A desert Chlorella sp. that thrives at extreme high-light intensities using a unique photoinhibition protection mechanism

Guy Levin, Michael Yasmin, Varda Liveanu, Carmit Burstein, Rawad Hanna, Oded Kleifeld, Marc C. Simanowitz, Ayala Meir, Yaakov Tadmor, Joseph Hirschberg, Noam Adir, Gadi Schuster

Research output: Contribution to journalArticlepeer-review

3 Scopus citations

Abstract

While light is the driving force of photosynthesis, excessive light can be harmful. Photoinhibition is one of the key processes that limit photosynthetic productivity. A well-defined mechanism that protects from photoinhibition has been described. Chlorella ohadii is a green micro-alga, isolated from biological desert soil crusts, which thrives under extreme high light (HL). Here, we show that this alga evolved unique protection mechanisms distinct from those of the green alga Chlamydomonas reinhardtii or plants. When grown under extreme HL, a drastic reduction in the size of light harvesting antennae occurs, resulting in the presence of core photosystem II, devoid of outer and inner antennas. This is accompanied by a massive accumulation of protective carotenoids and proteins that scavenge harmful radicals. At the same time, several elements central to photoinhibition protection in C. reinhardtii, such as psbS, light harvesting complex stress-related, photosystem II protein phosphorylation and state transitions are entirely absent or were barely detected. In addition, a carotenoid biosynthesis-related protein accumulates in the thylakoid membranes of HL cells and may function in sensing HL and protecting the cell from photoinhibition. Taken together, a unique photoinhibition protection mechanism evolved in C. ohadii, enabling the species to thrive under extreme-light intensities where other photosynthetic organisms fail to survive.

Original languageEnglish
Pages (from-to)510-528
Number of pages19
JournalPlant Journal
Volume115
Issue number2
DOIs
StatePublished - Jul 2023

Keywords

  • Chlorella ohadii
  • carotenoid biosynthesis-related protein
  • photoinhibition
  • photoprotection
  • reactive oxygen species
  • thylakoid protein phosphorylation

ASJC Scopus subject areas

  • Genetics
  • Plant Science
  • Cell Biology

Fingerprint

Dive into the research topics of 'A desert Chlorella sp. that thrives at extreme high-light intensities using a unique photoinhibition protection mechanism'. Together they form a unique fingerprint.

Cite this