Discover algae fraud

- They hunt, eat, cheat: unicellular algae shed light on the social life of microorganisms.

Fraud is an act that not only happens in humans, animals and plants. A group of Arizona University researchers have discovered that even single-celled algae that are only observed under a microscope do so.

Humans can cheat, chimpanzees and cuckoo alike - cheating for a free ride is a behavior that has been documented in many animals, even plants. But what about single-cell algae cells? Yes, they also have that behavior, biologists along with the University of Arizona ecology and evolutionary biology have discovered this.

"There are fraudsters we don't know about yet," said William Driscoll, lead author of a research report, who studied a toxic algae that destroys the environment. The study is part of his doctoral studies in the laboratory of Jeremiah Hackett, an assistant professor of ecology and evolutionary biology.

Driscoll isolated a number of strains of Prymnesium parvum, and found that some grow faster and do not produce any toxins that protect algae against competition with other algae.

"When those" fraudsters "are cultivated with copies of their toxins, they can still benefit from the toxins produced by their collaborating" neighbors "- they're real. the freedom of passengers, " Driscoll explained.

Research published in Evolution magazine adds, emerging views that bacteria often have positive social life. Future research into the social aspect of toxic algae can open up a new approach to controlling or counteracting toxic algae blooms. This phenomenon can pose a serious threat to human health and can wipe out local aquatic species.

Prymnesium belongs to a group of algae known as yellow algae, named for their pigments, due to these pigments, the algae are yellowish.

This poisonous algae mainly lives in the sea and only invades freshwater environments recently. Its distant relatives include diatoms, algae that make up a large part of the plant's plankton and giant kelp.

Algae can produce toxins that kill fish, but so far it has not shown a threat to human health or livestock. Many scientists believe that toxins arise as a chemical weapon to wipe out other algae and other organisms that compete for nutrients and sunlight that depend on algae. The discovery of those who 'cheat' does not bother with the production of toxins which is a phenomenon that must be noticed by scientists.

"We are trying to understand the ecological aspect of these algae," Driscoll said.

"If you are a single cell, whether you create a toxin or not, you are just passing water, and everything is floating with you , " Driscoll said. "Producing toxins is only meaningful if all the cells do the same. Any single cell will not get any benefit from the chemicals it makes because of the chemical. This substance will immediately diffuse. This is a bit similar to the disciplinary behavior of fish: a lone fish cannot distract a carnivore, need a fish to do it together. " . For that reason, he explained, fraudsters must have an advantage right on their 'honest' neighbors, because they can invest energy and resources that they save on their jobs. create more children.

"The theory tells us that cooperation will be broken in these cases. If you are secrete a poison and it benefits your species, then everyone gets that benefit. In a well-mixed crowd, without a group structure, natural selection will support selfishness, and cheaters will succeed. '

But for some reason, they didn't do that. An alternative explanation for toxicity becomes apparent when toxin-containing cells are observed in their competition under a microscope.

"They attack other cells," Driscoll said. " Using their whips, they swim up to their prey and cling to it. Sometimes a fight takes place, and more cells will swim to, surround their victims and release more toxins. more, and then they eat that cell ".

"These toxins may have evolved less significantly to keep distance from competitors and more like a rattlesnake venom. Algae can use toxins to stun or numb. whether prey, " Driscoll and his colleagues isolated isolated and non-toxic strains from the same water sample taken from a late blooming algae when the flowering phenomenon began to decline.

"When opportunities are good and there are plenty of nutrients in the water, algae use photosynthesis to get energy from sunlight, but when nutrients become less, they attack and become available. poison, " Driscoll said. "That's when they start swimming around looking for prey. That way they're a bit like carnivorous plants - just like a fly catcher."

The team observed that as soon as the nutrients became scarce, the toxic cells stopped growing, but the fraudsters continued to multiply.

Driscoll and his research team think that cheating can be an adaptation to algal blooms.

"During the flowering period you have killed all or a large number of prey, so why produce toxins and look for something that is not there? Perhaps it is better to continue to grow and don't even bother to continue searching for prey because they have disappeared. '

Driscoll said the study showed that scientists also knew very little about microbial ecology.

"We are just beginning to understand the mechanisms that maintain cooperation in microbes. The majority theory is tilted towards multicellular organisms. Only recently have scientists begun to care. to collaboration in microbes'.

To better understand the genes and biochemical pathways that control how algae produce their toxins, the team in Hackett's lab is working to find out which genes work in these strains. Toxic bacteria compared to non-toxic strains.

"We are looking for some stress-related genes that are arranged differently in cheating cells , " Driscoll said. "Many other genes have not been studied, especially those that are more likely to be involved in the production of toxins."

"The problem is that nothing is close to these algae that have been sequenced, so they are quite mysterious to scientists. Many of the genes we have arranged are new. strange, so understanding their function is a big part of this challenge. '

Clarifying the molecular mechanism behind all chemical wars, fraud and maximum growth is likely to lead to new applications, researchers speculate, albeit cautiously.

Driscoll explained that cheating traits could be an Achilles heel, which could be exploited to limit algal blooms.

"We are interested in influencing the competitiveness of populations that form this flowering phenomenon. While this study is just a brief summary, understanding how natural selection can work. Dynamic flowering through the flowering process can provide a deeper understanding of the most important characteristics for the success of this species. "

In addition, the trend of fraud continues to increase as their toxic neighbors are no longer growing. This is reminiscent of cancer cells.

According to Driscoll, one way to think about cancer is that cancer cells have an immediate advantage over non-cancerous cells next to them, good behavioral neighbors.

However, this advantage, if not controlled, is very short-sighted because it will affect the basic functions of multicellular organisms.

"What we can see in algae is a version of a similar story, because a short-term advantage to not produce toxins can affect people's long-term competitiveness. Fewer extremists ".