Flashcards in Chapter 5 Definitions/Concepts Deck (36)
A molecule bound reversibly by a protein, can be any kind of molecule
Where the ligand binds the protein. Complementary to the ligands size, shape, charge and hydrophobic/hydrophilic characteristics.
Ligand binding to a binding site is usually highly specific
Multiple Binding Sites
Proteins can have more than one binding site to bind more than one kind of ligand
Conformational changes can be subtle or dramatic and are essential for protein function
A change in the proteins binding site that makes the binding of the ligand more desirable
The molecules acted upon by an enzyme in a reaction
Prosthetic group for binding oxygen, found in hemoglobin and myoglobin
When one O2 is bound it triggers the other subunits from T state to R state, therefore increasing the affinity for more O2 to bind.
Conformation that is more stable in the absence of oxygen
Conformation that has a higher binding affinity for oxygen
Binding of the ligand to one site affects the binding properties of another site on the same protein
Oxygen binding pressure
The partial pressure of oxygen in the lungs and tissues affect its ability to bind to hemoglobin
Measures the degree of cooperatively. When it equals 1 binding is not cooperative. When it is greater then 1 binding is cooperative.
Inverse Hemoglobin Binding Relationship
The binding of H and CO2 is inversely proportional to the binding of O2. When the pH is low and CO2 concentration is high the tissues decrease the affinity of hemoglobin for O2, therefore releasing it into the tissue.
H binding on hemoglobin
Doesn't bind to heme group. Binds to any of the amino acids which causes the structure to favor the T state.
CO2 binding to hemoglobin
Doesn't bind to heme group. Binds to N-terminal end of any of the 4 polypeptide chains
CO binding to hemoglobin
Does bind to heme group with higher affinity then oxygen, therefore reducing oxygen concentration in the body
Sickle Cell Anemia
Hereditary disease with abnormal shaped and fewer erythrocytes. Caused by amino acid substitution in the beta chains, creating hemoglobin s.
Has fewer negative charges, protein aggregates into long fibers
Molecule or pathogen capable of eliciting an immune response
The part of an antigen the antibody recognizes
Major class of antibody comprised of 4 polypeptide chains, 2 heavy and 2 light. Connected by disulfide bonds and non-covalent interactions to form a y-shaped molecule
Part of the immunoglobin G, has amino acids that recognize and bind antigens
Conferred by chemical complementarity between antigen and specific binding site
Model of Induced Fit Binding
Conformational changes occur to facilitate the most favorable interactions. Shape can change greatly when antigen is introduced
Kd is very small, they bind tightly
Many different antibodies recognizing different epitopes of the same antigen
A single antibody recognizing a single epitope of an antigen