The genetic version of POKEMON Go is in the human intestine.

The next puzzle of human disease decoding: talking about intestinal bacteria and obesity, opening a new vision of brain color reversing aging: is anti-aging protein GDF 1 1 a myth or a fairy tale? As long as it is anticoagulant, don't bleed! The key lies in the gene "I". who is it? Everyone's cells are composed of trillions of human cells and microbial cells. These foreign microbial cells began to "immigrate" from the moment people were born through the birth canal, and then attached or entered the human body with the processes of breathing, eating, touching, etc., and colonized in the skin, mucosa, respiratory tract, intestine and so on. These transplanted cells play various roles in the human body, profoundly affecting digestion, physique and immunity, and may even affect human emotions, thoughts and behaviors [Note 4-6]. At the beginning of 20 16, Dr. Alison Abbott said that the ratio of human bacteria to human cells proposed by Thomas Luigi in 10: 1 is a myth at present. According to the analysis of many scientific studies, the average ratio of human bacteria to human cells is between 1.3: 65438+. Even so, these foreign residents exert their influence and exert a subtle influence on our internal environment.

The average volume of colon is only about 0.6 liters, but it is the place with the largest number and species of bacteria in human body. At present, it is estimated that there are about 500- 1000 species of these intestinal bacteria, and the total number can reach more than ten trillion [note 7], which is very amazing. However, humans have never conducted a good household registration survey of these intestinal residents, so that the exact composition of intestinal bacteria, the functions of various bacteria and the interaction between bacteria are not very clear now, not to mention the effects and influences of these bacteria on human cells, digestive system, or personal thoughts and behaviors. In order to deeply understand the composition of human migratory bacteria, the United States invested1.65,438+0.5 billion dollars in 2008-2065,438+0.5 billion, and implemented the Human Microbiome Project (HMP), which is as important as the human genome sequencing project [Note 8].

HMP *** obtained more than 5,000 samples from 15- 18 body parts of 242 voluntary subjects, and found that more than 10000 kinds of microorganisms would migrate into the human body, and the preliminary genome sequencing of more than 800 kinds of bacteria has been completed (the final goal is to complete the genome sequencing of 3,000 kinds of bacteria). In this process, the research team found that human microbial flora contributed many genes indispensable for human survival, and the number even exceeded more than 20,000 genes owned by human beings. Obviously, we are not generous hosts who provide shelter for these microorganisms, but dependent people who have to rely on these migrating bacteria to survive!

Leisure of Enterobacteriaceae: POKEMON GO has no nucleus, and its genetic material presents as a mass of DNA in the cytoplasm. However, bacteria also have a unique ability, that is, they can capture various DNA fragments from the environment and embed them into their own genomes, or obtain plastids (pla *** id, a circular DNA with genes or other genetic factors) from other bacteria and store them in the nucleus, thus obtaining various genes. Another important discovery of HMP research team is that human intestinal bacteria also release and capture various genes in the intestine, which means that intestinal bacteria have been playing in our intestines for thousands of years before POKEMON Go swept the world.

For example, studies have shown that some intestinal bacteria in Japan carry enzymes that digest algae, and this gene comes from marine bacteria parasitic on red algae [Note 9]. North American residents who don't eat seaweed, even if they have the same intestinal bacteria, will not carry the enzyme genes that digest seaweed. Although this gene capture mechanism can quickly upgrade the intestinal bacteria in our body and add new functions, it also causes many hidden concerns; For example, epidemiologists are worried that Enterobacter may acquire drug-resistant genes or transgenic crops, thus posing a serious threat to human health and public health.

Enlightenment from Fiji 20 1 1 year, Ilana Brito, a postdoctoral fellow at Columbia University in the United States, went to Fiji and completed an impossible task: setting up Fiji Community Microbiology Project (Fiji Comp) on her own. Dr. brito brought three liquid nitrogen freezers, each weighing 15kg. It took only six weeks to get samples of 300 volunteers from four remote villages. In contrast, HMP has a collection team of more than 10, but it took three years to collect samples from 242 American subjects. Dr brito's feat has brought an unprecedented treasure house for the genetic analysis of human microbial flora. Because Fijians live in a big family, there is not much communication between villages and their diet is simple, so it is very suitable for studying the flow of intestinal bacterial genes between bacteria and people.

In the summer of 20 16, Dr. brito's first related research was published in the internationally renowned journal Nature [note 10], which contained two major discoveries. The first discovery is that the gene expression of intestinal bacteria varies with different diets. For example, in rural areas where the diet is mainly taro and bananas, the intestinal bacteria of villagers will try their best to capture the genes that digest and decompose starch, so as to obtain nutrition from the food in the intestines. In contrast, the overall flora of villagers in fishing villages is similar to that of rural villagers, but the genes captured by intestinal bacteria will be different because of different diets.

Another worrying finding is that most intestinal bacteria in Fiji are drug-resistant. This may be because antibiotics are actually substances secreted by bacteria to fight against other bacteria. Brito also analyzed bacteria from Fiji that can produce natural cephalosporins (a commonly used broad-spectrum antibiotic). The researchers concluded that this antibiotic-producing strain may enter the human intestine because people grow or eat root crops and then secrete antibiotics to crowd out other strains; This process may screen out bacteria that are already resistant, and then the drug-resistant genes of these bacteria are captured by other bacteria, and the bacteria that have captured the drug-resistant genes can survive better in the intestines ... If this cycle continues, everyone's intestines will eventually have drug-resistant bacteria. However, once human beings are infected by bacteria, these drug-resistant genes will have the opportunity to transfer from intestinal bacteria to pathogenic bacteria, forming drug-resistant superbacteria.

At present, Dr. brito, an assistant professor at Broad Institute, an important gene research center in the United States, is also working with students and colleagues to study how to regulate the gene capture preference and gene expression of intestinal bacteria through natural methods, hoping to find ways to promote the good and suppress the evil, and apply them to clinical treatment.

Reflection on "What you eat supplements what you eat" There has been a saying in Chinese medicine since ancient times that "what you eat supplements what you eat", and there is also an old saying in the West that "what you eat is what you eat". These concepts have also been confirmed by Dr. brito's research. In recent years, there have been many food safety incidents in Taiwan Province Province, which makes people think that when people normally eat heavy metals, dioxins, malachite green, dead animals, preservatives, antibiotics, clenbuterol, bleach, pesticides, flavors, edible oil, melamine, plasticizers, toxic starch, toxic soy sauce, expired food, unpalatable oil, meat water-retaining agent, industrial raw materials, etc., intestinal bacteria will tend to catch those genes. What effect will it have on the whole intestinal flora and the number of bacteria?

For example, perhaps the genes expressed or metabolites secreted by intestinal bacteria to resist the above additives will increase the risk of colorectal cancer [Note 1 1,12]; In recent years, the incidence of colorectal cancer in Taiwan Province Province has really increased rapidly, and it is younger. Perhaps in the future, Dr. brito's research can lead to a therapy that can directly optimize the gene status of intestinal bacteria, but before this miracle happens, we should try our best to adjust the most fundamental diet and living habits to ensure that intestinal bacteria will only capture super genes that can promote health!

Note: * The "cells" mentioned here refer to cells with genetic material and division ability, so reproductive factors such as red blood cells, platelets and other blood cells without nuclei and eggs that cannot divide and reproduce independently are not included in the total number of human cells. However, the total number of cells here includes neurons with very limited dividing ability. * * The so-called "metaplasia" means that alien bacteria colonize and reproduce in a certain part of the human body, but reach a state of balance with human cells, which will not trigger an immune response or destroy human cells, and may even provide many positive benefits. When the human body's immunity is low, it is also possible to multiply in large numbers and form an infection phenomenon.

References: 1. Humans carry more bacterial cells than humans. Scientific American 2007; Scientific American/article/Strange but real human beings carry more bacterial cells than human beings/2. Sender R et al. revised the estimate of the number of human and bacterial cells in the human body. On the preprint of bioRxiv 20 15; dx.doi/ 10. 1 10 1/036 103 3。 Scientists have broken the myth that there are more bacteria in our bodies than human cells. Natural 2016; Dx.doi/10.1038/nature. Schmidt K et al. The intake of prebiotics reduces the cortisol response of healthy volunteers when they are awake, and changes their emotional deviation. Psychopharmacology (BERL) 2015; 232: 1793-80 1.5. Eating fermented dairy products containing probiotics can regulate brain activity. Gastroenterology 2013; 144:1394-401.6. Collective unconsciousness: how intestinal microorganisms shape human behavior. Psychiatric research 2015; 63: 1-9.7. dagnino v & Salvatore F. The role of intestinal microflora in healthy state. Journal of Clinical Chemistry 2015; 45 1(Pt A):97- 102。 8.PJ et al.' s Human Microbiology Project: Exploring our own microbial parts in a changing world. Nature 2007; 449: 804- 10.9. Heheman JH and others transferred carbohydrate active enzymes from marine bacteria to Japanese intestinal microflora. Natural 2010; 464:908- 12. 10. The movable genes in human microbiome are constructed from the whole to the individual scale. Natural 2016; 535:435-9. 1 1. Microbial death and colon cancer: Can colon cancer be considered as a bacterial-related disease? Treat Adv gastrointestinal 2013; 6:2 15-29. 12. Zhang et al. Effects of intestinal bacteria on human health and diseases. int J Mol Sci 20 15； 16: 7493-519.13. Alison Abbott (20 16), scientists broke the myth that there are more bacteria in our bodies than human cells. Natural news.

This article is reproduced from: GENEONLINE, the most professional media team in the field of genetics.

Subject: DNA, respiratory tract, gene, gene detection, gene technology, cells, intestinal bacteria