What effect does nitric oxide–derived reactive nitrogen species have on bacterial biofilms?

What effect does nitric oxide–derived reactive nitrogen species have on bacterial biofilms?

• A. Disperses biofilms
• B. Strengthens biofilms
• C. Has no effect on biofilms
• D. Increases biofilm thickness

Answer: (A)

Low levels of nitric oxide–derived reactive nitrogen species act as signaling cues that trigger biofilm dispersal. In many bacteria, NO influences the cyclic-di-GMP signaling network, a key regulator of the switch between a sessile biofilm lifestyle and a motile planktonic state. When NO is present, enzymes that synthesize or degrade cyclic-di-GMP shift the balance to lower levels, reducing production of the biofilm matrix and increasing motility. This promotes detachment from the surface and transition to a free-swimming form. Nitrosylation or modification of proteins involved in matrix maintenance can further enhance this dispersal effect. In the context of infection, host immune cells generate NO, contributing to the disassembly of biofilms and making bacteria more susceptible to antimicrobial treatment. Thus, nitric oxide–derived reactive nitrogen species promote biofilm dispersal.

Low levels of nitric oxide–derived reactive nitrogen species act as signaling cues that trigger biofilm dispersal. In many bacteria, NO influences the cyclic-di-GMP signaling network, a key regulator of the switch between a sessile biofilm lifestyle and a motile planktonic state. When NO is present, enzymes that synthesize or degrade cyclic-di-GMP shift the balance to lower levels, reducing production of the biofilm matrix and increasing motility. This promotes detachment from the surface and transition to a free-swimming form. Nitrosylation or modification of proteins involved in matrix maintenance can further enhance this dispersal effect. In the context of infection, host immune cells generate NO, contributing to the disassembly of biofilms and making bacteria more susceptible to antimicrobial treatment. Thus, nitric oxide–derived reactive nitrogen species promote biofilm dispersal.