Lecture 3 BIO 344

Hydrophobic amino acids in green and yellow

Predicting transmembrane helices from the amino acid sequence

Secondary structure of protein

Examples of β-barrels

Detergent Micelle in Water

DVD clip 38

Structures of Two Commonly Used Detergents

Liposome for studying membrane properties

Membrane Proteins in Human Red Blood Cells

Most Membrane Proteins have Structural Functions

Freeze Fracture Electron Microscopy

Band 3 can be seen as intramembrane particles, more on P face than E face

DVD clip 41

Chapter 11

Membrane Transport of Small Molecules and the Electrical

Properties of Membranes

Molecule movement across lipid bilayer without proteins

Permeability across lipid bilayer

Carrier Proteins

Channel Proteins

Passive vs. Active Transport

Three Ways of Driving Active Transport

Electrochemical gradient vs. membrane potential

Can work additively or against each other

Three Ways of Driving Active Transport

Conformational Change in Carrier Protein mediates passive transport

Three Types of Carrier Mediated Transport

DVD Clip 43

Mechanism of Na+ - glucosecarrier

Binding of Na+ and glucose is cooperative

DVD Clip 44

Microvilli in the small intestine

Transcellular transport of glucose