Lecture 7: Proteins Flashcards
what is a zwitterion
is a neutral ion with charged portions
What does the pKA tell you about the amino acid
pKa= -log (Ka) characteristic of the strength of an acids
___________ The Ph at which the overall net charge of the molecule is 0
PI isoelectric point
What are the Non polar amino acids
A Giraffe Licks Icy Puddles, Vigorously”
-Alanine A
-Glycine G
-Leucine L
-Isolucine I
-Proline P
-Valine V
In myoglobin the polypeptide sequence ala-leu-val is most likely in which part of the molecule?
The inside because it is non polar
___________________:
‣ Defective breakdown of BCAA
‣ Distinctive sweet odor of urine
‣ Toxic build-up of BCAA and
respective metabolites
‣ Neurotoxicity if not treated
‣ Treatment - special diet
Maple syrup urine disease
What are the aromatic compounds
Phenylalanine (non polar)
Tyrosine (polar)
Tryophan (polar)
____________ is caused by a build up of phenylalanine in the body
Phenylketonuria
Tyrosine is a precursor for ___________
catecholamine
Tryptophan is a _________________
serotonin
What are the sulfur containing amino acids
Methionine and cystine
_______________ is a disorder of the proximal tubule reabsorption of the fuiltereced cystine and dibasic amino acids (ornithine, arginine, lysine)
Cystinuria
What does cystunuria
The inability to reabsorb cystine leads to accumulation and subsequent precipitation of stone of cystine in the urinary tract
What are the polar amino acids
*hydrophilic
Serine (S)
Threonine (T)
Asparagine (N)
Glutamine (Q)
What are the Charged amino acids
Negative:
Aspartate
glutamate
Positive
Arginine
Lysine
Histidine
What are the properties of charged amino acids
Basic or acidic
‣ Highly hydrophilic
‣ Participate in ionic interactions
‣ More complicated titration curve
What amino acids can be synthesized in a biochemical pathway in humans
Leucine and Lysine
What amino acids are not essential in normal conditions but can become so to meet demands
Tyrosine
Isoleucine
Phenyulalnine
Tryptophan
What amino acid is essential in trauma patients
glutamine and arginine
What amino acid is essential during childhood growth
Arginine
What are the 9 essential amino acids
“Pretty Vagina takes turns in Make Happy Lovers Laugh”
Phenylalanine
Valine
Threonine
Tryptophan
Isoleucine
Methionine
Histidine
Leucine
Lysine
What is primary structure
The unique sequence of amino acids arrange to form a polypeptide
__________ patients with a mutation in the hemoglobin polypeptide chain results in the substitute of glutamic acid for valine
sickle cell disease
What is secondary structure
Alpha helix or beta sheet
Maintained by hydrogen bonds formed between carboxyl oxygen and amine hydrogen in polypeptide backbone
In terms of B sheet what determines if it is Parallel or antiparallel
the folding of the sheet
If regular patterns are alpha helix and beta pleasted sheet, what are some non normal patterns
Bends loops turns
What is tertiary structure
The pattern of secondary structure elements folding into unique #D conformations. Maintained by the interaction of side chains
EX: disulfide bridges and ionic interactions
G actin and B adregeric receptors are example of ________ structure
tertiary structure
What is quaternary structure
the association of individual polypeptide chains subunits in a geometrically and stoichiometrically specific manner
Ex: hemoglobin, insulin, immunoglobulin
____________ is the destruction of a proteins quaternary, tertiary, or secondary structure
protein denaturation
✓ Nonenzymatic modifications:
‣glycosylation
‣oxydation
‣nitrosylation etc.
✓ High temperature:
‣fever above 40 C is a medical emergency
✓ Very low or very high pH:
‣stomach juice - pH 4.5
‣metabolic conditions - lactic acidosis, ketoacidois, alkalosis etc
