IMMUNOSERO // STEVENS CHAP 5: ANTIBODY STRUCTURE AND FUNCTION

Question 1

Glycoproteins found in serum portion of blood

Answer 1

Immunoglobulins

Question 2

All immunoglobulins are composed of

Answer 2

86% to 98% Polypeptide
2% to 14% Carbohydrate

Question 3

Serum is placed on an _______ to separate out the proteins

Answer 3

agarose gel and an electrical current

Question 4

slowest moving proteins

Answer 4

Immunoglobulins

Question 5

Immunoglobulins appear in ______ band

Answer 5

gamma (γ) band

Question 6

Considered to be the main humoral element of the adaptive immune response.

Answer 6

Immunoglobulins

Question 7

Play an essential role in antigen recognition and in Biological activities related to the immune response such as opsonization and complement activation.

Answer 7

Immunoglobulins

Question 8

Immunoglobulins is Divided into 5 major classes on the basis of heavy chain

Answer 8

1. IgG - heavy chain γ
2. IgM - heavy chain μ
3. IgA - heavy chain α
4. IgD - heavy chain δ
5. IgE - heavy chain ε

Question 9

All immunoglobulin molecules are made up of a basic

Answer 9

fourchain tetrapeptide unit

Question 10

All immunoglobulin molecules are made up of a basic fourchain tetrapeptide unit that consists of:

Answer 10

2 large chains - called heavy or H chains
2 smaller chains- called light or L chains

Question 11

Heavy and light chains are held together by

Answer 11

1. Noncovalent forces and
2. Disulfide interchain bridges

Question 12

The basis structure ofimmunoglobulins are discovered by

Answer 12

Gerald Edelman and Rodney Porter

Question 13

the most abundant of all the antibodies.

Answer 13

IgG

Question 14

Centered on using analytic ultracentrifuge to separate out Igs on the basis of molecular weight.

Answer 14

EDELMAN’S WORK

Question 15

intact IgG molecules: had a sedimentation

Answer 15

coefficient of 7 S

Question 16

indicates the sedimentation rate in an analytical ultracentrifuge.

Answer 16

Svedberg unit [S]

Question 17

On obtaining a purified preparation of IgG, Edelman used _____ to unfold the molecule

Answer 17

7M urea

Question 18

Once unfolded, exposed sulfhydryl bonds could bebroken by a reducing agent such as

Answer 18

mercaptoethanol

Question 19

Molecular weight of approx. 50,000
Designated as the H chain

Answer 19

3.5 S fraction

Question 20

Molecular weight of 22,000
Designated as the L chain

Answer 20

2.2 S fraction

Question 21

used to cleave IgG into 3 pieces of about equal size, each having a sedimentation coefficient of 3.5
S and representing a molecular weight of approximately 45,000 to 50,000 d.

Answer 21

Papain

Question 22

Carboxymethyl Cellulose Ion Exchange Chromatography separated this material into 2 types of fragments:

Answer 22

Fc fragment
Fab fragment

Question 23

fragment crystallizable

Answer 23

Fc fragment

Question 24

fragment antigen binding

Answer 24

Fab fragment

Question 25

Spontaneously crystallized at 4°C; No antigen-binding ability

Answer 25

Fc fragment

Question 26

for opsonization and complement fixation.

Answer 26

Fc fragment

Question 27

Now known to represent the carboxy-terminal

Answer 27

Fc fragment

Question 28

Consists of:
1⁄2 of two H chains that are held together by S–S bonding.

Answer 28

Fc fragment

Question 29

Have antigen-binding capacity; one antigen-binding site (2 per Ab)

Answer 29

Fab fragment

Question 30

Consists of:
1 L chain and
1/2 of an H chain held together by disulfide bonding.

Answer 30

Fab fragment

Question 31

Uses papain

Answer 31

PORTER’S WORK

Question 32

Used pepsin to obtain additional evidence for the structure of immunoglobulins.

Answer 32

ALFRED NISONOFF

Question 33

Cleave IgG at the carboxy-terminal side of the interchain disulfide bonds, yielding One single fragment with a mol. weight of 100,000 d and ALL the antigen-binding ability, known as F(ab’)2

Answer 33

Pepsin

Question 34

An additional fragment called _______ was similar to FC except that it disintegrated into several smaller pieces.

Answer 34

FC’

Question 35

was bonded to an H chain by means of an S–S bond

Answer 35

L chain

Question 36

were joined to each other by one or more S–S bonds

Answer 36

H chain

Question 37

Amino-terminal end

Answer 37

Variable region

Question 38

Carboxy- terminal end

Answer 38

One or more constant region

Question 39

Found in urine of patients with multiple myeloma

Answer 39

Bence Jones proteins

Question 40

L chains that were being secreted by the malignant plasma cells

Answer 40

Bence Jones proteins

Question 41

The bench jones proteins when heated to 60°C

Answer 41

Precipitate from urine

Question 42

The bence jones proteins when further heated to 80°C they;

Answer 42

Redissolve

Question 43

2 MAIN TYPES OF L CHAIN

Answer 43

Kappa (κ) chains
Lambda (λ) chains

Question 44

60% of L chains

Answer 44

Kappa (κ) chains

Question 45

Each contained between 200 and 220 amino acids; from position number 111 onward (the amino terminus is position number 1), it was discovered that each type had essentially the same sequence. This region was called the

Answer 45

constant region

Question 46

Demonstrates presence of domains similar to those in L chains—that is, variable and constant regions.

Answer 46

HEAVY-CHAIN SEQUENCING

Question 47

Constant regions of the H chain: Unique to each class and give each immunoglobulin type its name

Answer 47

Isotype

Question 48

A unique amino acid sequence that is common to all Ig of a given class in a given species.

Answer 48

Isotype

Question 49

Minor variations of these sequences that are present in some individuals but not others

Answer 49

Allotypes

Question 50

Occur in the four IgG subclasses, in one IgA subclass, and in the κ L chain.

Answer 50

Allotypes

Question 51

These genetic markers are found in the constant region and are inherited in simple Mendelian fashion.

Answer 51

Allotypes

Question 52

Some of the best-known examples of allotypes are variations of the γ chain known as

Answer 52

G1m3 and G1m17.

Question 53

Variable portions of each chain are unique to a specific Ab

Answer 53

Idiotype

Question 54

The amino-terminal ends of both L and H chains contain these regions, which are essential to the formation of the antigen-binding site.

Answer 54

Idiotype

Question 55

The a mino-terminal ends of both L and H chains contain these regions, which are essential to the formation of the antigen-binding site.

Answer 55

Idiotype

Question 56

The segment of H chain located between the CH1 and CH2 regions

Answer 56

HINGE REGION

Question 57

It has a high content of proline and hydrophobic residues

Answer 57

HINGE REGION

Question 58

Chains that do not have hinge region

Answer 58

Mu and Epsilon chains