Nucleotide Chemistry

NUCLEOTIDE CHEMISTRY

STRUCTURE OF NUCLEOTIDES BASE PO4

PO4

PO4

CH2

O

’

5 4’

1’ 3’

OH

N – glycosidic bond

2’

OH

Nucleoside

Nucleoside monophosphate Nucleoside diphosphate Nucleoside Triphosphate

Nucleotides

NITROGENOUS BASES BASE

NUCLEOSIDE

NUCLEOTIDE

PURINE Adenine

Adenosine

Adenylate

Deoxyadenosine

Deoxyadenylate

Guanosine

Guanylate

Deoxyguanosine

Deoxyguanylate

Guanine

NITROGENOUS BASES BASE

NUCLEOSIDE

NUCLEOTIDE

Cytidine

Cytidylate

Deoxycytidine

Deoxycyticylate

Thymidine Deoxythymidine

Thymidylate Deoxythymidylate

Uridine

Uridylate

PYRIMIDINE Cytosine

Thymine

Uracil

NUCLEIC ACID 5 End ’

PO4

3 5

CH2 O ’

A 1’

C PO4

CH2 O

Phosphodiester bond G PO4

CH2 O

3’

3’ End

DNA Double – helix Hydrogen bonding between nitrogenous bases 

  

Base pairs

Complementary strands Antiparallel Composed of a sugar- phosphate backbone Sugar is deoxyribose Chargaff Rule  The amount of adenine is equal to the amount of thymine  The amount of guanine is equal to the amount of cytosine

DNA 5’ End

3’ End

PO4

PO4

O N

H2C O 5’

H

N

T

N

A

N

H

N

3’ 1’

O

5’ O CH2

1’ 3’ PO4

PO4 N

N

H2C O 5’

C

N O

1’

H

O H H

N N

G

N

3’ 1’

O

5’ CH2

3’

3’ End

PO4

PO4

5’ End

RNA  

 

Usually single – stranded Sugar – phosphate backbone consists of ribonucleotides  Linked by 3’ – 5’ phosphodiester bond Sugar is ribose Nitrogenous base URACIL replaces THYMINE

RNA mRNA

tRNA

rRNA

Carrier of genetic information from DNA Direct synthesis of cellular proteins Polycistronic vs. monocistronic Activates amino acids Transports amino acids to ribosomes Adapter molecule

Provides the machinery for protein synthesis Prokaryotes – 70S Eukaryotes – 80S

3’ 5’

TψC loop

D loop

Anticodon loop

CHROMOSOME Stabilized by located

rRNA

Located in producing

Nucleus histones

Starts in

contains To form

DNA

chromatin

Template in

tRNA

produces

mRNA

Replication

Introns

Described as

S phase Of the

Cell Cycle

Transcription

undergoes

during

Semiconservative Initiated by

OriC

Ribosome

Promoter

Composed of

Exons

Site of Template in

Translation by

Polymerization producing

Results in

Elongation

Polypeptide