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| Enzymes are what and what size? | They are biological catalysts that are very large proteins |
| Enzymes are specific which means what? | They react with one or only a few types of molecules or substrates |
| At what rate do enzymes permit reactions of the body to go at? | Conditions the body can tolerate |
| How do you name an enzyme | You name what is reacts with and switch suffix to -ase |
| Oxidoreductase | Catalyze a redox reaction |
| Transferase | Transfers a functional group |
| Hydrolase | Cause hydrolysis reactions |
| Lyase | Break C-O. C-C, or C-N bonds |
| Isomerases | Rearrange functional groups |
| Ligase | Joins two molecules |
| What do emzymes change? | How a reaction will proceed |
| Changing how a reaction proceeds does what? | Reduces activation energy |
| Non-catalyzed reaction | Reaction rate increases with concentration |
| Catalyzed reactions | Increase but only to a certain point |
| Vmax | Maximum velocity (enzyme works as fast as possible) |
| Catalytic site | Where the reaction actually occurs |
| Binding site | Area that holds substrate in place |
| What bond is used to hold the substrate in place | Weak non-covalent bonds |
| Shape is complementary to the substrate and determines what? | The specifity of the enzyme |
| What are sites? | Pockets or clefts on the enzyme surface. |
| Steps in an enzymatic reaction | 1. enzyme and substrate combine to from a complex 2. complex goes through a transition state 3. a complex of the enzyme and the product is produced 4. the product and enzyme seperate 5. all of the steps are equlibria |
| enzyme + substrate | enzyme substrate complex |
| transition state | not a substrate or a product |
| lock and key model was developed by who and when? | Emil Fisher in 1890 |
| what does this model assume? | that an enzyme active site will only accept a specific substrate |
| in the induced fit model who was it produced by and when? | Daniel Koshland in 1958 |
| what does the induced fit model assume? | continuous changes in active site structure as a substrate binds |
| an absolutely specific enzyme | only react with a single substrate |
| a group specific enzyme | works with similar molecules with the same functional group |
| a linkage specific enzyme | catalyzes a specific combination of bonds |
| a stereochemically specific enzyme | only will work with the proper D or L form |
| Apoenzyme | the protein portion of the enzyme and almost ready to work |
| cofactor | the prosthetic group needed to activate the apoenzyme |
| apoenzyme + coenzyme | holoenzyme |
| coenzymes are responsible for doing what | transporting the substrate |
| exceeding normal Ph and temperature ranges does what to an enzyme reaction rate | reduces it |
| end product inhibition | an enzyme substrate reaction is an equilibrium / if product builds up the reaction slows |
| allosteric enzymes | the presence of an effector molecule alters how an enzyme will react |
| positive allosterism | activates the enzyme |
| negative allosterism | deactivates the enzyme |
| feedback inhibition | a type of allosteric effect where a product acts as the effector molecule |
| zymogens | inactive enzymes too large |
| proteolytic cleavage | a portion of the protein chain must be removed to make a zymogen active |
| inhibition studies provide what three things? | 1. info on metabolic pathways 2. insight on how drugs and toxins exert their effects 3. better understanding of enzyme reaction mechanisms |
| irreversible inhibitors | forms covalent or strong noncovalent bonds the site of the attack is an amino acid group |
| reversible inhibitors | forms weak, noncovalent bonds that readily dissociate from an enzyme |
| an enzyme is only inactive when what is present? | an inhibitor |
| competitive inhibitor | resembles the normal substrate and competes with it for the same site |
| noncompetitive inhibitors | materials that bind at a location other than the normal site- changes how the enzyme performs |
| chymotrypsin is what kind of enzyme? | a proteolytic |
| acetylcholinesterase is needed for what? | an enzyme needed to transmit a nerve signal at a neuromuscular junction |
| organofluorophosphates | binds to an enzyme causing death of it |
| succinylcholine | competes for sites on the muscle and is used as a muscle relaxant |
| blood clotting | formation of fibrin |
| extrinsic | activated by tissue damage outside blood vessels |
| intrinsic | activated by damage within blood vessels |
| heparin | an anticoagulant |
| antithrobin III | acts by acclerating the action of the existing inhibitor of thrombin |
| a family of enzymes | peroxidase |
| what do peroxidases' do? | they link the reduction of hydroperoxide to the oxidation of another species |
| you can test for peroxidases by adding what to the liver? | hydrogen peroxide |
| albinisms defective enzyme is | tyrosinase |
| galactosemia's defective enzyme is? | glactose |
| phenylketonuria's defective enzyme is | phenylalanine hydroxylase |
| Tay-Sachs diesase's defective enzyme is? | hexosaminidase |
| phenylketonuria | genetic defect that results in a defect of the enzyme phenylalanine hydroxylase |
| PKU results in | physical and mental development if untreated |
| Catalytic RNA | discovered by Sidney Altman and Thomas Cech |
| ribozyme | RNA enzymes |
| Ribonuclease P | present in all organisms |
| Rnase P functions by? | hydrolytic cleavage of the phosphodliester bond |
| hammerhead ribozymes | are found to be plant RNA viruses |
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