GTR Seminar / Topics in Advanced Biological Science
７月８日（月曜）１６：００から、下記の通りGTR/アドバンス生命理学特論セミナー/EMBO Global Lectureを開催いたします。是非お誘いのうえ、ご参加ください。
演題 ：5:2 molecular motors: from bacterial motility to anti-phage defense
講演者 ：Dr. Nicholas MI Taylor (University of Copenhagen, Denmark)
日時 ：7月8日（月）16:00 ~ 17:30
場所 ：理学部A館222号室
講演言語：英語
連絡先 ：小嶋誠司/理学専攻 生命理学領域 微生物運動グループ
kojima.seiji.z6<at>f.mail.nagoya-u.ac.jp (<at>→@に変換）
演題要旨：
Bacteria move through the rotation of large filaments know as flagella. Flagellar rotary motion is powered by a flagellar motor, driven by stator units (MotAB). The MotAB proteins convert the ion motive force across the bacterial inner membrane into rotation of the filament, but it was not understood how this occurred.
Using cryo-EM we have determined structures of the MotAB complex, which we show has a 5:2 stoichiometry shared across different species. By visualizing MotAB in its plugged, inactive state, as well as mimics of its active state, we come up with models for how torque is generated in the flagellar motors, as well as how direction switching in the flagellar motor occurs (1, 2). We also reveal our recent progress on how ion specificity is obtained and propose a mechanism for how stator units become active upon motor incorporation.
I will also present unpublished results on a newly discovered bacteriophage defense system, Zorya, that uses a 5:2 motor complex to sense bacteriophage infection. Using a combination of structural biology, functional assays, light microscopy and mass spectrometry, we provide novel insight into the unique Zorya mechanism of action. We provide data indicating that Zorya detects phage infection by monitoring integrity of the peptidoglycan layer. Upon phage infection, the ZorAB motor proteins get activated and through a 700 Å long tail locally recruit and activate ZorD nuclease that can degrade the phage genome, halting the infection (3).
References
1) Santiveri et al, Cell 183:244-257 (2020)
2) Hu et al, Nat. Commun. 14:4411 (2023)
3) BioRxiv.
★このセミナーは外国人GTR学生向けGTRシリーズ講義です。それぞれの講義についてレポートを提出し合格した外国人GTR生には、シリーズ講義1ポイントが付与されます。レポートはTACTから提出いただきます。受講を希望する場合はGTR e-ポートフォリオにも登録してください。
登録締め切り：7月4日