Transmembrane protein topology mapping by the substituted cysteine accessibility method (SCAM™):: Application to lipid-specific membrane protein topogenesis

We provide an overview of lipid-dependent polytopic membrane protein topogenesis. with particular emphasis oil Escherichia coli strains genetically altered in their lipid composition and strategies for experimentally determining the transmembrane organization of proteins. A variety of reagents and experimental strategies are described including file use of lipid mutants and thiol-specific chemical reagents to Study lipid-dependent and host-specific membrane protein topogenesis by Substituted cysteine site-directed chemical labeling. Employing strains in which lipid composition can be controlled temporally during membrane protein synthesis and assembly provides a means to observe dynamic changes in protein topology its it function of membrane lipid composition. (c) 2005 Elsevier Inc. All rights reserved.