Tonight the 2011 General Meeting of the American Society for Microbiology opened with “Microbes Among Us: Marvel or Menace.”
The opening session began with introductions by the current president of the organization, Dr. Bonnie Bassler from Princeton University(one of my personal heroines – so great to see her in person for the first time!). She gave very brief introductions to each of the various award winners this year, many of whom will actually give lectures throughout the meeting at special sessions dedicated to their particular award. It seems quite a few of the awards are sponsored by some of the big vendors at the meeting, and I realize this is not a new concept since awards have almost always been named after those who gave the money to support the award. But for some reason, it bugs me just a little; I start to feel like science is becoming akin to pro-sports where we can’t even watch the game anymore without bombarded with advertising. Pet peeve, I guess.
Dr. Bassler then introduced those members of the Geneal Meeting Program Committee responsible for the new format of the metting and primarily responsible for putting it all together: Dr. Margaret McFalll-Ngai and Dr. Arturo Casadevall. At that point Dr. McFall-Ngai took over the introductions of the night’s speakers.
Sidenote: At this point I was struck by the number/proportion of those names mentioned, whether serving in some major function in the organization or listed among the award winners, who were either currently at or were in the very recent past from ivy league and top tier institutions. I had to wonder whether this was a sort of ‘chicken or the egg’ phenomenon: were these people naturally driven and exceptionally intelligent so that they all over-acheived anyway, or did their being at these types of institutions give them greater visibility and a ‘foot-in-the-door’ with this type of organization? Or maybe a little of both… food for thought.
Dr. Nicole Dubilier from the Max Planck Institute kicked things off with a fascinating talk entitled “The Art of Harnessing Dark Energy: Symbioses Between Chemosynthetic Bacteria and Marine Invertebrates.” Of course deep-sea hydrothermal vents are one of my favorite ecosystems to learn and teach about so I was riveted through her talk. Even so, she really did a nice job with the presentation, neat, clear and stayed on time!
Dr. Dubilier began with her work on deep sea mussels, in which she discovered 2 different bacterial symbionts. The first uses methane and the second uses sulfur for chemical energy to fix carbon (the same way that plants use sunlight to fix carbon). She has some beautiful FISH (Fluorescent In-situ Hybridization) images where you could literally see the bacteria, each tagged with a different color, living within the cells of the tissues of the mussels. Each bacteria was in a different type of tissue!
From these types of images she was also able to see another type of bacteria which she later determined to be a parasite that actually lived within the nucleus of the mussel’s cells. Those cells that were host to either the symbiotic methane oxidizers or sulfur oxidizers, were not also host to the third parasitic bacteria. More work is now underway to determine how the symbiotic bacteria may aid in defending against the parasitic invasions of the third bacteria. (Here’s a link to a 2005 paper on the dual symbiosis in Applied and Environmental Microbiology)
After the initial work with the deep-sea hydrothermal mussels, her work then lead to the discovery of these very same symbionts and the parasitic bacteria in every other species of marine muscle that they’ve been able to study to date.
Dr. Dubilier has also worked extensively with gutless marine oligochaetes – the ocean’s equivalent of earthworms. She discovered that all of these types of marine worms have 5 to 6 co-occurring bacterial symbionts which provide most of their digestive processes, and each worm species has a very specific set of the 5 to 6 bacterial symbionts. These bacteria are located just inside the worm cuticle (a.k.a. skin), but exterior to the worm’s cells (extracellular).
This research was an interesting story in which her work involved extensive study of the proteins and genes expressed by these bacterial symbionts to determine how they were serving the worms, (i.e. what substrates they were utilizing in the environment to create biomass for the worms) then these pathways were verified by environmental measurements. Not so long ago, environmental microbiologists would have taken extensive measurements of the environment to form hypotheses on how the microbial symbionts were serving their host, then probe for genes to verify it. Now, with all the new tools we have available, all the new technology, we arrive at much the same answers, but we do it the other way around.
Overall, some intriguing work on not only host-symbiont interactions, but chemosynthesis as well.
There were two speakers following Dr. Dubilier: Dr. Liping Zhao of Shanghai Jiao Tong University, and Dr. Susan Lindquist from the Whitehead Institute. Dr. Zhao discussed the human gut microbiota and prevention of metabolic diseases, and Dr. Lindquist covered heat-shock proteins and their involvement in prion diseases and heritability. Both were very interesting and I hope to be able to cover at some point in the future, but that’s it for tonight, folks. Tomorrow things start bright an early with an entire session on the aftermath of the Deepwater Horizon.