Proteinase extraction and purification - (Oct/08/2014 )

Hi all, for my project I am wondering what would be the best method to extract aspartic proteinases from the leaves of Urtica dioica (stinging nettle). I plan to centrifuge the extract to purify what proteins are present- just would like to know how would one conduct this and would I need buffers or other chemicals? Thanks in advance:)

yes, you'll need buffer, salt, stabilizing agent(s) (edta, dtt, ...). normally you should include protease inhibitors but since you are trying to purify a protease you should omit them (or, at least, the ones that will inhibit your protease of interest). if you omit then you will have to work quickly and in conditions which will reduce proteolytic activity. you also should hope that your protease of interest doesn't autolyse.

check the literature to see if others have purified your protease or a similar one and the conditions they used.