Probing a CMP-Kdn synthetase by 1H, 31P, and STD NMR spectroscopy.

Biochem Biophys Res Commun

Institute for Glycomics, Griffith University (Gold Coast Campus), PMB 60 Gold Coast Mail Centre, Queensland 9726, Australia.

Published: February 2005

CMP-Kdn synthetase catalyses the reaction of sialic acids (Sia) and cytidine-5'-triphosphate (CTP) to the corresponding activated sugar nucleotide CMP-Sia and pyrophosphate PP(i). STD NMR experiments of a recombinant nucleotide cytidine-5'-monophosphate-3-deoxy-d-glycero-d-galacto-nonulosonic acid synthetase (CMP-Kdn synthetase) were performed to map the binding epitope of the substrate CTP and the product CMP-Neu5Ac. The STD NMR analysis clearly shows that the anomeric proton of the ribose moiety of both investigated compounds is in close proximity to the protein surface and is likely to play a key role in the binding process. The relative rates of the enzyme reaction, derived from (1)H NMR signal integrals, show that Kdn is activated at a rate 2.5 and 3.1 faster than Neu5Ac and Neu5Gc, respectively. Furthermore, proton-decoupled (31)P NMR spectroscopy was successfully used to follow the enzyme reaction and clearly confirmed the appearance of CMP-Sia and the inorganic pyrophosphate by-product.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2004.12.040DOI Listing

Publication Analysis

Top Keywords

cmp-kdn synthetase
12
std nmr
12
nmr spectroscopy
8
enzyme reaction
8
nmr
5
probing cmp-kdn
4
synthetase
4
synthetase 31p
4
31p std
4
spectroscopy cmp-kdn
4

Similar Publications

Identification of a Kdn biosynthesis pathway in the haptophyte suggests widespread sialic acid biosynthesis among microalgae.

J Biol Chem

October 2018

From the Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom

Sialic acids are a family of more than 50 structurally distinct acidic sugars on the surface of all vertebrate cells where they terminate glycan chains and are exposed to many interactions with the surrounding environment. In particular, sialic acids play important roles in cell-cell and host-pathogen interactions. The sialic acids or related nonulosonic acids have been observed in Deuterostome lineages, Eubacteria, and Archaea but are notably absent from plants.

View Article and Find Full Text PDF

CMP-Kdn synthetase catalyses the reaction of sialic acids (Sia) and CTP to the corresponding activated sugar nucleotide CMP-Sia and pyrophosphate PP( i ). Saturation Transfer Difference (STD) NMR spectroscopy has been employed to investigate the sub-structural requirements of the enzyme's binding domain. Sialylnucleoside mimetics, where the sialic acid moiety has been replaced by a carboxyl group and a hydrophobic moiety, have been used in NMR experiments, to probe the tolerance of the CMP-Kdn synthetase to such replacements.

View Article and Find Full Text PDF

Probing a CMP-Kdn synthetase by 1H, 31P, and STD NMR spectroscopy.

Biochem Biophys Res Commun

February 2005

Institute for Glycomics, Griffith University (Gold Coast Campus), PMB 60 Gold Coast Mail Centre, Queensland 9726, Australia.

CMP-Kdn synthetase catalyses the reaction of sialic acids (Sia) and cytidine-5'-triphosphate (CTP) to the corresponding activated sugar nucleotide CMP-Sia and pyrophosphate PP(i). STD NMR experiments of a recombinant nucleotide cytidine-5'-monophosphate-3-deoxy-d-glycero-d-galacto-nonulosonic acid synthetase (CMP-Kdn synthetase) were performed to map the binding epitope of the substrate CTP and the product CMP-Neu5Ac. The STD NMR analysis clearly shows that the anomeric proton of the ribose moiety of both investigated compounds is in close proximity to the protein surface and is likely to play a key role in the binding process.

View Article and Find Full Text PDF

In this report we present kinetic data of the activation reaction of several synthetic 3-deoxy-D-glycero-D-galacto-nonulosonic acid (Kdn) and N-acetylneuraminic acid (Neu5Ac) analogues catalyzed by the rainbow trout testis CMP-Kdn synthetase. This enzyme showed broad substrate specificity in terms of substitutions at C4 or C5 position of Kdn and Neu5Ac. In contrast, calf brain CMP-N-acylneuraminic acid synthetase had narrow substrate specificity, being active only on various N-acyl analogues of Neu5Ac and only slightly active on Kdn derivatives.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!