Lipopolysaccharide transport system (Lpt)

The lipopolysaccharide transport system (Lpt) is a multi-protein complex found in Gram-negative bacteria that mediates the essential process by which newly synthesized lipopolysaccharides are transported from their site of synthesis at the inner membrane across the periplasmic space and inserted into the outer leaflet of the outer membrane. This process involves several key proteins—most notably those encoded by lpt genes—including an ATP-binding cassette transporter at the inner membrane (LptBFGC), periplasmic bridge proteins like LptA, and an insertion complex at the outer membrane (LptDE). Proper function ensures maintenance of bacterial envelope integrity and resistance against environmental threats including antibiotics. Disruption or inhibition leads rapidly to loss of viability due to compromised barrier function. Because it is unique and essential in pathogenic bacteria but absent from humans, it represents an attractive target for novel antibacterial therapies aimed at combating multidrug-resistant infections.

Other names

Lpt transporterLipopolysaccharide export systemLipopolysaccharide transport machinery

Drugs targeting this molecule would inhibit one or more components of the Lpt machinery, blocking export of lipopolysaccharides and compromising bacterial outer membrane integrity—leading to cell death or increased susceptibility to other antibiotics