Metallobétalaktamázok

Metallobétalaktamázok, often abbreviated as MBLs, are a class of enzymes that confer antibiotic resistance to bacteria. These enzymes function by hydrolyzing the beta-lactam ring, a crucial structural component of many antibiotics, including penicillins, cephalosporins, and carbapenems. This hydrolysis renders the antibiotic inactive, making it ineffective against the bacterial infection.

The "metallo" prefix in metallobétalaktamázok refers to the presence of one or more metal ions, typically zinc, in the enzyme's active site. These metal ions are essential for the catalytic activity of the enzyme, playing a direct role in the breakdown of the beta-lactam ring. The diversity of MBLs is considerable, with numerous subclasses identified based on their amino acid sequences and substrate specificities.

The genes encoding MBLs are often located on mobile genetic elements, such as plasmids, which facilitates their rapid spread among bacterial populations. This horizontal gene transfer is a major driver of the increasing prevalence of antibiotic-resistant bacteria, posing a significant threat to public health. Infections caused by MBL-producing bacteria are notoriously difficult to treat, as they are often resistant to nearly all available beta-lactam antibiotics.

The emergence and dissemination of metallobétalaktamázok have led to a critical need for the development of novel therapeutic strategies. Research efforts are focused on designing new antibiotics that are not susceptible to MBL hydrolysis or on developing inhibitors that can block the activity of these enzymes, thereby restoring the efficacy of existing antibiotics.