Lecture 2 Feb 10 Flashcards
What is the monomer of a protein?
Amino Acids
What is the polymer?
Polypeptide
What is the covalent bond for proteins?
Peptides
What are amino acids?
They are organic molecules with amino and carboxyl groups
What causes amino acids to differ?
R group side chains
How many amino acids are there?
20 total
Basic Amino acids have what charge?
Positive charge
Acidic Amino acids have what charge?
Negative charge
What is the key component of non polar side chains?
Hydrocarbon structure/bonds
What is key component of polar side chains?
Most contain oxygen or more electronegative molecules
What is range in length of polypeptides?
few to >1000; each have unique linear sequence of amino acids
What are the four levels of protein structure?
Primary, secondary, tertiary, quaternary
What is a primary structure of proteins?
unique sequence of amino acids (polypeptide chain)
What is a secondary structure of proteins?
coils and folds in polypeptide chain; result of hydrogen bonds on repeating constituents on backbone
What is tertiary structure of proteins?
determined by interactions among various side chains; overall shape of polypeptide is caused by these interactions
What is Quaternary structure of proteins?
overall protein structure consisting of multiple polypeptide chains
What is an alpha helix?
H bond every 4th peptide bond
* Very common in proteins across membranes
What is a Beta Pleated sheet?
typically 3-10 amino acids, need two or more strands, parallel or anti-parallel
What is an ionic?
Attraction between cation and anion; acidic/basic R groups
What are Van Der Waals interactions?
attractions between molecules that are close together as result uneven distribution in molecule
What is a di-sulfide bridge?
Covalent bonds between cysteine, stabilize protein structure by being close together at the bending of the protein
Examples of physical and chemical conditions impacting protein structure
pH, salt concentration, temperature, solvent
Examples of changing primary structure
Change in primary structure can affect protein’s structure→function
What is sickle cell disease?
ONE aa substitution in hemoglobin in the 6th slot in chain
Abnormal hemoglobin cause RBCs to aggregate into chains and deform into a sickle shape; this shape can clog blood vessels and impede blood flow