Example: bachelor of science

Systems Microbiology - MIT OpenCourseWare

THERMODYNAMICS OF GROWTH -contTHERMODYNAMICS OF GROWTH -cont dd APPLICATIONS of MICROBIAL APPLICATIONS of MICROBIAL CHEMOLITHOTROPHY & ANAEROBIC & ANAEROBIC MicrobiologyWeds Sept 20 - Ch 5 & Ch 17 (p 533-555) Bioenergetics & BASIC MODES OF ENERGY GENERATIONBASIC MODES OF ENERGY GENERATIONP hototrophs (Use Light as Energy Source )Photoautotrophs (Use CO2)Photoheterotrophs (Use Organic Carbon)Figure by MIT photoautotrophs utilize cyclicphotophosphorylationLightExcited electrons (2 e-)Electron transport chainEnergy for productionof ATPE lectron carrierCyclic PhotophosphorylationChlorophyllATPF igure by MIT OF DIVERSITY IN BACTERIAL ANOXYGENIC PHOTOTROPHS !+ + '(V) BacteriaGreen Sulfur BacteriaHeliobacteriaFdP870 NADHR everse electron flowQCytbc1 LightCytc2 BChlBPhLightLightFdP840 Chl aQQCytbc1 Cytc553 Cytc553P840P798 Chl a-OHFeSFeSCytbc1P798 Figure by MIT OCW.

Systems Microbiology Weds Sept 20 - Ch 5 & Ch 17 (p 533-555) ... microorganisms should exist. (And also the fact that if a bioenergetically favorable niche exists, a microbe will evolve ... Brock Biology of Microorganisms. 11th ed. Upper Saddle River, NJ: Pearson Prentice Hall, 2006. ISBN: 0131443291.

Tags:

  System, Microbiology, Microorganism, Biology, Brock, Mit opencourseware, Opencourseware, Systems microbiology

Information

Domain:

Source:

Link to this page:

Please notify us if you found a problem with this document:

Other abuse

Transcription of Systems Microbiology - MIT OpenCourseWare

1 THERMODYNAMICS OF GROWTH -contTHERMODYNAMICS OF GROWTH -cont dd APPLICATIONS of MICROBIAL APPLICATIONS of MICROBIAL CHEMOLITHOTROPHY & ANAEROBIC & ANAEROBIC MicrobiologyWeds Sept 20 - Ch 5 & Ch 17 (p 533-555) Bioenergetics & BASIC MODES OF ENERGY GENERATIONBASIC MODES OF ENERGY GENERATIONP hototrophs (Use Light as Energy Source )Photoautotrophs (Use CO2)Photoheterotrophs (Use Organic Carbon)Figure by MIT photoautotrophs utilize cyclicphotophosphorylationLightExcited electrons (2 e-)Electron transport chainEnergy for productionof ATPE lectron carrierCyclic PhotophosphorylationChlorophyllATPF igure by MIT OF DIVERSITY IN BACTERIAL ANOXYGENIC PHOTOTROPHS !+ + '(V) BacteriaGreen Sulfur BacteriaHeliobacteriaFdP870 NADHR everse electron flowQCytbc1 LightCytc2 BChlBPhLightLightFdP840 Chl aQQCytbc1 Cytc553 Cytc553P840P798 Chl a-OHFeSFeSCytbc1P798 Figure by MIT OCW.

2 + + + 2H12e- + + IPhotosystem IIE0(V)'LightP680 Cyclic electron flow(generates proton motive force)Noncyclicelectron flow(generates protonmotive force)FeSPcQBQ poolChl a0P680*NAD(P)HNAD(P)+P700 Cyt bfP700*FdFpQAPhQAPSIIPSIThe Z SchemeFigure by MIT in Live in hypersaline hypersaline habitatshabitatsAerial photograph of haloarchaea changing the colors of their saltwater habitats removed due to copyright by MIT +H+Glu-194 RetinalMicrobial rhodopsins fall into two main functional classesSensory rhodopsinsLight-driven ion pumpsFigure by MIT +Cl-HRHtrlHis-kinaseRegulatorRegulatorRe gulatorHis-kinasePPMethylation helicesSRllHtrllSRlFlagellar motorRhodopsin Functional DiversityCytoplasmBacteriorhodopsin and proteorhodospinLight driven proton pumpsHigh H+ concentrationOutside cellInside cellElectrons from NADH or chlorophyllADP+ PiLow H+ concentrationH+H+123 ATP}MembraneATPsynthaseElectron transport chain (includes)

3 Proton pumps)Figure by MIT by MIT interiorCell exteriorAsp-85 Arg-82 Asp-96 Glu-204H+H+Glu-194 RetinalImages and diagrams of various rhodopsins removed due to copyright Science 289 (September 15, 2000). et al., Environmental Genome ShotgunSequencing of the Sargasso Sea, Science 394:66-74 (2004) Many new bacterialproteorhodopsins discoveredin environmetnal shotgunsequencingDiagram removed due to copyright of a hybrid automobile, hydrocarbons, and electricity removed due to copyright ORGANISMS chemotrophsphototrophschemolithotrophsch emoorganotrophsWhere do organisms get their energy?Oxidize inorganic compoundsOxidize organic compoundsDerive energy from lightMICROBIALMICROBIALMETABOLIC METABOLIC DIVERSITYDIVERSITYR elative VoltageRelative VoltageREDUCTANTS (EAT) OXIDANTS (BREATHE)-10 - 8- 6- 4- 2 0+ 2 + 4+ 6+ 8+ 10+ 12+ 14-10 - 8- 6- 4- 2 0 + 2 + 4 + 6 + 8 + 10 + 12 + 14 OrganicCarbonCO2SO4=AsO43-FeOOHSeO3NO2-N O3-MnO2NO3-/N2O2H2H2 SSoFe(II)NH4+Mn(II)ABPhotoreductantsMicr obes can eat & breathe just about anything !

4 Diagrams removed due to copyright Figures 5-22a, 5-20, and 5-23 in Madigan, Michael, and John Martinko. brock biology of ed. Upper Saddle River, NJ: Pearson Prentice Hall, 2006. ISBN: (chemo [chemical], litho [rock], auto[self], troph [feeding])Energy source: inorganic substrates (H2, NH3, NO2-, H2S, Fe2+)Carbon source: CO2e- acceptor: O2(aerobes), or S(some anaerobes), Fe3+, NO3, SO4 Chemolithoautotrophs can be grouped according to the inorganic compounds that they oxidize for energy:Nitrifiers - Oxidize reduced Nitrogen compounds such as NH4+Sulfur Oxidizers- Oxidize reduced Sulfur compounds such as H2S, S0, and S2O-Iron Oxidizers- Oxidize reduced Iron-Fe2+ (ferrous iron)Hydrogen Oxidizers-Oxidize Hydrogen gas-H2 METABOLIC DIVERSITY - Continued.

5 Table of energy yields from the oxidation of various inorganic electron donors removed due to copyright restrictions. See Table 17-1 in Madigan, Michael, and John Martinko. brock biology of Microorganisms. 11th Saddle River, NJ: Pearson Prentice Hall, 2006. ISBN: DIVERSITYCHEMOLITHOAUTOTROPHS - ExamplesCHEMOLITHOTROPHIC AMMONIA OXIDATION - AEROBICNH4+ + 3/2O2 --> NO2- + H2O + 2H+NH2 OHNH2OH+ H2O+ H2O+ O2+ 2H+NH3H2OO2 + 4H+OO-N+5H+Oxidation of hydroxylamine2H+H+H+ADP + PiATP12 Oxidation of ammoniaReduction of oxygenHAOAMO4e-2e-Cyt cCyt cQCyt aa32e-2e-2e-PeriplasmFigure by MIT means "anaerobic ammonium oxidation". Anammox is both a new low-cost method ofN-removal in wastewater treatment, and a spectacular microbial way of life - woo - woo !

6 CHEMOLITHOTROPHIC AMMONIA OXIDATION - ANAEROBICC ourtesy of the Department of Microbiology at Radboud University Nijmegen. Used with permission. Eo= Eo (electron acceptor) - Eo (electron donor) = 1233 mV2NH4+/N2 half reaction (6e-) Eo = V2NO2-/N2 half reaction (6e-) Eo = + V Go=-nF Eo= -(3) ( kJ/Vmol)( ) = - 357 kJ/molBroda predicted, based solely on the thermodynamics, that suchmicroorganisms should exist. (And also the fact that if abioenergetically favorable niche exists, a microbe will evolveto fill it !).About a decade later, the bugs were discovered in bioreactorsstarted from waste water treatment removed due to copyright to conventionalnitrification/denitrificatio n, thismethod saves 100% of the carbonsource, & 50% of the requiredoxygen.

7 This leads to a reduction ofoperational costs of 90%, a decreasein CO2 emissions of more than 100%(the process actually consumes CO2),and a decrease in energy removed due to copyright restrictionsAnaerobic ammonium oxidation by anammox bacteria in the Black Sea Marcel M. M. Kuypers, A. Olav Sliekers, Gaute Lavik, Markus Schmid, Bo Barker J rgensen, J. Gijs Kuenen, Jaap S. Sinninghe Damst , Marc Strous and Mike S. M. Jetten. Nature 422, 608-611 (10 April 2003)Graphs removed due to copyright RESPIRATION =Dumping your electrons on something other than oxygen Denitrification = Use of NO3- as terminal electron acceptor, that resultsin complete conversion to N2 Figures 17-35 and 17-37 in Madigan, Michael, and John Martinko. brock biology of Microorganisms.

8 11th ed. Upper Saddle River, NJ: Pearson Prentice Hall, 2006. ISBN: removed due to copyright growing on iron oxidesCH3 COO-Fe3+e-Fe2+CO2 Anaerobic respirationImage of geobacter growing on iron oxides removed due to copyright Organic MatterHydrolysisFermentable SubstratesH2 AcetateMicrobial Competition for SubstratesOther low molecular weight organic acids}NO3- reducers Mn(IV) reducersFe(III) reducersSO42- reducersMethanogens}Organic Matter Degradation In Anaerobic EnvironmentsFermentationFigure by MIT removed due to copyright acceptor Go (using glucose)Oxygen-3190 kJ/molNO3--3030Mn (IV)-3090Fe(III)-1410 Sulfate-380CO2-350 From Nealson and Saffarini 1994 Energetic explains order: not all e-acceptors are equal!25 Complex Assemblage of Organic MatterHydrolysis into ConstituentsFermentable Sugars and Amino AcidsFermentation by a Fermentative Microbial ConsortiumAcetate and Minor ProductsAromatic CompoundsLong-Chain Fatty AcidFe3+ OxideFe2+Geobacter pathway for the anaerobic oxidation of organic matter to carbon dioxide with Fe3+ oxide serving as an electron acceptor in temperate, freshwater and sedimentary environments.

9 The process is mediated by a consortium of fermentative microorganisms and Geobacter by MIT reduction2 Fe(III) reductionMn(IV) reductionNO3 (IV) reductionAerobicGroundwater flow-High O2 Low O2 High organicsFigure by MIT distribution of terminal electron-accepting processes (TEAPs) observed within anaerobic portions of aquiferscontaminated with organic removed due to copyright Lovley, D. R., E. J. P. Phillips, Y. A. Gorby, and E. R. Landa. "Microbial Reduction of Uranium." Nature 350 (1991): respiration to clean up of uranium pollutionAcetate + U (VI) U (IV)s + CO2CH3C00- + 4 U(VI) U (IV)s + 2 HCO3- + 9H+Carried out by GeobacterExample of bioremediation Lovley DR, Phillips EJP, Gorby YA, Landa ER. Microbial Reduction of Uranium, 1991, (6317): mobile Insoluble, immobilePhotograph removed due to copyright removed due to copyright restrictions.

10 Diagram removed due to copyright restrictions. See Bond, Holmes, Tender, and Lovley. Science 295 (2002): and photograph of a sediment microbial fuel cell removed due to copyright between pilus current and applied voltage demonstrating the linear, ohmic, response characteristic of a true of the electronic connection of the AFM tip in a conducting probe atomic force microscope (CP-AFM). HOPG, highly oriented pyrolytic force microscope stageV=IRExtracellular electron transfer via microbial 2005 Jun 23;435(7045):1098-101. Good electron acceptors Good electron donorsPhotograph removed due to copyright restrictionsDNSSO42- SO42- Diffusion Sea FloorSeawaterMETHANE FLUXS ulfate Reduction ZoneABCDNSF igure by MIT NAEROBIC MMETHANE ETHANE OOXIDATIONXIDATIONG eochemical Observations:Geochemical Observations:CH4 + SO42- HCO3- + HS- + H2 OMicrobiologically ?


Related search queries