Globular Proteins

This set of flashcards covers essential vocabulary and concepts regarding globular proteins, their structure, function, and biological significance, as discussed in the lecture notes.

Globular proteins

Spherical proteins that are soluble in water and perform specific biological functions.

Hemoglobin

A globular protein that transports oxygen in the blood.

Oxygen saturation curve

Graphical representation of the relationship between oxygen pressure and hemoglobin's oxygen binding.

Allosteric effectors

Molecules that bind to a protein and modify its activity; important in hemoglobin function.

Myoglobin

A globular protein that stores oxygen in muscle tissues.

Denaturation

Loss of structural integrity of proteins, resulting in loss of function.

Albumin

The most abundant protein in blood plasma, responsible for transporting various substances.

Globulins

A family of proteins in blood that include antibodies and transport proteins.

Hemeproteins

Proteins that contain a heme group, involved in oxygen transport.

Oxygen transport

The process of delivering oxygen to tissues through the blood.

Proximal histidine

A histidine residue that binds to iron in heme, facilitating oxygen binding.

Distal histidine

A histidine that stabilizes bound oxygen in hemoglobin.

Bohr effect

The physiological phenomenon where increasing carbon dioxide and decreasing pH reduce hemoglobin's affinity for oxygen.

2,3-BPG

A metabolite that binds to hemoglobin, reducing its affinity for oxygen and promoting oxygen release.

Hemoglobin A

The major form of hemoglobin found in adults, composed of four polypeptide chains.

Deoxyhemoglobin

Hemoglobin without oxygen, referred to as the 'tense' form.

Oxyhemoglobin

Hemoglobin bound to oxygen, referred to as the 'relaxed' form.

Carbon monoxide (CO)

A gas that competitively binds to hemoglobin, preventing oxygen transport.

Glycated hemoglobin (HbA1c)

A stable form of hemoglobin that indicates long-term glucose levels in individuals.

Sickle cell anemia

A genetic disorder where abnormal hemoglobin (HbS) causes distorted red blood cells.

Thalassemia

A blood disorder involving insufficient production of normal hemoglobin.

Quaternary structure

The arrangement of multiple polypeptide chains in a protein.

Hyperbolic oxygen dissociation curve

The graph for myoglobin illustrating a non-cooperative binding of oxygen.

Sigmoidal oxygen dissociation curve

The graph for hemoglobin displaying cooperative binding of oxygen.

Protein denaturation causes

Changes in environmental conditions such as temperature or pH.

Complex conformations

Three-dimensional shapes of proteins that determine their function.

Iron (Fe²⁺) in heme

The metal ion central to the heme group crucial for oxygen binding.

Saline solution

A solution of salt in water often used in biological research.

Polypeptide chain

A sequence of amino acids linked by peptide bonds forming a protein.

Metabolic control

The regulation of biochemical reactions within the body.

Flexible structure

Characteristics of proteins that allow movement and function.

pH effect on hemoglobin

Acidic conditions promote oxygen release due to protonation of histidines.

Hypoxia

A condition of inadequate oxygen supply to tissues.

Glycolysis

A metabolic pathway that converts glucose into pyruvate with the production of ATP.

Cyclic nature of heme synthesis

The production of heme occurring in the cytosol and mitochondria.

Erythrocytes

Red blood cells that carry oxygen through the bloodstream.

Hemoglobinopathies

Disorders caused by abnormalities in the structure or production of hemoglobin.

Immunoglobulins

Antibodies produced by the immune system to combat pathogens.

Xenobiotics

Foreign substances introduced into the body, such as drugs.

Heme group

An iron-containing structure within hemoglobin important for oxygen binding.

Negative modulators

Substances that decrease the activity of proteins like hemoglobin.

Hematopoiesis

The process of blood cell formation, including red blood cells.

Protein folding

The process by which a protein achieves its functional shape.

Lipid transport

The movement of fats and oils through the bloodstream, facilitated by proteins.

Enzymes

Proteins that catalyze biochemical reactions.

Subunits

Individual polypeptide chains that make up a protein.

Tissue oxygenation

The delivery of oxygen to body tissues for metabolic processes.

Cellular respiration

The process of producing energy (ATP) from nutrients.

Metabolite

A substance produced during metabolism.

Affinity for oxygen

The tendency of hemoglobin to bind oxygen.

Competitive inhibitor

A substance that binds to the active site of an enzyme, blocking substrate access.

Iron-binding proteins

Proteins that transport or store iron in the body.

Binding affinity

The strength of the interaction between a protein and a ligand.

Enzymatic reaction

A chemical process facilitated by an enzyme to accelerate metabolic reactions.

Ion exchange

The process of exchanging ions in a solution, often influencing protein function.

Hydrogen bonding in proteins

Non-covalent interactions that stabilize protein structures.

Polarity in amino acids

The distribution of electrical charge across a molecule, influencing protein behavior.

Disease marker

Biomolecules indicating the presence of a disease, such as HbA1c for diabetes.

Adaptive response to exercise

Physiological adjustments in muscles and blood to increase oxygen delivery during physical activity.

Environmental stressors

Factors such as temperature and pH that can disrupt protein structure.

Protein sequence determination

The order of amino acids in a protein, dictating its specific function.

Lipid solubility

The ability of a substance to dissolve in lipids; important for membrane interactions.

Polypeptide composition

The variety of amino acids forming a particular protein.

Dynamic equilibrium

A state where the rate of formation and breakdown of a substance is equal.

Physiological adaptation

Adjustments made by the body to maintain homeostasis under varying conditions.

Carboxyhemoglobin

Hemoglobin bound to carbon monoxide, hindering normal oxygen transport.

Homeostasis

The maintenance of stable internal conditions in an organism.

Molecular signaling

Communication processes involving molecules that affect cellular activities.

Nutrient transport proteins

Proteins that facilitate the movement of nutrients across cell membranes.

Pathophysiology of disease

The study of how disease processes affect bodily functions.

Molecular basis of oxygen transport

Mechanisms by which oxygen is carried in the bloodstream, primarily by hemoglobin.

Blood oxygen levels

The concentration of oxygen present in the blood.

Iron homeostasis

Regulation of iron levels in the body to prevent deficiency or overload.

Protein-protein interactions

Interactions between proteins that can affect their function and activity.