Friday, January 6, 2017

Bacteria, Molecules, and Other Small Things That Sense and Remember



Here I’ve compiled some articles from my notebook that look at how our senses work when it comes to simpler forms of life, like bacteria. There’s even something about how molecules – very far from what we consider ‘living things’ – uses a form of memory. All this has been put together to reinforce an idea presented in Hidden Scents which suggests that our awe-inspiring brain is similar to things less inspiring, like the lowly eukaryote.

Some of these things are really old, and most of the text here is copied from the links provided. Overall I hope it’s interesting enough to keep your attention:

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“…there is a distinction between an organism reacting to a chemical that it encounters directly (in analogy to the sense of taste) and a reaction to a chemical that is floating around in the air, says Reindert Nijland, lead author of the study.

"The compounds detected by olfactory organs are generally much more volatile than things you can taste like 'sweet' or 'salt', and therefore can provide information about things that can be much further away; you can smell a barbecue from a few blocks away whereas you have to physically touch and eat the steak to be able to actually taste it."

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phys.org, Feb 2016

“ "Very little is known about the microbes of the built environment," microbiologist Maria Gloria Dominguez-Bello of New York University, who led the pilot study, said at a meeting of the American Association for the Advancement of Science.


“Her team found that as people living in the Amazon rainforest become more urbanized, the kinds of bacteria in their homes change from the bugs mostly found in nature to those that typically live on people, she reported Friday.

In fact, in city dwellings, the researchers could tell just by the microbial fingerprints of the walls that "this is a kitchen or this is a bathroom or this is a living room. That's amazing," Dominguez-Bello said.

“Despite fewer occupants, the more urbanized a dwelling, the more human bacteria lived on its walls and floors, the researchers reported in the journal Science Advances. In Manaus, a collection of microbes normally found in the mouth, including various species of strep bacteria, and in the gut were the most important in telling rooms apart. The more crowded jungle and rural homes nonetheless were filled with more bacteria commonly found in soil and water than with human microbes.”

The microbiome has become a big deal lately. As much as it is invisible, it’s not unrecognizable.

Its kind of funny how, first, we didn’t know what microorganisms were one hundred years ago, and are only now beginning to understand the role of microbes (in their totality, as the microbiome) in human health, and yet, I would conjecture that the smell of the microbiome, its dynamic states of existence and effects, have been well known to us for quite some time. I cannot see your body odor, even if I look really close. But I know it’s there.

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phys.org, Feb 2016

This isn’t about smelling, but sensing nonetheless…

“Dmitri A. Nusinow, Ph.D., assistant member at the Danforth Plant Science Center and researchers in his lab studying plants' circadian clock have discovered a gene that allows plants to remember daylight during the long nights of winter, helping them tailor their growth appropriately to the seasons.”

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BBC, Feb 2016

“After more than three centuries of scientists eyeballing bugs under microscopes, Prof Mullineaux said it was remarkable that nobody had picked up on this before.”

“the entire organism acts like an eyeball”

“Cyanobacteria, including the Synechocystis species used in the study, are an ancient and abundant lifeform. They live in water and get their energy from photosynthesis - which explains their enthusiasm for bright light.”

Can’t resist mentioning that cyanobacteria are what make the ‘smell of the seashore;’ it emanates from their little bacteria bodies as they metabolize, and we can also call it seaweed sweat or seaweed pheromones or seaweed seeking sex.

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phys.org, Jan 2016

“This device, reported in the Jan. 28 issue of the journal Nature, is the first fully integrated electronic system that can provide continuous, non-invasive monitoring of multiple biochemicals in sweat.

“The advance opens doors to wearable devices that alert users to health problems such as fatigue, dehydration and dangerously high body temperatures.

"Human sweat contains physiologically rich information, thus making it an attractive body fluid for non-invasive wearable sensors."

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[and on that note...]
phys.org, Feb 2016

"Thousands of bacteria species have the potential to live on human skin, and in particular in the armpit," says Rob Dunn, a professor of applied ecology at NC State and co-author of the paper. "Just which of these species live in any particular armpit has been hard to predict until now, but we've discovered that one of the biggest determinants of the bacteria in your armpits is your use of deodorant and/or antiperspirant."


"We found that, on the first day, people using antiperspirant had fewer microbes in their samples than people who didn't use product at all - but there was a lot of variability, making it hard to draw firm conclusions," Horvath says. "In addition, people who used deodorant actually often had more microbes - on average - than those who didn't use product."

“By the third day, participants who had used antiperspirant were beginning to see more microbial growth. And by day six, the amount of bacteria for all study participants was fairly comparable.

"However, once all participants began using antiperspirant on days seven and eight, we found very few microbes on any of the participants, verifying that these products dramatically reduce microbial growth," Horvath notes.

“The participants who had been regular antiperspirant users coming into the study had wildly different results. Sixty percent of their microbes were Staphylococcaceae, only 14 percent were Corynebacteria, and more than 20 percent were filed under "other" - meaning they were a grab-bag of opportunistic bacteria.

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[aaaandddd]
phys.org, Nov 2015

“Swarm robotics is an emerging approach to the coordination of multi-robot systems, which takes inspiration from the natural world to examine the possibilities for improved interaction between robots and their surrounding environment.

“Until now, researchers specialising in swarm robotic applications have been unable to replicate all the aspects of pheromone communication that occur in the natural world.


“Specialists from the University of Lincoln's School of Computer Science have now produced a novel artificial pheromone system that is reliable, accurate and only uses 'off-the-shelf' components …[which] allows users to simulate several pheromones and to change their strength.


“Led by Farshad Arvin, PhD researcher in the School of Computer Science, the Lincoln team developed the system using their own Colias platform. They created Colias - an open-platform system that can be used to investigate collective behaviours and be applied to swarm applications - in 2014 in collaboration with experts from Tsinghua University in China.”

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