BCH210H1 Lecture 5: Lecture 5- Fibrous and Globular Proteins; Membrane Proteins

• School: UTSG
• Department: Biochemistry
• Course: BCH210H1
• Professor: Reinhart Reithmeier

Document Summary

G-actin subunits combine to form f actin (filament: g actin subunits: single protein, forms globular structure (f actin, quarternary, assembly from g-actin f-actin requires atp. Side chain usually important: used for catalyzing the reaction (part of active site) Many diseases affect side chains no function. Contains heme group binds & stores o2 in muscles (until used) Found in high amounts in aquatic animals (ex. whales) Histidine side chains bind the iron (side chain = function) Forms disulphide bonds (ie cysteine is present) Active site: his 12, his 119, lys 41: histidine is very important! (side chain = function) Histidine both proton donor & acceptor (proton transporter) Hydrolysis reaction uses water to undergo full reaction. Transporter (move substances into/out of the cell: ex. Phospholipid molecule: (+) choline head (-) phosphate group. Spontaneously forms the membrane (no atp required) Flipped inside out: water is in the core of the protein, hydrophobic regions on the edges (b/c it"s connected to the membrane)