Effect of recombinant human intestinal alkaline phosphatase on LPS
RecIAP was diluted to 50 U/mL with Tris-HCl (50 mmol L-1, pH 6.0-8.0) buffer. 990 μl recIAP and 100μl LPS solution (Escherichia coli 0111: B4, Sigma, LPS final concentration 1μg ml-1) were mixed together thoroughly and then incubated at 37°C for 3 hours. The absorbance at 545nm was measured by the TAL method (test tube Limulus amebocyte lysate kit, ec32545s, Xiamen limulus lysate Biotechnology Co., Ltd.), and the LPS content was determined using a standard curve. At physiological pH (7.4), recIAP (enzyme activity was 1, 5, 10 U ml-1) was incubated with LPS (5ng ml-1) at 37°C for 3 hours, and the LPS content was measured again. For the above measurements, recIAP that was inactivated at 65°C for 60 minutes was used as a blank control.