Lipopolysaccharides and divalent cations are involved in the formation of an assembly‐competent intermediate of outer‐membrane protein PhoE of E.coli.

摘要: To identify the requirements for biogenesis of outer-membrane proteins in Gram-negative bacteria, sorting and assembly trimeric, pore-forming protein PhoE was studied vitro. Purified lipopolysaccharide (LPS) combination with low amounts Triton X-100 divalent cations induced formation folded monomers. LPS deep-rough strains far less efficient monomers than wild-type was. These could be converted into heat-stable trimers upon addition outer membranes higher X-100. Trimerization precede insertion step. vitro data suggest that vivo proceeds sequentially by (i) a monomer interaction LPS; (ii) to sites membrane; (iii) trimerization; (iv) insertion.