11. Amino Acids & Peptides/Proteins Flashcards
what 2 groups does amino acids contain
amine and COOH groups
what is the alpha carbon
stereogenic center so 2 enantiomers possible
what is the nomenclature for amino acids
L and D
in acids what is the charge of the amino acid
why
+1
from +NH3
in bases what is the charge of the amino acid
why
-1
due to COO-
in neutral solutions what is the charge of the amino acid
why
zwitterion
neutral charge
+NH3 and COO- both present cancel each other out
where do dipeptides form between in amino acids
2 amino acids
between the NH2 of one and COOH of the other amino acid
what is the N terminal amino acid
free NH2 to the left
what is the C terminal amino acid
free COOH to the right
what are peptides in terms of number of amino acids
<50 aa
what are proteins in terms of number of amino acids
> 50 aa
what relation is the amide bond with NH and C=O in a peptide/protein spatially
amide bond is planar with NH and 180 degrees to C=O
what are primary proteins
aa sequence in peptide chain
what are secondary proteins
H bonding producing coils
what are tertiary proteins
disulfide bond alter entire protein shape
