論文 - 詳細
| RRC ID | 3339 |
|---|---|
| 著者 | Tamura H, Yamada A, Kato H. |
| タイトル | Identification and characterization of a dextranase gene of Streptococcus criceti. |
| ジャーナル | Microbiol Immunol |
| Abstract |
The dextranase gene, dex, was identified in Streptococcus criceti strain E49 by degenerate PCR and sequenced completely by the gene-walking method. A sequence of 3,960 nucleotides was determined. The dex gene encodes a 1,200-amino acid protein, which has a calculated molecular mass of 128,129.91 and pI of 4.15 and is predicted to be a cell-surface protein. The deduced amino acid sequence of dex showed homology to S. downei dextranase (63.9% identity). Phylogenetic analysis revealed the similarity of the deduced amino acid sequence of dextranases in S. criceti, S. sobrinus, and S. downei. A recombinant form of the protein with six histidine residues tagged in the C-terminus was partially purified and showed dextranase activity on blue-dextran sodium dodecyl sulfate-polyacrylamide gel electrophoresis (BD-SDSPAGE) followed by renaturation. We also detected dextranase activity in S. criceti cell extracts and culture supernatant by renatured BD-SDS-PAGE, whereas no dextranase activity of the cells was observed on blue-dextran brain heart infusion (BD-BHI) agar plates. Furthermore, PCR-based mutations of dextranase indicated that a deletion mutant of the C-terminal region could hydrolyze blue dextrans and that the D453E mutation, W793L mutation, and double mutations (W793L and deletion of the C-terminal region) resulted in a loss of dextranase activity. These findings suggest that Asp-453 and Trp-793 residues of S. criceti dextranase are critical to the enzyme's activity. |
| 巻・号 | 51(8) |
| ページ | 721-32 |
| 公開日 | 2007-1-1 |
| DOI | 10.1111/j.1348-0421.2007.tb03961.x |
| PII | JST.JSTAGE/mandi/51.721 |
| PMID | 17704634 |
| MeSH | Amino Acid Sequence Base Sequence Cloning, Molecular Dextranase / genetics* Dextranase / metabolism Dextrans / chemistry Electrophoresis, Polyacrylamide Gel Molecular Sequence Data Mutagenesis, Site-Directed Phylogeny Polymerase Chain Reaction Streptococcus / enzymology* Streptococcus / genetics |
| IF | 1.566 |
| 引用数 | 4 |
| WOS 分野 | IMMUNOLOGY MICROBIOLOGY |
| オルトメトリクス指標 |
オルトメトリクス指標項目
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| 最多言及媒体 | Patent(IFI CLAIMS) |
| 各媒体での言及数の合計 | 1 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 原核生物(大腸菌) | CV-25(DH5alpha) |