Aug 12, 2020 · In other words, a high kcat/Km ratio means the enzyme works well with not much substrate. This is called catalytic efficiency because if the enzyme is efficient, it means it doesn't need much substrate to achieve a high reaction rate.

Nov 19, 2016 · Comparing based on $k_{cat}/K_m$ gives you information about rates in the low (respective) substrate regime, just as comparing $k_{cat}$ gives information about rates in the high (respective) substrate regime.

Oct 1, 2024 · The catalytic constant, kcat, is another crucial parameter in enzyme’s kinetics. It is defined as the number of substrate molecules converted into product by an enzyme per unit time when the enzyme is fully saturated. kcat is often referred to as the “turnover number.”

While that might seem like a high value, there are enzymes known (carbonic anhydrase, for example) that have Kcat values of 106/second. This astonishing number illustrates clearly why enzymes seem almost magical in their action.

kcat/km is the ratio of the turnover number and the Michaelis constant. It is also called the specificity constant because it reflects how specific the enzyme is for the substrate. The higher the kcat/km, the more efficiently the enzyme converts the substrate into a product.

Jun 13, 2022 · The reciprocal form of the expression of kcat / KM shows that kcat / KM is a harmonic sum of kinetic terms that correspond to the heights of the transition states relative to the free enzyme. Then, it is demonstrated that the height of the highest transition state has the dominant influence on kcat / KM.

Kcat gives an indication of how fast an enzyme can convert substrate into product, while Km provides information about the enzyme's affinity for the substrate. Enzymes with a high Kcat value are considered to be efficient catalysts, as they can convert substrate into product at a rapid rate.

Notice \(k_2\) describes an irreversible reaction as opposed to an equilibrium expression, when compared to k-1 and k1. k2 here is also known as kcat, the catalytic efficiency of enzyme.

Jun 5, 2024 · A high kcat value indicates an enzyme that efficiently catalyzes a reaction, converting a significant amount of substrate into product per unit time. Conversely, a low kcat value suggests a less efficient enzyme that might struggle to process substrates quickly.

The higher this value the more specific the enzyme is for that substrate. This is because a high value of k cat and a low value of K m are expected for the best substrates.