Flashcards
Proteins
Cards in this deck (18)
- 1Charge of acidic AAnegative
- 2Charge of basic AAPositive
+ Hydrophilic - 3% proteins in cell>50% dry weight
- 41° structure bondPeptide bonds in ppt
- 52° structure functionSatisfies bonding requirements so it reacts, but doesn't overreact
- 6α helix structure/ bondsH bonding b/tw every 4th AA on ppt backbone (not side chains)
Often in transmembrane proteins: C terminus inside, N-terminus extracellular - 7β pleated sheet2 or more ppt side by side
Core of many globular proteins
Forms many H bonds= v. strong - 8Random coil2°, in between a helix and B pleated sheet
- 93° structure function (1)More globular and spherical shape (compact + stable)
Resolves bonding requirement so unwanted reactions don't occur
Hydrophobic collapse 1° priority - 103° bondsHydrophobic collapse
Van der Waals interactions
Ionic bonds
Disulfide bonds - 11Hydrophobic collapse (3)1st priority of 3° structure
H20 pushes non-polar/ hydrophobic groups together
causes/ secured by Van der Waals - 12Van der Waals interactions (2)3°
Interactions between non-polar AA
Caused by/ secures hydrophobic collapse - 13Disulphide Bridge (2)3°
STRONG
Covalent bond between R-SH and HS-R - 144° structure2 or more 3° proteins
SOMETIMES required for function
fixed by interxns between side chains
e.g. collagen (3 3°), hemoglobin (4 ppt) - 15Chaperonins function (3) and structureProteins: cap and hollow cylinder
protects from degradation
right enviro for folding
some check/ refold/ mark for destruction - 16DenaturationBreaks: H bonds, hydrophilic/phobic intrxn/ s=s bonds
(All but AA chain)
Reversible - 17HydrolysisH2O added
AA cleavage of 1° structure - 18Post-transcriptional modificationOnce 3° structure
Can turn on/off act. site
Phosphorylation most common
Information
- Description
- Biosci 107 (Cell Structure and Function) Flashcards on Proteins, created by Jess Who on 12/04/2015.
- Created by
- Jess Who
- Views
- 0
- Rating
More on Levels of protein structure