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Flashcards in Proteins Deck (32):
1

What are 3 examples of proteins?

Enzymes
Structural Proteins
Transport Proteins

2

What is an enzyme-like function?

Amelogenin acting as a scaffold for the mineralization of enamel

3

What is the typical composition of bone?

Mineral (Hydroxyapatite 50-70%)
Protein (Mostly collagen; 20-40%)
Non-collagen proteins (typically 1-2%)
Lipids (3%)
Water (5-10%)

4

The linkage between amino acids in protein is an _____ linkage?

amide

5

Two amino acids hooked together is a ______ bond

Peptide

6

Most proteins are ___ - ______ amino acids long

50 - 2000

7

Each protein sequence produces its own _______

Function

8

Omega

specifies protein backbone dihedral angle

9

Rotation around the peptide bond is restricted by ________. This simplifies deducing secondary structures.

Resonance

10

Alpha helices

Spiral staircases with amino acid steps

11

How many steps per alpha helice turn?

3.6 steps

12

What handed are alpha-helices?

right-handed

13

How do side chains project on alpha helices?

up and out

14

What is the distance between

0.15 nm

15

What is the distance between neighboring B strand residues?

0.35 nm

16

How do beta strands pair?

donor-acceptor backbone

17

B-strands are fully ______ conformations

extended

18

B - strands can align both _______ and ______ to form B- sheets

parallel
antiparallel

19

Silk fibroin is all __ sheet

Beta

20

Amyloid of _______ disease is almost all __ sheet

Alzheimer
Beta

21

__ - keratin (intracellular fibers of skin) is all __ helix (coiled-coil)

alpha
alpha

22

Myosin (protein for muscle contraction) is mostly __ helix

alpha

23

Some _______ - forming proteins are disordered before forming amyloid

amyloid

24

Amyloid

starch like but is actually a protein, presence in almost all neurogenerative diseases

25

Parallel B-sheet can wrap as a helix __ - helix

Beta

26

The collagen triple helix is 1/3 _____.

Glycine

27

The collagen triple helix has inter-helical -bonds

H

28

What is the hydrogen bond donor of the collagen triple helix?

NH2 of glycine

29

What is the three dimensional structure of the polypeptide chain stabilized by?

hydrogen bonds, electrostatic and hydrophobic interactions and certain cases by disulfide linkage between cysteine residues

30

Quaternary structure

refers to the arrangement of protein subunits in a multinumeric complex

31

What is one of the most well known and highly characterized multi-protein complexes?

Hemoglobin heterotetramer

32

The partial double bond character of the peptide bond restricts neighboring groups to a single ______.

plane