Print

Print

Hello Rajesh
  We serendipitously encountered three cases where a contaminating fungus led to proteolysis of the proteins, which was required for their crystallization. We identified the fungus by sequencing a little bit of its genome, and found that it is Penicillium!

  Here are two of the papers -

Mandel CR, Gebauer D, Zhang H, Tong L. (2006). A serendipitous discovery that in situ proteolysis is essential for the crystallization of yeast CPSF-100 (Ydh1p). Acta Cryst. F62, 1041-1045.

Bai Y, Auperin TC, Tong L. (2007). The use of in situ proteolysis in the crystallization of murine CstF-77. Acta Cryst. F63, 135-138.


best regards
Liang


----
Liang Tong, William R. Kenan, Jr. Professor and Chair
Department of Biological Sciences
Columbia University, New York, NY 10027          
(212) 854-5203
[log in to unmask]
http://tonglab.biology.columbia.edu




On Fri, Mar 9, 2018 at 3:25 PM, Rajesh <[log in to unmask]> wrote:

Dear BB,

I apologize for the off topic. But I strongly believe this is the right place to ask my question.

We are working on a protein that is 300 amino acids in length. After many efforts, we could solve the structure at 1.60 Å resolution. It took almost 10 months to get this crystal and we could not reproduce it. The maps are interpretable and we could model only till residue 190 and we could not see any density for the rest of the molecule. My question is- Does anyone has encountered such a structure with lots of missing density? I would appreciate your efforts if someone can send me few references describing such type of structures. Is there any chance that microbes can cleave the protein in the crystal drops?

 

 

Thanks,

Rajesh..