Proteorhodopsin (PR or pRhodopsin) belongs to the family of bacterial transmembrane rhodopsins (retinylidene proteins). In 1971, the first microbial transmembrane rhodopsin - Bacteriorhodopsin was discovered in archea domain by Dieter Oesterhelt and Walther Stoeckenius. Later in 2000, the first bacterial transmembrane rhodopsins was discovered by Oded Béjà and Edward DeLong. The Proteorhodopsin is widely expressed in various type of aquatic habitats. It functions as light-driven proton pumps with the help of retinal chromophore at the active site. The light-driven proton pump gives bacteria en
Proteorhodopsin (PR or pRhodopsin) belongs to the family of bacterial transmembrane rhodopsins (retinylidene proteins). In 1971, the first microbial transmembrane rhodopsin - Bacteriorhodopsin was discovered in archea domain by Dieter Oesterhelt and Walther Stoeckenius. Later in 2000, the first bacterial transmembrane rhodopsins was discovered by Oded Béjà and Edward DeLong. The Proteorhodopsin is widely expressed in various type of aquatic habitats. It functions as light-driven proton pumps with the help of retinal chromophore at the active site. The light-driven proton pump gives bacteria energy in the form of adenosine triphosphate (ATP).
== Discovery == Efforts by Oded Béjà from Edward DeLong research group in pioneering bacterial artificial chromosome metagenomics analysis led the discovery of pRhodopsin in bacteria domain. It was first detected in uncultured gammaproteobacteria ribotype group SAR86 at Monterey Bay water column in 2000. Oded Béjà observed the sequence similarity between SAR86 pRhodopsin and bacteriorodopsin (a light driven proton pump in haloarchea) open reading frame. To further established pRhodopsin function as retinal-based light-driven proton pump, he expressed pRhodopsin open reading frame in Escherichia coli system. Before the discovery of bacterial Proteorhodpsin, it was understood that light driven active transport only evolved in extreme halophilic archaea domain (bacteriorodopsin, halorhodopsin, and sensory rhodopsin) and animal kingdom (as a visual rhodopsin). thumb|Proteorhodopsin containing Exiguobacterium sp. S17 at Laguna Socompa |310x310px == Species distribution == pRhodopsin is not confined to a single species and single habitat. It is distributed in many microorganisms from all over the world. pRhodopsin containing microorganisms is distributed in Gammaproteobacteria, Alphaproteobacteria, Betaproteobacteria, Flavobacteria, Planctomycetes, Cyanobacteria, Actinobacteria, marine Archaea, and different eukaryotic groups, including fungi and dinoflagellates. pRhodopsin containing microorganisms are habited in marine environments, sea ice, brackish environments, fresh water lakes and on high mountains. In the marine environment, pRhodopsin containing microorganisms is primarily found in photic zone.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).