enzymatic rate law for irreversible non-modulated non-interacting unireactant enzymes Van Slyke-Cullen rate law Rate-law presented in "Donald D. Van Slyke and Glenn E. Cullen. The mode of action of urease and of enzymes in general. J. Biol. Chem., Oct 1914; 19: 141-180". It assumes that the enzymatic reaction occurs as two irreversible steps.E+S -> ES -> E+P. Although of the same form than the Henri-Michaelis-Menten equation, it is semantically different since K now represents the ratio between the production rate and the association rate of the enzyme and the substrate. <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:0000025">kcat</n2:ci></n2:bvar> <n2:bvar><n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000505">Et</n2:ci></n2:bvar> <n2:bvar><n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000515">S</n2:ci></n2:bvar> <n2:bvar><n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000372">Ks</n2:ci></n2:bvar> <n2:apply> <n2:divide /> <n2:apply> <n2:times /> <n2:ci>kcat</n2:ci> <n2:ci>Et</n2:ci> <n2:ci>S</n2:ci> </n2:apply> <n2:apply> <n2:plus /> <n2:ci>Ks</n2:ci> <n2:ci>S</n2:ci> </n2:apply> </n2:apply> </n2:lambda> </n2:semantics> </n0:math>