Halorubrum lacusprofundi

...[The] microbes were isolated from Deep Lake, a very salty lake in Antarctica. The changes found in proteins from these organisms allow them to work in both cold and salty conditions, when temperatures may be well below the freezing point of pure water...

"In such cold temperatures, the packing of atoms in proteins must be loosened slightly, allowing them to be more flexible and functional when ordinary proteins would be locked into inactive conformations...The surface of these proteins also have modifications that loosen the binding of the surrounding water molecules."

"These kinds of adaptations are likely to allow microorganisms like Halorubrum lacusprofundi to survive not only in Antarctica, but elsewhere in the universe..."

-- Strategies for Mars Survival

Deep Carbon

Less than 10% of the Earth's carbon is in its atmosphere, seawater and top crusts. The rest is locked away or in motion deep underground - a "hidden dimension of the planet as poorly understood as it is profoundly important to life on the surface."  

Carbon in Earth, a new publication by scientists collaborating on the Deep Carbon Observatory, notes that:

Among the gaps in our knowledge of deep carbon relate to the deep biosphere. Remarkable discoveries of subsurface microbial life and associated viruses hint at a surprising hidden diversity, primarily within the microbial domains of archaea and bacteria. [But] surprising discoveries of a rich subsurface community of eukayotes promises an even richer deep taxonomy. These findings, coupled with advances in single-cell genomics, predict a coming decade of extraordinary discovery.

Life in "the world’s largest wetland"

Scientists say they have found bacteria living in the cold and dark deep under half a mile of Antarctic ice, a discovery that might advance knowledge of how life could survive on other planets or moons and that offers the first glimpse of a vast ecosystem of microscopic life in underground lakes in Antarctica.

-- New York Times report

P.S. 8 March Russian scientist claim to have found new kind of bacterial life in Lake Vostok.

"At the bottom of the world we can look through a window into our very distant past"

...Cyanobacteria are resourceful organisms. They produce their own energy using a photosynthesis process similar to plants. Light penetrates through the ice cover and through the water down to the lake floor where the microbes grow. Because of a lack of predation and a lack of disturbance by larger organisms, these microbes grow rampant over any surface that is hospitable for growth (in this case any depth that light can reach).
This type of microbial growth is actually quite common in Antarctic and Arctic lakes. What makes Lake Untersee particularly special is that these microbes form two different types of structures – collections of millions of individuals growing together over thousands of years of layered development.

The microbes of Untersee form two distinct kinds of constructions – pinnacles and cones. Both the pinnacles and cones are types of microbial communities and represent one of the earliest forms of life, present in the fossil record nearly 3.5 billion years ago.

The pinnacles of our lake are small, between one-half inch and six inches tall and dominated by a Leptolyngbya species that is common in Antarctica. The other structures, found nowhere else on present-day earth, are the conical stromatolites. The microbes covering the cones aren’t very thick, roughly half a millimeter, but the dark purple cones can grow higher than one and a half feet. These cones consist predominately of a Phormidium species, and it’s thought that the different microbial species are somehow responsible for the creation of the different structures...

-- Michael Becker

The invisible life of the upper troposphere

In a recent article for New Humanist (also here) I mentioned that researchers have suggested that bacteria not only survive in the harsh, beautiful environment of clouds but thrive and reproduce there. My sources were more than four years old. Recent work appears to have amply corroborated the hypothesis, as Ed Yong writes in an excellent piece:

The sky has a microbiome too, and one that may have a critical role in the creation of weather. When water changes from vapour to liquid, it condenses around microscopic particles in the air. When it freezes into ice, the same thing happens. Without these centres, completely pure water would condense and freeze at much lower temperatures than you’d expect. Dust, soot and sea salt can all act as nuclei for water’s transformations, but so can bacteria. For example, some plant-infecting species have proteins on their surfaces that ice can crystallise upon. Just by floating in the air, species like these could kick-start the births of clouds, raindrops and snow.

Inter-being

There is a Peruvian deity, painted on a clay pot dating from around A.D. 300, believed to be responsible for guarding farms. His hair is made of snakes, entwined in braids, with wings for his headdress. Plants of various kinds are growing out of his sides and back, and a vegetable of some sort seems to be growing out of his mouth. The whole effect is wild and disheveled but essentially friendly. He is, in fact, an imaginary version of a genuine animal...a species of weevil in the mountains of northern New Guinea that lives symbiotically with dozens of plants, growing in the niches and clefts in its carapace, rooted all the way down in its flesh, plus a whole ecosystem of mites, rotifers, nematodes and bacteria attached to the garden.

-- from 'Some biomythology' in Lives of a Cell (1974) by Lewis Thomas.

There is a tendency, Thomas concluded, "for living things to join up, establish linkages, live inside each other...get along, wherever possible." 

His point is  supported by recent discoveries regarding the microbiome. As Carl Zimmer writes in When you swallow a hand grenade, this is an interdependence we’ve been evolving for 700 million years, ever since our early animal ancestors evolved bodies that bacteria could colonize. Even jellyfish and sponges have microbiomes.

Painting the invisible

Watercolor of Mycoplasma mycoides by David S. Goodsell, the Scripps Research Institute.

Section through a eukaryotic cell here.

What in me is dark illumine

East Antarctic ice is gaining mass. The dry valleys remain cold for now so the strange beings, living in a pitch dark lake seven times as salty as the sea, 13 degrees below freezing and buried for 2800 years under 20 metres of ice, probably have a future.

P.S. 2 Dec. Search begins for life in another lake, which has been buried under three kilometres of ice for a million years. 

29,000,000,000,000,000,000,000,000,000

The ocean floor is home to 2.9×10²⁹ single-celled organisms — that's 10 million trillion microbes for every human on the planet — but vast though it is, this figure is only 8% of the previous estimate of 35.5×10²⁹

-- report 

Only 8% of the previous estimate is still plenty (!) and it exists alongside and/or interacts with/supports a huge amount of larger life even in the coldest darkest places. In Antarctic benthos, for example, researchers have found the Polychaete worm Spiophanes tcherniai  at densities 150,000 to 180,000 per square metre. (Hat tip DSN)

Seeing as if for the first time

'Tis not unlikely, but that there may be yet invented several other helps for the eye, as much exceeding those already found, as those do the bare eye, such as by which we may perhaps be able to discover living Creatures in the Moon, or other Planets, the figures of the compounding Particles of matter, and the particular Schematisms and Textures of Bodies.

-- from the Preface to Micrographia by Robert Hooke (1665)  

The image shows spherical colonies of Nostoc commune, a bluegreen alga. A darkfield illumination by Gerd Guenther. It is one of the prize winners in the Olympus BioScapes Digital Imaging Competition.

No man is an island...

...but sometimes it can be helpful to see him that way:

Each person can be viewed as an island-like “patch” of habitat occupied by microbial assemblages formed by the fundamental processes of community ecology: dispersal, local diversification, environmental selection, and ecological drift.

A bug's life

We need a Global Strategy for Microbial Conservation, writes Gareth Griffith.

Some endangered bugs are, shall we say, an acquired taste. For example, a recently discovered anaerobic fungus at risk of extinction before it is even formally described is, apparently, specific to the hindgut of the critically endangered Somali wild ass.

More important, however, are microbially dominated habitats such as certain desert soil crusts, glaciers or unusual geological formations.

Tales from the Crysophere

For literally centuries, polar explorers have been aware that in the springtime the bottom of seasonal sea ice becomes visible discolored. Today we know that what they were seeing is a photosynthesis-based biofilm of grand proportions. By March, when the sun spends enough time above the horizon to initiate the ice-algal bloom, the sea ice cover over the Arctic Ocean alone (sea ice also surrounds Antarctica, of course) extends more than 14 million square kilometers, even in this era of climate-driven reductions in the cryosphere. Only in the last decade, however, have we realized that this highly porous sea ice, flushed at its ice-water interface with seawater from below, is also filled with EPS, the sticky exudates of microscopic algae and bacteria that partially account for their entrapment in the ice as it forms in autumn and through winter. These compounds, which partition into the brine phase of the ice along with the microbes and other “impurities” of seawater, are now understood to serve a myriad of biological functions within the ice, from cryo- and osmoprotection to possible viral defense.

-- from Frost Flowers Come to Life by Jody Deming

'Gaia likes it cold,' said James Lovelock.

'...not as we know it...'

Another strange discovery is a previously unknown Deinococcus — a group of bacteria known as the world's toughest — capable of tolerating γ-ray exposures 5,000 times greater than those survived by any other known organism, despite living 15 metres beneath the permafrost. These levels of radiation have never existed on Earth, so the source of the bacterium's resistance is a mystery. Theories put forth so far include that the microbe had an extraterrestrial origin...[and] at this point, no theory has been discarded.

-- from Antarctic microbes live life to the extreme

Five elephants

You carry more microbes in you this moment than all the people who ever lived. Those microbes are growing all the time. So try to imagine for a moment producing an elephant’s worth of microbes. I know it’s difficult, but the fact is that actually in your lifetime you will produce five elephants of microbes. You are basically a microbe factory.

-- from The Human Lake by Carl Zimmer

Gut bacteria may influence thoughts and behaviour notes the Neurophilosophy Blog, but Mike the Mad Biologist cautions:

It's de rigueur to begin a microbiome talk by stating that ninety percent of the cells in the human body are bacterial. Then there's a statement about how we should regard these microbes as another organ, like your heart or liver. And that's where things go off the rails.

The microbiome is not an organ. Those critters are not your 'friends.' They're not necessarily your 'enemies' either, but many of them function like a protection racket--get rid of them, and really bad news moves in.

'A totally new branch of the tree of life'?

A fourth domain...or even a fifth?

--The paper,  A news report

Little wonders

Two of the stories in the news:

Microbes survive 30,000 years inside a salt crystal

Working as a team, bacteria spin gears

'Escherichia Ophelia'

From Microbial art via Biophemera. The artist is JoWOnder

Touching the world ocean

The sea is largely blue (empty of life) rather than green (full of plants and algae) for several reasons. [1] It has, however, a jelly-like 'skin', a sea-surface microlayer about a hundredth of an inch (0.254mm) thick that contains a 'menagerie of microbes'. As Carl Zimmer reports:

It may be hard to imagine such a fine coat of slime holding together for long on top of the heaving ocean. But Dr. [Oliver] Wurl has found that it is quite durable. “We have collected microlayer samples with wind conditions of 16 to 18 knots,” he said. “It’s not pleasant to be in a small boat at that wind speed. That tells us the microlayer is pretty stable.”

At this microlayer, gases are pulled down from the atmosphere. "It’s the ocean breathing through its skin," says Michael Cunliffe. Zimmer continues:

The 'skin' may play a critical role in the environmental well-being of the planet. Studies have shown that pollutants like pesticides and flame retardants can be trapped in the microlayer.

Footnote

[1] Thomas Sherratt and David Wilkinson summarise an answer in Big Questions in Ecology and Evolution like this:

Much of the world's seawater is too dark for photosynthesis. In the euphotic zone, where there is enough light to support a green sea, other factors come into play. Large 'rooted' plants and macroalgae can only survive in the very small area of the ocean that is shallow enough for them to have access to light while being attached to the seabed, and large plants cannot survive by a floating way of life in most of the ocean, because they will be washed up by wind and currents. The leaves the question of why phytoplankton do not make most of the ocean green? The answer is that most seawater is too low in nutrients needed for their growth; one of the reasons for this impoverishment is the action of the plankton themselves through the biological pump. Physical processes, such as thermal stratification, are also important in maintaining low nutrients in the euphotic zone and may change with alterations to the Earth's climate.

Sherratt and Wilkinson note Alfred Redfield's realisation in the 1930s that ocean organisms themselves are largely responsible for creating the chemical environment in which they live rather than it being merely the background against which they evolve. James Lovelock has described Redfield as a forerunner to Gaia theory.

P.S. 29 July: a mechanism is proposed for "how some of the ocean's tiniest swimming animals can have a huge impact on large-scale ocean mixing."

Nature's smartdust

Communication, decision making, 'city living', accelerated mutation, navigation, learning and memory.

-- Six reasons 'why microbes are smarter than you thought.'

Remarkable though these behaviours are, we have probably only scratched the surface of what single-celled organisms can do. With so many still entirely unknown to science, there must be plenty more surprises in store.

Stentor