Jump to main content
Jump to site search

Issue 24, 2006
Previous Article Next Article

Natural sialoside analogues for the determination of enzymatic rate constants

Author affiliations

Abstract

Two isomeric 4-methylumbelliferyl-α-D-N-acetylneuraminylgalactopyranosides (1 and 2) were synthesised. These compounds contain either the natural α-2,3 or α-2,6 sialyl–galactosyl linkages, as well as an attached 4-methylumbelliferone for convenient detection of their hydrolyses. These compounds were designed as natural sialoside analogues to be used in a continuous assay of sialidase activity, where the sialidase-catalysed reaction is coupled with an exo-β-galactosidase-catalysed hydrolysis of the released galactoside to give free 4-methylumbelliferone. The kinetic parameters for 1 and 2 were measured using the wild-type and nucleophilic mutant Y370G recombinant sialidase from Micromonospora viridifaciens. Kinetic parameters for these analogues measured using the new continuous assay were in good agreement with the parameters for the natural substrate, 3′-sialyl lactose. Given the selection of commercially available exo-β-galactosidases that possess a variety of pH optima, this new method was used to characterise the full pH profile of the wild-type sialidase with the natural sialoside analogue 1. Thus, use of these new substrates 1 and 2 in a continuous assay mode, which can be detected by UV/Vis or fluorescence spectroscopy, makes characterisation of sialidase activity with natural sialoside linkages much more facile.

Graphical abstract: Natural sialoside analogues for the determination of enzymatic rate constants

Back to tab navigation

Publication details

The article was received on 25 Sep 2006, accepted on 10 Oct 2006 and first published on 30 Oct 2006


Article type: Paper
DOI: 10.1039/B613909D
Citation: Org. Biomol. Chem., 2006,4, 4453-4459
  •   Request permissions

    Natural sialoside analogues for the determination of enzymatic rate constants

    D. Indurugalla, J. N. Watson and A. J. Bennet, Org. Biomol. Chem., 2006, 4, 4453
    DOI: 10.1039/B613909D

Search articles by author

Spotlight

Advertisements