CHM 635 First Midsem, Spring 2012 Each question is worth 10 points 1. (a) What produces proton motive force in the mitochondria? (4 points) Proton motive force can be described as the storing of energy as a combination of a proton and voltage gradient acr
Most free purines and pyrimidines are salvaged, however some are catabolized Birds, reptiles and primates (including humans) convert purines to uric acid
Separation of base from (deoxy) ribose
Purine-nucleoside phosphorylase (PNP) sepa
UDP-glucose DNA, RNA NAD+, NADP+, FMN, FAD, Coenzyme A cAMP, cGMP
Nucleotide biosynthetic pathways are tremendously important as intermediate points for therapeutic agents. Many cancer drugs block steps in nucleo
Fatty Acid Catabolism
Occurs in Mitochondria
After uptake from the bloodstream, catabolism of the fatty acid requires three steps: 1) Activation of the fatty acid to a fatty acyl CoA 2) Uptake into mitochondria 3) Degradation (-oxidation)
Final exam May 2nd 1-3 pm
Fatty Acid Metabolism
fatty acid with a cis-9 double bond
A 16-C fatty acid with numbering conventions is shown. Most naturally occurring fatty acids have an even number of carbon atoms. The pathway f
Cancer and Glycolysis
Gatenby & Gillies Nature 2004, 891.
A near universal property of primary and metastatic cancers is upregulation of glycolysis.
The mediastinal nodes (purple arrow) and supraclavicular nodes (green arrows) show high uptake of 18flu
The Four Electron-Transport Complexes are Independent
Cytochrome c oxidase Catalyzes a four-electron reduction of molecular oxygen (O2) to water (H2O) Source of electrons is cytochrome c (links Complexes III and IV) Cytochrome c oxidase utiliz
Go' = -nFEo'
Electron transport chain (ETC)
Series of sequential oxidation/reduction (redox) reactions Finally see role of oxygen Passes electrons from NADH or FADH2 to O2 producing H2O through a series of protein complexes (source of metabolic water!)
Overview of catabolism
Entry of Pyruvate into the Mitochondrion
(Transition reaction occurs in mitochondria)
Pyruvate translocase transports pyruvate into the mitochondria in symport with H+
The transition reaction connects glycolys
Glycogen Synthesis and Degradation are controlled by Reciprocal Regulation
Glycogen Degradation and Synthesis are reciprocally regulated
1. Phosphorylase is regulated by allosteric interactions and phosphorylation. 2. Glycogen syntha
Allosterically inhibited by AMP and Fructose 2,6-bisphosphate.
Glucose-6-Phosphatase converts glucose-6-P to Glucose in the Endoplasmic Reticulum
Presence of G-6-Pase in ER of liver and kidney cells makes gluconeogenesis possible Mu
11.4 Free-Energy Changes in Glycolysis
Actual free-energy changes (G) large only for: #1 (hexokinase) #3 (phosphofructokinase) #10 (pyruvate kinase)
These steps are metabolically irreversible, and these enzymes are regulated G for all other steps are cl
Major pathways of glucose utilization
Why Glucose ?
1. Complete oxidation of glucose to carbon dioxide and water proceeds with a standard free-energy change of ~2,840 kJ/mol. 2. Storage as starch or glycogen. 3. When demands increases, glucose c
Biochemistry: Dynamic Aspects
Metabolism: An Overview Glycolysis The Tricarboxylic Acid Cycle Electron Transport Chain and Oxidative Phosphorylation Gluconeogenesis, Glycogen Metabolism and Pentose Phosphate Pathway Fatty Acid Metabolism Lipid
CHM 635 Biochemistry: Dynamic Aspects
T/TH 1:30-2:45 pm, BRWN 3102 Dr. Kavita Shah (5170D, BRWN) Email: [email protected] Office hours: 3:30-4:30 pm on Monday Biochemistry Garrett and Grisham 4th Edition
There will be
Chm 635 Quiz-I (Spring 2011) 1. Provide the pathway by which lactose can enter glycolysis. Lactose Lactase Glucose + Galactose (5 points)
Glucose enters glycolysis by forming Glucose-6-phosphate.
2. How the regulation of muscle phosphorylase differs from
Chm 635: Quiz 2 1. Draw the structure of triacyl glycerol (2 points).
2. How are dietary triacyl glycerol transported to adipose tissues? (5 points)
3. How are fatty acids metabolized in peroxisomes? (3 points)
4. Provide the committed step of fatty acid