Index >> Bacterial Photosynthesis >> Chlorobiaceae

Chlorobiaceae - The green sulphur bacteria were the earliest photosynthetic bacteria. They utilized hydrogens from H₂S to photoreduce NAD+ directly to NADH + H+. releasing sulphate as a byproduct.

The bacteria apparently did not have the Calvin Benson cycle for reducing CO₂ they utilized the reductive tricarboxylic cycle, which resembles the mitochondrial Krebs cycle run in reverse. In Chlorobium, cytochrome c as an electron carrier is strictly photosynthetic.