The L2 Loop Peptide of recA Stiffens and restricts Base Motions of Single-stranded DNA Similar to Intact Protein
Artikel i vetenskaplig tidskrift, 1999

The L2 loop in the RecA protein is the catalytic center for DNA strand exchange, Here we investigate the DMA 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.

DNA binding


homologous recombination

RecA protein

DNA base motion


T. Selmane

Pernilla Wittung Stafshede

Institutionen för fysikalisk kemi

F. Maraboeuf

O. Voloshin

Bengt Nordén

Institutionen för fysikalisk kemi

D. Camerini-Otero

M. Takahashi

FEBS Letters

0014-5793 (ISSN)

Vol. 446 30-34


Nanovetenskap och nanoteknik


Livsvetenskaper och teknik



Fysikalisk kemi


Grundläggande vetenskaper