NUCLEOSIDES

• Comprise a sugar and a base

NUCLEOTIDES

• Phosphorylated nucleosides (at least one phosphorus group)
• Link in chains to form polymers called nucleic acids (i.e. DNA and RNA)

N-BETA-GLYCOSIDIC BOND

• Links nitrogenous base to sugar in nucleotides and nucleosides
• Purines: C1 of sugar bonds with N9 of base
• Pyrimidines: C1 of sugar bonds with N1 of base

PHOSPHOESTER BOND

• Links C3 or C5 hydroxyl group of sugar to phosphate

NITROGENOUS BASES

• Adenine
• Guanine
• Cytosine
• Thymine (DNA)
• Uracil (RNA)

NUCLEOSIDES

• =sugar + base
• Adenosine
• Guanosine
• Cytidine
• Thymidine
• Uridine

NUCLEOTIDE MONOPHOSPHATES – ADD SUFFIX ‘SYLATE’

• = nucleoside + 1 phosphate group
• Adenylate
• Guanylate
• Cytidylate
• Thymidylate
• Uridylate

Add prefix ‘deoxy’ when the ribose is a deoxyribose: lacks a hydroxyl group at C2.

• Thymine only exists in DNA (deoxy prefix unnecessary for this reason)
• Uracil only exists in RNA

NUCLEIC ACIDS (DNA AND RNA)

• Phosphodiester bonds: a phosphate group attached to C5 of one sugar bonds with
  -OH group on C3 of next sugar
• Nucleotide monomers of nucleic acids exist as triphosphates
• Nucleotide polymers (i.e. nucleic acids) are monophosphates
• 5′ end is free phosphate group attached to C5
• 3′ end is free -OH group attached to C3