4ZM7

PcCel45A N105D mutatnt at cryo condition

Summary for 4ZM7

• Entry DOI: 10.2210/pdb4zm7/pdb
• Related: 3X2G 3X2H 3X2I 3X2J 3X2K 3X2M
• Descriptor: Endoglucanase V-like protein (2 entities in total)
• Functional Keywords: cellulase endo-glucanase, hydrolase
• Biological source: Phanerochaete chrysosporium (White-rot fungus)
• Total number of polymer chains: 1
• Total formula weight: 18179.78

Authors

Nakamura, A.,Ishida, T.,Samejima, M.,Igarashi, K. (deposition date: 2015-05-02, release date: 2015-09-02, Last modification date: 2024-11-13)

Primary citation

Nakamura, A.,Ishida, T.,Kusaka, K.,Yamada, T.,Fushinobu, S.,Tanaka, I.,Kaneko, S.,Ohta, K.,Tanaka, H.,Inaka, K.,Higuchi, Y.,Niimura, N.,Samejima, M.,Igarashi, K.
"Newton's cradle" proton relay with amide-imidic acid tautomerization in inverting cellulase visualized by neutron crystallography.
Sci Adv, 1:e1500263-e1500263, 2015

PubMed Abstract: Hydrolysis of carbohydrates is a major bioreaction in nature, catalyzed by glycoside hydrolases (GHs). We used neutron diffraction and high-resolution x-ray diffraction analyses to investigate the hydrogen bond network in inverting cellulase PcCel45A, which is an endoglucanase belonging to subfamily C of GH family 45, isolated from the basidiomycete Phanerochaete chrysosporium. Examination of the enzyme and enzyme-ligand structures indicates a key role of multiple tautomerizations of asparagine residues and peptide bonds, which are finally connected to the other catalytic residue via typical side-chain hydrogen bonds, in forming the "Newton's cradle"-like proton relay pathway of the catalytic cycle. Amide-imidic acid tautomerization of asparagine has not been taken into account in recent molecular dynamics simulations of not only cellulases but also general enzyme catalysis, and it may be necessary to reconsider our interpretation of many enzymatic reactions.

PubMed: 26601228
DOI: 10.1126/sciadv.1500263

Experimental method

X-RAY DIFFRACTION (0.701 Å)