Study on the Reaction Conditions of the Enzymatic 5′-Phosphorylation of Inosine using Whole Cells of Engineered E. coli with Expression of Phosphotransferase

Abstract:

In this paper, the enzymatic phosphorylation of inosine in the 5′-position to produce inosine-5′-monophosphate (5′-IMP) with whole cells was studied, using the engineered E. coli BL21 with the expression of acid phosphotransferase (PHOC) phoc gene originated E.aerogenes IAM 1183. A maximum conversion rate of 63.36% was obtained after 6 h of enzymatic reaction at 30 oC in 100 mM inosine and 120 mM pyrophosphate (ppi) with PhOC activity of 45 U in a 150 mL reaction system. To further improve the conversion rate, the effects of three surfactants on the conversion rate were studied, and the conversion rate of inosine was increased to 74.59% at the addition of 0.3% Trion-x-100. This study provided basic data for the industrial application of the PHOC in production of 5′-IMP.