Molecular Biology techniques Recombinant DNA techniques were carried out as previously described [38]. DNA ligase (New England Biolabs) was used as recommended by the manufacturers. E. coli DH5α cells were transformed using the calcium chloride protocol [39] and electroporation was used for transformation of E. coli SY327 cells [40]. Reporter plasmids were constructed in E. coli and conjugation into B. cenocepacia K56-2 was accomplished by triparental mating

[41] with E. coli DH5α carrying the helper plasmid pRK2013 [42]. DNA was amplified using a PTC-221 DNA engine (MJ Research) or an Eppendorf Mastercycler ep gradient S thermal cycler with Taq DNA polymerase, Phusion High-Fidelity PCR Kit or Proofstart DNA polymerase (Qiagen) (New England Biolabs). Amplification conditions were optimized for each primer pair and are available upon request. PCR products and plasmids were purified with QIAquick purification kit (Qiagen) selleck and QIAprep Miniprep kit (Qiagen), respectively. RNA isolation methods and RT-PCR analysis For RNA isolation, bacteria were grown in LB supplemented with 1 mM PA. Cells were harvested during early log phase (O.D. 600 = 0.3) and lysed in TE buffer pH 8.0 containing 400 μl/ml lysozyme for 5 minutes at room temperature. RNA was recovered with the RNeasy Mini kit (Qiagen), and samples eluted into (Diethyl Pyrocarbonate) DEPC treated water. Total

RNA was visualized in a 1% agarose gel in TAE buffer. Residual DNA was removed by on column treatment with DNase I (15 min, room Panobinostat price temperature), in DNase buffer (Qiagen). The RNA was then used as a template in reverse transcription (RT) or stored at -20°C until use. Reverse transcription was performed by SuperScript RT First-Strand synthesis using relevant gene specific primers (Additional file 1). The resultant ID-8 cDNA was PCR amplified using gene specific primers (Additional file 1), and the conditions optimized for each reaction. For every PCR, the appropriate controls with water and RNA in the absence of RT were included to ensure that the

amplicons obtained were a result of cDNA and not of contaminating genomic DNA. Construction of insertional mutant BCAL0210 of B. cenocepacia K56-2 BCAL0210 was disrupted using single crossover mutagenesis with plasmid pGPÙTp, a derivative of pGP704 that carries the dhfr gene flanked by terminator sequences [27]. Briefly, an internal 300-bp fragment of BCAL0210 was PCR amplified using appropriate primers (Additional file 1). The PCR-amplified was digested with XbaI and EcoRI respectively, cloned into the XbaI and EcoRI digested vector and maintained in E. coli SY327. The resulting plasmids (Table 1) were conjugated into B. cenocepacia strain K56-2 by triparental mating. Conjugants that had the plasmid integrated into the K56-2 genome were selected on LB agar plates supplemented with Tp 100 μg/ml and Gm 50 μg/ml.