Structural and Functional Features of the
Escherichia coli
F
1
-ATPase |
| |
Authors: | Gerhard Grüber |
| |
Institution: | (1) Fachbereich Biologie/Chemie, Abteilung Zoophysiologie, Universität Osnabrück, D-49069 Osnabrück, Germany |
| |
Abstract: | The structural organization and overall dimensions of the Escherichia coli F1-ATPase in solutionhas been analyzed by synchroton X-ray scattering. Using an independent ab initio approach,the low-resolution shape of the hydrated enzyme was determined at 3.2 nm resolution. Theshape permitted unequivocal identification of the volume occupied by the 3 3 complex ofthe atomic model of the ECF1-ATPase. The position of the ^ and subunits were found byinteractive fitting of the solution scattering data and by cross-linking studies. Laser-inducedcovalent incorporation of 2-azido-ATP established a direct relationship between nucleotidebinding affinity and the different interactions between the stalk subunits and with the threecatalytic subunits ( ) of the F1-ATPase. Mutants of the ECF1-ATPase with the introductionof Trp-for-Tyr replacement in the catalytic site of the complex made it possible to monitorthe activated state for ATP synthesis (ATP conformation) in which the and subunits arein close proximity to the subunits and the ADP conformation, with the stalk subunits arelinked to the subunit. |
| |
Keywords: | F1-ATPase Escherichia coli small-angle X-ray scattering quaternary structure ab initio shape determination disulfide formation |
本文献已被 SpringerLink 等数据库收录! |