Download polynucleotide chain

STRUCTURE OF NUCLEIC
ACIDS
1
SIGNIFICANCE OF NUCLEIC ACID STRUCTURE
IN MEDICINE
DNA: gene for β globine
Disease: sickle cell anemia
2
3
STRUCTURE OF NUCLEIC ACIDS:
DNA:
1. Basic structure of DNA
2. Structure of DNA nucleotide
3. Bases in DNA
4. Phosphodiester bond
5. Complementary pairing of bases
6. Basic structure of RNA
7. Structure of RNA nucleotide
8. Basic types of RNA
4
1. BASIC STRUCTURE OF DNA:
DNA: polymer of nucleotides (polynucleotide chain)
usually two polynucleotide chains (strands) forming a double
helix
[FIG.]
5
6
2. STRUCTURE OF DNA NUCLEOTIDE:
• Nucleotide: nitrogen-containing base + sugar pentose +
phosphate
[FIG.]
• Nucleoside: nitrogen-containing base + sugar pentose
• Nitrogen-containing bases: adenine, guanine, cytosine, thymine
• Pentose: deoxyribose (deoxyribonukleotide)
[FIG.]
• Phosphate [FIG.]
7
8
2. STRUCTURE OF DNA NUCLEOTIDE:
• Nucleotide: nitrogen-containing base + sugar pentose +
phosphate
[FIG.]
• Nucleoside: nitrogen-containing base + sugar pentose
• Nitrogen-containing bases: adenine, guanine, cytosine, thymine
• Pentose: deoxyribose (deoxyribonukleotide)
[FIG.]
• Phosphate [FIG.]
9
10
2. STRUCTURE OF DNA NUCLEOTIDE:
• Nucleotide: nitrogen-containing base + sugar pentose +
phosphate
[FIG.]
• Nucleoside: nitrogen-containing base + sugar pentose
• Nitrogen-containing bases: adenine, guanine, cytosine, thymine
• Pentose: deoxyribose (deoxyribonukleotide)
[FIG.]
• Phosphate [FIG.]
11
12
3.
BASES IN DNA:
• Purine bases: adenine (A), guanine (G)
• Pyrimidine bases: cytosine (C), thymine (T) [FIG.] [FIG.]
13
14
15
4. PHOSPHODIESTER BOND:
Phosphodiester bond: bond via OH group of the 3´carbon of
deoxyribose of one nucleotide and phosphate of the 5´carbon of
deoxyribose of the second nucleotide
The backbone of polynucleotide chain: repetated deoxyribose
and phosphate
[FIG.]
3´end and 5´end of polynucleotide chain
Polynucleotide chains in the double helix are antiparallel
16
17
4. PHOSPHODIESTER BOND:
Phosphodiester bond: bond via OH group of the 3´carbon of
deoxyribose of one nucleotide and phosphate of the 5´carbon of
deoxyribose of the second nucleotide
The backbone of polynucleotide chain: repetated deoxyribose
and phosphate
[FIG.]
3´end and 5´end of polynucleotide chain
Polynucleotide chains in the double helix are antiparallel
18
5. COMPLEMENTARY PAIRING OF BASES:
Binding of polynucleotide chains is mediated by bonds between
bases.
Complementary pairing of bases:
• A (purine) & T (pyrymidine): 2 hydrogen bonds
• G (purine) & C (pyrymidine): 3 hydrogen bonds
[FIG.] [FIG.]
19
20
21
6. BASIC STRUCTURE OF RNA:
RNA: polymer of nucleotides (polynucleotide chain)
usually one polynucleotide chain (strand)
22
7. STRUCTURE OF RNA NUCLEOTIDE:
•
•
•
Pentose: ribose (ribonucleotide)
[FIG.]
Bases in RNA:
• Purine bases: adenine (A), guanine (G)
• Pyrimidine bases: cytosine (C), uracile (U) [FIG.]
Phosphate
Phosphodiester bond
3´end and 5´end of polynucleotide chain
[FIG.]
More complex 3-D conformation of RNA polynucleotide chain:
intramolecular complementary pairing (A-U, G-C)
[FIG.] [FIG.]
23
24
7. STRUCTURE OF RNA NUCLEOTIDE:
•
•
•
Pentose: ribose (ribonucleotide)
[FIG.]
Bases in RNA:
• Purine bases: adenine (A), guanine (G)
• Pyrimidine bases: cytosine (C), uracile (U) [FIG.]
Phosphate
Phosphodiester bond
3´end and 5´end of polynucleotide chain
[FIG.]
More complex 3-D conformation of RNA polynucleotide chain:
intramolecular complementary pairing (A-U, G-C)
[FIG.] [FIG.]
25
26
7. STRUCTURE OF RNA NUCLEOTIDE:
•
•
•
Pentose: ribose (ribonucleotide)
[FIG.]
Bases in RNA:
• Purine bases: adenine (A), guanine (G)
• Pyrimidine bases: cytosine (C), uracile (U) [FIG.]
Phosphate
Phosphodiester bond
3´end and 5´end of polynucleotide chain
[FIG.]
More complex 3-D conformation of RNA polynucleotide chain:
intramolecular complementary pairing (A-U, G-C)
[FIG.] [FIG.]
27
28
7. STRUCTURE OF RNA NUCLEOTIDE:
•
•
•
Pentose: ribose (ribonucleotide)
[FIG.]
Bases in RNA:
• Purine bases: adenine (A), guanine (G)
• Pyrimidine bases: cytosine (C), uracile (U) [FIG.]
Phosphate
Phosphodiester bond
3´end and 5´end of polynucleotide chain
[FIG.]
More complex 3-D conformation of RNA polynucleotide chain:
intramolecular complementary pairing (A-U, G-C)
[FIG.] [FIG.]
29
30
31
8. BASIC TYPES OF RNA:
• mRNA (messenger RNA): transcription → template for translation
[FIG.]
• rRNA (ribosomal RNA): 4 types in eukaryotes → ribosomes [FIG.]
• tRNA (transfer RNA): adaptor recognizing proper codon for
corresponding amino acid
[FIG.]
• Small RNA: role in RNA splicing etc.
32
33
8. BASIC TYPES OF RNA:
• mRNA (messenger RNA): transcription → template for translation
[FIG.]
• rRNA (ribosomal RNA): 4 types in eukaryotes → ribosomes [FIG.]
• tRNA (transfer RNA): adaptor recognizing proper codon for
corresponding amino acid
[FIG.]
• Small RNA: role in RNA splicing etc.
34
35
8. BASIC TYPES OF RNA:
• mRNA (messenger RNA): transcription → template for translation
[FIG.]
• rRNA (ribosomal RNA): 4 types in eukaryotes → ribosomes [FIG.]
• tRNA (transfer RNA): adaptor recognizing proper codon for
corresponding amino acid
[FIG.]
• Small RNA: role in RNA splicing etc.
36
37
8. BASIC TYPES OF RNA:
• mRNA (messenger RNA): transcription → template for translation
[FIG.]
• rRNA (ribosomal RNA): 4 types in eukaryotes → ribosomes [FIG.]
• tRNA (transfer RNA): adaptor recognizing proper codon for
corresponding amino acid
[FIG.]
• Small RNA: role in RNA splicing etc.
38
LITERATURE
• Alberts B. et al.: Essential Cell Biology. Garland Science. New York
and London, pp. 171-179 & 232-257, 2010
39