TY  - JOUR
AU  - Mironova, O. S.
AU  - Budyak, I. L.
AU  - Büldt, G.
AU  - Schlesinger, R.
AU  - Heberle, J.
TI  - FT-IR difference spectroscopy elucidates crucial interactions of sensory rhodopsin I with the cognate transducer Htrl
JO  - Biochemistry
VL  - 46
SN  - 0006-2960
CY  - Columbus, Ohio
PB  - American Chemical Society
M1  - PreJuSER-59010
SP  - 9399 - 9405
PY  - 2007
N1  - Record converted from VDB: 12.11.2012
AB  - The phototaxis receptor sensory rhodopsin I (SRI) from Halobacterium salinarum interacts with its cognate transducer (HtrI) forming a transmembrane complex. After light excitation of the chromophore all-trans retinal, SRI undergoes structural changes that are ultimately transmitted to HtrI. The interaction of SRI with HtrI results in the closure of the receptor's proton pathway, which renders the photocycle recovery kinetics of SRI pH-independent. We demonstrate on heterologously expressed and reconstituted SRI-HtrI fusion proteins that the transmembrane part of HtrI (residues 1-52) as well as the downstream cytoplasmic part (residues 53-147) exhibit conformational changes after light excitation. The sum of these conformational changes is similar to those observed in the fusion constructs SRI-HtrI 1-71 and SRI-HtrI 1-147, which display pH-independent receptor kinetics. These results indicate the occurrence of spatially distinct conformational changes that are required for functional signal transmission. Kinetic and spectroscopic analysis of HtrI point mutants of Asn53 provides evidence that this residue is involved in the receptor-transducer interaction. We suggest that Asn53 plays a role similar to that of Asn74 of the HtrII from Natronobacterium pharaonis, the latter forming a hydrogen bond to the receptor within the membrane.
KW  - Archaeal Proteins: chemistry
KW  - Archaeal Proteins: genetics
KW  - Archaeal Proteins: radiation effects
KW  - Asparagine: chemistry
KW  - Asparagine: genetics
KW  - Halorhodopsins: chemistry
KW  - Halorhodopsins: genetics
KW  - Halorhodopsins: radiation effects
KW  - Light
KW  - Membrane Proteins: chemistry
KW  - Membrane Proteins: genetics
KW  - Membrane Proteins: radiation effects
KW  - Point Mutation
KW  - Protein Interaction Mapping
KW  - Recombinant Fusion Proteins: chemistry
KW  - Recombinant Fusion Proteins: genetics
KW  - Recombinant Fusion Proteins: radiation effects
KW  - Sensory Rhodopsins: chemistry
KW  - Sensory Rhodopsins: genetics
KW  - Sensory Rhodopsins: radiation effects
KW  - Spectroscopy, Fourier Transform Infrared
KW  - Archaeal Proteins (NLM Chemicals)
KW  - Halorhodopsins (NLM Chemicals)
KW  - Membrane Proteins (NLM Chemicals)
KW  - Recombinant Fusion Proteins (NLM Chemicals)
KW  - SRI protein, Halobacterium (NLM Chemicals)
KW  - Sensory Rhodopsins (NLM Chemicals)
KW  - htrI protein, Halobacterium salinarium (NLM Chemicals)
KW  - Asparagine (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:17655327
UR  - <Go to ISI:>//WOS:000248692400005
DO  - DOI:10.1021/bi700563f
UR  - https://juser.fz-juelich.de/record/59010
ER  -