1fa7
From Proteopedia
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| , resolution 1.9Å | |||||||
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| Ligands: | |||||||
| Activity: | Lactoylglutathione lyase, with EC number 4.4.1.5 | ||||||
| Related: | 1F9Z, 1FA5, 1FA6, 1FA8, 1fro
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF CD(II)-BOUND GLYOXALASE I OF ESCHERICHIA COLI
Overview
The metalloenzyme glyoxalase I (GlxI) converts the nonenzymatically produced hemimercaptal of cytotoxic methylglyoxal and glutathione to nontoxic S-D-lactoylglutathione. Human GlxI, for which the structure is known, is active in the presence of Zn(2+). Unexpectedly, the Escherichia coli enzyme is inactive in the presence of Zn(2+) and is maximally active with Ni(2+). To understand this difference in metal activation and also to obtain a representative of the bacterial enzymes, the structure of E. coli Ni(2+)-GlxI has been determined. Structures have also been determined for the apo enzyme as well as complexes with Co(2+), Cd(2+), and Zn(2+). It is found that each of the protein-metal complexes that is catalytically active has octahedral geometry. This includes the complexes of the E. coli enzyme with Ni(2+), Co(2+), and Cd(2+), as well as the structures reported for the human Zn(2+) enzyme. Conversely, the complex of the E. coli enzyme with Zn(2+) has trigonal bipyramidal coordination and is inactive. This mode of coordination includes four protein ligands plus a single water molecule. In contrast, the coordination in the active forms of the enzyme includes two water molecules bound to the metal ion, suggesting that this may be a key feature of the catalytic mechanism. A comparison of the human and E. coli enzymes suggests that there are differences between the active sites that might be exploited for therapeutic use.
About this Structure
1FA7 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Determination of the structure of Escherichia coli glyoxalase I suggests a structural basis for differential metal activation., He MM, Clugston SL, Honek JF, Matthews BW, Biochemistry. 2000 Aug 1;39(30):8719-27. PMID:10913283
Page seeded by OCA on Sun Mar 30 20:18:57 2008
