Reactive nitrogen species described in this context can disperse biofilms, alter bacterial physiology, and reduce viability.

Reactive nitrogen species described in this context can disperse biofilms, alter bacterial physiology, and reduce viability.

• A. All three effects are observed
• B. Only disperses biofilms
• C. Only reduces viability
• D. Only alters physiology

Answer: (A)

Reactive nitrogen species can act as signaling molecules at low levels and as stressors at higher levels. In biofilms, nitric oxide often serves as a cue that triggers dispersion by changing regulatory networks and lowering the intracellular signals that keep cells attached, leading to detachment from the matrix and a shift to a planktonic lifestyle. At the same time, RNS can nitrosylate or oxidize proteins, lipids, and nucleic acids, altering regulatory pathways and cellular processes, so bacterial physiology is shifted in response to nitrosative stress. When exposure is stronger or prolonged, these reactive species cause direct damage that impairs essential functions, reducing viability. Taken together, reactive nitrogen species can disperse biofilms, alter bacterial physiology, and decrease viability, depending on concentration and exposure context.

Reactive nitrogen species can act as signaling molecules at low levels and as stressors at higher levels. In biofilms, nitric oxide often serves as a cue that triggers dispersion by changing regulatory networks and lowering the intracellular signals that keep cells attached, leading to detachment from the matrix and a shift to a planktonic lifestyle. At the same time, RNS can nitrosylate or oxidize proteins, lipids, and nucleic acids, altering regulatory pathways and cellular processes, so bacterial physiology is shifted in response to nitrosative stress. When exposure is stronger or prolonged, these reactive species cause direct damage that impairs essential functions, reducing viability. Taken together, reactive nitrogen species can disperse biofilms, alter bacterial physiology, and decrease viability, depending on concentration and exposure context.