1wq5

Crystal structure of tryptophan synthase alpha-subunit from Escherichia coliCrystal structure of tryptophan synthase alpha-subunit from Escherichia coli

Structural highlights 1wq5 is a 2 chain structure with sequence from "bacillus_coli"_migula_1895 "bacillus coli" migula 1895. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: , Related: 1v7y Activity: Tryptophan synthase, with EC number 4.2.1.20 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT, TOPSAN Function [TRPA_ECOLI] The alpha subunit is responsible for the aldol cleavage of indoleglycerol phosphate to indole and glyceraldehyde 3-phosphate. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed When the tryptophan synthase alpha- and beta(2)-subunits combine to form the alpha(2)beta(2)-complex, the enzymatic activity of each subunit is stimulated by 1-2 orders of magnitude. To elucidate the structural basis of this mutual activation, it is necessary to determine the structures of the alpha- and beta-subunits alone and together with the alpha(2)beta(2)-complex. The crystal structures of the tryptophan synthase alpha(2)beta(2)-complex from Salmonella typhimurium (Stalpha(2)beta(2)-complex) have already been reported. However, the structures of the subunit alone from mesophiles have not yet been determined. The structure of the tryptophan synthase alpha-subunit alone from Escherichia coli (Ecalpha-subunit) was determined by an X-ray crystallographic analysis at 2.3 A, which is the first report on the subunits alone from the mesophiles. The biggest difference between the structures of the Ecalpha-subunit alone and the alpha-subunit in the Stalpha(2)beta(2)-complex (Stalpha-subunit) was as follows. Helix 2' in the Stalpha-subunit, including an active site residue (Asp60), was changed to a flexible loop in the Ecalpha-subunit alone. The conversion of the helix to a loop resulted in the collapse of the correct active site conformation. This region is also an important part for the mutual activation in the Stalpha(2)beta(2)-complex and interaction with the beta-subunit. These results suggest that the formation of helix 2'that is essential for the stimulation of the enzymatic activity of the alpha-subunit is constructed by the induced-fit mode involved in conformational changes upon interaction between the alpha- and beta-subunits. This also confirms the prediction of the conformational changes based on the thermodynamic analysis for the association between the alpha- and beta-subunits. Conformational changes in the alpha-subunit coupled to binding of the beta 2-subunit of tryptophan synthase from Escherichia coli: crystal structure of the tryptophan synthase alpha-subunit alone.,Nishio K, Morimoto Y, Ishizuka M, Ogasahara K, Tsukihara T, Yutani K Biochemistry. 2005 Feb 1;44(4):1184-92. PMID:15667212 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Tryptophan synthase

spinqualitylabelsall models 1wq5, resolution 2.30Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image