170
J.-F. Cornet et al.
Table 2. Stoichiometric equations for the synthesis of the constitutive fractions of S. platensis
Carbohydrates: P/2e- = 1.57
CO2 + 2.037H20 + 0.001H2SO4 + 3.330ATP + 2.127(NADPH, H +)
(Jc)
CH1.67oOo.711So.ool + 3.330Pi + 3.330ADP + 2.127NADP +
(21)
Proteins: P/2e- = 1.20
CO2 + 1.252HEO + 0.250HNO3 + 0.007H2SO4 + 3.702ATP + 3.081(NADPH, H +)
(JP----~) ~ CHI.526Oo.32-/No.25oSo.oo7 + 3.702Pi + 3.702ADP + 3.081NADP +
(22)
Lipids: P/2e- = 1.13
COz + 1.203H20 + 0.003H2SO4 + 3.013ATP + 2.659(NADPH, H +)
CH1.714Oo.2o4Po.oo38o.oo3 q- 3.010Pi + 3.013ADP + 2.659NADP +
(23)
Nucleic acids: P/2e- = 1.30
CO2 + 1.203HeO + 0.393HNO3 + 3.776ATP + 2.909(NADPH, H +)
(JNA)
CH1.27300.710No.393P0.104 + 3.672Pi + 3.776ADP + 2.909NADP +
(24)
Active biomass: P/2e- = 1.24
CO2 + 1.379H20 + 0.192HNO3 + 0.005HzSO4 + 3.568ATP + 2.874(NADPH, H §
--~"
CHl.56600.,~o5NoA92So.oosPo.o06 + 3.562Pi + 3.568ADP + 2.874NADP +
(25)
Exopolysaccharide: P/2e- = 1.73
COa + 2.220HZO + 0.015H2SO4 + 3.330ATP + 1.920(NADPH, H +)
CH1.65o0o.95o8o.o15 q- 3.330Pi + 3.330ADP + 1.920NADP §
(26)
Cofactor reduction:
2.779NADP + + 2.779H20 2.779(NADPH, H +) + 1.38902
(28)
ATP regeneration:
3.544(ADP + Pi) , 3.544ATP + 3.544H20
(29)
compounds in the biomass have been established by Cornet I-7] and are given in
Table 2.
The ATP demands have been calculated from the data of Oura [29] for the
carbohydrates and nucleic acid synthesis, from the data of Stouthamer [30] for
proteins and from information given by Tremoli~res [31] for lipids (Eqs. 21-24).
These equations of the four main components of biomass may be combined
to obtain an overall equation for active biomass under different limiting conditions of growth. According to the average compositions reported in Table 1, the
following stoichiometric equation represents the active biomass synthesis:
CO/+ 1.379H20 + 0.192HNO3 + 0.005H2SO 4 + 3.568ATP
+ 2.874(NADPH, H +) (JxA~ CH1.566Oo.4osNo.192So.oo5Po.oo 6
+ 3.562Pi + 3.568ADP + 2.874NADP §
(25)