To prepare A. citrulli inoculum,
bacterial cells were pelleted from 1.5 ml of overnight LB
broth culture by centrifugation at 13,000 rpm for 1 min. Cells were
washed with and resuspended in 0.1 M phosphate-buffered saline
(PBS; 137 mM NaCl, 5.6 mM Na2HPO4, 2.7 mM KCl, and 1.5
mM KH2PO4).