Lecture 40: Glycoproteins and Lysosomal Storage Diseases Flashcards Preview

MGM Exam 2 (C) > Lecture 40: Glycoproteins and Lysosomal Storage Diseases > Flashcards

Flashcards in Lecture 40: Glycoproteins and Lysosomal Storage Diseases Deck (21):
1

What enzymes are lysosomal storage diseases typically associated with?

They have a defect in HYDROLASE ENZYME which results in the accumulation of substrate in the lysosome.

2

What are lysosomes?

Lysosomes are organelles with degradative enzymes.

3

Which type of bond do lysosomal storage diseases typically have a failure to hydrolyze?

Glycosidic bond

4

What are glycoproteins?

Proteins that have oligosaccharide chains covalently attached to their polypeptide chains.

5

T/F Glycogen is a glycoprotein.

False. Glycogen is a proteoglycan because it has a polysaccharide chain attached.

6

Describe a common O-glycosidic link.

Link between N acetyl galactosamine and either serine/ threonine.

7

Which molecule has a different O-glycosidic link?

Collagen.

It has a link between galactose/ glucose and the hydroxyl group of hydroxylysine.

8

What are the two types of N-glycosidic links?

1. High mannose
2. Complex (contains more than mannose)

9

What is I cell disease?

It is a disease where lysosomal enzyme targeting signal-mannose 6 phosphate- does not get attached so fibroblasts are missing lysosomal enzymes.

10

List some characteristics of a glycosaminoglycan.

1. Core protein of proteoglycans are linked to it.
2. Consists of a long polysaccharide chain with repeating disaccharide motif.
3. Densely negatively charged (carboxyl and/or sulfate): polyanionic
4. Amino groups

11

What are hyaluronic acid, chondroitin sulfate, dermatan sulfate, heparan sulfate, heparin, and keratin sulfate?

They are glycosaminoglycans.

12

What kind of arrangement are proteoglycan monomers + hyalyonic acid +linker proteins in?

Bottle Brush Arrangment

13

Which molecule is the sulfate donor (usually) in vivo?

PAPS (phosphoadenosine phosphosulfate)

14

Which Chinese molecule caused fatalities as it was sold as a cheaper alternative to the anticoagulant heparin?

Hypersulfonated chondroitin sulfate

15

What are mucopolysaccharidoses?

They are a series of hereditary diseases resulting from mutations in genes coding for degradative enzymes acting on glycosaminoglycans

16

T/F Most MPS are X linked.

False. With the exception of Hunter Syndrome, they are all AUTOSOMAL RECESSIVE.

17

What is missing in Hurler Syndrome?

alpha- L- iduronidase deficiciency

18

What is special about Hunter Syndrome and what is lacking?

It is X-linked and iduronate sulfatase is lacking.

19

T/F: Sanfillipo Syndrome is a disease where you obtain the same symptoms for more than one mutation.

True.

20

Which is milder: Hunter or Hurler?

Hunter Syndrome.

21

Accumulation of _______ is particularly associated with mental retardation.

Dermatan sulfate