the problem of protein degradation

Hello everyone,



I am working on one of transposase proteins. When I tried to extract the
endogenous protein, I found a very strange problem. I can only get the
truncated form of this protein if without SDS in the extraction buffer. If I
added SDS in the protein extraction buffer, it will inhibit the protein
degradation. Triton X-100 has no any effect on the protein degradation. High
concentration of protease inhibitors cocktail (Sigma; for plant tissue
extraction) also failed to inhibit the protein degradation. Can someone
please suggest me how to prevent the protein degradation in the extraction
process? Any comments are welcome!



Thanks in advance.



Gang