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Updated: Sep 9, 2025

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極度の酸性川 (スペインのリオ・ティント) の減少した潮の沈殿物から濃縮された窒素を減少させる微生物によるFe ((II) の酸化に対するpHと塩分の変動の影響

Martina Bottaro¹, Sergey Abramov², Ricardo Amils³

¹Geomicrobiology, Department of Geosciences, University of Tübingen, Germany.

FEMS microbiology ecology

|August 29, 2025

まとめ

リオ・ティントの堆積物におけるFe (II) 酸化 (NRFeOx) と結合した窒素還元は,チオバシルスとデニトロモナスによって引き起こされる. pHや塩分などの環境要因が鉄と窒素の循環に影響を及ぼします

科学分野:

環境微生物学
地化学
バイオジオケミカルサイクル

背景:

Fe ((II)) 酸化 (NRFeOx) と結合した窒素還元は,河口沈殿生物化学における重要なプロセスである.
リオ・ティント川の河口は pH と塩分が変動し,微生物のプロセスに影響を及ぼします.
関連する微生物とその環境の許容量を理解することは,この環境におけるNRFeOxにとって極めて重要です.

研究の目的:

Río Tintoの堆積物からNRFeOxを吸収できる微生物を濃縮し,特定する.
NRFeOxの微生物活動に対するpHと塩分変動の影響を調査する.
異なる河口条件下での主要なFe (II) 酸化経路を決定する.

主な方法:

ニットレート/Fe (II) またはアセテート/ニットレート/Fe (II) で修正された堆積物による微小宇宙実験.
アセテート/ニートレート/Fe (II) で修正された媒質を用いた濃縮培養.
16S rRNA遺伝子の豊富な分析により,微生物群を特定する.
微生物の塩分とpHに対する耐性を試す

主要な成果:

ティオバシルスとデニトロモナスはNRFeOxの主要因子として特定されました.
微生物のNRFeOxはpHと塩分度などの環境パラメータによって影響を受けた.
沈殿物のバッファリング能力とアセテットの利用可能性は,酸性低潮時のNRFeOxをサポートしました.
高塩分 (高潮) の条件下では,化学窒素化が支配的なFe (II) 酸化経路であることが判明した.

結論:

ThiobacillusやDenitromonasのような特定の微生物は,Río Tintoの堆積物の中でNRFeOxを駆動しています.
環境の変動はNRFeOx微生物群とその機能に大きく影響する.
アセテットの利用可能性と沈殿物のバッファリングは,環境ストレス中にNRFeOxを維持するために不可欠です.

キーワード:

デニトロモンチオバシルス NRFeOx微生物リオ・ティントの潮堆積物減少した堆積層の微生物コミュニティ

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