<?xml version="1.0" encoding="UTF-8"?><!-- Created by JWS2SBML on 2010/10/08 16:38:37--><!-- A Systems Biology Approach to Investigate the Effect of pH-induced Gene Regulation on Solvent Production by Clostridium acetobutylicum in Continuous Culture	 Sylvia Haus, Sara Jabbari, Thomas Millat, Holger Janssen, Ralf-Jörg Fischer, Hubert Bahl, John King, Olaf Wolkenhauer	 BMC Systems Biology (2010)	 	 Corresponding author:	 Sara Jabbari	 sara.jabbari@nottingham.ac.uk --><sbml xmlns="http://www.sbml.org/sbml/level2/version4" level="2" version="4">	<model name="pH_shift_forward_3">  <listOfCompartments>    <compartment id="compartment" name="compartment" size="1"/>  </listOfCompartments>  <listOfSpecies>    <species id="extVariable" name="extVariable" compartment="compartment" initialConcentration="0" boundaryCondition="true" constant="true"/>    <species id="AC" name="AC" compartment="compartment" initialConcentration="0"/>    <species id="A" name="A" compartment="compartment" 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