Microbial Cell Membrane Disruption by Nitric Oxide Release

Microbial cell membrane disruption by nitric oxide (NO) release refers to a mechanism where NO, a reactive nitrogen species, damages or permeabilizes the membranes of microbial cells. This process compromises membrane integrity, leading to cell lysis or death. The approach is of interest for antimicrobial therapy because it targets fundamental structural features of microbes and can reduce the likelihood of resistance development. When released in proximity to microbial cells, NO can react with membrane lipids and proteins, causing nitrosative stress, induce lipid peroxidation and disrupt the lipid bilayer structure, and increase membrane permeability and depolarize the bacterial cell envelope. The disruption leads to leakage of cytoplasmic contents and loss of essential gradients (e.g., proton motive force), resulting in rapid bacterial death. Strategies that deliver exogenous NO or trigger its release at infection sites are being explored for antimicrobial applications. Bacterial membranes are rich in negatively charged phospholipids, making them more susceptible to reactive species like NO. Mammalian outer membranes contain neutral lipids providing some protection.

Physical/chemical damage via nitrosative stress; increased permeability