Phage is actually a general term for bacterial viruses that infect microorganisms such as bacteria, fungi, actinomycetes or spirochetes. It was first discovered in Staphylococcus and Shigella at the beginning of this century. Phage has some characteristics of virus, and its genome contains many genes, but all known phages are various factors needed in bacterial cells. Protein is synthesized by bacterial ribosomes, various amino acids and energy generation system to realize its own growth and proliferation. Once out of the host cell, phage can neither grow nor replicate.

According to the latest news I learned, the most terrible thing is that it can pass through the filter screen of bacteria, and it has no complete cell structure, and is mainly composed of capsids containing protein and nucleic acid. It can only replicate and proliferate in living microorganisms, and it is a special intracellular parasitic microorganism. Phage is widely distributed, where there are bacteria, there may be corresponding phage. Phage of intestinal bacteria often exists in human and animal excreta or polluted well water and river water, and phage of soil bacteria can also be found in soil.

Phage has strict host specificity and only exists in the susceptible host phyllophyta. Therefore, phage can be used for epidemiological identification and typing of bacteria to trace the source of infection. Phage is a good experimental system for molecular biology and genetic engineering because of its simple structure and few genes. The life cycle of phage is dissolution or dissolution, and phage such as T4 is cracked after virus replication.

Then release the phage offspring and find a new host. Solvent phage does not immediately dissolve the host cell. These bacteriophages are called temperate bacteriophages. The phage genome is integrated with the host genome and replicated with it without destroying cells. When the conditions of host cells deteriorate, such as lack of nutrition, phages begin to multiply, which may lead to their rupture.

Finally, the analysis referred to by the above phage is here today.