Amyloid-beta(Abeta42), which is known to be toxic to neuronal cells, protects yeast cells from severe sodium hydroxide toxicity. More than 85% cell death was caused by treatment with 1 mM NaOH and approximately 95% was observed at a 2 mM concentration. However, greater than 55% cells survived the treatment in the presence of Abeta42. A strong protective effect of the peptide was also evident from the differential staining of the treated culture with propidium iodide.