Structural Characterization of the Interaction of the and Subu

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• 作者：Stephan Wilkens ; Dan Borchardt ; Joachim Weber ; and Alan E. Senior
• 刊名：Biochemistry
• 出版年：2005
• 出版时间：September 6, 2005
• 年：2005
• 卷：44
• 期：35
• 页码：11786 - 11794
• 全文大小：748K
• 年卷期：v.44,no.35(September 6, 2005)
• ISSN：1520-4995

文摘

A critical point of interaction between F₁ and F₀ in the bacterial F₁F₀-ATP synthase is formedby the and subunits. Previous work has shown that the N-terminal domain (residues 3-105) of the subunit forms a 6 -helix bundle [Wilkens, S., Dunn, S. D., Chandler, J., Dahlquist, F. W., and Capaldi,R. A. (1997) Nat. Struct. Biol. 4, 198-201] and that the majority of the binding energy between andF₁ is provided by the interaction between the N-terminal 22 residues of the - and N-terminal domain ofthe subunit [Weber, J., Muharemagic, A., Wilke-Mounts, S., and Senior, A. E. (2003) J. Biol. Chem.278, 13623-13626]. We have now analyzed a 1:1 complex of the -subunit N-terminal domain and apeptide comprising the N-terminal 22 residues of the subunit by heteronuclear protein NMR spectroscopy.A comparison of the chemical-shift values of -subunit residues with and without N-terminal peptidebound indicates that the binding interface on the N-terminal domain of the subunit is formed by helices I and V. NOE cross-peak patterns in 2D ¹²C/¹²C-filtered NOESY spectra of the ¹³C-labeled -subunitN-terminal domain in complex with unlabeled peptide verify that residues 8-18 in the -subunit N-terminalpeptide are folded as an helix when bound to N-terminal domain. On the basis of intermolecularcontacts observed in ¹²C/¹³C-filtered NOESY experiments, we describe structural details of the interactionof the -subunit N-terminal domain with the -subunit N-terminal helix.