血流とダニに関連した変異体との比較で,再発性発熱細菌の変異体です
1Laboratory of Microbial Structure and Function, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA. tom_schwn@nih.gov
まとめ
ボレリア・ヘルムシー (Borrelia hermsii) は,再発性熱のスパイロケータで,哺乳類とダニの宿主間で表面タンパク質 (Vmps) を交換する. この現象的なスイッチは温度に依存し,逆行性があり,宿主の適応を助けます.
科学分野:
- 微生物学 微生物学とは
- 寄生虫学とは,寄生虫学である.
- ベクトル媒介性疾患は,ベクトル媒介性疾患である.
背景:
- Borrelia hermsiiは,哺乳類の宿主とのベクトル間のサイクルを繰り返す再発性発熱スパイロケートです.
- ホストに関連したフェノタイプの変化を理解することは,病原体の伝播と生存を理解するために不可欠です.
研究 の 目的:
- Borrelia hermsiiが,異なる宿主体において,その生命周期中に表型的変化を経験するかどうかを調査する.
- ホストの適応とそれらの調節に関与する特定の表面タンパク質を特定する.
主な方法:
- 感染したマウスのBorrelia hermsii (血清型7または8) を感染したオルニソドロス・ヘルムシのダニを感染させる.
- ティックとマウスのスパイロケタル変性メジャータンパク質 (Vmps) の変化をモニタリングする.
- 温度を変えることで,体内のフェノタイプスイッチを誘導する.
主要な成果:
- ティックの感染時に,Borrelia hermsiiは,血清型特異のVmps (7または8) をダウンレギュレーションし,Vmp33をアップレギュレーションした.
- ティックに関連したフェノタイプへのこの切り替えは,温度を下げることで文化で複製することができます.
- ネズミへの伝播はプロセスを逆転させ,スパイロケテスは元のVmps.の表現を再開しました.
結論:
- Borrelia hermsiiは宿主依存のフェノタイプの可塑性を発揮し,哺乳類とダニの宿主間のVmp発現を切り替える.
- 温度は,このVmpスイッチを調節する重要な環境シグナルであり,ベクトルへの適応を容易にします.
- この現象的変化の可逆性は,スパイロケータの伝播への適応性を強調しています.
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