[johndohnal]

Are there any known enzymes which cleave the sidechains (not backbones) of lysine or arginine?  Smaller enzymes would be better.  If no known enzymes which cleave lysine or arginine, then any enzymes which cleave the sidechains of any amino acids would be appreciated.

Thanks,
John

[Babcock_Hall]

It is difficult even to envision how one would remove a side chain ammonium ion (lysine).  I don't know of any enzymes that act on these two side chains, but there are chemical reagents which react with one or the other side chain.