2spt: Difference between revisions

[[Image:2spt.jpg|left|200px]]<br /><applet load="2spt" size="350" color="white" frame="true" align="right" spinBox="true"  

The structure of Sr-prothrombin fragment 1 has been solved and refined by restrained least-squares methods at 2.5-A resolution to a crystallographic R value of 0.167. The protein structure is very similar to that of Ca-fragment 1. A polymeric array of five Sr2+ ions separated by about 4.0 A is buried among six gamma-carboxyglutamic acid (Gla) residues; three other Sr2+ ions interact with other Gla residues and are located further apart. One of these was not found in the Ca-fragment 1 structure. The coordination of the Sr2+ ions resembles that of Ca2+, but there are some significant differences between them. The most notable is the lack of water coordination with Sr2+ ions and two conformations for Gla 8, which change the coordination of Sr-2 and Sr-3. A hexose moiety of an oligosaccharide was located in the vicinity of Asn101 that was flexibly disordered in Ca-fragment 1. The new Sr2+ ion found may be involved in metal ion phospholipid binding interactions along with Sr-1, and Sr-7, Sr-8.

2SPT is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=NAG:'>NAG</scene> and <scene name='pdbligand=SR:'>SR</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Thrombin Thrombin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.5 3.4.21.5] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2SPT OCA].  

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