Reference materials Gene science The difference between conjugation, transformation, transfection, and transduction. The terms conjugation, transformation, transfection, and transduction will be encountered by those who study in the field of life sciences, especially those who study microscopic life sciences. There are some explanations of these terms in textbooks and other references. I think the following explanations clearly distinguish the relationship between conjugation, transformation, transfection, and transduction! It has high reference value. If anyone has a better explanation, please share it! Conjugation, transformation, transfection, transduction, infection, etc. are several concepts related to gene (mainly DNA) transfer. 1. Conjugation is translated as "combination" in Chinese. Explanation: conjugation occurs in prokaryotes. The key to this definition is " thepiluscontracts, pullingthetwocellsintocontact¡± this direct contact between cells. When bacteria are in conjugation, a conjugation tube is formed where the two cells are in direct contact. Single-stranded DNA can be transferred directly through this channel. The formation of this channel requires corresponding gene expression (such as pilin forming sexpil. Normally, conjugation transfer is with conjugation Plasmid of necessary genes, but in a few cases this plasmid is integrated into the bacterial chromosome, chromosomal transfer may occur (the strain integrating conjugative plasmid in this chromosome is called high frequency recombination, hfrstrai single-stranded transfer is completed, the donor and recipient cells are respectively Synthesize complementary strands to complete conjugation. 2. Transformation is translated as "transformation" in Chinese. Explanation: In the definition of transformation in prokaryotes, the key word is freedna, that is to say, it is naked DNA itself, not transferred to the pronucleus through other media (such as viruses) In living things. Under natural circumstances, the DNA released by certain bacteria after dissolution is absorbed by other bacteria and transformed. Although this naturally occurring transformation is a major discovery in microbial genetics, its actual significance may not be great. Now When we talk about transformation, we generally mean that DNA molecules purified from bacteria in the laboratory are directly introduced into bacteria with different genetic characteristics. For example, plasmid transformation, we use the purified plasmid DNA itself without the help of any media. From this concept In terms of the connotation, as long as the DNA enters the bacteria, the transformation process is completed, so it does not involve whether the transformed DNA replicates, whether the genetic traits of the bacteria are changed, whether the protein is expressed, etc. Although the transformation is successful, most of it can only be determined by whether the DNA is This is achieved by changing the genetic traits of bacteria. In eukaryotes, the same process as the transformation of prokaryotes is called: 3. transfection in Chinese is translated as "transfection". For eukaryotes, transfection is the process of transformation in prokaryotes. Synonyms. The reason why the word transfection is used instead of transformation in eukaryotes is because people have been accustomed to using the word transformation to mean that eukaryotic cells become malignant cells. In prokaryotes, the word transfection is occasionally used. When the exogenous DNA absorbed during the transformation process of bacteria is viral DNA, the process should be called transfection. 4. Transduction is translated as "transduction" in Chinese. Transduction refers to the transfer of DNA from one host to another through a virus. The phenomenon of genetic recombination caused in the cells of a host. If the donor dna does not recombine with the recipient dna, the transduction process is called abortive transduction. The concept of transduction has three key words: virus, host dna, and integrate. ). First of all, transduction is generally used to describe gene transfer that occurs through viruses; secondly, what is transferred must be the host's DNA. When a virus is infected, a lot of viral DNA may be integrated into the recipient genome. If there is no virus other than the virus, Host DNA, this process cannot be called transduction. Under natural circumstances, some viruses recombine with host DNA to form new viral genomes, which are packaged and then infect other cells, resulting in transduction. In experimental research, genetic recombination is commonly used to insert target DNA into the viral genome to achieve transduction of the target gene. Finally, this DNA must be integrated into the genome of the new host cell to achieve transduction. The English above is very clear and will not be explained again. It should be noted in particular that the concept of transduction applies to prokaryotes and eukaryotes, and its connotation is exactly the same. In prokaryotes, transduction occurs naturally in several species of bacteria (desulfovibrio, escherichia, pseudomonas, rhodocous, rhodobacter, salmonella, staphylocous and xanthobacter) and in the archaea methanothermobacterthermoautotrophicu which is further divided into generalized transduction (generalized transduction) by completely defective phages Transduction is a phenomenon in which the genetic traits of the donor bacterium are transferred to the recipient bacterium by "mispackaging" any small DNA fragments of the donor bacterium; restricted transduction carries a small number of specific genes of the donor bacterium to the recipient bacterium through partially defective temperate phages. In the recipient bacteria, the transduction phenomenon of expression is obtained. Related to transduction is another concept 5. Infection Description of infection: It has been made clear before that gene transfer through viruses is called transduction. Why do we still talk about the concept of infection? This is also something that many people don¡¯t understand correctly. In fact, what we call transduction refers to the transfer process of the target gene (host DNA). The main body is the target gene, but the means to achieve transduction is viral infection, and the main body here is the viral vector. So we can say this: through retroviral infection, the ada gene is transduced into hematopoietic stem cells. But we cannot say this: through reverse transcriptionViral transduction infects the ada gene into hematopoietic stem cells. ! ~!