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The structure and function of platelet-activating factor acetylhydrolases

Z S Derewenda¹, U Derewenda

¹Department of Molecular Physiology and Biological Physics, University of Virginia Health Sciences Center, Charlottesville 22906-0011, USA.

Cellular and Molecular Life Sciences : CMLS

|June 30, 1998

Summary

Platelet-activating factor acetylhydrolases (PAF-AHs) are unique enzymes that break down platelet-activating factor (PAF) without needing calcium. Recent studies reveal insights into their structure and function.

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Area of Science:

Biochemistry
Enzymology

Background:

Platelet-activating factor acetylhydrolases (PAF-AHs) are a distinct class of phospholipase A2s.
Unlike other PLA2s, PAF-AHs do not require Ca2+ for activity.
They hydrolyze the sn-2 acyl group of PAF and other phospholipids.

Purpose of the Study:

To elucidate the unique biochemical properties and biological significance of PAF-AHs.
To explore the structure-function relationships of PAF-AHs.

Main Methods:

Biochemical assays to determine enzyme activity and substrate specificity.
Analysis of crystallographic data to understand enzyme structure.

Main Results:

PAF-AHs exhibit unique substrate specificity, targeting PAF and related phospholipids.
Enzyme activity is independent of calcium ions.
Crystallographic studies provide detailed insights into the enzyme's active site and catalytic mechanism.

Conclusions:

PAF-AHs play a crucial role in regulating PAF levels due to their widespread distribution.
Understanding the structure-function relationship is key to their biological roles and potential therapeutic applications.