Enzymes are capable of acting on only one substrate. Example: Urease acts only on urea to produce ammonia and CO2.
Enzymes are highly specific in two ways—first in the reaction catalysed and second in the choice of reactants called substrates.
Turnover number is defined as the number of substrate molecules converted into product per unit time when the enzyme is fully saturated with substrate. It depends upon its molecular weight. Example: Transfer of Carbon dioxide from tissues into blood and then to the alveolar air would be less complete in the absence of an enzyme. Carbonic…
Enzymes are sometimes considered under two broad categories: Chemically, the enzymes may be divided into two categories: The functional unit of enzyme is known as holoenzyme, which is oft en made up of apoenzyme (the protein part) and coenzyme (non-protein part). The term prosthetic group is used when the non-protein part (tightly) covalently binds with the apoenzyme. The coenzyme or…
1836 – Berzelius coined the term catalysis. 1878 – Kuehne worded the word enzyme. 1883 – Buchner isolated enzyme from yeast zymase. 1926 – James Sumner isolated from Jack Beans. He got noble prize in 1940. 1930 – Northrop crystallised proteolytic enzyme from gastrointestinal tract.