A method for cryo-EM analysis of eukaryotic nucleosomes reconstituted in bacterial cells.

ABSTRACT: Conventional methods for preparing nucleosomes are time-consuming and technically demanding. In the present study, we extended the approach of generating nucleosomes in Escherichia coli by the co-expression of all four histones, allowing nucleosomes to be assembled in cells. The bacterially reconstituted nucleosomes can be readily prepared from the E. coli cells and directly subjected to cryo-EM single particle analysis. Using this method, we obtained a 2.56 Å nucleosome structure that is highly similar to a previously reported nucleosome crystal structure, validating the use of nucleosomes formed in E. coli for cryo-EM analysis. Unexpectedly, we also discovered a non-canonical nucleosome structure, in which two hexasomes are closely packed. This system provides a robu

SUBMITTER: Ho CH 

PROVIDER: S-EPMC12803842 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature