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A new crystal lattice structure of Helicobacter pylori neutrophil-activating protein (HP-NAP).

ABSTRACT: A new crystal lattice structure of Helicobacter pylori neutrophil-activating protein (HP-NAP) has been determined in two forms: the native state (Apo) at 2.20 Å resolution and an iron-loaded form (Fe-load) at 2.50 Å resolution. The highly solvated packing of the dodecameric shell is suitable for crystallographic study of the metal ion-uptake pathway. Like other bacterioferritins, HP-NAP forms a spherical dodecamer with 23 symmetry including two kinds of channels. Iron loading causes a series of conformational changes of amino-acid residues (Trp26, Asp52 and Glu56) at the ferroxidase centre.

SUBMITTER: Tsuruta O

PROVIDER: S-EPMC3274388 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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A new crystal lattice structure of Helicobacter pylori neutrophil-activating protein (HP-NAP).

Tsuruta Osamu O Yokoyama Hideshi H Fujii Satoshi S

Acta crystallographica. Section F, Structural biology and crystallization communications 20120125 Pt 2

A new crystal lattice structure of Helicobacter pylori neutrophil-activating protein (HP-NAP) has been determined in two forms: the native state (Apo) at 2.20 Å resolution and an iron-loaded form (Fe-load) at 2.50 Å resolution. The highly solvated packing of the dodecameric shell is suitable for crystallographic study of the metal ion-uptake pathway. Like other bacterioferritins, HP-NAP forms a spherical dodecamer with 23 symmetry including two kinds of channels. Iron loading causes a series of ...[more]

PMID: 22297984

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The neutrophil-activating Dps protein of Helicobacter pylori, HP-NAP, adopts a mechanism different from Escherichia coli Dps to bind and condense DNA.

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Crystal structure of activated CheY1 from Helicobacter pylori.

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Project description: Not available

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High yield purification of Helicobacter pylori neutrophil-activating protein overexpressed in Escherichia coli.

Project description:BackgroundHelicobacter pylori neutrophil-activating protein (HP-NAP) is involved in H. pylori-induced gastric inflammation. Due to its immunogenic and immunomodulatory properties, HP-NAP has been used for developing vaccines against H. pylori infection and new drugs for cancer therapy.ResultsHere, we provide a simple process for high-yield production of HP-NAP by applying one-step negative chromatography to purify recombinant HP-NAP expressed in Escherichia coli (E. coli). In our E. coli expression system, recombinant HP-NAP constitutes nearly 70% of the total protein. Overexpressed recombinant HP-NAP is almost completely soluble upon cell lysis at pH 9.5. Under the optimal condition at pH 8.0, recombinant HP-NAP with purity higher than 95% can be obtained from E. coli by collecting the unbound fraction using diethylaminoethyl (DEAE) Sephadex resin in batch mode. The overall yield of HP-NAP from a 50-ml E. coli culture is ~19 mg. The purified HP-NAP folds into a multimer with a secondary structure of α-helix and is able to trigger the production of reactive oxygen species by neutrophils.ConclusionsPurification of recombinant HP-NAP overexpressed in E. coli using DEAE Sephadex negative mode batch chromatography is an efficient method for high-yield production of highly pure HP-NAP in its native state. The purified HP-NAP is useful for various clinical applications including vaccine development, diagnosis, and new drug development.

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| S-EPMC3620106 | biostudies-literature

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