Native oligomers of three Pseudomonas aeruginosa outer membrane porin proteins and one Escherichia coli porin were demonstrated by using a chemical cross-linking technique. P. aeruginosa protein F, the major constitutive outer membrane porin, was cross-linked to dimers in outer membrane and whole-cell cross-linking experiments. Purified preparations of P. aeruginosa proteins F, D1 (glucose indu...

The Escherichia coli major outer membrane lipoprotein (Lpp) is released from the inner membrane into the periplasm as a complex with a carrier protein, LolA (p20), and is then specifically incorporated into the outer membrane. An outer membrane protein playing a critical role in Lpp incorporation was identified, and partial amino acid sequences of the protein, named LolB, were identical to thos...