Nourseothricin

Chemical structure of Nourseothricin

Nourseothricin is a broad-spectrum antibiotic complex that belongs to the class of streptothricins. It is produced by the actinomycete bacterium Streptomyces noursei. Nourseothricin is primarily used in molecular biology as a selective agent for cells that have been transformed with a gene conferring resistance to this antibiotic.

Mechanism of Action

Nourseothricin functions by inhibiting protein synthesis in susceptible organisms. It binds to the 30S subunit of the bacterial ribosome, interfering with the initiation of protein synthesis and causing miscoding during translation. This action ultimately leads to the death of the bacterial cell.

Applications in Molecular Biology

In molecular biology, nourseothricin is used as a selective agent in genetic engineering. Cells that have been transformed with a plasmid containing the nat1 gene, which confers resistance to nourseothricin, can be selected by growing them in media containing the antibiotic. This allows researchers to identify and propagate cells that have successfully incorporated the desired genetic material.

Resistance

Resistance to nourseothricin is conferred by the nat1 gene, which encodes an enzyme that acetylates nourseothricin, rendering it inactive. This gene is often used as a selectable marker in genetic engineering experiments.

Safety and Handling

Nourseothricin should be handled with care in the laboratory setting. It is important to follow appropriate safety protocols, including the use of personal protective equipment, when working with this antibiotic.

Related Pages

• Streptothricin
• Streptomyces noursei
• Antibiotic resistance
• Selectable marker