LR White acrylic resin polymerized by microwave energy for immuno-EM ofSaccharomyces cerevisiae: A rapid method

Abstract

Microwave embedment methods have been developed for epoxy and polyester resins. Because the thick yeast cell wall is known to inhibit penetration by many embedding media, we wished to use an embedding agent exhibiting favorable properties of hydrophilicity and low viscosity. The complex requirement for low temperature and curing using UV irradiation with the polymer Lowicryl, and recent advantages described for yeast using LR White, made the latter polymer a good candidate for our studies.Saccharomyces cerevisiaewas grown at 30°C in selective medium to an OD640= 1.0. A modification of the procedure of Tuinen and Riezman was used to fix the cells. Briefly, the cells were washed three times with Sorenson's buffer, pH 7.3, and fixed as a suspension in 3% paraformaldehyde, 0.25% glutaraldehyde in Sorenson's for 2 hours at room temperature. The cells were again washed three times followed by incubation in 1 % sodium meta-periodate at room temperature for one hour.