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

J. Biol. Chem., Vol. 276, Issue 48, 44751-44756, November 30, 2001

This Article Full Text Full Text (PDF) All Versions of this Article: 276/48/44751    most recent M108729200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map 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 Chen, Q. Articles by Amster-Choder, O. Search for Related Content PubMed PubMed Citation Articles by Chen, Q. Articles by Amster-Choder, O. Social Bookmarking                      What's this?

A Novel Sugar-stimulated Covalent Switch in a Sugar Sensor^*

Qing Chen, Anat Nussbaum-Shochat, and Orna Amster-Choder

From the Department of Molecular Biology, The Hebrew University-Hadassah Medical School, P. O. Box 12272, Jerusalem 91120, Israel

The bgl sensory system is composed of a membrane-bound sugar sensor, BglF, and a transcriptional regulator, BglG. The sensor BglF has several enzymatic activities: in its nonstimulated state, it acts as BglG phosphorylase; in the presence of -glucoside in the growth medium, it acts as BglG dephosphorylase and as the -glucoside phosphotransferase. The same active site on BglF, Cys-24, is responsible for the phosphorylation of both the stimulating sugar and the BglG protein. BglF is composed of three domains, two hydrophilic and one hydrophobic. Our previous results suggested that catalysis of the sugar-stimulated functions depends on specific interactions between the B domain, which contains the active site cysteine, and the integral membrane C domain. We report here that the stimulating sugar triggers the formation of a disulfide bond between the active site cysteine and another cysteine in the membrane-embedded domain of BglF. Inability of a mutant BglF protein to form the disulfide bridge between the B and C domains correlates with its inability to catalyze the sugar-stimulated functions. The ability of the cysteine residue in BglF to bind covalently either to a phosphoryl group or to another cysteine residue, depending on the protein stimulation state, suggests a novel way to control signaling by alternative bond formation.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				G. Monderer-Rothkoff and O. Amster-Choder Genetic Dissection of the Divergent Activities of the Multifunctional Membrane Sensor BglF J. Bacteriol., December 1, 2007; 189(23): 8601 - 8615. [Abstract] [Full Text] [PDF]

				S. Yagur-Kroll and O. Amster-Choder Dynamic Membrane Topology of the Escherichia coli {beta}-Glucoside Transporter BglF J. Biol. Chem., May 13, 2005; 280(19): 19306 - 19318. [Abstract] [Full Text] [PDF]

				L. Lopian, A. Nussbaum-Shochat, K. O'Day-Kerstein, A. Wright, and O. Amster-Choder The BglF sensor recruits the BglG transcription regulator to the membrane and releases it on stimulation PNAS, June 10, 2003; 100(12): 7099 - 7104. [Abstract] [Full Text] [PDF]