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

J. Biol. Chem., Vol. 279, Issue 2, 901-909, January 9, 2004

This Article Full Text Full Text (PDF) All Versions of this Article: 279/2/901    most recent M308296200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted 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 Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wu, K.-H. Articles by Tai, P. C. Search for Related Content PubMed PubMed Citation Articles by Wu, K.-H. Articles by Tai, P. C. Social Bookmarking                      What's this?

Cys³² and His¹⁰⁵ Are the Critical Residues for the Calcium-dependent Cysteine Proteolytic Activity of CvaB, an ATP-binding Cassette Transporter^*

Kai-Hui Wu and Phang C. Tai

From the Department of Biology, Georgia State University, Atlanta, Georgia 30303

CvaB, a member of the ATP-binding cassette transporter superfamily, is the central membrane transporter of the colicin V secretion system in Escherichia coli. Cys³² and His¹⁰⁵ in the N-terminal domain of CvaB were identified as critical residues for both colicin V secretion and cysteine proteolytic activity. By inhibiting degradation with N-ethylmaleimide and a mixture of protease inhibitors, a stable wild-type N-terminal domain (which showed cysteine protease activity when activated) was purified. Such protease activity was Ca²⁺- and concentration-dependent and could be inhibited by antipain, N-ethylmaleimide, EDTA, and EGTA. At low concentrations, the Ca²⁺ analogs Tb³⁺ and La³⁺ (but not Fe³⁺) significantly enhanced proteolytic activity, suggesting that the size of the cations is important for activity. Together with comparisons of the sequences of members of the cysteine protease family, these results indicate that Cys³² and His¹⁰⁵ are the critical residues in the CvaB N-terminal domain for the calcium-dependent cysteine protease activity and secretion of colicin V.

Received for publication, July 30, 2003 , and in revised form, October 16, 2003.

^* This work was supported in part by National Institutes of Health Research Grant GM34766 (to P. C. T.) and a research enhancement program grant from Georgia State University. The Georgia State University facilities were supported by the Georgia Research Alliance. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

To whom correspondence should be addressed: Dept. of Biology, Georgia State University, 402 Kell Hall, 24 Peachtree Center Ave., Atlanta, GA 30303. Tel.: 404-651-3109; Fax: 404-651-2509; E-mail: biopct{at}langate.gsu.edu.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				P. A. Zaini, A. C. Fogaca, F. G. N. Lupo, H. I. Nakaya, R. Z. N. Vencio, and A. M. da Silva The Iron Stimulon of Xylella fastidiosa Includes Genes for Type IV Pilus and Colicin V-Like Bacteriocins J. Bacteriol., April 1, 2008; 190(7): 2368 - 2378. [Abstract] [Full Text] [PDF]

				H. Wang, B. Na, H. Yang, and P. C. Tai Additional In Vitro and In Vivo Evidence for SecA Functioning as Dimers in the Membrane: Dissociation into Monomers Is Not Essential for Protein Translocation in Escherichia coli J. Bacteriol., February 15, 2008; 190(4): 1413 - 1418. [Abstract] [Full Text] [PDF]

				W.-P. Tzeng, J. D. Matthews, and T. K. Frey Analysis of rubella virus capsid protein-mediated enhancement of replicon replication and mutant rescue. J. Virol., April 1, 2006; 80(8): 3966 - 3974. [Abstract] [Full Text] [PDF]

				S. Ishii, T. Yano, and H. Hayashi Expression and Characterization of the Peptidase Domain of Streptococcus pneumoniae ComA, a Bifunctional ATP-binding Cassette Transporter Involved in Quorum Sensing Pathway J. Biol. Chem., February 24, 2006; 281(8): 4726 - 4731. [Abstract] [Full Text] [PDF]

				F. Gerard, N. Pradel, and L.-F. Wu Bactericidal Activity of Colicin V Is Mediated by an Inner Membrane Protein, SdaC, of Escherichia coli J. Bacteriol., March 15, 2005; 187(6): 1945 - 1950. [Abstract] [Full Text] [PDF]