BIOMG 3300 Unit 3 Objectives Questions with
Correct Answers
Fe3+ Correct Answer-doesn't allow for reversible binding to O2
Fe2+ when bound to 2 heme groups Correct Answer-can cause the
formation of radicals, which are bad for the body
Ligand Correct Answer-a molecule reversibly bound by a protein
binding site Correct Answer-the place where a ligand binds to a protein
complementary in size/charge/shape/hydrophilic/hydrophobic character
induced fit Correct Answer-structural adaptation that occurs between
ligand and protein
substrate Correct Answer-a molecule acted on by an enzyme
catalytic/active site Correct Answer-ligand binding site on an enzyme
myoglobin Correct Answer-a protein used for oxygen storage in muscle
-very high affinity for O2, not sensitive to changes in [O2]
-hyperbolic affinity curve
-1 subunit, no cooperativity
, heme group Correct Answer-a prosthetic group bound to a protein that
incorporates and sequesters free Fe
Pyrrole ring Correct Answer-the actual unit of porphyrin ring (in heme
groups)
Order of AAs most likely to be in protein interior Correct Answer-1)
hydrophobic AAs
2) charged AAs
3) polar uncharged AAs
Fe has how many coordination points Correct Answer-6: 4 bound to
porphyrin ring, 1 bound to proximal His, 1 is O2 binding site
Globin Correct Answer-a family of proteins with similar 2' and 3'
structures, used for oxygen storage. Most have 8 alpha helices and have
heme nestled between 2 of them with 2 His residues coordinated to it
P50 Correct Answer-the PO2 where half of the molecule is bound to O2
(50% protein saturation)
proximal His role Correct Answer-Keeps Fe in heme group as Fe2+ by
binding to coordination bond
distal His role Correct Answer--increases heme's affinity for O2 by
forming an H bond with it/stabilizing it
Correct Answers
Fe3+ Correct Answer-doesn't allow for reversible binding to O2
Fe2+ when bound to 2 heme groups Correct Answer-can cause the
formation of radicals, which are bad for the body
Ligand Correct Answer-a molecule reversibly bound by a protein
binding site Correct Answer-the place where a ligand binds to a protein
complementary in size/charge/shape/hydrophilic/hydrophobic character
induced fit Correct Answer-structural adaptation that occurs between
ligand and protein
substrate Correct Answer-a molecule acted on by an enzyme
catalytic/active site Correct Answer-ligand binding site on an enzyme
myoglobin Correct Answer-a protein used for oxygen storage in muscle
-very high affinity for O2, not sensitive to changes in [O2]
-hyperbolic affinity curve
-1 subunit, no cooperativity
, heme group Correct Answer-a prosthetic group bound to a protein that
incorporates and sequesters free Fe
Pyrrole ring Correct Answer-the actual unit of porphyrin ring (in heme
groups)
Order of AAs most likely to be in protein interior Correct Answer-1)
hydrophobic AAs
2) charged AAs
3) polar uncharged AAs
Fe has how many coordination points Correct Answer-6: 4 bound to
porphyrin ring, 1 bound to proximal His, 1 is O2 binding site
Globin Correct Answer-a family of proteins with similar 2' and 3'
structures, used for oxygen storage. Most have 8 alpha helices and have
heme nestled between 2 of them with 2 His residues coordinated to it
P50 Correct Answer-the PO2 where half of the molecule is bound to O2
(50% protein saturation)
proximal His role Correct Answer-Keeps Fe in heme group as Fe2+ by
binding to coordination bond
distal His role Correct Answer--increases heme's affinity for O2 by
forming an H bond with it/stabilizing it
