Proteins Flashcards
What is the proteome
entire set of proteins expressed as one gene
-genes lower due to splicing
-affected by stress and disease
Where do cytosolic proteins begin sythesis
start and end in cytosolic ribosomes
where do transmembrane proteins begin synthesis
start in cytosolic ribosomes
signal sequence halts translation and docks ribosome to ER (RER)
Describe the movement of proteins
transported by vesicles in ER lumen and bud off to move to the golgi apparatus
Leave to go to plasma membrane or ribosomes
What is the significance of the golgi apparatus
location of post translational modification
-adds carbs
-proteolytic cleavage (makes inactive proteins active)
-phosphorylation
How are proteins secreted and give examples
secretory vesicles fuse w plasma membrane and are realeased
peptide hormones, digestive enzymes
Name types of R groups and their branch
Basic, NH3
Acidic, COO-, COOH
Polar, C=O, NH, OH
Hydrophobic, hydrocarbon
What is a primary protein structure
amino acids
What is the secondary protein structure and state their bonds
B pleated sheets, alpha helices and turns
H bonds
Describe Tertiary protein structure
polypeptide folds
stabilized by hydrophobic interactions, H bonds, ionic bonds, disulfide bridges and LDF
What is a quartenary protein structure
2 or more polypeptides joined together
-prosthetic groups (haem in haemoglobin)
-temp. and pH disrupt interactions
—pH disrupts R groups
What are ligands
substances that bind to proteins at a complimentary binding site (NOT ACTIVE SITE)
What is cooperativity
binding at one site increases affinity for other sites
What happens to cooperativity when PH DECREASES and TEMPERATURE INCREASES
AFFINITY DECREASES, O BINDING DECREASES, O2 IN RESPIRING TISSUE INCREASES
