TY - JOUR AU - Guo, H. AU - Kottke, T. AU - Hegemann, P. AU - Dick, B. TI - The Phot LOLV2 Domain and its Interaction with LOV1 JO - Biophysical journal VL - 89 SN - 0006-3495 CY - New York, NY PB - Rockefeller Univ. Press M1 - PreJuSER-49345 SP - 402 - 412 PY - 2005 N1 - Record converted from VDB: 12.11.2012 AB - Phot proteins are homologs of the blue-light receptor phototropin. We report a comparative study of the photocycles of the isolated, light-sensitive domains LOV1 and LOV2 from Chlamydomonas reinhardtii phot protein, as well as the construct LOV1/2 containing both domains. Transient absorption measurements revealed a short lifetime of the LOV2-wt triplet state (500 ns), but a long lifetime (287 micros) of the triplet in the mutant LOV2-C250S, in which the reactive cysteine is replaced by serine. For LOV1, in comparison, corresponding numbers of 800 ns and 4 micros for the two conformers in LOV1-wt, and 27 micros for LOV1-C57S have been reported. The triplet decay kinetics in the mixed domains LOV1/2-wt, LOV1/2-C57S, and LOV1/2-C250S can be analyzed as the superposition of the behavior of the corresponding single domains. The situation is different for the slow, thermal reaction of the photoadduct back to the dark form. Whereas the individual domains LOV1 and LOV2 show two decay components, the double domains LOV1/2-C57S and LOV1/2-C250S both show only a single component. The interaction of the two domains does therefore not manifest itself during the lifetime of the triplet states, but changes the decay behavior of the adduct states. KW - Animals KW - Anions KW - Cations KW - Chlamydomonas reinhardtii: metabolism KW - Cryptochromes KW - Cysteine: chemistry KW - DNA Adducts KW - Flavoproteins: chemistry KW - Hot Temperature KW - Hydrogen-Ion Concentration KW - Ions KW - Kinetics KW - Light KW - Models, Chemical KW - Mutation KW - Photons KW - Photoreceptor Cells, Invertebrate: chemistry KW - Protein Binding KW - Protein Structure, Tertiary KW - Serine: chemistry KW - Sodium Chloride: pharmacology KW - Spectrophotometry KW - Temperature KW - Time Factors KW - Anions (NLM Chemicals) KW - Cations (NLM Chemicals) KW - Cryptochromes (NLM Chemicals) KW - DNA Adducts (NLM Chemicals) KW - Flavoproteins (NLM Chemicals) KW - Ions (NLM Chemicals) KW - Cysteine (NLM Chemicals) KW - Serine (NLM Chemicals) KW - Sodium Chloride (NLM Chemicals) KW - J (WoSType) LB - PUB:(DE-HGF)16 C6 - pmid:15879473 C2 - pmc:PMC1366540 UR - <Go to ISI:>//WOS:000230114500043 DO - DOI:10.1529/biophysj.104.058230 UR - https://juser.fz-juelich.de/record/49345 ER -