Why is it in the news?

• Researchers have made a significant breakthrough in antibiotic discovery with the identification of a new class named ‘Zosurabalpin.’
• This antibiotic is specifically designed to combat the drug-resistant bacterium, Acinetobacter baumannii, particularly the carbapenem-resistant strain known as CRAB.

More about the news

• Zosurabalpin is characterized as an antibody demonstrating efficacy against conditions induced by CRAB, such as pneumonia and sepsis, particularly observed in mouse models.
• The antibiotic is derived from a tethered macrocyclic peptide (MCP), a class of molecules.
• Scientists identified this MCP for its selective lethality towards A. baumannii.
• Further optimization of the MCP was undertaken to enhance its efficacy and tolerability, leading to the creation of Zosurabalpin.
• Zosurabalpin operates through a previously unknown mode of action.
• It inhibits the transport of lipopolysaccharide (LPS) molecules within the bacterium. This inhibition is achieved by blocking a complex of proteins responsible for LPS transport.
• LPS transport is crucial for the construction of the outer-membrane structure in Gram-negative bacteria.
• The blocking of LPS transport disrupts the normal functioning of the bacterium, leading to an abnormal accumulation of LPS within the bacterial cell. The abnormal build-up of LPS disrupts the bacterium’s cellular functions, ultimately causing its death.
• Zosurabalpin has demonstrated high efficacy against a wide range of clinically tested samples of CRAB in laboratory settings.
• This promising efficacy holds potential for addressing the challenge posed by drug-resistant strains of Acinetobacter baumannii.