This data was confirmed by reconstructing three independent B. abortus aidB mutants that were more sensitive than the wild-type strain to the presence of 0.4% EMS for 4 h. Indeed, we observed 10.2% ± 2.0 survival for the aidB mutants (n = 3), compared to 62% survival for the wild-type strain. This phenotype was complemented for the three strains, since we observed 61.3% ± 9.1 survival after 4 h in 0.4% EMS for the three aidB mutants complemented with the pDD001 plasmid (Table 1). In order to confirm that aidB mutant was more sensitive selleck chemicals to alkylating agents and not just EMS, we also tested the sensitivity of the aidB mutant and wild type strain to methyl methanesulfonate (MMS),

another alkylating agent. After 4 h of incubation with 0.02% MMS in rich medium, 45% of survival was obtained for the wild type strain, while only 2.1% of the aidB mutants survived, according Selleckchem Inhibitor Library to c.f.u. counting. Altogether, these experiments indicate that the B. abortus aidB

gene is probably involved in the repair or the prevention of alkylation damage, as suggested by its homology with E. coli AidB. It also indicates that AidB remains active when it is fused to YFP. Figure 1 The B. abortus aidB mutant is more sensitive to EMS. The sensitivity of B. abortus wild-type, aidB mutant strain, complemented aidB mutant and aidB overexpression strains was scored by counting the c.f.u. recovered after 4 h of incubation 2YT medium at 37°C, in the presence of 0.2, 0.4 or 1% EMS. The results are expressed as the percentage of c.f.u. compared to a control in which EMS was omitted. Bacteria were obtained from cultures stopped during Mannose-binding protein-associated serine protease exponential growth phase. Table 1 Strains and plasmids Strain Relevant Genotype or Description Reference or Source B. abortus     544 NalR Nalidixic acid-resistant B. abortus 544 J-M. Verger XDB1155 B. abortus 544 pdhS-cfp [16] XDB1120 XDB1155 + pDD001 This study XDB1121 Disrupted aidB in B. abortus 544 NalR This study XDB1122 XDB1155 + pDD003 This study XDB1123 XDB1155 + pDD007 This study XDB1124 XDB1155 + pDD008

This study XDB1127 XDB1121 + pDD001 This study XDB1118 B. abortus 544 with integrated pCVDH07 This study and [33] XDB1128 XDB1118 + pDD001 This study E. coli     DH10B Cloning strain Invitrogen S17-1 RP4-2, Tc::Mu,Km-Tn7, for plasmid mobilization [26] Plasmid Relevant Genotype or Description Reference or Source pDONR201 BP cloning vector Invitrogen pRH005 Gateway-compatible YFP low copy vector [34] pRH016 Gateway-compatible pBBR1-MCS1-3HA [34] pDD001 pRH005 carrying aidB This study pDD002 pDONR201 carrying aidB This study pDD003 pRH016 carrying aidB This study pDD007 pRH016 carrying acaD1 This study pDD008 pRH016 carrying acaD2 This study AidB-YFP is localized at the new pole, and at the constriction site in dividing cells The localization of the AidB-YFP fusion protein was analyzed in a B.