Low temperature phosphorescence, fluorescence and transient hole buming spectra of the photosystem 2 particles isolated from the cyanobacterium Synechococcus elongatus were measured. The role of photosynthetic activity was estimated by comparison of these spectroscopic methods. A model explaining chlorophyll fluorescence changes and both phosphorescence quantum efficiency increase and transient hole bimiing efficiency decrease connected with Chemical or heat photosynthetic deactivation is presented.