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Θ / (deg cm 2 dmol -1 )synthesis on solid phase was employed (Figure 3). The synthesis was carried out on2-chlorotrityl resin, which was preloaded with Fmoc-alanine. The glycosylated amino acidwas added manually. The elongation was executed by sequential addition of the aminoacids and the coupling reagent. In the case of unglycosylated residues the coupling reagentTBTU was used, while HATU and HOAt were employed for the coupling of theglycosylated amino acids. The entire synthesis of the glycopeptides was carried out at amaximum temperature of 40 °C to avoid cleavage of carbohydrate from the peptidebackbone [2].Structural AnalysisProline containing glycopeptides and the corresponding backbones were synthesized toenforce a polyprolin type II helix:Circular dichroism (CD) analysis (c = 40-5000-10000-15000-20000-25000-30000[AAT(GalNAc)] 3PA[AAT] 3PA[AAT(GalNAc)] 2PAT(GalNAc)AAT(GalNAc)PA[AAT] 2PATAATPA[AAT(GalNAc)] 3PAT(GalNAc)PA[AAT] 3PATPA[AAT(GalNAc)] 4PA-35000190 200 210 220 230 240 250λ / nmFig. 4. CD analysis (c = 4 mg/mL,Millipore water, rt) of AFGP analogs.Microphysical AnalysisOptical microphotographs of ice crystals(Figure 5) show altered crystal habitusand no Ostwald ripening in the presenceof AFGP analogs b) in comparison to theabsence of any AFGPs a). In detail theresults indicate that larger ice crystalsgrow at the expense of smaller ones.Another implication is visible in analtered morphology of the ice crystals. Inpresence of AFGPs the faces of the icecrystals grow at a much slower rate witha hexagonal bipyramidal habitus [3].AcknowledgmentsThis work is supported by the DFG (SFB 613).mg/mL, Millipore water, rt) of AFGPanalogs containing proline residues show amaximum at ~220 nm and a minimum at~198 nm (Figure 4). The signature ofpolyproline II helical structure is significant,but with similarity to a random coil withhigh flexibility. Temperature-dependentspectra were measured, which show theexistence of an isodichroic point indicatinga local two-state population of e.g.polyproline II helix and random coil.Furthermore it is obvious that the CDminima of the glycosylated peptides are lesspronounced and a display of a slight redshiftin comparison to the correspondingaglycons is visible.Fig. 5. Optical microphotographs of icecrystals (aq. 45 wt % sucrose solutions,-8 °C).References1. Tachibana, Y., Fletcher, G.L, Fujitani, N., Tsuda, S., Monde, K., Nishimura, S. Angew.Chem. 116, 874-880 (2004); Angew. Chem. Int. Ed. 43, 856-862 (2004).2. Heggemann, C., Budke, C., Schomburg, B., Majer, Z., Wißbrock, M., Koop, T., Sewald, N.Amino Acids 38 (1), 213-222 (2010).3. Budke, C., Heggemann, C., Koch, M., Sewald, N., Koop, T. J. Phys. Chem. B 113 (9),2865-73 (2009).87