Membrane attack induced by HlyA, a pore-forming toxin of Vibrio cholerae.
Determining the activity of purified toxins has generally provided the basis for establishing their role in the host-pathogen relationship. The bacterial genus Vibrio produces a number of exotoxins in addition to cholera toxin, including haemolysin A (HlyA; Vibrio cholerae) and thermostable direct haemolysin (TDH; Vibrio parahaemolyticus), both of which possess membrane-targeting cytolytic activity. The action of HlyA has been analyzed using protocols previously applied to TDH: lysis and flux experiments on human erythrocytes showed that HlyA similarly causes lysis after cell swelling (by colloid osmosis) due to an elevation of cation permeability. However, kinetic measurements of flux, haemolysis and cation selectivity showed that HlyA and TDH form pores with distinct and characteristic features.
Huntley
J S
JS
University Laboratory of Physiology, Oxford, England, UK.
Sathyamoorthy
V
V
Hall
R H
RH
Hall
A C
AC
D000328:Adult; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D002463:Cell Membrane Permeability; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000187:drug effects* / Q000378:metabolism; D006460:Hemolysin Proteins / Q000737:chemistry / Q000633:toxicity*; D006461:Hemolysis; D006801:Humans; D011188:Potassium / Q000378:metabolism; D012413:Rubidium; D012964:Sodium / Q000378:metabolism; D014734:Vibrio cholerae
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; C084287:hlyA protein, Vibrio cholerae; C068489:thermostable direct hemolysin; D012964:Sodium; D012413:Rubidium; D011188:Potassium