NMR structures of phospholipase A2 reveal conformational changes during interfacial activation.

B van den Berg; M Tessari; R Boelens; R Dijkman; G H de Haas; R Kaptein; H M Verheij

doi:10.1038/nsb0595-402

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NMR structures of phospholipase A2 reveal conformational changes during interfacial activation.

B van den Berg·M Tessari·R Boelens·R Dijkman·G H de Haas·R Kaptein·H M Verheij

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Abstract

It has long been proposed that the higher activity of phospholipase A2 (PLA2) for substrates presented as multimolecular aggregates compared to dispersed molecules (interfacial activation) arises due to a conformational change in the enzyme. X-ray studies have, however, failed to identify any such change. Here we report the solution structures of porcine pancreatic PLA2 both free and as a ternary complex with micelles and a competitive inhibitor. Important differences between these structures indicate that conformational changes may play an important role in the mechanism of interfacial activation in PLA2s.

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Amino Acid Sequence Animals Binding, Competitive Enzyme Activation Lipids Magnetic Resonance Spectroscopy Micelles Molecular Sequence Data Molecular Structure Phospholipases A Phospholipases A2 Phospholipids Phosphorylcholine Protein Conformation Swine Water Journal Article

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B van den Berg, M Tessari, R Boelens, R Dijkman, G H de Haas, R Kaptein, H M Verheij. 1995. NMR structures of phospholipase A2 reveal conformational changes during interfacial activation.. https://doi.org/10.1038/nsb0595-402

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