Cultivation of A. baumannii and E. coli

A. baumannii ATCC 19606^T was purchased from the American Type Culture Collection (ATCC) and porcine gastric mucin type III was obtained from Sigma-Aldrich. A. baumannii ATCC 19606^T was stored as Luria-Bertani (LB) broth/glycerol stocks at -80°C [31 ]. Escherichia coli MG1655 was obtained from F. Blattner, University of Wisconsin, USA. Cultures on LB agar were used to inoculate either LB broth [31 ] or swimming broth (SB, 1% tryptone, 0.5% NaCl), which were incubated overnight (12 to 14 h) at 37°C with shaking at 200 rpm. Swimming agar (SA) plates were made by adding 0.3% agarose to SB. Solutions containing mucin were sterilized by autoclaving as described previously [15 (link), 19 (link)–21 (link)]. A549 human alveolar epithelial cells, which were obtained from Dr. E. Lafontaine, College of Veterinary Medicine, University of Georgia, USA, were cultured in Dulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% heat-inactivated fetal bovine serum, ampicillin and streptomycin at 37°C in the presence of 5% CO₂, as previously described [32 (link)].