1fa8
From Proteopedia
Line 1: | Line 1: | ||
[[Image:1fa8.jpg|left|200px]] | [[Image:1fa8.jpg|left|200px]] | ||
- | + | <!-- | |
- | + | The line below this paragraph, containing "STRUCTURE_1fa8", creates the "Structure Box" on the page. | |
- | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
- | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
- | + | or leave the SCENE parameter empty for the default display. | |
- | | | + | --> |
- | | | + | {{STRUCTURE_1fa8| PDB=1fa8 | SCENE= }} |
- | + | ||
- | + | ||
- | }} | + | |
'''CRYSTAL STRUCTURE OF THE APO FORM GLYOXALASE I OF ESCHERICHIA COLI''' | '''CRYSTAL STRUCTURE OF THE APO FORM GLYOXALASE I OF ESCHERICHIA COLI''' | ||
Line 30: | Line 27: | ||
[[Category: Honek, J F.]] | [[Category: Honek, J F.]] | ||
[[Category: Matthews, B W.]] | [[Category: Matthews, B W.]] | ||
- | [[Category: | + | [[Category: Apo enzyme.]] |
- | [[Category: | + | [[Category: Beta-alpha-beta-beta-beta motif]] |
- | [[Category: | + | [[Category: Homodimer]] |
- | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 16:05:38 2008'' | |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + |
Revision as of 13:05, 2 May 2008
CRYSTAL STRUCTURE OF THE APO FORM 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
1FA8 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 Fri May 2 16:05:38 2008