Neo-glycopeptides: the importance of sugar core conformation in oxime-linked glycoprobes for interaction studies.
Carbohydrate binding proteins, such as lectins, are crucial in numerous biological recognition processes. While binding may be mediated by a single monosaccharide, several lectins have shown exquisite epimer and linkage recognition indicating that a larger structure is essential for optimal interaction. Several approaches have been described for their detailed study, including lectinosorbent assays, microarrays and surface plasmon resonance (SPR). Most of these approaches ignore that the aglycon-bound monosaccharide is often in a non-natural conformation that affects the occurring binding event. In this paper we demonstrate that oxime-bound glycans, employed in such approaches, occur predominantly in the open form (approximately 70%). Through the use of a secondary amine, the aglycon-bound monosaccharide in the resulting neo-glycopeptide probe is forced into the ring-form. Resulting structures were analyzed by means of nuclear magnetic resonance and differential derivatization experiments. The impact of ring closure was further demonstrated through interaction studies using SPR and various lectins with distinct binding specificities.
Jiménez-Castells
Carmen
C
Department of Experimental and Health Sciences, Pompeu Fabra University, Barcelona Biomedical Research Park, Dr. Aiguader 88, 08003, Barcelona, Spain.
de la Torre
Beatriz G
BG
Andreu
David
D
Gutiérrez-Gallego
Ricardo
R
D000595:Amino Acid Sequence; D000625:Aminooxyacetic Acid / Q000737:chemistry; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D006020:Glycopeptides / Q000737:chemistry*; D007700:Kinetics; D007785:Lactose / Q000737:chemistry; D037102:Lectins / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D015335:Molecular Probes / Q000737:chemistry*; D008969:Molecular Sequence Data; D010091:Oximes / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D020349:Surface Plasmon Resonance
D006020:Glycopeptides; D037102:Lectins; D015335:Molecular Probes; D010091:Oximes; D000625:Aminooxyacetic Acid; D007785:Lactose