Biochemistry (Moscow)

, Volume 71, Issue 5, pp 496–504

Probing sialic acid binding Ig-like lectins (siglecs) with sulfated oligosaccharides

  • E. M. Rapoport
  • G. V. Pazynina
  • M. A. Sablina
  • P. R. Crocker
  • N. V. Bovin
Article

DOI: 10.1134/S0006297906050051

Cite this article as:
Rapoport, E.M., Pazynina, G.V., Sablina, M.A. et al. Biochemistry (Moscow) (2006) 71: 496. doi:10.1134/S0006297906050051

Abstract

Soluble siglecs-1,-4,-5,-6,-7,-8,-9, and-10 were probed with polyacrylamide glycoconjugates in which: 1) the Neu5Ac residue was substituted by a sulfate group (Su); 2) glycoconjugates contained both Su and Neu5Ac; 3) sialoglycoconjugates contained a tyrosine-O-sulfate residue. It was shown that sulfate derivatives of LacNAc did not bind siglecs-1,-4,-5,-6,-7,-8,-9, and-10; binding of 6′-O-Su-LacNAc to siglec-8 was stronger than binding of 3′SiaLacNAc. The relative affinity of 3′-O-Su-TF binding to siglecs-1,-4, and-8 was similar to that of 3′SiaTF. 3′-O-Su-Lec displayed two-fold weaker binding to siglec-1 and siglec-4 than 3′SiaLec. The interaction of soluble siglecs with sulfated oligosaccharides containing sialic acid was also studied. It was shown that siglecs-1,-4,-5,-6,-7,-9, and-10 did not interact with these compounds; binding of 6-O-Su-3′SiaLacNAc and 6-O-Su-3′SiaTF to siglec-8 was weaker than that of the corresponding sulfate-free sialoside probes. Siglec-8 displayed affinity to 6′-O-Su-LacNAc and 6′-O-Su-SiaLex, and defucosylation of the latter compound led to an increase in the binding. Sialoside probes containing tyrosine-O-sulfate residue did not display increased affinity to siglecs-1 and-5 compared with glycoconjugates containing only sialoside. Cell-bound siglecs-1,-5,-7, and-9 did not interact with 6-O-Su-3′SiaLacNAc, whereas the sulfate-free probe 3′SiaLacNAc demonstrated binding. In contrast, the presence of sulfate in 6-O-Su-6′SiaLacNAc did not affect binding of the sialoside probe to siglecs. 6′-O-Su-SiaLex displayed affinity to cell-bound siglecs-1 and-5; its isomer 6-O-Su-SiaLex bound more strongly to siglecs-1,-5, and-9 than SiaLex.

Key words

sialic acidsiglecssulfated oligosaccharidescarbohydrate specificity

Abbreviations

BSA

bovine serum albumin

CHO-siglec

CHO cells transfected with siglec vector

fluo

fluorescein

Glyc-PAA

polyacrylamide glycoconjugate

PBA

PBS containing 0.2% BSA

PBS

phosphate buffered saline containing 0.01 M Na2HPO4, 0.01 M NaH2PO4, 0.15 M NaCl, pH 7.3

siglec-Fc

chimeric protein containing full-sized extracellular region hSiglec and Fc region of human IgG

sTyr

sulfotyrosine (tyrosine-O-sulfate)

TBS

50 mM Tris-HCl buffer containing 150 mM NaCl, pH 7.5

TBA

TBS containing 0.2% BSA

Versene solution

PBS containing 0.02% EDTA

Copyright information

© Pleiades Publishing, Inc. 2006

Authors and Affiliations

  • E. M. Rapoport
    • 1
  • G. V. Pazynina
    • 1
  • M. A. Sablina
    • 1
  • P. R. Crocker
    • 2
  • N. V. Bovin
    • 1
  1. 1.Shemyakin and Ovchinnikov Institute of Bioorganic ChemistryRussian Academy of SciencesMoscowRussia
  2. 2.The Wellcome Trust Biocentre, School of Life SciencesUniversity of Dundee DD1 5EHScotlandUK