Protease specificity

[Paul]

rwn wrote:

> Hi there
>
> Does anyone have information regarding the specificity of
> proteases. I am interested in comparing proteases normally
> used for cleaving fusion proteins i.e. factor Xa and
> thrombin.
>
>

A few years ago I had problems with Factor Xa cleaving within
one of my proteins as well as at the linker between it and MBP
(from Biolabs' pMAL-c2).  I asked their tech support and was
told that FXa will sometimes cleave at sites that resemble or contain
a partial recognition sequence: i.e E/D-G-R or even G-R instead
of the canonical I-E/D-G-R.  This made sense form the size of the
unwanted fragments and sequence of my protein.  No references
for this I'm afraid.

Cheers

Paul Digard