1zen
From Proteopedia
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CLASS II FRUCTOSE-1,6-BISPHOSPHATE ALDOLASE
Overview
BACLGROUND: Aldolases catalyze a variety of condensation and cleavage, reactions, with exquisite control on the stereochemistry. These enzymes, therefore, are attractive catalysts for synthetic chemistry. There are two, classes of aldolase: class I aldolases utilize Schiff base formation with, an active-site lysine whilst class II enzymes require a divalent metal, ion, in particular zinc. Fructose-1,6-bisphosphate aldolase (FBP-aldolase), is used in gluconeogenesis and glycolysis; the enzyme controls the, condensation of dihydroxyacetone phosphate with glyceraldehyde-3-phosphate, to yield fructose-1,6-bisphosphate. Structures are available for class I, FBP-aldolases but there is a paucity of detail on the class II enzymes., Characterization is sought to enable a dissection of structure/activity, relationships which may assist the construction of designed aldolases for, use as biocatalysts in synthetic chemistry. RESULTS: The structure of the, dimeric class II FBP-aldolase from Escherichia coli has been determined, using data to 2.5 A resolution. The asymmetric unit is one subunit which, presents a familiar fold, the (alpha/beta)8 barrel. The active centre, at, the C-terminal end of the barrel, contains a novel bimetallic-binding site, with two metal ions 6.2 A apart. One ion, the identity of which is not, certain, is buried and may play a structural or activating role. The other, metal ion is zinc and is positioned at the surface of the barrel to, participate in catalysis. CONCLUSIONS: Comparison of the structure with a, class II fuculose aldolase suggests that these enzymes may share a common, mechanism. Nevertheless, the class II enzymes should be subdivided into, two categories on consideration of subunit size and fold, quaternary, structure and metal-ion binding sites.
About this Structure
1ZEN is a Single protein structure of sequence from Escherichia coli with ZN as ligand. The following page contains interesting information on the relation of 1ZEN with [The Glycolytic Enzymes]. Active as Fructose-bisphosphate aldolase, with EC number 4.1.2.13 Full crystallographic information is available from OCA.
Reference
The crystal structure of a class II fructose-1,6-bisphosphate aldolase shows a novel binuclear metal-binding active site embedded in a familiar fold., Cooper SJ, Leonard GA, McSweeney SM, Thompson AW, Naismith JH, Qamar S, Plater A, Berry A, Hunter WN, Structure. 1996 Nov 15;4(11):1303-15. PMID:8939754
Page seeded by OCA on Sun Nov 18 09:07:42 2007
