Enzymology

Question 1

Biochemical reaction that occur within cells are nearly all mediated by a class of proteins known as

Answer 1

Enzymes

Question 2

Catalysts of biological systems and possess extraordinary catalytic power

Answer 2

Enzymes

Question 3

Most enzyme have a high degree of specificity for

Answer 3

The substrates they catalyze

Question 4

Urea’s decomposition in the presence of the enzyme, Urease, occurs after about

Answer 4

1 minute

Question 5

Respond to various metabolic conditions by changing their catalytic activities

Answer 5

Regulatory enzymes

Question 6

Carried out by mixing the enzyme with the chemical (substrate) that it acts upon

Answer 6

Enzyme Assay

Question 7

The difference in the rate at which the product is formed with an enzyme and the rate at which the product is formed without the enzyme is a measure of the

Answer 7

Enzyme activity

Question 8

Dependent upon the amount of enzyme present

Answer 8

Enzyme activity

Question 9

Can be detected in semen, prostate fluid, and in blood (also in fresh plants)

Answer 9

Acid Phosphatase

Question 10

Found in the lysosomes of animal cells and in the storage vacuoles of plant cells

Answer 10

Acid Phosphatase

Question 11

Measure of enzyme purity

Answer 11

Enzyme’s specific activity

Question 12

Catalyzes the hydrolysis of phosphate esters of primary and secondary alcohols as well as phenols at acid pH

Answer 12

Acid Phosphatase

Question 13

Synthetic substrate not found within the cell

Answer 13

p-nitrophenylphosphate (pNPP)

Question 14

The substrate pNPP is

Answer 14

Colorless

Question 15

Hydrolysis of pNPP yields

Answer 15

p-nitrophenol (pNP)

Question 16

In basic solution yields a yellow anion that absorbs light at 410 nm

Answer 16

pNP

Question 17

Reaction mixture for enzyme assay

Answer 17

1 M acetate buffer (pH 5.7), 0.1 M MgCl2, 50 mM pNPP (substrate), Water

Question 18

Often added to dilute solutions of enzymes to avoid denaturing

Answer 18

BSA (Bovine Serum Albumin)

Question 19

Micromoles of product formed/ minute x mg enzyme

Answer 19

Specific activity

Question 20

Specific Activity Formula

Answer 20

( A410/ Molar Extinction Coefficient) X (0.005L/15 min) (10^6 micromol/mol) X (1/mg enzyme) X (1/1cm)

Question 21

Specific Activity Units

Answer 21

micromole / min X mg enzyme

Question 22

Amount of substrate consumed (aka amount of product formed)

Answer 22

(A410 / 1.88x10^4 L/mole X cm) X (0.005L) X (10^6 micromol/mol) X (1/1 cm)

Question 23

Amount of substrate consumed units

Answer 23

Micromoles of product formed

Question 24

Amount of substrate originally present

Answer 24

(50 mmol / 1000mL) X (0.05 mL) X (10^3 micromole/mmol)

Question 25

Percent substrate consumed =

Answer 25

(Amount of substrate consumed/ amount of original substrate) X 100

Question 26

Amount of substrate originally present units

Answer 26

micro moles of substrate in the tube

Question 27

Graph

Answer 27

X-axis = mg of Enzyme
Y-axis = Abs (nm)