澳门六合彩历史记录

New 澳门六合彩历史记录 research shows that bacteria harness physical laws to operate at the edge of chaos and use calcium to independently diversify and find a place to settle down

Let鈥檚 talk about the bacteria in our colons.

Like all life on this planet, their main goal is to replicate their genome, passing it on to the next generation. But hostile environments like the colon force them to make tough choices: Hunker down here or swim farther downstream in hopes of greener pastures?

Meanwhile, all their kin are making the same calculation. Each has the same genome but can鈥檛 follow the same instruction manual or else they鈥檒l all land on the same spot. They must diversify. So, how does a single-cell organism lacking the benefit of billions of neurons know how to do that?

finds that bacteria鈥攁nd not just the kinds in our colons, but many types in many environments鈥攗se changes in calcium, controlled through a process called 鈥渟elf-organized criticality,鈥� to spontaneously diversify without the need for communication between cells. Bacteria use calcium not only in governing the transition to a biofilm, but in movement, maintaining cell structure and in infection.

Understanding how calcium is regulated in bacteria may have significant future implications for, among other applications, treating harmful biofilms that can form on surfaces. Further research may help scientists interrupt a bacterium鈥檚 calcium dynamics, perhaps preventing it from settling on a surface in the first place.

鈥淏acteria have so much to teach us,鈥� says Christian Meyer, a postdoctoral fellow in the 澳门六合彩历史记录 Department of Molecular, Cellular and Developmental Biology who completed the research with former 澳门六合彩历史记录 assistant professor Joel Kralj. 鈥淭here鈥檚 a fallacy in assuming that because something is small, it鈥檚 simple. Bacteria are using statistical mechanics to run computations instantaneously that I run over an entire weekend on my computer.鈥�

Not more evolved than bacteria

In fact, Meyer鈥檚 research was inspired, in part, by the prevalent notion that humans are the pinnacle of evolution and the idea that 鈥渨e鈥檙e more evolved than ________鈥濃�攖han amoebas, than earthworms, than bacteria.

鈥淭hat鈥檚 not at all what evolutionary theory is saying,鈥� Meyer notes. 鈥淭he theory is that you, as a human, would make a horrible worm. Each unto their own niche. There are lots of systems in the natural world that operate without 鈥榠ntelligence,鈥� by which I mean that bacteria aren鈥檛 sitting there with a billion neurons at their disposal to figure out how much calcium they should let in right now. They have to do that rapidly and in changing environments, but also energy efficiently, and do it instantaneously鈥攖hey鈥檙e not thinking.鈥�

Originally, Meyer and his research colleagues studied antibiotics and how they modify the electrophysiology鈥攐r the electrical properties of cells that include current and voltage鈥攐f bacteria. that E. coli bacteria, when treated with certain antibiotics, respond with changes in membrane potential.

In hundreds of videos of antibiotic-treated bacteria, the scientists watched calcium, as a marker of cell membrane voltage, going in and out of the cell. Instead of general randomness in that process, they saw power laws at work. Power laws describe the probability of an event happening as a function of its magnitude or duration. For example, the relationship between the probability and magnitude of an earthquake follows a power law, with large earthquakes being less likely than small ones.

Through further research with strains of E. coli, B. subtilis and P. putida bacteria, they found that calcium fluctuations resulted from a property known as self-organized criticality (SOC). SOC is a general property of many natural systems that are poised at the boundary between two phases without external control. Rather than separate states of matter, the phases are defined as different dynamical regimes, and often SOC systems are poised at the boundary between ordered and chaotic dynamics鈥攚hat has been described as 鈥渙rder at the edge of chaos.鈥�

Using self-organized criticality

Meyer and Kralj found that SOC can explain how bacteria cells exist on a knife鈥檚 edge between very high levels of calcium outside the cell and calcium levels that are about 100,000 times lower inside the cell.听 At high levels, calcium can be cytotoxic, meaning it can damage or kill cells. So, the bacteria鈥榮 membranes operates somewhat like a dam, opening and closing rapidly and often鈥攂ut not in a consistent pattern鈥攖o pump calcium in and out.

The research findings also suggest an evolutionary advantage of SOC, because it provides a way for individual bacteria to diversify, even without communicating with one another. SOC could be compared to a random number generator inside each bacteria cell, one that鈥檚 power law-based 鈥渟o big events are more likely than they would be otherwise,鈥� Meyer says.

鈥淏ecause of this, going back to the example of bacteria in the colon, a bacterium will swim farther down the colon than it would if it was just randomly swimming. This is an extremely efficiently search strategy, to use power law-based searches in a domain. From my perspective, I think how incredible it is that they鈥檙e using a physical process to run computations to figure out what they should be doing, all without talking to each other or 鈥榯hinking鈥�.鈥�

While understanding how calcium dynamics in bacteria result from SOC is an important step, further research will need to study how to target calcium while leaving a bacterium鈥檚 membrane electrical voltage intact. Then researchers can begin working toward applications like treating harmful biofilms.

鈥淚鈥檝e really grown to admire what bacteria are capable of doing,鈥� Meyer says. 鈥淚magine being a one-femtoliter cell (one-quadrillionth of a liter) and having to survive in the crazy world we live in with all the changes in temperature and pH and nutrients. It鈥檚 a hard world, but they鈥檝e come up with incredibly elegant solutions to the complex challenges they face.

鈥淚n some ways, I鈥檝e been inspired thinking how can we co-opt some of these natural processes for solving some of the issues humans face and do it in an intelligent way, things bacteria figured out a long time ago. SOC systems are an interesting mixture of flexible yet robust without the need for constant tuning. These seem desirable properties for many anthropogenic systems, from AI to social networks.听I鈥檝e come to appreciate bacteria as good examples of combating that fallacy of we are the pinnacle of evolution. They have amazing secrets to teach us, we just have to look at them.鈥�

Top image: AI-generated picture of bacteria

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