Antenna mixing in photosynthetic membranes from Phaeospirillum molischianum.

ABSTRACT: We have investigated the adaptation of the light-harvesting system of the photosynthetic bacterium Phaeospirillum molischianum (DSM120) to very low light conditions. This strain is able to respond to changing light conditions by differentially modulating the expression of a family of puc operons that encode for peripheral light-harvesting complex (LH2) polypeptides. This modulation can result in a complete shift between the production of LH2 complexes absorbing maximally near 850 nm to those absorbing near 820 nm. In contradiction to prevailing wisdom, analysis of the LH2 rings found in the photosynthetic membranes during light adaptation are shown to have intermediate spectral and electrostatic properties. By chemical cross-linking and mass-spectrometry we show that individual LH2 rings a

SUBMITTER: Mascle-Allemand C 

PROVIDER: S-EPMC2851799 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature