Proteins Flashcards
What is another name for a peptide bond?
amide bond
What is a usefull function of the negative charge of proteins?
It can buffer a solution
What direction does a primary structure go?
From N terminus to C terminus
how is a secondary structure stabilized?
Via hydrogen bonds between the R groups
What is a beta turn?
a type of secondary structure that is composed of PROLINE
What does proline do in a tertiary structure?
It contributes to the bends and turns.
What helps a tertiary structure remain stable?
cysteine bonds (disulfur bonds are cysteine to cysteine sulfur bonds)
What are two key examples of quaternary proteins?
hemoglobin and antibodies
What type of bond is a peptide bond?
covalent
What does denaturing protein bonds do?
breaks all of the bonds except the covalent peptide and disulfur bonds.
What enzyme can break peptide bonds?
protease
What is the best method of determining the 3D structure of a protein?
Xray diffraction
What does electrophoresis do?
separates proteins based on size and charge
What are the 5 groups of amino acids?
- non-polar, aliphatic R groups
- Aromatic R groups
- Polar, uncharged R groups
- Positively charged R groups
- Negatively charged R groups
What is the only amino acid that is not Chiral?
glycine
Which amino acids are aromatics?
Its pheny when you tryp on a tyre
phenylalanine
tryptophan
tyrosine
What are the positively charged amino acids?
Basically (+) the HISTory of ARGINtina is a LYe
histadine
arginine
lysine
What are the negatively charged amino acids?
Ass and gluts are negative
aspartate
glutamate
Which amino acids are exclusively ketogenic?
leucine and lysine (L and L)
Which amino acids are both glucogenic and ketogenic?
PhITTT (they are so fit that they can do both!)
phenylalanine isoleucine tyrosine threonine tryptophan
What is an amino acid called if its broken down for energy?
alpha keto acids
Which configuration are amino acids in? L or D?
ALL of us want to be a DDS
Amino acids - L
Sugars - D
Which amino acids are made from pyruvate?
LIVA pye
Leucine, isoleucine, valine, alanine
What is the R group for alanine?
methyl group
What protein is found in collagen and elastin?
glycine (about 33% of them is glycine)
What is the amino acid that is the simplest structure with a hydrogen for its R group?
glycine
What is glycine used to make?
creatine, purines, porphyrin
Glycine CREATES PURE PORES
*its also used to make glycocholic acid ( a bile salt)
What amino acid substitution creates sickle cell anemia?
valine is substituted for glutamate
What is the amino acid in a start codon?
methionine (AUG)
What amino acid is only essential in people with phenylketonuria?
phenylalanine, which makes tyrosine
What are the two source of the urea cycle?
aspartate and carbamoyl phosphate
What are hydroxyproline and hydroxylysine?
Non-standard amino acids found in collagen.
What is lysyl hydroxylase?
an enzyme that adds the OH group to proline and lysine to make hydroxyproline and hydroxylysine.
What does lysyl hydroxylase require to work?
Vitamin C
What is the most abundant protein in blood serum?
albumin
What is the most abundant protein in the body by weight?
collagen
What form of collagen is in the cytosol of a fibroblast?
procollagen
How does elastin differ from collagen other than its stretchiness?
elastin has lysine crosslinks
collagen has disulfide crosslinks
What does transferrin do?
transports Iron
What is cytochrome?
a protein that has a metal core, usually of iron and acts to transport electrons like in the ETC
