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Rivas, M, Becerra A, Pereto J, Bada JL, Lazcano A.  2011.  Metalloproteins and the Pyrite-based Origin of Life: A Critical Assessment. Origins of Life and Evolution of Biospheres. 41:347-356.   10.1007/s11084-011-9238-1   AbstractWebsite

We critically examine the proposal by W chtersh user (Prokaryotes 1: 275-283, 2006a, Philos Trans R Soc Lond B Biol Sci 361: 787-1808, 2006b) that putative transition metal binding sites in protein components of the translation machinery of hyper-thermophiles provide evidence of a direct relationship with the FeS clusters of pyrite and thus indicate an autotrophic origin of life in volcanic environments. Analysis of completely sequenced cellular genomes of Bacteria, Archaea and Eucarya does not support the suggestion by W chtersh user (Prokaryotes 1: 275-283, 2006a, Philos Trans R Soc Lond B Biol Sci 361: 787-1808, 2006b) that aminoacyl-tRNA synthetases and ribosomal proteins bear sequence signatures typical of strong covalent metal bonding whose absence in mesophilic species reveals a process of adaptation towards less extreme environments.

Johnson, AP, Cleaves HJ, Dworkin JP, Glavin DP, Lazcano A, Bada JL.  2008.  The Miller volcanic spark discharge experiment. Science. 322:404-404.   10.1126/science.1161527   Website
Kminek, G, Bada JL, Botta O, Glavin DP, Grunthaner F.  2000.  MOD: an organic detector for the future robotic exploration of Mars. Planetary and Space Science. 48:1087-1091.   10.1016/s0032-0633(00)00082-9   AbstractWebsite

Searching for extinct or extant life on Mars is part of the future NASA surveyor class missions. Looking for key organic compounds that are essential for biochemistry as we know it or indicative of extraterrestrial organic influx is the primary goal of the Mars Organic Detector (MOD). MOD is able to detect amino acids, amines and PAHs with at least 100 times higher sensitivity than the Viking GCMS experiment. MOD is not capable of identifying specific organic molecules but can assess the organic inventory of amines and PAHs on the planet. MOD can also quantify adsorbed and chemisorbed water and evolved carbon dioxide in a stepped heating cycle to determine specific carbon-bearing minerals. All that comes with no sample preparation and no wet chemistry. The organics can be isolated from the carrier matrix by heating the sample and recovering the volatile organics on a cold finger. This sublimation technique can be used for extracting amino acids, amines and PAHs under Mars ambient conditions. The detection of amino acids, amines and PAHs is based on a fluorescence detection scheme. The MOD concept has functioned as a laboratory breadboard since 1998. A number of natural samples including shells, clays, bones, lambda -DNA and E.-coli bacteria have been used and organic molecules have been extracted successfully in each case. The first prototype of MOD is operational as of early fall of 1999. MOD has been selected for the definition phase of the NASA-MSR 2003 mission. (C) 2000 Elsevier Science Ltd. All rights reserved.

Hutt, LD, Glavin DP, Bada JL, Mathies RA.  1999.  Microfabricated capillary electrophoresis amino acid chirality analyzer for extraterrestrial exploration. Analytical Chemistry. 71:4000-4006.   10.1021/ac9903959   AbstractWebsite

Chiral separations of fluorescein isothiocyanate-labeled amino acids have been performed on a microfabricated capillary electrophoresis chip to explore the feasibility of using such devices to analyze for extinct or extant life signs in extraterrestrial environments. The test system consists of a folded electrophoresis channel (19.0 cm long x 150 mu m wide x 20 mu m deep) that was photolithographically fabricated in a 10-cm-diameter glass wafer sandwich, coupled to a laser-excited confocal fluorescence detection apparatus providing subattomole sensitivity. Using a sodium dodecyl sulfate/gamma-cyclodextrin pH 10.0 carbonate electrophoresis buffer and a separation voltage of 550 V/cm at 10 degrees C, baseline resolution was observed for Val, Ala, Glu, and Asp enantiomers and Gly in only 4 min. Enantiomeric ratios were determined for amino acids extracted from the Murchison meteorite, and these values closely matched values determined by HPLC. These results demonstrate the feasibility of using microfabricated lab-on-a-chip systems to analyze extraterrestrial samples for amino acids.

Bada, JL, Peterson RO, Schimmelmann A, Hedges REM.  1990.  Moose Teeth as Monitors of Environmental Isotopic Parameters. Oecologia. 82:102-106.   10.1007/bf00318540   Website
Bada, JL, Maynard JB, Luyendyk BP.  1970.  Marine Sediments - Dating by Racemization of Amino Acids. Science. 170:730-&.   10.1126/science.170.3959.730   Website