Download Protein Folding Lab with Balloons

Name_______________________________________________________________________
Protein Folding Lab with Balloons
Objective: I can create a protein model based on characteristics of amino acids.
DNA codes for RNA which codes for the order of amino acids to make specific proteins. A
protein’s structure determines its function. Since different amino acids have different properties,
they influence the folding of the protein. Some amino acids are hydrophobic, some polar, and
others ionic ( + or -). The resulting structure enables the specific protein to interact with other
molecules in the cell and/or body.
Each amino acid consists of carbon from which are attached an amino group, a carboxyl group
and a side group. The side groups (chains) are what vary from amino acid to amino acid. In this
very simplistic lab we will represent various amino acids with comparatively long and short side
chains with long and short balloons. Each balloon must be labeled as to which amino acid it is,
charges (if there are any), or if it is hydrophobic. The peptide bonds will be six inches long and
made of string. Your objective is to assemble the amino acids in the order coded for by DNA
below, joining them together with the string peptide bonds, and folding the resulting protein
molecule according to the affinity of amino acids.
Directions: Answer the following in your lab notebook.
1. Define the following words: polar, hydrophobic, ions
2. Copy and complete the chart below:
DNA:
ATA
CAT
TTT
GTA
TCG
ATT
mRNA:
__________________________________________________
tRNA:
__________________________________________________
Amino Acids: __________________________________________________
Balloon Type: __________________________________________________
AA Properties:__________________________________________________
3. What will happen to the resulting protein and its function if a single base pair in the DNA
sequence were to change? For example, if ATA changed to AAA. Your explanation should
include the words mRNA, tRNA, amino acid, and final protein structure.
4. Given that there are only so many amino acids (20), why are there so many different types of
proteins (hundreds of thousands)?
Name_______________________________________________________________________
Amino Acids for mRNA
codons
codons
Second Base Codon
A
G
U
C
lysine
lysine
asparagine
asparagine
glutamic acid
glutamic acid
aspartic acid
aspartic acid
STOP
STOP
tyrosine
tyrosine
glutamine
glutamine
histidine
histidine
arginine
arginine
serine
serine
glycine
glycine
glycine
glycine
STOP
tryptophan
cysteine
cysteine
arginine
arginine
arginine
arginine
U
C
isoleucine
methionine
isoleucine
isoleucine
valine
valine
valine
valine
leucine
leucine
phenylalanine
phenylalanine
leucine
leucine
leucine
leucine
threonin
threonin
threonin
threonin
alanine
alanine
alanine
alanine
serine
serine
serine
serine
proline
proline
proline
proline
Properties of certain amino acids
Short
Glutamic Acid (Glu)
Aspartic Acid (Asp)
Serine (Ser)
Threonine (Thr)
Valine (Val)
Long
(-)
(-)
polar
polar
hydrophobic
Arginine (Arg)
Lysine (Lys)
Tyrosine (Tyr)
Histidine (His)
Phenylalanine (Phe)
Methionine (Met)
Leucine (Leu)
Isoleucine (Ile)
(+)
(+)
polar
polar
hydrophobic
hydrophobic
hydrophobic
hydrophobic
A
G
U
C
A
G
U
C
A
G
U
C
A
G
U
C
Third Base in Codon
First base in code
A
G