218
L. E. COE, MARY H. COE, and IN-YOUNG LEE
Assume energy metabolism may be divided into 4 internally regulated
blocks:
VpFK
V LDH
G
~--+
F ~-->- L
v R
2RH2 + 02
~--+
2Hp + 2R
c
.g
-"l
a:;
u
~ '"
-0
E
::::!.
ATP+ X
10
I
aD::
--'
3
52
00
10
I
aD::
--'
3
52
Vs
~--+
ADP + Pi + Y
20
15
5
20
o 0 L....!. _ _ --'-_ _ """'---_ _ '--_---'--_......I 0
o
2
4
6
II moles/ml celis
Fig. 1. Velocities of respiration (VR), the head end of glycolysis (VPFK), the
tail end of glycolysis (VLDH) and ATP hydrolysis (Vs) as functions of ADP and
esterified phosphate (Pest).
Units for VR, in !Lmoles O2 and VLDH, in glucose equivalents, are given at left;
units for VPFK, in glucose equivalents, and Vs, in ILmoles ATP, are given at right.
The points cover the first 60 sec after glucose addition, the highest point in each
series being at 10 sec. Conditions: 37 cC, 54 mM phosphate buffer, 2.9 % V / V cells,
0.77 mM glucose (cf. ref. [3] for further details). Symbols: +--, Vs;
6 .... , VR; 0--, VLDH; X--, VPFK; A, VR prior to glucose addition.
Pest estimated by summation of changes in fructose diphosphate, triose phosphate, and other phosphate esters