Chlorobium

Cross Index	Chlorobium
SuperSet	Prokaryote, Eubacteria Anoxygenic Phototrophic Bacteria
Compare	Purple Bacteria Internal sulfur granulesAmoebobacter, Chromatium, Lamprobacter modestohalophilus, Lamprocystis roseopersicina, Thiocapsa, Thiocystis, Thiodicyton, Thiopedia rosea , Thiospirillum jenense, External sulfur granules Ectothiorhodospira no granules Rhodobacter, Rhodocyclus, Rhodomicrobium vannieli, Rhodopila globiformis, Rhodopseudomonas, Rhodospirillum, Green Bacteria Sulfur granules Anachloris perfilievii, Chlorobium, Chloroherpeton thalassium, Pelodictyon, Prosthecachloris no sulfur granules Heliobacillus mobilis, Heliobacterium chlorum Multicellular filamentous Chloroflexus aurantiacus, Chloronema, Heliothrix oregonensis, Oscillochloris Anaerobic chemotropic Erythrobacter longus,
Contrast	Oxygenic Phototrophic Bacteria Archaea
Subset

Morphology

Chlorobium

CELLULAR

Staining	Gram-negative
Morphology	Cells spherical, ovoid, straight or curved rod-shaped, 0.3-1.1 um wide and 0.4-3 um long or, sometimes, much longer. Cells are often united in chains resembling streptococci or filaments; curved rod-shaped strains may form long spirals
Motility	Nonmotile
Specialized structures	The existing species exhibit one of two clearly distinguishable colours: culture or cell material is either green (grass-green) or brown (chocolate-brown). Significantly, these colours can also be recognized under the light microscope with brightfield illumination. Photo-synthetic pigments are located in thecytoplasmic membrane and the chlorosomes (Staehelin et al. 1978) which underlie and are attached to the cytoplasmic membrane. Storage materials are polyphosphate and polysaccharides (Sirevag and Ormerod 1977

Division

COLONIAL

Solid surface

Liquid

Growth Parameters

Chlorobium

PHYSIOLOGICAL

Tropism	phototrophic Photolithoautotrophic growth with sulfide or sulfur as electron donor
Oxygen	Obligately anaerobic
pH
Temperature	20-35`C
Requirements	Ammonia is used as nitrogen source; molecular nitrogen is fixed by many strains
Products	Bacteriochlorphylls c, d or e occur as major photosynthetic pigments, in addition to small amounts of bacteriochloro-phyll a. Chlorobactene is the major carotenoid component (Schmidt and Schiburr 1970). During sulfide oxidation, globules of elemental sulfur are formed outside the cells; the sulfur may be further oxidized to sulfate. In sulfide-reduced media, thiosulfate may be used as electron donor substrate. In the presence of reduced sulfur compounds and bicarbonate, a number of simple organic substrates can be photoassimilated
Enzymes
Unique features

ENVIRONMENTAL

Habitat	hydrogen sulfide-containing mud and water of freshwater, brackish water and marine environments.
Lifestyle
Pathogenicity

Distribution

Genome

Chlorobium

G+C Mol %

49.0-58.1 (Bd)

(Mandel et al. 1971)

Reference	Chlorobium
First citation	Nadson,G. A.1906. The morphology of inferior Algae II: Chlorobium limicola Nads., the green chlorophyll bearing microbe Bull Jard Bot St. Petersb 6:190
The Prokaryotes
Bergey's Systematatic	p 1684 N. Pfennig
Bergey's Determinative	p 361
References