High level production of tyrosinase in recombinant Escherichia coli

Table 3 Influence of culture temperature on tyrosinase production

Temperature	μ_max(h^-1) ^a	OD_600max^b	Max. act. (U mL^-1) ^c
25 (°C)	0.31 ± 0.02	7.8 ± 0.9	0.12 ± 0.03
30 (°C)	0.52 ± 0.02	8.0 ± 0.7	0.22 ± 0.03
32 (°C)	0.60 ± 0.03	10.2 ± 0.9	0.76 ± 0.06
37 (°C)	0.66 ± 0.02	10.8 ± 1.0	0.36 ± 0.05

^a. μ_max: the maximal growth rate.
^b. OD_600max: the maximal optical density measured at 600 nm.
^c. Max. act.: the maximal volumetric activity of tyrosinase in units per mL of culture broth.
The freshly transformed JM109 (pMFvpt) cells were grown in shake flasks at 25, 30, 32 or 37°C and induced at the early-exponential growth phase (OD₆₀₀ ≈ 1.1) with 1.0 mM IPTG.