Incorporation of the bacterial reaction centre into dendrimersomes

Abstract

For the first time the ability of the first generation dendrimer belonging to the family of polyester-benzylether, (3,5)12G1-PE-BMPA-(OH)4, to form dendrimersomes is presented together with their capability to reconstitute the integral membrane protein complex called Reaction Centre (RC) purified from the photosynthetic bacterium Rhodobacter sphaeroides. Size, polydispersity and time stability of the empty and protein containing dendrimersomes are presented together with the photochemical activity of the guest protein. The RC presence appears to strongly enhance the self-assembly properties of the Janus dendrimer, leading to the formation of proteo-dendrimersomes showing a photochemical activity similar to that found for RC in solution. The interaction of the embedded RC with reduced cyt-c has also been investigated, indicating that the incorporation of the protein is vectorial (almost 90% of the guest protein faces the dendrimerosomes exterior with its cyt-c docking site) at variance with lecithin liposomes where the reconstitution is essentially statistical.