Affiliation:
1. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 1–40 Leninskie Gory, Moscow, Russia
Abstract
The absorption and circular dichroism spectra of chlorosomes isolated from green photosynthetic bacteria Chloroflexus aurantiacus grown under di erent illumination were studied. It was found that as the intensity of the growth light decreases, the spectra shift to the red side and become narrower and larger in amplitude. Theoretical modeling of the data obtained was performed using the theory of excitons. The conclusion was formulated that the number of bacteriochlorophyll c molecules in linear chains, which form the basis of the elementary blocks of chlorosomes, become greater as the intensity of light at which bacteria are grown decreases. It was suggested that this phenomenon increases the e ciency of capturing weak light uxes and thereby increases the chances of bacterial survival in conditions of sunlight de ciency.
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