Abstract
Cryo-electron microscopy (Cryo-EM) is a technique that produces three-dimensional density maps of large protein complexes and enables the study of the interactions and structures of those molecules. Identifying the secondary structures (α-helices and β-sheets) located in proteins using density maps is vital in identifying and matching the backbone of the protein with the cryo-EM density map. The β-barrel is a unique β-sheet structure commonly found in proteins, such as membranes and lipocalins. We present a new approach utilizing a genetic algorithm and ray tracing to automatically identify and extract β-barrels from cryo-EM density maps. This approach was tested using ten simulated density maps at 9 Å resolution and six experimental density maps at various resolutions. The results suggest that our approach is capable of performing automatic detection and extraction of the β-barrels from medium resolution cryo-EM density maps.
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References
Adrian, M., Dubochet, J., Lepault, J., McDowall, A.W.: Cryo-electron microscopy of viruses. Nature 308, 32–36 (1984)
Kühlbrandt, W.: Cryo-EM enters a new era. eLife 3, e03678 (2014)
Zhou, Z.H.: Atomic resolution cryo electron microscopy of macromolecular complexes. Adv. Protein Chem. Struct. Biol. 82, 1–35 (2011)
Lawson, C.L., Baker, M.L., Best, C., Bi, C., Dougherty, M., Feng, P., van Ginkel, G., Devkota, B., Lagerstedt, I., Ludtke, S.J., Newman, R.H., Oldfield, T.J., Rees, I., Sahni, G., Sala, R., Velankar, S., Warren, J., Westbrook, J.D., Henrick, K., Kleywegt, G.J., Berman, H.M., Chiu, W.: EMDataBank.org: unified data resource for CryoEM. Nucleic Acids Res. 39, D456–D464 (2011)
Al Nasr, K., Sun, W., He, J.: Structure prediction for the helical skeletons detected from the low resolution protein density map. BMC Bioinf. 11, S44 (2010)
Baker, M.L., Ju, T., Chiu, W.: Identification of secondary structure elements in intermediate-resolution density maps. Struct. Lond. Engl. 1993(15), 7–19 (2007)
Si, D., Ji, S., Nasr, K.A., He, J.: A machine learning approach for the identification of protein secondary structure elements from electron cryo-microscopy density maps. Biopolymers 97, 698–708 (2012)
Si, D., He, J.: Combining image processing and modeling to generate traces of beta-strands from cryo-EM density images of beta-barrels. In: 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, pp. 3941–3944 (2014)
Rusu, M., Wriggers, W.: Evolutionary bidirectional expansion for the tracing of alpha helices in cryo-electron microscopy reconstructions. J. Struct. Biol. 177, 410–419 (2012)
Jiang, W., Baker, M.L., Ludtke, S.J., Chiu, W.: Bridging the information gap: computational tools for intermediate resolution structure interpretation. J. Mol. Biol. 308, 1033–1044 (2001)
Si, D., He, J.: Tracing beta strands using StrandTwister from cryo-EM density maps at medium resolutions. Struct. Lond. Engl. 1993(22), 1665–1676 (2014)
Li, R., Si, D., Zeng, T., Ji, S., He, J.: Deep convolutional neural networks for detecting secondary structures in protein density maps from cryo-electron microscopy. In: 2016 IEEE International Conference on Bioinformatics and Biomedicine (BIBM), pp. 41–46 (2016)
Dal Palù, A., He, J., Pontelli, E., Lu, Y.: Identification of alpha-helices from low resolution protein density maps. In: Computational Systems Bioinformatics Conference, pp. 89–98 (2006)
Si, D., He, J.: Modeling beta-traces for beta-barrels from cryo-EM density maps. Biomed. Res. Int. 2017, 1793213 (2017)
Si, D., He, J.: Beta-sheet detection and representation from medium resolution cryo-EM density maps. In: Proceedings of the International Conference on Bioinformatics, Computational Biology and Biomedical Informatics, pp. 764:764–764:770. ACM (2013)
Si, D.: Automatic detection of beta-barrel from medium resolution Cryo-Em density maps. In: Proceedings of the 7th ACM International Conference on Bioinformatics, Computational Biology, and Health Informatics, pp. 156–164. ACM, New York (2016)
Wimley, W.C.: The versatile β-barrel membrane protein. Curr. Opin. Struct. Biol. 13, 404–411 (2003)
Flower, D.R.: The lipocalin protein family: structure and function. Biochem. J. 318, 1–14 (1996)
Pettersen, E.F., Goddard, T.D., Huang, C.C., Couch, G.S., Greenblatt, D.M., Meng, E.C., Ferrin, T.E.: UCSF Chimera–a visualization system for exploratory research and analysis. J. Comput. Chem. 25, 1605–1612 (2004)
Baker, M.L., Baker, M.R., Hryc, C.F., Ju, T., Chiu, W.: Gorgon and pathwalking: macromolecular modeling tools for subnanometer resolution density maps. Biopolymers 97, 655–668 (2012)
Fraser, A.S., Fraser, A.S.: Simulation of genetic systems by automatic digital computers I. Introduction. Aust. J. Biol. Sci. 10, 484–491 (1957)
Holland, J.H.: Adaptation in Natural and Artificial Systems: An Introductory Analysis with Applications to Biology, Control and Artificial Intelligence. MIT Press, Cambridge (1992)
Zhao, X., Gao, X.-S., Hu, Z.-C.: Evolutionary programming based on non-uniform mutation. Appl. Math. Comput. 192, 1–11 (2007)
Goldstein, R.A., Nagel, R.: 3-D visual simulation. Trans. Soc. Comput. Simul. 16, 25–31 (1971)
Altman, D.G., Bland, J.M.: Statistics notes: diagnostic tests 1: sensitivity and specificity. BMJ 308, 1552 (1994)
Ludtke, S.J., Baldwin, P.R., Chiu, W.: EMAN: semiautomated software for high-resolution single-particle reconstructions. J. Struct. Biol. 128, 82–97 (1999)
Acknowledgement
This work was supported by the Graduate Research Award from the Computing and Software Systems division of University of Washington Bothell and the startup fund 74-0525.
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Ng, A., Si, D. (2017). Genetic Algorithm Based Beta-Barrel Detection for Medium Resolution Cryo-EM Density Maps. In: Cai, Z., Daescu, O., Li, M. (eds) Bioinformatics Research and Applications. ISBRA 2017. Lecture Notes in Computer Science(), vol 10330. Springer, Cham. https://doi.org/10.1007/978-3-319-59575-7_16
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DOI: https://doi.org/10.1007/978-3-319-59575-7_16
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