Amino acid sequence homology among the major outer membrane proteins of Escherichia coli.

Analysis of amino acid sequences reported for the major outer membrane proteins of Escherichia coli, including the porins (OmpF, OmpC, and PhoE), the phage lambda receptor (LamB), and another protein (OmpA), revealed several regions of local homology that is statistically significant. The implications of this observation are discussed in relation to the evolutionary origins of these proteins, as well as to the mechanism of export of these proteins to the outer membrane.