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Solution structure and activity of mouse lysozyme M.

T Obita·T Ueda·T Imoto
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Abstract

The three-dimensional structure of mouse lysozyme M, glycoside hydrolase, with 130 amino acids has been determined by heteronuclear NMR spectroscopy. We found that mouse lysozyme M had four alpha-helices, two 3(10)helices, and a double- and a triple-stranded anti-parallel beta-sheet, and its structure was very similar to that of hen lysozyme in solution and in the crystalline state. The pH activity profile of p-nitrophenyl penta N-acetyl-beta-D-chitopentaoside hydrolysis by mouse lysozyme M was similar to that of hen lysozyme, but the hydrolytic activity of mouse lysozyme M was lower. From analyses of binding affinities of lysozymes to a substrate analogue and internal motions of lysozymes, we suggest that the lower activity of mouse lysozyme M was due to the larger dissociation constant of its enzyme-substrate complex and the restricted internal backbone motions in the molecule.

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Amino Acid SequenceAnimalsChickensChitinGlucosidesHumansHydrogen-Ion ConcentrationKineticsMagnetic Resonance SpectroscopyMiceModels, MolecularMolecular Sequence DataMuramidaseOligosaccharidesProtein ConformationProtein Structure, SecondaryProtein Structure, TertiarySolutionsSubstrate SpecificityComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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T Obita, T Ueda, T Imoto. 2003. Solution structure and activity of mouse lysozyme M.. https://doi.org/10.1007/s000180300012

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