Table I.

Effects of carbohydrate starvation on total ACAD activity in maize root tip high-density mitochondria

Substrate	ACAD Activity in the High-Density Mitochondria of 1000 Root Tips
	Nonstarved	Carbohydrate starved
50 μm	nmol min−1
Butyryl-CoA	7  ± 1	10  ± 2
Octanoyl-CoA	8  ± 2	16  ± 8
Palmitoyl-CoA	8  ± 2	20  ± 4

ACAD activity was measured as described in Methods. High-density mitochondria were purified from nonstarved or 48-h carbohydrate-starved maize root tips, as previously described (Couée et al., 1992). The size of the high-density mitochondrial pool in 1000 root tips was estimated from the yields of mitochondrial protein and mitochondrial enzyme markers (Couée et al., 1992). Results are the means ± se of at least three experiments.