Concept explainers
LPS is synthesized in the cytoplasm and then transported to and inserted into the outer membrane. This is complicated by the amphipathic nature of LPS. Recently two different laboratories reported their studies on seven LPS transport proteins (Lpt proteins) that move LPS from the cytoplasm into the outer membrane. Several of the Lpt proteins fold to form a structure called a β-jelly roll, which can be described as being “greasy.” Other Lpt proteins fold to form a β-barrel. Hypothesize how each fold might interact with an LPS molecule. Why would two different types of proteins be needed?
Read the original papers. Dong, H., et al. 2014. Structural basis for outer membrane lipopolysaccharide insertion. Nature 511:52; Qiao, S., 2014. Structural basis for lipopolysaccharide insertion in the outer membrane. Nature 511:108.
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Prescott's Microbiology
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