Table 3. Cellular acetyl-CoA and PHB synthase activity levels after heterotrophic culture in the dark.

Nutrient condition	Acetyl-CoA level (μg/g DW)		PHB synthase activity (nmol/min/mg protein)
	NORMAL	25.2 ± 5.1	20.3 ± 6.1	15.2 ± 4.2	13.2 ± 4.1
-N	30.7 ± 11.1	27.5 ± 9.7	35.1 ± 8.5*	31.3 ± 5.5*
-P	56.5 ± 10.7*	58.4 ± 11.7*	105.3 ± 15.3*	97.4 ± 10.1*
-N-P	52.1 ± 13.5*	56.6 ± 12.5*	98.5 ± 19.4*	111.5 ± 12.3*

Cells were cultured as described in Table 2. Data are average ± 1 SD from five independent experiments. Asterisks indicate significantly higher levels (P < 0.01, two-tailed t-test) than that obtained from NORMAL nutrient condition with the same acetate supply.