Abstract 1843 Bridge-like lipid transporters that build the outer membrane of Gram-negative bacteria

Gram-negative bacteria such as Escherichia coli have a multi-layered envelope that is delimited by two membranes. Their inner membrane, which surrounds the cytoplasm, is a phospholipid bilayer, while their outer membrane, which surrounds the aqueous periplasm, is asymmetrically built with phospholipids in its inner leaflet and lipopolysaccharides (LPS) in its outer leaflet. Since phospholipids and LPS are synthesized at the inner membrane, they must be transported across the cell envelope to build the outer membrane.