The peripheral-type benzodiazepine receptor: a protein of mitochondrial outer membranes utilizing porphyrins as

S H Snyder1, A Verma, R R Trifiletti

  • 1Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.

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Mitochondrial Precursor Proteins01:39

Mitochondrial Precursor Proteins

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Porin Insertion in the Outer Mitochondrial Membrane01:12

Porin Insertion in the Outer Mitochondrial Membrane

Porins are beta-barrel proteins translocated to the mitochondrial outer membrane through the TOM complex into the intermembrane space. Porin precursors bind TIM chaperones within the intermembrane space and are guided to the Sorting and Assembly Machinery complex or SAM complex on the outer mitochondrial membrane.
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Protein Transport into the Inner Mitochondrial Membrane01:34

Protein Transport into the Inner Mitochondrial Membrane

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Transport of mitochondrial precursors across the TIM23 channel is driven by...
Structure of Porins01:21

Structure of Porins

Mitochondria, chloroplasts, and gram-negative bacteria have transmembrane, beta-barrel proteins called porins to mediate the free diffusion of ions and metabolites across the membrane. Mitochondrial porin precursors contain conserved amino acid sequences called beta signals at their C-terminal. Beta signals have a  motif of PoXGXXHyXHy (Po-Polar, X-Any amino acid, G-Glycine, Hy-LargeHydrophobic), which are crucial for precursor recognition to initiate precursor assembly. Beta-barrel precursors...
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Ligand-Gated Ion Channel Receptor: Gating Mechanism

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