Characterization of Recombinant D-Lyxose Isomerase

Abstract:

In this study，the D-lyxose isomerase gene derived from Peptococcaceae bacterium 1109 was cloned and introduced into E. coli BL21（DE3） for expression. The optimal substrate for the recombinant D-LI is D-lyxose，and it can efficiently catalyze the epimerization reaction between D-fructose and D-mannose. The specific activity of recombinantly expressed D-lysose isomerase can reach 2.544 U/mg when used D-fructose as substrate. It displayed maximal activity in presence of 1 mM Co2+ at pH 7.0 and 70 ℃. Under optimum conditions，95.85 g/L D-mannose was produced from 500 g/L D-fructose after reaction for 5 h，giving a conversion yield of 19.17%.