Table II.

Inhibition of PEPC by malate [I_{50 (malate)}] in soluble protein extracts from leaves of the single-cell functioning C₄ species B. sinuspersici and S. aralocaspica and related chenopod species

Samples were taken after 5 h into the light and dark periods. PEPC from crude extracts was assayed at pH 7.2, 0.1 mm PEP. Values represent the mean of at least three independent determinations (ses are shown).

Species	Photosynthetic Type	I50 (malate)		I50 (malate)Light/Dark
					Light	Dark
		mm
B. sinuspersici	Single-cell C4	2.22 ± 0.03	2.00 ± 0.25	1.11
		0.60 ± 0.02a	0.23 ± 0.02a	2.61a
S. aralocaspica	Single-cell C4	0.69 ± 0.07	0.33 ± 0.06	2.09
H. persicum	Kranz C4	1.91 ± 0.04	0.47 ± 0.05	4.06
S. eltonica	Kranz C4	0.89 ± 0.05	0.26 ± 0.01	3.42
S. richteri	Kranz C4	2.17 ± 0.11	1.25 ± 0.14	1.74
S. linifolia	C3	3.93 ± 0.06	3.90 ± 0.11	1.01

^aWith B. sinuspersici, PEPC was also assayed at pH 7.2 with 0.055 mm PEP.