Expression of cloned genes in the yeasts Saccharomyces cerevisiae and Pichia pastoris

Yeast has long been a model organism for biochemical, genetic, and cellular biological studies and is now established as an important system for the expression of cloned genes. The applications of this technology range from basic research into gene function and cellular processes through to industrial-scale manufacture of food products and pharmaceuticals. This article provides practical guidelines for 2 yeast systems that have been widely used, Saccharomyces cerevisiae and Pichia pastoris. It includes methods for laboratory-scale induction of constitutive and inducible promoters as well as simple procedures for optimising expression and for obtaining high yields of protein, for example, for use in structural studies. Common problems that can occur with yeast expression systems are discussed together with possible approaches to solving them. (C) 1996 Wiley-Liss, Inc.