まとめ
アイソポッドやアンフィポッドを含む特定の甲殻類には腸内微生物が欠けている. しかし,彼らの外骨格は, termite hindguts と異なり,密集した細菌のコミュニティをホストしています.
科学分野:
- マリン・バイオロジーの海洋生物学
- 甲殻類の生理学について
- 微生物学 微生物学とは
背景:
- 多くの動物の消化器系は,共生微生物に依存しています.
- 木を掘る甲殻類は,特殊な消化適応で知られている.
- 以前の研究は,特定の甲殻類種の消化管内の微生物の存在を広範に調査していなかった.
研究 の 目的:
- 選択された木を掘り起こし,木を棲む甲殻類の消化道に微生物が存在するか否かを調査する.
- 消化管のルメンの微生物群と,外骨格の表面にある微生物群を比較する.
- 木を食する生態系における甲殻類と微生物の相互作用を理解するためのベースラインを提供すること.
主な方法:
- スキャニング電子顕微鏡 (SEM) を用いて,2つの海洋生物と1つの陸生木を産む同類動物,そして1つの木を棲む両足類の消化管 (in toto) を検査した.
- SEMを用いて,これらの甲殻類の外骨格表面も調査した.
- 比較のために,白のヒンドグート含有量を観察した.
主要な成果:
- すべての研究されたイソポッドおよびアンフィポッド種の消化管は,微生物が全く存在しないことが判明しました.
- これらの甲殻類の外側外骨格の表面には,密度の高い細菌菌群が一貫して観察されました.
- 予想通り, termite hindguts は多様な腸内微生物群を示した.
結論:
- 研究された木を掘るおよび木を居住する甲殻類は,内部微生物共生体を排除するユニークな消化戦略を有しています.
- 外骨格上の外部細菌コミュニティは,内部消化とは異なる役割を果たす可能性があります.
- この発見は, termietのような木を食する他の無脊椎動物で観察された典型的な腸内微生物と対照的です.
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