Ceutics Test 3 Sem 2 Lecture 2 Packet

Front 1

what produces the product in bacteria

Back 1

plasmid construct

Front 2

what does the plasmid construct do

Back 2

produces the product in the bacteria

-large bacterial fermenters are equipped to grow bacteria containing the construct of interest

Front 3

what must the construct have/do

Back 3

have sequences that signal its secretion into the growth medium

be active when produced by bacteria (bacteria don't glycosylate proteins)

Front 4

do bacteria glycosylate proteins

Back 4

no

Front 5

how are proteins manufactured

Back 5

bacteria w/ plasmid of interest placed in beaker

bacteria secretes protein

harvest protein

purify proteins via column chromatography

Front 6

what is the
1
2
3
4
structures made of

Back 6

1 - amino acids
2 - alpha helix/beta pleated sheets
3 - folded individual peptide
4 - two or more peptides

Front 7

how are the functional properties of proteins derived

Back 7

from their folding into distinct 3D structures

Front 8

what is protein folding based on

Back 8

its specific polypeptide sequence in which different amino acids are connected through peptide bonds in a specific way

Front 9

what are the noncovalent forces

Back 9

hydrogen bonding
van der waals
hydrophobicity
protein hydration

Front 10

what happens to proteins as temperature increases

Back 10

they unfold (this temp is called Tm)

Front 11

what is a hydrophobic interaction

Back 11

summation of van der waals attractive forces among non polar regions of the protein interior, which changes the surrounding water structure necessary to accommodate these groups if they become exposed

Front 12

what is a hydrogen bond

Back 12

ionic in character b/c it depends on the sharing of a protein between electronegative atoms (O2/N)

Front 13

where may hydrogen bonds form

Back 13

between protein and water molecules

exclusively as protein intermolecular hydrogen bonds

Front 14

what are electrostatic interactions

Back 14

occurs between two charged groups

same sign = repulsion and increase in energy

opposite sign = attraction and decrease in energy

Front 15

what are van der waals

Back 15

exists between atoms (not bare protons) whether they are polar or non polar

Front 16

how do van der waals arise

Back 16

they arise from the net attractive interactions between temporary dipoles and/or permanent dipoles

Front 17

what occurs in protein hydration

Back 17

the water array is disordered by protein

hydrogen bonds between water and protein surface stabalize

Front 18

what may cause physical instability of proteins

Back 18

changes in 3D structure due to unfolding, unnatural refolding, changes in hydrophobic interactions, changes in hydrogen bonding

Front 19

what are the different types of physical isntbilities that proteins may face

Back 19

surface adsorption
denaturation
aggregation
precipitation

Front 20

what is denaturation

Back 20

alteration of global fold of a native molecule (disruption of tertiary and frequently secondary structure)

Front 21

what is surface adsorption

Back 21

adhesions of proteins to surface (insulin)

Front 22

what is aggregation

Back 22

placement of proteins in aqueous solutions resulting in self association of proteins forming dimers, tetramers, hexamers, and macromolecular aggregates

Front 23

what is precipitation

Back 23

macroscopic equivalent of aggregation, occurs in conjunction w/ denaturation

Front 24

what is chemical instability of proteins

Back 24

molecular modification of proteins via making or breaking covalent bonds resulting in the formation of a new chemical entity

Front 25

what are examples of chemical instability

Back 25

hydrolysis (deamidation)
oxidation
racemization
disulfide exchange

Front 26

what is hydrolysis

Back 26

water molecules attack a bond causing cleavage of a peptide

Front 27

what is deamidation

Back 27

a type of hydrolysis

hydrolysis of a side chain of glutamine or asparagine residue

Front 28

what occurs as a result of deamidation

Back 28

results in a additional negative charge which can alter the tertiary structure

Front 29

what is oxidation

Back 29

occurs b/c interactions w/ molecular oxygen, hydrogen peroxides, free radicals

Front 30

what is susceptible to oxidation

Back 30

aromatic side chains
cysteine
methionine

Front 31

what can influence oxidation

Back 31

temp
pH
buffers
catalyst
O2 tension
amino acid neighbors

Front 32

what do amino acid neighbors do

Back 32

they influence oxidation of a protein

Front 33

what is racemization

Back 33

process of conversion of L amino acids to D,L mixtures and occurs through carbanion intermediate

Front 34

what does racemization do

Back 34

alters biological activity

Front 35

what is disulfide exchange

Back 35

exchange is catalyzed by thiols, occuring as a result of oxidation of disulfide groups

Front 36

what can be used to prevent disulfide exchange

Back 36

thiol scavengers

Front 37

what promotes intramolecular and tertiary structures

Back 37

disulfide exchange

Front 38

what are the noncovalent changes that occur to a protein

Back 38

aggregation
precipitation
surface adsorption
denaturation

Front 39

what are the covalent changes that occur to a protein

Back 39

oxidation
deamidation
racemization
hydrolysis
disulfide exchange

Front 40

what is deglycosylation

Back 40

a type of hydrolysis

Front 41

what are the mechanical forces

Back 41

shearing
shaking

Front 42

what occurs in shearing

Back 42

protein unfolding, refolding in a nonnative form

Front 43

what occurs in shaking

Back 43

causes foaming or an increase in the air-liquid interface and oxidation

Front 44

what are the analytical techniques

Back 44

SDS-PAGE
Immunoblotting
ELISA
Chromatography

Front 45

what occurs in protein denaturation

Back 45

native/functional protein
unfolding/refolding

partly or fully unfolded protein

noncovalent changes or covalent changes