Metagenomics is a new term. Probably many people have never heard of it. Let's learn about it today.
What is the metagenome?
Metagenome (also known as microbial environmental genome Microbial Environmental Genome, or metagenomics) is a new term proposed in 1998 by Handelsman and so on. It is defined as "the genomes of the total microbiota found in nature”, that is the sum of the genetic material of all small and small organisms in the environment. It contains the genes of culturable and uncultured microorganisms, which currently refer to the total genome of bacteria and fungi in environmental samples.
About the metagenomics
Metagenomics is a study of microbial population genome in environmental samples, using functional gene screening and / or sequencing analysis as a research method, with microbial diversity, population structure, evolutionary relationships, functional activity, interaction and relationship with the environment. A new method of microbiological research for the purpose of the study. In general, genomic DNA is extracted from environmental samples, high flux sequencing analysis, or cloned DNA to suitable carrier, introduction of host bacteria, screening target transformants and so on.
The object of the study of metagenomics
The object of the study of metagenomics is the total DNA in a specific environment, not a specific microorganism or the total DNA in its cells. It does not need to separate and purify microbes. This provides a new way for us to understand and utilize more than 95% uncultured microbes. Studies have shown that the use of metagenomics to study the oral microbial flora of the human body has found more than 50 new bacteria, which are likely to be associated with oral diseases. In addition, many new microbial populations and new genes or gene clusters have been found in soil, ocean and some extreme environments, and new physiological active substances, including antibiotics, enzymes and new drugs, are obtained by cloning and screening.
The steps of the metagenomic study
①Separation of specific environmental biological DNA.
②The purified macromolecular weight DNA was cloned.
③The vectors with metagenomic DNA were transferred into the model microorganism to establish their respective asexual lines through transformation.
④The DNA of the macrogenome library was analyzed.
The development of metagenomics
The development of metagenomics has gone through 4 stages:
In 1991, the concept of environmental genomics was first proposed. In the same year, the first phage library was constructed by cloning DNA from environmental samples.
In 1998, microbial genomics proposed that the object of life study should be the genome of all tiny organisms in the biological environment. The concept of metagenome was first proposed for the study of the total genome of bacteria and fungi in specific environmental samples.
In 1998, it was proposed that the object of life study should be the genome of all tiny organisms in the biological environment. For the first time, the metagenome concept was proposed for the study of the total genome of bacteria and fungi in specific environmental samples.
In March 2007, the National Academy of Sciences, the National Academy of Sciences, published an advisory report on "the new science of environmental genomics - the mysteries of the microbiological world", pointing out that macrogenomics provides a new way to explore the mysteries of the microbiological world. This is the most important progress in the study of microbiological methods since the invention of microscopes. Revolutionary breakthrough in world awareness.
Generalized metagenomics refers to the sum of all biological genetic materials in a given environment, which determines the life phenomena of biological groups. It is a science that uses all DNA in the ecological environment as the research object, to screen useful genes and their products by cloning and heterologous expression, to study their functions and their relationship and interaction, and to reveal their laws.
Human metagenomics studies the structure and function of human macro genome, the relationship among them, the rules of action and the relationship between diseases and diseases. It not only determines the overall genome sequence information, but also studies the gene function related to human development and health.
The application of metagenomics
By means of macrogenomics and genome sequencing, the natural products in the difficult or non culture microorganism and the natural products in the "silent" state are found. Metagenomics does not depend on the isolation and cultivation of microorganisms, thus reducing the bottleneck problem. In a few years, the study of metagenomics has penetrated into various fields, from ocean to land, to air, from termites to mice, to human beings, from fermentation to bioenergy, to environmental treatment, etc.