Exploring Biodiversity: The Search for New Medicines

Lecture 2 – Shedding Light on an Invisible World

by Bonnie L. Bassler, PhD
  1.  1.  Start of Lecture 2
  2.  2.  Welcome by HHMI Vice President Dr. Peter Bruns
  3.  3.  Profile of Dr. Bonnie Bassler
  4.  4.  Hidden biodiversity: the microbes
  5.  5.  Family trees
  6.  6.  Evolutionary trees of related organisms
  7.  7.  Three main branches of life
  8.  8.  Bacteria predominant on Earth
  9.  9.  Bacterial cell structure
  10. 10.  Bacteria traits appear simple
  11. 11.  Bacteria inhabit extreme environments
  12. 12.  Humans are covered in bacteria
  13. 13.  You are mostly bacterial
  14. 14.  Most bacteria are beneficial or neutral
  15. 15.  Pathogenic bacteria
  16. 16.  How can tiny bacteria affect humans?
  17. 17.  A model system to study host-bacterial interaction
  18. 18.  The bobtail squid and bioluminescent bacteria
  19. 19.  Video: Bobtail squid swimming and burrowing
  20. 20.  Bioluminescent bacteria for camouflage
  21. 21.  Daily cycle of bacterial growth in squid
  22. 22.  Q&A: What makes bacteria so resilient?
  23. 23.  Q&A: Can the bacteria live outside the squid?
  24. 24.  Q&A: How do the bacteria get into the squid?
  25. 25.  Q&A: How big is the squid's light organ?
  26. 26.  Q&A: Is the use of antibacterial soap detrimental?
  27. 27.  Q&A: How do bacteria survive in extreme environments?
  28. 28.  Vibrio fischeri only makes light at high cell density
  29. 29.  Quorum sensing and autoinducers
  30. 30.  Vibrio harveyi is not symbiotic
  31. 31.  Demonstration: Glowing bacteria in a flask
  32. 32.  Quorum sensing activates a large network of genes
  33. 33.  Pathogens also use quorum sensing
  34. 34.  QS allow bacteria to act collectively
  35. 35.  Bacteria receive signals by membrane receptors
  36. 36.  Receptors as kinases and phosphatases
  37. 37.  Molecular basis of QS pathway
  38. 38.  QS turns on or off a gene regulator
  39. 39.  Animation: The LUX operon controls light production
  40. 40.  Summary
  41. 41.  Q&A: Can you add autoinducer and make the bacteria glow?
  42. 42.  Q&A: Can Vibrio fischeri make light outside of the squid?
  43. 43.  Q&A: What benefit is there to making light in the ocean?
  44. 44.  Q&A: Can you make a bacteria unable to detect autoinducer?
  45. 45.  Q&A: Does QS lead to specialization of bacteria?
  46. 46.  Closing remarks by HHMI Vice President Dr. Peter Bruns


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