TY  - JOUR
AU  - Strauss, Jan
AU  - Deng, Longji
AU  - Gao, Shiqiang
AU  - Toseland, Andrew
AU  - Bachy, Charles
AU  - Zhang, Chong
AU  - Kirkham, Amy
AU  - Hopes, Amanda
AU  - Utting, Robert
AU  - Joest, Eike F.
AU  - Tagliabue, Alessandro
AU  - Loew, Christian
AU  - Worden, Alexandra Z.
AU  - Nagel, Georg
AU  - Mock, Thomas
TI  - Plastid-localized xanthorhodopsin increases diatom biomass and ecosystem productivity in iron-limited surface oceans
JO  - Nature microbiology
VL  - 8
IS  - 11
SN  - 2058-5276
CY  - London
PB  - Nature Publishing Group
M1  - PUBDB-2024-00420
SP  - 2050 - 2066
PY  - 2023
AB  - Microbial rhodopsins are photoreceptor proteins that convert light into biological signals or energy. Proteins of the xanthorhodopsin family are common in eukaryotic photosynthetic plankton including diatoms. However, their biological role in these organisms remains elusive. Here we report on a xanthorhodopsin variant (FcR1) isolated from the polar diatom Fragilariopsis cylindrus. Applying a combination of biophysical, biochemical and reverse genetics approaches, we demonstrate that FcR1 is a plastid-localized proton pump which binds the chromophore retinal and is activated by green light. Enhanced growth of a Thalassiora pseudonana gain-of-function mutant expressing FcR1 under iron limitation shows that the xanthorhodopsin proton pump supports growth when chlorophyll-based photosynthesis is iron-limited. The abundance of xanthorhodopsin transcripts in natural diatom communities of the surface oceans is anticorrelated with the availability of dissolved iron. Thus, we propose that these proton pumps convey a fitness advantage in regions where phytoplankton growth is limited by the availability of dissolved iron. 
LB  - PUB:(DE-HGF)16
C6  - pmid:37845316
UR  - <Go to ISI:>//WOS:001090801200001
DO  - DOI:10.1038/s41564-023-01498-5
UR  - https://bib-pubdb1.desy.de/record/601930
ER  -