微生物英文名词解释

微生物英文名词解释 华中农业大学微生物试题集(仅参 考)*不做重点* Section 1 Microorganisms and Microbiology 1Archaea : a group of phylogenetically related prokaryotes distinct from Bacteria 2Bacteria :a group of phylogenetically related prokaryotes distinct from Archaea 3 Chromosome: a genetic element carrying genes essential to cell function 4DNA :deoxyribonucleic acid, the hereditary material of cells and some viruses 5 Enrichment culture :a method for isolating microorganisms from nature using specific culture media and incubation conditions 6 Enzymes :protein catalysts that function to speed up chemical reactions 7 Eukaryote :a cell possessing a membrane-enclosed nucleus and usually other organelles 8Genetics :heredity and variation of living organisms 9Microorganism :a microscopic organism consisting of a single cell or cell cluster, including the viruses 10 Plasmid :a small genetic element that exists separately from the chromosome 11Pure culture :a culture containing a single kind of microorganism 12Spontaneous generation :the hypothesis that living organisms can originate from nonliving matter 13Aseptic :technique methods for maintaining sterile culture media and other sterile objects free from microbial contamination during manipulations 14Cell :the fundamental unit of living matter 15Cytoplasm :the fluid portion of a cell, bounded by the cell membrane but excluding the nucleus (if present) 16Ecology :the study of organisms in their natural environments 17 Entropy: a measure of the degree of disorder in a system; entropy always increases in a closed system 18Eukarya :all eukaryotic organisms 19Evolution :change in a line of descent over time leading to the production of new species or varieties within a species 20Metabolism :all biochemical reactions in a cell 21 Pathogen :a disease-causing microorganism 22 Prokaryote :a cell lacking a nucleus and other organelles 23 RNA :ribonucleic acid, involved in protein synthesis as messenger RNA, transfer RNA, and ribosomal RNA 24 Sterile :absence of all living organisms and viruses Section 2 Cell Biology 1Antigen-Binding Cassette transporter :a membrane transport system consisting of three proteins, one hydrolyzes ATP as an energy source to drive the transport event, one binds the substrate on the outside of the cell, and one functions as the transport channel through the membrane 2Chloroplast :the chlorophyll-containing photosynthetic organelle of eukaryotic photosynthetic organisms 3 Cytoplasmic :membrane the permeability barrier of the cell, separating the cytoplasm from the environment 4 Eukaryote :a cell containing a membrane-enclosed nucleus and usually other organelles 5Gas vesicles :gas-filled cytoplasmic structures bounded by protein and coriferring buoyancy on cells 6 Gram-positive :a prokaryotic cell whose cell wall consists chiefly of peptidoglycan and lacks the outer membrane of gram-negative cells 7Lipopolysaccharide (LPS): lipid in combination with polysaccharide and protein forming the major portion of the cell wall in gram-negative Bacteria 8 Mitochondrion (mitochondria):an organelle found in most eukaryotic cells in which respiration and energy generation occurs 9Nucleus: a membraned-enclosed structure in cells of Eukarya that contains the genetic material, arranged in chromosomes 10 Flagellum: Peptidoglycan :a polysaccharide composed of alternating repeats of acetylglucosamine and acetylmuramic acid with the latter in adjacent layers cross-linked by short peptides 11 Peritrichous :in reference to flagellation pattern; flagella located in many places around the surface of the cell Phototaxis movement of an organism toward light 12 Prokaryote :a cell that lacks a membrane-enclosed nucleus and that usually has a single circular DNA molecule as its chromosome 13 Ribosome :small particles composed of RNAs and proteins that function in protein synthesis 14Chemotaxis :movement of an organism toward (positive) or away from (negative) a chemical gradient 15Chromosome :a DNA molecule, usually circular in prokaryotes and linear in eukaryotes, carrying genes essential to cellular function 16Endospore: a highly heat-resistant, thick-walled, differentiated cell produced by certain gram-positive Bacteria 17 Flagellum : a long, thin cellular appendage capable of rotation in prokary otic cells and responsible for swim-ming motility 18 Gram-negative :a prokaryotic cell whose cell wall contains relatively little peptidoglycan but contains an outer membrane composed of lipopolysaccharide, lipoprotein, and other complex macromolecules 19 Group translocation :an energy-dependent transport process in which the substance transported is chemi-cally modified during the transport process 20 Magnetosomes :particles of magnetite (Fe3O4) organized into nonunit membrane-enclosed structures in the cytoplasm of magnetotactic Bacteria 21 Nucleoid :an aggregated state of the circular chromosome of prokaryotic cells 22 Organelle: a unit membrane-enclosed structure found in the cytoplasm of eukaryotic cells 23Periplasm :a gellike region between the outer surface of the cytoplasmic membrane and the inner surface of the lipopolysaccharide layer of gram-negative Bacteria 24 Poly-P-hydroxybutyrate (PHB):a common storage material of prokaryotic cells consisting of a polymer of P-hydroxybutyrate or another 3-alkanoic acid 25 Protoplast :an osmotically protected cell whose cell wall has been removed Section3 Prokaryotic Microorganisms 1 Acid fastness :a property of Mycobacterium species in which cells stained with the dye basic fuchsin resist decolorization with acidic alcohol 2Chemolithotrophs :organisms able to oxidize inorganic compounds as energy sources 3 Consortia :two or more-membered association of prokaryotes, usually living in an intimate symbiotic fashion 4Enteric bacteria : a large group of gram-negative rod-shaped Bacteria characterized by a facultatively aerobic metabolism 5 Heliobacteria: anoxygenic phototrophs containing bacteriochlorophyll g 6Heterocyst : a differentiated cyanobacterial cell that carries out nitrogen fixation but not oxygenic photosynthesis 7Homofermentative : in reference to lactic acid bacteria, producing only lactic acid as a fermentation product 8 Methylotroph :an organism capable of oxidizing organic compounds that do not contain carbon-carbon bonds; if able to oxidize CH4, also a methanotroph 9 Purple nonsulfur bacteria: a group of phototrophic prokaryotes containing bacteriochlorophylls a or b that grow best as photoheterotrophs and have a relatively low tolerance for H2S 10 Prostheca :an extrusion of cytoplasm often forming a distinct appendage, bounded by the cell wall 11 Pseudomonad: member of the genus Pseudomonas, a large group of gram-negative, obligately respiratory (never fermentative) Bacteria 12 Spirochete :a slender, tightly coiled gram-negative prokaryote characterized by possession of axial filaments used for motility 13 Sulfate-reducing bacteria :a large group of anaerobic Bacteria that respire anaerobically with SO42- as electron acceptor, producing H2S 14 Carboxysomes :polyhedral cellular inclusions of crystalline ribulose bisphosphate carboxylase (RubisCO), the key enzyme of the Calvin cycle 15Chlorosomes : cigar-shaped structures bounded by a nonunit membrane and containing the light-harvesting bacteriochlorophyll (c, d, or e) in green bacteria and Chloroflexus 16 Cyanobacteria :prokaryotic oxygenic phototrophs that contain chlorophyll a and phycobilins but not chlorophyll b 17 Green bacteria: anoxygenic phototrophs containing chlorosomes and bacteriochlorophyll c, cs, d, or e as light-harvesting chlorophyll 18 Hyperthermophile: an organism with a growth temperature optimum of greater than 80oC 19Heterofermentative : in reference to lactic acid bacteria, capable of making more than one fermentation product 20 Methanotroph :an organism capable of oxidizing methane (CH4) 21 Nitrifying bacteria: chemolithotrophs capable of carrying out the transformation NH3?NO2- or NO2-?NO3- 22 Prochlorophyte :a prokaryotic oxygenic phototroph that contains chlorophylls a and b but lacks phycobilins 23 Proteobacteria :a major lineage of Bacteria that contains a large number of gram-negative rods and cocci 24Purple sulfur bacteria :a group of phototrophic prokaryotes containing bacteriochlorophylls a or b and characterized by the ability to oxidize H2S and store elemental sulfur inside the cells (or in the genus Ectothiorhodospira, outside the cell) 25 Stickland reaction :fermentation of an amino acid pair in which one amino acid serves as an electron donor and a second serves as an electron acceptor Section4 Eukaryotic Microorganisms 1Ameboid movement : a type of motility in which cytoplasmic streaming moves the organism forward 2Chloroplast: the photosynthetic organelle of eukaryotic phototrophs 3 Conidia :asexual spores of fungi 4Flagellates : a group of protozoa characterized by motility driven by the whiplike action of one or more long,thin appendages called flagella 5 Hydrogenosome: an organelle of endosymbiotic origin present in certain anaerobic eukaryotic microorganisms that functions to oxidize pyruvate to H2, CO2, and acetate, along with the production of one ATP 6 Molds: filamentous fungi 7Phagocytosis : a mechanism for ingesting particulate food in which a portion of the cell membrane surrounds the particle and brings it into the cell 8 Slime molds: nonphototrophic eukaryotic microorganisms that lack cell walls and that aggregate to form fruiting structures (cellular slime molds) or masses of protoplasm (acellular slime molds) 9 Yeasts: unicellular fungi 10Chitin : a polymer of N-acetylglucosamine commonly found in the cell walls of algae and fungi 11 Ciliates: a group of protozoa characterized by rapid motility driven by numerous short appendages called cilia 12 Eukarya :all eukaryotic organisms 13Fungi : nonphotosynthetic eukaryotic microorganisms that contain rigid cell walls 14 Mitochondrion: the respiratory organelle of eukaryotic organisms 15 Mushrooms :filamentous fungi that produce large, often edible structures called fruiting bodies 16 Protozoa :unicellular eukaryotic microorganisms that lack cell walls 17 Sporozoa :nonmotile parasitic protozoa Section 5 Viruses 1Bacteriophage: a virus that infects prokaryotic cells 2Lysogen: a bacterium containing a prophage 3Oncogene: a gene whose expression causes formation of a tumor 4Plus (positive)-strand nucleic acid :an RNA or DNA strand that has the same sense as the mRNA of a virus 5Provirus (prophage): the genome of a temperate virus when it is replicating with, and usually integrated into,the host chromosome 6Reverse transcription: the process of copying information found in RNA into DNA 7Transformation :a process by which a normal cell becomes a cancer cell (but see alternative usage in Chapter 9) 8Virulent virus: a virus that lyses or kills the host cell after infection; a nontemperate virus 9Minus (negative)-strand nucleic acid: an RNA or DNA strand that has the opposite sense of (is complementary to) the mRNA of a virus 10Plaque: a zone of lysis or cell inhibition caused by virus infection of a lawn of sensitive cells 11Prion: an infectious agent whose extracellular form may contain no nucleic acid 12 Retrovirus:a virus whose RNA genome has a DNA in-termediate as part of its replication cycle 13Temperate virus :a virus whose genome is able to replicate along with that of its host and not cause cell death in a state called lysogeny 14 Virion:the complete virus particle; the nucleic acid surrounded by a protein coat and in some cases other material 15Virus: a genetic element containing either RNA or DNA that replicates in cells but is characterized by having an extracellular state Section 6 Nutrition and Metabolism 1Activation Energy energy the energy required to bring substrates to the reactive state 2 Anabolism: the sum total of all biosynthetic reactions in the cell 3 Catabolism: biochemical reactions leading to the production of usable energy (usually ATP) by the cell 4 Chemoorganotroph :an organism that uses organic chemicals as energy sources (electron donors) 5 Coenzyme :a small nonprotein molecule that participates in a catalytic reaction as part of an enzyme 6 Culture medium :an aqueous solution of various nutrients suitable for the growth of microorganisms 7 Electron acceptor: a substance that can accept electrons from some other substance, thereby becoming reduced in the process 8 Enzyme: a protein that has the ability to speed up (catalyze) a specific chemical reaction 9 Free energy :(G) energy available to do work 10 Phototroph :an organism capable of using light as an energy source 11 Reduction potential :the inherent tendency (measured in volts) of a compound to donate electrons 12Siderophores : iron chelators that can bind iron present at very low concentrations 13 Aerobe :a microorganism able to use O2 in respiration 14 Autotroph :an organism capable of biosynthesizing all cell material from CO2 as the sole carbon source 15 Chemolithotroph: an organism that uses inorganic chemicals as energy sources (electron donors) 16 Citric acid cycle :a cyclical series of reactions resulting in the conversion of acetate to two CO2 17 Complex medium: a culture medium composed of digests of chemically undefined substances such as yeast and meat extracts 18 Defined medium :a culture medium whose precise chemical composition is known 19 Electron donor: a substance that can donate electrons to some electron acceptor, thereb y becoming oxidized in the process 20 Fermentation :anaerobic catabolism in which an organic compound serves as both an electron donor and an electron acceptor and in which ATP is produced by sub-strate-level phosphorylation 21 Oxidative phosphorylation: the production of ATP at the expense of a proton motive force formed by electron transport 22Proton motive force : an energized state of the membrane resulting from the separation of charge and the elements of water (H+ versus OH?) across the membrane 23Respiration : the process in which a compound is oxidized with O2 or an O2 substitute functioning as the terminal electron acceptor, usually accompanied by ATP production by oxidative phosphorylation 24 Substrate-level phosphorylation :production of ATP by the direct transfer of a high energy phosphate molecule from a phosphorylated organic compound to ADP Section 7 Microbial Growth and Growth Control 1 Acidophile: an organism that grows best at low pH 2 Alkaliphile :an organism that grows best at high pH 3Batch culture : a closed-system microbial culture of fixed volume 4 Compatible solute: a molecule that is accumulated in the cytoplasm for adjustment of water activity but that does not inhibit biochemical processes 5 Extremophile: an organism that grows optimally under one or more chemical or physical extremes, such as high or low temperature or pH 6 Generation time: the time required for a population of microbial cells to double 7 Halophile: a microorganism that requires NaCI for growth 8 Lag phase: a period preceding the exponential growth phase when cells may be metabolizing but are not yet growing 9 Mesophile: an organism that grows best at temperatures between 20 and 45oC 10 Psychrophile: an organism with a growth temperature optimum of 15oC or lower and a maximum growth temperature below 20oC 11 Stationary phase: the period immediately following exponential growth when the growth rate of the population falls to zero 12Viable : capable of reproducing 13 Aminoglycosides :a group of antibiotics, including streptomycin, containing amino sugars linked by glycosidic bonds 14 Antibiotic resistance :the acquired ability of a microorganism to grow in the presence of an antibiotic to which the microorganism is usually sensitive 15Antiseptic :antimicrobial agents that are sufficiently nontoxic to be applied on living tissues 16β-Lactam antibiotics: a group of antibiotics, including penicillin, that contain the four-membered heterocyclic β-lactam ring 17 Bacteriostatic: inhibits bacterial growth 18 Decontamination: treatment that renders an object or inanimate surface safe to handle 19 Disinfection: the process of eliminating nearly all pathogens, but not all microorganisms, from inanimate objects or surfaces 20 Inhibition: the reduction of microbial growth because of a decrease in the number of organisms present or alterations in the microbial environment 21 Lysis: loss of cellular integrity with release of cytoplasmic contents 22 Semisynthetic penicillin :a natural penicillin that has been chemically altered 23 Tetracycline: an antibiotic characterized by a four-mem-bered naphthacene ring 24 Aerobe: an organism that can use O2 in respiration; some require O2 for growth 25 Anaerobe :an organism that cannot use O2 in respiration and whose growth may be inhibited by O2 26 Chemostat: a device that allows for the continuous culture of microorganisms in which both growth rate and cell number can be controlled independently 27 Exponential growth: growth of a microorganism where the cell number doubles within a fixed time period 28 Facultative: with respect to O2, an organism that can grow in either its presence or absence 29Growth : an increase in cell number 30 Hyperthermophile: a microorganism that has a growth temperature optimum of 80oC or greater 31 Lysis: loss of cellular integrity with release of cytoplasmic constituents 32 Microaerophile: an aerobic organism that can grow only when oxygen tensions are reduced from that in air 33Psychrotolerant : an organism capable of growth at low temperatures but whose growth temperature optimumis above 20oC 34 Thermophile: an organism whose growth temperature optimum lies between 45 and 80oC 35 Xerophile: an organism that is able to live, or that lives best, in very dry environments 36Antibiotic : a chemical substance produced by a microorganism that kills or inhibits the growth of another microorganism 37 Antimicrobial agent: a chemical that kills or inhibits the growth of microorganisms 38 Autoclave: a sterilizer that destroys microorganisms with temperature and steam under pressure 39 Bacteriocidal: kills bacteria 40 Chemotherapeutic agent: an antimicrobial agent that can be used internally 41 Disinfectant: an antimicrobial agent used only on inanimate objects 42 Growth factor analog :a chemical agent that is related to and blocks the uptake of a growth factor 43Interferons : host-specific antiviral proteins, produced by virus-infected cells, which prevents viral infection of neighboring cells 44 Pasteurization: destruction of all disease-producing microorganisms or a reduction in the number of spoilage microorganisms 45 Sterilization: the killing or removal of all living organisms and their viruses from a growth medium Section 8 Microbial Genetics 1Auxotroph :an organism that has developed a nutritional requirement through mutation 2 Diploid:a eukaryotic cell or organism containing two sets of chromosomes 3 Electroporation:the use of an electric pulse to induce cells to take up free DNA 4Genetic map: the arrangement of genes on a chromosome 5 Genotype:the precise genetic makeup of an organism 6 Mutagens:agents that cause mutation 7 Mutation:an inheritable change in the base sequence of the genome of an organism 8 Plasmid:an extrachromosomal genetic element that has no extracellular form 9 Recombination:the process by which parts or all of the DNA molecules from two separate sources are exchanged or brought together into a single unit 10Selection: placing organisms under conditions where the growth of those with a particular genotype will be favored 11Transformation: transfer of bacterial genes involving free DNA (but see alternative usage in Chapter 8) 12Conjugation: transfer of genes from one prokaryotic cell to another by a mechanism involving cell-to-cell contact and a plasmid 13Transposon :a type of transposable element that carries genes in addition to those involved in transposition 14Gametes: in eukaryotic organisms, the haploid germ cells resulting from meiosis 15 Genome:the total complement of genes of a cell or a virus 16 Haploid:a cell or organism that has only one set of chromosomes 17Mutant: an organism whose genome carries a mutation 18 Phenotype:the observable characteristics of an organism 19 Point mutation:a mutation that involves one or only a very few base pairs 20 Screening:any of a number of procedures that permit the sorting of organisms by phenotype or genotype, but allow the growth of those possible 21 Transduction:transfer of host genes from one cell to another by a virus 22Transposable element: a genetic element that has the ability to move (transpose) from one site on a chromosometo another Section 9 Microbial Ecology 1Acid mine drainage :addic water containing H4SO4 derived from the microbial oxidation of iron sulfide minerals 2Bacteroid: morphologically misshapen Rhizobium cells inside a leguminous plant root nodule; can fix N2 3Barophilic: an organism that grows best when placed under a pressure greater than 1 atm 4 Biofilm:colonies of microbial cells encased in slime and attached to a surface 5 Black smoker:an extremely hot (250-350oC) deep-sea hot spring emitting both hot water and various minerals 6 Ecosystem:a community of organisms and their natural environment 7FISH :fluorescent in situ hybridization 8Hydrothermal vent :a deep-sea warm or hot spring, Infection thread in the formation of root nodules, a cellulosic tube through which Rhizobium cells can travel to reach and infect root cells 9 Interspecies hydrogen transfer:the production and subsequent consumption of H2 by different groups of microorganisms that interact closely during anaerobic catabolism 10 Lichen:a fungus and an alga (or cyanobacterium) living in symbiotic association 11 Microenvironment:the immediate environmental surroundings of a microbial cell or group of cells 12Optical tweezers :a laser microscope able to trap single cells and remove them from a cell mixture 13Primary producer :an organism that uses light to synthesize new organic material from CO2 14Reductive dechlorination :removal of Cl as Cl? from an organic compound by reducing the carbon atom from C?Cl to C?H 15Root nodule: a tumorlike growth on plant roots that contains symbiotic nitrogen-fixing bacteria 16 Ti plasmid:a conjugative plasmid present in the bacterium Agrobacterium tumefaciens that can transfer genes into plants 17Anoxic:, 18Xenobiotic :a totally synthetic product not naturally occurring in nature 19Barotolerant :an organism that can grow under elevated pressures but that grows best at atmospheric pressure 20 Biogeochemistry:study of biologically mediated chemical transformations 21 Cometabolism:metabolism of a compound in the presence of a second organic compound, which is used as the primary energy source 22 Enrichment culture:a means of obtaining cultures of microorganisms from a natural environment by using highly selective culture methods 23 Guild:a population of metabolically related microorganisms 24In situ: in the environment 25 Leaching:solubilization and removal of metals from an ore by microbial attack 26Microbial plastics: biodegradable polymeric materials obtained from microorganisms that have properties similar to those of synthetic plastics 27 Mycorrhiza:a symbiotic association between a fungus and the roots of a plant 28Oxic:, 29 Pyrite:a common iron-containing ore, FeS2 30Rhizosphere: the region immediately adjacent to plant roots 31Rumen: the first vessel in the multichambered stomach of ruminant animals in which cellulose digestion occurs