1r0c
From Proteopedia
|
Products in the T State of Aspartate Transcarbamylase: Crystal Structure of the Phosphate and N-carbamyl-L-aspartate Ligated Enzyme
Overview
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].
About this Structure
1R0C is a Protein complex structure of sequences from Escherichia coli with ZN, PO4 and NCD as ligands. Active as Aspartate carbamoyltransferase, with EC number 2.1.3.2 Full crystallographic information is available from OCA.
Reference
Products in the T-state of aspartate transcarbamylase: crystal structure of the phosphate and N-carbamyl-L-aspartate ligated enzyme., Huang J, Lipscomb WN, Biochemistry. 2004 Jun 1;43(21):6422-6. PMID:15157076
Page seeded by OCA on Wed Nov 21 01:09:32 2007
