Secondary structure of a channel-forming protein: porin from E. coli outer membranes.
Porin from Escherichia coli outer membranes has been analysed by high angle diffuse X-ray diffraction, and by attenuated total reflection infrared spectroscopy. These methods demonstrate independently that the majority of the polypeptide backbone is arranged in anti-parallel beta-pleated sheet structure. The average length of the beta-strands, which are oriented nearly normal to the membrane plane, is estimated to be 10-12 residues, independent of the method used. Although the details of strand arrangement (beta-barrels or stacked sheets) are not as yet known, porin represents the first transmembrane protein for which beta-structure has been established unequivocally.
Kleffel
B
B
Garavito
R M
RM
Baumeister
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W
Rosenbusch
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JP
D001425:Bacterial Outer Membrane Proteins; D004926:Escherichia coli / Q000032:analysis*; D018272:Porins; D011487:Protein Conformation; D013055:Spectrophotometry, Infrared; D014961:X-Ray Diffraction
D001425:Bacterial Outer Membrane Proteins; D018272:Porins