Glycylcycline

Glycylcycline is a class of antibiotics that was first discovered in the late 20th century. They are derived from tetracycline antibiotics, but have been chemically modified to overcome the common resistance mechanisms that render many tetracyclines ineffective.

History

The first glycylcycline, tigecycline, was approved by the FDA in 2005. It was developed in response to the increasing prevalence of antibiotic resistance, particularly among Gram-negative bacteria.

Mechanism of Action

Glycylcyclines work by binding to the 30S ribosomal subunit of bacteria, preventing the attachment of aminoacyl-tRNA and thereby inhibiting protein synthesis. This is the same mechanism of action as tetracyclines. However, glycylcyclines have been modified to avoid the two main resistance mechanisms to tetracyclines: efflux pumping and ribosomal protection.

Clinical Use

Glycylcyclines are broad-spectrum antibiotics, effective against a wide range of Gram-positive and Gram-negative bacteria, including many multi-drug resistant strains. They are often used as a last-resort treatment when other antibiotics have failed.

Side Effects

Common side effects of glycylcyclines include nausea, vomiting, and diarrhea. More serious side effects can include damage to the liver and an increased risk of death, particularly in patients with severe infections.

Future Developments

Research is ongoing into the development of new glycylcyclines with improved efficacy and safety profiles. These new drugs could play a crucial role in the fight against antibiotic resistance.