3A54

Crystal structure of the A47Q1 mutant of pro-protein-glutaminase

Summary for 3A54

• Entry DOI: 10.2210/pdb3a54/pdb
• Related: 2ZK9 3A55 3A56
• Descriptor: Protein-glutaminase (2 entities in total)
• Functional Keywords: mutant structure like a substrate-enzyme complex, hydrolase
• Biological source: Chryseobacterium proteolyticum
• Total number of polymer chains: 2
• Total formula weight: 67223.50

Authors

Hashizume, R.,Yamaguchi, S.,Mikami, B. (deposition date: 2009-07-30, release date: 2010-08-11, Last modification date: 2024-11-06)

Primary citation

Hashizume, R.,Maki, Y.,Mizutani, K.,Takahashi, N.,Matsubara, H.,Sugita, A.,Sato, K.,Yamaguchi, S.,Mikami, B.
Crystal structures of protein glutaminase and its pro forms converted into enzyme-substrate complex
J.Biol.Chem., 286:38691-38702, 2011

PubMed Abstract: Protein glutaminase, which converts a protein glutamine residue to a glutamate residue, is expected to be useful as a new food-processing enzyme. The crystal structures of the mature and pro forms of the enzyme were refined at 1.15 and 1.73 Å resolution, respectively. The overall structure of the mature enzyme has a weak homology to the core domain of human transglutaminase-2. The catalytic triad (Cys-His-Asp) common to transglutaminases and cysteine proteases is located in the bottom of the active site pocket. The structure of the recombinant pro form shows that a short loop between S2 and S3 in the proregion covers and interacts with the active site of the mature region, mimicking the protein substrate of the enzyme. Ala-47 is located just above the pocket of the active site. Two mutant structures (A47Q-1 and A47Q-2) refined at 1.5 Å resolution were found to correspond to the enzyme-substrate complex and an S-acyl intermediate. Based on these structures, the catalytic mechanism of protein glutaminase is proposed.

PubMed: 21926168
DOI: 10.1074/jbc.M111.255133

Experimental method

X-RAY DIFFRACTION (1.502 Å)