Question

How pyruvate enters mitochondria?

Answer 1

Pyruvate is a major chemical compound in biochemistry. It is the glucose metabolism output known as glycolysis. One glucose molecule breaks down into two pyruvate molecules, which are then used to provide additional energy.

Complete answer:
Mitochondria are membrane-bound cell organelles (mitochondria, singular) that generate most of the chemical energy needed to stimulate the cell's biochemical reactions. Chemical energy generated by mitochondria is stored in a small molecule called adenosine triphosphate (ATP).

Mitochondria contain small chromosomes of their own. In general, mitochondria and therefore mitochondrial DNA are inherited only from the mother. Mitochondria are membrane-bound organelles, but they are membrane-bound with two different membranes. And that's pretty unusual for an intercellular organelle. These membranes function for mitochondria, which is essentially the production of energy. That energy is produced by having chemicals in the cell go through pathways, in other words, be converted.

In eukaryotic cells, pyruvate decarboxylation occurs within the mitochondrial matrix after transport of the substrate, pyruvate, from the cytosol. The transport of pyruvate to mitochondria is via the transport protein translocase of pyruvate. Pyruvate translocase transports pyruvate in a symport fashion with a proton and is therefore active, consuming energy.

"The transport of pyruvate through the outer mitochondrial membrane appears to be easily accomplished via large non-selective channels, such as voltage-dependent anion channels, which enable passive diffusion" and the transport through the inner mitochondrial membrane is mediated by mitochondrial pyruvate carrier 1 (MPC1) and mitochondrial pyruvate carrier 2 (MPC2).

Upon entry into the mitochondria, the pyruvate is decarboxylated, producing acetyl-CoA. This irreversible reaction traps acetyl-CoA in the mitochondria (the acetyl-CoA can only be transported out of the mitochondrial matrix under conditions of high oxaloacetate via the citrate shuttle, a TCA intermediate that is normally sparse).

Note: The inner mitochondrial membrane is compartmentalized into numerous folds called crystals, which expand the surface area of the inner mitochondrial membrane and enhance its ability to produce ATP. For typical liver mitochondria, the area of the inner membrane is about five times larger than the outer membrane.