Model for the light-harvesting complex I (B875) of Rhodobacter sphaeroides
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Updated: Oct 29, 2026

In Vitro Reconstitution of Light-harvesting Complexes of Plants and Green Algae
Published on: October 10, 2014
1Beckman Institute and Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 USA.
Abstract:
The light-harvesting complex I (LH-I) of Rhodobacter sphaeroides has been modeled computationally as a hexadecamer of alphabeta-heterodimers, based on a close homology of the heterodimer to that of light-harvesting complex II (LH-II) of Rhodospirillum molischianum. The resulting LH-I structure yields an electron density projection map that is in agreement with an 8.5-A resolution electron microscopic projection map for the highly homologous LH-I of Rs. rubrum. A complex of the modeled LH-I with the photosynthetic reaction center of the same species has been obtained by a constrained conformational search. This complex and the available structures of LH-II from Rs. molischianum and Rhodopseudomonas acidophila furnish a complete model of the pigment organization in the photosynthetic membrane of purple bacteria.
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