The phylogeny includes both functional Class B metallo-ß-lactamases, those enzymes that can hydrolyze ß-lactam antibiotics (in boldface and thick lines), and Class B homologs, proteins that have have not been shown to hydrolyze ß-lactam antibiotics or that have been shown to lack that activity (light face and thin lines). ß-lactam hydrolyzing activity arose independently in the Class B and Class E groups

Class B = Subclass B1 + B2 in the Ambler classification scheme

Click here to download the Class B phylogeny with a key that includes accession numbers.

Click here to download the 2003 paper in which phylogenies of metallo-ß-lactamases were published.

Click here to download the 2004 paper in which phylogenies of metallo-ß-lactamases and their homologs were published.