TY - JOUR
T1 - Multifractality in intracellular enzymatic reactions
AU - Aranda, Juan S.
AU - Salgado, Edgar
AU - Muñoz-Diosdado, Alejandro
N1 - Funding Information:
The authors acknowledge the National Council for Science and Technology (CONACyT Mexico) and the National Polytechnic Institute (IPN Mexico) for financial support.
PY - 2006/5/21
Y1 - 2006/5/21
N2 - Enzymatic kinetics adjust well to the Michaelis-Menten paradigm in homogeneous media with dilute, perfectly mixed reactants. These conditions are quite different from the highly structured cell plasm, so applications of the classic kinetics theory to this environment are rather limited. Cytoplasmic structure produces molecular crowding and anomalous diffusion of substances, modifying the mass action kinetic laws. The reaction coefficients are no longer constant but time-variant, as stated in the fractal kinetics theory. Fractal kinetics assumes that enzymatic reactions on such heterogeneous media occur within a non-Euclidian space characterized by a certain fractal dimension, this fractal dimension gives the dependence on time of the kinetic coefficients. In this work, stochastic simulations of enzymatic reactions under molecular crowding have been completed, and kinetic coefficients for the reactions, including the Michaelis-Menten parameter KM, were calculated. The simulations results led us to confirm the time dependence of michaelian kinetic parameter for the enzymatic catalysis. Besides, other chaos related phenomena were pointed out from the obtained KM time series, such as the emergence of strange attractors and multifractality.
AB - Enzymatic kinetics adjust well to the Michaelis-Menten paradigm in homogeneous media with dilute, perfectly mixed reactants. These conditions are quite different from the highly structured cell plasm, so applications of the classic kinetics theory to this environment are rather limited. Cytoplasmic structure produces molecular crowding and anomalous diffusion of substances, modifying the mass action kinetic laws. The reaction coefficients are no longer constant but time-variant, as stated in the fractal kinetics theory. Fractal kinetics assumes that enzymatic reactions on such heterogeneous media occur within a non-Euclidian space characterized by a certain fractal dimension, this fractal dimension gives the dependence on time of the kinetic coefficients. In this work, stochastic simulations of enzymatic reactions under molecular crowding have been completed, and kinetic coefficients for the reactions, including the Michaelis-Menten parameter KM, were calculated. The simulations results led us to confirm the time dependence of michaelian kinetic parameter for the enzymatic catalysis. Besides, other chaos related phenomena were pointed out from the obtained KM time series, such as the emergence of strange attractors and multifractality.
KW - Enzymatic reactions
KW - Fractal kinetics
KW - Multifractality
KW - Stochastic simulation
UR - http://www.scopus.com/inward/record.url?scp=33646086005&partnerID=8YFLogxK
U2 - 10.1016/j.jtbi.2005.09.005
DO - 10.1016/j.jtbi.2005.09.005
M3 - Artículo
SN - 0022-5193
VL - 240
SP - 209
EP - 217
JO - Journal of Theoretical Biology
JF - Journal of Theoretical Biology
IS - 2
ER -