Structural dynamics in the C terminal domain homolog of orange carotenoid Protein reveals residues critical for carotenoid uptake

Dvir Harris, Fernando Muzzopappa, Fabian Glaser, Adjélé Wilson, Diana Kirilovsky, Noam Adir

Research output: Contribution to journalArticlepeer-review

Abstract

The structural features enabling carotenoid translocation between molecular entities in nature is poorly understood. Here, we present the three-dimensional X-ray structure of an expanded oligomeric state of the C-terminal domain homolog (CTDH) of the orange carotenoid protein, a key water-soluble protein in cyanobacterial photosynthetic photo-protection, at 2.9 Å resolution. This protein binds a canthaxanthin carotenoid ligand and undergoes structural reorganization at the dimeric level, which facilitates cargo uptake and delivery. The structure displays heterogeneity revealing the dynamic nature of its C-terminal tail (CTT). Molecular dynamics (MD) simulations based on the CTDH structures identified specific residues that govern the dimeric transition mechanism. Mutagenesis based on the crystal structure and these MD simulations then confirmed that these specific residues within the CTT are critical for carotenoid uptake, encapsulation and delivery processes. We present a mechanism that can be applied to other systems that require cargo uptake.

Original languageEnglish
Article number148214
JournalBiochimica et Biophysica Acta - Bioenergetics
Volume1861
Issue number8
DOIs
StatePublished - 1 Aug 2020

Keywords

  • Cyanobacteria
  • Ligand transfer
  • Molecular dynamics
  • Mutagenesis
  • Photoprotection
  • X-ray crystallography

All Science Journal Classification (ASJC) codes

  • Biophysics
  • Biochemistry
  • Cell Biology

Fingerprint

Dive into the research topics of 'Structural dynamics in the C terminal domain homolog of orange carotenoid Protein reveals residues critical for carotenoid uptake'. Together they form a unique fingerprint.

Cite this