Nightmare with GST fusion protein

[Jean-Yves Masson]

Dear netters,

        Since two months, no matter what I do, my GST fusion protein is 
degraded in E. coli. I tried the following without any result:

- Different hosts (XL-1 blue, DH5 alpha, HB101, BL21 and AD202)
- Time course: my protein is cleaved in less than 30 min after IPTG 
induction (then my fusion protein is 31 kD instead of 66 kD)
- Different protease inhibitors
- Growth at 30 C instead of 37 C.
 
        I would really appreciate if somebody could help me with this puzzle.


Jean-Yves Masson
Laboratoire d'endocrinologie moleculaire
2705 Boul. Laurier
Ste-Foy, Quebec
G1V 4G2
Tl.: (418) 654-2296
FAX: (418) 654-2761
E-mail: MASSONJY at RSVS.ULAVAL.CA