Chpt 19

Amino Acids

Smaller molecules that link together in a chain to form proteins.

Proteins

Large biological molecules that carry out various functions in living organisms.

Hemoglobin

A protein that transports oxygen in the blood.

Sickle-cell anemia

A disease caused by an alteration in the amino acids of the hemoglobin protein, resulting in a crescent-shaped red blood cells and a deficiency in oxygen transport.

Hematology Nurse

A nurse who specializes in treating patients with blood disorders.

Oncology Certified Nurse (OCN)

A certification for nurses specializing in oncology (cancer) nursing.

Certified Pediatric Hematology Oncology Nurse (CPHON)

A certification for nurses specializing in pediatric hematology oncology.

Classification of Proteins

Categorization of proteins based on their functions.

Structural Proteins

Proteins that provide structural components in organisms, such as collagen in tendons and keratin in hair and nails.

Contractile Proteins

Proteins that enable muscle movement, such as myosin and actin.

Transport Proteins

Proteins that carry essential substances throughout the body, such as hemoglobin for oxygen transport and lipoproteins for lipid transport.

Storage Proteins

Proteins that store nutrients, such as casein in milk and ferritin for iron storage.

Hormone Proteins

Proteins that regulate body metabolism and growth, such as insulin and growth hormone.

Enzyme Proteins

Proteins that catalyze biochemical reactions in cells, such as sucrase and trypsin.

Protection Proteins

Proteins that recognize and destroy foreign substances, such as immunoglobulins.

Primary Structure of Proteins

The specific order of amino acids in a protein chain.

Three-dimensional Shape of Proteins

The folding of a protein chain, determined by the order of amino acids, which determines the protein's function.

Red Blood Cells (RBCs)

Blood cells that transport oxygen, affected in sickle-cell anemia.

Crescent Shape

The abnormal shape of red blood cells in sickle-cell anemia, caused by the abnormal hemoglobin protein.

Amino acids

Molecular building blocks that make up proteins.

Proteins

Complex molecules composed of amino acids.

Nonpolar amino acid

An amino acid with a hydrophobic R group.

Polar amino acid

An amino acid with a hydrophilic R group.

R group

The side chain of an amino acid that determines its unique characteristics.

Hydrophobic

"Water fearing" property of nonpolar amino acids.

Hydrophilic

"Water loving" property of polar amino acids.

Neutral amino acid

A polar amino acid with a hydroxyl, thiol, or amide group in its R group.

Acidic amino acid

A polar amino acid with a carboxylate group in its R group.

Basic amino acid

A polar amino acid with an amino group in its R group.

Polarity of amino acids

Classification of amino acids as nonpolar or polar based on their R groups.

Alkyl group

A nonpolar R group consisting of carbon and hydrogen atoms.

Amide group

A polar R group containing a nitrogen atom bonded to a carbonyl group.

Physiological pH

The pH value of 7.4, which is the pH of the human body.

Three-letter and one-letter abbreviations

Short forms used to represent the names of amino acids.

Amino acids

The building blocks of proteins.

Proteins

Complex molecules made up of amino acids.

Primary structure

The sequence of amino acids in a protein.

Three-letter abbreviation

A shortened form of the name of an amino acid.

One-letter abbreviation

A single letter used to represent an amino acid.

Physiological pH

The pH level at which an amino acid exists in its natural state.

Serine

An amino acid with the three-letter abbreviation "Ser" and the one-letter abbreviation "S".

Aspartate

An amino acid with the three-letter abbreviation "Asp" and the one-letter abbreviation "D".

Leucine

An amino acid with the three-letter abbreviation "Leu" and the one-letter abbreviation "L".

Cysteine

An amino acid with the three-letter abbreviation "Cys" and the one-letter abbreviation "C".

Tyrosine

An amino acid used to make melanins, thyroid hormones, and chemical messengers.

Cystinuria

A rare inherited disease characterized by a high concentration of cystine in the urine.

Hemoglobin

A protein that carries oxygen in the blood.

Collagen

A protein found in tendons and cartilage.

Keratin

A protein found in hair.

Amylases

Proteins that catalyze the hydrolysis of starch.

Insulin

A protein needed for glucose utilization.

Antibodies

Proteins that disable foreign proteins.

Casein

A milk protein.

Lipases

Proteins that catalyze the hydrolysis of lipids.

Functional groups

Specific groups of atoms that give amino acids their unique properties.

R group

The variable group in an amino acid that determines its specific properties.

Polarity

The distribution of electrical charge in a molecule.

Glycine

An amino acid with the three-letter abbreviation "Gly" and the one-letter abbreviation "G".

Glutamate

An amino acid with the three-letter abbreviation "Glu" and the one-letter abbreviation "E".

Phenylalanine

An amino acid with the three-letter abbreviation "Phe" and the one-letter abbreviation "F".

Lysine

An amino acid with the three-letter abbreviation "Lys" and the one-letter abbreviation "K".

Proline

An amino acid with the three-letter abbreviation "Pro" and the one-letter abbreviation "P".

Valine

An amino acid with the three-letter abbreviation "Val" and the one-letter abbreviation "V".

Tyrosine

An amino acid with the three-letter abbreviation "Tyr" and the one-letter abbreviation "Y".

Polar

Amino acids with a partial positive or negative charge.

Nonpolar

Amino acids without a partial positive or negative charge.

Hydrophobic

Amino acids that repel water.

Hydrophilic

Amino acids that attract water.

Alanine

An amino acid with the three-letter abbreviation "Ala" and the one-letter abbreviation "A".

Glutamine

An amino acid with the three-letter abbreviation "Gln" and the one-letter abbreviation "Q".

Cysteine

An amino acid with the three-letter abbreviation "Cys" and the one-letter abbreviation "C".

Tryptophan

An amino acid with the three-letter abbreviation "Trp" and the one-letter abbreviation "W".

Methionine

An amino acid with the three-letter abbreviation "Met" and the one-letter abbreviation "M".

Proline

An amino acid with the three-letter abbreviation "Pro" and the one-letter abbreviation "P".

Glycine

An amino acid with the three-letter abbreviation "Gly" and the one-letter abbreviation "G".

Peptide bond

An amide bond that links amino acids together to form a protein.

Dipeptide

A chain of two amino acids linked by a peptide bond.

Tripeptide

A chain of three amino acids linked by peptide bonds.

Tetrapeptide

A chain of four amino acids linked by peptide bonds.

Pentapeptide

A chain of five amino acids linked by peptide bonds.

Amino Acids

Building blocks of proteins.

Proteins

Polypeptides of 50 or more amino acids with biological activity.

Glycine

Amino acid with the abbreviation Giy. G.

Alanine

Amino acid with the abbreviation Ala. A.

Peptide bond

Bond formed between two amino acids.

Glycylalanine

Dipeptide formed by a peptide bond between glycine and alanine.

Water

H2O, produced during the amidation reaction for the formation of a dipeptide.

N-terminus

The end of a peptide with a free (unbonded) -NH/ group.

C-terminus

The end of a peptide with a free (unbonded) -coo- group.

Naming Peptides

Peptides are named from N-terminus to C-terminus, with the exception of the amino acid at the C-terminus.

Tripeptide

Peptide consisting of three amino acids.

Threonine

Amino acid with the abbreviation Thr. T.

Leucine

Amino acid with the abbreviation Leu. L.

Phenylalanine

Amino acid with the abbreviation Phe. F.

Primary Structure

The particular sequence of amino acids in a protein held together by peptide bonds from N- to C-terminus.

Hormone

A signaling molecule produced by glands in the endocrine system.

Glu-His-Pro

A tripeptide hormone that stimulates the thyroid to release thyroxin.

R groups

Side chains of amino acids that determine their unique properties.

Backbone

The repeating sequence of atoms in a peptide or protein, including the N in the ammonium group, the C from a carbon, and the C from the carboxylate group.

Biological Function

The specific sequence of amino acids in peptides and proteins determines their biological activity.