Transcript 1 Components Nucleic Acids

Lecture Presentation
Chapter 21
Nucleic Acids and
Protein Synthesis
Karen C. Timberlake
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Chapter 21
Nucleic Acids and Protein Synthesis
A histology technician studies
the microscopic make-up of
tissues, cells, and bodily fluids
with the purpose of detecting
and identifying the presence
of a specific disease.
They determine blood types
and the concentrations of
drugs and other substances
in the blood.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Chapter Readiness
Core Chemistry Skills
• Forming Amides (18.5)
• Drawing the Zwitterion for an Amino Acid (19.1)
• Identifying the Primary, Secondary, Tertiary, and
Quaternary Structures of Proteins (19.4, 19.5)
• Identifying Factors Affecting Enzyme Activity (20.3)
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
21.1 Components of Nucleic Acids
The general structure
of a nucleotide
includes a
• nitrogen-containing
base.
• sugar.
• phosphate group.
Learning Goal Describe the bases and ribose sugars that
make up the nucleic acids DNA and RNA.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Nucleic Acids
There are two types of nucleic acids:
• deoxyribonucleic acid (DNA), which may contain
several million nucleotides, and ribonucleic acid (RNA),
which may contain several thousand nucleotides.
• both are unbranched polymers of repeating monomer
units known as nucleotides.
Each nucleotide has three components:
• a base that contains nitrogen.
• a five-carbon sugar.
• a phosphate group.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Bases
The bases in DNA and RNA are
• derivatives of the heterocyclic amines pyrimidine or purine.
• pyrimidines with a single ring containing two nitrogen atoms.
• purines with two rings, each containing two nitrogen atoms.
• H+ acceptors at the nitrogen atoms in each base.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Bases in DNA
In DNA,
• the purine bases
with double rings
are adenine (A) and
guanine (G).
• the pyrimidine
bases with single
rings are cytosine
(C) and thymine (T).
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Bases in RNA
In RNA,
• the purine bases
with double rings
are adenine (A) and
guanine (G).
• the pyrimidine
bases with single
rings are cytosine
(C) and uracil (U).
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Pentose Sugars
The five-carbon sugar
• in RNA is ribose.
• in DNA is deoxyribose,
with no O atom on C2′.
• has carbon atoms
numbered with primes
to distinguish them from
the atoms in the bases.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Nucleosides
A nucleoside
• is composed of a nitrogen-containing base and a sugar, either ribose
or deoxyribose.
• has a base linked by a β-N-glycosidic bond to C1′ of a sugar (ribose
or deoxyribose).
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Nucleotides
• A nucleotide has a phosphate group attached to the C5′
— OH group of a nucleoside.
• The addition of a phosphate to a nucleoside forms a
nucleotide.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Nucleotides of DNA and RNA
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Summary of the Components in DNA and RNA
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Naming Nucleosides and Nucleotides
• The name of a nucleoside that contains a purine
ends with osine.
• The name of a nucleoside that contains a
pyrimidine ends with idine.
• The names of DNA nucleosides add deoxy to the
beginning of their names.
• The corresponding nucleotides in RNA and DNA
are named by adding monophosphate to the end
of the nucleoside name.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
RNA, DNA Nucleosides and Nucleotides
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
AMP, ADP, and ATP
• Adding a phosphate group to AMP forms the diphosphate, ADP.
• Adding a phosphate group to ADP forms the triphosphate, ATP.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Study Check
Give the name and abbreviation for the following
molecule, and list its base and sugar:
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Solution
Give the name and abbreviation for the following
molecule, and list its base and sugar:
Guanosine monophosphate (GMP)
Base: guanine
Sugar: ribose
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.