I am trying to extract my membrane bound plant protein with different extraction buffers but i am unable to extract most of it. So can anyone suggest a extraction buffer ?
Extraction of membrane proteins usually involves a similar procedure, with isolation of the cell membrane followed by extraction of membrane proteins from them. I suppose you can do the following:
Pellet down the cells (the rcf would depend upon the type of cell you are using)
Lyse them using a french press or a high-pressure homogenizer.
Spin down large debris at ~6000g for 15 minutes.
Take the supernatant and pellet the suspended cell membranes through ultracentrifugation at ~120000g for 60-90 minutes.
Collect the pellets and resuspend them in HEPES/Tris buffer saline at near-neutral pH (works for most of the cases) using a rotor-stator homogenizer. The volume of resuspension depends upon the amount of cell membrane pelleted. One can use about 25ml buffer to resuspend 3-4 g of membranes.
Add n-dodecyl-beta-D-maltopyranoside to a final concentration of 20 mM. incubate the suspension 4C at constant nutation/gentle stirring for ~120 minutes (Make sure that the suspension does not froth!)
If there is an overexpression of the protein, usually the suspension clears out. In either case, proceed to ultracentrifugation at ~100000g for 60 minutes.
Proceed with usual affinity chromatography using the centrifuged supernatant.
Following this, you will have to optimize your detergent for size exclusion chromatography separately.
you might also need to consider different tags at different positions if you feel that a certain domain that harbours the tag is getting cleaved off during the purification process, resulting in low yield.