Effect of HL on WT and ΔFtsH4 cells diluted from stationary phase (SP).
(A) 1D SDS–PAGE/immunoblot analysis of membrane protein complexes isolated from WT and ΔFtsH4 cells in Exp or SP growth and treated with HL (500 μmol photons m−2 s−1/28°C) after dilution from SP to OD750nm 0.05 (HLsp). Antibodies specific to FtsH4, HliD, and PetC were used for immunodetection, with the PetC signal used to document equal loading of the samples based on the same OD750nm.
(B) Growth and photograph of WT and ΔFtsH4 cells after 48 h of HLsp. The OD750nm of both cultures was expressed as a percentage of the WT values. Values are means of four biological replicates ± SD. P = 0.006.
(C) Whole-cell absorption spectra of WT and ΔFtsH4 diluted from SP to OD750nm 0.05 and treated at 500 μmol photons m−2 s−1/18°C (HLsp/cold) for 0, 2, 6, 12, and 24 h. Cell cultures were photographed after cultivation for 24 h under HLsp/cold.