Structure
Three-dimensional structures of only ~160 different integral membrane proteins are currently determined at atomic resolution by X-ray crystallography or nuclear magnetic resonance spectroscopy due to the difficulties with extraction and crystallization. In addition, structures of many water-soluble domains of IMPs are available in the Protein Data Bank. Their membrane-anchoring α-helices have been removed to facilitate the extraction and crystallization. Search integral membrane proteins in the PDB (based on gene ontology classification)
IMPs can be divided into two groups:
- Integral polytopic proteins (Transmembrane proteins)
- Integral monotopic proteins
Read more about this topic: Integral Membrane Protein
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