生化英文名词解释

名词解释

Glossary

第一章蛋白质的结构与功能

Chapter 1 Structure and Function of Protein

peptide bond（肽键）：a covalent bond linking the α- amino group of one amino acid and theα-carboxyl group of another in a protein molecule.

peptide（肽）：a molecule containing two or more amino acids linked by peptide bond. primary structure of protein（蛋白质的一级结构）：the amino acid sequence of a polypeptide.

secondary structure of protein（蛋白质的二级结构）：the spatial arrangement of local portions of a polypeptide chain.

tertiary structure of protein（蛋白质的三级结构）：the spatial arrangement of all the atoms of a protein or a subunit.

quaternary structure of protein（蛋白质的四级结构）：the spatial arrangement of a protein that consists of more than one folded polypeptide chain or subunit.

subunit（亚基）：an individual polypeptide chain that associates with one or more separate chains to form a complete protein.

motif（模序）：a substructure formed with two or more secondary-structure peptide segments that are drawn close to each other.

domain（结构域）：a region within a protein, particularly within a large polypeptide, that functions in a semi-independent manner.

positive cooperativity（正协同效应）：an effect that the binding of one ligand to a protein facilitates the subsequent ligand binding.

allosteric effect（变构效应）：an effect that a small molecule, called an effector, noncovalently binds to a protein and alters its activity.

isoelectric point（pI）of protein （蛋白质的等电点）：the pH at which a protein has an equal number of positive and negative charges and hence bears no net charge. denaturation of protein（蛋白质变性）： the disruption of the natively folded structure of a protein caused by exposure to heat, radiation, or chemicals, or change in pH, that leads to an alteration of chemical, physical and biological properties of the

第二章核酸的结构与功能

Chapter 2 Structure and Function of Nucleic Acid

denaturation of DNA（DNA的变性）：the disruption of the native conformation of DNA by separation of the DNA double helix into its two component strands, due to heat, chemicals, or change in pH, etc.

hyperchromic effect（增色效应）：the increase in ultraviolet absorbance of a DNA while the DNA is denatured.

melting temperature（Tm, 融解温度）：the temperature corresponding to half the maximal increase in ultraviolet absorbance of a thermally denatured DNA.

annealing（退火）：the process of returning a thermally denatured DNA to its original native structure when it is cooled gradually.

第三章酶

Chapter 3 Enzymes

simple enzyme（单纯酶）：an enzyme that consists of only polypeptide chain(s). conjugated enzyme（结合酶）：an enzyme with its polypeptide portion(apoenzyme) linked to one or more substance other than amino acids, such as metals or small organic molecules.

holoenzyme（全酶）：a complete enzyme consisting of the apoenzyme portion plus the cofactor component.

essential group（必需基团）： a chemical group on the side chain of amino acid residue of an enzyme that is closely related to the activity of the enzyme.

active center / active site（活性中心）：the region of an enzyme molecule that contains the substrate binding site and the catalytic site for converting the substrate(s) into product(s).

activation energy（活化能）：the threshold energy that must be overcome to produce a chemical reaction.

absolute specificity（绝对特异性）：the extreme selectivity of an enzyme that allows it to catalyze only the reaction with a single substrate in the case of a monomolecular reaction, or the reaction with a single pair of substrates in the case of a bimolecular

relative specificity（相对特异性）：the relative selectivity of an enzyme that allows it to catalyze the reaction with one type of reactants or one type of chemical bond. stereospecificity（立体异构特异性）：the selectivity of an enzyme for a particular stereoisomer.

zymogen（酶原）：the inactive precursor of an enzyme.

zymogen activation（酶原激活）：the process in which a zymogen is converted to an active enzyme by limited proteolysis and subsequently the active center of the enzyme is formed or exposed.

isoenzyme（同工酶）：multiple forms of an enzyme that catalyze the same reaction but differ from one another in one or more of the properties, such as structural, physical, chemical and even immunological properties.

第四章糖代谢

Chapter 4 Carbohydrate Metabolism

glycolysis（糖酵解）： the anaerobic degradation of carbohydrate whereby a molecule of glucose is converted to two molecules of lactic acid.

substrate-level phosphorylation（底物水平磷酸化）：the synthesis of ATP from ADP by the phosphorylation of ADP coupled with exergonic breakdown of a high-energy organic substrate molecules.

Pastuer effect（巴斯德效应）：the phenomenon that the glycolytic pathway is inhibited under aerobic conditions.

glycogen（糖原）： a highly branched polymer of glucose residues primarily in 1,4 linkage but with 1,6 linkage at branchpoints.

gluconeogenesis（糖异生）： the synthesis of glucose or glycogen from noncarbohydrate molecules, i.e., lactic acid, glycerol, glucogenic amino acids, etc.

第五章脂类代谢

Chapter 5 Lipid Metabolism

essential fatty acids（必需脂肪酸）： the fatty acids, including linoleic acid, linolenic acid, and arachidonic acid, which can not be synthesized in the mammalian body and must be obtained from diet.

mobilization of fat（脂肪动员）： a process of lipolysis in which the fat stored in adipose tissues is converted to free fatty acids and glycerol, which are consequently released into blood so that they can be used in other tissues.

β-oxidation of fatty acid（脂肪酸的β-氧化）： a process in which a fatty acid is degraded through a sequential removal of two-carbon fragments from the carboxyl end and therefore acetyl CoA is formed as the bond between the α- and β-carbon atoms is broken.

ketone bodies（酮体）： a group of molecules, i.e., acetone, acetoacetate, and β–hydroxybutyrate, that are synthesized in the liver from acetyl CoA.

第六章生物氧化

Chapter 6 Biological Oxidation

respiratory chain （呼吸链）/ electron transfer chain（电子传递链）： a series of electron carriers responsible for the transport of reducing equivalent from metabolite to molecular oxygen, with the net results of capturing energy for use in ATP synthesis, and of the reduction of oxygen to water.

P/O ratio（P/O比值）： the number of molecules of Pi consumed in ATP formation for each oxygen atom reduced to H2O.

oxidative phosphorylation（氧化磷酸化）： the process in which the phosphorylation of ADP to yield ATP is coupled to the electron transport through respiratory chain. uncoupler（解偶联剂）： a molecule, such as dinitrophenol, that uncouples ATP synthesis from electron transport.

第七章氨基酸代谢

Chapter 7 Amino Acid Metabolism

essential amino acids（必需氨基酸）： the amino acids，including valine, leucine, isoleucine, threonine, phenylalanine, tryptophan methionine and lysine, that cannot be synthesized by animal body and must therefore be supplied by diet. transdeamination（联合脱氨基作用）： the coupled action of an aminotransferase and a glutamate dehydrogenase involved in deamination of the majority of amino acids. transamination（转氨基作用）： a reaction catalyzed by an aminotransferase, in which an amino group is transferred from an amino acid to a keto acid.

ketogenic amino acids（生酮氨基酸）： the amino acids that can be converted to ketone bodies, i.e., leucine and lysine.

glucogenic and ketogenic amino acids（生糖兼生酮氨基酸）： the amino acids, i.e., isoleucine, phenylalanine, tyrosine, threonine and tryptophan, that can be converted to either ketone bodies or carbohydrates.

one carbon units（一碳单位）/ one carbon groups（一碳基团）： organic groups, including methyl(—CH3), methylene(—CH2—), methenyl(—CH＝), formyl(—CHO) and formimino(—CH＝NH) groups, each containing only one carbon atom generated through catabolisms of some amino acids.

第八章核苷酸代谢

Chapter 8 Nucleotide Metabolism

the de novo pathway of nucleotide synthesis（核苷酸的从头合成途径）： a pathway through which nucleotides are synthesized by using simple molecules, such as ribose 5-phosphate, amino acids, one carbon units and carbon dioxide.

the salvage pathway of nucleotide synthesis（核苷酸的补救合成途径）： a pathway through which nucleotides are synthesized by using the existing nitrogenous bases or nucleosides.

第九章物质代谢的联系与调节

Chapter 9 Integration and Regulation of Metabolism

key enzyme（关键酶）/ pacemaker enzyme（限速酶）/ regulatory enzyme（调节酶）：an enzyme that sets the rate for the entire biochemical pathway, usually catalyzes the slowest and irreversible step, and can be regulated by a number of metabolites and effectors in addition to its substrates.

allosteric regulation（变构调节）： a regulatory mechanism through which a specific low-molecular-weight molecule, called an effector or a modulator, noncovalently binds to a regulatory site outside the active center of a regulatory enzyme and alters the conformation and activity of the enzyme.

chemical modification（化学修饰调节）： a regulatory mechanism through which enzyme activities are regulated by means of reversible interconversion between the active and inactive forms of the enzyme resulted from enzyme-catalyzed covalent modification

to a specific amino acid residue.

第十章 DNA的生物合成（复制）

Chapter 10 Biosynthesis of DNA (Replication)

replication（复制）：a process in which an exact copy of parental DNA is synthesized by using each polynucleotide strand of the parental DNA as templates. semiconservative replication（半保留复制）： duplication of DNA after which the daughter duplex carries one parental strand and one newly synthesized strand.

DNA polymerase（DNA聚合酶）：any of various enzymes, with the full name of DNA dependent DNA polymerase, that catalyzes the formation of polynucleotides of DNA using an existing strand of DNA as a template.

point mutation（点突变）：a mutation that causes the replacement of a single base pair with another, including nonsense mutation, missense mutation and silent mutation. frameshift mutation（框移突变）：a mutation of insertion or deletion of a genetic material that leads to a shift in the translation of the reading frame, resulting in a completely different translation.

reverse transcriptase（逆转录酶）：any of various enzymes, with the full name of RNA dependent DNA polymerase, that catalyzes the formation of polynucleotides of DNA using an existing strand of RNA as a template.

telomeres（端粒）： structures that occur at the ends of eukaryotic chromosomes that prevent the unraveling of DNA.

第十一章 RNA的生物合成（转录）

Chapter 11 Biosynthesis of RNA (Transcription)

RNA polymerase（RNA聚合酶）：any of various enzymes, with the full name of DNA dependent RNA polymerase, that catalyzes the formation of polynucleotides of RNA using an existing strand of DNA as a template.

promoter（启动子）： a DNA sequence immediately before a gene that is recognized by RNA polymerase and signals the start point of transcription.

intron（内含子）： a noncoding intervening sequence in a split or interrupted gene that is missing in the final RNA product.

exon（外显子）： the region in a split or interrupted gene that codes for RNA which end

up in the final product (e.g., mRNA).

ribozyme（核酶）：ribonucleic acid with catalytic ability whose substrate is ribonucleic acid.

第十二章蛋白质的生物合成（翻译）

Chapter 12 Biosynthesis of Proteins (Translation)

reading frame（阅读框）： a group of three nonoverlapping nucleotides that is read as

a codon during protein synthesis. The reading frame begins with the initiator codon

AUG.

molecular chaperon (分子伴侣)：a sort of intracellular conservative protein, which can recognize the unnatural conformation of peptide and assist in the accurate folding of domains or the whole protein.

signal peptide（信号肽）： a sequence of amino acid residues located at the N-terminal portion of a nascent secretory protein, which marks the protein for translocation across the rough endoplasmic reticulum.

第十三章细胞信息转导

Chapter 13 Cell Signaling

primary messenger（第一信使）： an extracellular signaling molecule that is released from the signaling cell and can regulate the physiological activity of the target cell.

secondary messenger（第二信使）： a small intracellular molecule, such as Ca2+,cAMP, cGMP, diacylglycerol (DAG), inositol triphosphate (IP3), ceramide, or arachidonic acid (AA), etc., that is formed at the inner surface of the plasma membrane in response to a primary messenger.

receptor （受体）： a molecular structure on the surface or interior of the target cell that specifically binds signaling molecule and initiates a response in the cell. ligand（配体）： a biologically active molecule that can bind to its specific receptor.

G protein （G蛋白）/ guanylate binding proteins （鸟苷酸结合蛋白）：a trimeric guanylate

binding protein in the cytoplasmic side of plasma membrane that acts as a switch to turn activities on and off by interconversion between its monomeric GTPase and

trimeric GDP binding form.

hormone response element （激素反应元件，HRE）：a specific DNA sequence that binds hormone-receptor complex; The binding of a hormone-receptor complex either enhances or diminishes the transcription of a specific gene.

第十四章血液的生物化学

Chapter 14 Biochemical Aspects of Blood

non-protein nitrogen（非蛋白氮）：nitrogen contained in urea, creatine, creatinine, uric acid, bilirubin, and ammonia.

acute phase protein（急性时相蛋白质）：a protein whose plasma concentration can be altered when acute inflammation or a certain type of tissue damage occurs.

2,3-bisphosphoglyerate shunt（2,3-二磷酸甘油支路）：the pathway in erythrocyte glycolysis in which glycerate 1,3-bisphosphate(1,3-BPG) is isomerized to 2,3-bisphosphoglyerate(2,3-BPG) and the latter is consequently hydrolyzed to form 3-phosphoglycerate. The importance of 2,3-BPG in the erythrocyte lies in its ability to alter the extent to which hemoglobin binds with oxygen.

第十五章肝的生物化学

Chapter 15 Biochemical Aspects of the Liver

biotransformation（生物转化）： a series of enzyme-catalyzed processes through which non-nutritional molecules, which are usually hydrophobic, are converted into more soluble metabolites.

jaundice（黄疸）： a clinical manifestation of hepatic disease, featuring yellow discolration of the plasma, skin, and mucous membranes, caused by bilirubin accumulation and staining.