give a simple mechanism for an enzyme catlyzed rxnSolution E

give a simple mechanism for an enzyme catlyzed rxn

Solution

Enzyme catalysis is the catalysis of chemical reactions by specialized proteins known as enzymes. Catalysis of biochemical reactions in the cell is vital due to the very low reaction rates of the uncatalysed reactions.
An enzyme catalyzes a reaction by:
1. supplying the energy to speed up a reaction
2. lowering the energy of activation of a reaction
3. lowering the G of a reaction
4. changing the equilibrium of a spontaneous reaction
5. increasing the amount of free energy of a reaction
Three main steps of cycle of enzyme substrate interactions:
(1) Enzyme + substrate
(2) Enzyme-substrate complex
(3) Enzyme + product
Enzyme speeds up the chemical reaction. So, it would speed the cells for life and live.
A living cell contains thousands of enzymes, however, not all of them need to be active at any given time. There are several mechanisms of enzymatic activity regulation, allowing strict control over chemical reactions in a living cell . Enzyme activity can be regulated at many levels:
* the expression of the enzyme-encoding genes can be regulated, and as a result the number of enzyme molecules in a cell may vary,
* the availability of substrates and cofactors affects enzyme activity,
* enzymatic activity can be influenced by posttranslational modifications