Properties of enzymes

Properties of Enzymes :

         There are two main properties of  enzymes 

    1. Enzyme efficiency :

                     The most important biochemical characteristics of Living Organism is its ability to achieve large number of rapid chemical conversion at temperature below 40 degree Celsius while parallel chemical reactions in the laboratory process at the high temperature this is due to catalytic nature of enzymes.

                    Enzymes increase the velocity of the chemical reactions like other catalyst it also reduce the activation energy required for that reaction to proceed.

       Before the chemical reactions occur the reacting molecule must gain the certain minimum amount of energy called as activation energy 

Greater the required activation energy  slower the rate of the reaction

Reactions	Catalyst	Activation Energy	Velocity
Hydrolysis of sucrose	Acid Invertase	26,000 11,000	1.0 1011

* TON ( turn over number)

Number of substrate molecules convert into the products by an enzyme per unit time called TON  of that enzyme 

Enzyme	TON
Carbonic anhydrase	600000
catalase	13000

2. Enzyme specificity :

Enzymes are highly specific in their action when compared with the chemical catalyst the occurrence of thousands of catalyst as enzymes in the biological system might be due to specific nature of enzymes 

There are three sub-classes

1. Stereo specificity :

The enzymes act on the on one isomer and therefore exhibit stereo-isomerism  most of the biological reactions are extremely specific in production of stereo-isomers

    Ex. succinic acid which  hydrogenate  to gives only the formic acid 

        and no maleic acid

2. Reaction specificity :

When the same substrate can undergo different type of reactions which catalyzed by separate enzymes called as reaction specificity of that enzymes

3. Substrate specificity :

i) Absolute substrate specificity  :

certain enzymes act only on one substrate called absolute 

substrate specificity

Ex. 

ii) Relative substrate specificity :

 Same enzyme act on structurally related substances

(depend on specific group)

Ex. 

iii) Broad specificity :

 Some enzymes act on several closely related substrate commonly known 

 as broad substrate specificity