Term
| Enzymes stabilize the transition state relative to the ground state what does this cause? |
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Definition
| A decrease in activation energy which is resoponsible for the rate acceleration that results. |
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Term
| Mechanisms of an enzyme catalysis: |
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Definition
| approximation, covalent catalysis, general acid-base, electrostatic catalysis, desolvation and strain or distortion |
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Term
| First mechanism of an enzyme: approximation |
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Definition
| is the rate enhancement by proximity, that is the enzyme serves as a template to bind a substrate so that it is close to reactive groups of the enzyme. This results in a loss of rotational and translational entropies of the substrate upon binding to the enzyme. In addition, this reaction is now first order |
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Term
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Definition
| the concentration of the reactant required to cause the intermolecular reaction to proceed at the observed rate of the intramolecular reaction. |
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Term
| How is effective molarity calculated? |
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Definition
| By dividing the first order rate constant for the intramolecular reaction by the second order rate constant corresponding to intermolecular reaction |
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Term
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Definition
| some enzymes use nucleophilic AA side chains or cofactors in the active site to form covalent bonds with substrates, this makes a bond as a result of attack of an enzyme nucleophile at an electrophilic site of the substrate. (this nucleophile can be threonine, histidine, lysine, aspartate, cysteine) |
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Term
| specific acid/base catalysis |
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Definition
| catalysis occurs by H3O+ or OH- and is determined only by pH, NOT the buffer concentration |
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Term
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Definition
| occurs when acids other than H3O+ accelerate the reaction rate |
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Term
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Definition
| stabilization of the transition state may involve presence of an ionic charge or partial ionic charge at the active site to interact with opposite charge developing on the substrate at the transition state of the reaction |
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Term
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Definition
| an enzyme active site, which is largely or completely devoid of water, can mimic the reaction environment found in the gas phase, when the substrate enters the active site, water molecules are removed from polar or charged groups on the reactants which can result in ground state destabilization. |
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Term
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Definition
| enzyme need not necessarily exist in the appropriate conformation required to bind the substrate, substrate approaches the enzyme, various groups on the substrate interact with particular active site groups, which induces a conformational change in the active site of the enzyme. |
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Term
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Definition
| any organic molecule or metal ion that is essential for the catalytic action of the enzyme. |
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Term
| PLP in active site major interaction |
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Definition
| covalently bonded to lysine |
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Term
| The bond that breaks for the imine product must what |
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Definition
| the ch bond is the one perpendicular to the plane of pi system, (parallel with p orbitals) which has maximum pi overlap and minimizes the transition state energy for bond breakage of CH bond. |
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Term
| Name four reactions that PLP dependent enzymes can do. |
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Definition
| racemization, decaarboxylation, transamination, alpha cleavage |
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Term
| Is decarboxylation reversible or irreversible? |
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Definition
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Term
| Aminotransferases involve |
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Definition
| two substartes going to two products in two half reactions |
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Term
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Definition
| Mother's nature's sodium borohydride |
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Term
| Tetrahydrofolate is not the full coenzyme,,, what is? |
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Definition
| contains an additional carbon, between N5 and N10 positions which is transferred to other molecules. |
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Term
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Definition
| enzymes that utilize electron transfer protiens, such as ubiquinone |
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Term
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Definition
| One of the sulfonamides, the sulfa-related antibiotics which are used to treat bacterial and some fungal infections. |
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Term
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Definition
| a compound that disrupts metabolic processes, typically by blocking or acting as an alternative substrate for an enzyme in a metabolic pathway. |
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Term
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Definition
| reactive compound that has a structure similar to that of the substrate for a target enzyme, usually by acylation or alkylation mechanisms, thereby forming a stable covalent bond to the enzyme. |
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Term
| Quiescent affinity labeling |
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Definition
| inactivator reactivity is so low that reactions with nucleophiles in solution at physiological pH and temperature are exceedingly slow or nonexistent, but it will work with enzymes with exceptional nucleophilicity of groups using covalent catalysis. |
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