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Assessment of DNA Contamination in RNA Samples Based on Ribosomal DNA
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青緑の藻類アグメンレルム・クアドルプリカタム (agmenellum quadruplicatum) には,共振的に閉じられたDNAの円が含まれています
Cell
|December 1, 1976
まとめ
研究者らは,青緑藻の円形DNAを初めて可視化しました. Agmenellum quadruplicatumのこれらの円形のDNA分子は,300万から8000万ダルトンまでの範囲にあります.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- シアノバクテリアとも呼ばれる青緑藻は,複雑な遺伝物質を持っています.
- 以前の研究では,プロカリオットの染色体外DNA要素の存在を暗示していた.
研究 の 目的:
- 青緑藻の共振的に閉ざされた円形のDNAの最初の直接的な視覚化と特徴付けを行う.
- これらの円形のDNA分子のサイズ範囲と性質を決定する.
主な方法:
- Agmenellum quadruplicatumの細胞溶解液が準備されました.
- DNAは,CsCl-エチジウムブロミド密度グラデーションを用いて分断された.
- 分析には電子顕微鏡とアガロゼゲル電泳を用いた.
主要な成果:
- 円形のDNA分子をコヴァレンティックに閉じ,視覚化することが成功しました.
- 円形のDNAの小さな帯が分離され,分析されました.
- 円形のDNA分子は3x10^6から65-80x10^6ダルトンまでの離散的なサイズクラスで構成されています.
結論:
- この研究は,Agmenellum quadruplicatum.で共振的に閉じられた円形DNAの最初の直接的な証拠を提示しています.
- 青緑藻におけるこれらの円形のDNA要素の正確な生物学的な機能は,まだ解明されていない.
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