2.2. Arsenic resistance assays

Cultures of B. vulgatus ATCC 8482 were grown at 37 °C with shaking in degassed Schneider's insect medium containing 20% heat-inactivated fetal bovine serum containing the indicated concentrations of As(V), As(III), MAs(V) or MAs(III) in an anaerobic jar with GasPak™ After approximately 24 h, when the cultures had attained an A_600nm = 1.0, the cells were collected at 4 °C by centrifugation in tightly capped tubes filled with nitrogen gas.