View source for 5nuc

[[Image:5nuc.gif|left|200px]]<br /><applet load="5nuc" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="5nuc, resolution 2.1&Aring;" />
'''STAPHYLOCOCCAL NUCLEASE, 1-N-PENTANE THIOL DISULFIDE TO V23C VARIANT'''<br />

==Overview==
The structures of several variants of staphylococcal nuclease with long, flexible unnatural amino acid side chains in the hydrophobic core have, been determined by X-ray crystallography. The unnatural amino acids are, disulfide moieties between the lone cysteine residue in V23C nuclease and, methane, ethane, 1-n-propane, 1-n-butane, 1-n-pentane, and 2-hydroxyethyl, thiols. We have examined changes in the core packing of these mutants., Side chains as large as the 1-n-propyl cysteine disulfide can be, incorporated without perturbation of the structure. This is due, in part, to cavities present in the wild-type protein. The longest side chains are, not well defined, even though they remain buried within the protein, interior. These results suggest that the enthalpy-entropy balance that, governs the rigidity of protein interiors favors tight packing only, weakly. Additionally, the tight packing observed normally in protein, interiors may reflect, in part, the limited numbers of rotamers available, to the natural amino acids.

==About this Structure==
5NUC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus] with CA and THP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Micrococcal_nuclease Micrococcal nuclease], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.31.1 3.1.31.1] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=5NUC OCA]. 

==Reference==
Mobile unnatural amino acid side chains in the core of staphylococcal nuclease., Wynn R, Harkins PC, Richards FM, Fox RO, Protein Sci. 1996 Jun;5(6):1026-31. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=8762134 8762134]
[[Category: Micrococcal nuclease]]
[[Category: Single protein]]
[[Category: Staphylococcus aureus]]
[[Category: Fox, R.O.]]
[[Category: Harkins, P.C.]]
[[Category: Richards, F.M.]]
[[Category: Wynn, R.]]
[[Category: CA]]
[[Category: THP]]
[[Category: endonuclease]]
[[Category: hydrolase]]
[[Category: nuclease]]
[[Category: unnatural amino acid]]

''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 19:38:26 2007''