Novel insights in the lipopolysaccharide transport system of Gram-negative bacteria

Abstract

The envelope of Gram negative bacteria consists of an inner membrane and an outer membrane, separated by the periplasm. The OM is an asymmetrical bilayer that contains phospholipids on its periplasmic side and LPS on its extracellular side. Although the LPS biosynthetic pathway has long been elucidated, less is known about the transport and assembly of LPS into the OM. Not long ago, the machinery involved in this process has been discovered. Since then, information regarding the machinery involved in LPS transport is accumulating. However, the exact mechanism of action of this machinery remains to be investigated. This review focuses on the most recent developments regarding the LPS transport system, with an emphasis on the components responsible for inserting LPS into the OM. In addition, this review will provide an example of the possible implications of new insights in the LPS transport system for the future, in the form of the development of novel Gram-negative treatment modalities that target the LPS transport system.