Sfh-I, a Subclass B2 Metallo-β-Lactamase from a Serratia fonticola Environmental Isolate

Abstract
An environmental isolate of Serratia fonticola resistant to carbapenems was shown to contain a genetic determinant encoding a metallo-β-lactamase of the subclass B2. The Sfh-I enzyme exhibits some divergence from the previously characterized enzymes of this subclass. This is the first example of a naturally occurring metallo-β-lactamase in Enterobacteriaceae.