CA Runs Increase DNA Flexibility in the Complex of λ Cro Protein with the OR3 Site

Yuri L. Lyubchenko, Lyuda S. Shlyakhtenko, Rodney E. Harrington, Rodney E. Harrington

Research output: Contribution to journalArticle

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The alternating pyrimidine–purine elements CA, CAC, and CACA are anisotropically flexible, as deduced from gel circularization assays on point mutations and single-base mismatches in the OR3 site of λ phage alone and in the specific complex with the Cro protein. These sequences evidently promote DNA bending in the specific binding region of the complex and may also facilitate overwinding in the central nonbinding region. Effects for CACA are exceptionally large and suggest that an alternative DNA structure may occur in this element.

Original languageEnglish (US)
Pages (from-to)4121-4127
Number of pages7
Issue number15
Publication statusPublished - Apr 1 1993


ASJC Scopus subject areas

  • Biochemistry

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