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Fig. 2. Glucose (Glc) phosphorylation to glucose-6-phosphate (Glc-6-P) by
mitochondrially bound hexokinase with exogenous ATP or with ATP generated by
oxidative phosphorylation. The rate of Glc phosphorylation was determined at
equivalent [ATP], either added exogenously in the absence of oxidative
phosphorylation (triangles) or generated by oxidative phosphorylation
(circles). From either source, the [ATP] was subsaturating, with the rate of
Glc phosphorylation well below that seen when the ATP levels were acutely
raised by addition of saturating levels of exogenous ATP (squares). Reprinted
with permission from BeltrandelRio and Wilson
(1991).