6MQI

Crystal Structure of the All-trans Retinal bound R111K:Y134F:T54V:R132Q:P39Y:R59Y:L121Q mutant of Human Cellular Retinoic Acid Binding Protein II Irradiated with 400 nm Laser for 5 minutes at 1.87 Angstrom Resolution

Summary for 6MQI

• Entry DOI: 10.2210/pdb6mqi/pdb
• Descriptor: Cellular retinoic acid-binding protein 2, RETINAL (3 entities in total)
• Functional Keywords: ilbp, rhodopsin mimic, lipid binding protein
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 15878.20

Authors

Ghanbarpour, A.,Geiger, J. (deposition date: 2018-10-09, release date: 2019-01-09, Last modification date: 2023-10-11)

Primary citation

Ghanbarpour, A.,Nairat, M.,Nosrati, M.,Santos, E.M.,Vasileiou, C.,Dantus, M.,Borhan, B.,Geiger, J.H.
Mimicking Microbial Rhodopsin Isomerization in a Single Crystal.
J. Am. Chem. Soc., 141:1735-1741, 2019

PubMed Abstract: Bacteriorhodopsin represents the simplest, and possibly most abundant, phototropic system requiring only a retinal-bound transmembrane protein to convert photons of light to an energy-generating proton gradient. The creation and interrogation of a microbial rhodopsin mimic, based on an orthogonal protein system, would illuminate the design elements required to generate new photoactive proteins with novel function. We describe a microbial rhodopsin mimic, created using a small soluble protein as a template, that specifically photoisomerizes all- trans to 13- cis retinal followed by thermal relaxation to the all- trans isomer, mimicking the bacteriorhodopsin photocycle, in a single crystal. The key element for selective isomerization is a tuned steric interaction between the chromophore and protein, similar to that seen in the microbial rhodopsins. It is further demonstrated that a single mutation converts the system to a protein photoswitch without chromophore photoisomerization or conformational change.

PubMed: 30580520
DOI: 10.1021/jacs.8b12493

Experimental method

X-RAY DIFFRACTION (1.87 Å)