Natural　photosynthesis　serves　as　a　model　for　energy　and　chemical　conversions,　and　motivates　the　search　of　artificial　systems　that　mimic　nature′s　energy-　and　electron-transfer　chains.　However,　bioinspired　systems　often　suffer　from　the　partial　or　even　large　loss　of　the　charge　separation　state,　and　show　moderate　activity　owing　to　the　fundamentally　different　features　of　the　multiple　compounds.　Herein,　a　selenium　and　cyanamide-functionalized　heptazine-based　melon　(DA-HM)　is　designed　as　a　unique　bioinspired　donor–acceptor　(D-A)　light　harvester.　The　combination　of　the　photosystem　and　electron　shuttle　in　a　single　species,　with　both　n-　and　p-type　conductivities,　and　extended　spectral　absorption,　endows　DA-HM　with　a　high　efficiency　in　the　transfer　and　separation　of　photoexcited　charge　carriers,　resulting　in　photochemical　activity.　This　work　presents　a　unique　conjugated　polymeric　system　that　shows　great　potential　for　solar-to-chemical　conversion　by　artificial　photosynthesis.　©　2018　Wiley-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim