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Updated: Jul 19, 2026

Autofluorescence Imaging to Evaluate Red Algae Physiology
Published on: February 17, 2023
Prokaryotic photosynthesis and phototrophy illuminated
Donald A Bryant1, Niels-Ulrik Frigaard
1Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA. dab14@psu.edu
Abstract:
Genome sequencing projects are revealing new information about the distribution and evolution of photosynthesis and phototrophy. Although coverage of the five phyla containing photosynthetic prokaryotes (Chlorobi, Chloroflexi, Cyanobacteria, Proteobacteria and Firmicutes) is limited and uneven, genome sequences are (or soon will be) available for >100 strains from these phyla. Present knowledge of photosynthesis is almost exclusively based on data derived from cultivated species but metagenomic studies can reveal new organisms with novel combinations of photosynthetic and phototrophic components that have not yet been described. Metagenomics has already shown how the relatively simple phototrophy based upon rhodopsins has spread laterally throughout Archaea, Bacteria and eukaryotes. In this review, we present examples that reflect recent advances in phototroph biology as a result of insights from genome and metagenome sequencing.
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