How Bacteria Evolved Rotary Motors | Michael Manson

How do bacteria power one of the most sophisticated molecular machines in nature?In this episode, we speak with Dr. Michael Manson, one of the pioneers of bacterial motility research, whose nearly 50-year career has helped uncover how the bacterial flagellar motor works. From the first experiments proving that bacterial flagella rotate to the latest breakthroughs in cryo-EM and single-molecule biology, Manson tells the story of how scientists finally solved the mechanism behind a real working biological motor.We explore how bacteria move through chemotaxis using a biased random walk, why E. coli alternates between running and tumbling, and how individual molecules can control the direction of a spinning flagellum. Manson explains the experiments that showed proton motive force powers the flagellar motor, how the motor’s rotor and stator generate torque, why it can reverse direction almost instantly, and how bacteria adapt to changing environments by dynamically adjusting their molecular machinery.We also discuss ATP synthase, proton gradients, molecular motors, bacterial genetics, cryo-electron microscopy, ion channels, self-assembling protein complexes, nanomachines, and the history of the discoveries that transformed modern microbiology.Whether you’re interested in the bacterial flagellar motor, molecular biology, biophysics, microbiology, ATP synthase, chemotaxis, molecular machines, or the fundamental physics of life, this week we go deep into one of biology’s most remarkable inventions.Follow us for more technical interviews with the world’s greatest scientists:Twitter: https://x.com/632nmPodcastInstagram: https://www.instagram.com/632nmpodcast?utm_source=ig_web_button_share_sheet&igsh=ZDNlZDc0MzIxNw==LinkedIn: https://www.linkedin.com/company/632nm/about/Substack: https://632nmpodcast.substack.com/Follow our hosts!Mikhail Shalaginov: https://www.linkedin.com/in/mikhail-shalaginov/Michael Dubrovsky: https://www.linkedin.com/in/michael-dubrovsky/Xinghui Yin: https://www.linkedin.com/in/xinghui-yin/Subscribe:Apple Podcasts: https://podcasts.apple.com/us/podcast/632nm/id1751170269Spotify: https://open.spotify.com/show/4aVH9vT5qp5UUUvQ6Uf6ORWebsite: https://www.632nm.comTimestamps:00:00 - Intro and Reads02:42 - Biased Random Walk10:27 - Manson's Work with Howard Berg13:24 - Proton Motive Force and Flagellum29:07 - Rotors and Stators of Flagella37:20 - Mot Proteins57:34 - CheY and Changing Direction1:11:48 - Biology and Intelligent Design1:26:52 - Reversing Proton Flow1:29:59 - Life at Low Reynolds Number1:39:15 - Mysteries in the 90s and 2000s1:48:34 - Applications of Understanding the Nanomotor1:58:33 - Flagellar Motor Crash Course2:01:46 - Bacterial Learning and Adaptation2:05:56 - Giving Up on Birds2:14:09 - Caltech2:21:38 - Advice for Young Scientists2:30:02 - Origins of Life2:31:19 - What's Left for the Flagellar Motor?PART 2:2:33:33 - Building the Nanomotor2:39:29 - Other Types of Flagella2:47:06 - MotA and MotB3:07:17 - Reusing Motors Across Biology3:10:13 - Benefits of Being Small3:12:34 - CheY and Changing Direction3:19:39 - How Physics Shapes Evolution