Optimizing operational parameters for the enzymatic production of furandicarboxylic acid building block

Table 4 Catalytic performance parameters—FDCA concentration (mM) and yield (%), residual activity, and total turnover number (TTN)—for the production of FDCA from 6–12 mM HMF (including 6 mM re-dosage after 6 mM initial concentration) by the V367R and 8BxHMFO variants

Enzyme	HMF (mM)	Enzyme (µM)	FDCA (mM)	FDCA (%)	Residual activity (%)	TTN
V367R	6	2.50	6.0	100	67	7200
	8	2.50	7.0	88	0	8460
	10	2.50	5.0	50	0	6025
	12	2.50	2.0	17	0	2376
	6 + 6^a	2.50	9.3	78	2	11,200
	6 + 6^b	1.25	11.7	98	3	27,400
8BxHMFO	6	2.50	6.0	100	75	7200
	8	2.50	7.4	92	10	8830
	10	2.50	6.1	60	8	7204
	12	2.50	5.3	45	4	6500
	6 + 6^a	2.50	9.6	80	37	11,600
	6 + 6^b	1.25	10.7	89	36	26,200

Reactions were performed in 50 mM Tris/HCl, pH 8.0, for 6 days (12 days when the enzyme concentration was reduced to 1.25 µM) in the presence of catalase excess. The residual HMFO activity was estimated with vanillyl alcohol, and presented as percentage of the initial activity
^a,bSubstrate (6 mM) plus catalase re-dosage was done after 2 and 4 days of reaction, respectively

ISSN: 1475-2859