Myoglobin, Hemoglobin, and Ligand Binding

myoglobin is a _____________ (_____)

monomer (3 degree)

myoglobin requires a ___________ group in order to function

heme

myoglobin is found in?

skeletal muscle

hemoglobin is a _____________(______)

tetramer (4 degree)

hemoglobin is comprised of _______ _____________

4 subunits

each _____________ has a _______________ ___________

subnunit; heme group

hemoglobin is found?

in RBC and transports O2

cofactors are molecules that give you ___________ __________ that an amino acid cannot do own their own.

added functionality

inorganic cofactor =

vitamins

organic cofactor =

minerals

prosthetic groups are?

cofactors that bind covalently to proteins

an example of a prosthetic group is?

heme

apo:

protein WITHOUT a cofactor bond

holo:

protein WITH a cofactor bond

ligand

any small molecule that will bind a protein

coenzyme

vitamins that can participate in chemical reactions

Kd is known as the?

equilibrium dissociation constant

dissociation:

breaking apart of PRL into protein and ligand

Ka is known as the?

equilibrium association constant

association:

creation of protein and ligand into PRL

Ka should always be in __________

M-1

Kd should always be in _________

M

LOW Kd = ligand binds with ___________ affinity

HIGH

HIGH Ka = ligand binds with _____________ affinity

HIGH

when the change in G dissocation is more POSITIVE, the ligand has a _________ affinity

HIGH

when the change in G association is more NEGATIVE, the ligand has a _____________ affinity

HIGH

saturation: how much ___________ is bound to the protein in comparison to the _________ ____________

protein; total amount

how to calculate total amount of protein:

PR + PRL

saturation is defined as: ________

Y

how to calculate Y =

PRL/ PR + PRL

to calculate percent saturation you ____________ ___ by ______

multiply Y by 100

through substituion with Y and and Kd, you get Y =

[L]/ Kd + [L]

alpha h: hill coefficient: __________ _____________

cooperativity constant

cooperativity: defines what effect binding of __________ __________ has on the _____________ of ___________ ____________

effect binding of one ligand has on subsequent ligands

if the alpha h is greater than one, ______________ cooperativity: means that….

positive; binding of one ligand ENHANCES the binding of others

if the alpha h equals one, _______________ cooperativity: means that….

NO cooperativity! binding of one ligand HAS NO EFFECT on binding of others

if alpha h is less than one, ______________ cooperativity: means that…

negative, binding of one ligand REDUCES the binding of others

you will never see a _______________ alpha h!

negative

in a de-ozy hb state, ________ is ________ __________

O2 is not bound

in a de-oxy hb state, the heme group is ________________ and _____________ (____- state), which therefore it was _______ affinitiy.

stretched and tense (T-state), low affinity

in the transition state, _____ is bound to ______ in the _______ ________

O2 is bound to Fe 2+ in heme group

in the transition state, the heme group starts to undergo _______________ _______________ and starts to __________ out

structural rearrangements; flatten out

in the oxy-hb state, __________ is ____________

O2 is bound!

in the oxy-hb state, __________ group is ___________ (____-state)

heme group is relaxed (R-state)

in the oxy-hb state, there is _________ affinity for O2

high

what is allosteric control of proteins: the influence of binding a molecule to a site ___________ from where the ligand binds the protein

AWAY

homotropic modulators: _____________ and _____________ are ____________

modulator and ligand are the same

heterotropic modulators: ______________ and ____________ are ______________

modulator and ligand are different

modulators can increase the affinity of ligands to proteins through _______________ cooperativity

positive

the bohr effect describes the relationship btwn ______ and __________ binding

pH and O2

what is it called when the pH is above 7.4, which means it has a lower affinity, and it is in a Tstate?

acidosis

what is it called when the pH is less than 7.4, and has a high affinity for O2, and it is in a Rstate?

alkalosis

haldane effect describes how ___________ binds

carbon dioxide

when Hb is bounded to ____, it ___________ the affinity for O2, shifting to the _________

CO2, decreases, right

most of the CO2 in our body is bound to ___________________

bicarbonate

2,3 biphosphoglycerate (BPG) regulates ________ binding

Oxygen

Hb with ___________ has a __________ affinity for O2, and shifts to the ______________

BPG, lower, right

fetal Hb has a _________ affinity for O2, which means it is more to the ____________  compared to adults, and also favors the ____- ________!

higher; left; R-state

mutations lead to differences in?

oxygen binding

if something favors something, it means it ________

stabilizes

if something favors the other state, it means it _____________

destabilizes