James Batcheller Sumner discovered protein nature of enzymes received Nobel Prize for crystallization of enzymes in the year of 1946

1. James Batcheller Sumner
– discoverer of protein
nature of enzymes
Article written and published
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www.worldofchemicals.com

2. Biography & contributions
James Batcheller Sumner was born on November 19,
1887 – died on August 12, 1955. Sumner was an
American biochemist and Nobel laureate. Sumner
crystallized and isolated the enzymes and discovered
protein nature of enzymes.Sumner crystallized some
of the enzymes like Urease in the year of 1926,
another enzyme called Catalase crystallized in the
year of 1937.
Sumner was the receiver of various famous medals
and awards like Guggenheim Fellowship in the year of
1937, Scheele Award in the year of 1937, Nobel Prize
for crystallization of enzymes in the year of 1946.

3. Enzymes
Enzymes are large biological molecules accountable for the
thousands of chemical interconversions that sustain life. These
are usually very specific as to which reactions they catalyze and
the substrates that are involved in these reactions.They are
highly selective catalysts, greatly accelerating both the rate and
specificity of metabolic reactions, from the digestion of food to
the synthesis of DNA.
Enzymes are known to catalyze about 4,000 biochemical
reactions.Activators and Inhibitors are key factors that effect
enzymes activity.Like all catalysts, enzymes work by lowering the
activation energy for a reaction, thus dramatically increasing the
rate of the reaction.Enzymes are in general globular proteins and
range from just 62 amino acid residues in size

4. Mechanism of catalase
Catalase is an enzyme responsible for the degradation of
hydrogen peroxide. It is a protective enzyme present in
nearly all animal cells
The reaction of catalase occurs in two steps. A molecule of
hydrogen peroxide oxidizes the heme to an oxyferryl
species. A porphyrin cation radical is generated when one
oxidation equivalent is removed from iron and one from the
poryphyrin ring. A second hydrogen peroxide molecule acts
as a reducing agent to regenerate the resting state
enzyme, producing a molecule of oxygen and water.
Catalase composition
Catalase is a tetramer consisting of four identical,
tetrahedrally arranged subunits. Each 60 kDa subunit
contains a heme group and NADPH in its active center.

5. Catalase inhibitors
Cyanide
Azide
Hydroxylamine
Aminotriazole
Mercaptoethanol
Ascorbate
Peroxide

6. Catalase applications
Catalase applications in food industry
Catalase is used in food industry to remove
hydrogen peroxide from milk which is used to
make cheese. It is also applied to food packing,
in order to prevent the food from being oxidized.
Catalase applications in textile industry
In textile industry, catalase is used to remove
hydrogen peroxide from the textile fabrics, and
thus ensure that the finish products don’t contain
peroxides.

7. Catalase applications Cont ..
Catalase applications in optical equipments
It is also used to clean contact lenses.
Catalase applications in cosmetics industry
Catalase also used in beauty industry. Catalase and
hydrogen peroxide is added to some facial cares to
increase the amount of oxygen in the cells of the upper
epidermis.
Catalase applications in laboratories
Catalase is also often used in the laboratory as a tool that
is used to learn about how enzymes affect reaction rate.