Talmudic Question #51
Is it possible that prototypical bacterial endospores (e.g., those of Bacillus subtilis) carry out some metabolic activities, albeit at extremely slow rates?
Other Posts
Of Aerobes and Anaerobes
Noteworthy — When first introduced to microbes, we quickly learn to divide them into aerobes and anaerobes. Then we qualify those titles with modifiers to yield such classes as facultative anaerobes, obligate aerobes and strict anaerobes.
On Shape
by Manuel Sánchez — If there is something that draws attention to the study of eukaryotes it is the enormous diversity of their morphology, from the largest sequoias to the smallest radiolaria. Prokaryotes, on the other hand, seem rather simple and boring. If you open page 109 of the 7th edition of Murray, Rosenthal, and Phaller's "Medical Microbiology" you will find...
Count Your Mushrooms
by Elio — Maybe you have to be a mushroom enthusiast or a fungal ecologist to give this a thought, but counting the number of mushrooms in a tract of forest will not tell you the size of the fungal biomass therein. The mushrooms you see are only the fruit bodies. The whole fungal…
Lingua Franca (Lipid Division)
by Elio — A long, long time ago, a biochemist friend of mine said to me jokingly (I think): "When I hear the word lipid, I reach for my gun!" I'm not sure it was all that funny then, but any attempts at disparaging humor must cease now. A month doesn't go by without a report of a new role that lipids play in essential life processes.
The Oldest Gem Tells its Tale
by Gemma Reguera — Modern Earth is nothing like it was in its early days. Our planet was formed some 4.56 billion years ago when a giant stellar cloud collapsed on itself due its massive size and gravitational force. The explosion also generated the sun and many other planetary bodies, including those that would...
Backstroke Swimming
by Christoph — It is not widely known that sporty bacteria have also mastered the art of backstroke swimming. Among them is Caballeronia insecticola...
since no one's answering I will take a stab at it. The answer has to be yes????
I just saw your Talmudic question on possible slow metabolic activity of bacterial endospores — very interesting question, but also very Talmudic, in that I don't think we can answer it at present, although we can talk about it ad infinitum. We need some new tools to measure the metabolism of single spores, and be sure that the metabolism is enzymatic.
Elio's response:
Peter's comment is a measured, careful response, as expected from a distinguished scientist in the field (and others of course).
Judith's is based on logic. It seems easier to assume that something takes place that that it doesn't, even if proving that the former may be elusive.
Elio, I remember some of the discussion of VERY slow growing microbes within the cracks of halite crystals or within amber inclusions. But I suspect that wasn't directly measured. I like to think of spores like tightly wound springs, ready for activation!
I believe they likely do (some of the time). I seem to recall a poster I just saw at the Prokaryotic Development meeting from Sigal Ben-Yeduda's lab where someone did microarrays on spores of different ages. They found different mRNAs present at different times. Which suggests that some mRNAs are being degraded (possibly enzymatically) and/or some mRNAs are being synthesized (definitely enzymatically). I think these experiments were examining spores only a few days old... but it suggests its possible!
Elio's comment:
Thanks for pointing us in this interesting direction. It suggests — perhaps — that spores may "mature" after being released into the world. Maybe they carry out a limited amount of metabolic activity for a short while. A twilight dream before going to sleep?