The L2 loop peptide of RecA stiffens and restricts base motions of single‐stranded DNA similar to the intact protein 1

FEBS Letters

Nordén, Bengt³  Selmane, Tassadite¹  Camerini-Otero, Daniel R.²  Voloshin, Oleg N.²  Wittung-Stafshede, Pernilla³  Takahashi, Masayuki¹  Maraboeuf, Fabrice¹ 

[1] Unité Mixte de Recherche 216, Institut Curie and CNRS, F-91405 Orsay, France;Genetics and Biochemistry Branch, NIDDK, National Institutes of Health, Bethesda, MD 29892 USA;Department of Physical Chemistry, Chalmers University of Technology, S-41296 Gothenburg, Sweden

关键词: RecA protein;    Homologous recombination;    DNA binding;    Peptide;    DNA base motion;    LD;    linear dichroism;    CD;    circular dichroism;    Poly(dϵA);    poly(1;    N6-etheno-deoxyadenosine;   

DOI  :  10.1016/S0014-5793(99)00181-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The L2 loop in the RecA protein is the catalytic center for DNA strand exchange. Here we investigate the DNA binding properties of the L2 loop peptide using optical spectroscopy with polarized light. Both fluorescence intensity and anisotropy of an etheno-modified poly(dA) increase upon peptide binding, indicate that the base motions of single-stranded DNA are restricted in the complex. In agreement with this conclusion, the peptide-poly(dT) complex exhibits a significant linear dichroism signal. The peptide is also found to modify the structure of double-stranded DNA, but does not denature it. It is inferred that strand separation may not be required for the formation of a joint molecule.

【 授权许可】

Unknown