2.12 Western-blot analysis
For immunoblot (western-blot) analysis, thylakoids were isolated as described in Cerovic & Plesnicar (1984). Thylakoids proteins were extracted from membranes using 125 mM Tris-HCl, pH 6.8, 20% glycerol, 4% (w/v) SDS, 5% (v/v) β-mercaptoethanol, 0.1% (w/v) bromophenol blue. Protein concentration was estimated using a Bio-Rad protein assay kit (Bio-Rad Laboratories). Immunoblotting was performed as described in Mudd et al. (2008). Polyclonal antibodies raised against PTOX for both species (SA and SV ) were designed by the company according the sequence homology between species which was 63% (see blast sequences alignment results in supplemental data).