The bacteria were grown at 37°C or 42°C with rapid shaking (~200

The bacteria were grown at 37°C or 42°C with rapid shaking (~200 rpm) in flasks with a large headspace and harvested in early stationary phase (~5 × 109 colony forming units [CFU]/ml). Alternatively, the bacteria were grown under low oxygen tension in a bottle filled with medium to minimize the headspace and shaken slowly (75 rpm) to favor biofilm formation [29]. Bacteria were also grown in a strict anaerobic environment on CBA in a BD GasPak system (BD Diagnostic

Systems), or in CTT containing Oxyrase for Broth™ (Oxyrase, Mansfield, OH). For some experiments, the medium was supplemented with 2% NaCl, or the bacteria were harvested during mid- to late-stationary phase (48-72 h post-inoculation). For growth BTK signaling pathway inhibitors supplementation with Neu5Ac, 1 mg (50-μg/ml final concentration)

of Neu5Ac (Sigma Chemical Co.) was added to CBA, TTT, or to a chemically defined medium [31]. Polysaccharide purification H. somni was grown on CBA plates incubated in 5% CO2 or anaerobic conditions for 48-72 h at 37°C. The cells were scraped from the plates and suspended in phosphate buffered saline, pH 7.2, (PBS) to a turbidity of 150 Klett units (about 109 CFU/ml). After vigorous vortexing at room temperature, the cell suspension was incubated at 37°C for 1 h, vortexed again, and the cells removed by centrifugation (10,000 × g for 15 min). Cetavlon (hexadecyltrimethyl ammonium bromide) was added to a final concentration of 0.005 M. Any precipitate that formed was harvested and solubilized in distilled water. Rucaparib chemical structure Tideglusib No further purification was done on this sample. Alternatively, the bacteria were grown to late stationary phase in CTT (48-72 h

post-inoculation), the bacteria harvested as above, and Cetavlon added to the supernatant. Any precipitate that formed following addition of Cetavlon was further purified by enzyme digestion (RNase, DNase, and Proteinase K), phenol extraction, and ultracentrifugation to remove LOS, as described for purification of the capsular polysaccharide of Actinobacillus pleuropneumoniae [32]. The bacteria were also grown at 37°C in filled 1-L bottles containing TTT with shaking at 75 rpm for 4-5 days. The clear supernatant was carefully removed and the sediment was extracted with 45% aqueous phenol at room temperature, digested with DNase, RNase, and Proteinase K, and subjected to ultracentrifugation at 125,000 × g at 4°C, as described for purification of H. somni LOS [33], except that the supernatant from the ultracentrifugation step was retained. Polysaccharide in the supernatant was precipitated by the addition of 30 mM sodium acetate (final) and 5 volumes of cold (-20°C) 95% ethanol, and incubated at -20°C for at least 4 hours. The pellet obtained by centrifugation was suspended in distilled water, and eluted through a Sephacryl S-400 column (2.5 × 50 cm) with distilled water as eluent. The first fractions containing carbohydrate (determined by phenol-sulfuric acid assay) [34] were pooled and lyophilized.

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