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The solution structure of ChaB, a putative membrane ion antiporter regulator from Escherichia coli.

ABSTRACT: BACKGROUND: ChaB is a putative regulator of ChaA, a Na+/H+ antiporter that also has Ca+/H+ activity in E. coli. ChaB contains a conserved 60-residue region of unknown function found in other bacteria, archaeabacteria and a series of baculoviral proteins. As part of a structural genomics project, the structure of ChaB was elucidated by NMR spectroscopy. RESULTS: The structure of ChaB is composed of 3 alpha-helices and a small sheet that pack tightly to form a fold that is found in the cyclin-box family of proteins. CONCLUSION: ChaB is distinguished from its putative DNA binding sequence homologues by a highly charged flexible loop region that has weak affinity to Mg2+ and Ca2+ divalent metal ions.

SUBMITTER: Osborne MJ

PROVIDER: S-EPMC514712 | biostudies-literature | 2004 Aug

REPOSITORIES: biostudies-literature

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The solution structure of ChaB, a putative membrane ion antiporter regulator from Escherichia coli.

Osborne Michael J MJ Siddiqui Nadeem N Iannuzzi Pietro P Gehring Kalle K

BMC structural biology 20040811

<h4>Background</h4>ChaB is a putative regulator of ChaA, a Na+/H+ antiporter that also has Ca+/H+ activity in E. coli. ChaB contains a conserved 60-residue region of unknown function found in other bacteria, archaeabacteria and a series of baculoviral proteins. As part of a structural genomics project, the structure of ChaB was elucidated by NMR spectroscopy.<h4>Results</h4>The structure of ChaB is composed of 3 alpha-helices and a small sheet that pack tightly to form a fold that is found in th ...[more]

PMID: 15306028

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