Chapter (1) lecture 2 - Proteins Part (1) Flashcards
(29 cards)
What is the main idea of CYStine?
Cysteine—the most reactive amino acid—can form disulfide-bonded cysteine.
What is the most reactive amino acid?
Cysteine
Why is cysteine so important?
It can form disulfate-bonded cysteine.
Amino acids can be held together by _ amide bonds called _.
Amino acids can be held together by amide bonds called peptide bonds.
Biological polypeptides are divided into_ and , depending on their.
Biological polypeptides are divided into peptides and proteins, depending on their length.
Protein _ structure is the sequence of _.
Protein primary structure is the sequence of amino acids.
What are the two most common types of protein secondary structures called?
Alpha Helix
Beata strand sheet.
What is the dimensional arrangement of the protein that has a tertiary structure?
Three-dimensional arrangement of the molecule in space.
_ interactions hold the tertiary structure together
Non-local interactions
Protein quaternary structure has some proteins and involves the association of more than one _ structure into the _.
Protein quaternary structure—which some proteins have—involves the association of more than one tertiary
structure into the functional protein
Large quaternary complexes can create _.
fibrous proteins
What two methods destroy protein function?
- Denaturation
- Aggregation
Name the five protein roles?
- Enzymes - The proteins that catalyze specific chemical reactions in a bio-system.
- Structure
- Transport
- Binding
- Signaling - Gulcogon and Inslion
EL Camino Rymes with _ amino
Only the _ amino acids are found in proteins
Only L amino acids are found in proteins.
In a L Isomer What are the two charges that NH2 and NH3+ be?
They can be NH2 neutral or NH3+ Postive
In a L isomer what is the charge on the COOH?
Can be COO-; negative or COOH neutral
Ionization of Amino acids are a fuction of _.
pH
When pH=Pka of an ionizable group, the group would be what percentage protoated?
50%
When pH< Pka of an ionizable group, the group would be what percentage protoated?
The group will be more protonated.
When pH > Pka of an ionizable group, the group would be what percentage protoated?
The group will be more deprotonated.
What is a Zitterion?
Contains only a postive and negative ion.
How is the isoelectic point of a moleclue found.
It is found where the Zwitterion that has a postive and negative ion and whatever the pH happens to be will be the isolelctic point of that molecule.
A carboxyl group ( coo-) has a pka of ~ _.
2ish
The Amino group (NH3+) has a pka of _.
9ish
