Abstract
Green photosynthetic bacteria have antenna complexes named chlorosomes which absorb light and transport the energy to the photochemical reaction center, where redox energy can be accumulated. The structure of chlorosomes from Chlorobium limicola, i.e. higher-order aggregates of bacteriochlorophyll c (BChl c) isomeric mixture, has been proposed. The structure of the in vitro BChl c aggregates was almost revealed using 13C-labeled BChl c and non-labeled BChl c. Reconstitution of chlorosomes is essential to determine the structure of chlorosomes by the same method. Reconstitution can be examined by electronic absorption, circular dichroism spectroscopy, and sucrose density-gradient centrifugation.
Chlorosome-like aggregates can be formed, in a buffer containing lipids, by injecting a chloroform/methanol extract of chlorosomes (BChl c isomeric mixtures). In addition to this method, several means of preparation of chlorosome-like higher-order BChl c structures have been examined.
