Proteins Intro

Question 1

What type of bonds are found in alpha helices

Answer 1

internal H bonds

Question 2

What groups are unfavoroable in alpha helices and why?

Answer 2

Large R groups and charged R groups:
steric hindrance and charge repulsion

Question 3

What is the setup of H bonds in alpha helics

Answer 3

every carbonyl Oxygen makes an H bond w an amide hydrogen 4 residues apart

Question 4

What type of bonds are found in B helices

Answer 4

interchain Hydrogen bonds

Question 5

How are R groups oriented in alpha helices

Answer 5

outward

Question 6

how are R groups oriented in beta sheets

Answer 6

perpendicular to the sheet

Question 7

What amino acids are commonly found in Beta sheet turns and why

Answer 7

proline and glycine: small shape allows bends

Question 8

Are improperly folded proteins typically insoluble or soluble

Answer 8

insoluble

Question 9

What is the protein-opathy in alzheimers

Answer 9

amyloid aggregation

Question 10

What is the most abundant protein in the body

Answer 10

collagen

Question 11

Type 1 colagen is found

Answer 11

bone, skin, tendon

Question 12

Type 2 collagen is found

Answer 12

cartilage

Question 13

Type 3 cartilage is found

Answer 13

skin, blood vessels, reticulin

Question 14

Type 4 collagen is found

Answer 14

basement membrane

Question 15

type 5 collagen is found

Answer 15

fibrils

Question 16

What are the 6 steps of collagen formation

Answer 16

1. synthesis
2. Hydroxylation
3. glycosylation
4. Exocytosis
5. proteolytic processing
6. cross linking

Question 17

What is collagen synthesized from

Answer 17

preprocollagen (translated from mRNA)

Question 18

What is the repeating subunit of collagen?

Answer 18

Glycinie - X - Y
where X or Y is proline or lysine

Question 19

What happens during hydroxylation stage of collagen synthesis

Answer 19

proline or lysine is hydroxylated

Question 20

What happens during glycosylation stage of collagen synthesis

Answer 20

proline or lysine is glycosylated
- procollagen triple helix forms

Question 21

What happens during proteolytic processing stage of collagen synthesis

Answer 21

Terminal ends of procollagen triple helix are cleaved
- insoluble Tropocollagen is formed

Question 22

What happens during cross linking stage of collagen synthesis

Answer 22

collagen fibrils are formed by covalent lysine-hydroxylysine cross linking

Question 23

What causes osteogenesis imperfecta?

Answer 23

inability to form procollagen triple helix during glycosylation step

Question 24

What causes scurvy?

Answer 24

vitamin C deficiency

Question 25

what step of collagen synthesis utilizes vitamin C?

Answer 25

2. hydroxylation

Question 26

What causes Ehlers-Danlos Syndrome VI?

Answer 26

inability to cross link procollagen during cross linking step

Question 27

What type of collagen is affected in the vascular type of Ehlers-Danlos?

Answer 27

Type 3

Question 28

What type of collagen is affected in the classic type of ehler's-danlos?

Answer 28

type 5

Question 29

What type of collagen is decreased in Osteogenesis imperfecta?

Answer 29

Type 1 coollagen

Question 30

What are the hemoglobin monomer chains?

Answer 30

alpha beta gamma delta

Question 31

what are the hemoglobin tetramers

Answer 31

A (adult) F (fetal) S (sickle) C (C-diseased)

Question 32

A qualitative hemoglobin abnormality is caused by ______ and affects ______

Answer 32

caused by amino acid susstitution affects type of hemoglobin

Question 33

A quantitative hemoglobin abnormality is caused by ______ and affects ________

Answer 33

caused by reduced gene expression affects how much hemoglobin is made

Question 34

What is the common mutation that leads to sickle cell hemoglobin

Answer 34

Glu 6 Val

Question 35

What is the mutation in hemoglobin C disease

Answer 35

Glu 6 Lys

Question 36

What is thalassemia?

Answer 36

Hemoglobin synthesis disorder w absence or reduced production of globin chains, leading to imbalanced globin synthesis

Question 37

Is thalassemia a quantitative or qualitative Hb disorder

Answer 37

Quantitative (it affects amount of Hb made)

Question 38

Alpha thalassemia involves

Answer 38

no alpha chains being produced, or reduced number of alpha chains

Question 39

Beta thalassemia involves

Answer 39

no Beta chains being produced or reduced number of beta chains

Question 40

What is the results of alpha or beta thalassemia

Answer 40

aggregates of the remaining chain units for ex.) in beta thalassemia, alpha chain aggregates form

Question 41

Main lethal effects of beta thalassemia

Answer 41

no erythropoiesis RBC death eroded bone

Question 42

What aggregates typically form in fetal alpha thalassemia? Are the soluble or insoluble?

Answer 42

Gamma aggregates, which are soluble

Question 43

What is the problem with the aggregates formed in alpha thalassemia?

Answer 43

Gamma aggregates bind oxygen VERY tightly, not releasing to fetal tissue

Question 44

Hydrops fetalis

Answer 44

fatal result of alpha thalassemia in fetus

Question 45

What are the tetramer aggregates formed in adult alpha thalassemia?

Answer 45

Beta tetramers (no gamma made anymore)

Question 46

Hb Bart's

Answer 46

gamma tetramers resulting from alpha thalassemia