1.   Protein A-fusion proteins were purified by IgG-Sepharose chromatography according to the manufacturers instructions.

2.   Applied Biosystems uses various techniques to purify proteins and break them down into their components.

3.   But the difficulties and costs involved in extracting and purifying these proteins from plant tissue has prevented the process from being adopted on a large scale.

4.   Putting the gene for the human protein into animals and then purifying the protein from milk is a cheaper alternative, backers say.

5.   The silk proteins are purified out of the milk into a whitish liquid with the consistency of maple syrup and then spun into fibers.

6.   So far, the team from the Faculty of Pharmacy and Pharmaceutical Sciences at the University of Alberta, Canada, has only isolated and purified the protein.