Sandbox Reserved 1121: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 5: | Line 5: | ||
You may include any references to papers as in: the use of JSmol in Proteopedia <ref>DOI 10.1002/ijch.201300024</ref> or to the article describing Jmol <ref>PMID:21638687</ref> to the rescue. | You may include any references to papers as in: the use of JSmol in Proteopedia <ref>DOI 10.1002/ijch.201300024</ref> or to the article describing Jmol <ref>PMID:21638687</ref> to the rescue. | ||
The C-reactive protein has been given this name because it precipitates the C polysaccharide in the cell wall.<ref name="kumar"/> | The C-reactive protein has been given this name because it precipitates the C polysaccharide in the cell wall.<ref name="kumar">Kumar, S. V., Ravunny, R. K., Chakraborty, C. (2011), Conserved Domains, Conserved Residues, and Surface Cavities of C-reactive Protein (CRP), Appl Biochem Biotechnol, 165:497–505</ref> | ||
== Structure == | == Structure == | ||
| Line 12: | Line 12: | ||
The C-reactive protein is a homopentamer of non-covalently bound subunits. Each subunit is a 25 Da protein consisting of 224 residues bound together. The secondary structure is formed of four α-helices and three β-sheets (five-stranded, three-stranded and seven-stranded).<ref>http://www.uniprot.org/uniprot/P02741</ref> The predominant structure is β-sheet <ref>http://www.unco.edu/nhs/Chemistry/faculty/dong/pub/pentraxin.pdf</ref> but short helical regions can be notice for residues 43 and 185.<ref name="kumar"/> Residues Glu197 and Lys123 in CRP form an intermolecular ion pair.<ref name="thompson" /> | The C-reactive protein is a homopentamer of non-covalently bound subunits. Each subunit is a 25 Da protein consisting of 224 residues bound together. The secondary structure is formed of four α-helices and three β-sheets (five-stranded, three-stranded and seven-stranded).<ref>http://www.uniprot.org/uniprot/P02741</ref> The predominant structure is β-sheet <ref>http://www.unco.edu/nhs/Chemistry/faculty/dong/pub/pentraxin.pdf</ref> but short helical regions can be notice for residues 43 and 185.<ref name="kumar"/> Residues Glu197 and Lys123 in CRP form an intermolecular ion pair.<ref name="thompson" /> | ||
=== Calcium binding-site === | === Calcium binding-site === | ||
<ref name=" | CRP is a calcium dependent strcuture. Effectively, Ca2+ is required for PC binding, and more precisely for the formation of the PCbinding site. Structural rearrangements of the CRP occur when the protein binds calcium. The protection against denaturation and proteolysis. <ref name="ramadan">Ramadan, M. A. M., Shrive, A. K., Holden, D., Myles, D. A. A., Volanakis, J. E., Larry J.DeLucas, L. J., Greenhough, T. J. (2002), The three-dimensional structure of calcium-depleted human C-reactive protein from perfectly twinned crystals, Acta Cryst., D58 :992-1001</ref> | ||
=== PC binding site === | === PC binding site === | ||
PC stands for phosphocoline. It is a phospholipid in cell membranes and a plasma lipoproteins.<ref name="thompson">Thompson, D., Pepys, M. B., Wood, S. P. (1999), The physiological structure of human C-reactive protein and its complex with phosphocholine, Structure February 1999, 7:169–177.</ref> Phe-66 and Glu-81 are the two key residues that enable the binding of PC. <ref name="kumar"/> | PC stands for phosphocoline. It is a phospholipid in cell membranes and a plasma lipoproteins.<ref name="thompson">Thompson, D., Pepys, M. B., Wood, S. P. (1999), The physiological structure of human C-reactive protein and its complex with phosphocholine, Structure February 1999, 7:169–177.</ref> Phe-66 and Glu-81 are the two key residues that enable the binding of PC. <ref name="kumar"/> | ||
