i am getting two bands of my purified protease on sds page.can anyone tell me the easy way to check the nature of two bands?

it could be either Post-translational modification or self aggregation.
to test if it is self aggregation, add 4M Urea to your gel to see if it resolved to one single band

good luck

hi

Here are some possibilities for your problem.
if you are using BME (old)in your sample buffer that may also show 2 bands on sds.

If R u using precasting gels some times may be becoz of prepartion or exprd that also give u the same result.

U can try out by doing the RP HPLC.

If possible put the picture that may useful for some analysis.