, 1984). The antibiotics ampicillin and kanamycin were used, when required, at 20 and 10 μg mL−1, respectively. For the α-amylase tests, NYG-agar medium was supplemented with soluble starch at 0.2%; development of halos was carried out by exposing the medium, after bacterial growth, to vapors delivered by iodine crystals. Electrotransformation of Xac was performed as

described by do Amaral et al. (2005). Oligonucleotides are listed in the Supporting Information, Table S1. The integrative GFP expression vectors were constructed by the orderly ligation Selleckchem GSK1120212 of several DNA cassettes (Fig. 1). First, we produced a 57 bp double-stranded (ds)DNA by the annealing of two synthetic oligonucleotides: ribosome-binding site (RBS) (top and bottom). This dsDNA carried the RBS and had HindIII compatible ends. The dsDNA was ligated into Selleckchem FK228 pUC18/HindIII (NEB), generating

pTAS1. pTAS1 was digested with EcoRI/HindIII to receive the xylose promoter and its repressor DNA (xylR-pxyl), both extracted from the vector pEA18 (Gueiros-Filho & Losick, 2002), also digested with EcoRI/HindIII, giving rise to pTAS3. The resulting plasmid, pTAS3, was digested with BamHI/XbaI to receive a gfp gene (flanked by BamHI/XbaI), thus generating pPM1 (gfp was PCR amplified from pEA18 using the primers GFP_WO_STOP/GFP_F_C-ter). Because Xac is naturally resistant to ampicillin, a marker of pPM1, the expression cassette (xylR-pxyl-gfp) was moved to pCR2.1-TOPO (Invitrogen), which confers resistance to kanamycin. The strategy used was PCR ligation, exploiting the fact that both pUC18 and pCR2.1-TOPO have identical DNA segments flanking their polylinkers. The expression cassette was removed from pPM1 using the Pfu DNA polymerase (Fermentas) and the primers M13F and M13R; the

backbone of pCR2.1-TOPO was obtained using the primers M13F-TOPO and M13R-TOPO, both designed Farnesyltransferase to anneal outside of the polylinker, but pointing towards the kanamycin gene. The two amplification products were mixed in equimolar amounts, and ligated in a final PCR, without primers, giving rise to pPM2. Finally, a DNA fragment corresponding to bases 106–912 of the Xac amy gene (XAC0798) was PCR amplified using primers XamyFOR5/REV5 and ligated to pPM2/EcoRI, generating pPM2a (GenBank GQ139362). Extra restriction sites were added to pPM2a by reamplifying gfp with primers GFP_BHI_XhoI/GFP_NheI. The PCR product was digested with BamHI/XmaI, inserted between pPM2a BamHI/XmaI sites, giving rise to pPM7g (GU988753). Later, the gfp gene from pPM7g will be replaced by a mCherry cassette, for future protein colocalization experiments. All plasmids were checked by DNA sequencing. ORF XAC3408 was isolated by PCR using primers 3408F/3408R, digested with XbaI, and ligated to pPM2a/XbaI. Western blotting was as described by Sambrook et al. (1989). The anti-GFP primary antibody used was polyclonal raised in rabbits (F.J. Gueiros-Filho, Departamento de Bioquímica, IQ, USP, SP, Brazil).