Role of pollution in antibiotic resistance

Antibiotic resistance, is a phenomenon by which a bacterium is resistant to the activity of an antimicrobial drug

by Lorenzo Ciotti
Role of pollution in antibiotic resistance

Over the years, antibiotic resistance has become increasingly important, especially with regard to bacterial strains whose sensitivity to certain drugs seemed undisputed, for example Salmonella and chloramphenicol. One of the main causes of this trend is improper use of antibiotics.

An important and current example of antibiotic resistance is methicillin resistance related to staphylococci and, in particular, Staphylococcus aureus. Methicillin-resistant staphylococci represent a major cause of nosocomial infections.

These bacteria have a protein, called PBP 2a, which has low affinity to all β-lactam antibiotics, i.e. penicillins and cephalosporins, compared to the normal form of the PBP 2 protein. Another important example of antibiotic resistance is the vancomycin resistance of enterococci.

Vancomycin is a high molecular weight molecule that prevents the production of peptidoglycan, the main component of the bacterial cell wall. This antibiotic resistance involves the acquisition of a transposon, consisting of nine genes.

One of the proteins encoded by these genes, called Van S, is located outside the bacterial cell and, in the presence of vancomycin, is able to bind to it, resulting in the birth of an intracellular signal. This signal causes the production of other proteins which, through a complex mechanism, replace the target of vancomycin with another molecule that the antibiotic is not able to recognize.

In this way, Vancomycin is made totally inactive.

Role of pollution in antibiotic resistance

The Role of pollution on the selection of antibiotic resistance and bacterial pathogens in the environment study, published on the Current opinion in microbiology, said: "There is evidence that human activity causes pollution that contributes to an enhanced selection of bacterial pathogens in the environment.

In this review, we consider how environmental pollution can favor the selection of bacterial pathogens in the environment. We specifically discuss pollutants released into the environment. by human activities (mainly human waste) that are associated with the selection for genetic features in environmental bacterial populations that lead to the emergence of bacterial pathogens.

Finally, we also identify key pollutants that are associated with antibiotic resistance and discuss possibilities of how to prevent their release into the environment."