scholarly journals A hydrogen dependent geochemical analogue of primordial carbon and energy metabolism

2019 ◽  
Author(s):  
Martina Preiner ◽  
Kensuke Igarashi ◽  
Kamila B. Muchowska ◽  
Mingquan Yu ◽  
Sreejith J. Varma ◽  
...  
Keyword(s):  
Hydrothermal Vents ◽  
Hydrogen Gas ◽  
Last Universal Common Ancestor ◽  
Acetyl Coa ◽  
Universal Common Ancestor ◽  
Acetyl Coa Pathway ◽  
Aqueous Conditions ◽  
Metal Cofactors ◽  
Alkaline Hydrothermal Vents ◽  
Electrochemical Potentials

AbstractHydrogen gas, H2, is generated in alkaline hydrothermal vents from reactions of iron containing minerals with water during a geological process called serpentinization. It has been a source of electrons and energy since there was liquid water on the early Earth, and it fuelled early anaerobic ecosystems in the Earth’s crust1–3. H2is the electron donor for the most ancient route of biological CO2fixation, the acetyl-CoA (or Wood-Ljungdahl) pathway, which unlike any other autotrophic pathway simultaneously supplies three key requirements for life: reduced carbon in the form of acetyl groups, electrons in the form of reduced ferredoxin, and ion gradients for energy conservation in the form of ATP4,5. The pathway is linear, not cyclic, it releases energy rather than requiring energy input, its enzymes are replete with primordial metal cofactors6,7, it traces to the last universal common ancestor8and abiotic, geochemical organic syntheses resembling segments of the pathway occur in hydrothermal vents today9,10. Laboratory simulations of the acetyl-CoA pathway’s reactions include the nonenzymatic synthesis of thioesters from CO and methylsulfide11, the synthesis of acetate12and pyruvate13from CO2using native iron or external electrochemical potentials14as the electron source. However, a full abiotic analogue of the acetyl-CoA pathway from H2and CO2as it occurs in life has not been reported to date. Here we show that three hydrothermal minerals — awaruite (Ni3Fe), magnetite (Fe3O4) and greigite (Fe3S4) — catalyse the fixation of CO2with H2at 100 °C under alkaline aqueous conditions. The product spectrum includes formate (100 mM), acetate (100 μM), pyruvate (10 μM), methanol (100 μM), and methane. With these simple catalysts, the overall exergonic reaction of the acetyl-CoA pathway is facile, shedding light on both the geochemical origin of microbial metabolism and on the nature of abiotic formate and methane synthesis in modern hydrothermal vents.

scholarly journals Metals enable a non-enzymatic acetyl CoA pathway

2017 ◽  
Author(s):  
Sreejith J. Varma ◽  
Kamila B. Muchowska ◽  
Paul Chatelain ◽  
Joseph Moran
Keyword(s):  
Carbon Fixation ◽  
Acid Synthesis ◽  
Last Universal Common Ancestor ◽  
Amino Acid Synthesis ◽  
Evolutionary Origins ◽  
Universal Common Ancestor ◽  
Wide Range ◽  
Biological Conversion ◽  
Acetyl Coa Pathway ◽  
Late Invention

The evolutionary origins of carbon fixation, the biological conversion of CO2to metabolites, remain unclear. Phylogenetics indicates that the AcCoA pathway, the reductive fixation of CO2to acetyl and pyruvate, was a key biosynthetic route used by the Last Universal Common Ancestor (LUCA) to build its biochemistry. However, debate exists over whether CO2fixation is a relatively late invention of pre-LUCA evolution or whether it dates back to prebiotic chemistry. Here we show that zero-valent forms of the transition metals known to act as co-factors in the AcCoA pathway (Fe0, Ni0, Co0) fix CO2on their surface in a manner closely resembling the biological pathway, producing acetate and pyruvate in near mM concentrations following cleavage from the surface. The reaction is robust over a wide range of temperatures and pressures with acetate and pyruvate constituting the major products in solution at 1 bar of CO2and 30 °g;C. The discovered conditions also promote 7 of the 11 steps of the rTCA cycle and amino acid synthesis, providing a stunning direct connection between simple inorganic chemistry and ancient CO2-fixation pathways. The results strongly sup-port the notion that CO2-fixation pathways are an outgrowth of spontaneous geochemistry.

scholarly journals SepF is the FtsZ anchor in archaea, with features of an ancestral cell division system

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Nika Pende ◽  
Adrià Sogues ◽  
Daniela Megrian ◽  
Anna Sartori-Rupp ◽  
Patrick England ◽  
...  
Keyword(s):  
Cell Division ◽  
Common Ancestor ◽  
Phylogenetic Analyses ◽  
Super Resolution ◽  
Binding Mode ◽  
Last Universal Common Ancestor ◽  
Division Plane ◽  
Multiple Factors ◽  
Universal Common Ancestor ◽  
Super Resolution Microscopy

AbstractMost archaea divide by binary fission using an FtsZ-based system similar to that of bacteria, but they lack many of the divisome components described in model bacterial organisms. Notably, among the multiple factors that tether FtsZ to the membrane during bacterial cell constriction, archaea only possess SepF-like homologs. Here, we combine structural, cellular, and evolutionary analyses to demonstrate that SepF is the FtsZ anchor in the human-associated archaeon Methanobrevibacter smithii. 3D super-resolution microscopy and quantitative analysis of immunolabeled cells show that SepF transiently co-localizes with FtsZ at the septum and possibly primes the future division plane. M. smithii SepF binds to membranes and to FtsZ, inducing filament bundling. High-resolution crystal structures of archaeal SepF alone and in complex with the FtsZ C-terminal domain (FtsZCTD) reveal that SepF forms a dimer with a homodimerization interface driving a binding mode that is different from that previously reported in bacteria. Phylogenetic analyses of SepF and FtsZ from bacteria and archaea indicate that the two proteins may date back to the Last Universal Common Ancestor (LUCA), and we speculate that the archaeal mode of SepF/FtsZ interaction might reflect an ancestral feature. Our results provide insights into the mechanisms of archaeal cell division and pave the way for a better understanding of the processes underlying the divide between the two prokaryotic domains.

scholarly journals A Deeply Branching Thermophilic Bacterium with an Ancient Acetyl-CoA Pathway Dominates a Subsurface Ecosystem

PLoS ONE ◽  
2012 ◽  
Vol 7 (1) ◽  
pp. e30559 ◽  
Author(s):  
Hideto Takami ◽  
Hideki Noguchi ◽  
Yoshihiro Takaki ◽  
Ikuo Uchiyama ◽  
Atsushi Toyoda ◽  
...  
Keyword(s):  
Thermophilic Bacterium ◽  
Acetyl Coa ◽  
Acetyl Coa Pathway

scholarly journals Origin of Life

2021 ◽  
Vol 83 (2) ◽  
pp. 76-79
Author(s):  
Cristina Sousa
Keyword(s):  
Origin Of Life ◽  
Common Ancestor ◽  
Scientific Evidence ◽  
Recent Common Ancestor ◽  
Last Universal Common Ancestor ◽  
Most Recent Common Ancestor ◽  
Universal Common Ancestor ◽  
The Origin Of Life

The origin of life is one of the most interesting and challenging questions in biology. This article discusses relevant contemporary theories and hypotheses about the origin of life, recent scientific evidence supporting them, and the main contributions of several scientists of different nationalities and specialties in different disciplines. Also discussed are several ideas about the characteristics of the most recent common ancestor, also called the “last universal common ancestor” (or LUCA), including cellular status (unicellular or community) and homogeneity level.

scholarly journals The extended reductive acetyl-CoA pathway: ATPases in metal cluster maturation and reductive activation

2014 ◽  
Vol 395 (5) ◽  
pp. 545-558 ◽  
Author(s):  
Jae-Hun Jeoung ◽  
Sebastian Goetzl ◽  
Sandra Elisabeth Hennig ◽  
Jochen Fesseler ◽  
Christina Wörmann ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Metal Cluster ◽  
Potential Gradient ◽  
Reductive Activation ◽  
Acetyl Coa ◽  
Oxygen Sensitive ◽  
Metal Organic ◽  
Acetyl Group ◽  
Acetyl Coa Pathway ◽  
Atp Binding And Hydrolysis

Abstract The reductive acetyl-coenzyme A (acetyl-CoA) pathway, also known as the Wood-Ljungdahl pathway, allows reduction and condensation of two molecules of carbon dioxide (CO2) to build the acetyl-group of acetyl-CoA. Productive utilization of CO2 relies on a set of oxygen sensitive metalloenzymes exploiting the metal organic chemistry of nickel and cobalt to synthesize acetyl-CoA from activated one-carbon compounds. In addition to the central catalysts, CO dehydrogenase and acetyl-CoA synthase, ATPases are needed in the pathway. This allows the coupling of ATP binding and hydrolysis to electron transfer against a redox potential gradient and metal incorporation to (re)activate one of the central players of the pathway. This review gives an overview about our current knowledge on how these ATPases achieve their tasks of maturation and reductive activation.

Sign in / Sign up

Export Citation Format

Share Document