Cell lifetime and chemical kinetics

AbstractAssuming Michaelis-Menten kinetics for the synthesis of an initiator of replication, the G1 phase time is calculated. Supposing that intra-cellular inhibitor and extra-cellular growth factor control the cell growth, the G1 phase time is calculated from concentrations of substrate, enzyme, intra-cellular inhibitor and extra-cellular growth factor. According to different concentrations, cells can have short or long G1 phase times which correspond either to cycling or resting cells. The production rate of proteins in G1 cells is also calculated. Different concentrations of substrate, enzyme, inhibitor and growth factor from one cell to the other in the same population lead to a statistical distribution of the G1 phase times. Thus, the G1 phase time variability is the result of biochemical statistical distributions