Posts Tagged ‘microbes’
“Bacteria represent the world’s greatest success story”*…
But as Stephen Jay Gould goes on to observe (in his 1996 book, Full House: The Spread of Excellence from Plato to Darwin), “They are today and have always been the modal organisms on earth; they cannot be nuked to oblivion and will outlive us all. This time is their time, not the ‘age of mammals’ as our textbooks chauvinistically proclaim. But their price for such success is permanent relegation to a microworld, and they cannot know the joy and pain of consciousness. We live in a universe of trade-offs; complexity and persistence do not work well as partners.”
Still, we (more complex) humans have recognized– and accommodated– bacteria for millennia. As We Make Money Not Art explains in a review of a recent book– We The Bacteria. Notes Toward Biotic Architecture by architectural historians Beatriz Colomina and Mark Wigley— that’s fascinatingly apparent in the history of architecture…
This “alternative history of architecture from the point of view of microbes” compiles the research that led to the exhibition We the Bacteria: Notes Toward Biotic Architecture at the 24th Milan Triennale last year. Curated by Colomina and Wigley, the show investigated how microbial ecosystems relate to spatial design and health inequality.
The book argues that microbes have not only built the whole planetary biosphere but they have also been the real architects of our homes and cities throughout the ages. Or rather, it’s the fear and diseases they cause that have shaped our spaces and the ways we move through them.
About ten thousand years ago, humans began retreating into spaces increasingly cut off from the exterior world. Plants, soil and insects could be left outside. But microbes, including pathogenic ones, followed humans inside their homes, where they adapted, mutated and generated new diseases. As our shelters expanded into villages, cities and sprawling empires, so too did the microbial ecosystems.
The authors narrate how buildings and bodies exist in a constant microbial exchange, co-evolving into a single, dynamic ecosystem. The microbiome of a home is highly specific to its inhabitants. Even the microbiome of a frequently cleaned hospital room resembles the microbiome of the previous patient, but starts to resemble that of a new occupant after twenty-four hours.
Architecture cannot exist without microbes, and, by extension, without disease. While scrubbing, spraying and disinfecting may eliminate most microorganisms, these practices also breed extremophiles, species so resistant that they can take over the space.
Throughout history, the book reveals, health crises have dictated architectural and urban design. From toilets to fumigation systems, from the plague hospitals, aka lazarettos, to the sanatoriums for tuberculosis patients; from sewage systems to urban parks, cities have been continually reshaped in response to the threats they sought to contain. Architecture became the first line of defence against microbes…
[More of the intertwined history of bacteria and our reponse to them, with lots of fascinating photos…]
… Given the important role that microbes play for our immune systems and the environments we inhabit, the authors call for a biotic architecture. Biotic architecture is less human-centric than traditional architecture. It learns from microbes rather than resists them. It does, of course, maintain some antimicrobial protocols against pathogens remain crucial. Water, sewage systems, toilets and food preparation areas still need to be cleansed, but cleaning routines should also embrace controlled exposure to microbial diversity. During COVID-19, for example, microbiologist Elisabetta Caselli and her colleagues replaced conventional disinfectants with probiotic-based sanitation in six Italian public hospitals. The result was a decrease in surface pathogens by up to 90% compared to conventional chemical cleaning and lower rates of healthcare-associated infections and antibiotic resistances… For once, here is a book that presents a vision where humans can actively contribute to microbial diversity, collaborate with the unseen world around us and build in ways that nurture rather than harm the environment…
More– and more fascinating images– at: “We The Bacteria. Notes Toward Biotic Architecture.”
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As we coexist, we might recall that it was on this date in 2012 that Rebekah Speight of Dakota City, Nebraska sold a McDonald’s Chicken McNugget that resembled President George Washington for $8,100 on eBay (the third most expensive McNugget ever sold). She had kept the McNugget in her freezer for 3 years before deciding to sell it…. because bacteria.
“The vast majority of terrestrial species are in fact microbes, and scientists have only begun scratching the surface of the microbial realm. It is entirely possible that examples of life as we don’t know it have so far been overlooked.”*…
Not only do we continue to find surprising new forms of microbial life, some of them challenge our very defintion of “life.” Alice Sun reports…
Scientists recently discovered a microbe with one of the tiniest genomes on Earth. More surprising, the creature is almost entirely dependent on its host: Its genes don’t support any of the functions of metabolism, one of the key processes of life. As such, it challenges fundamental notions of what it means to be a living organism. The discovery was “pure serendipity,” says Takuro Nakayama, an evolutionary microbiologist at the University of Tsukuba in Japan. Takayama wanted to study the many microbes that live within a single-celled marine dinoflagellate, Citharistes regius, a kind of plankton. But when he and his colleagues sequenced the genes of this microbial community, they kept turning up tiny, odd chunks of DNA.
It turns out that these DNA chunks belong to some unusual archaea—a branch on the tree of life populated by single-celled microbes that can often survive in extreme environments. (Archaea are similar to bacteria, but distinct in their structure, genetics, and metabolism.)
Nakayama and his colleagues proposed the name Sukunaarchaeum mirabile for the newly-discovered microbe: Sukunaarchaeum after the Japanese dwarf deity Sukuna-biko-na, and mirabile for marvelous. At only 238,000 base pairs, the number of genes in the DNA of Sukunaarchaeum is smaller than that of any other known archaea. The scientists described their finding in a bioRxiv preprint earlier this year.
So how did Sukunaarchaeum end up with such a strikingly tiny genome? Over the course of evolution, genetic instructions for life often become increasingly complex. But evolution can also go in the other direction, leading to greater simplicity in the genome. This so-called genomic reduction, where organisms end up with fewer genes than their ancestors, is typically observed in the domains of bacteria and archaea. What struck Nakayama and his colleagues about Sukunaarchaeum was the extent of reduction and specialization in its genes.
With its stripped down genome, Sukunaarchaeum appears to be completely dependent on its host, C. regius, for essential energy and nutrients. “It likely cannot produce its own cellular building blocks,” notes Nakayama. “No previously discovered microbe has shown such an extreme degree of metabolic dependence.”
Sukunaarchaeum seems to almost inhabit a new category of life, suspended somewhere between archaea and virus. It is like viruses—which aren’t typically considered to be “alive”—in that it has a tiny genome and is totally dependent on its host for metabolism. But unlike a virus, Sukunaarchaeum has its own ribosomes, cellular structures that synthesize proteins, and it can replicate itself without the help of a host.
To get a sense of just how unusual Sukunaarchaeum is, the researchers decided to scan the oceans for potential relatives. They analyzed environmental genetic sequence data from marine environments all over the world, focusing on spots where C. regius is known to live. Using a database called the Tara Oceans project, they discovered a vast array of sequences that are comparable to that of Sukunaarchaeum, which they hypothesize could represent a new, deeply branching archaeal lineage.
For Nakayama, this additional finding suggests that many more microbes that challenge the definition of life may be out there, living in what Nakayama calls “microbial dark matter,” or microbes that can’t be cultivated in the lab. “The extreme, virus-like lifestyle we hypothesize for Sukunaarchaeum is a perfect example of the surprising outcomes found in this ‘natural laboratory of evolution,’” he says.
Mart Krupovic, a virologist and microbiologist at Institut Pasteur in France who wasn’t involved in the study, called the finding “remarkable.” Krupovic has studied giant viruses that, like Sukunaarchaeum, defy categorization. These giant viruses have evolved larger and more complex genomes that include some of the genes for DNA translation, a characteristic thought to be reserved for cellular life. “I think that is fascinating,” says Krupovic, “how little we still know about the world which surrounds us.”…
How did Sukunaarchaeum end up with such a strikingly tiny genome? “A Rogue New Life Form,” from @alicesunreports.bsky.social in @nautil.us.
See also; “Candidatus Sukunaarchaeum Mirabile Is A Novel Archaeon With An Unprecedentedly Small Genome” (source of the image at the top).
The BioRxiv preprint is here.
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As we look again at “living,” we might spare a thought for Robert Huebner; he died on this date in 1998. A physician and virologist, his research into viruses, their causes, and treatment led to his breakthrough insights into the connections between viruses and cancer, which have led to new treatments. His hypothesized oncogene was discovered to be a trigger for normal cells turning cancerous.
“In the end everything is connected”*…
A fungus known as a Dermocybe forms part of the underground wood wide web that stitches together California’s forests [source]
Research has shown that beneath every forest and wood there is a complex underground web of roots, fungi and bacteria helping to connect trees and plants to one another.
This subterranean social network, nearly 500 million years old, has become known as the “wood wide web.”
Now, an international study has produced the first global map of the “mycorrhizal fungi networks” dominating this secretive world…
Mycorrhizal ecologist Dr Merlin Sheldrake, said, “Plants’ relationships with mycorrhizal fungi underpin much of life on land. This study … provides key information about who lives where, and why. This dataset will help researchers scale up from the very small to the very large.”…
The underground network of microbes that connects trees—charted for first time: “Wood Wide Web: trees’ social networks are mapped.”
Read the Nature release that reports the research here.
* The Book of Chameleons
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As we contemplate connection, we might spare a thought for Anders (Andreas) Dahl; he died on this date in 1789. A botanist and student of Carl Linnaeus, he is the inspiration for, the namesake of, the dahlia flower.
Dahlia, the flower named after Anders Dahl [source]
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