転置可能な要素IS50は,転置することなく,大腸菌細胞の成長率を改善します

D L Hartl, D E Dykhuizen, R D Miller

Cell

|December 1, 1983

まとめ

挿入シーケンスIS50Rは,E. coli K12の成長率を1時間あたり約5%向上させます. この成長の利点は,転置とは無関係であり,細菌集団の選択における役割を示唆している.

科学分野:

微生物学微生物学とは
遺伝学遺伝学とは
分子生物学は分子生物学である.

背景:

挿入配列 (IS) は,バクテリアに見られる移動性遺伝要素である.
IS50Rは,Tn5トランポゾンに対するトランポゼーゼとトランポゼーション阻害剤をコードする.
IS要素は宿主細胞の健康状態と進化に影響を与えることができます.

研究の目的:

挿入配列IS50RがEscherichia coli K12の成長速度に及ぼす影響を調査する.
観察された成長の利点は,転置によって媒介されているかどうかを判断する.
バクテリアの集団動態におけるIS50Rの潜在的な役割を理解する.

主な方法:

E. coli K12を用いた連続培養 (ケモスタット) の競争実験
IS50Rコピー番号とゲノム位置を評価するために,細菌クローンの分離と分析.
IS50Rのある細胞とない細胞の成長率の差異の定量化.

主要な成果:

IS50Rは,E. coli K12細胞の成長率を大幅に増加させます.
IS50Rによってもたらされる選択的利点は,平均して1時間あたり約5%です.
ほとんどのIS50R要素は,元のゲノム位置に留まっており,トランポジションが成長促進の主要なメカニズムではないことを示しています.
成長の利点は,コピー数が少ないときのIS50Rコピーの数と相関する.

結論:

IS50Rは,E. coli K12のトランスポーゼーション活動とは無関係に成長の利点を提供します.
観察された効果は,IS50Rが細菌の健康状態に影響を与え,集団におけるそのような要素の初期選択と増殖に役割を果たす可能性があることを示唆しています.

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