Figure 7.

The clpP-AUU Mutation Retards Loss of Cytochrome b₆f in Nitrogen Starvation.

(A) Chlorophyll fluorescence induction kinetics, in the presence (+) or absence (−) of DCMU, of TAP-grown cells (top) and cells starved for nitrogen for 61 hr (bottom). Solid lines, clpP-AUU; dotted lines, BI. (B) Evolution of the (F_max − F_s)/(F_max − F₀) parameter during nitrogen starvation. Solid line, clpP-AUU; dotted line, BI. (C) Immunoblot of total cell proteins as given for (A) and (B), reacted with an antibody to cytochrome f (Cyt f). (D) Protein chase experiment under nitrogen starvation conditions with antibodies to cytochrome f (Cyt f), subunit IV (Su IV), and the Rieske protein. Chloramphenicol was added at time 0.