Yeast could have a use in the manufacture of medicines, as well as in brewing beer and baking bread, after scientists genetically engineered a yeast culture to make it able to secrete human proteins.

The breakthrough could allow yeast to be turned into a “medicine factory”, churning out therapeutic proteins for the treatment of diseases from cancer to multiple sclerosis.

It is thought that yeast and other fungi could provide a cheaper and more productive source of protein-based drugs than the mammalian cell lines now commonly used.

The US team altered a bio-chemical pathway in the yeast Pichia pastoris, enabling it to produce complex and uniform human glycoproteins. These are proteins with a particular kind of sugar coating.

Until now, the inability to decorate human proteins with the right assortment of sugar molecules – a process called glycosylation – has prevented the production of therapeutics from fungi.

Professor Tillman Gerngross, from Dartmouth College, New Hampshire, who co-led the research, said: “For the first time, we have shown that yeast can be used to produce a complex human glycoprotein. This technology has the potential to revolutionise the way therapeutic proteins are made.”

Researcher Stefan Wildt, from the biotech firm GlycoFi, said: “The protein structures we are seeing in our yeast are of a purity and uniformity unprecedented in biopharmaceutical manufacturing.

“This makes it possible to harness the inherent advantages of fungal protein expression systems and the potential to increase pharmaceutical production, ultimately improving patient access to life-saving drug therapies.”

More here.