BIOB10H3 Lecture Notes - Lecture 12: Mitochondrion, Intermembrane Space, Alpha Helix
Document Summary
Mitochondria have an inner and outer membrane (double membrane) Intermembrane space: the space between the two membranes: continuous with the cristae. Cristae space: the folded in regions of intermembrane space. Made fully in the cytosol first then transported into the mitochondria: this is a post-translational mechanism, recall, in co-translation the protein is being made as it is transported. Proteins entering the matrix space have n-terminus signal sequences: signal peptidase removes the signal after it gets to its destination. Proteins entering the outer membrane, inter membrane and intermembrane proteins have internal signal sequences: these sequences are not removed. The signal sequence forms an alpha helix: positively charged amino acids are on one side (red, hydrophobic amino acids are on the other side (green) Protein translocators: multi-subunit protein complexes that mediate protein movement across the mitochondrial membrane. Protein with signal sequence binds with tom on the outer membrane.
