Photosynthesis is the central biological process that is the source of energy for all photosynthetic organisms and, via the food chain, for almost all other forms of life. In addition, the vast majority of energy used by mankind today is the legacy of ancient photosynthesis in the form of coal, oil, and natural gas. Knowledge of the mechanism of photosynthesis is crucial for obtaining an abundant food supply and cheap, dependable sources of energy. We study the molecular mechanism of the action of light triggered events in photosynthetic membranes, specifically, the protein dynamics adapted for light scheme in the context with specific cellular energetic status. We use mass spectrometry, molecular spectrophotometry, and molecular biology, to ask basic biophysical questions of proteins/protein complexes in response to specific environmental stimuli.