Transcript Protein Structure

Mr. Gibson – Advanced Science- Biochemistry Spring
2011
w/o January 31st
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
1.
2.
3.
4.
5.
6.
7.
Peptide Bond:
Primary Structure
Secondary Structure
Tertiary Structure
Quaternary Structure
Protein Stability
Protein Folding
Gif animation web-site source: http://www.tulane.edu
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Peptide Bond:
In your own words --can you state what a
peptide bond is?
And; what is the “waste
product” that results
from Peptide
bonding?
1.
?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Peptide Bond:
A covalent bond
between the
“carboxyl” group
(COOH) of one
amino acid (AA) and
the “amine” group
(NH) of another (AA)
1.
Waste product: water
Gif animation web-site source: http://www.tulane.edu
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Primary Structure
for Protein(s):
Again --- in your own
words, this would
be?
2.
?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Primary Structure
for Protein(s):
Simply put – a “linear
sequence” (putting
together in a
straight line) of
amino acids (all lefthanded) joined
together by peptide
bonds.
2.
Gif animation web-site source: http://www.tulane.edu
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Secondary Structure
for Protein(s):
Again --- in your own
words, this would
be?
3.
?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Secondary Structure
for Protein(s):
Refers to the regular
folding of regions of
the polypeptide
chain (primary
structure) held in
place by “hydrogen”
bonding.
3.
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Secondary Structure
for Protein(s):
Refers to the regular
folding of regions of
the polypeptide
chain (primary
structure) held in
place by “hydrogen”
bonding.
3.
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
3.
Secondary Structure
for Protein(s):
Notice the
“hydrogen bonds”
that lock these two
secondary structures
into place.
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Secondary Structure
for Protein(s):
Also; be aware of the fact
the “R” groups of the
AA residues are
always pointed
outward from the
secondary structures
that are formed (not
shown here).
3.
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Secondary Structure
for Protein(s):
Also; be aware of the fact
the “R” groups of the
AA residues are
always pointed
outward from the
secondary structures
that are formed .
3.
“R” groups pointing
outward in this alpha
helix secondary structure
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
4. Tertiary Structure
for Protein(s):
Again --- in your own
words, this would
be?
?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
4. Tertiary Structure
for Protein(s):
Refers to the 3-D
arrangement of all
the amino acids in a
peptide chain made
biologically active
“native”
conformation – by
multiple covalent
bonds (usually a
single protein
structural unit)?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
Quaternary
Structure for
Protein(s):
Again --- in your own
words, this would
be?
5.
?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
5.
Quaternary Structure
for Protein(s):
A protein made up of
MORE than ONE
polypeptide chain. This
refers to the spatial
arrangement of the
subunits and the
interactions between
those subunits.
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
6. Protein Stability:
Now, given what you
know already about
the structures of
proteins… what
makes them & what
holds them folded a
certain way…
Can you think of what
might keep these
structures STABLE?
?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
6.
Protein Stability:
Besides the peptide
bonds holding AA
residues together; it is
a combination of
hydrogen bonds &
other interactions
between the “R” groups
that stick out… that
provides stability to a
proteins’ structure.
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
7.
Protein Folding:
?
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
7. Protein Folding:
Proteins fold
spontaneously into
their “native”
conformation (shape)
with the PRIMARY
peptide structure
dictating the 3-D
structure.
Protein Structure
Biochemistry –
w/o January 31st
Key Notes
7. Protein Folding:
Protein folding is also
driven by:
a) Hydrophobic forces;
b) Ordered (specified)
set “pathways”;
c) “Accessory” proteins
called “isomerases”
and;
d) Molecular/protein
“chaperones”.