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An Iterative Bezier Method for Fitting Beta-sheet Component of a Cryo-EM Density Map.

ABSTRACT: Cryo-electron microscopy (Cryo-EM) is a powerful technique to produce 3-dimensional density maps for large molecular complexes. Although many atomic structures have been solved from cryo-EM density maps, it is challenging to derive atomic structures when the resolution of density maps is not sufficiently high. Geometrical shape representation of secondary structural components in a medium-resolution density map enhances modeling of atomic structures. We compare two methods in producing surface representation of the β-sheet component of a density map. Given a 3-dimensional volume of β-sheet that is segmented from a density map, the performance of a polynomial fitting was compared with that of an iterative Bézier fitting. The results suggest that the iterative Bézier fitting is more suitable for β-sheets, since it provides more accurate representation of the corners that are naturally twisted in a β-sheet.

SUBMITTER: Poteat M

PROVIDER: S-EPMC8329936 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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An Iterative Bézier Method for Fitting Beta-sheet Component of a Cryo-EM Density Map.

Poteat Michael M He Jing J

Molecular based mathematical biology 20170101 1

Cryo-electron microscopy (Cryo-EM) is a powerful technique to produce 3-dimensional density maps for large molecular complexes. Although many atomic structures have been solved from cryo-EM density maps, it is challenging to derive atomic structures when the resolution of density maps is not sufficiently high. Geometrical shape representation of secondary structural components in a medium-resolution density map enhances modeling of atomic structures. We compare two methods in producing surface r ...[more]

PMID: 34350231

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