Question

Which narrow-spectrum antibiotic, characterized by its bactericidal properties, functions by inhibiting DNA replication? Importantly, this antibiotic is not commonly found in Gram-negative bacteria. Could you provide additional information regarding the specific antibiotic, its mechanism of action, and any notable characteristics associated with its use?

Answer 1

Nalidixic acid, a narrow-spectrum antibiotic in the quinolone family, inhibits bacterial DNA gyrase thus blocking DNA replication, and is characterized by its bactericidal properties.

Step-by-step explanation:

The narrow-spectrum antibiotic known for its bactericidal properties and its function of inhibiting DNA replication in bacteria is nalidixic acid, a member of the quinolone family. This antibiotic was originally discovered as a byproduct during the synthesis of an antimalarial drug and operates by selectively inhibiting the activity of bacterial DNA gyrase, an enzyme vital for DNA replication. This mechanism of action provides selective toxicity, targeting bacterial cells without affecting human cells. Nalidixic acid does not have much efficacy against Gram-negative bacteria; it has been superseded by more potent fluoroquinolones like ciprofloxacin and levofloxacin, which are broad-spectrum and can treat a wide range of infections. It is important to use such antibiotics judiciously to avoid side effects and the development of antibiotic resistance.