Unveiling long-range forces in light-harvesting proteins: Pivotal roles of temperature and light

Electrodynamic interactions between biomolecules are of potential biological interest for temporal and spatial molecular controls, warranting investigation of their activation through various mechanisms in living systems. Using a light-harvesting protein in the phycobilisome antenna system of red algae, we proved that not only light exposure but also thermal energy alone can trigger attractive electrodynamic interactions up to hundreds of nanometers, sustained by low-frequency collective modes. Activation of such modes and interactions might influence conformational rearrangements and energy transport within the phycobilisome system. This paradigm shift underscores the immense potential of biological systems in exploiting different forms of energy to achieve optimal energy transfer.