Table I.

Total Rubisco activity following recovery assays

ExtractTimeTotal ActivityPercentage of 3 pm Control
μmol CO2 m−2s−1
Control9am 20.9  ± 0.2375
3pm 27.2  ± 0.25100
200 mmMalate3 pm 27.8  ± 0.28102
Control mix9 am + 3 pm 23.5  ± 0.2986

Rubisco total activities were measured for morning (9 am) and afternoon (3 pm) control extracts, or after spiking afternoon samples with 200 mm malate or in a mixture comprising 50% morning and 50% afternoon extract. The data are expressed as the means ± se of total Rubisco activity following an 8-min incubation (n = 5) and as mean percentages of the maximum total activity. Desalting morning and afternoon extracts had no discernible effect on either initial or total activities (data not shown).