バンコミシン耐性エンテロコックスの病原性島内の毒性の調節
Nathan Shankar1, Arto S Baghdayan, Michael S Gilmore
1nathan-shankar@ouhsc.eduDepartment of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, PO Box 26901, Oklahoma City, Oklahoma 73190, USA.
Nature
|June 18, 2002
まとめ
研究者らは,一般的な腸内細菌であるEnterococcus faecalisの大きな病原性島を発見しました. この遺伝的要素は,菌株間で微妙に変化し,毒性を調節し,正常な腸機能に欠かせない新しい病気の標的を特定するのに役立ちます.
科学分野:
- 微生物学 微生物学とは
- ゲノミクスゲノミクスとは
- 感染症 感染症は感染症です.
背景:
- 腸内細菌は正常なヒトの腸内細菌の一部である.
- また,病院で発生する感染症の主要な原因であり,多くの場合,抗生物質耐性があります.
- これまでの研究は,この属の病原性島を特定していなかった.
研究 の 目的:
- Enterococcus faecalis.alisの毒性の遺伝的根拠を調査する.
- 新しい毒性の要因と潜在的な治療標的を特定する.
主な方法:
- 2つの異なるEnterococcus faecalis菌株のゲノムシーケンシング (病院発症株と米国初のバンコマイシン耐性分離株)
- 独特の遺伝子要素を特定するための比較ゲノム分析.
- 特定された病原性島内の構造と変化の分析.
主要な成果:
- 大きな (約. 150kb) の病原性の島は,Enterococci.で以前に知られていなかった両方の株で特定されました.
- この島はG+Cの含有量が低く,ターミナルリピートに囲まれています.
- 島内の微妙で高周波の変動は,細菌の毒性を調節する.
- この島には,既知の毒性因子と,非病原性単離体では珍しい新種の遺伝子が含まれています.
結論:
- エントロコックスの病原性の島は,毒性の重要な要因です.
- この島の変異により,菌株が適応し,感染を引き起こします.
- 島の新種の遺伝子は,新しい抗菌薬療法のための潜在的な標的を代表しています.
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