Bovine seminal ribonuclease destabilizes negatively charged membranes.
Bovine seminal ribonuclease (BS-RNase), an antitumor protein selectively cytotoxic for malignant cells, (i) specifically aggregates negatively charged vesicles and modifies the thermotropic behaviour of the phospholipid; (ii) decreases the amplitude of the thermal transition of the phospholipid; and (iii) provokes lipid-mixing between bilayers of negatively charged vesicles. This engenders leakage of the aqueous vesicle contents. Monomeric BS-RNase, devoid of antitumor action, does not produce these effects. These results suggest that the destabilization of the membrane bilayer promoted by BS-RNase may be involved in the antitumor action of the protein.
Mancheño
J M
JM
Departamento de Bioquímica y Biología Molecular, Facultad de Química, Universidad Complutense, Madrid, Spain.
Gasset
M
M
Oñaderra
M
M
Gavilanes
J G
JG
D'Alessio
G
G
D000818:Animals; D002417:Cattle; D004722:Endoribonucleases / Q000737:chemistry*; D066298:In Vitro Techniques; D008051:Lipid Bilayers / Q000737:chemistry*; D008561:Membrane Fusion; D008563:Membrane Lipids / Q000737:chemistry; D008567:Membranes, Artificial; D012661:Semen / Q000201:enzymology
D008051:Lipid Bilayers; D008563:Membrane Lipids; D008567:Membranes, Artificial; D004722:Endoribonucleases; C032523:ribonuclease SPL