HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ida, K. Articles by Futai, M. Search for Related Content PubMed PubMed Citation Articles by Ida, K. Articles by Futai, M. Social Bookmarking                      What's this?

J. Biol. Chem., Vol. 266, Issue 9, 5424-5429, 03, 1991

Catalytic site of F1-ATPase of Escherichia coli. Lys-155 and Lys-201 of the beta subunit are located near the gamma-phosphate group of ATP in the presence of Mg2+

K Ida, T Noumi, M Maeda, T Fukui and M Futai
Department of Organic Chemistry and Biochemistry, Osaka University, Japan.

The catalytic site of Escherichia coli F1 was probed using a reactive ATP analogue, adenosine triphosphopyridoxal (AP3-PL). For complete loss of enzyme activity, about 1 mol of AP3-PL bound to 1 mol of F1 was estimated to be required in the presence or absence of Mg2+. About 70% of the label was bound to the alpha subunit and the rest to the beta subunit in the absence of Mg2+, and the alpha Lys-201 and beta Lys-155 residues, respectively, were the major target residues (Tagaya, M., Noumi, T., Nakano, K., Futai, M., and Fukui, T. (1988) FEBS Lett. 233, 347-351). Addition of Mg2+ decreased the AP3-PL concentration required for half-maximal inhibition, and predominant labeling of the beta subunit (beta Lys-155 and beta Lys-201) with the reagent. ATP and ADP were protective ligands in the presence and absence of Mg2+. The alpha subunit mutation (alpha Lys-201----Gln or alpha Lys-201 deletion) were active in oxidative phosphorylation. However, purified mutant F1s showed impaired low multi-site activity, although their uni-site catalyses were essentially normal. Thus alpha Lys-201 is not a catalytic residue, but may be important for catalytic cooperativity. Mutant F1s were inhibited less by AP3-PL in the absence of Mg2+, and consistent with this, modifications of their alpha subunits by AP3-PL were reduced. AP3-PL was more inhibitory to the mutant enzymes in the presence of Mg2+, and bound to the beta Lys-155 and beta Lys-201 residues of mutant F1 (alpha Lys-201----Gln). These results strongly suggest that alpha Lys-201, beta Lys-155, and beta Lys-201 are located close together near the gamma-phosphate group of ATP bound to the catalytic site, and that the two beta residues and the gamma-phosphate group become closer to each other in the presence of Mg2+.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				Y. Iko, Y. Sambongi, M. Tanabe, A. Iwamoto-Kihara, K. Saito, I. Ueda, Y. Wada, and M. Futai ATP Synthase F1 Sector Rotation. DEFECTIVE TORQUE GENERATION IN THE beta SUBUNIT SER-174 TO PHE MUTANT AND ITS SUPPRESSION BY SECOND MUTATIONS J. Biol. Chem., December 7, 2001; 276(50): 47508 - 47511. [Abstract] [Full Text] [PDF]

				H. Omote, N. P. Le, M.-Y. Park, M. Maeda, and M. Futai betaSubunit Glu-185 of Escherichia coli H[IMAGE]-ATPase (ATP Synthase) Is an Essential Residue for Cooperative Catalysis J. Biol. Chem., October 27, 1995; 270(43): 25656 - 25660. [Abstract] [Full Text] [PDF]