[S] when enzyme is half its maximal velocity (half of enzyme working, half not)
Why is Hb not an enzyme?
enzymes involve making/breaking covalent bonds, Hb does not
process in which organisms take chemical energy present in fuel sources & convert in to synthesize complex, highly ordered macromolecules capable of doing biochemical work
energy transduction
(ex: gas in car converted into mechanical energy)
catabolism
oxidation of carbs, proteins, fat, which produce CO2, H2O, and release of energy
products of catabolism
CO2, H2O, energy release
anabolism
simple precursor molecules are built up into complex molecules - lipids, proteins, nucleic acids
biosynthesis
requires energy
removal of electrons
oxidation
1st thermodynamic law
energy may be changed/transported, but cannot be created/destroyed
2nd thermodynamic law
in any natural process, the entropy (disorder) of the universe increases
"heat death" of the universe
there is always a loss of useful energy (G) and an increase in unusable energy (heat) and entropy (S), while total energy stays the same
pathways used to form acetyl-CoA for CAC (4)
1) glycolysis
2) -oxidation
3) urea cycle
4) amino acid degradation
what makes ATP so stable?
even during removal of a phosphate, charge repulsion is reduced, leading to both molecules moving from a higher to a lower energy state (large -G)
important high energy thioester
acetyl-CoA
2 central features of metabolism
1) phosphoryl group transfers
2) electron transfer
how chemotrophs obtain energy
from the oxidation of molecules such as glucose or FAs
final acceptor of electrons
O2
how are electrons transferred?
via pyridine nucleotides
molecule that is reducing-agent/reductant
electron-donating molecule
molecule that is the oxidizing agent/oxidant
electron-accepting molecule
what NAD+ & NADP+ are derived from
niacin
____ (NAD+/NADH) is the electron acceptor.
NAD+
____ (NADP/NADPH) is the electron acceptor.
NADP
what NAD stands for
nicotinamide adenine dinucleotide
reaction by which ethanol is broken down
redox
molecules such as NAD+, NADP+, and FAD are ______ during catabolism.
reduced (gain electrons)
the 3 stages of energy extraction
1) acetyl-CoA production (glycolysis)
2) acetyl-CoA oxidation (TCA)
3) electron transfer & oxphos
3 levels of metabolic regulation
1) [regulatory enzymes]
2) catalytic activities of various enzymes (allosteric regulation, covalent modification)
3) relative levels of ATP, ADP, AMP
starting components of energy extraction (3)
1) carbohydrates
2) proteins
3) fats
carbohydrates are predominantly...
cyclized polyhydroxyl aldehydes or ketones
empiric formula of many (but not all) carbohydrates
(CH2O)n
2 common hexoses
1) glucose (aldohexose)
2) fructose (ketohexose)
pentose components of nucleic acids (2)
1) D-ribose (aldopentose)
2) 2-deoxy-D-ribose (aldopentose)
monosaccharides are ____ (chiral/achiral).
chiral
-D-glucopyranose OR -D-glucose
-D-glucopyranose OR -D-glucose
what kind of significant bond do disaccharides contain?
glycosidic bond
components of lactose
galactose & glucose
components of sucrose
glucose & fructose
components of trehalose
2 glucose
describe the structure of starch
unbranched, (1->4)-linked D-glucose
describe the structure of glycogen
polymer of (1->4)-linked subunits of glucose, with (1->6)-linked branches
effects of glycogen branches (2)
1) increase solubility of glycogen
2) involved in regulation of glycogen breakdown
stored fuel in animal cells
glycogen
where glycogen is found (2)
liver
skeletal muscle
if K'eq >1, G'o is ___ and the reaction proceeds ___.
negative (-); forward
if K'eq =1, G'o is ___ and the reaction proceeds ____.
0; is at equilibrium
if K'eq <1, G'o is ____ and the reaction proceeds ____.
positive (+); in reverse
(formula): G'o =
G'o = -RT ln K'eq
(formula): Keq=Ka=
units of Ka
1/Molar
=
OR
Gibbs free energy thermodynamics has a direct relationship to the speed of the
reaction. True or False?
FALSE
What value can we find when =0.5?
Kd
is equivalent to Vo. True or false?
TRUE
Kd
ligand concentration ([L]) at which P is half saturated
1/Ka
Which has the stronger affinity: Anti-HIV Immunoglobulin (Kd = 4x10-10M) or
Calmodulin (Kd = 3x10-6M)?
Anti-HIV Ig
(larger negative exponent, higher affinity)
Author
daynuhmay
ID
243201
Card Set
PHRD5025 Biochem Lecture 9 (Bain) - Chemical Logic & Thermodynamics