I get too high the enzyme will lose

I am going to be carrying out a
literature review about enzymes, and then talk about 5 different experiments
that could be done for enzymes for temperature and then I will place the
references below my work.

With enzymes, they are very vigorous
therefore it can increase the rate of reaction without it being used up within
a chemical reaction, the only way in which an enzyme catalysed reaction happens
is if the substrate molecule goes with the active site of an enzyme molecule
which will then create an enzyme substrate complex. Enzymes are proteins: they
are tertiary globular proteins, which are folded in complicated shapes that
lets the small molecules to go into it and the place where the substrate
molecules fit into is named the active site. There are high temperature values
which its activity is the greatest being the optimum temperature.

The picture that I placed below displays
how this does work. In this picture 2 molecules that are tiny have connected to
make a much larger one. If the shape of the enzyme does change the active site
may not work meaning the enzyme has denatured. How enzymes can be denatured is
by high temperatures. The reason as to why this happens is because if the
temperature get too high the enzyme will lose its three dimensional shape.

 

Different enzymes work at different
temperatures. There are many enzymes in the body that have a certain role to do
for example, no matter what type of food we consume our diets are made of
things such as: carbohydrates fats plus proteins, and what breaks down these
carbohydrates, proteins and fats into smaller components are digestive enzymes.

The enzymes optimum temperature is where the
highest rate of reaction occurs the highest temperature in which enzymes may
work in the human body is usually around 37.

 

 

The Lock-and-key Hypothesis

This
hypothesis is how the enzyme catalyse substrate reaction, the figure of the
active site match to the form of the substrate.

When this molecule
bumps into the enzymes active site that is matching, a substrate shall lift
into the active site and then there will be an enzyme substrate complex.

What
catalyses the reaction is the enzyme, also what will create an enzyme product complex
is the enzyme and products being catalysed by the enzyme.

 

·        

The Induced-Fit Hypothesis

I the induced fit hypothesis, the shape of the
active site are not that complementary, but change shape in the presence of a
certain substrate to become complementary.

When a substrate molecule goes into an enzyme, and
its arrangement is correct, the shape of the enzymes active site does change so
that the substrate will fit into it then an enzyme substrate complex is formed,
this reaction is then catalysed and an enzyme product complex can be formed.

Temperature

An enzyme will eventually denature if the
temperature gets too high, as this will cause the enzymes weak bonds that keeps
it together to separate therefore the structure of it will change, this happens
mostly around 50-60 degrees.

Denatured enzymes do not work the image below shows
the relationship between temperature and enzyme activity.

 

   

Inhibitors

 

With
inhibitors, it does slow down the reaction taking place when the substrate is connecting
with the active site of an enzyme.  This
could be either non- changeable or changeable inhibitors, and with this
changeable inhibitor it can be either competitive or non-competitive.

 

  With a competitive inhibitor, it can connect to the active
site of an enzyme, this is because it has a shape that is like the substrate,
therefore this will prevent the substrate from connecting with the active site.

 

 

 

 

 

 

 

 

 

Non-competitive
inhibitors do not bind to the active site, therefore the substrate cant bind
the active site below is a comparison diagram:

 

 

 

 

 

 

 

 

 

With the pH it’s
a measure of the concertation of pH+ ions up against the OH- ions, so it is
either negatively or positively charged and has a high or low pH can change the
enzymes function, every single enzyme has an optimal pH in which it works at
its best, this being different to different enzymes, for example a lot of
enzymes work best at a pH of 7.35 pepsin with the stomach does work best a a pH
of 3.

 

 

Substrate
concentration

 

When all
enzymes are working all the time, adding more substrate won’t increase the rate
of reaction unless more enzymes are added.

 

 

 

 

The higher a
substrate concentration is, the rate of reaction will be faster, and this is
when all the active sites are filled so from this point to increase the rate of
reaction is only to add more enzymes.

 

 

The effect of temperature on enzyme reaction:

 

·       
What will be needed is :

·       
Three percent diastase

·       
One percent starch solution

·       
Iodine solution

·       
Dropping pipettes

·       
Syringes

·       
Stop block

·       
Test tubes

·       
Test tube racks

·       
Water baths

·       
Masking tape

·       
Stirrers

 

In a water put both tubes in it for around
two, minutes.

 Place
the diastase to the starch solution them ix this and start your stop watch,
write down when your solution became colourless.

At the temperature 20,30,35,40 and 50 repeat
this at all of these temperatures.

Place 5 millimetres of a percent of starch
into a test tube and put two drops of iodine solution.

In another test tube place 4 millimetres of
diastase enzyme in it.

 

The effect of temperature on enzyme reaction:

The enzyme reaction will take place with five
different temperatures, firstly what will happen is you will run a reaction at
the temperatures you are going to be using with e3nzyme and one reaction being
30 degrees without enzyme for a sum of 6 reactions.

Label the 6 tubes, place 2 drops of lattice
acid and 2 drops of PMS/INT/NAD, and 2 drops of buffer to the tubes. Into tube
#1 add 2 drops of water, make sure before this you have the timer and a
pippete, make sure to go quickly and make sure you are adding the enzyme
properly, and putting these tubes in the water bath.

Then time this reaction after 4 minutes
examine these tubes as different colours will appear and write down the
different colours that came up. 

 

 

 

The effect of temperature on enzyme reaction:

 Place
20 cm of a buffer to a graduated cylinder

With a dropper add a drop of washing up liquid

The place 5 grams of chopped radish to this
cylinder

Place 2 cm cubed of hydrogen peroxide to the
boiling tube

Put the cylinder up and the boiling tube in a
water bath that is ice cold until the wanted temperature is reached

Put hydrogen peroxide in the cylinder

Write down the volume within the cylinder.

Read the volume again after a measured amount
of time then subtract the volume you got in the beginning from your final
volume to get the volume of foam.

Redo this procedure from step 3 for at the
very least 4 more temperatures to include a sample in the 50 to 60 degree
range.

 

 

The effect of temperature on enzyme reaction:

Fresh
catalase solution
20%
Hydrogen peroxide solution
Water
baths
10
mL graduated cylinder
teat
dropper
 Boiling tubes that are the same but
different.
Stop  watch

Procedure

Firstly you must label all 8 of your test
tubes with each temperature and the other 8 test tube from hydrogen peroxide
and with its temperature, then put these boiling tubed in the test tube rack.

Place a drop of catalase enzyme within a
catalase tube this being labelled 0oC.

Then place1mL of hydrogen peroxide in to the
tube for hydrogen peroxide making sure to label it 0oC.

Put the 2 boiling tubes in the 0oC water bath
for around 10, minutes to allow for the equilibrium of temperature.

Place hydrogen peroxide to catalyse then begin
the stop watch.

Then measure the column of bubble after 35
seconds and record this.

Then repeat step 2-6 from the other
temperatures.

The effect of temperature on
enzyme reaction:

A water bath needs to heated up to 25 degrees

5 cm cubed of 4 percent casein solution has to
be placed in a test tube plus 5 cm cubed of 0.5 percent trypsin must be added
to another tube.

Then put both in a water bath until it goes to
the right temperature required,

Then the same quantity of casein solution must
be placed into another test tube and five cm cubed distilled water in a fourth
test tube.

Then in the last test tube you have put 5 cm
cubed of distilled water in the fifth test tube plus 5 cm cubed of casein in
the last test tube.

 

This must all be put in a water bath.

 

 

 

 

The effect of temperature on
enzyme reaction:

Make sure to place a
sticker on the test tube you are examining and label it.

Put five drips of phenolphthalein
within this test tube

Using a measuring cylinder get up to 5cm cubed of the milk properly,
then put it in the test tube.

Then use another measuring cylinder where you will now, get up to 7m
cubed of sodium carbonate, once again place it into the test tube then the solution
shall turn into the colour of pink.

Make sure to place a thermometer within the test tube to check to temperature.

Make sure to place the test tube within a water bath, and allow the
contents within it to react till it is the same temperature as the water bath
itself.

Change the thermometer that is inside the test tube to a glass rod.

Measure around 1cm cubed of the lipase with the use of an 2c cubed
syringe, from the beaker in the bath of water for the temperature that you are
examining.

Begin your stop watch when you have put the lipase within the test
tube.

So that this solution loses the pink colour that it had what you
need to do is mix up the content in the test tube.

Write down the time after you have stopped the stopwatch.

 

1st method: this experiment is easy
to carry out because not a lot of steps are required to finish this experiment,
also the person who is doing this experiment does not have to do any
calculations so this experiment is time affective. An error can occur in this
experiment as if the person were to put more than 2 drops of iodine in it by
accident it could affect the results they have obtained.  Iodine is carcinogenic therefore it  could cause cancer, and if this goes into the
persons eye it can make them blind therefore the person must fully the safety
rules when using these equipment’s and if they don’t these risks may happen to
the person doing the experiment.

 

2nd method: The advantage to this
experiment is that it isn’t time consuming as it is very quick however in this
experiment some errors could occur for instance: if the timer was not working
the person could have gotten different results therefore the colour that was
obtained may have been wrong, if more than 2 drops of buffer was added to the
tubes then once again the results obtained could be inaccurate, also another
disadvantage could be that this experiment can be subjective as one person may
see blue and another person my see purple instead.

3rd method The disadvantage to this
test is that if the hydrogen peroxide were to be inhaled it ca affect the body
and or if it were to come into contact with the persons eyes or skin, and
advantage to this experiment is that it is not time consuming if it were to be
done properly without any errors for example: placing more than 2cm cubed of
hydrogen peroxide in the boiling tube.

4thmetod: An error that could occur
in this experiment could be that the timing may be inaccurate if the person
wasn’t looking at the stop watch properly, this could also be a time consuming
experiment as you have to repeat step 2-6 for the other temperatures, and
advantage of this experiment however is the method is easy to follow.

5th experiment: You ca repeat this experiment many
times if errors occur which is an advantage. I f the person doing this test
studies different temperatures on different days for the same investigation,
the action of the enzyme will change plus it won’t be a fair test, also the
glass water is breakable so if it were to break then the person doing this
experiment may have to repeat this whole experiment or get a new beaker which
is a waste of money.

Out of all 5 methods the best one has to be
the second  experiment as it is the most
time effective compared to all of the other 4 methods and if an error does
occur it is a repeatable experiment, and if the safety procedures are followed
properly in this experiment no risks will occur.