Beta-Lactamases (BetaLs), are a large family of hydrolases comprising more than 850 identified members expressed in Gram-positive and Gram-negative bacteria. BetaLs can be classified according to their substrate or inhibitor specificity. These enzymes are capable of hydrolyzing four atom rings known as Beta-lactams. Antibiotics containing Beta-lactam rings (i.e. penicillin, cephalosporin, monobactam, carbapenem) are highly susceptible to be hydrolyzed via enzymatic activity, which deactivates their antibiotic potency. BetaLs have become a significant clinical threat due to the alarming number of cases of bacterial strains showing Beta-lactam antibiotic resistance. Assay Genie's Beta-Lactamase Activity Assay Kit offers a simple and sensitive assay that can detect and quantify the enzymatic activity of these hydrolases. The assay is based on the hydrolysis of Nitrocefin, a chromogenic cephalosporin, that results in the generation of a colored product (OD 490 nm), which is directly proportional to the amount of BetaL activity. The assay can detect enzymatic activity as low as 0.06 mU in a variety of biological samples.

Figure: a) Nitrocefin Standard Curve. b) βL activity in E. coli culture (5 μl), contaminated media (CM; 30 μl) & Positive Control (4 μl). c) βL Activity of E.Coli and contaminated media expressed per milligram of protein. Assay was performed following the kit protocol.