3P7N

Crystal structure of light activated transcription factor El222 from Erythrobacter litoralis

Summary for 3P7N

• Entry DOI: 10.2210/pdb3p7n/pdb
• Descriptor: Sensor histidine kinase, FLAVIN MONONUCLEOTIDE (3 entities in total)
• Functional Keywords: lov domain, light-activated transcription factor, dna binding protein
• Biological source: Erythrobacter litoralis
• Total number of polymer chains: 2
• Total formula weight: 58003.13

Authors

McNulty, R.,Luecke, H. (deposition date: 2010-10-12, release date: 2011-05-25, Last modification date: 2023-09-06)

Primary citation

Nash, A.I.,McNulty, R.,Shillito, M.E.,Swartz, T.E.,Bogomolni, R.A.,Luecke, H.,Gardner, K.H.
Structural basis of photosensitivity in a bacterial light-oxygen-voltage/helix-turn-helix (LOV-HTH) DNA-binding protein.
Proc.Natl.Acad.Sci.USA, 108:9449-9454, 2011

PubMed Abstract: Light-oxygen-voltage (LOV) domains are blue light-activated signaling modules integral to a wide range of photosensory proteins. Upon illumination, LOV domains form internal protein-flavin adducts that generate conformational changes which control effector function. Here we advance our understanding of LOV regulation with structural, biophysical, and biochemical studies of EL222, a light-regulated DNA-binding protein. The dark-state crystal structure reveals interactions between the EL222 LOV and helix-turn-helix domains that we show inhibit DNA binding. Solution biophysical data indicate that illumination breaks these interactions, freeing the LOV and helix-turn-helix domains of each other. This conformational change has a key functional effect, allowing EL222 to bind DNA in a light-dependent manner. Our data reveal a conserved signaling mechanism among diverse LOV-containing proteins, where light-induced conformational changes trigger activation via a conserved interaction surface.

PubMed: 21606338
DOI: 10.1073/pnas.1100262108

Experimental method

X-RAY DIFFRACTION (2.1 Å)