Person:
Toledo Arana, Alejandro

Profile Picture

Email Address

person.page.identifierURI

https://academica-e.unavarra.es/handle/2454/50078

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

Toledo Arana

First Name

Alejandro

person.page.departamento

Instituto de Agrobiotecnología (IdAB)

person.page.instituteName

ORCID

0000-0001-8148-6281

person.page.upna

5497

Name

Filters

20041
Reset filters

Settings

Start date: 2001 × End date: 2009 × Subject: Bap (biofilm associated protein) ×

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    PublicationOpen Access
    Calcium inhibits bap-dependent multicellular behavior in Staphylococcus aureus
    (American Society for Microbiology, 2004) Arrizubieta Balerdi, María Jesús; Toledo Arana, Alejandro; Amorena Zabalza, Beatriz; Penadés, José R.; Lasa Uzcudun, Íñigo; IdAB. Instituto de Agrobiotecnología / Agrobioteknologiako Institutua; Gobierno de Navarra / Nafarroako Gobernua
    Bap (biofilm-associated protein) is a 254-kDa staphylococcal surface protein implicated in formation of biofilms by staphylococci isolated from chronic mastitis infections. The presence of potential EF-hand motifs in the amino acid sequence of Bap prompted us to investigate the effect of calcium on the multicellular behavior of Bap-expressing staphylococci. We found that addition of millimolar amounts of calcium to the growth media inhibited intercellular adhesion of and biofilm formation by Bap-positive strain V329. Addition of manganese, but not addition of magnesium, also inhibited biofilm formation, whereas bacterial aggregation in liquid media was greatly enhanced by metal-chelating agents. In contrast, calcium or chelating agents had virtually no effect on the aggregation of Bap-deficient strain M556. The biofilm elicited by insertion of bap into the chromosome of a biofilm-negative strain exhibited a similar dependence on the calcium concentration, indicating that the observed calcium inhibition was an inherent property of the Bap-mediated biofilms. Site-directed mutagenesis of two of the putative EF-hand domains resulted in a mutant strain that was capable of forming a biofilm but whose biofilm was not inhibited by calcium. Our results indicate that Bap binds Ca2+ with low affinity and that Ca2+ binding renders the protein noncompetent for biofilm formation and for intercellular adhesion. The fact that calcium inhibition of Bap-mediated multicellular behavior takes place in vitro at concentrations similar to those found in milk serum supports the possibility that this inhibition is relevant to the pathogenesis and/or epidemiology of the bacteria in the mastitis process.