Organic components of Saliva

Question 1

Does parotid have higher protein secretions. than sublingual ?

Answer 1

Yes

Question 2

Is protein saliva content lower than found in plasma?

Answer 2

yes

Question 3

What are saliva protein properties?

Answer 3

• Lubrication
• Antimicrobial
• Enzymes

Question 4

What are salivary mucins?

Answer 4

glycoproteins that contain 0- & N- linked sugars

Question 5

What are O-linkages?

Answer 5

O-acetylgalactosamine

Question 6

What are N-linkages?

Answer 6

N-acetylglucosamine

Question 7

What do O linked sugars attach to?

Answer 7

serine and threonine amino acids

Question 8

What do N linked sugars attach to?

Answer 8

Asparagine amino acid

Question 9

what are carbohydrates attached in N-type linkage?

Answer 9

OLIGOSACCHARIDES

Question 10

What does attachment of Sialic acid on salivary mucins do?

Answer 10

confer negative charge so extend structure of protein

- repulsion between charges between folds in chain

Question 11

How are mucin oligomers formed?

Answer 11

cysteine residue form covalent cross links vis -SH group

Question 12

What are 2 types of mucin secreted by saliva?

Answer 12

MG1- High molecular weight mucin

MG2-Low molecular weight mucin

Question 13

What does MG1 do?

Answer 13

form complexes w/ salivary proteins

Question 14

What does MG2 do?

Answer 14

bind to oral streptococci

Question 15

What are salivary proteins?

Answer 15

Amylase
Proline rich proteins
Statherin
Histatins

Question 16

What salivary mucins do ?

Answer 16

• lubrication
• speech/swallow
• barrier to harmful microbes
• bind to teeth

Question 17

What is Statherin?

Answer 17

small protein that inhibits calcification of HAP

Question 18

What does high conc. of mineral ions mean?

Answer 18

calculus (calcified tar/plaque)

Question 19

what can calculus lead to?

Answer 19

blocked salivary duct

periodontal disease

Question 20

How does statherin work?

Answer 20

Bind to HAP so HAP cant bind to Ca

Question 21

What produces statherin?

Answer 21

acinar cells

Question 22

What are Proline rich proteins?

Answer 22

reduces HAP growth and is component of pellicle

Question 23

What mainly secretes PRPs?

Answer 23

Submandibular secretion

Question 24

What do PRPs prevent?

Answer 24

pathogens by binding to mineral to stimulate harmless microorg. colonisation instead of pathogens

Question 25

What do statherins and PRPs role in?

Answer 25

unwanted mineral deposition and growth

Question 26

What are Histatins?

Answer 26

defence peptides rich in Histidine amino acid

Question 27

Why do histatins have a buffering capacity?

Answer 27

pKa of side chains= neutral

Question 28

What are functions of Histatins?

Answer 28

- Active against S.Mutans (caries) - Bind to Ca so no calcification of HAP - on pellicle

Question 29

What are immunoglobins?

Answer 29

proteins for body defence against pathogens

Question 30

What is main Immunoglobin in saliva?

Answer 30

SigA,

Question 31

What is SigA

Answer 31

IgA differentiates via secretory component

Question 32

What happens when Immunoglobins bind to antigens?

Answer 32

agglutination so easier for bacteria to be swallowed

Question 33

What is salivary amylase dependant on?

Answer 33

Calcium

Question 34

What is amylase activated by?

Answer 34

Chloride ions

Question 35

What gland secretes amylase?

Answer 35

Parotid

Question 36

What does amylase do?

Answer 36

digest Carb. via hydrolysis of 1,4 glycosidic bond to form maltose disaccharides

Question 37

What can't amylase break down?

Answer 37

sucrose or polysaccharides w/ other glycosidic links

Question 38

What is lysozyme?

Answer 38

Muramidase enzyme

Question 39

What is a muramidase enzyme?

Answer 39

originate from striated duct of salivary gland

Question 40

What does lysozyme do?

Answer 40

hydrolysis of 1,4 glycosidic bond between N-acetylmuramic and N-acetylglucosamine in bacteria cell wall

Question 41

What bacteria cells does lysozyme target?

Answer 41

Bacteria tagged with SigA

Question 42

What can lysozyme be found?

Answer 42

HAP and found in pellicle

Question 43

What does Salivary Peroxidase enzyme do?

Answer 43

catalyse H202 + thiocyanate to form antibacterial 0SCN-

Question 44

What does lactoferrin antibacterial protein do?

Answer 44

binds to Fe3+ so bacteria can't use

Question 45

What do Cystatins do?

Answer 45

inhibit bacterial proteases so protect soft tissue of mouth

Question 46

Where can cystatins be found?

Answer 46

Pellicle and Bound to HAP

Question 47

What are pH rising factors?

Answer 47

Urea | Tetrapeptide Sialin

Question 48

how do factors rise pH?

Answer 48

microorg. in plaque metabolise urea and sialin to produce ammonia so neutralise plaque acid