In families known to group together enzymes of differing substrat

In families known to group together enzymes of differing substrate specificity, the “”related to”" annotation could be upgraded to “”candidate”" by using a broad activity descriptor, for instance β-glycosidase instead of β-mannosidase. Biofilm production To test biofilm production overnight cultures were used to inoculate liquid MSgg medium (100 mmol l-1 MOPS pH 7.0, 0.5% AZD1152 mouse glycerol, 0.5% glutamate, 5 mm potassium

phosphate pH 7.0, 50 μg ml-1 tryptophan, 50 mg ml-1 phenylalanine, 2 mmol l-1 MgCl2, 0.7 mmol l-1 CaCl2, 50 μmol l-1 FeCl3, 50 μmol l-1 MnCl2, 2 μmol l-1 thiamine, 1 μmol l-1 ZnCl2) [5] and cells grown at 37°C in static conditions for up to 48 h. Cells forming a solid layer at the liquid-air interface were considered as biofilm producers. To quantify biofilm formation, bacteria were grown in MSgg medium at 37°C for 3 days in 6-wells selleck compound polystyrene microtiter plates. Culture

medium was removed and wells washed with phosphate-buffered saline (PBS). The solid biofilm layer was stained for 30 min with two ml 0.1% (wt/vol) crystal violet in an isopropanol-methanol-PBS solution (1:1:18 [vol/vol]). Wells were then washed again with dH2O and air-dried (about 30 min). The crystal violet bound to the wells was extracted with 2 ml ethanol-acetone (80:20) and the optical density (OD) of each well was measured at 570 nm. Mucin adhesion and degradation assays Mucin adhesion assays were performed as previously described [Borja et al. 2010]. 100 μl of a mucin (from porcine stomach type III; Sigma-Aldrich) solution in PBS (10 mg/ml) was 3-MA concentration immobilized on the wells of 96-well polystyrene microtiter plates for one hour at 37°C, followed by overnight incubation at 4°C. Wells were washed twice with 200 μl of PBS and incubated with 20 g/l bovine serum albumin (BSA) (Sigma-Aldrich), for 2 h at 4°C. Non-bound BSA was eliminated by extensive Amino acid washes with PBS, and 100 μl of bacterial cell suspensions (approximately 109 CFU/ml), was added to the wells and incubated at 37°C for 1 h. Wells were washed five times with 200 μl of sterile citrate buffer to remove unbound

bacteria. Two hundred μl of 0.5% (v/v) Triton X-100 was added to eliminate attached bacteria. The content of each well was thoroughly mixed with a micropipette, and 100 μl of the resulting suspensions plated to obtain the CFU/well. Results are the average of three independent experiments. Mucin degradation assays were performed as previously reported [Fakhry et al., 2009]. Cells were grown overnight and spotted on Medium B plates: tryptone (Oxoid) 7.5 g/l; casitone (Difco) 7.5 g/l; yeast extract (Oxoid) 3.0 g/l; meat extract (Merck) 5.0 g/l; NaCl (BDH) 5.0 g/l; K2HPO-3H2O (BDH) 3.0 g/l; KH2PO (BDH) 0.5 g/l; MgSO-7H2O (BDH) 0.5 g/l; cysteine HCl (Sigma) 0.5 g/l; resazurin (BDH) 0.002. g/l; D-(1)-glucose (BDH) 10 or 30 g/l, purified hog gastric mucin (HGM) 3 g/l and agarose (Sigma) 1.5 g/100 ml.

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