6BAK

The structure of the Stigmatella aurantiaca phytochrome chromophore binding domain T289H mutant

Summary for 6BAK

• Entry DOI: 10.2210/pdb6bak/pdb
• Related: 4RQ9
• Descriptor: Photoreceptor-histidine kinase BphP, 3-[5-[(Z)-(4-ethenyl-3-methyl-5-oxidanylidene-pyrrol-2-ylidene)methyl]-2-[[5-[(Z)-(3-ethenyl-4-methyl-5-oxidanylidene-pyrrol-2-ylidene)methyl]-3-(3-hydroxy-3-oxopropyl)-4-methyl-1H-pyrrol-2-yl]methyl]-4-methyl-1H-pyrrol-3-yl]propanoic acid (3 entities in total)
• Functional Keywords: signaling protein
• Biological source: Stigmatella aurantiaca DW4/3-1
• Total number of polymer chains: 1
• Total formula weight: 34405.29

Authors

Schmidt, M.,Stojkovic, E. (deposition date: 2017-10-13, release date: 2018-09-19, Last modification date: 2023-10-04)

Primary citation

Woitowich, N.C.,Halavaty, A.S.,Waltz, P.,Kupitz, C.,Valera, J.,Tracy, G.,Gallagher, K.D.,Claesson, E.,Nakane, T.,Pandey, S.,Nelson, G.,Tanaka, R.,Nango, E.,Mizohata, E.,Owada, S.,Tono, K.,Joti, Y.,Nugent, A.C.,Patel, H.,Mapara, A.,Hopkins, J.,Duong, P.,Bizhga, D.,Kovaleva, S.E.,St Peter, R.,Hernandez, C.N.,Ozarowski, W.B.,Roy-Chowdhuri, S.,Yang, J.H.,Edlund, P.,Takala, H.,Ihalainen, J.,Brayshaw, J.,Norwood, T.,Poudyal, I.,Fromme, P.,Spence, J.C.H.,Moffat, K.,Westenhoff, S.,Schmidt, M.,Stojkovic, E.A.
Structural basis for light control of cell development revealed by crystal structures of a myxobacterial phytochrome.
IUCrJ, 5:619-634, 2018

PubMed Abstract: Phytochromes are red-light photoreceptors that were first characterized in plants, with homologs in photosynthetic and non-photosynthetic bacteria known as bacteriophytochromes (BphPs). Upon absorption of light, BphPs interconvert between two states denoted Pr and Pfr with distinct absorption spectra in the red and far-red. They have recently been engineered as enzymatic photoswitches for fluorescent-marker applications in non-invasive tissue imaging of mammals. This article presents cryo- and room-temperature crystal structures of the unusual phytochrome from the non-photosynthetic myxo-bacterium (SaBphP1) and reveals its role in the fruiting-body formation of this photomorphogenic bacterium. SaBphP1 lacks a conserved histidine (His) in the chromophore-binding domain that stabilizes the Pr state in the classical BphPs. Instead it contains a threonine (Thr), a feature that is restricted to several myxobacterial phytochromes and is not evolutionarily understood. SaBphP1 structures of the chromophore binding domain (CBD) and the complete photosensory core module (PCM) in wild-type and Thr-to-His mutant forms reveal details of the molecular mechanism of the Pr/Pfr transition associated with the physiological response of this myxobacterium to red light. Specifically, key structural differences in the CBD and PCM between the wild-type and the Thr-to-His mutant involve essential chromophore contacts with proximal amino acids, and point to how the photosignal is transduced through the rest of the protein, impacting the essential enzymatic activity in the photomorphogenic response of this myxobacterium.

PubMed: 30224965
DOI: 10.1107/S2052252518010631

Experimental method

X-RAY DIFFRACTION (1.92 Å)