Production of Bdellovibrio bacteriovorus cell suspensions using different host bacterium culture media to produce either bdellocysts or vegetative cells

摘要

Production of Bdellovibrio bacteriovorus cell suspensions comprising culturing the cells in a suspension of Gram-negative bacterial cells in media with different phosphate (P2O5), manganese (Mn2+) and zinc (Zn2+) concentrations to produce either resting Bdellovibrio cells (bdellocysts) or vegetative Bdellovibrio cells, is new. Novel method of producing Bdellovibrio bacteriovorus cell suspensions comprising: (a) culturing Gram-negative bacteria in a complex medium up to the end of the logarithmic growth phase; (b) purifying the cells by centrifugation; (c) suspending the cells in a sodium-free medium containing 4-8 mM calcium, 1-3 mM magnesium, 10-70 mM potassium and either: (A) 4-25 mM P2O5, 0.007-0.06 mM Mn2+ and less than 2 mM Zn2+ for producing bdellocysts; or (B) less than 4 mM P2O5, 0.02-4 mM Mn2+ and 2-4 mM Zn2+ for producing vegetative Bdellovibrio cells; and (d) culturing B. bacteriovorus in the bacterial cell suspension in a fermenter or shaker bottles at 5-30 deg C under microaerophilic and/or aerobic conditions provided by stirring, preferably at 200 rpm, and an aeration at a rate of 0.1-1 l/hour per liter of working volume. An Independent claim is also included for a bdellocyst suspension containing bdellocysts in an amount of 2 * 105 pfu/ml.