Department of Chemistry

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• Department of Chemistry
• CHEM1020 General Chemistry
• Instructor Dr. Hong Zhang
• Foster Hall, Room 221
• Tel [phone]
• Email hzhang_at_tntech.edu

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CHEM1020/General Chemistry_______________________
__________________Chapter 15. (L16)-Biochemistry

• Todays Outline
• Nucleic acids
• types of nucleic acids DNA, RNA
• monomers of nucleic acids Nucleotides
• components of nucleotide monomers
• formation of DNA and RNA polymers
• base sequence in DNA and RNA
• Comparison between proteins and nucleic acids
  in terms of polymer chemistry

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Nucleic acids
• Present in cell, serving as (genetic)
  information and control center of the cell
• Two kinds of nucleic acids
• DNA deoxyribonucleic acid, blueprint for all
  the proteins of an organism
• found mainly in cell nucleus
• RNA ribonucleic acid, directing protein
  assembly (help to synthesize proteins)
• found in all parts of the cell

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Both DNA and RNA are long chain polymers
• Basic monomers for DNA and RNA
• The basic monomers are various kinds of
  nucleotides, or each monomer is a nucleotide
• Basic chemical components for the nucleotide
  monomers for DNA and RNA
• each nucleotide has three basic components
• -a pentose sugar (5 C ring, organic
  hydrocarbon)
• -a heterocyclic amine base (organic base)
• -a phosphate unit (inorganic unit)
• a nucleotide a phosphate a pentose a base

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Each nucleotide has three basic components
• -A pentose sugar (5 C ring, organic
  hydrocarbon)
• For DNA 2-Deoxyribose
• For RNA Ribose
• -A heterocyclic amine base (organic base)
• For DNA
• Guanine (G), Cytosine (C), Adenine (A),
  Thymine(T)
• For RNA
• Guanine (G), Cytosine (C), Adenine (A), Uracil
  (U)
• -A phosphate unit (inorganic unit)
• For both DNA and RNA PO43- anion (Pi)

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Each nucleotide has three basic components
• -Pentose sugars, 5 C ring, organic hydrocarbon
• ..For DNA 2-Deoxyribose
• the O from the OH on 2-C is lost, only H
  present (deoxydized, reduced)
• ..For RNA Ribose
• The -OH on 2-C is present
• How to tell if a nucleic acid is a DNA or an
  RNA?
• Check the 2-C to see if only H is there or OH
  is there.

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Each nucleotide has three basic components
• -Heterocyclic amine bases (organic base)
• For DNA Guanine, Cytosine, Adenine, Thymine
• For RNA Guanine, Cytosine, Adenine, Uracil
• Adenine and Guanine have two fused rings,
  classified as pruines
• Cytosine, thymine, and uracil have only one
  ring
• classified as primidines
• The five bases behave as bases because they all
  have amine groups, which are basic.
• -Difference between thymine and uracil
• thymine has a -CH3 group in its base ring, but
  uracil does not.

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Structure of nucleotides
• Each nucleotide is composed of a sugar with two
  side components, a phosphate and an organic base
• .Linkage between the phosphate and the sugar
• phosphate ester linkage between Pi and C-5
  formed by condensation through elimination of H
  from phosphate and the OH group on C-5 of the
  sugar
• .Linkage between base and sugar
• ß-glycosidic bond (glycoside linkage) between
  the N of the base and C-1 formed by
  condensation through elimination of the H from
  the N on the base and OH from the C-1 on the
  sugar

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Structure of nucleotides
• General formula for nucleotide monomers
• base
• Pi-sugar
• Example Adenosine monophosphate (AMP)
• adenine
• Pi-sugar
• Nucleotides differ because of their different
  bases, much as amino acids differ because of
  their R groups.

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Chapter 15. (L16)-Biochemistry

• Nucleic acids
• Structure of nucleotide polymers, i.e., nucleic
  acids
• General formula for nucleotide polymers
• base base base base
  base
• 
  
• -Pi-sugar-Pi-sugar-Pi-sugar-Pi-sugar-Pi-sugar-
• Linkage between two nucleotide monomers
• phosphate ester linkage formed by condensation
  between the OH of the phosphate and the OH on
  C-3

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Chapter 15. (L16)-Biochemistry

• Sequence of bases in nucleic acids
• The sequence of bases in nucleic acids are
  highly important, which carries the genetic
  information.
• The four bases for DNA
• G, C, A, T, or GCAT, only four letters, but
  these can form various combinations like various
  words or sentences in DNA, thus carrying various
  bioinformation.

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Chapter 15. (L16)-Biochemistry

• Polymer chemistry of proteins and nucleic acids
• Comparison between proteins and nucleic acids
  in their polymer chemistry
• Item Protein Nucleic Acid
• monomers amino acids nucleotides
• sequence component -R in AA base in nucleotide
• monomer linkage amide phosphate ester
• 1st level structure AA sequence base sequence
• 2nd level structure a-helix double-helix (DH)
• 3rd level structure helix folding DH strand
  folding
• 4th level structure complicated complicated

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• Homework Make up three quiz practice questions
  with four choices regarding this lecture (L16),
  due Feb. 28 (M).
• (a)
• (b)
• (c)
• (d) .

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The two general kinds of nucleic acids are
• (a) DAN and RAN
• (b) DDT and PCB
• (c) DNA and RNA
• (d) none of above.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• DNA and RNA are shout-cuts in biochemistry
  respectively for
• (a) deoxyribonucleic alcohol and ribonucleic
  alcohol
• (b) deoxyribonucleic acid and ribonucleic acid
• (c) definitely not applicable and relatively not
  applicable
• (d) none of above.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• In a cell, DNA and RNA are present, respectively
• (a) in all parts of the cell for DNA and mainly
  in cell nucleus for RNA
• (b) mainly in cell nucleus for both DNA and RNA
  
• (c) all parts of cell for both DNA and RNA
• (d) mainly in cell nucleus for DNA and found in
  all parts of the cell for RNA.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The major biological functions of DNA are
• (a) having fun in the cell
• (b) directing and facilitating synthesizing
  proteins
• (c) carrying the genetic information and serving
  as the blueprint for all the proteins of an
  organism
• (d) controlling the temperature of the living
  thing.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The major biological functions of RNA are
• (a) having fun in the cell
• (b) directing and facilitating synthesizing
  proteins
• (c) carrying the genetic information and serving
  as the blueprint for all the proteins of an
  organism
• (d) controlling the temperature of the living
  thing.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• Both DNA and RNA are
• (a) large inorganic molecules
• (b) small biochemical molecules
• (c) biochemical monomers
• (d) biochemical polymers.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The monomers for DNA and RNA are
• (a) monosaccharides
• (b) nuclear particles
• (c) nucleic acids
• (d) nucleotides.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• A nucleotide has three basic chemical
  components, which are
• (a) a 5 carbon ring sugar, an organic base, and
  an inorganic sulfate
• (b) a 5 carbon ring sugar, an organic base, and
  an inorganic phosphate
• (c) a 5 carbon ring alkane, an organic base, and
  an inorganic phosphate
• (d) a 5 carbon ring sugar, an inorganic base,
  and an inorganic phosphate.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The 5 carbon ring sugar for DNA is
• (a) fructose
• (b) glucose
• (c) ribose
• (d) 2-deoxyribose.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The 5 carbon ring sugar for RNA is
• (a) fructose
• (b) glucose
• (c) ribose
• (d) 2-deoxyribose.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The difference between ribose and deoxyribose is
  that
• (a) the deoxyribose does not have the COOH
  group on its C-2 carbon while ribose has
• (b) the deoxyribose has the OH group on its C-2
  carbon, while the ribose does not
• (c) the deoxyribose does not have the OH group
  on its C-2 carbon, while the ribose has
• (d) none of above.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The four organic bases for DNA nucleotides are
• (a) guanine, adenine, thymine, and uracil
• or G, A, T, U
• (b) guanine, cytosine, adenine, and thymine,
• or G, C, A, T
• (c) guanine, cytosine, adenine, and uracil
• or G, C, A, U
• (d) none of above.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The four organic bases for RNA nucleotides are
• (a) guanine, adenine, thymine, and uracil
• or G, A, T, U
• (b) guanine, cytosine, adenine, and thymine,
• or G, C, A, T
• (c) guanine, cytosine, adenine, and uracil
• or G, C, A, U
• (d) none of above.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• A DNA nucleotide or an RNA nucleotide is formed
  by the three units of sugar, base, and phosphate
  in the way of
• (a) the sugar connects to the base and the base
  connects to the phosphate, i.e. sugar-base-Pi
• (b) the sugar connects to the phosphate and the
  phosphate connects to the base, i.e.
  sugar-Pi-base
• (c) the sugar connects to the phosphate on one
  position of the sugar ring and to the base on
  another position of the sugar ring, i.e.
  Pisugar-base
• (d) none of above.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• DNA nucleotides or RNA nucleotides differ by
• (a) the sugars in the nucleotides
• (b) the bases in the nucleotides
• (c) the phosphate in the nucleotides
• (d) none of above.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• A DNA or an RNA is formed by which
  polymerization reaction?
• (a) addition polymerization
• (b) condensation polymerization
• (c) hydrogen bonding polymerization
• (d) ionic bonding polymerization.

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Chapter 15. (L16)-Biochemistry

• Quiz Time
• The general schematic formula for a DNA or an
  RNA is
• (a) base-sugar-Pi-base-sugar-Pi-base-sugar-Pi-
  
• (b) Pi Pi
  Pi
• 
  
• -base-sugar-base-sugar-base-sugar-
• (c) base base base base
• 
  
• -Pi-sugar-Pi-sugar-Pi-sugar-Pi-sugar-
• (d) none of above.