Strategies for the synthesis of peptides applied biotechnology

MARANI MARIELA M.

Parnaíba

Workshop; Biosensors & Biotechnology. Proteomics and Nanobiosensors: A new concept for GMO assessment.; 2014

Universidad federal do Piauí-BIOTEC

Peptides are short chains of amino acids linked by amide bonds. They can be used in immuno sensors as a probe (attached ligand) or as an analyte (sample detection). In both cases is necessary to have a good amount of the peptide of interest during the laboratory development stage. Solid phase peptide synthesis (SPPS) was a major breakthrough allowing for the chemical synthesis of peptide molecules. SPPS results in high yields of pure products and works more quickly than classical synthesis (liquid-phase peptide synthesis, LPPS), offering additional advantages such as simplicity, less cost and suitable for automation. In SSPS, small porous insoluble solid beads are treated with functional units (coupling agents) on which the peptide chains are constructed. The peptide is thus immobilized on the solid phase and remains anchored during the filtering process, whereas the liquid phase reactants and synthesis by-products are removed. The SPPS follows a general pattern of repeated cycles of coupling-wash-deprotection-wash and the peptide remains covalently attached to the bead until it is cleaved by reagents. Depending on the use of the peptide, different resins, linkers, and properties of the peptide synthesized (such as sequence, amino acid composition and length) have to take into consideration for chemical stability, solubility and high yields. In the context of GMOsensor project, diverse strategies to synthesize, purify and immobilize peptides are presented with the objective of exchange core scientific knowledge. Discussion about advantages and disadvantages of the use of peptides as ligands or as analytes in the development of analytical devices for the detection of GMO in food and feed will be done.