RT Journal Article
T1 Ion channel activity by Pichia membranifaciens killer toxin
A1 Santos de la Sen, Antonio
A1 Marquina Díaz, Domingo
AB The cytocidal effect of Pichia membranifaciens killer toxin on Candida boidinii cells was studied. The halotolerant yeast P. membranifaciens CYC 1106 produces a unique 18 kDa killer toxin that exerts its killer activity against C. boidinii IGC 3430 only in the presence of NaCl. Metabolic events associated with the loss of C. boidinii IGC 3430 viability were quantitatively identical to those known to occur with K1 killer toxin-treated sensitive strains of Saccharomyces cerevisiae. The death of sensitive cells was characterized by a leakage of potassium, an influx of sodium and a decrease in intracellular pH. These effects occurred prior to and concomitantly with cell death, indicating that they were primary effects of the action of the toxin. Here we report that this protein forms ion-permeable channels in liposome membranes. These channels are freely permeable to common physiological ions. We suggest that channel formation is the cytotoxic mechanism of action of P. membranifaciens killer toxin. The channels described here are sufficiently non-selective to mediate cell death through a discharge of cellular membrane potential and changes in ionic homeostasis. No specific effects against killer toxin-treated sensitive cells were observed when the cell cycle was analysed.
PB John Wiley & Sons
SN 0749-503X
YR 2004
FD 2004
LK https://hdl.handle.net/20.500.14352/107859
UL https://hdl.handle.net/20.500.14352/107859
LA eng
NO Santos, A., y D. Marquina. «Ion Channel Activity by Pichia Membranifaciens Killer Toxin». Yeast, vol. 21, n.o 2, enero de 2004, pp. 151-62. DOI.org (Crossref), https://doi.org/10.1002/yea.1069.
DS Docta Complutense
RD 25 abr 2025