Seed: a2ef4859d9047e39bc1ffc0ad189e859

Cells are straight or slightly curved rods, more than 3 μm wide, 8-16 μm long. Motile by a polar tuft of multitrichous flagella that can be seen in the light microscope, Gram negative, contain internal photosynthetic membranes of vesicular type in which the photosynthetic pigments bacteriochlorophyll a and carotenoids are located. Intracellular sulfur globules appear in most cases to be separated from the cytoplasm by a unit membrane which may be continuous with the cytoplasmic membrane