Ultrastructural Analysis and Identification of Envelope Proteins of “Candidatus Chloracidobacterium thermophilum” Chlorosomes

@article{Costas2011UltrastructuralAA,
  title={Ultrastructural Analysis and Identification of Envelope Proteins of “Candidatus Chloracidobacterium thermophilum” Chlorosomes},
  author={Amaya M. Garcia Costas and Y. Tsukatani and Steven P. Romberger and G. Oostergetel and E. Boekema and J. Golbeck and D. Bryant},
  journal={Journal of Bacteriology},
  year={2011},
  volume={193},
  pages={6701 - 6711}
}
ABSTRACT Chlorosomes are sac-like, light-harvesting organelles that characteristically contain very large numbers of bacteriochlorophyll (BChl) c, d, or e molecules. These antenna structures occur in chlorophototrophs belonging to some members of the Chlorobi and Chloroflexi phyla and are also found in a recently discovered member of the phylum Acidobacteria, “Candidatus Chloracidobacterium thermophilum.” “Ca. Chloracidobacterium thermophilum” is the first aerobic organism discovered to possess… Expand
Comparison of the physical characteristics of chlorosomes from three different phyla of green phototrophic bacteria.
TLDR
Spectral imaging revealed significant heterogeneity in the fluorescence emission of individual chlorosomes, likely reflecting the variations in BChl c homolog composition and internal arrangements of the stacked BChls within each chlorosome. Expand
Identification of the Bacteriochlorophylls, Carotenoids, Quinones, Lipids, and Hopanoids of “Candidatus Chloracidobacterium thermophilum”
TLDR
Two major xanthophyll carotenoids, echinenone and canthaxanthin, may confer enhanced protection against reactive oxygen species and could represent a specific adaptation to the highly oxic natural environment in which "Ca. Chloracidobacterium thermophilum" occurs. Expand
Glycolipid analyses of light-harvesting chlorosomes from envelope protein mutants of Chlorobaculum tepidum
TLDR
Glycolipid compositions of chlorosomes from the green sulfur bacterium Chlorobaculum tepidum mutants lacking one, two, or three Csm proteins are analyzed by HPLC equipped with an evaporative light-scattering detector to suggest that the CsmC, CsmD,CsmH, and other chlorosome proteins are involved in organizing MGDG and RGG and thereby affect the size and shape of the chlorosom. Expand
Reaction centers of the thermophilic microaerophile, Chloracidobacterium thermophilum (Acidobacteria) I: biochemical and biophysical characterization
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The reaction centers of C. thermophilum have some properties that resemble other homodimeric reaction centers but also have specific properties that are more similar to those of Photosystem I, contributing to the oxygen tolerance of this microaerophile. Expand
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TLDR
X-ray scattering and electron cryomicroscopy is combined with absorption spectroscopy and pigment analysis to compare the morphologies, structures, and pigment compositions of chlorosomes from Chloroflexus aurantiacus grown under two different light conditions and Chlorobaculum tepidum, providing information about the nature of interactions between bacteriochlorophylls and carotenoids in the protein-free environment of the chlorosome interior. Expand
Genomic and Phenotypic Characterization of Chloracidobacterium Isolates Provides Evidence for Multiple Species
TLDR
Comparative genomic studies and phenotypic properties indicate that the nine isolates represent three species within the genus Chloracidobacterium, the first and until now the sole genus in the phylum Acidobacteriota whose members perform chlorophyll-dependent phototrophy. Expand
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Abstract Green bacteria include chlorophototrophic members of the phyla Chlorobi, Chloroflexi, and Acidobacteria and are defined by their use of chlorosomes for light-harvesting. Despite their sharedExpand
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TLDR
This is the first description of aerotolerant type-I homodimeric RCs from the only known chlorophototrophic member of the phylum Acidobacteria and the isolated RC was photoactive in the presence of oxygen. Expand
[2Fe-2S] proteins in Chlorosomes: CsmI and CsmJ participate in light-dependent control of energy transfer in Chlorosomes of Chlorobaculum tepidum.
TLDR
Studying chlorosomes of Chlorobaculum tepidum in single, double, and triple-mutant strains suggested that cells contain both light-dependent and light-independent pathways for reducing the quenching species in chlorosome and that CsmI and CsmJ are components of a light- dependent pathway. Expand
A Panoply of Phototrophs: An Overview of the Thermophilic Chlorophototrophs of the Microbial Mats of Alkaline Siliceous Hot Springs in Yellowstone National Park, WY, USA
TLDR
The panoply of phototrophic organisms that occur in these mat communities are described and an introduction to their morphological appearance and other basic properties is provided. Expand
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