6XVU

Bacteriophytochrome response regulator from Deinococcus radiodurans

Summary for 6XVU

• Entry DOI: 10.2210/pdb6xvu/pdb
• Descriptor: Response regulator, CALCIUM ION (3 entities in total)
• Functional Keywords: response regulator, two-component system, signaling protein
• Biological source: Deinococcus radiodurans R1
• Total number of polymer chains: 4
• Total formula weight: 76639.58

Authors

Takala, H.,Ihalainen, J.A. (deposition date: 2020-01-22, release date: 2021-06-30, Last modification date: 2024-01-24)

Primary citation

Multamaki, E.,Nanekar, R.,Morozov, D.,Lievonen, T.,Golonka, D.,Wahlgren, W.Y.,Stucki-Buchli, B.,Rossi, J.,Hytonen, V.P.,Westenhoff, S.,Ihalainen, J.A.,Moglich, A.,Takala, H.
Comparative analysis of two paradigm bacteriophytochromes reveals opposite functionalities in two-component signaling.
Nat Commun, 12:4394-4394, 2021

PubMed Abstract: Bacterial phytochrome photoreceptors usually belong to two-component signaling systems which transmit environmental stimuli to a response regulator through a histidine kinase domain. Phytochromes switch between red light-absorbing and far-red light-absorbing states. Despite exhibiting extensive structural responses during this transition, the model bacteriophytochrome from Deinococcus radiodurans (DrBphP) lacks detectable kinase activity. Here, we resolve this long-standing conundrum by comparatively analyzing the interactions and output activities of DrBphP and a bacteriophytochrome from Agrobacterium fabrum (Agp1). Whereas Agp1 acts as a conventional histidine kinase, we identify DrBphP as a light-sensitive phosphatase. While Agp1 binds its cognate response regulator only transiently, DrBphP does so strongly, which is rationalized at the structural level. Our data pinpoint two key residues affecting the balance between kinase and phosphatase activities, which immediately bears on photoreception and two-component signaling. The opposing output activities in two highly similar bacteriophytochromes suggest the use of light-controllable histidine kinases and phosphatases for optogenetics.

PubMed: 34285211
DOI: 10.1038/s41467-021-24676-7

Experimental method

X-RAY DIFFRACTION (2.1 Å)