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Polymorphic Protective Dps-DNA Co-Crystals by Cryo Electron Tomography and Small Angle X-Ray Scattering.

ABSTRACT: Rapid increase of intracellular synthesis of specific histone-like Dps protein that binds DNA to protect the genome against deleterious factors leads to in cellulo crystallization-one of the most curious processes in the area of life science at the moment. However, the actual structure of the Dps-DNA co-crystals remained uncertain in the details for more than two decades. Cryo-electron tomography and small-angle X-ray scattering revealed polymorphous modifications of the co-crystals depending on the buffer parameters. Two different types of the Dps-DNA co-crystals are formed in vitro: triclinic and cubic. Three-dimensional reconstruction revealed DNA and Dps molecules in cubic co-crystals, and the unit cell parameters of cubic lattice were determined consistently by both methods.

SUBMITTER: Kamyshinsky R

PROVIDER: S-EPMC7023142 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Polymorphic Protective Dps-DNA Co-Crystals by Cryo Electron Tomography and Small Angle X-Ray Scattering.

Kamyshinsky Roman R Chesnokov Yury Y Dadinova Liubov L Mozhaev Andrey A Orlov Ivan I Petoukhov Maxim M Orekhov Anton A Shtykova Eleonora E Vasiliev Alexander A

Biomolecules 20191226 1

Rapid increase of intracellular synthesis of specific histone-like Dps protein that binds DNA to protect the genome against deleterious factors leads to in cellulo crystallization-one of the most curious processes in the area of life science at the moment. However, the actual structure of the Dps-DNA co-crystals remained uncertain in the details for more than two decades. Cryo-electron tomography and small-angle X-ray scattering revealed polymorphous modifications of the co-crystals depending on ...[more]

PMID: 31888079

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