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Enzymes. Amino Acid Basic Structure Primary Structure.

Jan 18, 2018

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Leonard Lamb

Amino Acid Basic Structure
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Page 1: Enzymes. Amino Acid Basic Structure Primary Structure.

Enzymes

Page 2: Enzymes. Amino Acid Basic Structure Primary Structure.
Page 3: Enzymes. Amino Acid Basic Structure Primary Structure.

Amino Acid Basic Structure

Page 4: Enzymes. Amino Acid Basic Structure Primary Structure.
Page 5: Enzymes. Amino Acid Basic Structure Primary Structure.

Primary Structure

Page 6: Enzymes. Amino Acid Basic Structure Primary Structure.

Secondary Structure

Page 7: Enzymes. Amino Acid Basic Structure Primary Structure.

Tertiary Structure

Page 8: Enzymes. Amino Acid Basic Structure Primary Structure.

Quaternary Structure

Page 9: Enzymes. Amino Acid Basic Structure Primary Structure.
Page 10: Enzymes. Amino Acid Basic Structure Primary Structure.

Yeast

Page 11: Enzymes. Amino Acid Basic Structure Primary Structure.

Sucrase

Page 12: Enzymes. Amino Acid Basic Structure Primary Structure.

Human/Bacterial/Bacterial Mg

Page 13: Enzymes. Amino Acid Basic Structure Primary Structure.

Catalase- H2O2 -> O2 + H20

Page 14: Enzymes. Amino Acid Basic Structure Primary Structure.

Catalase Lab

• Intro:• What is catalase / function/structure • Structure of proteins• Overview of Lab- pH, Temperature, substrate• Organism used in Lab

• Problem- write as a class• Hypothesis- write as a class• Procedure- See Vernier Biology Manual- 6B

» Enzyme Action: Testing Catalase Activity

Page 15: Enzymes. Amino Acid Basic Structure Primary Structure.

HOW ENZYMES FUNCTION

• Enzymes speed up the cell’s chemical reactions by lowering energy barriers

Page 16: Enzymes. Amino Acid Basic Structure Primary Structure.

– For a chemical reaction to begin• Reactants must absorb some energy, called the

energy of activation

Figure 5.5A

EA barrier

Reactants

Products1 2E

nzym

e

Page 17: Enzymes. Amino Acid Basic Structure Primary Structure.

– A protein catalyst called an enzyme• Can decrease the energy of activation needed to

begin a reaction

Figure 5.5B

Reactants

EA withoutenzyme

EA withenzyme

Net changein energy

Products

Ene

rgy

Progress of the reaction

Page 18: Enzymes. Amino Acid Basic Structure Primary Structure.

• A specific enzyme catalyzes each cellular reaction– Enzymes have unique three-dimensional

shapes• That determine which chemical reactions occur in

a cell

Page 19: Enzymes. Amino Acid Basic Structure Primary Structure.

Figure 5.6

Enzyme(sucrase)Glucose

Fructose

Active site Substrate(sucrose)

H2O

1 Enzyme availablewith empty activesite

2 Substrate binds to enzyme with induced fit

4 Products arereleased

3 Substrate is converted to products

– The catalytic cycle of an enzyme

Page 20: Enzymes. Amino Acid Basic Structure Primary Structure.

• 5.7 The cellular environment affects enzyme activity– Temperature, salt concentration, and pH

influence enzyme activity– Some enzymes require nonprotein cofactors

• Such as metal ions or organic molecules called coenzymes

Page 21: Enzymes. Amino Acid Basic Structure Primary Structure.

• Enzyme inhibitors block enzyme action– Inhibitors interfere with an enzyme’s activity

Page 22: Enzymes. Amino Acid Basic Structure Primary Structure.

– A competitive inhibitor• Takes the place of a substrate in the active site

– A noncompetitive inhibitor• Alters an enzyme’s function by changing its shape

Figure 5.8

Substrate

Enzyme

Active site

Normal binding of substrate

Enzyme inhibition

Noncompetitiveinhibitor

Competitiveinhibitor