How bacteria strategize together on how to ‘take down’ their host
Elegant systems of bioluminescence
Symbiotic relationships between organisms
Cells speak multiple languages
Enjoy this remarkable presentation. And a sincere thanks to Patrik Beno for sharing it with me.
Perry Marshall
　
http://www.cosmicfingerprints.com/blog/intelligent-bacteria/

This is really incredible. Where did the proposed bacterial molecular codes come from?

“Benner suggests tiny pores in rocks that would be too big for bacteria.” Don’t you mean, “…too small for bacteria”?

You might want to correct spelling in this sentence: “One possibile alternative is that…”

[CZ: Thanks, thanks--fixed, fixed]

This is wrong. The bacteria were always grown in phosphate — the “non-phosphate” media had 3 uM phosphate contamination, as the authors acknowledge in the text. This phosphate contamination is one reason why many scientists do not believe this paper at all.

The microbiologist Rosie Redfield has published a devastating critique of this paper:

http://rrresearch.blogspot.com/2010/12/arsenic-associated-bacteria-nasas.html

[CZ: Thanks--I will rein in the figurative language. And I highly recommend Redfield's post.]

How does this rule out silicon-based life? (I say this as a complete non-biologist.) We had life on Earth long before any significant amount of atmospheric oxygen, so I would assume such life didn’t need much CO2 transport.

http://www.monobasinresearch.org/index.html

@ Mehkong Kurt:

there as been speculation for decades about silicon-based life

Perhaps in scifi; SiO2 being solid pretty much torpedoes the idea among scientists AFAIU.

I would like to clarify one point you make about Mono Lake:

“One of these expeditions was to Mono Lake, a practically toxic body of water. It’s very salty, very alkaline, and is steeped in arsenic.”

Arsenic exists in many forms, and not all are equally toxic to all life, nor are the type and/or concentrations in the water column such that inhibit an astonishingly productive ecosystem. Mono’s (pronounced Moe’-no) average annual primary productivity is 686 gC/m2-yr, and it often exceeds 1000 gC/m2-yr. The lake supports not only algae but trillions of brine shrimp and a massive population of alkali flies, in turn supporting millions of migratory and resident birds.

The lake’s microbial life has only recently received attention since about the time NASA first used the lake as a test bed for robotic Mars missions in 1995. The bacterium and viruses in the lake, in its seeps and springs, in its anoxic depths, and around brackish lagoons, present a great frontier of weird and unknown. It’s a micro-wilderness.

As Dr. Wolfe-Simon pointed out, the story is not about Mono Lake, but I did want to clarify that Mono is far from being a toxic body of water.

[CZ: Thanks! I'll revise that part of the post.]

It seems to me that the amazing thing is that the bacteria stay alive under these conditions.

That was my thought behind my question: “at that point where the normal bacteria were (would be) near death, what was different with the way the Mono Lake bacteria were (would be) incorporating the As?”

If I were raising something in captivity in my laboratory, I think I would attempt to feed it what I thought it wanted to eat. Why did the researchers start out with pure phosphate rather than arsenate or an exact match to the Mono Lake brine if these bacteria are supposed to be arsenic based life?

If I wanted to compare how the Mono Lake bacteria handled arsenate differently than normal strains, I think I might start both strains on phosphate and increase the arsenate. Can the non Mono Lake bacteria adapt? Or, at that point where the normal bacteria were near death, what was different with the way the Mono Lake bacteria were incorporating the As? Do normal bacteria end up with As distributed throughout? Wouldn’t this help answer the sequestration vs assimilation question raised above?

[CZ: Here is my non-biologist answer: These bacteria are not, despite some news reports this week, arsenic-based life. On Mono Lake, they are ordinary, phosphate-based life. But, perhaps due to their high tolerance for arsenic, they can swap arsenic for phosphate in an experiment--at least according to the scientists. As for your second question, arsenic is toxic to most organisms, including bacteria, and they have mechanisms to get rid of it from their system. Some have better mechanisms than others. And some bacteria at Mono Lake can even feed on arsenic: http://www.ncbi.nlm.nih.gov/pubmed/20511421. The bacteria in this paper were not dying off from arsenic poisoning--they were growing on pure arsenic and no phosphate (assuming there was no contamination).]

Have non-Mono Lake bacteria been tested? How would a “normal” bacterial strain cope with increasing As?

At any rate, it seems to me that the fact the chemistry of the lake has not been consistent over time would be relevant.

Sveny does not understand DNA, how cute.

? Directed at me? What’s it supposed to mean?