Towards molecular farming in the future: pichia pastoris-based production of single-chain antibody fragments.

This review article focuses on the use of the methylotrophic yeast Pichia pastoris as a recombinant protein-expression system. P. pastoris is a useful system for the expression of milligram-to-gram quantities of a protein, which can be scaled up to fermentation to meet greater demands. Compared with mammalian cells, Pichia do not require a complex growth medium or culture conditions, they are as easy to manipulate genetically as Escherichia coli and have a eukaryotic protein-synthesis pathway. They seem suited to laboratory-scale production of recombinant proteins for in-house use or, in some cases, molecular farming of recombinant products. This review article focuses on the use of P. pastoris, describes a fermentation production run of a single-chain antibody fragment and includes a discussion of fermentation as a production strategy.