kreatinkináz

Kreatinkináz, also known as creatine kinase, is an enzyme found in the body that plays a crucial role in energy metabolism. It is primarily located in the heart, brain, and skeletal muscles. The enzyme catalyzes the reversible transfer of a phosphate group from creatine to ADP, producing ATP and creatine. This reaction helps maintain the body's energy supply, particularly during intense physical activity.

Kreatinkináz is a dimeric enzyme, consisting of two subunits: an M subunit and a B subunit. The M subunit is responsible for the binding of creatine, while the B subunit binds to ADP. The enzyme has two distinct catalytic sites, one for each subunit, which allows it to catalyze the reaction in both directions.

There are five known isoforms of kreatinkináz, each with slightly different properties and functions. The most well-known isoform is MM, which is found in skeletal muscles. The other isoforms include MB, BB, MI, and BI, each with specific roles in different tissues and under various conditions.

Kreatinkináz activity can be measured in biological samples to assess muscle damage, as it is released into the bloodstream when muscle cells are damaged. Elevated levels of kreatinkináz in the blood are often used as a marker for muscle injury or damage.

In summary, kreatinkináz is a vital enzyme in energy metabolism, particularly in muscles. Its activity is crucial for maintaining ATP levels and can be used as a diagnostic marker for muscle damage.