modulated reversible Hill-type rate law modulated reversible Hill-type rate law with one modifier The modifier can be either an activator or inhibitor depending on the value of alpha (activator for values larger than 1, inhibitor for values smaller than 1; no effect if exactly 1). This reflects the effect of the presence of substrate and product on the binding of the modifier. The equation, derived by Hofmeyr and Cornish-Bowden (Comput. Appl. Biosci. 13, 377 - 385 (1997) <n0:math xmlns:n0="http://www.w3.org/1998/Math/MathML"> <n2:semantics xmlns:n2="http://biomodels.net/SBO/" definitionURL="http://biomodels.net/SBO/#SBO:0000062"> <n2:lambda> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000515"> substrate </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000512"> product </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000518"> Modifier </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000281"> Keq </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000324"> Vf </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000424"> Ks </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000423"> Kp </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000190"> h </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000287"> Mhalf </n2:ci> </n2:bvar> <n2:bvar> <n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000381"> alpha </n2:ci> </n2:bvar> <n2:apply> <n2:divide /> <n2:apply> <n2:times /> <n2:apply> <n2:divide /> <n2:apply> <n2:times /> <n2:ci> Vf </n2:ci> <n2:ci> substrate </n2:ci> </n2:apply> <n2:ci> Ks </n2:ci> </n2:apply> <n2:apply> <n2:minus /> <n2:cn> 1 </n2:cn> <n2:apply> <n2:divide /> <n2:ci> product </n2:ci> <n2:apply> <n2:times /> <n2:ci> substrate </n2:ci> <n2:ci> Keq </n2:ci> </n2:apply> </n2:apply> </n2:apply> <n2:apply> <n2:power /> <n2:apply> <n2:plus /> <n2:apply> <n2:divide /> <n2:ci> substrate </n2:ci> <n2:ci> Ks </n2:ci> </n2:apply> <n2:apply> <n2:divide /> <n2:ci> product </n2:ci> <n2:ci> Kp </n2:ci> </n2:apply> </n2:apply> <n2:apply> <n2:minus /> <n2:ci> h </n2:ci> <n2:cn> 1 </n2:cn> </n2:apply> </n2:apply> </n2:apply> <n2:apply> <n2:plus /> <n2:apply> <n2:divide /> <n2:apply> <n2:plus /> <n2:cn> 1 </n2:cn> <n2:apply> <n2:power /> <n2:apply> <n2:divide /> <n2:ci> Modifier </n2:ci> <n2:ci> Mhalf </n2:ci> </n2:apply> <n2:ci> h </n2:ci> </n2:apply> </n2:apply> <n2:apply> <n2:plus /> <n2:cn> 1 </n2:cn> <n2:apply> <n2:times /> <n2:ci> alpha </n2:ci> <n2:apply> <n2:power /> <n2:apply> <n2:divide /> <n2:ci> Modifier </n2:ci> <n2:ci> Mhalf </n2:ci> </n2:apply> <n2:ci> h </n2:ci> </n2:apply> </n2:apply> </n2:apply> </n2:apply> <n2:apply> <n2:power /> <n2:apply> <n2:plus /> <n2:apply> <n2:divide /> <n2:ci> substrate </n2:ci> <n2:ci> Ks </n2:ci> </n2:apply> <n2:apply> <n2:divide /> <n2:ci> product </n2:ci> <n2:ci> Kp </n2:ci> </n2:apply> </n2:apply> <n2:ci> h </n2:ci> </n2:apply> </n2:apply> </n2:apply> </n2:lambda> </n2:semantics> </n0:math>