Sandbox207: Difference between revisions
From Proteopedia
Jump to navigationJump to search
Elise Rosati (talk | contribs) No edit summary |
Elise Rosati (talk | contribs) No edit summary |
||
| Line 12: | Line 12: | ||
==Structure== | ==Structure== | ||
=== | ===Gene structure, family=== | ||
:The CRP gene is located on chromosome 1q23. It is composed of two exons and one intron. This gene is regulated by interleukin-6, the principal inducer of the gene during the acute phase. CRP is secreted by hepatocytes. | :The CRP gene is located on chromosome 1q23. It is composed of two exons and one intron. This gene is regulated by interleukin-6, the principal inducer of the gene during the acute phase. CRP is secreted by hepatocytes. | ||
| Line 26: | Line 26: | ||
:There are interpromoter interactions between the subunits: three salt bridges are included and the 115-123 loop of one protomer and the 40-42 and 197-202 regions of adjacent protomers are involved. Moreover, the subunits are capable to rotate by 15-20° around an axis parallel to the central alpha-helix. | :There are interpromoter interactions between the subunits: three salt bridges are included and the 115-123 loop of one protomer and the 40-42 and 197-202 regions of adjacent protomers are involved. Moreover, the subunits are capable to rotate by 15-20° around an axis parallel to the central alpha-helix. | ||
: Thanks to this rotation, the alpha-helices can lie closer to the axis of the pentamere, therefore bringin the bound Ca2+ further away from it. On each subunit, we can find phosphocholine bound in a shallow surface pocket. With the help of phosphate groups and Glu81 via the choline moiety, the phosphocholine can interact with the two protein-bound ions. | : Thanks to this rotation, the alpha-helices can lie closer to the axis of the pentamere, therefore bringin the bound Ca2+ further away from it. On each subunit, we can find phosphocholine bound in a shallow surface pocket. With the help of phosphate groups and Glu81 via the choline moiety, the phosphocholine can interact with the two protein-bound ions. | ||
http://biology.kenyon.edu/BMB/Chime2/2005/Jenny/FRAMES/ | |||
Revision as of 16:06, 26 December 2011
This page is reserveted for a work from two students in ESBS (A.Butet and E.Rosati) Thanks.
| |||||||||||||
| 1gnh, resolution 3.00Å (default scene) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ligands: | CA | ||||||||||||
| |||||||||||||
| |||||||||||||
| |||||||||||||
| Resources: | FirstGlance, OCA, RCSB, PDBsum | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
C-reactive protein, CRP
Structure
Gene structure, family
- The CRP gene is located on chromosome 1q23. It is composed of two exons and one intron. This gene is regulated by interleukin-6, the principal inducer of the gene during the acute phase. CRP is secreted by hepatocytes.
- The Human CRP belongs to the pentraxin family of proteins having five identical, non-covalently associated subunits that form a symmetrical homopentameric ring. The pentraxin family is highly conserved in evolution.
Size
- Each subunit contains 206 amino acid residues (approximately 23kDa) and is non-glycosylated. The outside diameter of the pentamer is 102 Å, the diameter of the inner core is 30 Å, and the diameter of the protomer is 36 Å.
Detailed strucutre
- Each promoter consists of two anti-parallel β sheets (the lectin fold) with an α helix on the effector face of the protein. The ligand biding site is located on the concave face of the protein, and is composed of loops with 2 calcium ions bound 4 Å apart by protein side-chains.
- The recognition face contains the which consists of two coordinated calcium ions next to a hydrophobic pocket in which the phosphocholine stays.
- There are interpromoter interactions between the subunits: three salt bridges are included and the 115-123 loop of one protomer and the 40-42 and 197-202 regions of adjacent protomers are involved. Moreover, the subunits are capable to rotate by 15-20° around an axis parallel to the central alpha-helix.
- Thanks to this rotation, the alpha-helices can lie closer to the axis of the pentamere, therefore bringin the bound Ca2+ further away from it. On each subunit, we can find phosphocholine bound in a shallow surface pocket. With the help of phosphate groups and Glu81 via the choline moiety, the phosphocholine can interact with the two protein-bound ions.
