Sandbox 215
Cholesteryl Ester Transfer Protein is a plasma glycoprotein which is implicated in the transport of cholesteryl esters from the atheroprotective high-density lipoproteins (HDL) to the atherogenic lower-density lipoproteins (LDL). The cristal structure of CETP at 2,2-Å resolution in complex with four bound lipid molecules shows a long tunnel traversing the core of the molecule and has two distinct large openings allowing lipid access. This tunnel is plugged by an amphiphilic phosphatidylcholine at each end.
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| 2obd, resolution 2.10Å () | |||||||||
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| Ligands: | , , , , , , , | ||||||||
| Gene: | CETP (Homo sapiens) | ||||||||
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| Resources: | FirstGlance, OCA, RCSB, PDBsum | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
Role of CETPRole of CETP
StructureStructure
Overall structureOverall structure
CETP is a 476 amino acid residues protein which has an elongated “boomerang shape” with dimensions of 135A° X 30 A°X 35A°. She has a molecular mass of 74 kDa and 28% of this mass is attributed to N-glycosylation at specific residues: 88, 240, 341 and 396. She also has a fold which is homologous to BPI (a protein which is implicated in lipid binding): two similar domains are connected by a linker.
CETP's structure can be divided into four structural units:
- At each end of the protein there is a barrel which is constitued of highly twisted B-sheet and two helices called A and B at the N-terminal and A', B' at C-terminal extremity. Helices B and B' are longer than A and A'
- Between the two barrels there is a central B-sheet which is constitued of six antiparallel strands
- At the C-terminal extremity there is a distorted amphiphathic helix called helix X which is an extension of C-teminal and she interacts with N-terminal residues