TABLE 2.

Effect of [¹²Ci] on N¹⁴ CO⁻ transport by Synechococcus sp. strain UTEX 625 grown in standing culture^a

Experimental condition (with 1 mM KO14CN)	% of control value at 20 s			% of control value at 2 min
	N14CO− uptake	Pool	14C fixation	N14CO− uptake	Pool	14C fixation
0 mM KHCO3	100	100b	100c	100	100d	100e
2 mM KHCO3	48.2 ± 9.3	45.4 ± 16.2	47.5 ± 21.6	38.4 ± 15.2	41.0 ± 12.9	24.9 ± 10.6
5 mM KHCO3	49.4 ± 7.3	46.4 ± 19.3	42.9 ± 12.2	39.6 ± 14.6	41.5 ± 18.7	30.4 ± 19.7

^aValues were determined using method C in BTP-HCl buffer, pH 8, containing 25 mM NaCl. Light was supplied at 300 μmol of photons m⁻² s⁻¹. Data are the average of seven experiments ± standard deviations.

^bControl value, 6.0 ± 2.0 mM.

^cControl value, 0.06 μmol of C mg⁻¹ Chl.

^dControl value, 11.0 ± 7.0 mM.

^eControl value, 0.23 μmol of C mg⁻¹ Chl.