Converting raw energy into biological energy

invoking respiration that is still ATP dependant (sic)

We define a molecular heat engine as a molecule that can convert heat into free energy when thermally cycled or when placed in a thermal gradient.A detailed model for a molecular heat engine is constituted by the pF1 enzyme, a proposed progenitor of the homologous (1) alpha and beta sub units of the F1 moiety of the contemporary ATP synthase enzyme (2-4). In the thermosynthesis model for the origin of life, pF1 synthesizes peptide and phosphate bonds by creating a local environment in its enzymatic cavity that permits dehydration reactions. The product containing the bond has a higher free energy in water (5), and can therefore, because of energy conservation, not directly be released. Instead, it remains strongly bound, entering the medium only upon a thermal unfolding of pF1. The binding change mechanism as effected by contemporary ATP synthase (6) is identified as a relic of this so-defined thermosynthesis mechanism.In the model the thermal cycling is attributed to - macroscopic - convection of the medium in which the pF1 is suspended.
Consider as example present day F1 ATP synthase as a heat engine. The presence of nucleotides increases its unfolding temperature by ~10C. The delta H for the unfolding of the individual alpha and beta subunits is ~660 kJ/mole (7-8). At an unfolding temperature of 60C (330K) the Carnot ratio predicts an available work of(delta T / T) delta H = (10 / 330) 660 = 20 kJ/mole,a value comparable with the free energy of a peptide and phosphate bond.Using only one enzyme to begin with, thermosynthesis by a molecular heat engine allows a very simple model for the emergence of the bioenergetic chemiosmotic machinery and, more generally, for the origin of life (2-4).

Abiotic formation of organic compounds under hydrothermal conditions is of interest to bio, geo-, and cosmochemists. Oceanic sulfur-rich hydrothermal systems have been proposed as settings for the abiotic synthesis of organic compounds. Carbon disulfide is a common component of magmatic and hot spring gases, and is present in marine and terrestrial hydrothermal systems. Thus, its reactivity should be considered as another carbon source in addition to carbon dioxide in reductive aqueous thermosynthesis. We have examined the formation of organic compounds in aqueous solutions of carbon disulfide and oxalic acid at 175 degrees C for 5 and 72 h. The synthesis products from carbon disulfide in acidic aqueous solutions yielded a series of organic sulfur compounds. The major compounds after 5 h of reaction included dimethyl polysulfides (54.5%), methyl perthioacetate (27.6%), dimethyl trithiocarbonate (6.8%), trithianes (2.7%), hexathiepane (1.4%), trithiolanes (0.8%), and trithiacycloheptanes (0.3%). The main compounds after 72 h of reaction consisted of trithiacycloheptanes (39.4%), pentathiepane (11.6%), tetrathiocyclooctanes (11.5%), trithiolanes (10.6%), tetrathianes (4.4%), trithianes (1.2%), dimethyl trisulfide (1.1%), and numerous minor compounds. It is concluded that the abiotic formation of aliphatic straight-chain and cyclic polysulfides is possible under hydrothermal conditions and warrants further studies.

Measurements of bacterial sulfate reduction and dissolved oxygen (O2) in hypersaline bacterial mats from Baja California, Mexico, revealed that sulfate reduction occurred consistently within the well-oxygenated photosynthetic zone of the mats. This evidence that dissimilatory sulfate reduction can occur in the presence of O2 challenges the conventional view that sulfate reduction is a strictly anaerobic process. At constant temperature, the rates of sulfate reduction in oxygenated mats during daytime were similar to rates in anoxic mats at night: thus, during a 24-hour cycle, variations in light and O2 have little effect on rates of sulfate reduction in these mats.

In the 1960s the NASA Exobiology Program began support for initial research on chemical evolution. This became a vigorous program, utilizing the concurrently evolving state-of-the-science expertise and instrumentation for analyses of organic matter in ancient terrestrial sediments, meteorites, and lunar samples ... Over the past 25 years, organic geochemistry has expanded into a myriad of research areas and has built a vast database for biomarkers indicative of biochemistry. This information is available to aid in the search for tracers of prebiotic organic chemistry and of extinct and extant life in samples from the solar system.The original term applied to chemical biomarkers was chemical fossils (Eglinton and Calvin, [1967]), which evolved to biological markers (Hunt, [1979]), and was then contracted to the currently popular term biomarker ... Biomarkers can also be identified (if present) in macro- and microfossils by comparing their molecular composition with that of the embedding sediment (Otto and Simoneit, [2001]). Amino acids and other labile biochemicals have been used as indicators or evidence for biological activity and preservation in the more recent geological record and in meteorites (Abelson, [1954]; Engel et al., [1993]; Mitterer, [1993]). Cyclic and branched hydrocarbons, acids, and heterocompounds (e.g., terpenoids) are generally stable over long periods, and thus are useful indicators of biosynthesis in the older geological record. The utility of biomarkers as indicators of biogenic, paleoenvironmental, and geochemical processes on Earth has been widely accepted (Mackenzie et al., [1982]; Johns, [1986]; Simoneit et al., [1986], and references therein; Brassell, [1992]; Imbus and McKirdy, [1993]; Mitterer, [1993]; Simoneit, [1998]).

The biomarker concept is illustrated herein with bacterial lipids that elucidate the development and evolution of oxygenic photosynthesis and aerobiosis, because these processes are at the heart of the modern carbon cycle and sustain complex life (Simoneit et al., [1998]; Summons et al., [1996]). Bacterial mats from modern hot springs (e.g., Yellowstone National Park) have lipid distributions with striking similarities to preserved hydrocarbons from the Proterozoic and Archean. Points of resemblance include abundant low molecular weight, linear and simple branched alkanes, acyclic isoprenoids such as phytenes and phytol, and carotenoids (Dobson et al., [1988]; Ward et al., [1989]; Shiea et al., [1990]; Zeng et al., [1992]

Here we argue that life emerged on Earth from a redox and pH front at c. 4.2 Ga. This front occurred where hot (c. 150C), extremely reduced, alkaline, bisulphide-bearing, submarine seepage waters interfaced with the acid, warm (c. 90C), iron-bearing Hadean ocean. The low pH of the ocean was imparted by the ten bars of CO2 considered to dominate the Hadean atmosphere/hydrosphere.Disequilibrium between the two solutions was maintained by the spontaneous precipitation of a colloidal FeS membrane. Iron monosulphide bubbles comprising this membrane were inflated by the hydrothermal solution upon sulphide mounds at the seepage sites.Our hypothesis is that the FeS membrane, laced with nickel, acted as a semipermeable catalytic boundary between the two fluids, encouraging synthesis of organic anions by hydrogenation and carboxylation of hydrothermal organic primers. The ocean provided carbonate, phosphate, iron, nickel and protons; the hydrothermal solution was the source of ammonia, acetate, HS, H2 and tungsten, as well as minor concentrations of organic sulphides and perhaps cyanide and acetaldehyde.The mean redox potential across the membrane, with the energy to drive synthesis, would have approximated to 300 millivolts. The generation of organic anions would have led to an increase in osmotic pressure within the FeS bubbles. Thus osmotic pressure could take over from hydraulic pressure as the driving force for distension, budding and reproduction of the bubbles.Condensation of the organic molecules to polymers, particularly organic sulphides, was driven by pyrophosphate hydrolysis.Regeneration of pyrophosphate from the monophosphate in the membrane was facilitated by protons contributed from the Hadean ocean. This was the first use by a metabolizing system of protonmotive force (driven by natural pH) which also would have amounted to c. 300 millivolts. Proton motive force is the universal energy transduction mechanism of life. Taken together with the redox potential across the membrane, the total electrochemical and chemical energy available for protometabolism amounted to a continuous supply at more than half a volt.The role of the iron sulphide membrane in keeping the two solutions separated was appropriated by the newly synthesized organic sulphide polymers. This organic take-over of the membrane material led to the miniaturization of the metabolizing system. Information systems to govern replication could have developed penecontemporaneously in this same milieu. But iron, sulphur and phosphate, inorganic components of earliest life, continued to be involved in metabolism.

It assumes a material cause before the evidence has spoken...

Scientists have been trying to find the origin of Earth's adenine and where else it might exist in the solar system. University of Missouri-Columbia researcher Rainer Glaser may have the answer ... "The idea that certain molecules came from space is not outrageous," said Glaser, professor of chemistry in MU's College of Arts and Science. "You can find large molecules in meteorites, including adenine. We know that adenine can be made elsewhere in the solar system, so why should one consider it impossible to make the building blocks somewhere in interstellar dust?"

In fact, the evidence that has been presented in this thread shows quite well that it is entirely possible that the energy conversion processes in the modern cell could have developed naturalistically.

A nearby resident, Jim Brook, found the first meteorite fragments while driving homewards on the ice of Taku Arm in Tagish Lake. What Brook had uncovered was an extraterrestrial clue from the early solar system, a 4.5-billion-year-old meteorite. To date, 500 more fragments have been found near Tagish Lake and hundreds have been recovered from the site - many still encased in ice.The delicate charcoal found on Tagish Lake indeed is a rare example of a meteor class called carbonaceous chondrites . an Australian space rock called the Murchison meteorite had captured such excitement and anticipation among meteor experts. That largely charcoal rock held some remarkable clues about how life might have begun, since the biochemistry showed signs of amino acids, the simple building blocks of proteins for cells.

The exogenous delivery of organic matter by asteroids, comets, and carbonaceous meteorites could have contributed to the early Earth’s prebiotic inventory by seeding the planet with biologically important organic compounds [1]. A wide variety of prebiotic organic compounds have previously been detected in the Murchison CM type carbonaceous chondrite including amino acids, purines and pyrimidines [2]. . Several purines including adenine, guanine, hypoxanthine, and xanthine, as well as the pyrimidine uracil, have previously been detected in water or formic acid extracts of Murchison .