[en] The crystal structure of the class-B beta-lactamase, BlaB, from the pathogenic bacterium, Chryseobacterium meningosepticum, in complex with the inhibitor, D-captopril, has been solved at 1.5-Angstrom resolution. The enzyme has the typical alphabeta/betaalpha metallo-beta-lactamase fold and the characteristic two metal binding sites of members of the subclass B1, in which two Zn2+ ions were identified. D-Captopril, a diastereoisomer of the commercial drug, captopril, acts as an inhibitor by displacing the catalytic hydroxyl ion required for antibiotic hydrolysis and intercalating its sulfhydryl group between the two Zn2+ ions. Interestingly, D-captopril is located on one side of the active site cleft. The x-ray structure of the complex of the closely related enzyme, IMP-1, with a mercaptocarboxylate inhibitor, which also contains a sulfhydryl group bound to the two Zn2+ ions, shows the ligand to be located on the opposite side of the active site cleft. A molecule generated by fusion of these two inhibitors would cover the entire cleft, suggesting an interesting approach to the design of highly specific inhibitors.
Disciplines :
Biochemistry, biophysics & molecular biology
Author, co-author :
Garcia-Saez, I.
Hopkins, J.
Papamicael, C.
Franceschini, N.
Amicosante, G.
Rossolini, G. M.
Galleni, Moreno ; Université de Liège - ULiège > Département des sciences de la vie > Macromolécules biologiques
Frère, Jean-Marie ; Université de Liège - ULiège > Département des sciences de la vie > Département des sciences de la vie
Dideberg, O.
Language :
English
Title :
The 1.5-angstrom structure of Chryseobacterium meningosepticum zinc beta-lactamase in complex with the inhibitor, D-captopril
Publication date :
27 June 2003
Journal title :
Journal of Biological Chemistry
ISSN :
0021-9258
eISSN :
1083-351X
Publisher :
Amer Soc Biochemistry Molecular Biology Inc, Bethesda, United States - Maryland