Key Findings

The study characterizes several novel TEM-type β-lactamases in Proteus mirabilis, including TEM-57, TEM-66, TEM-65, TEM-73, and TEM-74, along with previously known variants such as TEM-1, TEM-2, TEM-3, TEM-24, and TEM-44. These enzymes exhibit varying degrees of resistance to β-lactam antibiotics, particularly amoxicillin, ticarcillin, piperacillin, and cephalothin, with some showing extended-spectrum activity against broader classes of β-lactams.