Long-range organization of bacteriochlorophyll in chlorosomes of Chlorobium tepidum investigated by cryo-electron microscopy

FEBS Lett. 2007 Nov 27;581(28):5435-9. doi: 10.1016/j.febslet.2007.10.045. Epub 2007 Nov 5.

Abstract

Intact chlorosomes of Chlorobium tepidum were embedded in amorphous ice layers and examined by cryo-electron microscopy to study the long-range organization of bacteriochlorophyll (BChl) layers. End-on views reveal that chlorosomes are composed of several multi-layer tubules of variable diameter (20-30 nm) with some locally undulating non-tubular lamellae in between. The multi-layered tubular structures are more regular and larger in a C. tepidum mutant that only synthesizes [8-ethyl, 12-methyl]-BChl d. Our data show that wild-type C. tepidum chlorosomes do not have a highly regular, long-range BChl c layer organization and that they contain several multi-layered tubules rather than single-layer tubules or exclusively undulating lamellae as previously proposed.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bacteriochlorophylls / analysis*
  • Chlorobium / cytology*
  • Chlorobium / ultrastructure*
  • Cryoelectron Microscopy*
  • Intracellular Membranes / ultrastructure*

Substances

  • Bacteriochlorophylls