title: Models for the structure of outer-membrane proteins of Escherichia coli derived from raman spectroscopy and prediction methods.
abstract: The secondary structure of porin, maltoporin and OmpA protein reconstituted in lipid membranes is determined by Raman spectroscopy. The three proteins have similar structures consisting of 50 to 60% beta-strand, about 20% beta-turn, and less than 15% alpha-helix. Employing a method for structural prediction that accounts for amphipathic beta-strands, folding models are developed for porin and for the segment of OmpA protein incorporated into the membrane. In the model, the OmpA fragment consists of eight amphipathic membrane-spanning beta-strands that form a beta-barrel. Similarly, porin is folded into ten amphipathic membrane-spanning beta-strands that are located at the surface of the trimer towards the lipids and eight predominantly hydrophilic strands in the interior.
mesh_terms: D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins; D004926:Escherichia coli / Q000032:analysis*; D008954:Models, Biological; D009943:Organophosphorus Compounds; D018272:Porins; D011487:Protein Conformation; D011991:Receptors, Virus; D013059:Spectrum Analysis, Raman
chemical_list: D001425:Bacterial Outer Membrane Proteins; D009943:Organophosphorus Compounds; D018272:Porins; D011991:Receptors, Virus; C016532:maltoporins; C008705:octamethyl pyrophosphoramide