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Proteins required for lipopolysaccharide assembly in Escherichia coli form a transenvelope complex.

ABSTRACT: The viability of Gram-negative organisms is dependent on the proper placement of lipopolysaccharide (LPS) in the outer leaflet of its outer membrane. LPS is synthesized inside the cell and transported to the surface by seven essential lipopolysaccharide transport (Lpt) proteins. How these proteins cooperate to transport LPS is unknown. We show that these Lpt proteins can be found in a membrane fraction that contains inner and outer membranes and that they copurify. This constitutes the first evidence that the Lpt proteins form a transenvelope complex. We suggest that this protein bridge provides a route for LPS transport across the cell envelope.

SUBMITTER: Chng SS

PROVIDER: S-EPMC2880507 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Proteins required for lipopolysaccharide assembly in Escherichia coli form a transenvelope complex.

Chng Shu-Sin SS Gronenberg Luisa S LS Kahne Daniel D

Biochemistry 20100601 22

The viability of Gram-negative organisms is dependent on the proper placement of lipopolysaccharide (LPS) in the outer leaflet of its outer membrane. LPS is synthesized inside the cell and transported to the surface by seven essential lipopolysaccharide transport (Lpt) proteins. How these proteins cooperate to transport LPS is unknown. We show that these Lpt proteins can be found in a membrane fraction that contains inner and outer membranes and that they copurify. This constitutes the first evi ...[more]

PMID: 20446753

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