title: Leptosphaeria rhodopsin: bacteriorhodopsin-like proton pump from a eukaryote.
abstract: Bacteriorhodopsin-like proteins provide archaea and eubacteria with a unique bioenergetic pathway comprising light-driven transmembrane proton translocation by a single retinal-binding protein. Recently, homologous proteins were found to perform photosensory functions in lower eukaryotes, but no active ion transport by eukaryotic rhodopsins was detected. By demonstrating light-driven proton pumping in a fungal rhodopsin from Leptosphaeria maculans, we present a case of a retinal-based proton transporter from a eukaryote. This result implies that in addition to oxidative phosphorylation and chlorophyll photosynthesis, some lower eukaryotes may have retained the archaeal route of building an electrochemical transmembrane gradient of protons.
authors.affiliation: Department of Physics, University of Guelph, Guelph, ON, Canada N1G 2W1.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Waschuk
authors.forename: Arandi G
authors.initials: AG
authors.lastname: Bezerra
authors.forename: Lichi
authors.initials: L
authors.lastname: Shi
authors.forename: Leonid S
authors.initials: LS
authors.lastname: Brown
mesh_terms: D001203:Ascomycota / Q000378:metabolism*; D001436:Bacteriorhodopsins / Q000737:chemistry*; D002734:Chlorophyll / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007477:Ions; D007700:Kinetics; D007834:Lasers; D008027:Light; D008081:Liposomes / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism; D010766:Phosphorylation; D010843:Pichia / Q000378:metabolism; D011485:Protein Binding; D017494:Proton Pumps; D011522:Protons; D012243:Rhodopsin / Q000737:chemistry*; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013997:Time Factors
chemical_list: D007477:Ions; D008081:Liposomes; D017494:Proton Pumps; D011522:Protons; D002734:Chlorophyll; D001436:Bacteriorhodopsins; D012243:Rhodopsin; D010100:Oxygen