Mcb Test 1

Front 1

sequence of amino acid residues linked together by peptide bonds

Back 1

primary structure

Front 2

regular structures formed via hydrogen bonding of the carbonyl & amide groups of amino acid residues that are nearby in sequence

Back 2

secondary structure

Front 3

tertiary structurearrangement of secondary structure elements to form 3D structure of an intact polypeptide chain

Back 3

tertiary structure

Front 4

spatial arrangement of subunits & the nature of their reactions

Back 4

quarternary structure

Front 5

substructure produced by any part of a polypeptide chain that can fold independently into a compact, stable structure

Back 5

domain

Front 6

any region of a protein's surface that can interact with another molecule through sets of noncovalent bonds

Back 6

binding site

Front 7

an individual protein chain in a protein composed of more than one chain

Back 7

protein subunit

Front 8

2 identical folded polypeptide chains binded to each other "head-to-head" (symmetrical)
ex) Cro repressor protein

Back 8

dimer

Front 9

a protein that has 2 identical alpha-globin subunits and 2 identical B-globin subunits symmetrically arranged
(carries oxygen into red cells)

Back 9

hemoglobin

Front 10

a subset of protein domains that have been especially mobile during evolution, and can often be found in many diff proteins

Back 10

protein module

Front 11

type of chromatography in which the protein mixture to be purified is passed over a matrix to which specific ligands for the required protein are attached, so that the protein is retained on the matrix

Back 11

affinity chromatography

Front 12

why do proteins of the same size tend to move through gel with similar speeds?

Back 12

- their native structure is completely unfolded by SDS so the shapes are the same
- they bind to the same amount of SDS & have same amount of neg charge

Front 13

ratio of activity vs. actual amount of proteins

Back 13

specific activity

Front 14

if pH < pI, the protein carries a __ charge and moves to __ end in isolelectric focusing

Back 14

positive, -- end

Front 15

if pH > pI, the protein carries a __ charge and moves to __ end in isoelectric focusing

Back 15

negative, + end

Front 16

positively charged resin, binds negatively charged molecules

Back 16

anion exchanger

Front 17

negatively charged resin, binds positively charged molecules

Back 17

cation exchanger

Front 18

any substance bound to a protein

Back 18

ligand

Front 19

what does binding depend on?

Back 19

the formation of non-covalent interactions btwn protein & its ligand

Front 20

in MALDI-TOF, what determines how fast it takes them to reach the detector

Back 20

mass to charge ratio

Front 21

three ways proteins bind to other proteins

Back 21

surface-string, helix-helix, surface-surface

- surface-surface most common

Front 22

two major forces that influences all chemical rxns

Back 22

- tendency to achieve most stable bonding state
- tendency to achieve highest degree of randomness

Front 23

True or False- actual free-energy and the standard free-energy change determines whether or not a rxn can occur spontaneously

Back 23

FALSE- only the actual free energy change can do that

Front 24

an additional chemical component other than amino acid residues that is required for activity of some enzymes

Back 24

cofactor

Front 25

cofactor that is a complex organic molecule

Back 25

coenzyme

Front 26

coenzyme that is very tightly or even covalently bound to enzyme protein

Back 26

prosthetic group

Front 27

complete, catalytically active enzyme together w/ its bound coenzyme and/or metal ions

Back 27

holoenzyme

Front 28

protein part of holoenzyme

Back 28

apoenzyme

Front 29

3 kinds of molecular motions that help enzymes find substrates

Back 29

1. movement of a molecule from 1 place to another (translational)
2. rapid back-and-forth movements of covalently linked atoms w/ respect to one another (vibrations)
3. rotations

Front 30

process in which molecules are in constant translational motion causing them to explore the space inside the cell

Back 30

diffusion

Front 31

hypothesis that states that a substrate fits a perfectly matched active site on the enzyme

Back 31

lock & key

Front 32

hypothesis that states that once a substrate was in place, the enzyme changed conformation to bind it better & stabilize the "transition state"

Back 32

induced fit

Front 33

maximum rate divided by enzyme concentration

Back 33

turnover number

Front 34

hormone that stimulates uterin contraction

Back 34

oxytocin

Front 35

hormone which prevents urination at night

Back 35

vasopressin

Front 36

hormone which stimulates blood vessel contriction

Back 36

endothelin

Front 37

hormone which stimulates glucose uptake

Back 37

insulin