Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Microbial Metabolism (Part 2) I. Objectives II. What does a
Document related concepts
Fatty acid metabolism wikipedia , lookup
Butyric acid wikipedia , lookup
Biosequestration wikipedia , lookup
Amino acid synthesis wikipedia , lookup
Biochemical cascade wikipedia , lookup
Evolution of metal ions in biological systems wikipedia , lookup
Photosynthesis wikipedia , lookup
Photosynthetic reaction centre wikipedia , lookup
Basal metabolic rate wikipedia , lookup
NADH:ubiquinone oxidoreductase (H+-translocating) wikipedia , lookup
Phosphorylation wikipedia , lookup
Nicotinamide adenine dinucleotide wikipedia , lookup
Light-dependent reactions wikipedia , lookup
Adenosine triphosphate wikipedia , lookup
Electron transport chain wikipedia , lookup
Biochemistry wikipedia , lookup
Microbial metabolism wikipedia , lookup
Citric acid cycle wikipedia , lookup
Transcript
Microbial Metabolism (Part 2) The life of a heterotroph Chapter 5: 122-136 I. Objectives How do heterotrophs obtain energy for cellular processes? – glycolysis – fermentation – aerobic respiration II. What does a heterotroph need? A. Carbon source B. Energy source 1 III: Starting with glucose A. Step 1 (5.12) – Glycolysis – Most common pathway Diagram of glycolysis B. Net result Net Result glucose + 2 ADP + 2 Pi + 2 NAD+ --> 2 pyruvate + 2 ATP + 2 (NADH + H+) C. Other early pathways Pentose phosphate pathway Entner-Doudoroff pathway 2 IV. Step 2: What to do next with energy extracted from glucose A. Small amount of ATP can be used directly. B. At the very least – Must regenerate NAD+ C. Solution 1: Fermentation 1. Lactic Acid Fermentation Pyruvate + NADH --> lactic acid + NAD+ Homolactic fermenters – Streptococcus – Lactobacillus Heterolactic fermenters – Lactobacillus – Leuconostoc 2. Alcoholic fermentation Two steps – pyruvate --> acetaldehyde + CO2 – acetaldehyde + NADH --> ethanol + NAD+ Examples: 3 D. Fermentation in review Roles in nature What substances can be fermented? V. A more efficient solution: Aerobic respiration A. Overall results B. How accomplished? C. Overall pathway 1. Glycolysis 2. Krebs cycle 3. Oxidative phosphorylation 4 D. Krebs Cycle (AKA: Citric Acid Cycle or TCA) 1. Net result E. Other sources of carbon for catabolism Carbohydrates Lipids Proteins 5 VI. What happens to energy stored in NADH? A. What is needed B. How it’s done – Oxidative phosphorylation C. What NADH is worth D. What will 52 kcal of energy get you? 1. Theoretical ATP synthesis 2. Actual ATP synthesis 3. How? VII. Oxidative phosphorylation A. First stage – 1. Electron transport from NADH to oxygen 6 2. Results in energy stored across membrane Generation of proton gradient – Animation of electron transport Net result: B. Second stage Chemiosmotic theory ADP + Pi --> ATP C. Inhibitors of Oxidative Phosphorylation Block electron transfer 7 Review of metabolic requirements for heterotrophs Source Source of energy of carbon An alternative IV. Anaerobic respiration Electron acceptor other than oxygen Most acceptors are inorganic Use ETS, proton gradient, ATP synthase 8 A. Nitrate (NO3-): denitrification B. Sulfate (SO42-) C. Carbon dioxide 9
