They contain chlorosomes [3] and bacteriochlorophyll a and c.[4] Like other green sulfur bacteria C. tepidum requires light and specific compounds to perform anoxygenic photosynthesis.
[8] Within anaerobic sediment layers C. tepidum is able to couple carbon and sulfur cycling in a metabolically favorable way.
[3] The ellipsoidal shaped complexes act as light harvesting antenna to capture energy.
[3] Within each chlorosome are 215,000 ± 80,000 bacteriochlorophyll C[4] that act as pigment molecules and absorb unique wavelengths of light relative to their color.
[14][15] Several of its carotenoid metabolic pathways (including a novel lycopene cyclase) have similar counterparts in cyanobacteria.