| abstract |
Peptides can be produced in and purified from the milk of transgenic animals. The peptides are made as fusion proteins with a suitable fusion partner such as .alpha.-lactalbumin, which is a natural milk protein. The fusion partner protein acts to promote secretion of the peptides and, at least in the case of .alpha.-lactalbumin, allows a single-step purification based on specific affinity. The peptide is released from the purified fusion protein by a simple cleavage step and purified away from the now liberated .alpha.-lactalbumin by repeating the same affinity purification method. A particular advantage of producing peptides via this route, in addition to the obvious advantages of high yield and biocompatibility, is that specific post-translational modifications, such as carboxy terminal amidation, can be performed in the mammary gland. |