The Role of Non-Bonded Interactions in the Conformational Dynamics of Organophosphorous Hydrolase Adsorbed onto Functionalized Mesoporous Silica Surfaces

Journal Article · Thu Jan 14 00:00:00 EST 2010 · Journal of Physical Chemistry B, 114(1):531-540

DOI:https://doi.org/10.1021/jp9083635· OSTI ID:993340

Gomes, Diego Enry B; Lins, Roberto D; Pascutti, Pedro G; Lei, Chenghong; Soares, Thereza A

The enzyme organophosphorous hydrolase (OPH) catalyzes the hydrolysis of a wide variety of organophosphorous compounds with high catalytic efficiency and broad substrate specificity. The immobilization of OPH in functionalized mesoporous silica surfaces increases significantly its catalytic specific activity compared to the enzyme in solution with important applications for the detection and decontamination of insecticides and chemical warfare agents. Experimental measurements of immobilization efficiency as function of the charge and coverage percentage of different functional groups have been interpreted as electrostatic forces being the predominant interactions underlying the adsorption of OPH onto functionalized mesoporous silica surfaces. Explicit solvent molecular dynamics simulations have been performed for OPH in bulk solution and adsorbed onto two distinct interaction potential models of the mesoporous silica functional groups in order to investigate the relative contributions of non-bonded interactions to the conformational dynamics and adsorption of the protein. Our results support the conclusion that while electrostatic interactions are responsible for the specific binding of OPH to the FMS surface, van der Waals forces are detrimental for enhanced interfacial adhesion. Key-words: molecular dynamics simulations; bacterial phosphotriesterase; conformational changes; confined environments; coarse-grain and atomistic models; silanol molecular model.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 993340
• Report Number(s): PNNL-SA-68210; ISSN 1520-5207; 35413; 400412000; TRN: US201023%%286
• Journal Information: Journal of Physical Chemistry B, 114(1):531-540, Vol. 114, Issue 1; ISSN 1520-6106
• Country of Publication: United States
• Language: English

Related Subjects

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
ADHESION
ADSORPTION
CHEMICAL WARFARE AGENTS
CONFORMATIONAL CHANGES
DECONTAMINATION
DETECTION
EFFICIENCY
ELECTROSTATICS
ENZYMES
FUNCTIONALS
HYDROLASES
HYDROLYSIS
INSECTICIDES
MOLECULAR MODELS
SILICA
SOLVENTS
SPECIFICITY
SUBSTRATES
VAN DER WAALS FORCES
Environmental Molecular Sciences Laboratory