PMID:10047484

From EcoliWiki
Jump to navigation Jump to search
Citation

Hörtnagel, K, Voloshin, ON, Kinal, HH, Ma, N, Schaffer-Judge, C and Camerini-Otero, RD (1999) Saturation mutagenesis of the E. coli RecA loop L2 homologous DNA pairing region reveals residues essential for recombination and recombinational repair. J. Mol. Biol. 286:1097-106

Abstract

The disordered mobile loop L2 of the Escherichia coli RecA protein is known to play a central role in DNA binding and pairing. To investigate the local chemical environment in relation to function we performed saturation mutagenesis of the loop L2 region (amino acid positions 193-212) using a site-directed mutagenesis procedure, and determined the recombinational proficiency of the 380 mutants using genetic assays for homologous recombination and recombinational repair. Residues Asn193, Gln194, Arg196, Glu207, Thr209, Gly211, and Gly212 were identified as stringently required for recombinational events in bacterial cells. In addition, our findings suggest the involvement of loop L2 in the ATPase activity of RecA, and a role for residues Gln194, Arg196, Lys198 and Thr209 in the DNA-dependent hydrolysis of ATP. Finally, since 20 residue peptides that comprise this region can pair homologous DNAs by forming filamentous beta-structures, we propose how the information from the mutant analysis might facilitate the use of a simplified amino acid alphabet to design beta-structure forming L2 peptides with improved RecA-like activities.

Links

PubMed Online version:10.1006/jmbi.1998.2515

Keywords

DNA Repair; Escherichia coli/genetics; Models, Molecular; Mutagenesis, Site-Directed; Nucleic Acid Conformation; Protein Conformation; Rec A Recombinases/chemistry; Rec A Recombinases/genetics; Rec A Recombinases/metabolism; Recombination, Genetic

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.