Download MendeleyStructural dynamics in the C terminal domain homolog of orange carotenoid Protein reveals residues critical for carotenoid uptake.
Harris, D., Muzzopappa, F., Glaser, F., Wilson, A., Kirilovsky, D., Adir, N.(2020) Biochim Biophys Acta Bioenerg 1861: 148214-148214
- PubMed: 32360310
- DOI: https://doi.org/10.1016/j.bbabio.2020.148214
- Primary Citation of Related Structures:
6S5L - PubMed 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.
Organizational Affiliation:
Schulich Faculty of Chemistry, Technion, Haifa 3200003, Israel; Grand Technion Energy Program (GTEP), Technion, Haifa 3200003, Israel.
