Send to

Choose Destination
Proc Natl Acad Sci U S A. 2007 Apr 10;104(15):6400-5. Epub 2007 Apr 2.

Lipoprotein SmpA is a component of the YaeT complex that assembles outer membrane proteins in Escherichia coli.

Author information

Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.


A major role of the outer membrane (OM) of Gram-negative bacteria is to provide a protective permeability barrier for the cell, and proper maintenance of the OM is required for cellular viability. OM biogenesis requires the coordinated assembly of constituent lipids and proteins via dedicated OM assembly machineries. We have previously shown that, in Escherichia coli, the multicomponent YaeT complex is responsible for the assembly of OM beta-barrel proteins (OMPs). This complex contains the OMP YaeT and three OM lipoproteins. Here, we report another component of the YaeT complex, the OM lipoprotein small protein A (SmpA). Strains carrying loss-of-function mutations in smpA are viable but exhibit defects in OMP assembly. Biochemical experiments show that SmpA is involved in maintaining complex stability. Taken together, these experiments establish an important role for SmpA in both the structure and function of the YaeT complex.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center