What is the mitochondrial membrane permeable to?

The mitochondrial inner and outer membranes have contrasting permeability characteristics. The outer membrane is non-specifically permeable to all low-molecular-weight solutes, whereas the inner membrane is impermeable except through specific transporters.

What can pass through mitochondrial membrane?

The inner membrane is also loaded with proteins involved in electron transport and ATP synthesis. At the inner mitochondrial membrane, a high energy electron is passed along an electron transport chain. The energy released pumps hydrogen out of the matrix space.

Is the inner mitochondrial membrane permeable to H+?

The inner membrane is impermeable to H+, but the outer membrane of the mitochondria will allow H+ to pass through. Thus, placing mitochondria in a low pH buffer produces a H+ gradient that can generate ATP through ATP synthetase.

Is the inner mitochondrial membrane permeable to NADH?

a Effective transport of nadh into the mitochondria The mitochondrial membranes are not permeable to pyridine nucleotides, such as NAD+ or NADH, but a supply of NADH is essential in the mitochondria since it is the main substrate for the electron transport chain and, therefore, for the energy supply in the form of ATP.

Why is mitochondrial inner membrane impermeable?

Otherwise, the inner membrane is impermeable to most ions and small molecules—a property critical to maintaining the proton gradient that drives oxidative phosphorylation. This is because it contains proteins called porins, which form channels that allow the free diffusion of molecules smaller than about 6000 daltons.

What is the mitochondrial membrane?

The mitochondrial membrane is a protein-rich lamellar array that is characteristic of energy-transducing membranes. 90. The chemistry of its function as a respiratory unit was determined by fractionating the lamellae and separating the various protein complexes that are embedded within.

What is inner mitochondrial membrane?

The inner mitochondrial membrane (IMM) is the mitochondrial membrane which separates the mitochondrial matrix from the intermembrane space.

Why is the inner membrane of mitochondria folded?

To increase the capacity of the mitochondrion to synthesize ATP, the inner membrane is folded to form cristae. These folds allow a much greater amount of electron transport chain enzymes and ATP synthase to be packed into the mitochondrion.

Can malate across the mitochondrial membrane?

In the malate/aspartate shuttle, cytoplasmic NADH is used to convert cytoplasmic oxaloacetate to malate, which can be carried across the mitochondrial inner membrane by a dicarboxylate carrier by facilitated diffusion with no metabolic energy expenditure.

How permeable is the outer mitochondrial membrane?

The high permeability of the outer membrane is mediated by VDAC, which is the most common protein in the outer membrane and is permeable to molecules of up to 5000 daltons in its open configuration.

Are inner folded membrane of the mitochondria?

The inner membrane of the mitochondrion folds inwards, forming the cristae. This folding allows a greater amount of membrane to be packed into the mitochondrion.