Lysing Yeast Cells with Glass Beads for Immunoprecipitation

Yeast cells display cell walls that must first be broken before the addition of detergents for lysis. This method describes the use of glass beads in combination with a mechanical bead beater to disrupt cell walls of both Saccharomyces cerevisiae or Schizosaccharomyces pombe directly in a nonionic detergent Lysis buffer containing 0.1% Nonidet P-40. Alternatively, this protocol can be applied for the lysis of yeast cells in Lysis buffer without detergent; upon completion of the bead beating, Triton X-100 is added to complete lysis. Yeast cells are cultured and collected while in log phase before being washed once and mixed together with glass beads in a tube. The applied shaking process facilitates disruption of the cell walls, upon which separation of yeast and glass beads is accomplished by forcing lysed cells through a hole created in the bottom of the tube during the centrifugation process. An alternative bead-beating protocol details the use of Lysis Buffer 2, which does not contain detergents and calls for the addition of Triton X-100 after cell lysis in the presence of glass beads. Use of Lysis Buffer 2 without detergent may avoid bubble and foam formation during the bead-beating process that could potentially denature proteins.