Enzyme (Quiz 1)

Question 1

are proteins that are catalysts of biochemical
reactions.
* Typically has a globular shape
* Complex 3-D structure

Answer 1

Enzyme

Question 2

____ they are Biological Catalysts

• Increase the rate of reaction by ____ of activation.
• Catalyze nearly ____ the chemical reactions taking place in the cells of the body.
• Have unique three-dimensional shapes that fit the shapes of ____.

Answer 2

• Enzyme
• lowering the energy of activation
• all
• reactants

Question 3

net energy released from splitting of lactose

Answer 3

activation energy without enzyme

Question 4

when chemical rxn’s activation energy decreased, net energy released

Answer 4

activation energy with enzyme

Question 5

in 1833 the first clear recognition of enzyme was made by these two people

Answer 5

Payen and Persoz

Question 6

an alcohol precipitate of malt extract contained in a thermolabile substance that converted strach into sugar.

Answer 6

diastase

Common name: alpha-amylase (a-amylase)

Question 7

he was the first to crystallize enzyme

Answer 7

J.B. Sumner (1924-1930)

Question 8

there are more than ____ biochemically important enzyme catalyzed reactions

Answer 8

2500

Question 9

they are characterized by specificity for substrates

Answer 9

enzyme

Question 10

they modulates an enzymes activity

Answer 10

effectors

Question 11

enumerate the different types of effectors

Answer 11

Activators, inhibitors, both, or depending on conditions

Question 12

its size could vary from small single unit to large multiple units

Answer 12

enzyme

Question 13

• Found in animal and plant cells
• Needed to speed up the breakdown of HYDROGEN PEROXIDE
• Breaks it down to OXYGEN and WATER

Answer 13

catalase

Question 14

• Found in saliva and in the pancreas
• Break down enzyme
• Breaks STARCH down to MALTOSE

Answer 14

amylase

Question 15

Synthesis enzyme (builds up)
* Builds Glucose-1-Phosphate molecules into Starch
* The formation of starch is tested using iodine solution

Answer 15

Potato Phosphorylase

Question 16

reaction of enzyme without substrate

Answer 16

no reaction

Question 17

enzyme + substrate

Reaction?

Answer 17

rxn: water + oxygen (bubbles)

Question 18

liver homogenation

Answer 18

catalase enzyme

Question 19

– high efficiency, 10³ to 10¹⁷ faster than the corresponding uncatalyzed reactions.

Answer 19

Catalytic Efficiency

Question 20

high specificity, interacting with one or a few specific substrates and catalyzing only one type of chemical reaction.

Answer 20

specificity

Question 21

what are the mild reaction conditions?

Answer 21

• 37°C,
• physiological pH,
• ambient atmospheric pressure.

Question 22

part of the enzyme where the reactants bind, and where the biochemical reaction occurs

Answer 22

active site

Question 23

• Amino acid side chains interact, metal ions,
• Various types of polar, non-polar, ionic interactions

Answer 23

enzyme active site

Question 24

• The ____ is a region within an enzyme that fits the shape of molecules called _____

Answer 24

active site
substrate

Question 25

* **____contains amino acid ____** **that align and bind the ____.** * **and it Releases products when the _____ is complete**

Answer 25

* active site * R group * substrate * reaction is complete

Question 26

the **substrate fit like a key** in a lock, the **active site is like a lock**.

Answer 26

lock and key model

Question 27

they are **small nonprotein molecules** (cofactors and prosthetic group)

Answer 27

subunits

Question 28

apoenzyme + nonprotein part

Answer 28

holoenzyme

Question 29

what are the *two* **chemical composition of enzyme**

Answer 29

(1) Single Protein (2) Conjugated Protein

Question 30

what are the *two* **types of cofactor**

Answer 30

coenzyme and prosthetic group

Question 31

the **protein portion, inactive** part of holoenzyme

Answer 31

apoenzyme

Question 32

it is the **nonprotein portion, activator** part of holoenzyme

Answer 32

cofactor

Question 33

they are **loosely bound to enzyme** (*non-covalently bound*)

Answer 33

coenzyme

Question 34

they are very **tightly or even covalently bound** to enzyme (covalently bound)

Answer 34

prosthetic group

Question 35

*forms* of **active enzyme with only protein**

Answer 35

simple enzyme

Question 36

**forms of active enzymes** that is formed by.. * protein and metal ion * protein and organic molecule (coenzyme)

Answer 36

Enzyme + cofactor

Question 37

An **additional** **non-protein molecule** that is needed by some enzymes to **help the reaction**

Answer 37

cofactors

Question 38

are t**ightly bound cofactors**

Answer 38

prosthetic groups

Question 39

* Cofactors that are **bound and released easily** are called ____ * Many vitamins are ___

Answer 39

coenzymes

Question 40

* Many active enzymes require a __ as cofactors * **Zn2+** cofactor for ___, **stabilizes** the ___ **during the _____ of a peptide bond**.

Answer 40

* Metal Ions * carboxypeptidase * carbonyl oxygen * hydrolysis

Question 41

* ___ **catalyze the same reaction** in different tissues in the body. * ________ , which **converts lactate to ___, (LDH)** consists of ____ .

Answer 41

* isoenzymes * lactate dehydrogenase * pyruvate * five (5) isoenzymes

Question 42

Classification of Enzyme * IUPAC * EC * Four integer EC number and a name * Common name: usually the **principal specific reactant + ___** (suffix) * Does **not follow any rule** (in naming) o ___ o ___

Answer 42

* *-ase* * pepsin * rhodanese

Question 43

**Naming Enzyme** * The **name** of an enzyme **identifies** the ____ substance, usually **ends with -ase** (*sucrase from sucrose*) * The name also **describes** the ____ of the enzyme (*oxidases*) * Sometimes **common names are used, particularly for** the ____ enzymes such as ***pepsin*** and ***trypsin*** * Some names **describe both** the ___ and the ___. (*alcohol dehydrogenase oxides ethanol*)

Answer 43

* **reacting** substance * **function** of the enzyme * **digestion enzymes** * **substrate** and **function**

Question 44

* catalyze **oxidation-reduction** reactions * used to convert L-Lactate (1 C bonded to O2) to Pyruvate (2 C bonded to O2) through Lactate dehydrogenase

Answer 44

oxidoreductases (dehydrogenases)

Question 45

* catalyze **group-transfer** reaction, transfer groups of atoms * transferred amino group through **alanine transaminase**

Answer 45

transferases

Question 46

* catalyze **hydrolysis** * used to convert pyrophosphate to phosphate (mechanism: water did chemistry to break a bond )

Answer 46

hydrolases

Question 47

* *addition/removal of a group to a double bonds* **without hydrolysis or oxidation**

Answer 47

lyases

Question 48

* catalyze **structural change** within a single molecule * **rearrangement** of atoms

Answer 48

isomerases

Question 49

___ **catalyze** **ligation** or ____ of two substrates, use ____ to combine molecules

Answer 49

* ligases * joining * **ATP** (Adenosine triphosphate)

Question 50

Enzymes are classified according to the type of reaction they catalyze

Answer 50

classification of enzyme

Question 51

Naming enzyme examples * _____ catalyzes the hydrolysis of sucrose * _____ catalyze oxidation reaction

Answer 51

* sucrase * oxidases

Question 52

He initiated the **use of -ase** in naming enzyme

Answer 52

Duclaux (1898)