1opf
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THE STRUCTURE OF OMPF PORIN IN A TETRAGONAL CRYSTAL FORM
OverviewOverview
BACKGROUND: OmpF porin is a trimeric integral membrane protein responsible, for the passive transport of small hydrophilic molecules, such as, nutrients and waste products, across the outer membrane of Escherichia, coli. Very few membrane proteins have been crystallized in three, dimensions, yet this stable protein can be obtained in several crystal, forms. Comparison of the structures of the same membrane protein in two, different packing environments is of major interest, because it allows us, to explore the integrity of the structure outside the natural membrane, environment. RESULTS: The structure of OmpF porin in a tetragonal crystal, form with two trimers per asymmetric unit has been determined at 3.2 A, resolution and compared with that obtained previously in a trigonal, crystal form. The lattice contacts involve only polar atoms, whereas, extensive hydrophobic protein-protein interactions were found in the, trigonal lattice. The trimer structure is virtually identical in both., CONCLUSIONS: Our comparison reveals that the overall structure of OmpF is, not influenced by crystal lattice constraints and, thus, presumably bears, close resemblance to the in vivo structure. The tetragonal crystal, structure has provided the starting model for the phasing of neutron, diffraction data obtained from this crystal form, as described in an, accompanying article.
About this StructureAbout this Structure
1OPF is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
ReferenceReference
The structure of OmpF porin in a tetragonal crystal form., Cowan SW, Garavito RM, Jansonius JN, Jenkins JA, Karlsson R, Konig N, Pai EF, Pauptit RA, Rizkallah PJ, Rosenbusch JP, et al., Structure. 1995 Oct 15;3(10):1041-50. PMID:8589999
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