Long-range organization of bacteriochlorophyll in chlorosomes of Chlorobium tepidum investigated by cryo-electron microscopy.
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.
Oostergetel
Gert T
GT
Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Reus
Michael
M
Gomez Maqueo Chew
Aline
A
Bryant
Donald A
DA
Boekema
Egbert J
EJ
Holzwarth
Alfred R
AR
D001429:Bacteriochlorophylls / Q000032:analysis*; D041883:Chlorobium / Q000166:cytology* / Q000648:ultrastructure*; D020285:Cryoelectron Microscopy; D007425:Intracellular Membranes / Q000648:ultrastructure*
D001429:Bacteriochlorophylls