TY  - JOUR
AU  - Kriegsmann, J.
AU  - Brehs, M.
AU  - Klare, J.P.
AU  - Engelhard, M.
AU  - Fitter, J.
TI  - Sensory rhodopsin II/transducer complex formation in detergent and in lipid bilayers studied with FRET
JO  - Biochimica et biophysica acta / Biomembranes
VL  - 1788
SN  - 0005-2736
CY  - Amsterdam
PB  - Elsevier
M1  - PreJuSER-5168
SP  - 522 - 531
PY  - 2009
N1  - J. F. thanks G. Buldt (Forschungszentrum Julich) for continuous and sustainable support in his institute. This work was supported by the Deutsche Forschungsgerneinschaft (M.E.) and by a priority program SPP 1128 of Deutsche Forschungsgerneinschaft (FI 841/3-1,2 to J.F.). We are indebted to R. Schlesinger for providing us with bacteriorhodopsin and to R. Batra-Safferling for the discussions and comments on the manuscript.
AB  - The photophobic receptor from Natronomonas pharaonis (NpSRII) forms a photo-signalling complex with its cognate transducer (NpHtrII). In order to elucidate the complex formation in more detail, we have studied the intermolecular binding of both constituents (NpSRII and NpHtrII157; truncated at residue 157) in detergent buffers, and in lipid bilayers using FRET. The data for hetero-dimer formation of NpSRII/NpHtrII in detergent agrees well with KD values (approximately 200 nM) described in the literature. In lipid bilayers, the binding affinity between proteins in the NpSRII/NpHtrII complex is at least one order of magnitude stronger. In detergent the strength of binding is similar for both homo-dimers (NpSRII/NpSRII and NpHtrII/NpHtrII) but significantly weaker (KD approximately 16 microM) when compared to the hetero-dimer. The intermolecular binding is again considerably stronger in lipid bilayers; however, it is not as strong as that observed for the hetero-dimer. At a molar transducer/lipid ratio of 1:2000, which is still well above physiological concentrations, only 40% homo-dimers are formed. Apparently, in cell membranes the formation of the assumed functionally active oligomeric 2:2 complex depends on the full-length transducer including the helical cytoplasmic part, which is thought to tighten the transducer-dimer association.
KW  - Archaeal Proteins: chemistry
KW  - Archaeal Proteins: genetics
KW  - Archaeal Proteins: metabolism
KW  - Biophysical Phenomena
KW  - Detergents
KW  - Halobacteriaceae: chemistry
KW  - Halobacteriaceae: genetics
KW  - Halobacteriaceae: metabolism
KW  - Lipid Bilayers: chemistry
KW  - Models, Molecular
KW  - Protein Binding
KW  - Protein Multimerization
KW  - Protein Structure, Quaternary
KW  - Sensory Rhodopsins: chemistry
KW  - Sensory Rhodopsins: genetics
KW  - Sensory Rhodopsins: metabolism
KW  - Signal Transduction
KW  - Spectrophotometry
KW  - Archaeal Proteins (NLM Chemicals)
KW  - Detergents (NLM Chemicals)
KW  - HtrII protein, Natronobacterium pharaonis (NLM Chemicals)
KW  - Lipid Bilayers (NLM Chemicals)
KW  - Sensory Rhodopsins (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:19094962
UR  - <Go to ISI:>//WOS:000263794700025
DO  - DOI:10.1016/j.bbamem.2008.11.011
UR  - https://juser.fz-juelich.de/record/5168
ER  -