Chapter Five And Six Flashcards
Amino acid sequence determines what
Protein shape
What type of boding maintains shape
Noncovalent bonding
What type of bonding determines flexibility and rotation
Covalent
What do you want the easiest shape to form
Least energy required to make
What are molecular chaperones
Help the protein fold correctly
What are some diseases that are caused by improper protein folding
Alzheimer’s, Huntington’s, creuzfeldt-Jakob
What are prions
Misfolding proteins in the brain
Symptoms of Parkinson’s
Resting tremor, rigidity, festinating Gate, dementia
Aggregates of misfolded proteins- prions- form what
Amyloid fibrils
What are some shapes of proteins
Globular, fibrous, sheets,rings, and spheres
What can help determine shape of protein in lab
X-ray crystallography, NMR, and threading
What are some folding patterns of proteins
Alpha helix, beta sheet and H bonding
Examples of alpha helix
Keratin
Where can keratin be found
Nails, hair, skin, horns
Example of beta sheet
Fibroid
Where can fibroin be found
Silk
Hydrogen bonds in alpha helixes bond with every what number of peptide bond
Fourth
What is a coiled coil
Two alpha helixes that tuck in the hydrophobic areas
In beta sheets, how do H bonds form
Between peptides that are laying side by side
Anti parallel has what size loop
Short loop
Parallel beta sheet has what type of loop
Long
What is an example of beta sheet
Antifreeze protein
What is a protein domain
Independently folding polypeptide chain from which other proteins are constructed
What are targets for proteins
Unstructured protein regions
What are unstructured protein regions
Larger proteins with numerous domains connect by polypeptide chain containing unstructured sequences
Are unstructured protein regions tucked into the protein
No, not folded
What are flexible tethers
Provide movement and flexibility, help scaffold proteins bring proteins together, intracellular signaling pathways, assist elastin in forming rubberlike fibers
Unstructured regions in UPRs can do what
Bend, flex, wrap around larger target proteins
What are protein families
Groups of proteins with similar amino acid sequences and conformations, look similar and have similar functions
What are examples of protein families
Serine proteases, chemotrypsin, trypsin, elastase
Dimer and tetrameres are examples of
Large protein molecules containing weak noncovalent forces
Example of large protein molecule
Hemoglobin
Filaments, sheets or spheres are larger proteins that depend on
Complimentary binding sites and have indefinite number of bindings
Elongated fibrous proteins spans
Long distances
Examples of elongated fibrous proteins
Keratin, extracellular matrix, collagen and elastin
What are extracellular proteins
Covalent cross linkages that strengthen proteins by formation of disulfide bonds that are found extracellularly
How do protein binding work
Proteins interact with ligands through weak or strong binding
Proteins have what type of binding with noncovalent bonds
Complementary binding
Function of antibodies
Hunt pathogens
Describe binding of antibodies
Tight and specific
Structure of antibody
Y shaped
Where is the specificity of binding in antibodies
At the y ends
How does binding occur in antibodies
Triggered by an immune response
Enzymes as catalysts are highly…
Specific for a single reaction
Function of lysozyme
Break down polysaccharide chains
How do lysozymes break down polysaccharides
Add water to molecule
Examples of non protein molecular coenzyme assistants
Retinal, heme molecules, and coenzymes
Catalytic activities of enzymes are regulated by
Gene expression, compartmentalizations, feedback regulation
What are the different types of binding in catalytic enzymes
Allosteric binding, phosphate binding
What are allosteric enzymes
Enzymes with two binding sites
How do allosteric enzymes work
Bind in both binding sites then change conformations
Function of phosphorylation
Involves attachment of a phosphate group to an amino acid side chain
Phosphorylation changes what in protein
Activity
Kinases function
Add phosphate
Phosphotases function
Take away phosphate
How do GTP binding proteins work
GTP in protein becomes hydrolyzed to form GDP inactivating the protein then GDP leaves protein, GTP then reactivates protein
Function of motor proteins
Cellular movement
What are protein machines
Large complexes that allow proteins to act in a coordinated manner due to hydrolysis of GTP or ATP
Example of covalent modifications in protein machines
Receptor tyrosine kinase
How are proteins studied in vitro
Cultured cells, differentiated properties are maintained, raw materials