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PubMed · 11959097

Substrate interferes with dimerisation of outer membrane phospholipase A.

Roelie L Kingma·Maarten R Egmond
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Abstract

Outer membrane phospholipase A (OMPLA) activity is regulated by reversible dimerisation with the dimer being the active species. Observed lag phases in activity indicated that dimerisation may be slow relative to turnover. A covalent OMPLA dimer indeed did not display lag phase behaviour. A model for OMPLA kinetics was proposed accounting for a slow dimerisation step. Preincubation conditions determined the initial amount of monomer and influenced both lag times and final activities. Under the conditions used, substrate concentrations higher than 50 mol% inhibited OMPLA activity and increased lag times. Our results may shed more light on mechanisms controlling OMPLA activity in vivo.

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Bacterial Outer Membrane ProteinsCatalysisDimerizationKineticsLysophosphatidylcholinesModels, BiologicalPhospholipases APhospholipases A1Protein Structure, QuaternarySubstrate SpecificityJournal ArticleResearch Support, Non-U.S. Gov't

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Roelie L Kingma, Maarten R Egmond. 2002-04-10. Substrate interferes with dimerisation of outer membrane phospholipase A.. https://doi.org/10.1016/s0014-5793(02)02461-4

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