MCB 2050 Study Guide - Final Guide: Mitochondrial Fission, Mitochondrial Fusion, Integral Membrane Protein

• School: University of Guelph
• Department: Molecular and Cellular Biology
• Course: MCB 2050
• Professor: John Vessey

Document Summary

Topic 6: mitochondria (chapter 1: 27-28, chapter 5: 178-182) Mitochondria morphology: double-membrane-bound organelle, outer and inner membranes differ functionally and in their overall protein and lipid composition. Outer membrane permeable to ions and small molecules: contains porins: (cid:1684)barrel-shaped(cid:1685) integral membrane proteins with large internal channel. Inner membrane lies adjacent to outer membrane and forms (cid:1684)folds(cid:1685) (cristae) that extend into the organelle(cid:1685)s interior (folds provide increased surface area) impermeable intermembrane space high [h+]; maintains h+ gradient, site of atp synthase. Step 2: at the surface of the mitochondrion, the matrix-protein(cid:1685)s n-terminal pre-sequence is recognized by the tom complex, translocase of the mitochondrial outer membrane, multi-protein complex consisting of a number of integral (outer) membrane proteins. Channel: barrel-shaped; mediates protein translocation across the outer membrane. Accessory proteins: serve as a (cid:1688)scaffold(cid:1689) to mediate protein transfer from the receptor to the channel: pre-sequence is bound by tom receptor.