Proteins - CHEM 17 (LEC)

These flashcards cover key concepts, definitions, and terms related to amino acids, proteins, and enzymes as discussed in the lecture.

Hemoglobin

A protein that transports oxygen in the blood.

Sickle-cell anemia

A disease resulting from a defective form of hemoglobin, leading to crescent-shaped red blood cells.

Amino acids

Building blocks of proteins, with 20 common types in human proteins.

Protein

Large biological molecules made of amino acids that perform various functions in living organisms.

Primary structure

The specific sequence of amino acids in a polypeptide chain.

Secondary structure

Protein structure formed by hydrogen bonds between peptide bonds, including alpha helices and beta-pleated sheets.

Tertiary structure

The three-dimensional shape of a protein determined by interactions between R groups of amino acids.

Quaternary structure

Structural level formed when two or more polypeptide chains combine to form a biologically active protein.

Enzyme

A protein that acts as a biological catalyst to accelerate chemical reactions.

Active site

The region of an enzyme where substrate binds and catalysis occurs.

Denaturation

The process where proteins lose their structural integrity and biological activity due to environmental changes.

Competitive inhibitor

A substance that competes with the substrate for binding at the active site of an enzyme.

Noncompetitive inhibitor

A substance that binds to an enzyme at a site other than the active site, altering the enzyme's shape.

Irreversible inhibitor

A substance that permanently inactivates an enzyme by forming a covalent bond with it.

Electrophoresis

A laboratory technique used to separate proteins based on their charge and size, often used in the diagnosis of diseases.

Hydroxyurea

A medication prescribed to patients with sickle-cell anemia that stimulates the production of fetal hemoglobin.

Essential amino acids

Nine amino acids that must be obtained from the diet, as they cannot be synthesized by the body.

Peptide bond

The bond formed between the carboxyl group of one amino acid and the ammonium group of another.

R group

The side chain of an amino acid that determines its properties and classification.