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Home / Equine Research Bank / Infect Immun / Purification and characterization of a hemolysin produced by...
Infection and immunity1997; 65(5); 1830-1835; doi: 10.1128/iai.65.5.1830-1835.1997

Purification and characterization of a hemolysin produced by Vibrio mimicus.

Abstract: Vibrio mimicus is a causative agent of human gastroenteritis. This pathogen secretes a pore-forming toxin, V. mimicus hemolysin (VMH), which causes hemolysis by three sequential steps: binding to an erythrocyte membrane, formation of a transmembrane pore, and disruption of the cell membrane. VMH with a molecular mass of 63 kDa was purified by ammonium sulfate precipitation and column chromatography with phenyl Sepharose HP and Superose 6 HR. The hemolytic reaction induced by VMH continued up to disruption of all erythrocytes in the assay system. Moreover, VMH that bound preliminarily to erythrocyte ghosts showed a sufficient ability to attack intact erythrocytes. These results suggest reversible binding of the toxin molecule to the membrane. The final cell-disrupting stage was effectively inhibited by various divalent cations. Additionally, some cations, such as Zn2+ and Cu2+, blocked the pore-forming stage at high concentrations. Although VMH could disrupt all kinds of mammalian erythrocytes tested, those from horses were most sensitive to the hemolysin. Horse erythrocytes were found to have the most toxin-binding sites and to be hemolyzed by the least amount of membrane-bound toxin molecules, suggesting that toxin binding to and pore formation on erythrocytes are more effective in horses than in other mammals. Purified VMH induced fluid accumulation in a ligated rabbit ileal loop in a dose-dependent manner. In addition, the antibody against the hemolysin obviously reduced enteropathogenicity of living V. mimicus cells. These findings clearly demonstrate that VMH is probably involved in the virulence of this human pathogen.
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Publication Date: 1997-05-01 PubMed ID: 9125568PubMed Central: PMC175225DOI: 10.1128/iai.65.5.1830-1835.1997Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The study explores the purification and characterization of a toxin, V. mimicus hemolysin (VMH), produced by Vibrio mimicus, a bacterium responsible for gastroenteritis in humans. Key findings include, amongst others, how the VMH binds to red blood cells, forming a pore in the cell membrane that eventually disrupts the cell, and how this process is affected by various cations.

Research Methodology

  • The study began with the purification of V. mimicus hemolysin, a toxin produced by Vibrio mimicus. This involved using ammonium sulfate precipitation and column chromatography with phenyl Sepharose HP and Superose 6 HR.
  • The researchers observed and analyzed the way the toxin affects erythrocytes (red blood cells) in a sequential three-step process: binding to the cell membrane, forming a transmembrane pore, and disrupting the cell membrane.

Results of the Study

  • Results showed that the hemolytic reaction caused by VMH led to the disruption of all red blood cells in the assessed system. Once the toxin binds to these cells, it has the capacity to attack intact erythrocytes, suggesting that the binding of the toxin to the membrane is reversible.
  • The final stage of the cell disruption process was found to be effectively hampered by various divalent cations. Some of these cations, such as Zn2+ and Cu2+, were even able to block the pore-forming stage when administered at high concentrations.
  • The study also compared the response of different types of mammalian red blood cells to the toxin. It was found that horse erythrocytes were most sensitive to the toxin. This was attributed to the fact that the horse erythrocytes had the highest number of toxin-binding sites and required the lowest amount of membrane-bound toxin molecules to cause hemolysis.

Significance of the Study

  • The collected data revealed that the purified VMH toxin could induce fluid accumulation in a ligated rabbit ileal loop depending on the administered dose. This crucial feature implicates VMH in the virulence of the V. mimicus pathogen.
  • Further support for VMH’s role in the virulence of the bacterium was provided by the observed reduction in the enteropathogenicity of V. mimicus cells after the administration of an antibody against the hemolysin toxin.

Overall, this research enhances the understanding of the mechanisms of how V. mimicus causes disease and could potentially aid in the development of treatments against infections caused by this pathogen.

Cite This Article

APA
Miyoshi S, Sasahara K, Akamatsu S, Rahman MM, Katsu T, Tomochika K, Shinoda S. (1997). Purification and characterization of a hemolysin produced by Vibrio mimicus. Infect Immun, 65(5), 1830-1835. https://doi.org/10.1128/iai.65.5.1830-1835.1997

Publication

Infection and immunity
ISSN: 0019-9567
NlmUniqueID: 0246127
Country: United States
Language: English
Volume: 65
Issue: 5
Pages: 1830-1835

Researcher Affiliations

Miyoshi, S
  • Faculty of Pharmaceutical Sciences, Okayama University, Tsushima-Naka, Japan. miyoshi@pheasant.pharm.okayama-u.ac.jp
Sasahara, K
    Akamatsu, S
      Rahman, M M
        Katsu, T
          Tomochika, K
            Shinoda, S

              MeSH Terms

              • Ammonium Sulfate
              • Animals
              • Antibodies, Bacterial / immunology
              • Antibodies, Blocking / immunology
              • Biological Assay
              • Cations, Divalent / pharmacology
              • Chemical Precipitation
              • Chromatography, Agarose
              • Dose-Response Relationship, Drug
              • Electrophoresis, Polyacrylamide Gel
              • Erythrocyte Membrane / drug effects
              • Erythrocytes / drug effects
              • Hemolysin Proteins / immunology
              • Hemolysin Proteins / isolation & purification
              • Hemolysin Proteins / physiology
              • Hemolysis
              • Horses
              • Ileum / drug effects
              • Ileum / pathology
              • In Vitro Techniques
              • Kinetics
              • Rabbits
              • Sheep
              • Vibrio / chemistry
              • Vibrio / immunology
              • Vibrio / pathogenicity

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              This article has been cited 13 times.
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