ENZYME
ENZYME
Characteristics of enzymes
• Protein in nature.
• Biological catalysts. Speed up reactions without being changed or used up.
• Act on reversible reaction.
• Action of enzymes is specific
• Work best at a certain range of pH and temperature.
• Action of enzymes is affected by inhibitor
Characteristics of enzymes
Protein
A + BC
enzyme
SpecificitypH
Biological catalyst
substrate
enzyme
active site
substrate
Action of enzyme (Anabolic reaction)
enzyme
substrate
enzyme
product
enzyme-substrate complex
enzyme-product complex
Action of enzyme (catabolic reaction)
products
enzyme
enzyme-product complex
enzyme
substrate
enzyme-substrate complex
Lock and key hypothesis
Substrate
Enzyme
product
product
Lock and key hypothesis
SHAPES
DON’T
MATCH
Factors affecting enzyme actionSubstrate concentration
Max. RateR
ate
of r
eact
ion
Substrate conc.
Factors affecting enzyme actionSubstrate concentration
Factors affecting enzyme actionTemperature
Rat
e of
rea
ctio
n
Temperature( OC)
0 10 20 30 40 50
Factors affecting enzyme actionTemperature
• Each enzyme works best at a particular temperature - _____________________.
• When temperature is lower than optimum temperature, activity of enzyme become ________. At low temperature, enzymes become _____________. They become _________________ when the temperature is raised.
lowerinactive
active again
optimum temperature
Factors affecting enzyme actionTemperature
• Above the optimum temperature, heat changes the _______ of enzymes and their _____________, __________ their activities.
• When temperature is too high (above 60oC), most enzymes are ____________, and lose they catalytic property permanently.
shapeactive sites decreases
denatured
Factors affecting enzyme actionpH
Rat
e of
rea
ctio
n
pH
Application of Enzymes
Washing Powder
SCIENCE SECTION CURRICULUM DEVELOPMENT INSTITUTEEDUCATION DEPARTMENT