Theme 2C Flashcards
(59 cards)
Where are peptide bonds found, how are they formed
Between the amino and carboxyl group
Formed through dehydration reaction between amino and carboxyl
What is an amino acid?
They contain amino groups, carboxyl groups, R groups on a central carbon with a hydrogen
What is a polypeptide?
A linear chain of amino acids linked by peptide bonds does not include R groups
What are the classes of amino acids? What are the special functional amino acids
Nonpolar
Uncharged polar
Charged amino acids
Aromatic amino acid
Methionine
Proline
Cysteine
What is a nonpolar amino acids?
It’s R group usually has CH2 or CH3
What is an uncharged polar amino acid?
It’s R group usually has oxygen or OH
What is a charged amino acid?
It has r groups that contain acids or bases that can ionize
What is an aromatic amino acid?
R groups have a carbon ring with alternating single and double bonds
What is methionine
First amino acid in a polypeptide always
What is proline
Causes a kink in the polypeptide chains
This makes the 3-D structure because of the bend
What is cysteine
It is a disulfide bridge that contributes to the overall structure of polypeptides (s-s)
Only one that has sulphide bond
What is the primary amino acid sequence and why is it important
It determines the protein folding and 3-D structure, which is critical for the proper function of the protien, so is the primary protien structure
What is the secondary protein structure?
The structure depends on hydrogen bonding in the polypeptide backbone
Either comes as alpha helicis, which are ribbons or beta sheets, which are flat paper like
What is the tertiary proteins structure?
The 3-D structure of a single polypeptide formed by interactions between amino acid side chains, includes R groups
What is the quaternary structure of a protein?
Interactions between more than one polypeptide to form a multi subunit proteins.
Example is hemoglobin, which has two alpha helices, and two beta sheets.
How is protein folding disrupted?
Buy denaturation (heat, or chemicals) causes loss of function
Or mutations that change the amino acid sequence
How do chaperones help proteins?
Protect slow folding, or denatured proteins by preventing their aggregation (meaning sticking together and forming masses) (help proteins fold)
What are diseases associated with misfolded proteins?
Alzheimer’s (plagues of protein) Parkinson’s and creutzfeldt-Jakob
What are tRNAs
Adaptors between codons and amino acids
The molecule that is between the processes of going from mRNA to amino acid
Bridge between nucleotide and amino acid
What does the 2D and 3D shape of TRNA look like
Cloverleaf
L shape
Where did the amino acid attach to on the tRNA , what end!@?
tha acceptor stem which is at the 3’ end of the TRNA
What is the sequence of the acceptor stem (3’ end) in tRNA
5’-CCA-3’
Where and what is the anticodon in TRNA
The bottom loop
It has a three nucleotide sequence that recognizes the mRNA codon and base pairs with it
What direction is the anticodon pairing with the mRNA?
Antiparallel
If mRNA is 5-3
tRNA is 3-5