Kinetic modelling of phospholipid synthesis in Plasmodium knowlesi unravels crucial steps and relative importance of multiple pathways

Table 2 Parameter values and confidence intervals for the ODE (PL) model

Reaction ID	Reactions	Enzymes	Estimated Vm( μ M/min)	Estimated Km ( μ M)	Regime
R1	SerE → Ser	..	3.41∈ [ 3.08,3.95]	363∈ [ 326,410]
R2	Ser → PS	PSS	1.31∈ [ 0.517,1.65]	797∈ [ 352,1.25.10³]
R3	Ser → Etn	SD	2.62∈ [ 2.33,3.11]	24∈ [ 22.7,29.5]
R4	Etn → PEtn	EK	8.62∈ [ 6.19,13.3]	109∈ [ 75.6,193]
R5	PEtn → PCho	PMT	1.08∈ [ 0.725,13.9]	122∈ [ 78.5,2650]
R6	PS → PE	PSD	2.25∈ [ 0.747,2.94]	204∈ [ 152,413]
R7	PEtn → PE	ECT/CEPT	5.61∈ [ 4.19,7.65]	227∈ [ 175,353]
R8	PCho → PC	CCT/CEPT	0.413∈ [ 0.315,0.599]	31∈ [ 26.2,34.9]
R9	PE → PC	PEMT/PLMT	1.42.10³∈ [ 59.2,1.33.10⁴]	3.21.10⁵∈ [ 2.73.10⁴,1.92.10⁶]	L
R10	PC → PS	PSSbe	0.697∈ [ 0.318,0.944]	3.76∈ [ 0.06,3.88]
R11	PE → PS	PSSbe	89.9∈ [ 9.16,527]	1.71.10⁵∈ [ 1.58.10⁴,9.14.10⁵]	L
R12	PC →	..	1.57∈ [ 0.75,3.84]	24.1∈ [ 16.5,35.8]
R13	PS →	..	1.54∈ [ 0.013,3.28]	204∈ [ 41.1,1020]
R14	PE →	..	774∈ [ 9.44,1.08.10⁴]	1.55.10⁵∈ [ 2.52.10⁴,1.65.10⁶]	L
R15	ChoE → Cho	OCT/NPP	0.232∈ [ 0.182,0.323]	102∈ [ 91.9,109]
R16	Cho → PCho	CK	0.556∈ [ 0.384,0.882]	30.4∈ [ 22.8,36.7]
R17	EtnE → Etn	..	K_f=5.10⁻⁴m i n⁻¹∈ [ 10⁻⁴,2.5.10⁻³]	K_b=1.33.10⁻⁴m i n⁻¹∈ [ 4.45.10⁻¹⁵,1.4.10⁻³]

For the calculation of the confidence intervals see the Methods section and the Additional file 1 (the allowed objective function values were less than 1.5 times the global minimum). All the reactions have mass action kinetics, with the exception of the reaction 17 that has first order mass action law kinetics (the forward and the backward rate constants are denoted K_f and K_b, respectively). For those reactions whose regime is linear (L), only the ratio V_max/K_m is significant.

ISSN: 1752-0509