Re: [ccp4bb] update--degradation of MBP fusion protein

2010-10-21 Thread Ho Leung Ng 
Hi Jerry,

 Try parameters that slow the rate of protein production, such as
expressing at lower temperature, using less IPTG/inducing agent, or
using a weaker promoter.


Good luck,
Ho

[ccp4bb] update--degradation of MBP fusion protein

2010-10-20 Thread Jerry McCully 

Dear ALL;

Firstly I'd like to thank folks for the various suggestions to handle the 
degradation of MBP fusion protein.

According to these suggestions, I have tried shortening the linker between 
MBP and target protein.

We can get decent yield of the full-length protein now.

We still have a little question about the expression.

 Using BL21(De3 ) star cells at 37 degree, we got good soluble expression 
of the MBP fusion protein. However, the majority of the proteins were existing 
as soluble aggregates and only a small protion of proteins was purified as 
monomers. 

 Does anyone have the experience to increase the yield of the monomeric 
proteins?

  Thanks a lot,

Jerry McCully