Drei Domänen des Lebens• Unterschiede auf zellularer und molekularer Ebene definieren drei unterschiedliche

"Domänen"

Three Domains of Life• Differences in cellular and molecular level define three distinct domains of life

Alle Zellen brauchen Kohlenstoff Konstruktionswerkstoff (1)

Alle Zellen brauchen Energie Aufrechterhaltung des Betriebs (2)

(1) Unterscheidung nach Kohlenstoffquelle CO2 oder org. Verbindungen

(2) Unterscheidung nach Energiequelle elektromagnetische Strahlung oder

energiereiche Verbindungen

(1) Autotrophe Heterotrophe

(2) Phototrophe Chemotrophe Lithotrophe

Organotrophe

Benutzen organische Nährstoffe aus organischen Kohlenstoffquellen.

Heterotrophe

Photo-HeterotropheEnergiequelle:

Licht

Chemo-heterotropheChemo-litho-heterotropheEnergiequelle: anorganische Oxidation

purple non-sulfur bacteria, green non-sulfur bacteria and heliobacteria

Nitrobacter spp., Wolinella (with H2 as reducing equivalent donor), some Knallgas-bacteria

Chemo-heterotropheChemo-organo-

heterotropheEnergiequelle: organische Oxidation (Kohlenstoffverbindungen)

Bauen organische Nährstoffe aus anorganischen Kohlenstoffquellen auf. Kohlenstoffquelle: CO2 (Atmosphäre, Wasser)

Autotrophe

Photo-AutotropheEnergiequelle:

Licht Photosynthese zum Aufbau der Nährstoffe

Chemo-autotrophenur: Litho-autotrophe

Energiequelle: anorganische Oxidation„Brennstoffe“: CH4,NH3, NH4

+, H2S, Fe2+, SO3

2- , NO2-, …

(alle oxidierbare Anorganik)Cyanobakteriengrüne Algengrüne Pflanzen die meisten Bacteria und Archaea

Lebende Systeme beziehen Energie• Aus dem Sonnenlicht

– Planzen– Grüne Bakterien– Cyanobakterien

• Aus Brennstoffen– Tiere– Die meisten Bakterien

• Die Energieaufnahme ist notwendig für den Erhalt der komplexen Strukturen und des dynamischen Gleichgewichts (steady state, stationärer Zustand), weit entfernt vom thermodynamischen Gleichgewichtszustand.

Living Systems Extract Energy• From sunlight

– plants– green bacteria– cyanobacteria

• From fuels– animals– most bacteria

• Energy input is needed in order to maintain complex structures and be in a dynamic steady state, away from the equilibrium

In chemistry, a steady state is a situation in which all state variables are constant in spite of ongoing processes that strive to change them. For an entire system to be at steady state, i.e. for all state variables of a system to be constant, there must be a flow through the system (compare mass balance). One of the most simple examples of such a system is the case of a bathtub with the tap open but without the bottom plug: after a certain time the water flows in and out at the same rate, so the water level (the state variable being Volume) stabilizes and the system is at steady state.

The steady state concept is different from chemical equilibrium. Although both may create a situation where a concentration does not change, in a system at chemical equilibrium, the net reaction rate is zero (products transform into reactants at the same rate as reactants transform into products), while no such limitation exists in the steady state concept. Indeed, there does not have to be a reaction at all for a steady state to develop.

In chemistry, a steady state is a situation in which all state variables are constant in spite of ongoing processes that strive to change them. For an entire system to be at steady state, i.e. for all state variables of a system to be constant, there must be a flow through the system (compare mass balance). One of the most simple examples of such a system is the case of a bathtub with the tap open but without the bottom plug: after a certain time the water flows in and out at the same rate, so the water level (the state variable being Volume) stabilizes and the system is at steady state.

The steady state concept is different from chemical equilibrium. Although both may create a situation where a concentration does not change, in a system at chemical equilibrium, the net reaction rate is zero (products transform into reactants at the same rate as reactants transform into products), while no such limitation exists in the steady state concept. Indeed, there does not have to be a reaction at all for a steady state to develop.

Solarenergie als die ultimative Quelle aller biologischer EnergieKooperation phototropher und heterotropher Zellen

Yearly Solar fluxes & Human Energy Consumption

Solar 3 850 000 EJWind 2250 EJBiomass 3000 EJPrimary energy use (2005) 487 EJElectricity (2005) 56.7 EJ

1 EJ (Exa) = 1018 J