Carbohydrate structure, terminal

Oligolysine dendrimers with terminal carbohydrate structures were functionalised by solid-phase synthesis for well-defined construction of glycoclusters . Synthesis proceeded via coupling of lysine molecules. Eight amino groups are attached by peptide bonding to the periphery via a spacer-functionalised sialic acid derivative (Fig. 8.8). 

Table 1 summarizes the carbohydrate structural data deduced from the three detection methodologies, MALDI-TOF, ES-MS, and high pH anion exchange chromatography. The N-glycosylation site proved to be occupied with several structures. The glycopeptides were partially separated as five peptides, at retention times of 19.4, 20.3, 20.7, 20.9, and 21.3 minutes, and all of these glycopeptides contained the same amino acid sequence, N-terminal amino acids 1-17. 

The techniques developed for the LF 3600 N-terminal protein sequencer (Beckman Instr.) provide a fast and efficient way to positively identify Ser (0-linked Sac), -Thr (0-linked Sac) and Asn (N-linked Sac) carbohydrate structures during N-terminal sequence analysis (Gooley et al., 1995). Liquid phase anhydrous trifluoroacetic acid (TEA) is used to extract glycosylated, polar amino acid derivatives from the reaction cartridge. These amino acids are then converted into PTH derivatives which can be... 

These interactions involve adhesion proteins called selectins, which are found both on the rolling leukocytes and on the endothelial cells of the vascular walls. Selectins have a characteristic domain structure, consisting of an N-terminal extracellular lectin domain, a single epidermal growth factor (EGR) domain, a series of two to nine short consensus repeat (SCR) domains, a single transmembrane segment, and a short cytoplasmic domain. Lectin domains, first characterized in plants, bind carbohydrates... 

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