Evaluation of the food grade expression systems NICE and pSIP for the production of 2,5-diketo-D-gluconic acid reductase from Corynebacterium glutamicum

AMB Express

Table 3 Maximum 2,5-DKG reductase activities in cell free extracts of induced and noninduced L. lactis NZ3900 and Lb. plantarum TLG02 cultures

Not pH regulated cultivations of *L. lactis* and *Lb. plantarum*^a
Strain /plasmid	Volumetric activity (U L ^-1 fermentation broth)		Specific activity (U mg ^-1 protein)		Induction factor ^b
	Induced	Noninduced	Induced	Noninduced
L. lactis NZ3900/pVK51dkr	81.6 ± 9.3	16.0 ± 0.24	0.191 ± 0.022	0.038 ± 0.001	5.0
Lb. plantarum/pSIP603dkr	102 ± 5.8	21.7 ± 2.0	0.232 ± 0.022	0.054 ± 0.002	4.3
Lb. plantarum/pSIP609dkr	104 ± 2.75	23.8 ± 2.2	0.243 ± 0.017	0.055 ±0.001	4.4
pH regulated cultivations (pH 6.5) of *L. lactis* and *Lb. plantarum* ^a
Strain /plasmid	Volumetric activity (U L ^-1 fermentation broth)		Specific activity (U mg ^-1 protein)		Induction factor ^b
	Induced	Noninduced	Induced	Noninduced
L. lactis NZ3900/pVK51dkr	114 ± 1.9	14.6 ± 2.0	0.188 ± 0.001	0.022 ± 0.003	8.5
Lb. plantarum/pSIP603dkr	226 ± 5.9	27.2 ± 0.56	0.264 ± 0.026	0.032 ± 0.001	8.3
Lb. plantarum/pSIP609dkr	262 ± 1.7	30.2 ± 1.2	0.308 ± 0.016	0.033 ± 0.004	9.3

^a All data are mean values of three independent experiments. The maximum volumetric and specific activities measured in the culture are presented.
^b The induction factor was defined as the ratio between the specific activity obtained under induced conditions and the activity obtained under noninduced conditions.