Revision as of 13:20, 29 September 2024

AJC7/S125D/ H342L

AJC7 two-point mutant

Construction

The mutation site of H342L is located far from S125D, allowing for the direct construction of the S125D/T181A double mutant using pET-28a(+)-AJC7-S125D as a template along with the primers designed for single-point mutation as outlined in [Design 1]. Following the mutation, the PCR products were verified using nucleic acid gel electrophoresis. The plasmids that exhibited the correct bands were subsequently transformed into E. coli BL21 (DE3) competent cells.

Fig. 1 point-mutation-localisation-and-primer-design

Fig. 2 nucleic-acid-gel-plot-of-colony-pcr

Indicator

The two-point mutant and wild-type strains were subjected to activation and amplification culture, followed by a series of protein purification procedures to extract the target proteins, as described in [Experimental]. The volume of the purified enzyme solution required for the 500 μL reaction system was determined based on the protein concentration indicated in [Experimental]. The final concentration of fructose in the system was set at 100 g/L, with the addition of 10 μL of Ni²⁺ as a catalyst. The reaction was conducted at 70°C for 5 hours, after which the products were analyzed using High-Performance Liquid Chromatography (HPLC). Sequence and Features