Lecture 2 Flashcards
nuclear proteins
RNA, DNA
immunoglobulin example
antibody
invader that causes the immune response
antigen
proteins are made of
amino acids
L amino acid and D amino acid are blank
mirror images (stereoisomers)
molecule with both + and - charges
zwitterions
molecule that acts as acid base
ampholyte
charged ends of amino acids form blank bond
peptide
peptide bond aka blank bond
amide
two amino acids are joined with the accompanying loss of a water molecule
condensation reaction
condensation reaction is catalyzed by the blank
ribosome
water inhibits blank
protein synthesis
end terminus of peptide chain
carboxyl
terminus of peptide chain that is at the beginning
amino group
number of R group options…. R groups are amino acids in proteins
20
two cysteines can react together to form a strong covalent blank bond
disulphide
proteins are purified to be used in
drugs
gel electrophoresis distributes and purifies proteins according to blank
charge
small proteins migrate blank in gel electrophoresis
fast
ion exchange does not usually fully blank proteins
purify
size exclusions has blank getting through first
large
sds gel electrophoresis separates by size and allows large proteins through blank than smaller
slower
proton donor
acid
proton acceptor
base
strong acids and bases blank in water
dissociate completely
weak acids make good blank because they dissociate blank in water
buffers, incompletely
the larger Ka, the blank the tendency for the acid to dissociate
greater
large Ka means blank acid
strong
strong acid means a blank pKa
small
pKa = -(log10) Ka
henderson hasselbeck
Ka of a weak base is actually a measure of the dissociation a proton from its blank
conjugate acid
measure of ionizable species in a solution
titration curve
pH at which the net charge on species is zero on average
isoelectric point
at blank, 50% protonated 50% unprotonated
pKa
solution pH higher than the pKa of amino acid, then amino acid is blank
deprotonated
solution pH lower than the pKa of amino acid, then amino acid is blank
protonated (has all its protons)
net charge of protein is the blank of all ionic species
mean
henderson hasselbeck equation
pH = pKa + log (products/reactants)
a buffer is a weak acid or base and a blank of that weak acid or base
salt
biological buffers funciton
maintain homeostasis
2 carriers of oxygen proteins
hemoglobin, myoglobin
straight or branched CHn chain
aliphatic
nonpolar small aliphatic aa
gly, ala
Nonpolar, aliphatic (bulky)
VAL, LEU, ILE
Branched-chain
VAL, ILE, LEU, ARG, ASN, GLN
Aromatic
PHE, TYR, TRP
Charged, acidic (negative)
ASP, GLU
Charged, basic (positive)
HIS, LYS, ARG
Polar, uncharged, amides
ASN [–> ASP], GLN [–> GLU]
Polar, uncharged, hydroxy
TRY, SER, THR
Polar, uncharged, sulfur-containing
MET, CYS
only amino acid that is not optically active
glycine
very hydrophobic aromatics
phenylalanine, Tryptophan… not tyrosine because of hydroxyl group
blank side chains act as buffers at physiological pH
histidine
