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Updated: Aug 24, 2026

Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
Crystallization and preliminary X-ray crystallographic analyses of EcoO109I and its complex with DNA
Tsuyoshi Imasaki1, Hiroshi Hashimoto, Toshiyuki Shimizu
1Graduate School of Integrated Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.
Abstract:
EcoO109I is a type II restriction endonuclease that recognizes seven base pairs of the degenerate and discontinuous sequence RGGNCCY. The enzyme and its complex with DNA were successfully crystallized by the hanging-drop vapour-diffusion method using polyethylene glycols as precipitants. The crystal of EcoO109I belongs to space group I4, with unit-cell parameters a = b = 175.5, c = 44.6 angstoms, and that of the DNA complex belongs to space group P2(1)2(1)2(1), with unit-cell parameters a = 49.1, b = 71.8, c = 203.2 angstroms. Full sets of X-ray diffraction data from the enzyme and its complex with DNA were collected to 2.4 and 1.9 angstroms resolution, respectively.
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