Download presentation
Presentation is loading. Please wait.
Published byJody Chapman Modified over 9 years ago
1
Proteomics BIOL 4900
2
Section 1 – Amino Acid Structure
4
Formation of Peptide bond H2OH2O
5
Section 2 – Polypeptide Diversity Insulin primary structure Primary Structure – linear sequence of amino acids in a polypeptide chain 20 100 = 1.27 x 10 130 possible combinations 9 x 10 78 atoms estimated in universe
7
Section 3 – Secondary Structure Resonance prevents bond rotation of peptide bond
9
Ramachandran Plot
10
Pitch = 5.4 Å Turn = 3.4 aa C=O forms H bond With N-H of n+4 residue
12
Anti parallelParallel
14
Helical Wheel
15
All problems at end of chapter except 6, 13, and 19
16
Section 4 – Tertiary Structure
17
X-ray Crystallography
18
NMR
21
Section 5 – Quaternary Structure
22
Section 6 – Protein Stability
23
Salt Bridges Metal Ions
24
Section 7 – Membrane Proteins
28
Section 8 - Glycoproteins
29
Sialic acids are important for glycoproteins and glycolipids; recognition site of Influenza Viruses
30
Sugar derivatives Should be able to draw
31
N-linked oligosaccharides
32
O-linked oligosaccharides
33
Glycoproteins Carbohydrates can account for up to 70% of a protein by mass Half of all mammalian proteins are glycosylated
34
Biological Activity Define protein structure – Usually on surface – limit conformation; stabilize fold Recognition – Glycoconjugates Lectins – identify specific oligosaccharides Selectins – attachment of leukocytes – Blood groups
35
Section 9 – Lipid Classification Functions of lipids – essential component of biological membranes – Hydrocarbon chains serve as energy – intra- and intercellular signaling
36
saturated polysaturated unsaturated ω-3 fatty acid Δ 9 double bond almost always cis even number of carbons 18:0 18:1cΔ9 18:2cΔ9, 12 18:2cΔ9, 12, 15
38
Glycerophospholipids
40
Lipid anchors for proteins prenylated fatty acylated glycosylphatidylinositol
41
Occurs at CXXY If Y = Ala, Met, Ser; farnesylated If Y = Leu; Geranylgeranylated Prenylation
42
Fatty acylated Can add myristic acid or palmitic acid Myristoylation is very stable – amide linkage between α-amino of N-terminal G and myristic acid Palmiyolation can be undone by palmitoyl thioesterases – involved in protein signaling
43
GPI-Anchored Proteins
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.