1ibj
From Proteopedia
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Crystal structure of cystathionine beta-lyase from Arabidopsis thaliana
Overview
The pyridoxal 5'-phosphate-dependent enzyme cystathionine beta-lyase (CBL), catalyzes the penultimate step in the de novo biosynthesis of Met in, microbes and plants. Absence of CBL in higher organisms makes it an, important target for the development of antibiotics and herbicides. The, three-dimensional structure of cystathionine beta-lyase from Arabidopsis, was determined by Patterson search techniques, using the structure of, tobacco (Nicotiana tabacum) cystathionine gamma-synthase as starting, point. At a resolution of 2.3 A, the model was refined to a final, crystallographic R-factor of 24.9%. The overall structure is very similar, to other pyridoxal 5'-phosphate-dependent enzymes of the gamma-family., Exchange of a few critical residues within the active site causes the, different substrate preferences between Escherichia coli and Arabidopsis, CBL. Loss of interactions at the alpha-carboxyl site is the reason for the, poorer substrate binding of Arabidopsis CBL. In addition, the binding, pocket of Arabidopsis CBL is larger than that of E. coli CBL, explaining, the similar binding of L-cystathionine and L-djenkolate in Arabidopsis CBL, in contrast to E. coli CBL, where the substrate binding site is optimized, for the natural substrate cystathionine.
About this Structure
1IBJ is a Single protein structure of sequence from Arabidopsis thaliana with CO3, SO4 and PLP as ligands. Active as Cystathionine beta-lyase, with EC number 4.4.1.8 Full crystallographic information is available from OCA.
Reference
The three-dimensional structure of cystathionine beta-lyase from Arabidopsis and its substrate specificity., Breitinger U, Clausen T, Ehlert S, Huber R, Laber B, Schmidt F, Pohl E, Messerschmidt A, Plant Physiol. 2001 Jun;126(2):631-42. PMID:11402193
Page seeded by OCA on Tue Nov 20 17:14:50 2007
