Mapping of Membrane Protein Topology by Substituted Cysteine Accessibility Method (SCAM™)

  • Mikhail Bogdanov
Part of the Methods in Molecular Biology book series (MIMB, volume 1615)


A described simple and advanced protocol for the substituted-cysteine accessibility method as applied to transmembrane (TM) orientation (SCAM™) permits a topology analysis of proteins in their native state and can be universally adapted to any membrane system to either systematically map an uniform topology or identify and quantify the degree of mixed topology. In this approach, noncritical individual amino acids that are thought to reside in the putative extracellular or intracellular loops of a membrane protein are replaced one at a time by cysteine residue, and the orientation with respect to the membrane is evaluated using a pair of membrane-impermeable nondetectable and detectable thiol-reactive labeling reagents.

Key words

Membrane protein Topology Cysteine Maleimides SCAM™ 


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Copyright information

© Springer Science+Business Media LLC 2017

Authors and Affiliations

  1. 1.Department of Biochemistry & Molecular BiologyUniversity of Texas Health Science Center at Houston, McGovern Medical SchoolHoustonUSA

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