BEN 410
04/25/2003
Lecture Schedule
04/15: Read 2.1 to 2.5
04/17: 2.2.1 to 2.2.6
04/20: Quiz
04/22: Lecture
04/25: Read 2.1.6
Work done by a non-covalent force:
ΔL=∫
x
1
x
2
F(x)dx
F(x) = position of binding between two bases (distance b/w two bases)
∫
x
1
x
2
F(x)dx = area under the force curve
Typical numbers:
Energy per base pair = -10 kcal/mol
Number of base pairs = 5000
Total energy = -10 kcal/mol * 5000 = -50,000 kcal
Concepts:
Self-assembly: Molecules can self-assemble into complex structures.
Non-covalent interactions: These are forces that hold molecules together without forming covalent bonds.
Micelles: Spherical structures formed by amphiphilic molecules.
Bilayers: Sheet-like structures formed by amphiphilic molecules.
Questions:
What forces contribute to the structural stability of micelles and bilayers?
Critical micelle concentration (CMC)?
Compelling forces:
Attractive: Hydrophobic tails
Repulsive: Hydrophilic heads
CMC:
Qualitatively, as hydrophobicity increases, CMC decreases.
Examples:
1 head, 1 tail: CMC = 1 mM
1 head, 2 tails: CMC = 10 mM