anoxygenic photosynthesis

Edge evidence

• sulfide feeds electrons into photosynthetic electron transport METPO:2007402

  Sulfide and other non-water donors feed electrons into the single photosystem.

  • DOI:10.3389/fmicb.2024.1417714 Review of green sulfur bacteria supports sulfide as electron donor and the absence of oxygen production.
• photosynthetic electron transport enables anoxygenic photosynthesis RO:0002327

  Bacteriochlorophyll-based electron flow realizes anoxygenic photosynthesis.

  • DOI:10.1016/j.tim.2006.09.001 Bryant & Frigaard describe anoxygenic photosynthesis across five prokaryotic phyla using bacteriochlorophyll and a single photosystem.
• bacteriochlorophyll absorbs light energy

  Bacteriochlorophyll harvests light energy to drive single-photosystem photochemistry.

  • DOI:10.1016/j.tim.2006.09.001 Bryant & Frigaard: anoxygenic photosynthesis uses bacteriochlorophyll and a single photosystem to capture light energy.
• light energy powers photosynthetic electron transport

  Absorbed light energy drives photosynthetic electron transport through the single photosystem.

  • DOI:10.1016/j.tim.2006.09.001 Light energy captured by bacteriochlorophyll powers single-photosystem electron flow in anoxygenic phototrophs.
• Type I reaction center enables anoxygenic photosynthesis RO:0002327

  A homodimeric Type I reaction-center photosystem mediates anoxygenic photosynthesis across diverse phyla.

  • DOI:10.3390/biom14030311 Niederman: diverse homodimeric Type I reaction-center photosystems underpin anoxygenic phototrophic bacteria; complemented by Tsuji et al. DOI:10.1038/s41586-024-07180-y showing Chloroflexota use a Type I RC.
• Type I reaction center part of photosynthetic electron transport biolink:part_of

  The Type I reaction center is the photochemical core of the single-photosystem electron transport chain.

  • DOI:10.1038/s41586-024-07180-y Tsuji et al.: an anoxygenic phototroph of the Chloroflexota uses a Type I reaction centre for photosynthetic electron transport.
• sulfide oxidized to elemental sulfur (S0) METPO:2007405

  Sulfide donated to the photosystem is oxidized to elemental sulfur (S0) during anoxygenic photosynthesis.

  • DOI:10.3389/fmicb.2024.1417714 Kushkevych et al.: H2S serves as electron donor and is oxidized to S0 in green/purple sulfur bacteria anoxygenic photosynthesis.