1-Butaneboronic acid binding to Aeromonas proteolytica aminopeptidase: a case of arrested development.
Hydrolases containing two metal ions connected by a bridging ligand catalyze reactions important in carcinogensis, tissue repair, post-translational modification, control and regulation of biochemical pathways, and protein degradation. The aminopeptidase from Aeromonas proteolytica serves as a paradigm for the study of such bridged bimetallic proteases since its three-dimensional structure is known to very high resolution and its catalytic reaction is amenable to spectroscopic examination. Herein, we report the X-ray crystal structure at 1.9 A resolution of AAP complexed with 1-butaneboronic acid (BuBA). This structure suggests that this complex represents a snapshot of the proteolytic reaction in an arrested form between the Michaelis complex and the transition state. Comparison of the structure with spectroscopic and other data allows us to conclude that the apparently structurally symmetrical dizinc site is actually asymmetric electrostatically.
The Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts 02454, USA.
C C
CC
De Paola
B
B
Bennett
R C
RC
Holz
D
D
Ringe
G A
GA
Petsko
D000333:Aeromonas / Q000201:enzymology*; D000626:Aminopeptidases / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D001896:Boron Compounds / Q000737:chemistry* / Q000378:metabolism; D002384:Catalysis; D002417:Cattle; D003460:Crystallization; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000378:metabolism; D006868:Hydrolysis; D007908:Lens, Crystalline / Q000201:enzymology; D007931:Leucyl Aminopeptidase / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D011487:Protein Conformation; D013053:Spectrophotometry; D013379:Substrate Specificity; D015032:Zinc / Q000737:chemistry
D001896:Boron Compounds; D004791:Enzyme Inhibitors; C030433:n-butylboronic acid; D000626:Aminopeptidases; D007931:Leucyl Aminopeptidase; D015032:Zinc