Suppression of homologous and homeologous recombination by the bacterial MutS2 protein

• Autores: Pinto, A.V.; Mathieu, A.; Marsin, S.; Veaute, X.; Ielpi, L.; Labigne, A.; Radicella, J.P.
• Año de publicación: 2005
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Mol. Cell 2005;17(1):113-120
• Materia: bacterial protein; DNA; protein MSH2; article; controlled study; DNA repair; DNA structure; enzyme activity; genetic variability; Helicobacter pylori; mismatch repair; nonhuman; protein purification; sequence homology; Adenosine Triphosphatases; Bacterial Proteins; Base Pair Mismatch; Binding Sites; DNA Repair; DNA, Bacterial; DNA-Binding Proteins; Helicobacter pylori; MutS DNA Mismatch-Binding Protein; Recombination, Genetic; Bacteria (microorganisms); Helicobacter; Helicobacter pylori
• Institución: Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales

In addition to their role in DNA repair, recombination events are associated with processes aimed at providing the genetic variability needed for adaptation and evolution of a population. In bacteria, recombination is involved in the appearance of new variants by allowing the incorporation of exogenous DNA or the reshuffling of endogenous sequences. Here we show that HpMutS2, a protein belonging to the MutS2 family in Helicobacter pylori, is not involved in mismatch repair but inhibits homologous and homeologous recombination. Disruption of HpmutS2 leads to an increased efficiency of exogenous DNA incorporation. HpMutS2 has a selective affinity for DNA structures mimicking recombination intermediates with no specificity for homoduplex DNA or mismatches. The purified protein has an ATPase activity stimulated by the same DNA structures. Finally, we show that HpMutS2 inhibits DNA strand exchange reactions in vitro. Thus, MutS2 proteins are candidates for controlling recombination and therefore genetic diversity in bacteria.
Fil:Ielpi, L. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Radicella, J.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.