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#‼️BIOCHEMISTRY - PLE TOPNOTCH 2020 > PROTEINS > Flashcards

Flashcards in PROTEINS Deck (86)
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1

Contains an INDOLE RING 

Tryptophan (W)

2

• The skin breaks and blisters as a result of minor trauma

• Dystrophic form is due to mutations affecting the structure of type VII collagen, which anchors the basal lamina to collagen fibrils in the dermis

EPIDERMOLYSIS BULLOSA

3

Contains Guanidino Group

Arginine (R)

4

  • Disorder characterized by an inherited (intrinsic) defect in the RBC membrane that renders the erythrocytes spheroidal, less deformable, and vulnerable to splenic sequestration and destruction
  • Multiple mutations have been described: ankyrin (most common), spectrin, band 4.1 and band 3​

HEREDITARY SPHEROCYTOSIS

5

• Hemoglobin variant that has a single amino acid substitution in the 6 th position of the β-globin chain, in which lysine is substituted for glutamate

• Patients homozygous for hemoglobin C present with mild hemolytic anemia

HEMOGLOBIN C DISEASE

6

• Partial double-bond character

• Rigid and planar

• Generally in the trans configuration

• Disrupted by hydrolysis through prolonged exposure to a strong acid or base at elevated temperatures

Peptide Bonds

7

• Brittle bone syndrome

• Mutation in collagen genes result to bones that easily bend and fracture

• Most common form is autosomal dominant with abnormal collagen type I

OSTEOGENESIS IMPERFECTA

  • Multiple fractures (need to rule out child abuse)
  • Blue sclerae 
  • Hearing loss
  • Dental imperfections

8

Uncharged POLAR AA

STCY QN

Serine (S), (Threonine (T), Cysteine (C), Tyrosine (Y), Glutamine (Q), Asparagine (N)

 

9

secondary structure is stabilized by what bond?

hydrogen bonding

10

attach the α-amino group of one amino to the α carbonyl group of another

Peptide bonds

11

z 2 ε 2 Hb

Embryonal hemoglobin (Hb Gower 1)

12

refers to carbon monoxide bound to hemoglobin

carbohyxhemoglobin

13

• Present in Lathyrus seeds

• Implicated in neurolathyrism, characterized by progressive and irreversible spastic paralysis of the lower extremities

Homoarginine and β-N-Oxalyldiaminopriopionic acid (β-ODAP)​

14

Basic AA

  • Proton acceptors

     

"BASIC HKR"

Histidine (H)

Lysine (K)

Arginine (R)

  • At neutral pH:

    • Arginine and lysine are positively charged 

    • Histidine, being a weak base, has no charge

15

• Genetic disorders affecting the structure of type IV collagen fibers, the major collagen found in the basement membranes of the renal glomeruli

ALPORT SYNDROME

  • Hematuria (main presenting sign)
  • Ocular lesions
  • Hearing loss
  • Patients may eventually develop end-stage renal disease

16

Collagen is rich in what AAs?

glycine and proline

17

Precursor of carnitine

LYSINE​

18

NON POLAR AA 

"GAVIL Pro MidWiFe"

  • Glycine (G)
  • Alanine (A) 
  • Valine (V)
  • Isoleucine (I)
  • Leucine (L)
  • Proline (P)
  • Methionine (M)
  • Tryptophan (W)
  • Phenylalanine (F) 

19

• Autosomal dominant connective tissue disorder

• Mutation in the fibrillin gene

MARFAN SYNDROME

  • Usually taller and thinner than family members
  • Dolichostenomelia
  • Arachnodactyly
  • Aortic dilatation (70 to 80%) and dissection
  • Upward dislocation of the lens (ectopia lentis)

20

Heme protein present in heart and skeletal muscle

MYOGLOBIN

21

• Not an amino, but an imino acid

• Contributes to the fibrous structure of collagen and interrupts αhelices in globular proteins

PROLINE​

22

Types of Collagen 

23

• Most common type of secondary structure 

• Spiral structure with polypeptide backbone core, with side chains extending outward

• 3.6 AA per turn

• Disrupted by proline, AAs with large or charged R-groups

Alpha Helix

• Examples:

o Keratin (100% α-helix)

o Hemoglobin (80% α-helix)

24

PHENYLALANINE / TYROSINE DERIVATIVES​

Pare, True Love Does Not Exist To Me

Phenylalanine →Tyrosine → L-dopa → Dopamine → Norepinephrine → Epinephrine

Tyroxine, Melanin 

25

R (relaxed) form: ____ oxygen affinity (300x)

high

26

The set of all the proteins expressed by an individual cell at a particular time

PROTEOME

*Unlike your genome which remains the same throughout life, your proteome changes all the time.

27

contains IMIDAZOLE RING 

Histidine (H)

28

  • Connective tissue protein with rubber-like properties, responsible for extensibility and elastic recoil in tissues
  • Found in tissues where elastic recoil is needed
    • lungs, large arteries, elastic ligaments, vocal cords, ligamentum flavum
  • Rich in proline and lysine, but contains little hydroxyproline and no hydroxylysine
  • Precursor tropoelastin is deposited into an irregular fibrillin scaffold cross-linked by desmosine

ELASTIN

29

  • Source of methyl groups in metabolism
    • Involved in transfer of methyl groups as S-adenosylmethionine (SAM)
  • Precursor of homocysteine and cysteine

METHIONINE

30

• Precursor of histamine

• Also used in the diagnosis of folic acid deficiency (FIGLU excretion test)

• Concentration in the brain hypothalamus varies in accordance with the circadian rhythm

Histidine