Table II.

Substrate preference of insect mitochondria^*

	Insect Mitochondria			Mammalian Muscle Mitochondria**
Substrate	House fly flight muscle	Locust flight muscle	ASE cell (this study)
Glycerophosphate	25	~1	1.4	0.1 – 1.0
Pyruvate + Malate	25	~ 1.4	0.8	1 – 3
Ketoglutarate	0.7	0.4	0.8	0.7–2
Octanoylcarnitine†	NA	1.1	0.7	1–2
Succinate	1	0.3	0.6	0.2 – 2

^*Substrate preference was calculated as the ratio of oxygen uptake with the indicated substrate and with glutamate. Values for house fly and locust were calculated from [24, 66].

^**Data for pigeon breast muscle, human skeletal muscle, and rat skeletal muscle were obtained from our lab (rat and human skeletal muscle) and compiled from [67–70] .

^†Data for locust were obtained with palmitoylcarnitine only. Mammalian data represent an average using palmitoylcarnitine and butyrylcarnitine. NA, not available.