What are the optimum operating conditions for enzymes?
type of enzymes
Conditions - what could affect enzyme activity?
chosen
concentration of
Oxidoreductases
dependent enzyme to test on
independent condition for the test
methods
equipments / materials
testing technique
substrate
enzyme
pH
temperature
amount of energy
surface area of enzymes and substrate
inhibitors
proteins can be denatured at certain temperatures leading to change of shape of enzymes, can no longer bind with substrate. All reactions are faster at a higher temperature. However, enzyme-catalyzed reactions become slower or stop if the temperature becomes too high. The optimum temperature is usually around body temperature (37°C).
higher concentration of substrate increases the rate of reaction as the available enzymes would be working at their maximum rate
speeds up reactions until substrate amount Is limited
competitive
noncompetitive
higher or lower in acid or alkaline can interfere enzyme structure
more heat = more kinetic energy (however see 'temperature')
competes for active site so the substrate could not bind with the enzyme
alters the structure of enzyme as it binds to the other parts of the enzyme so the active site is no longer functional
Transferases
Hydrolases
Lyases
Isomerases
Ligases
transfers chemical group from one molecule to another
catalyze the joining of two large molecules by forming a new chemical bond
catalyze the breakdown of chemical bonds through methods other than hydrolysis or oxidation
catalyze bond cleavages by reaction with water resulting in the division of a larger molecule into smaller molecules
catalyze electron transfer from one molecule to another
catalyze reactions involving a structural rearrangement of a molecule
present in the metabolism and genome of most living organisms
salinity
changes salt concentration, adds or removes cations & anions, disrupts bonds, disrupts 3D shape, denatures protein
where can enzymes be found
digestive system
mouth - salivary glands
amylase
stomach
protease
pancrease
lipase, protease, pancreatic amylase
enzyme rich foods e.g. pineapples papayas
enzyme supplements
enzyme laundry detergent
Type of reactions
gas production
digestion of a solid
digestion of a liquid
colour change
testing for catalase enzyme by detecting the oxygen gas produced
using paper discs soaked in 0.05% catalase solution put into different temperatures of 0.5% hydrogen peroxide. The reaction rate is then timed from the time the disc reaches the bottom to when the discs float to the surface.
Catalase is a common enzyme found in most living organisms. Catalyzes the decomposition of hydrogen peroxide to water and oxygen.
temperature of 0.5% hydrogen peroxide, since temperature Is one of the factors that affect the rate of reaction, and the chosen dependent enzyme, catalase, acts on hydrogen peroxide.
water bath should be used to hold the samples at a constant temperature
37ºC Is our body's temperature therefore the different temperatures range from here. Collecting data from 5 samples, the temperature of 0.5% hydrogen peroxide would be 10ºC, 30ºC, 50ºC, 70ºC, and 90ºC. Water should not boil for safety reasons.
catalase solution 5mL concentration 0.05% for paper discs to soak
0.5% hydrogen peroxide at temperature 10ºC, 30ºC, 50ºC, 70ºC, and 90ºC as 5 samples (independent variable)
hole puncher for making paper discs
tweezers to transfer paper discs from catalase solution to hydrogen peroxide
measuring cylinder to measure 10mL of hydrogen peroxide Into each tube
6 tubes, one for controlled, other 5 for the samples
stopwatch to time
sharpie to mark each sample correspondingly
beaker to hold catalase solution
aim: to Investigate the optimum operating conditions for enzymes
by testing the rate of reaction of catalase at different temperatures of hydrogen peroxide
goggles, gloves, aprons, and hair-tie for long hair
uncontrolled
the environment - temperature fluctuations can affect the experiment as temperature Is one of the factors that affect the rate of reaction, therefore a water bath should be used to control the temperature of the samples
Contamination - contamination can occur and affect the experiment,
can be observed
can be observed
can be observed
can be observed