CHANNELING OF SUBSTRATES AND INTERMEDIATES IN
... phosphate synthetase, glutamine phosphoribosylpyrophosphate amidotransferase, and asparagine synthetase have revealed the relative locations of multiple active sites within these proteins. In all of these polyfunctional enzymes, a product formed from the catalytic reaction at one active site is a su ...
... phosphate synthetase, glutamine phosphoribosylpyrophosphate amidotransferase, and asparagine synthetase have revealed the relative locations of multiple active sites within these proteins. In all of these polyfunctional enzymes, a product formed from the catalytic reaction at one active site is a su ...
Chapter 4 The Study of Chemical Reactions
... The negative sign in the entropy term of the free-energy expression. The positive value of the entropy change indicating that the products have more freedom of motion than the reactants, makes a favorable (negative) contribution to Problem : ...
... The negative sign in the entropy term of the free-energy expression. The positive value of the entropy change indicating that the products have more freedom of motion than the reactants, makes a favorable (negative) contribution to Problem : ...
Enzymes - Not Just Food Anymore
... proper conditions such as a ph or temperature change to occur. When this happens, they become activated or "turned on," and are able to transfer energy at a very fast rate. The same properties that will activate enzymes will also destroy them. In particular, they are affected by temperature. If you ...
... proper conditions such as a ph or temperature change to occur. When this happens, they become activated or "turned on," and are able to transfer energy at a very fast rate. The same properties that will activate enzymes will also destroy them. In particular, they are affected by temperature. If you ...
Redox in Electrochemistry
... measure of the amount of current that can be generated from a voltaic cell to do work. Electric charge can flow between two points only when a difference in electrical potential energy exists between the two points. In an electrochemical cell, these two points are the two ___________________. The po ...
... measure of the amount of current that can be generated from a voltaic cell to do work. Electric charge can flow between two points only when a difference in electrical potential energy exists between the two points. In an electrochemical cell, these two points are the two ___________________. The po ...
Microwave initiated reactions: Pechmann coumarin synthesis
... The efficacy of our method was examined by conducting other synthetic reactions. For example, a mixture on several grams scale of p-aminophenol (4-hydroxyaniline), acetic anhydride and acetic acid at room temperature was placed in a domestic microwave oven (800 W) and the acetylation reaction was in ...
... The efficacy of our method was examined by conducting other synthetic reactions. For example, a mixture on several grams scale of p-aminophenol (4-hydroxyaniline), acetic anhydride and acetic acid at room temperature was placed in a domestic microwave oven (800 W) and the acetylation reaction was in ...
C3.1 The Periodic Table
... Use the appropriate units for energy (joules, kilojoules, kJ per mole, kJ per gram, or calories per gram) Explain how the energy change of a reaction in solution can be calculated from the measured temperature change in an insulated container, for example when solids react with water or for neutrali ...
... Use the appropriate units for energy (joules, kilojoules, kJ per mole, kJ per gram, or calories per gram) Explain how the energy change of a reaction in solution can be calculated from the measured temperature change in an insulated container, for example when solids react with water or for neutrali ...
Bromelain from pineapple stem Product Number B4882 Storage
... pGlu-Phe-Leu-p-nitroanilide (Product No. P 3169) is a chromogenic substrate for the assay of thiol proteinases such bromelain (also papain and ficin). Bromelain has a KM of 0.30 mM with this substrate. Initial rates of hydrolysis can be measured spectrophotometrically at 410 nm using the molar M ext ...
... pGlu-Phe-Leu-p-nitroanilide (Product No. P 3169) is a chromogenic substrate for the assay of thiol proteinases such bromelain (also papain and ficin). Bromelain has a KM of 0.30 mM with this substrate. Initial rates of hydrolysis can be measured spectrophotometrically at 410 nm using the molar M ext ...
Rate of Reaction
... At some time, we observe that the reaction 2 N2O5 (g) → 4 NO2 (g) + O2 (g) is forming NO2 at the rate of 0.0072 mol / L∙s. (a) What is the rate of change of [O2], ∆ [O2]/ ∆t in mol / L∙s? (b) What is the rate of change of [N2O5], ∆ [N2O5]/ ∆t in mol / L∙s? Plan We can use the mole ratios from the ba ...
... At some time, we observe that the reaction 2 N2O5 (g) → 4 NO2 (g) + O2 (g) is forming NO2 at the rate of 0.0072 mol / L∙s. (a) What is the rate of change of [O2], ∆ [O2]/ ∆t in mol / L∙s? (b) What is the rate of change of [N2O5], ∆ [N2O5]/ ∆t in mol / L∙s? Plan We can use the mole ratios from the ba ...
© Ravi Divakaran, 1 Mechanisms of Ester hydrolysis [Ref: Jerry
... Reaction of an acid with an alcohol in presence of traces of a mineral or Lewis acid to give an ester as product is called esterification. The reverse reaction, i.e., the splitting of an ester into the component acid and alcohol is known as ester hydrolysis. In principle, these reactions are reversi ...
... Reaction of an acid with an alcohol in presence of traces of a mineral or Lewis acid to give an ester as product is called esterification. The reverse reaction, i.e., the splitting of an ester into the component acid and alcohol is known as ester hydrolysis. In principle, these reactions are reversi ...
Introduction_to_Chemical_Reactions_2011
... decreases during endothermic reactions because the system absorbs energy. The H0rxn is positive because Hfinal is more than Hinitial. In other words, the system gained energy. (sign goes with the system) Endothermic chemical reactions are generally unfavorable but may occur only if they are accompa ...
... decreases during endothermic reactions because the system absorbs energy. The H0rxn is positive because Hfinal is more than Hinitial. In other words, the system gained energy. (sign goes with the system) Endothermic chemical reactions are generally unfavorable but may occur only if they are accompa ...
The Pepsin Story - Penn Arts and Sciences
... Pepsin is an enzyme belonging to the family of aspartic protease enzymes. All members of this class of enzymes have two aspartic acid residues within their structure that act as the active site. For the most part, this class of enzymes is active at acid pH. In the case of pepsin, the pH of optimal a ...
... Pepsin is an enzyme belonging to the family of aspartic protease enzymes. All members of this class of enzymes have two aspartic acid residues within their structure that act as the active site. For the most part, this class of enzymes is active at acid pH. In the case of pepsin, the pH of optimal a ...
Elements, Compounds and Mixtures Elements are the simplest type
... increase with increasing size. Covalent network substances (carbon in the form of diamond and graphite, silicon dioxide, silicon carbide) have high melting and boiling points because all the atoms are interlinked by strong covalent bonds which take a lot of energy to break. ...
... increase with increasing size. Covalent network substances (carbon in the form of diamond and graphite, silicon dioxide, silicon carbide) have high melting and boiling points because all the atoms are interlinked by strong covalent bonds which take a lot of energy to break. ...
Enzyme catalysis
Enzyme catalysis is the increase in the rate of a chemical reaction by the active site of a protein. The protein catalyst (enzyme) may be part of a multi-subunit complex, and/or may transiently or permanently associate with a Cofactor (e.g. adenosine triphosphate). Catalysis of biochemical reactions in the cell is vital due to the very low reaction rates of the uncatalysed reactions. A key driver of protein evolution is the optimization of such catalytic activities via protein dynamics.The mechanism of enzyme catalysis is similar in principle to other types of chemical catalysis. By providing an alternative reaction route the enzyme reduces the energy required to reach the highest energy transition state of the reaction. The reduction of activation energy (Ea) increases the amount of reactant molecules that achieve a sufficient level of energy, such that they reach the activation energy and form the product. As with other catalysts, the enzyme is not consumed during the reaction (as a substrate is) but is recycled such that a single enzyme performs many rounds of catalysis.