Submitted by kdorfman on Tue, 10/23/2018 - 15:38

Info on growth of BL21(DE3):

Table 1 The maximum optical density and doubling time (DT) of E. coli BL21 (DE3) aerobic batch cultures in different minimal media supplemented with 0.4% glycerol

Medium DT (min) Max OD600nm
M9 102±9 1.2±0.19
N−C− 78±6 1.6±0.14
LR 66±3 3.1±0.14
M9 + Fe2+ 71±1 2.9±0.13
M9 + PO4 3− 71±2 2.2±0.08

N−C− minimal medium contained 10 mM of NH4Cl.

FeSO4·7H2O (0.01 mM) and KH2PO4 (107 mM) were added to M9 minimal medium to supplement it with iron and additional phosphate, respectively.

LeMaster and Richards minimal medium (LR medium) consisted of a mixture of buffer salts (KH2PO4 24.0 g l-1 and NaOH 1.0 g l-1), and mineral salts [(NH4)2SO4 1.675 g l-1, MgSO4·H2O 0.3 g l1, FeSO4·7H2O 3.0 mg l-1, concentrated H2SO4 10 μl l-1], prepared as 10× and 100× concentrates, respectively, and mixed as buffer salts–mineral salts–water in the ratio 10:1:89 (LeMaster and Richards 1982; Paliy et al. 2003).

Values are shown as arithmetic mean±standard error of the mean (n=3).

Only two replicates were used for N-C- and LR