A joint research project based in Kumamoto University, Japan has developed a new, highly sensitive analytical method that can detect degraded β-lactam antibacterial agents used in the treatment of bacterial infections. With this method, researchers found that reactive sulfur species produced by bacteria degrade and inactivate β-lactam antibiotics.
Bacteria are different from animal cells in that their outer layer is covered with a rigid structure called a cell wall. β-lactam antimicrobial agents interfere with the processes that form the cell wall. This results in bacteria no longer being able to withstand their own internal pressure so they rupture and die. β-lactam antimicrobial agents are very potent because they selectively inhibit bacterial cell wall synthesis and have few side effects on hosts such as humans. These antimicrobial agents have a common structure called the β-lactam ring that is essential for inhibiting cell wall development. If this ring is degraded, the antimicrobial effect disappears.