Biochem Flashcards
Catalytic efficiency
Kcat/Km
Km
Substrate concentration at half vmax
Lock and key model
Enzyme specificity
Shape of michaelis menten
Hyperbolic
Competitive inhibition
Inhibitor competes for active site
Increase Km
Uncompetitive inhibition
Inhibitor binds ES
Decrease vmax
Decrease km
Non competitive inhibition
Inhibitor binds E and ES equally
Decrease vmax
Mixed inhibition
Inhibitor binds E and ES unequally
Increase or decrease Km
Decrease vmax
Axes on michaelis menten vs lineweaver burke
V vs (S) 1/V vs 1/(S)
Kcat
Vmax/ [E]
Hills coefficient
If greater than one, indicates cooperative binding
Slope and intercepts lineweaver burke
Slope km/vmax
Y int 1/vmax
Lineweaver for competitive inhibition
No change in y intercept, increasing slopes
Lineweaver for uncompetitive
Same slope increasing y intercept
Lineweaver for non competitive
Increasing slope and y intercept
Where does electron transport occur?
Where are H+ pumped into?
In the inner membrane of mitochondria
Pumped from mitochondrial matrix into the intermembrane space
ETC complexes and functions. how many protons do each pump?
NADH dehydrogenase (4) - oxidizes NADH Ubiquinone/coenzyme Q - oxidizes FADH2 Cytochrome C reductase (4) (Cytochrome C) Cytochrome C oxidase (2) - Turns O2 into H2O
How many Protons drive synthesis of one ATP?
4
pH gradient in mitochondria
High pH in the matrix, low in the inter membrane space
Products of glycolysis
Per glucose - 2 pyruvate, 2 NADH, 2 ATP
Products of pyruvate oxidation
Acetyl co A and NADH
Products of Krebs
Per pyruvate- 3 NADH, 1 FADH2, 1 GTP
Where does glycolysis occur? Krebs? Pyruvate oxidation?
Cytoplasm
Mitochondrial matrix
Mitochondrial matrix
How many ATP are generated from NADH and FADH2?
1 NADH from matrix - 2.5 ATP
1 FADH2 - 1.5 ATP
1 NADH from cytoplasm - 1.5 ATP
Total ATP yield prok vs euk?
30 euk
32 prok
Pentose phosphate pathway
Directs glucose 6 P away from glycolysis to make glycolytic intermediates
Main enzyme PPP
G6PDH
Oxidative and non oxidative phases of PPP
Oxidative- NADPH (reducing agent ), ribulose 5 phosphate (for nucleotide synthesis)
Non oxidative - glycolytic intermediates
Irreversible glycolytic enzymes and gluconeogenesis counterparts
Hexokinase/ glucose 6 phosphatase
PFK 1 / fructose 1 6 biphosphatase
Pyruvate kinase/ pyruvate carboxylase
+PEPCK
Amino acid molecular weight
110 kDa
Amino acids chirality
All chiral but glycine
All S configuration but cysteine
Kinetic vs thermodynamic control
Kinetic - smaller Ea, higher, less stable energy level overall
Thermo - more stable and preferred, but higher Ea required to reach that state
If a rxn is under kinetic control, the energy available is not high enough to surpass the Ea
