REFINED HIGH-RESOLUTION STRUCTURE OF THE METAL-ION DEPENDENT L-FUCULOSE-1-PHOSPHATE ALDOLASE (CLASS-II) FROM ESCHERICHIA-COLI

Citation
Mk. Dreyer et Ge. Schulz, REFINED HIGH-RESOLUTION STRUCTURE OF THE METAL-ION DEPENDENT L-FUCULOSE-1-PHOSPHATE ALDOLASE (CLASS-II) FROM ESCHERICHIA-COLI, Acta crystallographica. Section D, Biological crystallography, 52, 1996, pp. 1082-1091
Citations number
54
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Crystallography,"Biochemical Research Methods",Biology
ISSN journal
0907-4449
Volume
52
Year of publication
1996
Part
6
Pages
1082 - 1091
Database
ISI
SICI code
0907-4449(1996)52:<1082:RHSOTM>2.0.ZU;2-B
Abstract
The structure of the class II zinc-ion dependent L-fuculose-1-phosphat e aldolase from Escherichia coli in its tetragonal crystal form has be en established at 1.92 Angstrom resolution. The homotetrameric enzyme has a molecular mass of 4 x 24 kDa and follows C-4 symmetry. The struc ture model is exactly symmetrical, which contradicts an observed biref ringence anomaly of the crystals. The four catalytic centers are locat ed in deep clefts at the interfaces of adjacent subunits. The zinc ion is coordinated by three histidines and one glutamate in an almost tet rahedral arrangement. Tn contrast to numerous other catalytically comp etent zinc ions, there is no water molecule in the ligand sphere. Repl acement of zinc by a cobalt ion caused only small structural changes. A search through the Protein Data Bank indicated that the chain fold i s novel. Sequence homology searches revealed a significant similarity to the bacterial L-ribulose-5-phosphate 4-epimerase.