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Lipopolysaccharide is transported to the cell surface by a membrane-to-membrane protein bridge.

ABSTRACT: Gram-negative bacteria have an outer membrane that serves as a barrier to noxious agents in the environment. This protective function is dependent on lipopolysaccharide, a large glycolipid located in the outer leaflet of the outer membrane. Lipopolysaccharide is synthesized at the cytoplasmic membrane and must be transported to the cell surface. To understand this transport process, we reconstituted membrane-to-membrane movement of lipopolysaccharide by incorporating purified inner and outer membrane transport complexes into separate proteoliposomes. Transport involved stable association between the inner and outer membrane proteoliposomes. Our results support a model in which lipopolysaccharide molecules are pushed one after the other in a PEZ dispenser-like manner across a protein bridge that connects the inner and outer membranes.

SUBMITTER: Sherman DJ

PROVIDER: S-EPMC5858563 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Lipopolysaccharide is transported to the cell surface by a membrane-to-membrane protein bridge.

Sherman David J DJ Xie Ran R Taylor Rebecca J RJ George Alexander H AH Okuda Suguru S Foster Peter J PJ Needleman Daniel J DJ Kahne Daniel D

Science (New York, N.Y.) 20180201 6377

Gram-negative bacteria have an outer membrane that serves as a barrier to noxious agents in the environment. This protective function is dependent on lipopolysaccharide, a large glycolipid located in the outer leaflet of the outer membrane. Lipopolysaccharide is synthesized at the cytoplasmic membrane and must be transported to the cell surface. To understand this transport process, we reconstituted membrane-to-membrane movement of lipopolysaccharide by incorporating purified inner and outer mem ...[more]

PMID: 29449493

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