Metal nanoparticles (NPs) are promising antibacterial agents due to their ability to kill bacteria through various mechanisms, including the production of reactive oxygen species (ROS), cation release, biomolecule damage, ATP depletion, and membrane interaction. This review discusses the mechanisms of antibacterial action of different metal NPs, as well as their effects on gene and protein regulation (transcriptomic and proteomic profiles). Gram-positive bacteria are generally more resistant to NP mechanisms of action than Gram-negative bacteria, which have a thinner peptidoglycan layer and an additional outer membrane. The cell wall structure and charge play a significant role in NP interactions, with Gram-negative bacteria being more susceptible due to their negatively charged cell walls. The antibacterial activity of NPs is influenced by factors such as size, shape, charge, and the presence of capping agents. Positively charged NPs are more effective due to electrostatic attraction to the negatively charged bacterial cell wall. The release of ions from NPs is a key factor in their toxicity, with higher ion release leading to greater antibacterial activity. The interaction of NPs with bacterial cells can lead to membrane damage, cell lysis, and the production of ROS, which can cause oxidative stress and cell death. The antioxidant glutathione (GSH) is involved in protecting cells from oxidative stress, but its depletion can lead to increased cellular damage. NPs can also interact with intra/extracellular compounds and DNA, affecting bacterial growth and survival. The global gene and protein regulation upon exposure to NPs indicates that bacteria adapt to NP-containing environments by altering their gene expression and protein profiles. The antibacterial activity of NPs is influenced by various factors, including the type of metal, size, shape, and surface chemistry of the NPs. The interaction of NPs with bacterial cells can lead to cell death through multiple mechanisms, including membrane disruption, ROS production, and DNA damage. The study highlights the importance of understanding the mechanisms of NP antibacterial activity to develop effective and safe nanomedicine applications.Metal nanoparticles (NPs) are promising antibacterial agents due to their ability to kill bacteria through various mechanisms, including the production of reactive oxygen species (ROS), cation release, biomolecule damage, ATP depletion, and membrane interaction. This review discusses the mechanisms of antibacterial action of different metal NPs, as well as their effects on gene and protein regulation (transcriptomic and proteomic profiles). Gram-positive bacteria are generally more resistant to NP mechanisms of action than Gram-negative bacteria, which have a thinner peptidoglycan layer and an additional outer membrane. The cell wall structure and charge play a significant role in NP interactions, with Gram-negative bacteria being more susceptible due to their negatively charged cell walls. The antibacterial activity of NPs is influenced by factors such as size, shape, charge, and the presence of capping agents. Positively charged NPs are more effective due to electrostatic attraction to the negatively charged bacterial cell wall. The release of ions from NPs is a key factor in their toxicity, with higher ion release leading to greater antibacterial activity. The interaction of NPs with bacterial cells can lead to membrane damage, cell lysis, and the production of ROS, which can cause oxidative stress and cell death. The antioxidant glutathione (GSH) is involved in protecting cells from oxidative stress, but its depletion can lead to increased cellular damage. NPs can also interact with intra/extracellular compounds and DNA, affecting bacterial growth and survival. The global gene and protein regulation upon exposure to NPs indicates that bacteria adapt to NP-containing environments by altering their gene expression and protein profiles. The antibacterial activity of NPs is influenced by various factors, including the type of metal, size, shape, and surface chemistry of the NPs. The interaction of NPs with bacterial cells can lead to cell death through multiple mechanisms, including membrane disruption, ROS production, and DNA damage. The study highlights the importance of understanding the mechanisms of NP antibacterial activity to develop effective and safe nanomedicine applications.