The ultrastructure of Chlorobaculum tepidum revealed by cryo-electron tomography.

Chlorobaculum (Cba) tepidum is a green sulfur bacterium that oxidizes sulfide, elemental sulfur, and thiosulfate for photosynthetic growth. As other anoxygenic green photosynthetic bacteria, Cba tepidum synthesizes bacteriochlorophylls for the assembly of a large light-harvesting antenna structure, the chlorosome. Chlorosomes are sac-like structures that are connected to the reaction centers in the cytoplasmic membrane through the BChl α-containing Fenna-Matthews-Olson protein.

Proteome profiling of the green sulfur bacterium Chlorobaculum tepidum by N-terminal proteomics.

In this study, we performed the first large-scale identification of N-terminal peptides from the green sulfur bacterium Chlorobaculum tepidum. Combined fractional diagonal chromatography (COFRADIC) was used to isolate protein N-terminal peptides from three different proteome preparations, and following LC-MS/MS analysis, over 621 different proteins were identified by their N-terminal peptides. Our data constitute the largest data set currently available for protein N-termini of prokaryotic photosynthetic organisms.

The chlorosome of Chlorobaculum tepidum: size, mass and protein composition revealed by electron microscopy, dynamic light scattering and mass spectrometry-driven proteomics.

Chlorosomes, the antenna complexes of green bacteria, are unique antenna systems in which pigments are organized in aggregates. Studies on isolated chlorosomes from Chlorobaculum tepidum based on SDS-PAGE, immunoblotting and molecular biology have revealed that they contain ten chlorosomal proteins, but no comprehensive information is available about the protein composition of the entire organelle. To extend these studies, chlorosomes were isolated from C.