Secreted expression of self-assembling proteins in Pichia pastoris
09 / 2006 - 09 / 2010
Introduction: Fibrous proteins like collagen, silk or elastine have the propensity to adopt a regular structure and to self-assemble originating supramolecular structures like crystallites, tapes, fibrils and gels. Their primary structure is in most cases highly repetitive and often consists of periodic repetition of blocks that, in turn, contain many tandem repeats like Gly-Ala, Val-Pro-Gly-Val, Gly-Pro-Ala. It is due to the self-assembling properties as well as to the repetitiveness of the protein sequence that, their biological production is often subject to challenges uncommon in globular protein (enzyme) production, for example gene instability, proteolytic degradation at repetitive sites, absence of suitable chaperons and unwanted intracellular assembly of supramolecular structures which could impair the normal functioning of the cell. Aim: This project aims at the successful secretion of self-assembling heterologous proteins in Pichia pastoris. Research: Enhancement of the production host compatibility with the designer protein or production of non-interacting (soluble) precursor molecules, followed by in-vitro modification of the precursor into the mature self-assembling form.