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1、生化n解释（Biochemical n interpretation）Interpretation of biochemical termsStructure and function of proteinThe peptide bond: amide bond of a molecule of amino acid and other amino acids by carboxyl off water molecules formed afterIs called a peptide bond.Isoelectric point: the tendency or degree of diss
2、ociation of an amino acid or protein into positive ions and anions in an pH solutionAnd so on, become facultative ions, point neutral, at this time pH of the solution is called the amino acid or protein and so onElectric point.In protein molecules, two or more peptide segments with two - stage struc
3、tures are spatially adjacent to each other in two molecules,Form a special spatial conformation and play a special function called a motif.Domain: a protein with a relatively large molecular weight; the three - order structure can often be divided into a number of closely - structured regions and us
4、ed for specific purposesThe functions of these regions are called domains.Subunit: a complete three - stage structure formed by each peptide chain in the four - stage structure of a protein.Peptide unit: in peptides, 4 atoms in the peptide bond and on both sides of the carbon atoms in the same plane
5、,Peptide unit.Protein denaturation: the conformational destruction of proteins under the influence of certain physical and chemical factors, thus altering the nature of proteinsChemical properties and biological activities are called protein denaturation.Structure and function of nucleic acidDNA den
6、aturation: in the presence of some physical and chemical factors, DNA molecules are stabilized by double helix space conformation breaking and double stranded solutionsChain into two single chain, but its primary structure is still intact phenomenon called DNA degeneration.Tm: that is, the temperatu
7、re of the solution or the temperature of the chain is the maximum absorption value of the nucleic acid when the nucleic acid is heated and denaturedTemperature at 50%. At Tm, the double helix structure of the nucleic acid molecule 50% is destroyed.Enhancement effect: when the nucleic acid is heated
8、and denatured, the absorption of 260nm is increased because of the exposure of a large number of basesThe image is called the color enhancement effect.HnRNA: heterogeneous nuclear RNA. The mRNA primary product synthesized in the nucleus is more mature than the mature mRNA moleculeMuch larger, termed
9、 intranuclear heterogeneous RNA. HnRNA is present in the nucleus for a very short time and is shearedCut into mature mRNA and rely on a special mechanism to transfer into the cytoplasm.Ribozymes: also known as catalytic RNA, some RNA have catalytic capabilities that catalyze self splicing reactionsA
10、 catalytically active RNA molecule is called a ribozyme.Nucleic acid hybridization: the nucleic acid molecules of different sources but with complementary sequences, in accordance with the principle of complementation of bases, in the appropriate stripA hybrid double strand is formed. This phenomeno
11、n is called hybridization between nucleic acid molecules.enzymeEnzyme: a special class of proteins produced by living cells that have catalytic function.The active centers of the enzyme and the essential groups: the essential groups closely related to the activity of enzymes are closely related to e
12、ach other in the spatial structureA region having a specific spatial structure that can be combined with substrate and baseThis region is called the active center of the enzyme. Essential groups areOf any chemical group present in an enzyme molecule; not necessarily related to the activity of an enz
13、ymeAmong them, the groups which are closely related to enzyme activity are called the essential groups of enzymes.Activation of zymogen and zymogen: some enzymes are initially synthesized or secreted in cells, but are inactive precursors of enzymesUnder certain conditions,These enzyme precursor hydr
14、olysis of one or several specific peptide bonds, resulting in.The image changed, showing the activity of the enzyme. The precursor of this inactive enzyme is called zymogen.The conversion of zymogen to the enzyme is called zymogen activation, which is actually the active site of the enzymeThe proces
15、s of forming or exposing.Isozyme: an enzyme having the same catalytic action but different enzyme molecular structure, physical and chemical properties and immunological properties.Km value: (Michaelis Menten constant) in a single substrate reaction, the enzyme and substrate reversibly produce inter
16、mediate products and intermediates into productsThe synthesis of the rate constants of the three reactions is one of the characteristic constants of the enzyme, and its value is equal to the reaction rateThe substrate concentration is half the maximum speed.Glucose metabolismGlycolysis: the process
17、of breaking down glucose or glycogen into lactic acid under anoxic conditions.Active glucose: 1-, glucose phosphate and UTP formed by the action of UDPG is active glucose, as grapes in vivoSugar donor.Blood sugar: the glucose in the blood is called blood sugar, and the normal persons fasting blood g
18、lucose level is 3.96.1mmol/LGluconeogenesis: the process of converting non sugar substances such as amino acids, lactic acid, and glycerol into glucose or glycogen.Three: the tricarboxylic acid cycle, acetyl CoA and oxaloacetate production citric acid, after a series of reactions and formation of Ox
19、alyl BAcids produce NADH+H+, FADH2, GTP, CO2, H2O at the same time.Pasteur effect: aerobic oxidation of sugars inhibits the fermentation of ethanol and glycolysis.Lactic acid cycle: lactic acid produced by glycolysis of muscle glycogen, transported to the liver through the liver, sugar, gluconeogene
20、sis, the synthesis of liver glycogen or glucose to complementBlood sugar, blood sugar can also be used for muscle, this process is called lactic acid cycle (Cori cycle).Substrate level phosphorylation: transfers energy directly from the metabolite molecule to ADP (or GDP) and produces ATP (or GTP)Th
21、e process is termed substrate level phosphorylation.Lipid metabolismApolipoprotein: part of the plasma lipoprotein called apolipoprotein. Play a role in the transport of lipids in plasmaIt recognizes lipoprotein receptors and regulates the activity of plasma lipoprotein metabolizing enzymes.Fat mobi
22、lization: fat stored in fat cells and gradually hydrolyzed by lipase to free fatty acids and glycerol and releasedThe process of blood letting is used by other tissues for oxidation. This process is called fat mobilization.Beta oxidation of fatty acids: the oxidation of fatty acids in the body begin
23、s with the beta carbon atom at the carboxyl terminus of the fatty acidTwo carbon atoms are broken, and the whole process is called beta oxidation.Plasma lipoproteins: plasma lipids that bind to proteins and are transported in the form of lipoproteins.Ketone: acetoacetate, hydroxybutyric acid and ace
24、tone referred to the three ketone. Ketone bodies are fatty acids that are produced when they are oxidized and broken down in the liverA unique intermediate metabolite of the ovary.ACAT: acyl lipoprotein cholesterol transferase CoA. Distributed in the endoplasmic reticulum of cells and able to turn a
25、cyl groups on acyl CoATransfer to the 3 hydroxyl group of free cholesterol to make cholesterol esterified.LCAT: lecithin cholesterol acyltransferase. It catalyzes the transfer of 2 bits of lecithin to cholesterol 3The reaction of hydroxyl groups to the production of phosphatidylcholine and cholester
26、ol esters.Citrate pyruvate cycle is the process of taking acetyl CoA from mitochondria into the cytosol to synthesize fatty acids or cholesterolApproach. In this cycle,First, acetyl CoA in mitochondria and oxaloacetate condensationCitric acid is produced, and citrate is transported into the cytosol
27、through a carrier on the inner membrane of the mitochondrion;The citrate lyase in the cytosol catalyzes the cleavage of citric acid and releases acetyl CoA and Cao XianyiAcetic acid, acetyl CoA, is taken into the cytosol. Is reduced to malate oxaloacetate,.The carrier of the inner mitochondrial memb
28、rane goes back to the mitochondria. Malic acid can also be used in malic enzymeIt breaks down into pyruvate and goes into mitochondria, eventually forming the mitochondriaAcetic acid, and then participate in the transport of acetyl CoA.Biological oxidationAlpha glycerol shuttle is a way of transferr
29、ing 2 H carrying NADH in the cytosol into the mitochondria,Because the system has alpha - glyceryl phosphate, which is named alpha - glycerol phosphate shuttle.Malate aspartate shuttle: a form of NADH in the cytosol that carries the 2 H into the mitochondria,Because the system contains malic acid an
30、d aspartic acid, it is called malate aspartic acid shuttle.Respiratory chain: a pair of hydrogen ions that are stripped of the metabolite and are arranged in a series of enzymes and enzymes in the mitochondrial liningThe base is catalyzed and eventually combines with oxygen to form water; the reacti
31、on chains composed of these enzymes and prosthetic groups are called respiratory chains.Biological oxidation: the process of oxidation and decomposition of substances in organisms is called biological oxidation. It mainly refers to sugar, fatFat and protein in vivo decomposition gradually release en
32、ergy, process of generating CO2 and H2O.Oxidative phosphorylation: metabolite of 2 H in the process of coupling the phosphorylation of ADP and the generation of ATP transmission over the respiratory chainThe process, known as oxidative phosphorylation. Is the main form of ATP in the body.Amino acid
33、metabolismEssential amino acids: amino acids that cannot be synthesized by the body and must be supplied by food.Gamma glutamyl cycle is an important route for the absorption of amino acids. The reaction process consists of glutathione to ammoniaThe transport of basic acids, followed by the regenera
34、tion of glutathione, constitutes a cycle.Deamination: the interaction between a pair of amino acids and a pair of keto acids under the action of transaminase. TransaminationThe basal action is not only the catabolism of amino acids, but also the synthesis of some non essential amino acids in the bod
35、yImportant way.Combined deamination: combined deamination is an important deamination in liver, kidney, brain and other tissues,This deamination is catalyzed by transaminase, the catalytic action of the amino group, and the release of L- glutamate dehydrogenaseThe combined action of oxidative deamin
36、ation of glutamic acid was carried out.A unit of carbon containing a carbon atom produced during catabolism, called a unit of carbon, CO2Except。Reactive methionine: also known as S-, adenosine methionine (SAM), methionine and ATP, methionine glandThe enzyme catalyzes the generation of reactive methi
37、onine, which serves as a direct donor of methyl,Methylation of other substances.Nucleotide metabolismDe novo synthesis of nucleotides using small molecules such as ribose phosphate, amino acids, a carbon unit, and COThe process of synthesizing a single nucleotide through a series of complex enzymati
38、c reactions.Nucleotide: certain purine, pyrimidine, folate, and amino acid analogs that are competitively inhibitedInterfere with or block the normal synthesis of nucleotides, thereby further inhibiting nucleic acids and proteinsSynthesis and cell proliferation; these substances are nucleotide resis
39、tant metabolites.Nucleotide salvage synthesis pathway: the process of synthesizing single nucleotide by using the bases and nucleosides.The relation and regulation of substance metabolismAllosteric regulation: non catalytic partial when certain substances and enzymes with non covalent bonds form, ca
40、n change the protein moleculeThe conformation, which in turn alters the activity of an enzyme, is called allosteric regulation.Chemical modification: the enzymatic modification of certain amino acid residues on the peptide chain of proteins resulting in reversible covalent modifications catalyzed by
41、 enzymesAlteration of enzyme activity.Speed restriction enzyme: the enzyme that catalyzes the slowest rate of reaction throughout metabolism, which affects not only the whole metabolic pathwayTotal speed and metabolic direction are the key enzymes or regulatory enzymes in metabolic pathways.Biosynth
42、esis of DNADNA semi reserved replication: using two DNA single chains as templates, dNTP as raw material, and catalysis in DNA polymeraseThe process of synthesizing progeny DNA according to the principle of base complementation. Offspring DNA double strandedA chain comes from the mother chain (templ
43、ate), and the other complementary DNA chain is newly synthesized, so it is called halfKeep copy.Okazaki fragment: DNA replication process, with 5 to 3 direction DNA strand as a template, after synthesis in chain guideMany discrete segments, the phenomenon is the Japanese scientists found Okazaki Oka
44、zaki fragments, called.Leading strand and follower chain: when replicating, the DNA double chains unravel their respective directions as templates in which a strand of strand replicatesConsistent with the direction of the chain, the chain can be continuously synthesized. This chain is called a leadi
45、ng chain. Double chainIn DNA replication, the synthesis direction of one strand is opposite to the direction of the chainContinue to carry on, need to want a template to untie a paragraph, then duplicate a paragraph, call this chain as the follower chain.Excision repair of DNA: the most important an
46、d effective way to repair cells, including the removal of damaged DNAFilling gaps and connections requires specific endonucleases, DNA polymerases, and DNA linksEnzyme completion.Recombinant repair of DNA: a strand that is copied from an erroneous template for damage that is too large to be repaired
47、 in timeWith errors or even gaps. Recombinant protein RecA will be another strand of healthy mother and notchPoints are exchanged to fill the gap and continue to replicate after their proportion is getting lower and lower to damageChain dilution.Klenow fragment: a large fragment obtained from the hy
48、drolysis of Escherichia coli DNA-pol I by a special protease, with DNAFrom 3 to 5 and the polymerase activity of exonuclease activity, is a tool used in the research of molecular biology enzyme.Reverse transcription: using single stranded RNA as template and dNTP as raw material, double stranded DNA was synthesized under r