6O69

Crystal Structure of Double Mutant L380R/F535K of Human Acetylcholinesterase

Summary for 6O69

• Entry DOI: 10.2210/pdb6o69/pdb
• Descriptor: Acetylcholinesterase, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-[alpha-L-fucopyranose-(1-6)]2-acetamido-2-deoxy-beta-D-glucopyranose (3 entities in total)
• Functional Keywords: hydrolase
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 60043.69

Authors

Bester, S.M.,Height, J.J.,Pegan, S.D. (deposition date: 2019-03-05, release date: 2019-05-01, Last modification date: 2024-10-23)

Primary citation

Bester, S.M.,Adipietro, K.A.,Funk, V.L.,Myslinski, J.M.,Keul, N.D.,Cheung, J.,Wilder, P.T.,Wood, Z.A.,Weber, D.J.,Height, J.J.,Pegan, S.D.
The structural and biochemical impacts of monomerizing human acetylcholinesterase.
Protein Sci., 28:1106-1114, 2019

PubMed Abstract: Serving a critical role in neurotransmission, human acetylcholinesterase (hAChE) is the target of organophosphate nerve agents. Hence, there is an active interest in studying the mechanism of inhibition and recovery of enzymatic activity, which could lead to better countermeasures against nerve agents. As hAChE is found in different oligomeric assemblies, certain approaches to studying it have been problematic. Herein, we examine the biochemical and structural impact of monomerizing hAChE by using two mutations: L380R/F535K. The activities of monomeric hAChE L380R/F535K and dimeric hAChE were determined to be comparable utilizing a modified Ellman's assay. To investigate the influence of subunit-subunit interactions on the structure of hAChE, a 2.1 Å X-ray crystallographic structure was determined. Apart from minor shifts along the dimer interface, the overall structure of the hAChE L380R/F535K mutant is similar to that of dimeric hAChE. To probe whether the plasticity of the active site was overtly impacted by monomerizing hAChE, the kinetic constants of (P ) - VX (ethyl({2-[bis(propan-2-yl)amino]ethyl}sulfanyl)(methyl)phosphinate) inhibition and subsequent rescue of hAChE L380R/F535K activity with HI-6 (1-(2'-hydroxyiminomethyl-1'-pyridinium)-3-(4'-carbamoyl-1-pyridinium)) were determined and found to be comparable to those of dimeric hAChE. Thus, hAChE L380R/F535K could be used as a substitute for dimeric hAChE when experimentally probing the ability of the hAChE active site to accommodate future nerve agent threats or judge the ability of new therapeutics to access the active site.

PubMed: 30993792
DOI: 10.1002/pro.3625

Experimental method

X-RAY DIFFRACTION (2.081 Å)