アーケアは,土壌のアンモニア酸化プロカリオートの中で優勢です
S Leininger1, T Urich, M Schloter
1Department of Biology, University of Bergen, Jahnebakken 5, N-5020 Bergen, Norway.
Nature
|August 18, 2006
まとめ
古代のアンモニア酸化物質は,細菌性よりも土壌に大幅に豊富に存在し,窒素循環において重要な役割を果たしています. この発見は,土壌の生態系とアンモニアの酸化プロセスにおける彼らの優位性を強調しています.
科学分野:
- 微生物学 微生物学とは
- 環境科学 環境科学
- バイオジオケミストリー バイオジオケミストリー
背景:
- アンモニアの酸化により,世界の窒素循環における重要なプロセスである窒化が始まります.
- 窒素の利用可能性は植物栄養に影響を与え,浸出による地下水の汚染につながる可能性があります.
研究 の 目的:
- 土壌生態系における古代アンモニア酸化物質の豊富さを調査する.
- 古代のアンモニア酸化物質の豊富さを,その細菌の同類と比較するために.
主な方法:
- 12種類の土壌でアンモニアモノオキシゲネーゼ (amoA) 遺伝子の豊富さを調査しました.
- バイオマーカーとしてCrenarchaeota特有の脂質 (Crenarchaeolなど) を利用した.
- 活動と豊富性の分析のためのリバーストランスクリプション定量PCRとパイロシーケンシングの採用.
主要な成果:
- 考古アモア遺伝子の複製は,バクテリアのアモア遺伝子よりも3000倍も多い.
- 古代アモア遺伝子の豊富さは,クレナルカイオタ特有の脂質と相関しています.
- 古代生物の in situ 活動が示され,その数値的優位性を確認した.
結論:
- 古代アンモニア酸化物質は,土壌生態系において数値的に優位である.
- Crenarchaeotaは,地上の環境における主要なアンモニア酸化生物である可能性が高い.
- これは,窒素循環と土壌の微生物生態学を理解する上で重要な意味を持つ.
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