A Graph-Based Algorithm to Determine Protein Structure from Cryo-EM Data
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چکیده
OF THE THESIS A Graph-Based Algorithm to Determine Protein Structure from Cryo-EM Data by Stephen Schuh Master of Science in Computer Science Washington University in St. Louis, 2011 Research Advisor: Professor Tao Ju Cryo-electron microscopy (cryo-EM) provides 3D density maps of proteins, but these maps do not have sufficiently high resolution to directly yield atomic-scale models. Previous work has shown that features known as secondary structures can be located in these density maps. A second source of information about proteins is sequence analysis, which predicts locations of secondary structures along the protein sequence but does not provide any information about the 3D shape of the protein. This thesis presents a graph-based algorithm to find the correspondence between the secondary structures in the density map and sequence. This provides an ordering of secondary structures in the 3D density map, which can be used in building an atomic-scale model of the protein.
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