title: A combined kinetic push and thermodynamic pull as driving forces for outer membrane protein sorting and folding in bacteria.
abstract: In vitro folding studies of outer membrane beta-barrels have been invaluable in revealing the lipid effects on folding rates and efficiencies as well as folding free energies. Here, the biophysical results are summarized, and these kinetic and thermodynamic findings are considered in terms of the requirements for folding in the context of the cellular environment. Because the periplasm lacks an external energy source the only driving forces for sorting and folding available within this compartment are binding or folding free energies and their associated rates. These values define functions for periplasmic chaperones and suggest a biophysical mechanism for the BAM complex.
authors.affiliation: Department of Biophysics, Johns Hopkins University, Baltimore, MD, USA karen.fleming@jhu.edu.
authors.forename: Karen G
authors.initials: KG
authors.lastname: Fleming
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D055592:Biophysical Phenomena; D007700:Kinetics; D008954:Models, Biological; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000378:metabolism; D019897:Periplasm / Q000378:metabolism; D017510:Protein Folding; D013816:Thermodynamics
chemical_list: D001425:Bacterial Outer Membrane Proteins; D018832:Molecular Chaperones
keywords: chaperone; driving forces; membrane protein; outer membrane protein; protein folding; protein sorting