TY  - JOUR
AU  - Poetsch, A.
AU  - Berzborn, R. J.
AU  - Heberle, J.
AU  - Link, T. A.
AU  - Dencher, N. A.
AU  - Seelert, H.
TI  - Biophysics and Bioinformatics Reveal Structural Differences of the Two Peripheral Stalk Subunits in Chloroplast ATP Synthase
JO  - Journal of biochemistry
VL  - 141
SN  - 0021-924x
CY  - Tokyo
PB  - Soc.
M1  - PreJuSER-59160
SP  - 411 - 420
PY  - 2007
N1  - Record converted from VDB: 12.11.2012
AB  - ATP synthases convert an electrochemical proton gradient into rotational movement to produce the ubiquitous energy currency adenosine triphosphate. Tension generated by the rotational torque is compensated by the stator. For this task, a peripheral stalk flexibly fixes the hydrophilic catalytic part F1 to the membrane integral proton conducting part F(O) of the ATP synthase. While in eubacteria a homodimer of b subunits forms the peripheral stalk, plant chloroplasts and cyanobacteria possess a heterodimer of subunits I and II. To better understand the functional and structural consequences of this unique feature of photosynthetic ATP synthases, a procedure was developed to purify subunit I from spinach chloroplasts. The secondary structure of subunit I, which is not homologous to bacterial b subunits, was compared to heterologously expressed subunit II using CD and FTIR spectroscopy. The content of alpha-helix was determined by CD spectroscopy to 67% for subunit I and 41% for subunit II. In addition, bioinformatics was applied to predict the secondary structure of the two subunits and the location of the putative coiled-coil dimerization regions. Three helical domains were predicted for subunit I and only two uninterrupted domains for the shorter subunit II. The predicted length of coiled-coil regions varied between different species and between subunits I and II.
KW  - Amino Acid Sequence
KW  - Biophysical Phenomena
KW  - Biophysics
KW  - Chloroplast Proton-Translocating ATPases: chemistry
KW  - Computational Biology
KW  - Molecular Sequence Data
KW  - Protein Structure, Secondary
KW  - Protein Subunits: chemistry
KW  - Sequence Alignment
KW  - Spectroscopy, Fourier Transform Infrared
KW  - Spinacia oleracea: enzymology
KW  - Protein Subunits (NLM Chemicals)
KW  - Chloroplast Proton-Translocating ATPases (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:17283010
UR  - <Go to ISI:>//WOS:000245676800013
DO  - DOI:10.1093/jb/mvm045
UR  - https://juser.fz-juelich.de/record/59160
ER  -