3.3 Amino Acids, Proteins, and DNA Flashcards
What is a dipeptide?
A dipeptide is formed from two amino acids joined by a peptide bond.
What is a tripeptide?
A tripeptide is formed when a dipeptide reacts with another amino acid.
What is the primary structure of a protein?
The specific sequence of amino acids held together by peptide bonds.
What type of bond holds the secondary structure of proteins?
Hydrogen bonds.
What attractions contribute to tertiary protein structure?
Tertiary structure is held by:
* Disulfide bridges
* Ionic attractions
* Hydrogen bonds.
What is a zwitterion?
A zwitterion is a molecule that has both positive and negative charges but is overall neutral.
What is the by-product of a condensation reaction when forming a peptide?
Water (H2O).
What is the strongest bond that can be found within a protein’s tertiary structure?
Disulfide bridges.
True or False: Only L-alanine occurs naturally.
True.
What is the active site of an enzyme?
The unique shape region of an enzyme where substrate molecules bind.
What is the lock and key hypothesis?
The model describing how specific substrates fit into the active site of enzymes.
Fill in the blank: Enzymes are typically ______ proteins.
globular.
What happens to an enzyme’s active site when temperature increases?
The active site shape can change, preventing substrate binding.
What are the complementary base pairs in DNA?
Adenine (A) pairs with Thymine (T) and Guanine (G) pairs with Cytosine (C).
How many hydrogen bonds are formed between A and T?
2 hydrogen bonds.
How many hydrogen bonds are formed between G and C?
3 hydrogen bonds.
What is the structure of cisplatin?
Cisplatin has a central platinum atom bonded to two chloride ligands and two ammonia ligands.
What is the main action of cisplatin in cancer treatment?
Cisplatin binds to guanine bases in DNA, preventing replication.
What are the adverse effects of cisplatin?
Cisplatin can cause hair loss and affect healthy cells, leading to side effects.
Fill in the blank: The sugar found within DNA is a ______ sugar.
pentose.
What is the function of superoxide dismutase?
To catalyze the dismutation of superoxide into oxygen and hydrogen peroxide.
What is the role of nitrogenase?
To catalyze the conversion of atmospheric nitrogen into ammonia.
What is the significance of the amino acid serine in biochemical reactions?
Serine can react with acids and bases and can form a zwitterion.
What is the term for molecules that inhibit enzyme activity?
Enzyme inhibitors.
What is the role of computational chemistry in drug development?
To simulate interactions of enzymes and drug candidates using mathematics and algorithms.
What is the nature of attractions that can form between an inhibitor and an enzyme?
Ionic and hydrogen bonds, among others.
How does pH affect enzyme function?
Altering pH changes the charges of groups within the enzyme, affecting bonding and active site shape.
How are nucleotides formed?
From a phosphate, 2-deoxyribose, and a base.
What is the shape and bond angle in cisplatin?
Cisplatin has a square planar shape.
What are the four different bases that could be attached to a nucleotide?
Adenine (A), Cytosine (C), Guanine (G), Thymine (T).
