RESUMO
The attraction of nucleic acids to lipidic compartments is the first step for carriers of potentially inheritable information to self-organise in functionalised synthetic cells. Confocal fluorescence imaging shows that a synthetic amphiphilic peptidyl RNA molecule spontaneously accumulates at the outer bilayer membranes of phospho- and glycolipidic giant vesicles. Cooperatively attractive interactions of -3.4 to -4.0 kcal mol(-1) between a random coil hydrophobic peptide and lipid membranes can thus pilot lipophobic RNA to its compartmentation. The separation of mixed lipid phases in the membranes further enhances the local concentration of anchored RNA.
Assuntos
Bicamadas Lipídicas/química , Peptídeos/química , RNA/química , Interações Hidrofóbicas e Hidrofílicas , Lipídeos de Membrana/química , Peptídeos/síntese química , Tensoativos/síntese química , Tensoativos/químicaRESUMO
We report the design, synthesis, and immunological evaluation of a series of glycopeptide analogues of the previously described antigenic probe CSF114(Glc), with the aim of understanding the importance of N-glycosylation on Asn residue in multiple sclerosis antibody recognition. The glucopeptide, characterized by a ß-turn conformation which is fundamental for a correct presentation of the epitope, has been modified by introducing various natural glycoamino acids in position 7. The new glycopeptides were evaluated by measuring the IgG and IgM antibody titer in multiple sclerosis patients' and normal blood donors' sera. Moreover, we achieved the efficient synthetic strategy of new Asn derivative bearing N-acetylneuraminic acid (Neu5Ac), linked by an N-glycosidic bond, on the side chain of the Asn residue orthogonally protected for Fmoc/tBu SPPS.
Assuntos
Autoantígenos/química , Glicopeptídeos/química , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Esclerose Múltipla/sangue , Processamento de Proteína Pós-Traducional , Autoantígenos/imunologia , Glicopeptídeos/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/imunologia , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/imunologiaRESUMO
Cu(I)-catalyzed azide-alkyne 1,3-dipolar Huisgen's cycloaddition (CuAAC) is a click reaction that has drawn a lot of attention, in general, and in the field of peptide and protein sciences, in particular. Among several reported applications, the preparation of novel heterodetic cyclopeptides by an intramolecular side chain-to-side chain CuAAC, forming a 1,4-disubstituted[1,2,3]triazolyl-containing bridge, is of great interest. Herein, we provide a detailed protocol for the syntheses of model heterodetic cyclopeptides as a prototypical intramolecular CuAAC, using as a model a sequence derived from parathyroid hormone-related protein.