Display options
Share it on

Photosynth Res. 2002;71(1):83-90. doi: 10.1023/A:1014955614757.

Determination of the topography and biometry of chlorosomes by atomic force microscopy.

Photosynthesis research

Asunción Martinez-Planells, Juan B Arellano, Carles M Borrego, Carmen López-Iglesias, Frederic Gich, Jesús Garcia-Gil

Affiliations

  1. Section of Microbiology. Institute of Aquatic Ecology, University of Girona, Campus de Montilivi, E-17071, Girona, Spain, [email protected].

PMID: 16228503 DOI: 10.1023/A:1014955614757

Abstract

Isolated chlorosomes of several species of filamentous anoxygenic phototrophic bacteria (FAPB) and green sulfur bacteria (GSB) were examined by atomic force microscopy (AFM) to characterize their topography and biometry. Chlorosomes of Chloroflexus aurantiacus, Chloronema sp., and Chlorobium (Chl.) tepidum exhibited a smooth surface, whereas those of Chl. phaeobacteroides and Chl. vibrioforme showed a rough one. The potential artifactual nature of the two types of surfaces, which may have arisen because of sample manipulation or AFM processing, was ruled out when AFM images and transmission electron micrographs were compared. The difference in surface texture might be associated with the specific lipid and polypeptide composition of the chlorosomal envelope. The study of three-dimensional AFM images also provides information about the size and shape of individual chlorosomes. Chlorosomal volumes ranged from ca. 35 000 nm(3) to 247 000 nm(3) for Chl. vibrioforme and Chl. phaeobacteroides, respectively. The mean height was about 25 nm for all the species studied, except Chl. vibrioforme, which showed a height of only 14 nm, suggesting that GSB have 1-2 layers of bacteriochlorophyll (BChl) rods and GFB have approximately 4. Moreover, the average number of BChl molecules per chlorosome was estimated according to models of BChl rod organisation. These calculations yielded upper limits ranging from 34 000 BChl molecules in Chl. vibrioforme to 240 000 in Chl. phaeobacteroides, values that greatly surpass those conventionally accepted.

References

  1. Nature. 1994 Feb 17;367(6464):614-21 - PubMed
  2. J Bacteriol. 1982 May;150(2):905-15 - PubMed
  3. Biophys J. 2000 Oct;79(4):2105-20 - PubMed
  4. J Struct Biol. 1997 Jul;119(2):99-108 - PubMed
  5. Phys Rev Lett. 1986 Mar 3;56(9):930-933 - PubMed
  6. J Electron Microsc (Tokyo). 2000;49(3):395-406 - PubMed
  7. Appl Environ Microbiol. 1995 Feb;61(2):784-7 - PubMed
  8. Science. 1996 Jun 21;272(5269):1788-91 - PubMed
  9. Nat Struct Biol. 2000 Sep;7(9):715-8 - PubMed
  10. Biochim Biophys Acta. 1980 Jan 4;589(1):30-45 - PubMed
  11. J Mol Biol. 1998;283(1):83-94 - PubMed
  12. Arch Microbiol. 2001 Mar;175(3):226-33 - PubMed
  13. Biochim Biophys Acta. 1986 Jan 28;848(1):69-76 - PubMed
  14. Nat Struct Biol. 2000 Aug;7(8):644-7 - PubMed
  15. J Electron Microsc (Tokyo). 2000;49(3):459-62 - PubMed
  16. Nature. 2000 May 25;405(6785):418-9 - PubMed
  17. Proc Natl Acad Sci U S A. 1999 Oct 12;96(21):12180-5 - PubMed
  18. J Mol Biol. 1996 Dec 20;264(5):907-18 - PubMed
  19. J Mol Biol. 2000 Jun 23;299(5):1271-8 - PubMed
  20. Biophys J. 1999 Aug;77(2):1150-8 - PubMed
  21. Photochem Photobiol. 2000 Jun;71(6):715-23 - PubMed
  22. Photosynth Res. 1996 Oct;50(1):41-59 - PubMed

Publication Types