ニトロスピラ菌による完全な窒化
Holger Daims1, Elena V Lebedeva2, Petra Pjevac1
1Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
Nature
|November 27, 2015
まとめ
研究者達が発見した新種の細菌は 完全に窒素化し アモニアを窒素化します この発見は,窒素化が2段階のプロセスであるという長年の見解に異議を唱え,窒素循環におけるニトロスピラの役割を強調しています.
科学分野:
- 微生物学
- 環境科学
- 生物化学
背景:
- ナトリフィケーションは窒素循環に不可欠であり,伝統的に2段階のプロセスとして見られています.
- アンモニアの酸化と窒素の酸化を司る微生物は別物と考えられた.
- 完全な窒素化のエネルギー上の利点は,単一の生物が両方のステップを実行できることを示唆しました.
研究 の 目的:
- 窒素化における 機能的分離の百年のパズルを 調べるために
- 完全に窒素化できる微生物を発見し 培養する
- 完全な窒素化の遺伝的基礎と生態学的意義を理解する.
主な方法:
- ニトロスピラ属の新種の細菌の分離と培養
- 代謝経路を特定するゲノム分析
- 環境サンプルのメタゲノミクス分析
主要な成果:
- ニトロスピラ属の 完全に窒素化する細菌の発見と培養
- ゲノム解析により,この有機体におけるアンモニアとニートリートの酸化経路が明らかになった.
- アンモニア・モノオキシゲナーゼとヒドロキシラミン脱水素酵素の遺伝子は,ニトロスピラと環境のメタゲノムで発見されました.
結論:
- 完全に窒素化するニトロスピラは 確立された2段階の窒素化モデルに挑戦します
- これらの生物は,成長過程で,同時にアンモニアを窒素化して活性化します.
- 完全に窒素化するニトロスピラは,世界の窒素循環微生物のコミュニティで重要な役割を果たしています.
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