Phospholipid hydrolysis caused by Clostridium perfringens α-toxin facilitates the targeting of perfringolysin O to membrane bilayers.
Clostridium perfringens causes gas gangrene and gastrointestinal disease in humans. These pathologies are mediated by potent extracellular protein toxins, particularly α-toxin and perfringolysin O (PFO). While α-toxin hydrolyzes phosphatidylcholine and sphingomyelin, PFO forms large transmembrane pores on cholesterol-containing membranes. It has been suggested that the ability of PFO to perforate the membrane of target cells is dictated by how much free cholesterol molecules are present. Given that C. perfringens α-toxin cleaves the phosphocholine headgroup of phosphatidylcholine, we reasoned that α-toxin may increase the number of free cholesterol molecules in the membrane. Our present studies reveal that α-toxin action on membrane bilayers facilitates the PFO−cholesterol interaction as evidenced by a reduction in the amount of cholesterol required in the membrane for PFO binding and pore formation. These studies suggest a mechanism for the concerted action of α-toxin and PFO during C. perfringens pathogenesis.
Moe
Paul C
PC
Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, USA.
Heuck
Alejandro P
AP
D001426:Bacterial Proteins / Q000378:metabolism*; D001427:Bacterial Toxins / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002784:Cholesterol / Q000378:metabolism; D003016:Clostridium perfringens / Q000378:metabolism / Q000502:physiology*; D005738:Gas Gangrene / Q000382:microbiology*; D006460:Hemolysin Proteins / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D006801:Humans; D006868:Hydrolysis; D008081:Liposomes / Q000378:metabolism; D008958:Models, Molecular; D010743:Phospholipids / Q000378:metabolism*; D011485:Protein Binding; D010738:Type C Phospholipases / Q000378:metabolism*
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D002135:Calcium-Binding Proteins; D006460:Hemolysin Proteins; D008081:Liposomes; D010743:Phospholipids; C020452:Clostridium perfringens theta-toxin; D002784:Cholesterol; D010738:Type C Phospholipases; C040649:alpha toxin, Clostridium perfringens