Figure 3.

The effect of purified chloroplast lmw Hsp on whole-chain electron transport. Chloroplasts were isolated from 6-week-old unstressed tomato plants grown at 25/18°C day/night temperatures (i.e. plants without detectable levels of lmw Hsp). Chloroplasts were lysed and then incubated at 25 or 47°C; samples at 47°C were incubated with or without the addition of purified chloroplast lmw Hsp (0.0017 μg Hsp/μL). Assuming that all of the added protein was lmw Hsp and assuming a chlorophyll:PSII stoichiometry of 400, we estimate that there were approximately 14 lmw Hsps available per PSII. Results are means ± 1 se; n = 3. chl, Chlorophyll.