GEN MICROBIOLOGY BIOL 2051
Popular in Course
Popular in Biological Sciences
This 10 page Class Notes was uploaded by Charles Kohler on Tuesday October 13, 2015. The Class Notes belongs to BIOL 2051 at Louisiana State University taught by K. Sullivan in Fall. Since its upload, it has received 16 views. For similar materials see /class/222793/biol-2051-louisiana-state-university in Biological Sciences at Louisiana State University.
Reviews for GEN MICROBIOLOGY
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/13/15
Chapter 13 Energetics amp Catabolism Chapter 14 Respiration Lithotrophy amp Photolysis Sun is ultimate energy source Photosynthesis 7 Captures light stores it as chemical energy Heterotrophy 7 Uses captured chemical energy 7 Builds other chemicals Waste 7 Each step gives off heat energy so heat is lost Metabolism Catabolism 7 Breaking down moleculesinto similar molecules for energy Anabolism 7 Using energy to m cell components Metabolism 7 Balance between catabolism and anabolism 7 Central biochemical pathways used for both TCA cycle glycolysis pentose phosphate shunt Don t have to memorize the diagram below W A w 7m 9 W 4 A 4 M J Eleckan mner MW saute af ce u ar energy xmsfenedfmm an substance m mum cmung may 7 Passage afelectmns releases emxgy Requreselectxm danm andsamelype ufsubstancethansanelemm accepmx Execuannmmrmmmcms 7 Dx mm aanmsmpm Electmnenzrgycanbestared 39axlatexme pmpmymn 5mg mg 13 57mm mm We may um Na mum am 9 mm meded Phnyhnle addedvudehyniahan 7 Rexuseamhyaaxyas ATP most common sometimes GTP Metabolism Reduced geological Sunlight com pounds rocks Reduced biological Majoren gy inorganiccompounds macromolecules mama starch fats First energy 5 oueee Energy source f animals Phototropny Lithatrophy Organotrophy CATABOLISRN ANABOLISM Longterm Energy energy storage I Shortterm Blosynthesis ener ora e 9y y Carbon nitrogen ATP water Catalysis and Enzymes Activation energy energy required to bring all molecules in a chemical reaction into the reaction state so it s the energy needed to breaks bonds 39 Enzymes catalytic proteins speed up biochemical reaction rates by lowering activation Active site portion of an enzyme to Which substrate binds Substrate quot9 products substrate being converted to product by a speci c enzyme aldolas e Fructose16bisphosphate 9 g1yceraldehyde3 phosphate dihydroxyacetone phosphate 39 Veg speci c for their substrate Cellulose vs starch example Both made of glucose subunits but they have different linkages 39 Enzymes can have small protein molecules that help in catalysis but aren t part of the enzyme or the substrate Two types Ofwhat l Prosthetic groups bound tightly to their enzyme usually covalently and permanently Example heme group in cytochromes 2 Coenzymes loosely bound to their enzyme may associate with different enzymes usually derivatives of vitamins Example NAD derivative of niacin 39 Enzymes are named either for the substrate they bind or for the chemical reaction they catalyze with the addition of the suffix ase 39 For example cellulose breaks down cellulose into glucose hydrolases break various chemical bonds with the addition of water Catabolism The Microbial Buffet Microbes have great catabolic diversity 7 Electron donors Lithotrophy inorganic molecules Organotrophy organic molecules Phototrophy use light energy to reduce compounds then use these as electron donor 7 Electron acceptors Respiration inorganic molecules Fermentation organic molecules of organisms are fermenators they use organic molecules OxidationReduction o Oxidationreduction redox reactions involve the transfer of electron from electron donor to electron acceptor this generates enery it think 39 Electrons can t exist alone so for every oxidation there must also be a reduction In a redox reaction the substance oxidized is the electron donor the substance reduced is the electron acceptor Can involve transfer of both an electron and a proton H oxidation may involve addition of O or removal of H 9 didn t make notecard for this NAD as a Redox Electron Carrier In a cell the transfer of electrons from donor to acceptor typically involves one or more electron carriers not a direct transfer from electon donor to acceptor need things to help Electron carriers can be membrane bound prosthetic groups like cytochrome don t move out of CM C Freely diffusible like NAD nicotinamide adenine dinucleotide or NADP NADphosphate NADNADH 7 involved in energy generating catabolic reactions NADPNADPH involved in biosynthetic anabolic reactions Coenzymes like NAD and NADPH act as intermediaries between a prima electron donor and terminal electron acceptor that would not normallv be a redox couplegdon t get this part EnergyRich Compounds and Energy Storage The energy released in redox reactions is conserved in the formation of compounds with energyrich bondsthis is one of the ways that energy is stores The most common of these is adenosine triphosphate ATP main energy carrier in the cell Cleavage of each phosphanhydride bond releases free energy ATP ADP AMP Derivatives of coenzyme A have thioester bonds that release free energy upon hydrolysis Longterm storage of energy involves polymers such as glycogen and polyB hydroxybutyrate which can be consumers to yield ATP Major Catabolic Pathways Electron Transport and the Proton Motive Force Energy Conservation Options 1 Fermentation simplest way organisms can grow 2 Respiration a little more complicated 3 Photophosphorlation more like respiration Fermentation amp Respiration 7 two mechanisms for energy conservations in chemoorganotrophs In both synthesis of ATP is driven by energy released in oxidationreduction reactions but the reactions and mechanisms for each differ In fermentation there are no exogenous outside electron acceptors electron acceptor must be derived from electron donor In respiration molecular oxygen or other terminal electron acceptors that are just present in the environment so the cell doesn t have to make them they are already there Respiration can occur without oxygen In fermentation ATP is produced by substratelevel phosphorlation during catabolism of an organic compound Substrate level phosphorylation a phosphate group is added to an intermediate in a biochemical pathway and is eventually transferred to ADP to form ATP Respiration ATP is produced by both susbstrate level phosophorlation and oxidative phosophoraltion which is the biggest way Oxidative phosphorylation ATP is synthesized by a proton forve generated by redox reactions Requires enzyme ATP synthase which uses proton motive force to produce ATP from ADP Photophosphorylation method of producing ATP in photosynthetic organisms Similar to oxidative phosphorylation except light rather than a chemical compound drives the redox reaction that generate the proton motive force GlycolysisEmbdenMeyerhof pathway Major pathway of glucose metabolism Series of reactions in which each molecule of glucose is oxidized to 2 molecules of pyruvate with small amount of energy ATP being generated 1 glucose 2 pyruvate 2 ATP 2 NADH Enzymatic pathways Series of reactions used by organisms to convert one compound into another Each reaction is catalyzed by an enzyme See Fig 1317 Insert glycolysis diagram here look over Precursor metabolites made in glycolysis no notecard 39 glucose6phosphate fructose6phosphate glyceraldehyde3phosphate 3phosphoglycerate phosphoenolpyruvate Pyruvate Precursor metabolites compounds used to make all the macromolecules in the cell GlycolysisEmbdenMeyerhof pathway summary Glucose is oxidized to 2 molecules of pyruvate Net gain of 2 ATP 6 precursor metabolites are made NADH is formed which will be converted back to NAD in the electron transport system or in fermentation reaction At this point pyruvate can either be used in fermentation to form fermentation productsalcohols acids gases OR in respiration TCA cycle to be fully oxidized to carbon dioxide this makes more ATP so if an organism has a choice they ll choose respiration Fermentation vs Respiration Fermentation 7 from 1 glucose molecule 2 ATP are produced 7 partial oxidation of glucose 7 reduction of fermentation products NAD Respiration 7 from 1 glucose molecule 38 ATP are produced 7 complete oxidation of glucose all the way to C02 7 oxidation of pyruvate by citric acid cycle 7 uses electron transport system and ATPase 7 in both glycolsis occurs what happens to the pyruvate is different in each Fermentation didn t make notecards for this part 39 During fermentation glycolsis occurs followed by fermentation reactions No citric acid cycle no proton motive force During glycolysis electrons from glucose are passed to NAD which becomes NADH In fermentation electrons from NADH are passed to pyruvate regenerating NAD amp glycolsis can continue In this process total of 4 ATP are made by substrate level phosphorlation Then fermentation reactions take place Types of fermentation did for this though 2 most common types 1 Homolactic fermentation once electrons from NADH are passed to pyruvate pyruvate is reduced to lactic acid Ex Lactobacillus ferments the sugar in milk to produce lactic acid this gives us yogurt 2 Alcoholic fermentation once electrons are passed from NADH to pyruvate pyruvate is reduced to alcohol and C02 didn t Ex Yeast ferment the sugar in malted grains to produced alcohol and C02 beer In both types of fermentation the electron donor is glucose and electron acceptor is pyruvate which is made from glucose didn t make memorize Fermentation energy generating process where one organic compound ex glucose serves as the electron donor and a product of that compound serves as the electron acceptor expyruvate which is made from glucose Alcohole fermentation glucose92 pyruvic acid by glycoiscs didn t do this yet Respiration Some chemoheterotrophs can use oxygen or other compounds from the environment to accept the electron from NADH If electron acceptor is oxygen process is called aerobic respiration If electron acceptor is other compound from environment process is called anaerobic respiration anaerobic respiration and fermentation are totally different final electron acceptor may be an inorganic compound such as nitrate ferric iron sulfate or carbonate In fermentation the final electron acceptor is made by the cell from the electron donor ex Pyruvate made from glucose In respiration the final electron acceptor is a compound found in the environment ex Some compound from the environment oxygen or nitrogen The tricarboxylic acid TCA cycle aka Kreb s cycle citric acid cycle cyclic pathway used to fully oxidize organic materials like acetyl CoA End products ATP NADH and FADH2 important fused in ETC C02 waste product so not used as anything Precursor metabolites important Occurs during respiration not fermentation 7 Cell Need to eliminate pyruvate in fermentation its converted in reoperation not 7 OXidizes it completely to C02 Only possible with inorganic electron acceptor present in the environmentoxygen or nitrate Respiration produces more energy than fermentation so better If organism has a choice go w reoperation Fermentation only when no inorganic electron acceptor in the environment that is present Pyruvate dehydrgenase complex 7 Converts pyruvate to acetylCoA 39 Substrate for TCA is acetyl CoA made by removing C02 from pyruvate not pyruvate 39 Precursor metabolites made in TCA cycle Alphaketoglutarate amp oxaloacetate used to make amino acids amp nucleotides Reactions of the TCA cycle 39 Acetyl CoA oxaloacetate citrate 6 carbon compound 39 During this cycle acetyl CoA is oxidized to C02 amp original oxaloacetate is regenerated released NADH and FADH are generated precursor metabolites are made to be used for biosynthesis this is the end product of TCA See Fig 1327 Aromatic Catabolism Bacteria can degrade many compounds 7 PseudomonasRh0dococcus Aromatic compounds converted to p uvate so they start With mgvate 7 Allows growth in Wide range of environments 7 Used for bioremediation Cleaning up oil spill add bacteria to some of the oil and the bacterial degrade the oil very quickly they eat it Cleaning industrial sites Degrading toxic compounds
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'