ABSTRACT
Photosynthetic organisms are directly exposed to changes in the environment and their survival dependsontheirabilitytoacclimatetosuchchanges.Thephotosyntheticmembranesarevery sensitivetostressfactorssuchastemperatureaboveandbelownormalphysiologicalrangeandUV radiation.ThemostdetrimentalcomponentofthenaturalsunlightisUV-A(320-400nm),which passesthroughthestratosphericozonelayeralmostunattenuatedanddamagesplantphotosynthesis [1-5]. The changes in photosynthetic membranes depend on growth conditions and plant species. TheprimarytargetofstressfactorsactioninplantsandalgaeisphotosystemII(PSII),sinceone ofthemostsensitivesiteistheoxygen-evolvingcomplex(OEC)[2,3,5].Thein…uenceofhightemperatureandUV-AradiationonPSII,aswellastheroleoftheorganizationofLHCII-PSII(lightharvestingantennaandcorecomplexofPSII)supercomplexonthedamagingeffectofthesestress factors are reviewed here.
