Protein

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Protein 18 of the stuff in a cell is
protein Comprised of the elements C H O N Some
amino acids / proteins also contain S P
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• Proteins are very large molecules

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Proteins are very large molecules The protein
zian found in corn has the formula
C736H1161N184O208S3 Compare that to glucose!
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• Proteins are very large molecules
• The protein zian found in corn has the formula
  C736H1161N184O208S3
• Compare that to glucose!
• They have a 3 dimensional shape

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Proteins are very large molecules The protein
zian found in corn has the formula
C736H1161N184O208S3 Compare that to
glucose! They have a 3 dimensional shape
this is extremely important in how a protein
functions
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Monomer Polymer Amino Acid
Protein Polypeptide
20 different amino acids the type, order and
number of amino acids determine the protein
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There are 20 different amino acids needed for the
formation of essential proteins 9 of which we
need to get from our diet
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An Amino Acid is comprised of
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An Amino Acid is comprised of An amino group
H2N
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An Amino Acid is comprised of An amino
group A carboxyl group
H2N COOH
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An Amino Acid is comprised of An amino
group A carboxyl group An R group
H2N COOH
R
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H2N COOH
R
Amino Acid
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H2N COOH
H2N
COOH
R
R
R
Peptide Bonds
Amino Acid
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3
1
2
H2N COOH
H2N
COOH
R
R
R
3 or more amino acids form a polypeptide or
protein
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H2N COOH
H2N
COOH
R
R
R
What makes an amino acid different is its R group
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H2N COOH
H2N
COOH
R
R
R
What makes an amino acid different is its R group
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H2N COOH
H2N
COOH
R
R
R
What makes an amino acid different is its R group
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H2N COOH
H2N
COOH
R
R
R
What makes an amino acid different is its R group
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1. The order of amino acids in the polypeptide
chain is called the Primary Structure
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• The order of amino acids in the polypeptide chain
  is called
• the Primary Structure
• 2. The Secondary Structure is the way that chain
  is arranged

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• 1. The order of amino acids in the polypeptide
  chain is called the Primary Structure
• 2. The Secondary Structure is the way that chain
  is arranged
• Polypeptide chains can be arranged three ways
• a (alpha) - coiled in a helix like a spring
• ß (beta) in pleated sheets
• Random in ways dissimilar to a and ß
• (thats really clear isnt it?)

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a helix note the Liaison H
Its French for yogurt, I mean H-bonds
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ß pleated sheet
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Polypeptide chain
Hydrogen Bonds


ß pleated sheet
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1. The order of amino acids in the polypeptide
chain is called the Primary Structure 2. The
Secondary Structure is the way that chain is
arranged 3. The Tertiary Structure is the 3
dimensional shape the polypeptide forms when
completed
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1. The order of amino acids in the polypeptide
chain is called the Primary Structure 2. The
Secondary Structure is the way that chain is
arranged 3. The Tertiary Structure is the 3
dimensional shape the polypeptide forms when
completed 4. The Quaternary Structure describes
a 3 dimensional structure made up of two or more
polypeptide chains
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ie several tertiary structure polypeptides
joined together
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The proteins we have considered up until now are
simple proteins They contain ONLY amino acids
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The proteins we have considered up until now are
simple proteins They contain ONLY amino
acids Conjugated Proteins Conjugated proteins
are proteins where the amino acid chains
conjugate (join) with other groups
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The proteins we have considered up until now are
simple proteins They contain ONLY amino
acids Conjugated Proteins Conjugated proteins
are proteins where the amino acid chains
conjugate (join) with other groups A protein
Haem group haemoglobin
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The proteins we have considered up until now are
simple proteins They contain ONLY amino
acids Conjugated Proteins Conjugated proteins
are proteins where the amino acid chains
conjugate (join) with other groups A protein
Haem group haemoglobin A protein
nucleic acid group nucleoprotein
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The proteins we have considered up until now are
simple proteins They contain ONLY amino
acids Conjugated Proteins Conjugated proteins
are proteins where the amino acid chains
conjugate (join) with other groups A protein
Haem group haemoglobin A protein
nucleic acid group nucleoprotein These
molecules are often found in the nucleus
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Haemoglobin is a conjugated protein.
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Haemoglobin is a conjugated protein. The
quaternary structure of a haemoglobin molecule is
consists of four tertiary structure proteins
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Haemoglobin is a conjugated protein. The
quaternary structure of a haemoglobin molecule is
consists of four tertiary structure proteins -
two a chains and two ß chains -
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Haemoglobin is a conjugated protein. The
quaternary structure of a haemoglobin molecule is
consists of four tertiary structure proteins -
two a chains and two ß chains - with a Haem group
attached to each
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Haemoglobin is a conjugated protein. The
quaternary structure of a haemoglobin molecule is
consists of four tertiary structure proteins -
two a chains and two ß chains - with a Haem group
attached to each
Tertiary structure protein
Haem group
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Haemoglobin is a conjugated protein. The
quaternary structure of a haemoglobin molecule is
consists of four tertiary structure proteins -
two a chains and two ß chains - with a Haem group
attached to each Get your head around this
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Haemoglobin is a conjugated protein. The
quaternary structure of a haemoglobin molecule is
consists of four tertiary structure proteins -
two a chains and two ß chains - with a Haem group
attached to each Get your head around this A
red blood cell has 250 million molecules of
haemoglobin
250,000,000
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Haemoglobin is a conjugated protein. The
quaternary structure of a haemoglobin molecule is
consists of four tertiary structure proteins -
two a chains and two ß chains - with a Haem group
attached to each Get your head around this A
red blood cell has 250 million molecules of
haemoglobin Each haemoglobin molecule is made of
four tertiary structure proteins - two a chains
and two ß chains
250,000,000 X 4 1,000,000,000
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• Haemoglobin is a conjugated protein.
• The quaternary structure of a haemoglobin
  molecule is consists of four tertiary structure
  proteins
• - two a chains and two ß chains -
• with a Haem group attached to each
• Get your head around this
• A red blood cell has 250 million molecules of
  haemoglobin
• Each haemoglobin molecule is made of four
  tertiary structure proteins
• two a chains and two ß chains
• Your body makes 200 billion new red blood cells a
  day

250,000,000 X 4 1,000,000,000 X
200,000,000,000
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200,000,000,000,000,000,000 new proteins
synthesised just for red blood cells
EVERYDAY!!!
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Thats it for proteins, for now