1 ENZYMES Enzymes 2 Enzymes are protein molecules

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1 ENZYMES

1 ENZYMES

Enzymes 2 Enzymes are protein molecules that speed up the chemical reactions of organisms.

Enzymes 2 Enzymes are protein molecules that speed up the chemical reactions of organisms. Without enzymes, most of the reactions in a cell would proceed slowly to maintain life. Reactants are converted into products faster than they would be without the enzyme Enzymes remain undamaged, ready to catalyze another reaction

Activation Energy 3 Activation Energy – is the energy required for a chemical reaction

Activation Energy 3 Activation Energy – is the energy required for a chemical reaction to occur. Enzymes speed up reactions by lowering the activation energy needed to start a reaction.

Activation Energy – con’t 4 Most common source of activation energy is HEAT. Will

Activation Energy – con’t 4 Most common source of activation energy is HEAT. Will increase the speed of most reactions. However, proteins are denatured at high temperatures and lose their function.

Activation Energy – con’t 5 Names of enzymes usually end in “-ase” Thus, amylase

Activation Energy – con’t 5 Names of enzymes usually end in “-ase” Thus, amylase catalyzes the breakdown of amylose into maltose subunits, and maltase catalyzes the breakdown of maltose into individual glucose molecules.

Enzyme Activity 6 To catalyze a reaction, an enzyme attaches to the reactants A

Enzyme Activity 6 To catalyze a reaction, an enzyme attaches to the reactants A substrate is the reactants that an enzyme acts on when its catalyzes a chemical reaction. Substrates bind to a small portion of the enzyme called the active site. Usually a pocket or groove in the 3 -D structure of the protein

Enzyme Activity – con’t 7 Enzymes are very specific for the types of substrates

Enzyme Activity – con’t 7 Enzymes are very specific for the types of substrates they attach. They will only bind to one type of molecule Different enzymes needed for every reaction

Enzyme Activity – con’t 8 Induced fit model is a model of enzyme activity

Enzyme Activity – con’t 8 Induced fit model is a model of enzyme activity that describes an enzyme as a protein molecule that changes shape to better accommodate the substrate Enzyme-Substrate Complex is an enzyme with its substrate attached to the active site

9 Enzyme Activity and the Environment Temperature and p. H have an effect on

9 Enzyme Activity and the Environment Temperature and p. H have an effect on an enzyme’s activity. Temperature Increase in temp = increase in reaction speed However, as the temp increases beyond a point proteins begin to denature Every enzyme has an optimal temp

Enzyme/Environment – con’t 10 Most human enzymes work best around 37ºC Enzymes also have

Enzyme/Environment – con’t 10 Most human enzymes work best around 37ºC Enzymes also have optimal p. H Pepsin – p. H 2 – stomach Trypsin – p. H 8 – small intestine

Industrial Uses of Enzymes 11

Industrial Uses of Enzymes 11