2.3. Culture studies
The culture studies were carried out in a 1.5 L jar bioreactor (KO
biotech, Korea) containing 1.0 L of modified M9 medium or Oh’s
medium (Oh et al., 2012; see below). The inoculum was prepared
by two-step cultivation to ensure the preparation of reproducibly
active cells. The primary inoculum cultivation was conducted in
a 250 mL Erlenmeyer flask containing 50 mL LB medium at
200 rpm and 37 C for 8 h with an initial pH of 7.0. The secondary
inoculum was cultured under the same conditions as the primary
inoculum but only for 2–3 h.