The crystal structure of glutamyl endopeptidase from Bacillus intermedius reveals a structural link between zymogen activation and charge compensation.
Extracellular glutamyl endopeptidase from Bacillus intermedius (BIEP) is a chymotrypsin-like serine protease which cleaves the peptide bond on the carboxyl side of glutamic acid. Its three-dimensional structure was determined for C222(1) and C2 crystal forms of BIEP to 1.5 and 1.75 A resolution, respectively. The topology of BIEP diverges from the most common chymotrypsin architecture, because one of the domains consists of a beta-sandwich consisting of two antiparallel beta-sheets and two helices. In the C2 crystals, a 2-methyl-2,4-pentanediol (MPD) molecule was found in the substrate binding site, mimicking a glutamic acid. This enabled the identification of the residues involved in the substrate recognition. The presence of the MPD molecule causes a change in the active site; the interaction between two catalytic residues (His47 and Ser171) is disrupted. The N-terminal end of the enzyme is involved in the formation of the substrate binding pocket. This indicates a direct relation between zymogen activation and substrate charge compensation.
European Molecular Biology Laboratory, c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany.
Rob
R
Meijers
Elena V
EV
Blagova
Vladimir M
VM
Levdikov
Galina N
GN
Rudenskaya
Galina G
GG
Chestukhina
Tatiana V
TV
Akimkina
Sergei V
SV
Kostrov
Victor S
VS
Lamzin
Inna P
IP
Kuranova
D000595:Amino Acid Sequence; D000838:Anions / Q000737:chemistry; D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D001665:Binding Sites; D020134:Catalytic Domain; D003460:Crystallization; D018360:Crystallography, X-Ray; D004220:Disulfides / Q000737:chemistry; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000737:chemistry* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D011485:Protein Binding; D017510:Protein Folding; D012697:Serine Endopeptidases / Q000737:chemistry* / Q000302:isolation & purification; D013210:Staphylococcus / Q000201:enzymology; D055672:Static Electricity; D013302:Streptomyces / Q000201:enzymology; D040681:Structural Homology, Protein; D013379:Substrate Specificity
D000838:Anions; D001426:Bacterial Proteins; D004220:Disulfides; D004792:Enzyme Precursors; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase