bacteriochlorophyll

plant anatomy

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June 18, 2026

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Bacteriochlorophyll is a pigment found in photosynthetic bacteria that is related to the chlorophyll found in higher plants. While chlorophyll in plants absorbs sunlight to convert solar energy into cellular energy through photosynthesis, bacteriochlorophyll absorbs light of longer, lower-energy wavelengths.12

Unlike plants, algae, and cyanobacteria, which use water as an electron source and release oxygen during photosynthesis, other photosynthetic bacteria utilize bacteriochlorophyll and require an electron donor other than water, thus not releasing oxygen. These bacteria, such as green and purple sulfur bacteria, use substances like sulfur or hydrogen gas as electron donors, and they require anaerobic conditions to perform photosynthesis.2

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bacteria
Phototrophic metabolism
…with a different pigment, called bacteriochlorophyll, which absorbs light of long, low-energy wavelengths. These organisms require an electron donor other than water and do not release oxygen. The green bacteria (Chlorobiaceae) and purple sulfur bacteria (Chromatiaceae) use elemental sulfur, sulfide, thiosulfate, or hydrogen gas as electron donor, whereas the purple…
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…with a different pigment, called bacteriochlorophyll, which absorbs light of long, low-energy wavelengths. These organisms require an electron donor other than water and do not release oxygen. The green bacteria (Chlorobiaceae) and purple sulfur bacteria (Chromatiaceae) use elemental sulfur, sulfide, thiosulfate, or hydrogen gas as electron donor, whereas the purple…
Read More