. Lee KK, Yii KC (1996) A comparison of three methods for assaying hydrophobicity of pathogenic vibrios. Lett Appl Microbiol 23:343–346CrossRefGoogle Scholar
  46. Lilenbaum W, Nunes ELC, Azeredo MAI (1998) Prevalence and antimicrobial susceptibility of Staphylococci isolated from the skin surface of clinically normal cats. Lett Appl Microbiol 27:224–228PubMedCrossRefGoogle Scholar
  47. Ma Z, Yang H, Li T, Luo L, Gao J (2009) Isolation and identification of pathogenic Aeromonas veronii isolated from infected Siberian sturgeon (Acipenser baerii). Wei Sheng Wu Xue Bao 49(10):1289–1294PubMedGoogle Scholar
  48. Masada CL, LaPatra SE, Morton AW, Strom MS (2002) An Aeromonas salmonicida type IV pilin is required for virulence in rainbow trout Oncorhynchus mykiss. Dis Aqua Organ 15:13–25CrossRefGoogle Scholar
  49. Masignani V, Pizza M, Rappuoli R (2006) Molecular, functional, and evolutionary aspects of ADP ribosylating toxins. In: Alouf JE, Popoff MR (eds) The comprehensive sourcebook of bacterial protein toxins. Elsevier, AmsterdamGoogle Scholar
  50. Mattick JS (2002) Type IV pili and twitching motility. Annu Rev Microbiol 56:289–314PubMedCrossRefGoogle Scholar
  51. Misawa N, Blaser MJ (2000) Detection and characterization of auto agglutination activity by Campylobacter jejuni. Infect Immun 68(11):6168–6175PubMedCrossRefGoogle Scholar
  52. Mittal KR, Lalonde G, Leblanc D, Olivier G, Lallier GR (1980) Aeromonas hydrophila in rainbow trout: relation between virulence and surface characteristics. Can J Microbiol 26:1501–1503PubMedCrossRefGoogle Scholar
  53. Mosmann T (1983) Rapid colorimetric assay for cellular growth and survival, application to proliferation and cytotoxicity assays. J Immun Methods 65:55–63CrossRefGoogle Scholar
  54. Namdari H, Bottone EJ (1988) Correlation of the suicide phenomenon in Aeromonas species with virulence and enteropathogenicity. J Clin Microbiol 26(12):2615–2619PubMedGoogle Scholar
  55. Nerland AH (1996) The nucleotide sequence of the gene encoding GCAT from Aeromonas salmonicida ssp. salmonicida. J Fish Dis 19:145–150CrossRefGoogle Scholar
  56. Ormen O, Ostensvik O (2001) The occurrence of aerolysin-positive Aeromonas spp. and their cytotoxicity in Norwegian water sources. J Appl Microbiol 90:797–802PubMedCrossRefGoogle Scholar
  57. Paniagua C, Rivero O, Anguita J, Naharro G (1990) Pathogenicity factors and virulence for rainbow trout (Salmo gairdneri) of motile Aeromonas sp. isolates from river. J Clin Microbiol 28:350–355PubMedGoogle Scholar
  58. Parker JL, Shaw JG (2011) Aeromonas spp. clinical microbiology and disease. J Infect 62:109–118PubMedCrossRefGoogle Scholar
  59. Paula SJ, Duffey PS, Abbott SL, Kokka RP, Oshiro LS, Janda JM, Shimada T, Sakazaki R (1988) Surface properties of auto agglutinating mesophilic aeromonads. Infect Immun 56:2658–2665PubMedGoogle Scholar
  60. Peeters E, Nelis HJ, Coenye T (2008) Comparison of multiple methods for quantification of microbial biofilms grown in microtitre plates. J Microbiol Methods 72(2):157–165PubMedCrossRefGoogle Scholar
  61. Pemberton JM, Kidd SP, Schmidt R (1997) Secreted enzymes of Aeromonas. FEMS Microbiol Lett 152:1–10PubMedCrossRefGoogle Scholar
  62. Plumb JA, Hanson LH (2010) Health maintenance and principal microbial diseases of cultured fishes, 3rd edn. Wiley, New YorkCrossRefGoogle Scholar
  63. Puthucheary SD, Puah SM, Chua KH (2012) Molecular characterization of clinical isolates of aeromonas species from Malaysia. PLoS ONE 7(2):e30205PubMedCrossRefGoogle Scholar
  64. Rahman M, Navarro CP, Kuhn I, Huys G, Swings J, Mollby R (2002) Identification and characterization of pathogenic Aeromonas veronii biovar sobria associated with epizootic ulcerative syndrome in fish in Bangladesh. Pak J Biol Sci 68(2):650–655Google Scholar
  65. Reddy GSM, Aggarwal RK, Matsumotto GI, Sivaji SI (2000) Arthrobacter flavus sp.nov., a psychrophilic bacterium isolated from a pond in McMurdo dry vally, Antarctica. Int J Syst Evol Microbiol 50:1553–1561PubMedCrossRefGoogle Scholar
  66. Reed MJ, Muench M (1938) A simple method for estimating fifty percent endpoints. Am J Hyg 27:493–497Google Scholar
  67. Rosenberg K, Gutnick D, Rosenberg E (1980) Adherence of bacteria to hydrocarbons, a simple method for measuring cell-surface hydrophobicity. FEMS Microbiol Lett 9:29–33CrossRefGoogle Scholar
  68. Sakai DK (1986) Electrostatic mechanism of survival of virulent Aeromonas salmonicida strains in river water. Appl Environ Microbiol 51:1343–1349PubMedGoogle Scholar
  69. Sambrook J, Russell DW (2001) Molecular cloning: a laboratory manual. Cold Spring Harbor Laboratory Press, New YorkGoogle Scholar
  70. Santos JA, Gonzalez CJ, Otero A, Garcia-Lopez ML (1999) Hemolytic and siderophore production in different Aeromonas species isolated from fish. Appl Environ Microbiol 65:5612–5614PubMedGoogle Scholar
  71. Scoaris DDO, Colacite J, Nakamura CV, Nakamura TU, Filho BAA, Filho BPD (2008) Virulence and antibiotic susceptibility of Aeromonas spp. isolated from drinking water. Antonie van Leeuwenhoek 93:111–122CrossRefGoogle Scholar
  72. Senderovich Y, Ken-Dror S, Vainblat I, Blau D, Izhaki I, Halpern M (2012) A molecular study on the prevalence and virulence potential of aeromonas spp. recovered from patients suffering from diarrhea in Israel. PLoS ONE 7(2):e30070PubMedCrossRefGoogle Scholar
  73. Sha J, Kozlova EV, Chopra AK (2002) Role of various enterotoxins in Aeromonas hydrophila induced gastroenteritis, generation of enterotoxin gene-deficient mutants and evaluation of their enterotoxic activity. Infect Immun 70(4):1924–1935PubMedCrossRefGoogle Scholar
  74. Sha J, Pillae L, Fadl AA, Galindo CL, Erova TE, Chopra AK (2005) The type III secretion system and cytotoxic enterotoxin alter the virulence of Aeromonas hydrophila. Infect Immun 73:6446–6457PubMedCrossRefGoogle Scholar
  75. Shames SR, Finlay BB (2010) Breaking the stereotypes: virulence factor-mediated protection of host cells in bacterial pathogenesis. PLoS Pathog 6:1–3CrossRefGoogle Scholar
  76. Silver AC, Graf J (2009) Prevalence of genes encoding the type three secretion system and the effectors aexT and aexU in the Aeromonas veronii group. DNA Cell Biol 28(8):383–388PubMedCrossRefGoogle Scholar
  77. Silver AC, Williams D, Faucher J, Horneman AJ, Gogarten P, Graf J (2011) Complex evolutionary history of the Aeromonas veronii group revealed by host interaction and DNA sequence data. PLoS ONE 6(2):e1675CrossRefGoogle Scholar
  78. Singh DV, Sanyal SC (1992) Enterotoxicity of clinical and environmental isolates of Aeromonas spp. J Med Microbiol 36(4):269–272PubMedCrossRefGoogle Scholar
  79. Smith P (2006) Breakpoints for disc diffusion susceptibility testing of bacteria associated with fish diseases, a review of current practice. Aquaculture 261(4):1113–1121CrossRefGoogle Scholar
  80. Strauss EJ, Falkow S (1997) Microbial pathogenesis: genomic and beyond. Science 276:707–712PubMedCrossRefGoogle Scholar
  81. Stuber K, Frey J, Burnens AP, Kuhnert P (2003) Detection of type III secretion genes as a general indicator of bacterial virulence. Mol Cell Probes 17:25–32PubMedCrossRefGoogle Scholar
  82. Swift S, Lynch JM, Fish L, Kirke DF, Tomas JM, Stewart GSAB, Williams P (1999) Quarum sensing-dependent regulation and blockade of exoprotease production in Aeromonas hydrophila. Infect Immun 67(10):5192–5199PubMedGoogle Scholar
  83. Tamura K, Nei M (1993) Estimation of the number of nucleotide substitutions in the control region of mitochondrial DNA in humans and chimpanzees. Mol Biol Evol 10:512–526PubMedGoogle Scholar
  84. Tamura K, Peterson D, Peterson N, Stecher G, Nei M, Kumar S (2011) MEGA5: molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Mol Biol Evol 28:2731–2739PubMedCrossRefGoogle Scholar
  85. Tenover FC, Lancaster MV, Hill BC (1988) Characterization of staphylococci with reduced susceptibilities to vancomycin and other glycopeptides. J Clin Microbiol 36:1020–1027Google Scholar
  86. Thompson JD, Higgins DG, Gibson TJ (1994) CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequences weighting, position - specific gap penalties and weight matrix choice. Nucleic Acids Res 22:4673–4680PubMedCrossRefGoogle Scholar
  87. Trower CJ, Abo S, Majeed KN, von Itzstein M (2000) Production of an enterotoxin by a gastro-enteritis-associated Aeromonas strain. J Med Microbiol 49:121–126PubMedGoogle Scholar
  88. van der Marel M, Schroers V, Neuhaus H, Steinhagen D (2008) Chemotaxis towards, adhesion to, and growth in carp gut mucus of two Aeromonas hydrophila strains with different pathogenicity for common carp, Cyprinus carpio L. J Fish Dis 31:321–330PubMedCrossRefGoogle Scholar
  89. Versalovic J, Koeuth T, Lupski JR (1991) Distribution of repetitive DNA sequences in eubacteria and application to fingerprinting of bacterial genomes. Nucleic Acids Res 19:6823–6831PubMedCrossRefGoogle Scholar
  90. Von Gravenitz A (2007) The role of Aeromonas in diarrhea: a review. Infection 35:59–64CrossRefGoogle Scholar
  91. Wang G, Clark CG, Liu C, Pucknell C, Munro CK, Kruk TMAC, Caldeira R, Woodward DL, Rodgers FG (2003) Detection and characterization of the hemolysin genes in Aeromonas hydrophila and Aeromonas sobria by multiplex PCR. J Clin Microbiol 41(3):31048–31054CrossRefGoogle Scholar
  92. Wong CY, Heuzenroeder MW, Flower RL (1998) Inactivation of two haemolytic toxin genes in Aeromonas hydrophila attenuates virulence in a suckling mouse model. Microbiology 144:291–298PubMedCrossRefGoogle Scholar
  93. Wu CJ, Wu JJ, Yan JJ, Lee HC, Lee NY, Chang CM, Shih HI, Wu HM, Wang LR, Ko WC (2007) Clinical significance and distribution of putative virulence markers of 116 consecutive clinical Aeromonas isolates in southern Taiwan. J Infect 54:151–158PubMedCrossRefGoogle Scholar
  94. Xia X, Xie Z (2001) DAMBE: software package for data analysis in molecular biology and evolution. J Hered 92:371–373PubMedCrossRefGoogle Scholar
  95. Yamamoto S, Kasai H, Arnold DL, Jackson RW, Vivian A, Harayama S (2000) Phylogeny of the genus Pseudomonas: intrageneric structure reconstructed from the nucleotide sequences of gyrB and rpoD genes. Microbiology 146:2385–2394PubMedGoogle Scholar
  96. Yanez MA, Catalan V, Apraiz D, Figueras MJ, Martınez-Murcia AJ (2003) Phylogenetic analysis of members of the genus Aeromonas based on gyrB gene sequences. Int J Syst Evol Microbiol 53:875–883PubMedCrossRefGoogle Scholar
  97. Yesmin S, Rahman MH, Hussain AM, Khan AR, Pervin F, Hossain MA (2004) Aeromonas hydrophila infection in fish of swamps in Bangladesh. Pak J Biol Sci 7(3):409–411CrossRefGoogle Scholar
  98. Yucel N, Erdem B, Kaya D (2005) Some virulence properties and characterization of motile Aeromonas species from milk and white cheese. Int J Dairy Technol 58(2):106–110CrossRefGoogle Scholar
  99. Zmantar T, Kouidhi B, Miladi H, Mahdouani K, Bakhrouf A (2010) A Microtiter plate assay for Staphylococcus aureus biofilm quantification at various pH levels and hydrogen peroxide supplementation. New Microbiol 33:137–145PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Krishnan Sreedharan
    • 1
  • Rosamma Philip
    • 2
  • Isaac Sarojani Bright Singh
    • 1
  1. 1.National Centre for Aquatic Animal HealthCochin University of Science and TechnologyCochinIndia
  2. 2.Department of Marine Biology, Microbiology and Biochemistry, School of Marine SciencesCochin University of Science and TechnologyCochinIndia

Personalised recommendations