Proteins Flashcards
Oligopeptides
Polypeptides
Proteins
2-10
11-49
50 or more
Proteins arrangement
Head to tail
N terminus to C terminus
Primary structure is….held together by …
The…is …to the protein
Number and sequence of a minor acids in the polypeptide chain
Peptide bonds
Sequence of amino acids /specific
Collagen has which structure
None, it has a unique structure to it
Native proteins
Newly synthesised proteins ready to work after Golgi modification
Do fibrous proteins have a tertiary structure
Examples
No
Collagen, elastin, keratin
Many poly peptides n to c
Many n to c and c to n
Parallel
Antiparallel
A change in a single amino acid may cause
Profound physiological effects
2 main forms of 2ndry structure
A - helical>folding on its axis, stabilized with hydrogen bonds
B pleated sheets> extended chain hydrogen bonds
A-helical must have…..only
Has …..only
While b pleated sheets have…..and……and….
1 chain
Intra chain bonds
2-5 chains
Inter and intra chain bonds
R groups of amino acids……. In a-helix
Project outwards
Other forms of 2ndry structure
Loop regions
b bends
Disordered regions
Tertiary and quaternary
Folding into 3D shape, globular proteins only, all bonds
If more than 1 polypeptides enter quaternary structure as well
The bonds 6
Peptide> condensation between 2 amino acids
Van der waals>weak interactions
Disulfide> proteins with sulfur, 2 cysteine
Hydrogen>polar side group with water or other polar group
Ionic bonds>NH3+ and COO-
Hydrophobic interactions>non polar R groups
Hydrophobic interactions present
In the interior side of the protein