1. PROFESSOR: Dr. Bries , Florence R
Group #6
Khafi Makoo, Noorallah
Ahmady, Kiyanoosh

2. 1. To be able to isolate RNA from yeast.
2. To be able to get the percentage by mass of
RNA from yeast.
3. To be able to identify products of hydrolysis
of RNA.
4. To perform tests for identification of
products of RNA hydrolysis.

3. • It is a Genetic material of certain viruses.
• In RNA viruses, the RNA directs two processes:
1. Protein Synthesis
2. Replication
• Made up of a single strand of nucleotides.
• Directs the middle steps of protein production.
• It is also a Polymer of Purine and Pyrimidine
Ribonucleotides linked through 3’-5’ Phosphodiester
bridges.
• With Uracil instead of Thymine and D-ribose instead
of 2-deoxy-ribose.

4. Materials
• 1% NaOH
• Filter Paper
• Litmus Paper
• 95% C2H5OH
• Concentrated HCL
• acetic acid
• Diethyl ether

5. • To isolate RNA from yeast. Yeast is suitable though
yeast contains more RNA than DNA. About 97% is
rRNA and 3% is mRNA.
• RNA expression is one way of measuring gene
activity. As genes are turned on, mRNA levels for
those genes increase, generally resulting in
increased protein expression. While cells have
many ways of regulating proteins, differences in the
functional state of the cell correlates directly with
changes in mRNA levels.

6. Materials
• Mortar and pestle
• Erlenmeyer Flask
• 0.2% NaOH
• 10% NaOH
• 0.5% CuSO4

7. • Chemical process involving the addition of water
causing a molecule to cleave into two parts
Nucleoprotein
Nucleic Acids
Protein
Phosphate
Nucleosides
D-ribose
Pyrimidine
Purine

8. Materials
• NaOH
• CuSO4
• 10% NH4OH
• 2% AgNO3
• Benedict’s Reagent
• 0.2M Ammonium Molybdate

9. -test to detect the presence of Peptide bonds.
Principle: Formation of purple colored product.
Cu2+ forms coordination complex with lone
pair of Nitrogen of peptid bonds.
Reagents: NaOH and CuSO4

10. -test to detect the presence of Purine Bases.
Principle: Base Hydrolysis of N-β-glucosidic bonds
between purine bases and ribose or deoxyribose
results in a release of purine bases(A and G)
caused by NH4OH. Ag+ precipitate caused the
formation of foamy gelatinous substance.
Reagents: AgNO3 and NH4OH

11. -test to detect the presence Reducing Sugars such as
monosccharides/disaccharides.
Principle: Cu2+ react with reducing sugars = precipitate
of cuprous oxide (Cu2O) produces a change in the
Benedict’s reagent from blue to green or reddish-orange,
depending on amount of reducing sugar. The
cyclic sugar is reduced to linear aldehyde.
• Green = small amount of reducing sugars
• Red-orange = abundance of reducing sugars
Reagents: NaOH, Cu2+ SO4 and NaK Tartrate.

12. -test for Inorganic Phosphate.
Principle: Hydrolysis of phosphodiester Bonds
forming yellow precipitate of Ammonium
Phospho molybdate.
Reagents: (NH4)6 Mo7O24 · 4H2O and H2SO4

13. Test Result
Biuret’s Test Purple Solution
10% NH4OH &
2% AgNO3
Benedict’s Test Green Solution
Ammonium
Molybdate

14. Test
Biuret’s Test
10% NH4OH &
2% AgNO3
Benedict’s Test
Ammonium
Molybdate

15. Test Result
Biuret’s Test Blue/Purple Solution
10% NH4OH &
2% AgNO3
Benedict’s Test Orange or Break Red
Solution
Ammonium
Molybdate

16. Test Result Result
Biuret’s Test Purple Solution
Blue/Purple
Solution
10% NH4OH &
10% AgNO3
Benedict’s Test
Green
Solution
Orange or Break
Red Solution
Ammonium
Molybdate

17. 1. Based in this experiment, what are the steps
used in identifying RNA in yeast?
 Grinding
 Heating
 Filtering

18. 2-1. What are the products of RNA hydrolysis?
 Nucleobases (A, G, U and C)
 Sugar (D-ribose)
 Phosphate

19. 2-2. Name the qualitative tests to characterized
these products. Are these tests specific for RNA?
 Bial’s Test
- A Test used to detect the presence of pentoses
with a test reagent consisting of Orcinol, HCl
and Ferric chloride
- specimen is heated with solution of Orcinol,
HCl and FeCl3
- pentoses : dehydrated to furfural = reacts with
Orcinol to form a green product

20.  Wheeler and Johnson's test
- A qualitative test for the pyrimidine
bases Cytosine, Thymine and Uracil, which
produces a green coloration when the sample
is treated with bromine water. The addition of
barium hydroxide will turn the liquid purple.
- Addition of Ba(OH)2 = purple.

21.  Murexide Test
- Murexide (NH4C8H4N5O6 or C8H5N5O6.NH3) or
ammonium purpurate [MX] = ammonium salt of purpuric acid.
- a reaction giving rise to murexide when uric acid or
a related compound is heated with nitric acid and the
product is treated with ammonia—called also murexide
reaction
- Test for presence of uric acid = white, odorless,
tasteless crystalline substance from purine degradation
- Positive : yellow residue
- A & G : purines = 2-ringed crystalline organic base –
a uric acid; heterocyclic aromatic org. compound composed
of pyrimidine ring fused w/ an imidazole ring

22. 3. What are differences of RNA and DNA?
DNA RNA
Based on
Function
Responsible for the storage &
transmission of the genetic
material
Involve in the manufacture of
proteins
Based on sugar
composition
2-deoxy-D-ribose D-ribose
Based on
Pyrimidine base
composition
A,G,C,T
With Thymine
A,G,C,U
With Uracil
Based on
Structure
Double Helix Made up of a single strand