Pelagibacterales -- Nothing To Do WIth The Bakken -- May 30, 2020

First things first: SpaceX Falcon 9 will try again today: 3:22 p.m. EDT or 2:22 p.m. CDT. This will be SpaceX' first attempt to send astronauts to infinity and beyond. Just kidding. They will go only as far as the international space station. By the way, I was not aware how "big" the international space station really is. It's huge. Lego has an international space station model and it includes the space shuttle. The space station absolutely dwarfs the space shuttle.

The Original Post

The technology today is simply incredible, and what students know by eighth grade far exceeds what we knew when I was starting college.

This was brought home to me yesterday (again) when Arianna, our oldest granddaughter, senior in high school, and I were talking about chemistry, her favorite science subject, but not her favorite subject. Her favorite subjects are drama and poetry. But I digress.

We were able to discuss atoms, neutrons, protons, electrons, etc., asking ourselves questions and coming to some sort of answer based on things she already knew and things that I did not know when I was taking high school chemistry. "Knowing" stuff makes it so much easier than simply memorizing stuff when trying to understand things.

One of things I have done over the years is keep lists of words that I come across when reading. These are words that are new to me; words I should know but don't; words that I think Arianna should know; words that seem interesting; etc. I simply list them with minimal categorization. 

At the sidebar at the right, I have a link to Watts Up With That and every two or three days I check in on that site to scroll through the stories that have appeared since I last checked in. I happened to catch an article on bacteria in the ocean. The article did not interest me much but the name of the bacteria caught my attention. From the article:

University of Washington oceanographers discovered that the bacteria that dominate seawater, known as Pelagibacter or SAR11, hosts a unique virus.

With SARS and corona virus in the news, I was struck by "SAR 11."

But even more so, I was struck by it's "common" name: Pelagibacter.

One of the first words ever I put on Arianna's word list was pelagic, which means far out at sea. I first came across the word when Arianna and I were studying birds and read that the albatross was unique in being one of the few (only?) true pelagic birds. What a great word to know.

So, then, after all these years -- I probably started the vocabulary lists four years ago -- I come across "pelagic" again -- "Pelagibacter."

But first I googled "SAR11 bacterial."

The search takes me to "Pelagibaterales."  And then that took me to "streamlining theory."

Genomic streamlining is a theory in evolutionary biology and microbial ecology that suggests that there is a reproductive benefit to prokaryotes having a smaller genome size with less non-coding DNA and fewer non-essential genes.

There is a lot of variation in prokaryotic genome size, with the smallest free-living cell's genome being roughly ten times smaller than the largest prokaryote.

Two of the bacterial taxa with the smallest genomes are Prochlorococcus and Pelagibacter ubique, both highly abundant marine bacteria commonly found in oligotrophic regions.

Similar reduced genomes have been found in uncultured marine bacteria, suggesting that genomic streamlining is a common feature of bacterioplankton. This theory is typically used with reference to free-living organisms in oligotrophic environments.

And then that took me full circle back to corona virus which is very, very "streamlined" with only eight genes, if I recall correctly. Macht nichts.

But then look at that! A new word to add to Arianna's list: oligotrophic.

Examples of oligotrophic organisms are the cave-dwelling olm; the bacterium, Pelagibacter ubique, which is the most abundant organism in the oceans with an estimated 2 × 1028 individuals in total; and the lichens with their extremely low metabolic rate. 

Until today I had never heard of pelagic bacteria, now it seems to pop up everywhere. But the point is that students starting off in college these days know so much more and have access to so much more that I ever did.

I post the vocabulary lists that I give to Arianna over at my literature blog. Here is the link to the first list that included pelagic. I think my library of words has grown to seven lists, and continues grow.

By the way, riparian is on the list and I first came across that list because of the Bakken.

By the way, where did "SAR" come from in this case? From microbewiki:

The order was originally named SAR11 following its discovery in the Sargasso Sea in 1990 by Professor Stephen Giovannoni and colleagues, from Oregon State University.

It was first placed in the order of Rickettsiales, but after rRNA gene-based phyogenetic analysis, in 2013 it was raised to the rank of order, and then placed as sister order to the Rickettsiales in the subclass Rickettsidae. They are most closely related to the their sister order, the Rickettsiales. 

The Sargasso Sea is important for this reason: that's where American eels spawn. And that was not known until very, very recently. That spawned (pun intended) an entire book on the American eel.

American eels are the only species of freshwater eel found in North America. ... Eels have a complex lifecycle that begins far offshore in the Sargasso Sea where adults spawn. After eggs hatch, young eels drift inland with ocean currents into streams, rivers and lakes for over 3,700 miles. This journey may take many years.

From microbewiki and the Sargasso Sea:

One of the documented most abundant microbes of the marine world, as well as the Sargasso Sea, belongs to the clade of SAR11 α – proteobacteria.

The name “Sar” was given to this family of bacteria due to their discovery in the Sargasso Sea in 1990.

One species that is of most interest to researchers is that of Pelagibacter ubique. P. ubique covers 30% of the surface in the Sargasso. During the summer months the population of this bacterium can cover up to 50% of the ocean’s surface weighing more than the weight of all of the fish in the all of the collective oceans.

What make these bacteria an interest of research, is its ability to thrive in an environment low in nutrients and resources. This bacterium can surprisingly replicate efficiently in a low nutrient environment and is one of the smallest self-replicating cells found.

Evolutionary genome reduction has been observed in this microbe. This is consistent with the hypothesis of “genome streamlining driven by selection acting on a very large population which resides in a very low nutrient habitat.”

The belief is that the bacterium’s genome is being reduced so not to expend energy on replicating DNA with no adaptive value. This saves the the organism from performing unnecessary metabolic tasks

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Naomi Seibt vs St Greta

From Not A Lot of People Know That: well, isn't this interesting? And at wiki.