微生物英文名词解释1.Mycoplasma：The mycoplasma are a group of the smallest organisms withoutcell wall that can be free-living in nature, can pass through bacterial filter and also grow on laboratory media.2.Chlamydia：Chlamydia are small Gram-negative bacteria which are obligateintercellular parasites like virus, but differ from them in that they have both RNA and DNA, ribosome, cell wall, and divided by binary fission.3.L forms of bacteria：In osmotically protective media, removal of the bacterialwall with lysozyme or penicillin liberate protoplasts from Gram-positive cells and spheroplasts from Gram-negative cells. If such wall-defective cells are able to grow and divide, they are called L forms. L forms are difficult to cultivate. They require a special media. Some L form can revert tothe normal bacillary form. L form in the host may produce chronic infection that are relatively resistant to antibiotic treatment.4.Capsule：Many bacteria synthesize large amounts of extracellular polymer whengrowing in their natural environments. When the polymer forms a condensed, well-defined layer closely surrounding the cell, it is called the capsule. With one known exception (the polypeptide capsule), the polymer is polysaccharide.5.Pyrogen：This is a fever-producing substance synthesized by bacteria. In fact, itis the lipopolysaccharide of Gram-negative bacteria. For the injectable medicament, it is especially important to avoid the contamination of pyrogen in the course of pharmic production.6.Exotoxin：Exotoxins are proteins produced inside Gram-positive bacteria cellsand secreted into the environment. These toxins are some of the strongest poisons known to man and cause violent reactions in host organisms.7.Endotoxin：Endotoxins are made up of lipids and carbohydrates associated withthe outer membrane of gram-negative bacteria. These toxins usually produce fever, weakness, and capillary damage.8.Disinfection: Reduce or eliminate pathogens病原体in or on inanimate无生命的objects to a safe level, which are no longer health hazard危险.9.Sterilization: A physical or chemical process that completely destroys orremoves all microbial life，including bacteria spore and viruses.10.Antisepsis: Use chemical agents to inhibit or destroy the growth ofmicroorganisms on skin or other living tissue.11.Plasmids：Plasmids are small genetic elements that replicate independently of thebacterial chromosome. Most plasmids are circular, double-stranded DNA molecules varying from 1,500 to 400,000 base pairs. Like the bacterial chromosomal DNA, they can autonomously replicate and as such are referred to as replicons.12.Transformation：It is the process by which bacteria take up fragments of nakedDNA and incorporate them into their genomes. During transformation, DNAfragments from a dead degraded bacterium bind to DNA binding proteins on the surface of a competent recipient bacterium.13.Conjugation：Conjugation is the transfer of DNA directly from a living donorbacterium to a recipient bacterium during the mating of the bacteria. A sex pilus produced by the donor bacterium (or male) binds to the recipient (or female). The sex pilus then retracts, bringing the two bacteria in contact and the transferred DNA passes through the sex pilus.14.Transduction：Transduction is mediated by a bacteriophage, which pick upfragments of DNA and package them into bacteriophage particles. The DNA is delivered to infected cells and becomes incorporated into the bacterial genomes.15.Normal flora:The various bacteria and fungi that are permanent residents ofcertain body sites, especially the skin, oropharynx, colon, and vagina.16.Dysbacteriosis：If flora disequilibrium occurs, for example, when the residentflora is disturbed, some little significant microorganisms may colonize, proliferate and produce diseases, which are called dysbacteriosis. Dysbacteriosis mainly result from long term and large bacteriosis mainly result from long term and large bacteriosis mainly result from long term and large doses antibiotics taken. Antibiotics can suppress the drug-susceptible components of fecal flora.Soon thereafter the counts of fecal flora rise again to normal or higher than normal levels, principally of organisms selected out because of relative resistance to the drugs employed. The drug susceptible microorganisms are replaced by drug-resistant ones and cause correlative disease, microbial selection and substitution.17.Toxemia：Bacteria multiply at invading location and do not enter blood stream,but the exotoxins enter blood and cause corresponding toxic symptoms.18.Endotoxemia：Gram-negative bacteria multiply at location or in blood stream,release a lot of amount endotoxin released from bacterial cell rupture.19.Protein A ：Protein A is a cell wall component of many S. aureus strains thatbinds to the Fc portion of IgG molecules except IgG3. The Fab portion of IgG bound to protein A is free to combine with a specific antigen. Protein A has become an important reagent in immunology and diagnostic laboratory technology; for example, protein A with attached IgG molecules directed againsta specific bacterial antigen will agglutinate bacteria that have that antigen(“coagglutination”). Protein A probably contributes to the virulence of S. aureus by interfering with opsonization.20.Elementary body（EB）：Elementary body（EB）are small round cells about0.2～0.4μm with an electron-dense nucleoid. They possess a cell wall. They areextracellular form and the environmentally stable infectious particle ，and metabolically inactive. The EB have a high affinity for host epithelial cells and rapidly enter them，creating a protected membrane-bound environment around the chlamydiae，and the Elementary body is reorganized into a larger one called metabolically active Reticulate body（RB）.21.Reticulate body（RB）：The intracellular large form known as the reticulate bodyMeasuring about 0.5～1μm and devoid of an electron-dense nucleoid. Itspresence will reflect the stage of replication. Within the membrane-bound vacuole，the elementary grows in size and divides into repeatedly by binary fission. Eventually，the entire vacuole becomes filled with elementary bodies derived from reticulate bodies to form a cytoplasmic inclusion. The newly formed elementary bodies may be liberated from the host cell to infect new cells. The developmental cycle takes 24-48 hours.22.nucleocapsid：The simplest of virus particles consists of a protein coat (capsid)which surrounds a strand of nucleic acid and are thus called naked viruses or nucleocapsid.23.Abortive Infections：Not all infections lead to new progeny virus. Productiveinfections occur in permissive cells and result in the production of infectious virus. Abortive infections fail to produce infectious progeny, either because the cell may be nonpermissive and unable to support the expression of all viral genes or because the infecting virus may be defective, lacking some functional viral gene.24.defective virus：A defective virus is one that lacks one or more functional genesrequired for viral replication. Defective viruses require helper activity from another virus for some step in replication or maturation. One type of defective virus lacks a portion of its genome (i.e., deletion mutant). The extent of loss by deletion may vary from a short base sequence to a large amount of the genome.Deletion mutants may arise spontaneously or may be constructed in the laboratory using biochemical techniques.25.Interferons (IFN s)：Interferons (IFN s)are proteins made and released by hostcells in response to the presence of pathogens such as viruses, bacteria, parasites or tumor cells. They allow for communication between cells to trigger the protective defences of the immune system that eradicate pathogens or tumors. 26.Antigenic drift: Antigenic drift is constantly occurring in both influenza A andinfluenza B viruses. The HA and/or NA of the new strain are sufficiently different to evade (at least partially) the pre-existing human immunity. This leads to the seasonal epidemics.27.Antigenic shift:Antigenic shift occurs only in influenza A virus. It describes theemergence of an entirely new virus sub type. When this new sub type emerges, it causes a pandemic because there is no pre-existing immunity in humans.。