Amazing bacteria, unexpected

  Scientists have cultivated all kinds of beneficial bacteria in the laboratory, which can help us clean up pollution, recycle waste, regenerate energy and maintain good health.
  We are facing a crisis: mankind’s excessive dependence on fossil fuels and the preference for foods with high carbon footprint are continuing to cause environmental degradation and global warming. The land and sea are polluted by a large number of disposable plastics, and pathogenic bacteria that have been immune to antibiotics It is also threatening public health.
  The good news is that: carbon dioxide can be separated from the atmosphere to delay global warming; high-quality protein can be produced without discharging a large amount of carbon; pollution problems and bacterial resistance are also countermeasures. These potential breakthroughs are all based on a common element-bacteria. Although it sounds unreliable, our future health and happiness may be guaranteed by these humble microorganisms.
  Can cure bacterial disease
  bacteria can harm health, cause tuberculosis and cholera and other deadly diseases. In order to combat pathogenic bacteria, one of the greatest human inventions in the 20th century, penicillin, was widely used, saving about 200 million lives in the past 80 years. But in addition to being harmful, bacteria can also be human “friends.” Scientists have discovered that bacteria exist in large numbers on the surface of human skin and in the intestines, and the number is in the billions. Good bacteria not only convert food into energy, but also resist the invasion of bad bacteria that can cause disease, because when the good bacteria completely occupy the intestine, the bad bacteria will naturally have no “foothold”. But sometimes human intervention can break this balance. Long-term use of antibiotics will cause some of the good bacteria in the intestine to be killed, and the bad bacteria such as Clostridium difficile (“Clostridium difficile”) and other pathogenic bacteria take advantage of the deficiency. Infection with C. difficile can cause diarrhea, nausea and fever.
  However, the research of the past few decades has provided a new idea for the treatment of C. difficile infection-stool transplantation, that is, transplanting stool samples of healthy volunteers into the intestines of patients, using good bacteria in the samples to defeat C. difficile, thereby Restore the balance of the patient’s intestinal flora. In addition, stool transplantation has the potential to treat other diseases. Scientists have studied the interaction between animals and microorganisms, but it is still unclear which type or which bacteria in the stool sample are good for human health.
  On the other hand, scientists have mastered the mechanism of action of certain types of bacteria (such as Escherichia coli), so they can be used accurately to treat diseases. E. coli is very common in the human body and is almost harmless. Based on the research of the past decades, scientists have fully understood the characteristics of E. coli and compared it to a “programmable micro-biological computer” that can cure diseases. This is because some probiotic strains of E. coli can find malignant tumors. And grow in it. This makes them the best choice for targeted delivery of tumor therapy drugs.
  Based on the mechanism of Escherichia coli “searching” for tumors, scientists insert a piece of foreign DNA into their cells to make them produce powerful anti-cancer molecules “nanobodies”. When this E. coli finds the tumor cells and multiplies in them, another piece of foreign DNA inserted makes the E. coli “self-detonate”, thereby releasing the “nanobody” to the surrounding tumor tissue. In other words, once the processed E. coli enters the body of the tumor patient, they will automatically seek the target and eliminate the tumor. Scientists have conducted experiments in this area on mice in early 2020 and have achieved gratifying results. However, due to ethical and safety considerations, there are still some obstacles before the start of human trials of genetically modified microorganisms, and a series of regulatory procedures may need to be initiated.
  Bacteria can produce renewable energy
  bacteria are distinguished chemist, they are not only capable of producing a powerful anti-cancer drugs, can produce large amounts of renewable fuels. In early 2020, a study by the British scientist Scruton’s team demonstrated the potential of bacteria to generate electricity. Many bacteria contain a fibroblast activation protein (“FAP” for short, which is a catalytic enzyme), and they have modified FAP. The modified FAP can decompose human food residues through fermentation and produce propane gas. Propane gas is generally used as fuel for transportation, domestic heating and cooking.
  The above-mentioned research already has certain commercial value, but scientists have inserted modified FAP into Halomonas to make them generate electricity, which is expected to be applied to industry on a large scale. Halomonas is one of the few bacteria that can survive in higher concentrations of salt water. At present, most industrial fermentation equipment is made of steel, and strict sterilization must be carried out before use to ensure that there are no bad bacteria in the fermentation tank, so as not to reduce the fermentation efficiency. And the fermentation of Halomonas has a significant advantage: that is, except for themselves, other bacteria, good or bad, can hardly survive in salt water. The use of Halomonas can reduce the cumbersome degree of sterilization steps and the resulting high amount. cost. In addition, the fermentation process of Halomonas can even be carried out in a cheap reactor (such as a plastic container), so the cost of the fermenter is also greatly reduced.
  At present, in addition to Halomonas, there are several other methods of using bacteria to produce bioenergy. One is to use the behavior of “electrically active” bacteria to “swallow” and “exhaust” electrons to generate electricity. Place an electrode on the ground, and if the environment is right, “electrically active” bacteria will start to grow around the electrode. Scientists have spent several years studying how to use these “electrically active” bacteria to produce renewable energy. In an experiment in 2010, scientists “starved” Myriadalis by stopping providing food (hydrogen) to them, and instead provided them with sufficient electrons. They adapted the mouse spore bacteria to feed on electrons and used their own electricity to convert carbon dioxide into acetate. Scientists call this process “microbial electrosynthesis”. The resulting acetate is a chemical substance with commercial value, which can then be made into plastic or biofuel. Moreover, the efficiency of “microbial electrosynthesis” to produce biofuels may surpass agriculture, because solar energy can power bacteria. And this method of directly using solar panels to capture solar energy to power bacteria is much faster than the method that plants convert solar energy into organic matter to power bacteria through photosynthesis (for example, using rapeseed to produce biofuels).
  At the beginning of 2020, scientists also explored another method of producing renewable energy. The key to this method is a conductive flagella that grows on the surface of electroactive bacteria. The flagella are scraped off the surface of the bacteria, and they are sandwiched between two gold guide plates, and the difference in humidity is used to obtain electricity directly from the air. This simple device just started generating electricity. After calculation, scientists speculate that if the size of the “air power generation device” is large enough, its power generation efficiency can even exceed that of solar panels. Moreover, the electromagnetic panel relies on light, and the “air generator” can output electric energy stably even at night.
  You can purify water of bacteria
  Bacteria are the ultimate recyclers of waste. Sewage sewage is waste water for humans, but it is a good meal for some bacteria. This is why bacteria play an important role in the sewage treatment process. The main “employee” of the sewage treatment plant is aerobic bacteria, which means that air pumps must be used to continuously pump air into the sewage to provide enough oxygen for the aerobic bacteria to continuously decompose the waste in the sewage. To keep the air pump running, the cost is quite high.
  In fact, the operating costs of sewage treatment plants can be reduced. Scientists have developed a new method to purify industrial wastewater, while generating electricity, and the generated electricity is more than the electricity consumed. In theory, this is completely feasible. On the one hand, industrial wastewater is usually rich in “nutrients” (for example, wastewater from dairy factories is usually rich in carbohydrates and proteins), which are themselves an energy substance, and bacteria that do not consume oxygen are used to decompose waste in the water. The operating cost of the air pump can be saved. “Electrically active” bacteria (such as Geobacter and Shewanella) feed on wastes in the water (decompose wastes) while expelling electrons or other charged substances (generating electricity). On the other hand, the charged material produced can also be used as food for a kind of “methanogenic bacteria” for them to convert carbon dioxide into methane, which in turn can provide energy for heating and power generation.

  In fact, the idea of ​​using microorganisms to treat wastewater and generate electricity at the same time was formed as early as ten or twenty years ago, but there are very few energy substances in urban sewage, so it is not easy to successfully convert laboratory solutions into commercial systems. If sufficient power generation is to be generated, the amount of waste water that needs to be treated will be huge. It is much more reasonable to use microorganisms to treat industrial wastewater, because industrial wastewater contains more energy materials than urban sewage.
  The bacteria can make proteins
  the bacteria can “feed” the world. When some bacteria convert carbon dioxide into fuel, other bacteria (such as hydrogenotrophic bacteria) decompose carbon dioxide and combine with other substances to produce protein for human consumption.
  We don’t need to be surprised by this. In fact, plants that can be eaten by animals use photosynthesis to convert carbon dioxide into carbohydrates. Strictly speaking, plants have not actually evolved the ability to convert carbon dioxide into food, but instead rely on the absorption of photosynthetic bacteria into their cells to obtain this ability.
  As far as the ability to capture solar energy is concerned, organisms that use photosynthesis are far inferior to solar panels. In this regard, scientists have an idea: Can bacteria use solar energy and carbon dioxide to synthesize protein? If feasible, then we will harvest food at an unprecedented super speed.
  To realize this idea, it involves solar energy splitting water molecules and using the generated hydrogen to provide nourishment for bacteria in the fermenter. Then, use these bacteria to combine the carbon dioxide in the air to synthesize high-quality protein, thereby replacing animal protein in the daily diet. This method also has the advantage that the fermenter used has a small footprint, and only one brewery is needed to accommodate the entire production chain. Therefore, some farms can be reduced to forests to absorb more carbon dioxide in the air. In this way, the earth can even achieve “negative carbon emissions”, that is, it absorbs more carbon dioxide than it emits.
  Scientists believe that the use of bacteria or other microorganisms in the future can produce more proteins that are environmentally friendly to the earth. Adding them to oatmeal, milk, bread or other pasta can increase the protein content of the diet. But the specific food to be added depends on the consumer’s acceptance of “bacterial protein”.
  Smothering gas can be eaten warm bacterium
  bacteria is small, but they have great potential to control climate change, because there are a variety of bacteria will “eat” the main greenhouse gas carbon dioxide, the earth, but they “eat” too slowly .
  Fast-growing bacteria can break down carbon dioxide faster, but they tend to feed on sugars more than carbon dioxide. In 2019, Israeli scientist Milo inserted the DNA of photosynthetic bacteria that feed on carbon dioxide into the cells of Escherichia coli (a fast-growing bacteria), and then placed them in a high-concentration carbon dioxide environment with almost no sugar. Milo speculated that as long as there is enough time, these modified bacteria may undergo huge changes in metabolism. Sure enough, a year later, these E. coli actually feed on carbon dioxide. If this Escherichia coli can be applied in practice, this will be a major breakthrough and will have a positive effect on delaying global warming.
  In addition, other scientists are also conducting experiments, hoping to increase soil carbon capacity by injecting “carefully modified” microorganisms into the soil, while promoting crop growth. They claim that this method can absorb 10 tons of carbon dioxide per hectare of land. In other words, in just one year, the agricultural land on the earth can absorb all the carbon dioxide emitted by humans. However, ecologists believe that we do not yet understand the properties of microbial communities in the soil, so there are still many difficulties in “carefully modifying” these microorganisms. If the modification of microorganisms can improve the soil carbon capacity, instead of injecting foreign microorganisms into the soil, it is better to provide the existing microorganisms in the soil with the necessary nutrients to make them play a greater role.
  Bacterial contamination can be purified
  in almost all carbonaceous substances on the earth bacteria break. Some bacteria have even evolved the ability to decompose marine oil slicks or similar pollutants. The oil spill in the Gulf of Mexico in 2010 caused at least 2500 square kilometers of seawater to be covered by oil, and a large number of oleophilic bacteria were produced under the oil slick.
  The ability of bacteria to decompose oil has attracted the attention of scientists. They are analyzing bacterial colonies in oil-contaminated soil, hoping to find the bacteria with the strongest decomposing power. However, there is a problem with the use of bacteria to decompose petroleum pollutants in the soil, that is, we still know very little about the characteristics of the microbial community in the soil. When foreign microorganisms are introduced into the soil, they are likely to compete with the microorganisms originally present in the soil, and the results of the competition cannot be predicted.
  Currently, bacterial purification is still an important part of the pollution purification process. More importantly, microorganisms have amazing evolutionary capabilities and the ability to adapt to feed on new substances. If the soil near the factory is contaminated with oil, the microorganisms in these soils are likely to start feeding on the oil. Scientists can use “biological stimulation” to provide them with other nutrients needed to maintain “health” (such as nitrogen fertilizer, phosphate fertilizer and iron fertilizer) to help them break down oil more quickly.
  Scientists believe that it is possible to use genetic engineering to make bacteria convert heavy metals (such as mercury) into less toxic substances, but it also needs to consider whether the introduction of genetically modified organisms into nature will cause adverse consequences.
  Plastic can eat “feast” bacteria
  bacteria almost “not picky eaters” creatures, they are not only “eat” oil, they can “eat” a variety of other carbonaceous materials, such as plastics.
  In 2016, Japanese scientists collected samples of “polyethylene terephthalate” (PET), the plastic used to make polyester fibers in beverage bottles and clothing, from recycling stations. They found a plastic-eating bacteria in some PET samples. This bacteria uses substances such as PETase in its body to decompose plastics, and the resulting smaller molecules such as ethylene glycol can be used to produce new plastics. Scientists named this bacterium “Scolostella Osaka”. The amazing thing about this discovery is that the earth has been contaminated with PET plastic for no more than 80 years, so it took less than 80 years for the Sakai bacteria to evolve the ability to decompose PET plastic. This shows that the bacteria have a strong evolution. ability.
  However, Collapse Osaka decomposes plastic in the environment very slowly. Biologists separate the enzymes that help decompose plastics from their bodies, and improve the decomposition efficiency by changing the structure of the enzymes. In 2018, a British team modified the structure of Collapse Osaka PETase and successfully increased the efficiency of Collapse Osaka decomposing plastic by nearly 20%. Now, they are exploring the modification of other bacterial enzymes to find an efficient way to decompose plastics with commercial value. In a study in early 2020, after scientists isolated a bacterial enzyme, LCC, and twisted its structure, they discovered that the plastic decomposition process that originally took several days to complete can now be completed in just a few hours, and the decomposition efficiency is huge. improve. Later, they made new plastic bottles using materials obtained by decomposing plastic bottles (using petroleum as a raw material), and found that there was no difference in material between the plastic bottles before decomposition and the newly made plastic bottles. This experiment shows that through the decomposition of bacteria, this plastic can be recycled. Therefore, scientists believe that enzymes can be modified to help recycle plastics that cause serious environmental pollution.
  PET plastic is not the only plastic that can be broken down by bacteria. Earlier in 2020, scientists confirmed that polyurethane (commonly used to make insulating materials and car parts) can also be broken down by certain bacteria. What is exciting is that scientists all over the world are conducting a large number of related studies in this area, which shows that bacteria still have great potential in the decomposition of plastics.
  Bacteria that can decompose antibiotics
  In 1928, British biologist Alexander Fleming discovered the world’s first antibiotic-penicillin. To this day, humans are still using penicillin for antibacterial treatment, but excessive use of antibiotics will make pathogenic bacteria evolve Resistance. Unexpectedly, because some bacteria can break down antibiotics, they may help us solve the problem of resistance.
  Although some scientists have been studying these bacteria for more than ten years, they are still very surprised when they find that they really “eat” antibiotics. In 2018, scientists found an enzyme that helps bacteria break down penicillin in the soil and inserted this enzyme into E. coli. Although they think there is still a long way to go after this, they still hope that the transformed E. coli can eventually be used to decompose antibiotics in sewage. The biggest problem that may be encountered in this process is that the bacteria in contact with each other exchange DNA. Genes that break down antibiotics may be passed on to other bacteria, including harmful bacteria that may cause disease. After these harmful bacteria have genes to decompose antibiotics, the antibiotics originally used to kill them may be decomposed. In this way, we will be helpless against these bacteria. If you give scientists enough time to study the characteristics of bacteria in depth. They may be able to find a solution to these problems and make bacteria a weapon against antibiotic resistance.