Dataset Information

Structural Modeling of Wild and Mutant Forms of Human Plasma Platelet Activating Factor-Acetyl Hydrolase Enzyme.

ABSTRACT:

Purpose

To investigate the structural features of wild and mutant forms of the pPAF-AH enzyme that are responsible for coronary artery disease.

Methods

Mutant variants of human pPAF-AH having either V279F, Q281R, or both were modelled and evaluated for stereo chemical and structural correctness. The 3D coordinates of substrate PAF were retrieved from the PubChem database was solvated and minimized on Discovery Studio, and docked to the wild and mutant enzyme models. The top docked pose complex was refined by MD simulation.

Results

pPAF-AH model comprises of 420 amino acids in a ?/?-hydrolase fold that contains a substrate-binding hydrophobic channel with an active site pocket having a catalytic triad of Ser273, Asp296 and His351. Mutations at positions 279 and 281 are opposite one another on the middle of 12 residues long H5 helix that forms the hydrophobic core of the enzyme. V279F causes a tilt on the axis of the mutation bearing helix to avoid steric clashes with the hydrophobic residues on the ?-sheets adjacent to it, inducing subtle conformational changes on the H5-?8 loop, ?8 sheet, and the loop bearing Asp296. A cascade of conformational changes induces a change in the orientation of His351 resulting in loss of hydrogen bonded interaction with catalytic Ser273. Q281R causes a shortening of H5 and ?8, which induces conformational changes of the loops bearing Ser273 and Asp296, respectively. Simultaneous conformational changes of secondary structural elements result in the flipping of His351 causing a break in the catalytic triad. Also, there is a compromise in the substrate-binding area and volume in the mutants resulting in loss of binding to its substrate.

Conclusion

Mutant enzymes show changes at the site of the mutation, secondary motif conformations and global structural conformations that adversely affect the active site, decrease substrate channel volume and decrease stability, thereby affecting enzymatic function.

SUBMITTER: Khan MI

PROVIDER: S-EPMC7751442 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Publications

Structural Modeling of Wild and Mutant Forms of Human Plasma Platelet Activating Factor-Acetyl Hydrolase Enzyme.

Khan Mohd Imran MI Hariprasad Gururao G

Journal of inflammation research 20201216

<h4>Purpose</h4>To investigate the structural features of wild and mutant forms of the pPAF-AH enzyme that are responsible for coronary artery disease.<h4>Methods</h4>Mutant variants of human pPAF-AH having either V279F, Q281R, or both were modelled and evaluated for stereo chemical and structural correctness. The 3D coordinates of substrate PAF were retrieved from the PubChem database was solvated and minimized on Discovery Studio, and docked to the wild and mutant enzyme models. The top docked ...[more]

PMID: 33364808

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Dataset Information

Structural Modeling of Wild and Mutant Forms of Human Plasma Platelet Activating Factor-Acetyl Hydrolase Enzyme.

Purpose

Methods

Results

Conclusion

Publications

Structural Modeling of Wild and Mutant Forms of Human Plasma Platelet Activating Factor-Acetyl Hydrolase Enzyme.

Similar Datasets

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