His-tag like proteins in E. coli?

[Peter Frank]

Hello,

I used an anti-His-tag antibody in order to detect the His-tagged
protein that I expressed in E.coli (strain BL21 (DE3)). I also used a
negative control with no His-tagged protein expression and got some
bands there.

Are there any proteins naturally occuring in E.coli which contain
His-tag like segments that will bind anti-His-tag antibody?

Peter