Enzymkomplekser

Enzymkomplekser, also known as enzyme complexes or multi-enzyme complexes, are assemblies of two or more enzymes that function together to catalyze a sequence of biochemical reactions. These complexes often bring together enzymes that catalyze sequential steps in a metabolic pathway. This arrangement offers several advantages, including increased efficiency and control over the reaction sequence. By physically associating, the intermediates of a reaction pathway are held in close proximity to the subsequent enzymes, minimizing diffusion distances and preventing their loss or degradation. This spatial organization can also lead to substrate channeling, where a product of one enzyme is directly passed to the next enzyme in the complex without entering the bulk solution.

The formation of enzyme complexes can be regulated, allowing cells to control metabolic flux. This regulation can occur through allosteric mechanisms, covalent modifications, or changes in the expression of the genes encoding the individual enzymes. Examples of important enzyme complexes include pyruvate dehydrogenase complex, which plays a key role in cellular respiration by linking glycolysis to the citric acid cycle, and fatty acid synthase, responsible for the de novo synthesis of fatty acids. The structure and function of these complexes are crucial for a wide range of cellular processes and metabolic pathways.