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PubMed · 10601702

An active-site titration method for lipases.

D Rotticci·T Norin·K Hult·M Martinelle
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Abstract

A method for active-site titration of lipases has been developed based on irreversible inhibition by methyl p-nitrophenyl n-hexylphosphonate. This method was applied to five lipases displaying from minor to pronounced interfacial activation. Soluble and immobilized lipases were successfully titrated in aqueous media. A low concentration of sodium dodecyl sulfate was needed for lipases displaying pronounced interfacial activation. The carrier of some of the immobilized preparations adsorbed part of the produced p-nitrophenolate. This problem could be solved by extracting the p-nitrophenolate after inhibition. The method was extended to apolar organic solvents in the case of immobilized lipase preparations.

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Binding SitesEnzyme InhibitorsEnzymes, ImmobilizedHeptanesLipaseSerineSolutionsTitrimetryWaterJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

D Rotticci, T Norin, K Hult, M Martinelle. 2000-01-03. An active-site titration method for lipases.. https://doi.org/10.1016/s1388-1981(99)00168-7

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