Topological mapping methods for α-helical bacterial membrane proteins--an update and a guide

Microbiologyopen. 2013 Apr;2(2):350-64. doi: 10.1002/mbo3.72. Epub 2013 Feb 14.


Integral membrane proteins with α-helical transmembrane segments (TMS) are known to play important and diverse roles in prokaryotic cell physiology. The net hydrophobicity of TMS directly corresponds to the observed difficulties in expressing and purifying these proteins, let alone producing sufficient yields for structural studies using two-/three-dimensional (2D/3D) crystallographic or nuclear magnetic resonance methods. To gain insight into the function of these integral membrane proteins, topological mapping has become an important tool to identify exposed and membrane-embedded protein domains. This approach has led to the discovery of protein tracts of functional importance and to the proposition of novel mechanistic hypotheses. In this review, we synthesize the various methods available for topological mapping of α-helical integral membrane proteins to provide investigators with a comprehensive reference for choosing techniques suited to their particular topological queries and available resources.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Bacterial Proteins / chemistry*
  • Deuterium Exchange Measurement
  • Hydrophobic and Hydrophilic Interactions
  • Mass Spectrometry
  • Membrane Proteins / chemistry
  • Protein Interaction Domains and Motifs
  • Protein Interaction Mapping / methods*
  • Protein Structure, Secondary*


  • Bacterial Proteins
  • Membrane Proteins