[Protein-analysis] protein candidate

[assa sittner]

Hi There,
I need for some biochemical assay, a simple protein that fulfills the
following requirements:
1. very stable (no significant degradation)
2. soluble
3. monomeric
4. Mw > 70 KDa
5. easily expressed and purified from E.coli
6. if possible, has an enzymatic activity that can be quantified
is it too much to ask?
ideas anyone?

(I was thinking beta galactosidase, but couldn't find an article with nice
gels that show the purity, and data about stability etc. is there something
else?)

have a nice day,