期刊
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
卷 107, 期 12, 页码 5357-5362出版社
NATL ACAD SCIENCES
DOI: 10.1073/pnas.0914854107
关键词
chromatic adaptation; membrane protein; photosynthetic bacteria; Rhodospirillum molischianum
资金
- French Ministry of Research
- Centre National de la Recherche Scientifique (CNRS)
- Agence National de la Recherche [ANR-PNANO-06-0089]
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 and subunits can contain a mixture of polypeptides derived from the different operons. These observations show that polypeptide synthesis and insertion into the membrane are not strongly coupled to LH2 assembly. We show that the light-harvesting complexes resulting from this mixing could be important in maintaining photosynthetic efficiency during adaptation.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据