tailieunhanh - Báo cáo khoa học: Experimental validation of metabolic pathway modeling An illustration with glycolytic segments from Entamoeba histolytica

In the search for new drug targets in the human parasite Entamoeba histolytica, metabolic control analysis was applied to determine, experimen-tally, flux control distribution of amebal glycolysis. The first (hexokinase, hexose-6-phosphate isomerase, pyrophosphate-dependent phosphofructo- | ễFEBS Journal Experimental validation of metabolic pathway modeling An illustration with glycolytic segments from Entamoeba histolytica Rafael Moreno-Sanchez Rusely Encalada Alvaro Marin-Hernandez and Emma Saavedra Departamento de Bioquimica Institute Nacionalde Cardiologia Mexico Keywords pathway reconstitution metabolic control analysis PPi inhibition PPi activation AMP modulation Correspondence E. Saavedra Departamento de Bioquimica Instituto Nacionalde Cardiologia Juan Badiano No. 1 Seccion XVI Tlalpan Mexico . 14080 Mexico Fax 52 55 5573 0994 Tel 52 55 5573 2911 ext. 1298 1422 E-mail emma_saavedra2002@ Database The mathematical models described here have been submitted to the Online Cellular Systems Modelling Database and can be accessed at http database moreno1 http jjj. database moreno2 of charge Received 27 November 2007 revised 1 April2008 accepted 6 May 2008 doi In the search for new drug targets in the human parasite Entamoeba histolytica metabolic control analysis was applied to determine experimentally flux control distribution of amebal glycolysis. The first hexokinase hexose-6-phosphate isomerase pyrophosphate-dependent phosphofructokinase PPi-PFK aldolase and triose-phosphate isomerase and final 3-phosphoglycerate mutase enolase and pyruvate phosphate dikinase glycolytic segments were reconstituted in vitro with recombinant enzymes under near-physiological conditions of pH temperature and enzyme proportion. Flux control was determined by titrating flux with each enzyme component. In parallel both glycolytic segments were also modeled by using the rate equations and kinetic parameters previously determined. Because the flux control distribution predicted by modeling and that determined by reconstitution were not similar kinetic interactions among all the reconstituted components were experimentally revised to unravel the causes of the .