scholarly journals Structural Asymmetry of F1-ATPase Caused by the γ Subunit Generates a High Affinity Nucleotide Binding Site

1996 ◽  
Vol 271 (5) ◽  
pp. 2433-2438 ◽  
Author(s):  
Chitose Kaibara ◽  
Tadashi Matsui ◽  
Toru Hisabori ◽  
Masasuke Yoshida
Keyword(s):  
Binding Site ◽  
Nucleotide Binding ◽  
Nucleotide Binding Site ◽  
Structural Asymmetry ◽  
F1 Atpase ◽  
High Affinity ◽  
Γ Subunit

Measurement of site occupancy and rotation speed of F1-ATPase without noncatalytic nucleotide binding site

2003 ◽  
Vol 43 (supplement) ◽  
pp. S134
Author(s):  
R. Kon-Shimo ◽  
E. Muneyuki ◽  
K. Iai ◽  
N. Sakaki ◽  
K. Adachi ◽  
...  
Keyword(s):  
Binding Site ◽  
Rotation Speed ◽  
Site Occupancy ◽  
Nucleotide Binding ◽  
Nucleotide Binding Site ◽  
F1 Atpase

Photoaffinity labelling of a low-affinity nucleotide binding site on the β-subunit of yeast mitochondrial F1 -ATPase

FEBS Letters ◽  
1979 ◽  
Vol 108 (1) ◽  
pp. 253-256 ◽  
Author(s):  
Roland Gregory ◽  
Diether Recktenwald ◽  
Benno Hess ◽  
Hans-Jochen Schäfer ◽  
Peter Scheurich ◽  
...  
Keyword(s):  
Binding Site ◽  
Nucleotide Binding ◽  
Nucleotide Binding Site ◽  
Β Subunit ◽  
Photoaffinity Labelling ◽  
F1 Atpase

scholarly journals Catalytic Activity of the α3β3γ Complex of F1-ATPase without Noncatalytic Nucleotide Binding Site

1997 ◽  
Vol 272 (13) ◽  
pp. 8215-8221 ◽  
Author(s):  
Tadashi Matsui ◽  
Eiro Muneyuki ◽  
Masahiro Honda ◽  
William S. Allison ◽  
Chao Dou ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Binding Site ◽  
Nucleotide Binding ◽  
Nucleotide Binding Site ◽  
F1 Atpase

scholarly journals Antagonistic Regulation of Native Ca2+- and ATP-sensitive Cation Channels in Brain Capillaries by Nucleotides and Decavanadate

2004 ◽  
Vol 123 (6) ◽  
pp. 743-757 ◽  
Author(s):  
László Csanády ◽  
Vera Adam-Vizi
Keyword(s):  
Binding Site ◽  
Nucleotide Binding ◽  
Nucleotide Binding Site ◽  
Cation Channels ◽  
Closed Channel ◽  
Open Probability ◽  
Inhibitory Potency ◽  
High Affinity ◽  
Capillary Endothelial Cells ◽  
Atp Inhibition

Regulation by cytosolic nucleotides of Ca2+- and ATP-sensitive nonselective cation channels (CA-NSCs) in rat brain capillary endothelial cells was studied in excised inside-out patches. Open probability (Po) was suppressed by cytosolic nucleotides with apparent KI values of 17, 9, and 2 μM for ATP, ADP, and AMP, as a consequence of high-affinity inhibition of channel opening rate and low-affinity stimulation of closing rate. Cytosolic [Ca2+] and voltage affected inhibition of Po, but not of opening rate, by ATP, suggesting that the conformation of the nucleotide binding site is influenced only by the state of the channel gate, not by that of the Ca2+ and voltage sensors. ATP inhibition was unaltered by channel rundown. Nucleotide structure affected inhibitory potency that was little sensitive to base substitutions, but was greatly diminished by 3′-5′ cyclization, removal of all phosphates, or complete omission of the base. In contrast, decavanadate potently (K1/2 = 90 nM) and robustly stimulated Po, and functionally competed with inhibitory nucleotides. From kinetic analyses we conclude that (a) ATP, ADP, and AMP bind to a common site; (b) inhibition by nucleotides occurs through simple reversible binding, as a consequence of tighter binding to the closed-channel relative to the open-channel conformation; (c) the conformation of the nucleotide binding site is not directly modulated by Ca2+ and voltage; (d) the differences in inhibitory potency of ATP, ADP, and AMP reflect their different affinities for the closed channel; and (e) though decavanadate is the only example found to date of a compound that stimulates Po with high affinity even in the presence of millimolar nucleotides, apparently by competing for the nucleotide binding site, a comparable mechanism might allow CA-NSC channels to open in living cells despite physiological levels of nucleotides. Decavanadate now provides a valuable tool for studying native CA-NSC channels and for screening cloned channels.

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