Lecture 8 - Protein Folding III Flashcards Preview

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Flashcards in Lecture 8 - Protein Folding III Deck (19):
1

Describe the type of 2* structure associated with aggregated proteins?

Beta-sheets with cross linkage between them

2

______ are proteins that consist of cross-linked beta sheets

Aggregates

3

What are some possible causes of protein mis-folding/beta-sheet production?

Environmental damage/radiation/chemicals, etc.

4

Outline the steps that form the amyloid plaque

Lack of chaperones -> "seeding" or "nucleation"
Nuclei begin to form fibrils ("stringlike" with beta-cross links)
Begin to form "deposits"

5

Protein aggregation is characterized by formation of ______.

insoluble amyloid fibrils

6

Amyloid fibrils are derived from what naturally occurring cell protein?

amyloid precursor proteins (APP)

7

How are mis-folded proteins "marked" for degredation?

Through conjugation with uqiquitin, which marks it for removal by the proteosome.

8

Destroys damaged organelles (normal function) or other mis-folded proteins (when then proteosome is saturated)

authphagosome

9

Aside from seed polymerization, what other ways are proteins subject to aggregation?

Oxidative modification; phosphorylation; Ubiquitin like-SUMOylation; proteolytic cleavage

10

(Large/small) protein aggregates are believed to be responsible for cellular damage in neurodegenerative disease.

small

11

These contain a pocket that binds a metal ion; they then add the correct metal to proteins

metallochaperone

12

What are the three main types of storage/transport metalloproteins?

e- carriers
metal managers
oxygen managers

13

What are the three main types of enzymatic metalloproteins?

Hydroxylases
Oxidoreductases
Isomerases/synthases

14

What is the structure of most "normal" proteins?

alpha-helix

15

3 chars of infectious proteins

- aggregates of a specific protein that is transmissible
- proteins are resistant to dissolving
- completely/largely derived from naturally occurring cell proteins

16

Describe the characteristics of the "amorphorous aggregates" and why they are important to understanding disease.

Amorphorous aggregates have LESS E* and are MORE thermodynamically stable than native proteins; this causes them to "feed" into the pathway that produces amyloid fibrils

17

The lack of what normal cellular mechanism is thought to promote "seeding" or "nucleation" of pro-amyloid fibril type protein structures

A lack of chaperone correction

18

Zn, Pb, and Cd can all lead to _____ of protein folding

inhibition (heavy metal poisoning)

19

Metal ions are required for the correct folding of almost ____ of all proteins.

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