This title appears in the Scientific Report :
2003
Please use the identifier:
http://hdl.handle.net/2128/695 in citations.
Phot-LOV1 : photocycle of a blue-light receptor domain from the green alga Chlamydomonas reinhardtii
Phot-LOV1 : photocycle of a blue-light receptor domain from the green alga Chlamydomonas reinhardtii
The "Phot" protein family comprises blue-light photoreceptors that consist of two flavin mononucleotide (FMN)binding LOV (light, oxygen, and voltage) domains and a serine/threonine kinase domain. We have investigated the LOV1 domain of Phot1 from Chlamydomonas reinhardtii by time-resolved...
Saved in:
Personal Name(s): | Kottke, T. |
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Heberle, J. / Hehn, D. / Dick, B. / Hegemann, P. | |
Contributing Institute: |
Biologische Strukturforschung; IBI-2 |
Published in: | Biophysical journal, 84 (2003) S. 1192 - 1201 |
Imprint: |
New York, NY
Rockefeller Univ. Press
2003
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Physical Description: |
1192 - 1201 |
Document Type: |
Journal Article |
Research Program: |
Neurowissenschaften |
Series Title: |
Biophysical Journal
84 |
Subject (ZB): | |
Link: |
OpenAccess |
Publikationsportal JuSER |
The "Phot" protein family comprises blue-light photoreceptors that consist of two flavin mononucleotide (FMN)binding LOV (light, oxygen, and voltage) domains and a serine/threonine kinase domain. We have investigated the LOV1 domain of Phot1 from Chlamydomonas reinhardtii by time-resolved absorption spectroscopy. Photoexcitation of the dark form, LOV1-447, causes transient bleaching and formation of two spectrally similar red-shifted intermediates that are both assigned to triplet states of the FMN. The triplet states decay with time constants of 800 ns and 4 mus with an efficiency of >90% into a blue-shifted intermediate, LOV1-390, that is attributed to a thiol adduct of cysteine 57 to FMN C(4a). LOV1-390 reverts to the dark form in hundreds of seconds, the time constant being dependent on pH and salt concentration. In the mutant C57S, where the thiol adduct cannot be formed, the triplet state displays an oxygen-dependent decay directly to the dark form. We present here a spectroscopic characterization of an algal sensory photoreceptor in general and of a LOV1 domain photocycle in particular. The results are discussed with respect to the behavior of the homologous LOV2 domain from oat. |