Brian writes:

Dear Twim,

Thank you for describing the paper about deep ocean sediment dwelling bacteria. Three aspects of this phenomenal discovery deserve follow-up.

First, in binary fission the original cell is present in daughter cells. That leads some to believe these cells are 101.5 million years old. However each division leads to the synthesis of new proteins, woven into cell walls and enlarging internal material. Since division halves original material, newly synthesized proteins make up half of the daughter cells.

Over millions of years, even a very slow expansion rate will dilute original cellular material to infinitesimal levels. In no way are current bacteria made of proteins that existed 101.5 million years ago. 

Second is the importance that substrate pore size, .02 um, is not only smaller than a bacteria – it is smaller than most phages. Ocean dwelling bacteria mortality is driven by phages, and only a location isolated from parasites would permit their long-term survival.

Third is my question about where the slowly accumulating bacteria populations went. Since they are trapped in the sediment, how can population expansion occur?

Again, thank you for bringing this to my, and other’s, attention.


Phil writes:

Dear Vironauts,

I listened to TwiM #223 concerning the resistance of Yersinia to Doxycycline. That was just some really fantastic insight – I (not a microbiologist) had read that paper and came away with very little. Thanks. 

My thoughts drifted to the resistance of Spirochetes, Borrelia burgdorferi in particular, to Doxycycline.

Granted, Yersinia is not a Spirochete but I suspect that whereas Yersinia forms colonies Borrelia forms harder to treat biofilms and cysts. In general, it would appear that Spirochetes are simply more robust and more difficult to treat.

Could TWiM ever do an entire segment on Borrelia burgdorferi?  Will the human race ever conquer Spirochetes?

I would love to hear your panel discuss the relevance of finding Borrelia in the brains of Alzheimers patients – research which has somewhat dropped off with the retirement of noted Pathologist Dr. Alan B. MacDonald. He would be a great guest along with Professor Holly Ahern, a microbiologist at SUNY Adirondack.


Buffalo NY   -14 F with gale force winds and 7 inches of snow on this beautiful summer day.