DUBLIN – A certain DNA endonuclease from Streptococcus pyogenes, Cas9, has gained enormous prominence as part of the revolutionary CRISPR-Cas9 genome editing system, but Hansa Medical AB is making waves with a different enzyme from the same bug, an endopeptidase that chews up immunoglobulin G (IgG) antibodies and which could reduce the risk of kidney transplant rejection in high-risk patients.