2919122
Proteins
usually very large molecules
each organism has
many different types of protein that differ from species to
species.
shape of one
protein differs from another.
very important in
living organisms
enzymes are a
group of proteins involved in almost
every living process, vast range of enzymes with diverse
range of functions.
structure of amino acids
monomers that join via polymerisation to form polypeptides
polypeptides combine to form proteins
Around 100 amino acids have been identified of which 20 occur
naturally in proteins
↳ these 20
provide evidence of evolution due to
occuring in all
living organisms.
Every amino acid has a central carbon, sometimes even called
alpha carbon, 4 groups attached.
to acidic
it opposite
1Amino
group (-NH2) a basic
group
2) Carboxyl group (C00H) acidic
group
3) Hydrogen atom (H)
4) R(side) group -
a
variety of different chemical
groups, each has a different R
group, provides variation naturally occuring, differ only in their R
group.
amino carboxyl H H
group group
H
H
Or W Or
R
I
I
10
H
I
N- -
I
R
C
-OH H C
C
H
MN--co
I
O O
Formation of a
peptide bond
similar to now carbs and lipids bond, is a condensation reaction
Amino acids bond to
can form dipeptides
water made
by combining an -on from carboxyl with-H from the amine
group.
become linked by bond
Then a
peptide
H-
H
H H
10 SF 11 H
N-s m-d c
( 1 0
c0
=
peptide
x
t MzO
/ c
->
- - -
cc -
-
+
OM
R p H "OH
bond
peptide
,29/9/22
protein structure
Primary structure
polypeptides have usually many of the different types of the 20 naturally occurring amino acids.
↳ this means there are an almost limitless number of combinations that make
up the primary structure.
The is acids bond
primary structure simply the sequence/order the amino together in.
the
primary structure determines the ultimate shape and hence function of each
protein.
Secondary structure
in which the forms
secondary structure is the shape polypeptide chain as a result of hydrogen bonding.
there I main in aphelix
are shapes secondary structures, an or a
p pleated sheet.
EE
Ih
C helix (most
commonly formed) B pleated sheet
either side
e.g
linked and
polypeptides posses-NH co
group on
H
the H on the -NH and OH on (=0 have positive and negative charge
2 P, I /8 =
N-c-c
Therefore they readily for weak
hydrogen bonds
b over all
negative
overall
positive
the bonds hold the structure in
hydrogen secondary place.
Tertiary structure
⑮
when due to bending and twisting of the
secondary structure of the c helix into accomplex structure
Disulfide, ionic and hydrogen bonding contribute to
maintaining tertiary structure
some
proteins only have to tertiary structures and can maintain them without quaternary structures.
up
Quaternary structure
when
multiple polypeptide chains combine with associated non
protein prosthetic groups to make large, complex
↳ molecules
e.g haemoglobin
Prosthetic molecule
Proteins
usually very large molecules
each organism has
many different types of protein that differ from species to
species.
shape of one
protein differs from another.
very important in
living organisms
enzymes are a
group of proteins involved in almost
every living process, vast range of enzymes with diverse
range of functions.
structure of amino acids
monomers that join via polymerisation to form polypeptides
polypeptides combine to form proteins
Around 100 amino acids have been identified of which 20 occur
naturally in proteins
↳ these 20
provide evidence of evolution due to
occuring in all
living organisms.
Every amino acid has a central carbon, sometimes even called
alpha carbon, 4 groups attached.
to acidic
it opposite
1Amino
group (-NH2) a basic
group
2) Carboxyl group (C00H) acidic
group
3) Hydrogen atom (H)
4) R(side) group -
a
variety of different chemical
groups, each has a different R
group, provides variation naturally occuring, differ only in their R
group.
amino carboxyl H H
group group
H
H
Or W Or
R
I
I
10
H
I
N- -
I
R
C
-OH H C
C
H
MN--co
I
O O
Formation of a
peptide bond
similar to now carbs and lipids bond, is a condensation reaction
Amino acids bond to
can form dipeptides
water made
by combining an -on from carboxyl with-H from the amine
group.
become linked by bond
Then a
peptide
H-
H
H H
10 SF 11 H
N-s m-d c
( 1 0
c0
=
peptide
x
t MzO
/ c
->
- - -
cc -
-
+
OM
R p H "OH
bond
peptide
,29/9/22
protein structure
Primary structure
polypeptides have usually many of the different types of the 20 naturally occurring amino acids.
↳ this means there are an almost limitless number of combinations that make
up the primary structure.
The is acids bond
primary structure simply the sequence/order the amino together in.
the
primary structure determines the ultimate shape and hence function of each
protein.
Secondary structure
in which the forms
secondary structure is the shape polypeptide chain as a result of hydrogen bonding.
there I main in aphelix
are shapes secondary structures, an or a
p pleated sheet.
EE
Ih
C helix (most
commonly formed) B pleated sheet
either side
e.g
linked and
polypeptides posses-NH co
group on
H
the H on the -NH and OH on (=0 have positive and negative charge
2 P, I /8 =
N-c-c
Therefore they readily for weak
hydrogen bonds
b over all
negative
overall
positive
the bonds hold the structure in
hydrogen secondary place.
Tertiary structure
⑮
when due to bending and twisting of the
secondary structure of the c helix into accomplex structure
Disulfide, ionic and hydrogen bonding contribute to
maintaining tertiary structure
some
proteins only have to tertiary structures and can maintain them without quaternary structures.
up
Quaternary structure
when
multiple polypeptide chains combine with associated non
protein prosthetic groups to make large, complex
↳ molecules
e.g haemoglobin
Prosthetic molecule
