1r0c: Difference between revisions

[[Image:1r0c.jpg|left|200px]]<br /><applet load="1r0c" size="350" color="white" frame="true" align="right" spinBox="true"  

The structure of aspartate transcarbamylase of Escherichia coli ligated to products (phosphate and N-carbamyl-l-aspartate) has been determined at 2.37 A resolution (R-factor = 0.23, R(free) = 0.27). Results might indicate a product release mode, rather than close analogues to the transition state like those found in our earlier studies of other ligands (N-phosphonacetyl-L-aspartate, carbamyl phosphate plus malonate, phosphonoacetamide plus malonate, or citrate plus phosphate). Ordered product release, first carbamylaspartate (CLA) and then phosphate, might be facilitated by a 4 A movement of phosphate from the substrate-analogue position to the product (phosphate) binding position, and by a somewhat similar release movement of the other product (CLA) relative to its analogue (citrate). This movement is consistent with earlier studies of binding of either pyrophosphate or phosphate alone [Honzatko, R. B., and Lipscomb, W. N. (1982) J. Mol. Biol. 160, 265-286].

1R0C is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=ZN:'>ZN</scene>, <scene name='pdbligand=PO4:'>PO4</scene> and <scene name='pdbligand=NCD:'>NCD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Aspartate_carbamoyltransferase Aspartate carbamoyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.3.2 2.1.3.2] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1R0C OCA].  

[[Category: Lipscomb, W N.]]

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:45:37 2008''