title: Prediction by a neural network of outer membrane beta-strand protein topology.
abstract: An artificial neural network (NN) was trained to predict the topology of bacterial outer membrane (OM) beta-strand proteins. Specifically, the NN predicts the z-coordinate of Calpha atoms in a coordinate frame with the outer membrane in the xy-plane, such that low z-values indicate periplasmic turns, medium z-values indicate transmembrane beta-strands, and high z-values indicate extracellular loops. To obtain a training set, seven OM proteins (porins) with structures known to high resolution were aligned with their pores along the z-axis. The relationship between Calpha z-values and topology was thereby established. To predict the topology of other OM proteins, all seven porins were used for the training set. Z-values (topologies) were predicted for two porins with hitherto unknown structure and for OM proteins not belonging to the porin family, all with insignificant sequence homology to the training set. The results of topology prediction compare favorably with experimental topology data.
authors.affiliation: Universität Konstanz, Fakultät für Biologie (M656), Germany. Kay.Diederichs@uni-konstanz
authors.forename: K
authors.initials: K
authors.lastname: Diederichs
authors.forename: J
authors.initials: J
authors.lastname: Freigang
authors.forename: S
authors.initials: S
authors.lastname: Umhau
authors.forename: K
authors.initials: K
authors.lastname: Zeth
authors.forename: J
authors.initials: J
authors.lastname: Breed
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry*; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000737:chemistry; D004926:Escherichia coli / Q000737:chemistry; D029968:Escherichia coli Proteins; D019741:Haemophilus influenzae type b / Q000737:chemistry; D006801:Humans; D008433:Mathematics; D016571:Neural Networks, Computer; D018272:Porins / Q000737:chemistry; D017433:Protein Structure, Secondary; D011956:Receptors, Cell Surface; D011991:Receptors, Virus / Q000737:chemistry; D012243:Rhodopsin / Q000737:chemistry
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C050900:FhuA protein, E coli; C115885:Omp32 protein, bacteria; D018272:Porins; D011956:Receptors, Cell Surface; D011991:Receptors, Virus; C029489:enterobactin receptor; C078167:OMPA outer membrane proteins; D012243:Rhodopsin