Antibiotic Resistance Introduction
Antibiotic resistance occurs when bacteria evolve mechanisms to withstand drugs designed to kill them, leading to treatment failure, persisting infections, and the spread of resistant strains.
Resistance Through Mutation
Random mutations can provide bacteria with resistance. These mutations may alter the drug's target site, diminish drug uptake, or increase its export. Such changes can render antibiotics ineffective.
Enzymatic Drug Inactivation
Bacteria can produce enzymes that chemically degrade antibiotics. For instance, beta-lactamases break down penicillins and cephalosporins, neutralizing their bactericidal effect.
Efflux Pumps Expulsion
Efflux pumps are proteins that bacteria use to eject antibiotics before they can take effect. They can act on multiple antibiotics, contributing to multidrug resistance.
Altered Target Sites
Bacteria may modify the antibiotic's binding site, reducing drug affinity. Methicillin-resistant Staphylococcus aureus (MRSA) changes its penicillin-binding proteins to evade the drug's action.
Resistance Gene Transfer
Bacterial plasmids can carry resistance genes between species. This horizontal gene transfer can quickly spread resistance across bacterial populations and diverse species.
Antibiotic Resistance Misconceptions
Contrary to common belief, it's not our bodies that become resistant to antibiotics, but the bacteria themselves. Misuse and overuse of antibiotics accelerate this natural evolutionary process.