| Aerobic |
Refers to the presence of oxygen. |
|
Aerobic Glycolysis |
Refers to glycolysis which is occuring under
conditions where the electron transport system and oxidative
phosphorylation are occurring. This means oxygen must be present. |
|
Anabolic |
Refers to metabolic processes which build larger
molecules from smaller ones. |
|
Anaerobic |
Refers to the absence of oxygen or the absence
of a need for it. |
|
Anaerobic Glycolysis |
Refers to glycolysis which is occurring under
conditions in the absence of oxygen. When this process is occurring,
NADH must be recycled to NAD+. This usually occurs
by production of lactate from pyruvate (animals and some bacteria)
or by production of ethanol from pyruvate (yeast). |
|
Catabolic |
Refers to metabolic processes which break down
large molecules into smaller ones, releasing energy. Glycolysis
is one such pathway. |
|
Covalent Modification |
A means of regulating the activity of some enzymes.
In the case of glycogen phosphorylase or pyruvate kinase, it
involves putting on or taking off a phosphate group. When glycogen
phosphorylase has phosphates on it, it is in the active form.
On the other hand, when pyruvate kinase is phosphorylated, it
is less active. |
Figure 13.18
| Feedforward Activation |
Refers to metabolites in a pathway which allosterically
activate enzymes that are "ahead" of them in the pathway
in which they are metabolized. For example, fructose-1,6-bisphosphate
allosterically activates pyruvate kinase by such a mechanism. |
|
Fermentation |
An energy-yielding metabolic pathway that
involves no net change in oxidation state. Anaerobic glycolysis
is one example. |
|
Glycosidic bonds |
Sugars, such as glucose that form ring structures
create an asymmetric carbon called an anomer at the site of closing
of the ring. This is carbon #1 for aldohexoses and carbon #2
for ketohexoses. If the hydroxyl group on the anomeric carbon
is joined to another molecule, such as a sugar, so as to split
out water, the resulting bond is called a this kind of a bond.
Glycogen has many such bonds |
|
Isozymes |
Molecules that are different forms of the same
enzyme. |
|
Kinase Cascade |
Refers to the regulatory cascade involved in
hormonal control of cellular actions mediated through cAMP. |
Figure 13.18
| Lactose Intolerance |
Refers to a condition in humans that results
from disappearance of the enzyme lactase from the intestinal
mucosal cells after age 4 to 6. In these people, ingestion of
milk products causes intestinal distress, because of bacterial
action on the lactose that accumulates. |
|
Limit Dextrin |
Refers to the end product of digestion of amylopectin
or glycogen by  -amylase. -amylase
is unable to cleave maltose units off at 1->6 branch
point in the polysaccharides. |
|
Oxidative Phosphorylation |
Refers to one of the three ways in which ATP
is made from ADP in cells. This process occurs in the mitochondria
and requires both electron transport and oxygen. |
|
Pasteur Effect |
Refers to an observation that when anaerobic
yeast cultures that are metabolizing glucose are exposed to air,
the rate of glucose utilization decreases dramatically. This
is due to the fact that in air, aerobic glycolysis is favored
and it is much more efficient at producing ATP than anaerobic
glycolysis. |
|
Phosphorylation |
Refers simply to the addition of a phosphate
to a molecule. Enzymes that add phosphates to molecules are called
kinases. |
|
Photophosphorylation |
One of three cellular mechanisms for making ATP
from ADP. This process occurs in plants and photosynthetic bacteria.
Conversion of ADP to ATP by this process depends directly on
energy from sunlight. The light energy is captured by a pigment
such as chlorophyll and is passed in the form of excited electrons
to an electron transport chain; the electron transport chain
uses energy from the electrons to create a proton gradient across
a membrane, which drives the synthesis of ATP. |
|
Regulation |
With respect to enzymatic action, this term refers
to anything that affects the activity of the enzyme. It can also
refer to the control of an entire metabolic pathway. |
|
Respiration |
With respect to energy metabolism, the process
in which cellular energy is generated through the oxidation of
nutrient molecules with O2
as the ultimate electron acceptor. |
|
Substrate level phosphorylation |
One of three cellular mechanisms for making ATP
from ADP. Involves a high energy phosphorylated intermediate
which tranfers a phosphate to ADP to form ATP. The reaction catalyzed
by pyruvate kinase is an example. |
Table 13.1
Category - Enzymes
Query - What enzyme/reagent
has this activity?
Reversal
Category - Reactions
Query - What reaction does
the enzyme below catalyze?
(Enzyme on left, reaction in middle, figure
on right)
| Lactate dehydrogenase |
Pyruvate + NADH + H+ <=> Lactate + NAD+ |
|
Alcohol dehydrogenase |
Acetaldehyde + NADH + H+
<=> Ethanol + NAD+ |
|
Hexokinase |
-D-Glucose + ATP <=> -D-Glucose-6-Phosphate
+ ADP + H+ |
|
Phosphoglucoisomerase |
-D-glucose-6-phosphate <=> D-fructose-6-phosphate |
|
Phosphofructokinase |
D-fructose-6-phosphate + ATP <=> D-fructose-1,6-bisphosphate |
|
Aldolase (fructose-1,6-bisphosphate
aldolase |
D-fructose-1,6-bisphosphate <=> Dihydroxyacetone
phosphate + D-Glyceraldehyde-3-Phosphate |
|
Triose phosphate isomerase |
Dihydroxyacetone phosphate <=> D-Glyceraldehyde-3-Phosphate |
|
Glyceraldehyde-3-phosphate dehydrogenase |
D-Glyceraldehyde-3-Phosphate + NAD+
+ Pi <=> 1,3 bisphosphoglycerate + NADH + H+ |
|
Phosphoglycerate kinase |
1,3 bisphosphoglycerate + ADP <=> 3-phosphoglycerate
+ ATP |
|
Phosphoglycerate mutase |
3-phosphoglycerate <=> 2-phosphoglycerate |
|
Enolase |
2-phosphoglycerate <=> Phosphoenolpyruvate
+ H2O |
|
Pyruvate Kinase |
Phosphoenolpyruvate + ADP + H+
<=> Pyruvate + ATP |
|
Pyruvate decarboxylase |
Pyruvate + H+
+<=> Acetaldehyde + CO2
| |
Galactokinase |
Galactose + ATP <=> Galactose-1-Phosphate
+ ADP |
|
UDP-Glucose--D-Galactose-1-phosphate
uridylyltransferase |
Gal1P +UDP-Glucose <=> G1P
+ UDP-Galactose |
|
UDP-galactose epimerase |
UDG-Galactose <=> UDP-Glucose |
|
Phosphoglucomutase |
G1P <=> G6P |
|
Aldolase B |
F1P <=> dihydroxyacetone phosphate (DHAP)
+ D-glyceraldehyde |
|
Maltase |
Maltose + H2O <=>
2 Glucose |
|
Lactase |
Lactose + H2O <=>
D-Galactose + D-Glucose |
|
Sucrase |
Sucrose + H2O <=>
D-Fructose + D-Glucose |
|
Glycerol kinase |
Glycerol + ATP <=> Glycerol-3-Phosphate
+ ADP + H+ |
|
Glycerol-3-phosphate dehydrogenase |
Gly3P + NAD+
<=> DHAP + NADH + H+ |
|
amylase |
Cleavage of maltose units from glycogen (more
than 4 glucoses away from a 1,6 branch point) |
|
Debranching enzyme |
Debranching of glycogen chains |
Figure 13.17 |
Glycogen phosphorylase |
Cleavage of 1,4-linked glucoses
of glycogen to within 4 units of a 1,6 branch point to yield
glucose-1-phosphate and glycogen shortened by one
glucose unit. |
|
Phosphorylase b kinase |
Conversion of glycogen phosphorylase b to glycogen
phosphorylase a. |
Figure 13.18 |
Active protein kinase (cAMP-dependent
protein kinase) |
Conversion of inactive phosphorylase b kinase
to active phosphorylase b kinase . |
Figure 13.18 |
Adenylate cyclase |
ATP <=> AMP + PPi |
|
Category - Structures
Query - What is the structure
of the molecule below?
Reversal
Category - Molecules
Query - What is the name
of the molecule with the structure below?
(molecules on left, structures in middle,
figures on right)
| Pyruvate |
|
|
L-Lactate |
|
|
Ethanol |
|
|
Glucose |
|
|
-D-glucose-6-phosphate |
|
|
D-Fructose-6-phosphate |
|
|
D-Fructose-1,6-bisphosphate |
|
|
Dihydroxyacetone phosphate |
|
|
D-Glyceraldehyde-3-phosphate |
|
|
1,3-Bisphosphoglycerate |
|
|
3-Phosphoglycerate |
|
|
2-Phosphoglycerate |
|
|
Phosphoenolpyruvate (PEP) |
|
|
Acetaldehyde |
|
|
Fructose-2,6-bisphosphate |
|
|
Galactose |
|
|
Mannose |
|
|
Fructose-2,6-bisphosphate |
|
|
Lactose |
|
|
Maltose |
|
|
Sucrose |
|
|
Glucose-1-phosphate |
|
|
Glycerol |
|
|
Glycerol-3-phosphate |
|
|
cAMP |
|
|
AMP |
|
|
ADP |
|
|
ATP |
|
|
Category - General
Query - What is the function
or action of the molecule below?
Reversal -
Category - General
Query - What molecule has
the property described below?
(Molecule on left, function in middle, figure
on right)
| Calmodulin |
Interacts with phosphorylase b kinase to activate
it in the presence of calcium |
|
NADH |
Carry electrons released in oxidation to electron
transport chain |
|
NAD+ |
Accept electrons released in oxidation, forming
NADH |
|
PEP |
High energy glycolysis intermediate involved
in substrate level phosphorylation of ADP to form ATP |
|
1,3-bisphosphoglycerate |
High energy glycolysis intermediate involved
in substrate level phosphorylation of ADP to form ATP |
|
Fructose-2,6-bisphosphate |
Allosterically activate phosphofructokinase of
glycolysis and inhibit fructose-1,6-bisphosphatase of
gluconeogenesis |
|
Lactate |
Produced in lactate fermentation as a mechanism
of regenerating NAD+ for glycolysis. |
|
Ethanol |
Produced in ethanol fermentation as a mechanism
of regenerating NAD+ for glycolysis. |
|
Iodoacetate |
Chemically modifies thiol group in phosphofructokinase
and inhibits it |
|
Category - General
Query - What molecule(s)
is (are) the inhibitor(s) of the enzyme below?
Reversal - there is no reversal
(enzyme on left, inhibitors in middle, figures
on right)
| Phosphofructokinase |
ATP, Citrate |
|
Hexokinase |
Glucose-6-phosphate |
|
Pyruvate Kinase |
ATP, alanine, acetyl-CoA |
|
Category - General
Query - What molecule(s)
is (are) the inhibitor(s) of the enzyme below?
Reversal - there is no reversal
(enzyme on left, inhibitors in middle, figures
on right)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Enzyme |
Action |
Effect |
|
|
|
Pyruvate kinase |
phosphorylation |
inhibit |
|
|
|
Pyruvate kinase |
dephosphorylation |
activate |
|
|
|
Glycogen phosphorylase b |
phosphorylate |
activate (by converting it to phosphorylase a) |
|
|
|
Glycogen phosphorylase a |
dephosphorylate |
inactivate it (converts it to phosphorylase b) |
|
|
|
Phosphorylase b kinase (phosphorylated) |
dephosphorylate |
inhibit |
|
|
|
Phosphorylase b kinase (dephosphorylated) |
phosphorylate |
activate |
|
|
|
Category - General
Query - What molecule(s)
is (are) the activator(s) of the enzyme below?
Reversal - there is no reversal
(enzyme on left, activators in middle, figures
on right)
| Phosphofructokinase |
Fructose-2,6-bisphosphate, AMP |
|
Pyruvate Kinase |
Fructose-1,6-bisphosphate |
|
Glycogen phosphorylase b |
AMP |
|
cAMP-dependent protein kinase (protein
kinase) |
cAMP |
|
Category - General
Query - What what effect
does phosphorylation/dephosphorylation
have on the enzyme below?
(note to programmers - the program should pick an enzyme and either
phosphorylation or dephosphorylation)
Reversal - there is no reversal
(enzyme on left, action in column 2, effect
in column 3, there are no relevant figures)
| Enzyme |
Action |
Effect |
Pyruvate kinase |
phosphorylation |
inhibit |
Pyruvate kinase |
dephosphorylation |
activate |
Glycogen phosphorylase b |
phosphorylate |
activate (by converting it to phosphorylase a) |
Glycogen phosphorylase a |
dephosphorylate |
inactivate it (converts it to phosphorylase b) |
Phosphorylase b kinase (phosphorylated) |
dephosphorylate |
inhibit |
Phosphorylase b kinase (dephosphorylated) |
phosphorylate |
activate |
|