rhGH-affinity-peptide selection using combinatorial libraries.

M.M. MARANI; M.C. MARTÍNEZ CERON; G. FORNO; F. ALBERICIO; O. CASCONE; S.A. CAMPERI

Puerto Madryn, Chubut, Argentina

Otro; XLVI Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2010

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Growth hormone (hGH) is used in medicine to treat children´s growth disorders and adultgrowth hormone deficiency. High purity is necessary for its parenteral administration.Thus, downstream processing should be optimized to obtain higher yields and low costprocesses. Affinity Chromatography (AC) is considered an efficient method for proteinpurification in complex mixtures. Short peptides are ideal ligands for industrial separationsbecause of its low cost, high stability and easy manufacture.We synthesized a peptide combinatorial library XXOXXOOO (O=fixed and X=variablepositions) using Divide-couple-recombine (DCR) method that allows obtaining a librarywith all possible combinations of amino acids in the form of "one bead-one peptide".Peptide ligands can be selected from library screening. We have developed a rapid and nonexpensivestrategy for peptide identification contained on positive beads, by using MALDITOF-MS, and 4-hydroxymethylbenzoic acid. We selected more than 50 peptides withrhGH affinity using this strategy. The peptides showed consensus sequences. Thosepeptides could be used not only as affinity ligands for new strategies development based onAC rhGH purification but also as diagnostic-rhGH-kits ligands. This kind of systems couldimprove cost/benefit ratio obtaining economically competitive products.