Extraction of Proteins from Yeast(S. cerevisiae)by Using a Vibrogen Cell Mill and Low Concentration Alkali and Some Properties of the Protein

Abstract

Effect of sodium hydroxide concentration on the extraction of the proteins from the yeast cell(S. cerevisiae)disintegrated with vibrogen cell mill was examined; 86.3% of the total nitrogen in the cell was extracted with 0.4% NaOH, about 70% of the isolated protein fraction as dry base was proteins and 9.7% was nucleic acid. Asparagine, glutamic acid, alanin, leucine, glycine, and lysine were rich and cystine, methionine and histidine were poor in the amino acid composition of the proteins. The isolated protein fraction has been characterized using an acetic acid-urea polyacrylamide gel electrophoretic system; the fraction consisted of at least 15 protein components, M₁ and M₂ were estimated to have molecular weight of 49, 500 and 36, 500, respectively, on SDS polyacrylamide gel electrophoretical pattern.