微生物名词解释

Glossary Actinomycetes 放线菌 放线菌属放线菌 放线菌属 A group of filamentous funguslike bacteria active transport 主动运输 主动运输 Nutrient transport method that requires carrier proteins in the membranes of the living cells and the expenditure of energy adenovirus Noenveloped DNA virus means of transmission is human to human via respiratory and ocular secretions aerobe 需氧微生物 需氧微生物 A microorganism that lives and grows in the presence of free gaseous oxygen O2 aerobic respiration 需氧呼吸 需氧呼吸 Respiration in which the final electron acceptor in the electron transport chain is oxygen O2 agar 琼脂 琼脂 A polysaccharide found in seaweed and commonly used to prepare solid culture media AIDS 艾滋病 艾滋病 Acquired immunodeficiency syndrome The complex of signs and symptoms characteristic of the late phase of human immunodeficiency virus HIV infection algae 藻类 藻类 Photosynthetic plant like organisms which generally lack the complex structure of plants they may be single celled or multicellular and inhabit diverse habitats such as marine and freshwater environments glaciers and hot springs Ames test 艾姆斯氏试验 艾姆斯氏试验 A method for detecting mutagenic and potentially carcinogenic agents based upon the genetic alteration of nutritionally defective bacteria ammonification 氨化作用 氨化作用 Phase of the nitrogen cycle in which ammonia is released from decomposing organic material anaerobe 厌氧性微生物 厌氧菌 厌氧性微生物 厌氧菌 A microorganism that grows best or exclusively in the absence of oxygen anaerobic respiration 无氧呼吸 无氧呼吸 Respiration in which the final electron acceptor in the electron transport chain is an inorganic molecule containing sulfate nitrate nitrite carbonate etc antagonism 拮抗作用 拮抗作用 Relationship in which microorganisms compete for survival in a common environment by taking actions that inhibit or destroy another organism antibiotic 抗生素 抗生素 A chemical substance from one microorganism that can inhibit or kill another microbe even in minute amounts archaea 古生菌 古生菌 Prokaryotic single celled organisms of primitive origin that have unusual anatomy physiology and genetics and live in harsh habitats when capitalized Archaea the term refers to one of the three domains of living organisms as proposed by Woese arthrospore 分节孢子 分节孢子 A fungal spore formed by the septation and fragmentation of hyphae ascospore 囊孢子 子囊孢子 囊孢子 子囊孢子 A spore formed within a saclike cell ascus of Ascomycota following nuclear fusion and meiosis ascus 子囊 子囊 Special fungal sac in which haploid spores are created autoclave 高压锅 高压锅 A sterilization chamber which allows the use of steam under pressure to sterilize materials The most common temperature pressure combination for an autoclave is 121 and 15 psi autotroph 自养生物 自养生物 A microorganism that requires only inorganic nutrients and whose sole source of carbon is carbon dioxide Bacillus 芽孢杆菌 芽孢杆菌 Bacterial cell shape that is cylindrical longer than it is wide back mutation 回复突变 回复突变 A mutation which counteracts an earlier mutation resulting in the restoration of the original DNA sequence bacteria 细菌 细菌 Category of prokaryotes with peptidoglycan in their cell wails and a single circular chromosome This group of small cells is widely distributed in the earth s habitats Bacteria plural of bacterium When capitalized can refer to one of the three domains of living organisms proposed by Woese containing all non archaea prokaryotes bacterial chromosome 细菌染色体细菌染色体 A circular body in bacteria that contains the primary genetic material Also called nucleoid Bacteriophage 噬菌体噬菌体 A virus that specifically infects bacteria bacterium 杆菌属杆菌属 A tiny unicellular prokaryotic organism that usually reproduces by binary fission and usually has a peptidoglycan cell wall has various shapes and can be found in virtually any environment basidiospore 芽孢 芽孢 A sexual spore that arises from a basidium Found in basidiomycota fungi Bdellovibrio 蛭弧菌属蛭弧菌属 A bacterium that preys on certain other bacteria It bores a hole into a specific host and inserts itself between the protoplast and the cell wall There it elongates before subdividing into several cells and devouring the host cell capsule 蒴果蒴果 In bacteria the loose gel like covering or slime made chiefly of simple polysaccharides This layer is protective and can be associated with virulence Chemoautotroph 华能自养生物华能自养生物 An organism that relies upon inorganic chemicals for its energy and carbon dioxide for its carbon Also called a chemolithotroph chemoheterotroph 华能异养生物 Microorganisms that derive their nutritional needs from organic compounds chemotaxis 趋化性趋化性 The tendency of organisms to move in response to a chemical gradient toward an attractant or to avoid adverse stimuli chitin 几丁质几丁质 A polysaccharide similar to cellulose in chemical structure This polymer makes up the horny substance of the exoskeletons of arthropods and certain fungi chromosome 染色体 The tightly coiled bodies in cells that are the primary sites of genes Clone 无性繁殖无性繁殖 A colony of cells or group of organisms derived from a single cell or single organism by asexual reproduction All units share identical characteristics Also used as a verb to refer to the process of producing a genetically identical population of cells or genes colony 菌落菌落 A macroscopic cluster of cells appearing on a solid medium each arising from the multiplication of a single cell commensalism 共栖共栖 An unequal relationship in which one species derives benefit without harming the other conjugation 结合作用结合作用 In bacteria the contact between donor and recipient cells associated with the transfer of genetic material such as plasmids Can involve special sex pili Also a form of sexual recombination in ciliated protozoans death phase 死亡期死亡期 End of the cell growth due to lack of nutrition depletion of environment and accumulation of wastes Population of cells begins to die decomposition 分解 The breakdown of dead matter and wastes into simple compounds that can be directed back into the natural cycle of living things diffusion 扩散 The dispersal of molecules ions or microscopic particles propelled down a concentration gradient by spontaneous random motion to achieve a uniform distribution diploid 二倍体二倍体 Somatic cells having twice the basic chromosome number One set in the pair is derived from the father and the other from the mother direct or total cell count 细胞计数细胞计数 1 Counting total numbers of individual cells being viewed with magnification 2 Counting isolated colonies of organisms growing on a plate of media as a way to determine population size endospore 内生孢子 A small dormant resistant derivative of a bacterial cell that germinates under favorable growth conditions into a vegetative cell The bacterial genera Bacillus and Clostridium are typical sporeformers eubacteria 真细菌真细菌 Term used for non archaea prokaryotes stands for true bacteria eukaryotic cell 真核细胞 A cell that differs from a prokaryotic cell chiefly by having a nuclear membrane a well defined nucleus membrane bounded subcellular organelles and mitotic cell division Eukarya 真核生物 One of the three domains sometimes called superkingdoms of living organisms as proposed by Woese contains all eukaryotic organisms eutrophication 富营养化 The process whereby dissolved nutrients resulting from natural seasonal enrichment or industrial pollution of water cause overgrowth of algae and cyanobacteria to the detriment of fishand other large aquatic inhabitants fermentation 发酵发酵 The extraction of energy through anaerobic degradation of substrates into simpler reduced metabolites In large industrial processes fermentation can mean any use of microbial metabolism to manufacture organic chemicals or other products fimbria 菌毛菌毛 A short numerous surface appendage on some bacteria that provides adhesion but not locomotion flagellum 鞭毛 A structure that is used to propel the organism through a fluid environment gene 基因 A site on a chromosome that provides information for a certain cell function A specific segment of DNA that contains the necessary code to make a protein or RNA molecule generation time 代时 Time required for a complete fission cycle from parent cell to two new daughter cells Also called doubling time genome 基因组基因组 染色体组染色体组 The complete set of chromosomes and genes in an organism Genotype 基因型基因型 The genetic makeup of an organism The genotype is ultimately responsible for an organism s phenotype or expressed characteristics Gram stain 革兰氏染色剂革兰氏染色剂 A differential stain for bacteria useful in identification and taxonomy Gram positive organisms appear purple from crystal violet mordant retention whereas gram negative organisms appear red after loss of crystal violet and absorbance of the safranin counterstain growth curve 生长曲线 A graphical representation of the change in population size over time This graph has four periods known as lag phase exponential or log phase stationary phase and death phase growth factor 生长因子 An organic compound such as a vitamin or amino acid that must be provided in the diet to facilitate growth An essential nutrient halophile 好盐菌 A microbe whose growth is either stimulated by salt or requires a high concentration of salt for growth haploid 单倍体单倍体 Having a single set of unpaired chromosomes such as occurs in gametes and certain microbes host 宿主宿主 Organism in which smaller organisms or viruses live feed and reproduce human immunodeficiency virus HIV 艾滋病病毒 A retro virus that causes acquired immunodeficiency syndrome AIDS intron 内含子内含子 The segments on split genes of eucaryotes that do not code for polypeptide They can have regulatory functions See exon in vitro 离体离体 Literally means in glass signifying a process or reaction occurring in an artificial environment as in a test tube or culture medium in vivo 生物体内 Literally means in a living being signifying a process or reaction occurring in a living thing Koch s postulates 科赫法则 A procedure to establish the specific cause of disease In all cases of infection 1 The agent must be found 2 inoculations of a pure culture must reproduce the same disease in animals 3 the agent must again be present in the experimental animal and 4 a pure culture must again be obtained lag phase延迟期The early phase of population growth during which no signs of growth occur L form 缺壁细菌缺壁细菌 L phase variants wall less forms of some bacteria that are induced by drugs or chemicals These forms can be involved in infections lipopolysaceharide 脂多糖脂多糖 A molecular complex of lipid and carbohydrate found in the bacterial cell wall The lipopolysaccharide LPS of gram negative bacteria is an endotoxin with generalized pathologic effects such as fever log phase 指数期 Maximum rate of cell division during which growth is geometric in its rate of increase Also called exponential growth phase Meiosis 减数分裂减数分裂 The type of cell division necessary for producing gametes in diploid organisms Two nuclear divisions in rapid succession produce four gametocytes each containing a haploid number of chromosomes minimum inhibitory concentration MIC 最低抑菌浓度最低抑菌浓度 The smallest concentration of drug needed to visibly control microbial growth minimum temperature 最低温度 The lowest temperature at which an organism will grow missense mutation 错义突变 A mutation in which a change in the DNA sequence results in a different amino acid being incorporated into a protein with varying results mitosis 有丝分裂有丝分裂 Somatic cell division that preserves the somatic chromosome number mycelium 菌丝菌丝 菌丝体菌丝体 The filamentous mass that makes up a mold Composed of hyphae Mycorrhizae 菌根菌根 Various species of fungi adapted in an intimate mutualistic relationship to plant roots nitrification 硝化作用 Phase of the nitrogen cycle in which ammonium is oxidized nitrogen fixation 固氮作用固氮作用 A process occurring in certain bacteria in which atmospheric N2 gas is converted to a form NH4 usable by plants nonsense mutation 无义突变无义突变 A mutation that changes an amino acid producing codon into a stop codon leading to premature termination of a protein nucleus 细胞核细胞核 The central core of an atom composed of protons and neutrons obligate 专性 Without alternative restricted to a particular characteristic Example An obligate parasite survives and grows only in a host an obligate aerobe must have oxygen to grow an obligate anaerobe is destroyed by oxygen optimum temperature 最适温度 The temperature at which a species shows the most rapid growth rate parasite 寄生虫寄生虫 An organism that lives on or within another organism the host from which it obtains nutrients and enjoys protection The parasite produces some degree of harm in the host passive transport 被动运输被动运输 Nutrient transport method that follows basic physical laws and does not require direct energy input from the cell pasteurization 巴斯消毒法巴斯消毒法 Heat treatment of perishable fluids such as milk fruit juices or wine to destroy heat sensitive vegetative cells followed by rapid chilling to inhibit growth of survivors and germination of spores It prevents infection and spoilage pathogen 病原体病原体 Any agent usually a virus bacterium fungus protozoan or helminth that causes disease phage 噬菌体噬菌体 A bacteriophage a virus that specifically parasitizes bacteria phenotype 表型表型 The observable characteristics of an organism produced by the interaction between its genetic potential genotype and the environment photoautotroph 光合自养生物光合自养生物 An organism that utilizes light for its energy and carbon dioxide chiefly for its carbon needs pill Small stiff filamentous appendages in gram negative bacteria that function in DNA exchange during bacterial conjugation plasmids 质粒质粒 Extrachromosomal genetic units characterized by several features A plasmid is a double stranded DNA that is smaller than and replicates independently of the cell chromosome it bears genes that are not essential for cell growth it can bear genes that code for adaptive traits and it is transmissible to other bacteria polysaccharide 多糖多糖 A carbohydrate that can be hydrolyzed into a number of monosaccharides Examples cellulose starch glycogen prion 朊病毒朊病毒 A concocted word to denote proteinaceous infectious agent a cytopathic protein associated with the slow virus spongiform encephalopathies of humans and animals prophage 原噬菌体原噬菌体 A lysogenized bacteriophage a phage that is latently incorporated into the host chromosome instead of undergoing viral replication and lysis protoplast 原生质体原生质体 A bacterial cell whose cell wall is completely lacking and that is vulnerable to osmotic lysis protozoa 原生动物原生动物 A group of single celIed eucaryotic organisms pseudohypha 假菌丝假菌丝 A chain of easily separated spherical to sausage shaped yeast cells partitioned by constrictions rather than by septa pure culture 纯培养纯培养 A container growing a single species of microbe whose identity is known Retrovirus 逆转录酶病毒逆转录酶病毒 A group of RNA viruses including HIV that have the mechanisms for converting their genorne into a double strand of DNA that can be inserted on a host s chromosome reverse transcriptase 逆转录酶逆转录酶 The enzyme possessed by retrovimses that carries out the reversion of RNA to DNA a form of reverse transcription rhizobia 根瘤菌根瘤菌 Bacteria that live in plant roots and supply supplemental nitrogen that boosts plant growth rhizosphere 根际根际 The zone of soil complete with microbial inhabitants in the immediate vicinity of plant roots rickettsias 立克次体立克次体 Medically important family of bacteria commonly carried by ticks lice and fleas Significant cause of important emerging diseases root nodules 根瘤根瘤 Small growths on the roots of legume plants that arise from a symbiotic association between the plant tissues and bacteria Rhizobia This association allows fixation of nitrogen gas from the air into a usable nitrogen source for the plant silent mutation 同义突变同义突变 A mutation that because of tire degeneracy of the genetic code results in a nucleotide change in both the DNA and mRNA but not the resultant amino acid and thus not the protein spore 孢子孢子 A differentiated specialized cell form that can be used for dissemination for adverse conditions and or for reproduction Spores are usually unicellular and may develop into gametes or vegetative organisms stationary growth phase 稳定期稳定期 Survival mode in which cells either stop growing or grow very slowly sterilization 灭菌灭菌 Any process that completely removes or destroys all viable microorganisms including viruses from an object or habitat Material so treated is sterile strict or obligate anaerobe 严格厌氧微生物严格厌氧微生物 An organism which does not use oxygen gas in metabolism and cannot survive in oxygen s presence symbiosis 共生共生 An intimate association between individuals from two species used as