Table III.

Growth and photosynthetic properties of the control and mutant strains

	WTK	MatD1	DoubleExt
Doubling time in dim light (h)	12.2 ± 0.9	12.7 ± 0.8	12.3 ± 1.0
Variable fluorescencea	0.42 ± 0.07	0.47 ± 0.12	0.45 ± 0.15
Rates of electron transfer (% of WTK)
Whole chainb	100	100 ± 5	98 ± 12
PSIIc	100	96 ± 10	95 ± 10

Each value is the mean ± sd of at least three independent measurements.

^a Determined as the maximum flash-induced fluorescence yield normalized to the initial level of fluorescence, (F_M − F₀)/F₀, in the presence of 40 μm DCMU. 

^b Determined by polarographic measurements of rates of oxygen evolution in the presence of 10 mm NaHCO₃ in BG11. The WT^K samples evolved 207 ± 15.5 μmol O₂ mg⁻¹ Chl h⁻¹. 

^c Determined by polarographic measurements of rates of oxygen evolution in the presence of 0.5 mm 2,6-dichloro-p-benzoquinone and 1 mm K₃Fe(CN)₆ in BG11. The WT^K samples evolved 543 ± 92.6 μmol O₂ mg⁻¹ Chl h⁻¹.