9EUT

Cryo-EM structure of the full-length Pseudomonas aeruginosa bacteriophytochrome in its Pr state

Summary for 9EUT

• Entry DOI: 10.2210/pdb9eut/pdb
• EMDB information: 19981
• Descriptor: Bacteriophytochrome, 3-[2-[(Z)-[3-(2-carboxyethyl)-5-[(Z)-(4-ethenyl-3-methyl-5-oxidanylidene-pyrrol-2-ylidene)methyl]-4-methyl-pyrrol-1-ium -2-ylidene]methyl]-5-[(Z)-[(3E)-3-ethylidene-4-methyl-5-oxidanylidene-pyrrolidin-2-ylidene]methyl]-4-methyl-1H-pyrrol-3- yl]propanoic acid (2 entities in total)
• Functional Keywords: photosensor, photoreceptor, phytochrome, bacterial protein, cytosolic protein
• Biological source: Pseudomonas aeruginosa
• Total number of polymer chains: 2
• Total formula weight: 165361.07

Authors

Bodizs, S.,Westenhoff, S. (deposition date: 2024-03-28, release date: 2024-09-04, Last modification date: 2024-11-20)

Primary citation

Bodizs, S.,Meszaros, P.,Grunewald, L.,Takala, H.,Westenhoff, S.
Cryo-EM structures of a bathy phytochrome histidine kinase reveal a unique light-dependent activation mechanism.
Structure, 32:1952-1962.e3, 2024

PubMed Abstract: Phytochromes are photoreceptor proteins in plants, fungi, and bacteria. They can adopt two photochromic states with differential biochemical responses. The structural changes transducing the signal from the chromophore to the biochemical output modules are poorly understood due to challenges in capturing structures of the dynamic, full-length protein. Here, we present cryoelectron microscopy (cryo-EM) structures of the phytochrome from Pseudomonas aeruginosa (PaBphP) in its resting (Pfr) and photoactivated (Pr) state. The kinase-active Pr state has an asymmetric, dimeric structure, whereas the kinase-inactive Pfr state opens up. This behavior is different from other known phytochromes and we explain it with the unusually short connection between the photosensory and output modules. Multiple sequence alignment of this region suggests evolutionary optimization for different modes of signal transduction in sensor proteins. The results establish a new mechanism for light-sensing by phytochrome histidine kinases and provide input for the design of optogenetic phytochrome variants.

PubMed: 39216473
DOI: 10.1016/j.str.2024.08.008

Experimental method

ELECTRON MICROSCOPY (2.95 Å)