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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, Protsch R.  1973.  Racemization Reaction of Aspartic-Acid and Its Use in Dating Fossil Bones - (Olduvai Gorge 5,000-70,000-Years-Old Range Hominids). Proceedings of the National Academy of Sciences of the United States of America. 70:1331-1334.   10.1073/pnas.70.5.1331   Website
Bada, JL.  1985.  Aspartic-Acid Racemization Ages of California Paleoindian Skeletons. American Antiquity. 50:645-647.   10.2307/280327   Website
Bada, JL.  1998.  Biogeochemistry of organic nitrogen compounds. Nitrogen-Containing Macromolecules in the Bio- and Geosphere. 707( Stankiewicz BA, VanBergen PF, Eds.).:64-73., Washington: Amer Chemical Soc Abstract

Nitrogen containing organic compounds represent the second most abundant reservoir of nitrogen on the surface of the Earth. However, the organic compounds that make up this global nitrogen pool are not well characterized. Although amino acids and the nitrogenous bases of nucleic acids make up only a few percent of the total organic nitrogen reservoir, the geochemical reactions of these compounds have been extensively studied. Because hydrolysis reactions are rapid on the geologic time scale, both proteins and nucleic acids (DNA and RNA) are not preserved for more than 10(3) to 10(5) years in most environments. The racemization reaction of amino acids converts the L-amino acids present in the biosphere into a racemic mixture (D/L amino acid ratio = 1.0) in the geosphere in less than 10(6) years. Anhydrous conditions, such as those that may be associated with amber entombed insects, may retard both biopolymer hydrolysis and racemization. Condensation reactions between amino acids and sugars, including sugars at apurinic sites in nucleic acid fragments, likely result in the incorporation of these compounds into geopolymers such as humic acids. Although rearrangement reactions in geopolymers may scramble the original molecular structures, part of the global organic nitrogen inventory was originally derived from amino acids and nucleic acid bases.

Bada, JL, Miller SL.  1969.  Kinetics and Mechanism of Nonenzymatic Reversible Deamination of Aspartic Acid. Journal of the American Chemical Society. 91:3946-&.   10.1021/ja01042a047   Website
Bada, J.  1983.  Amino Acid Racemization dating of fossil bones from Zhouk. China Excahnge News. 11:4-6.
Bada, J, Herman B, Payan IL, Man E.  1989.   Amino Acid Racemization in bone and boiling of the german emperor Lothar I. Applied Geochemistry. 4
Bada, JL, Lazcano A.  2002.  Origin of life - Some like it hot, but not the first biomolecules. Science. 296:1982-1983.   10.1126/science.1069487   Website
Bada, JL.  1972.  Kinetics of Racemization of Amino-Acids as a Function of Ph. Journal of the American Chemical Society. 94:1371-&.   10.1021/ja00759a064   Website
Bada, JL, Miller SL.  1968.  Equilibrium Constant for Reversible Deamination of Aspartic Acid. Biochemistry. 7:3403-&.   10.1021/bi00850a014   Website
Bada, JL, Chalmers JH, Cleaves HJ.  2016.  Is formamide a geochemically plausible prebiotic solvent? Physical Chemistry Chemical Physics. 18:20085-20090.   10.1039/c6cp03290g   AbstractWebsite

From a geochemical perspective, significant amounts of pure formamide (HCONH2) would have likely been rare on the early Earth. There may have been mixed formamide-water solutions, but even in the presence of catalyst, solutions with >= 20 weight% water in formamide would not have produced significant amounts of prebiotic compounds. It might be feasible to produce relatively pure formamide by a rare occurrence of freezing formamide/water mixtures at temperatures lower than formamide's freezing point (2.55 degrees C) but greater than the freezing point of water. Because of the high density of formamide ice it would have sunk and accumulated at the bottom of the solution. If the remaining water froze on the surface of this ice, and was then removed by a sublimation-ablation process, a small amount of pure formamide ice might have been produced. In addition a recent report suggested that similar to 85 weight% formamide could be prepared by a geochemical type of fractional distillation process, offering another possible route for prebiotic formamide production.

Bada, JL.  1982.  Racemization of Amino-Acids in Nature. Interdisciplinary Science Reviews. 7:30-46.Website
Bada, JL, Zhao MX, Steinberg S, Ruth E.  1986.  Isoleucine Stereoisomers on the Earth. Nature. 319:314-316.   10.1038/319314a0   Website
Bada, J.  1984.  Application of Amino Acid Racemization Dating of Fossil Bones and Teeth in problems of paleoanthropology. McGraw-Hill yearbook of science and technology. :87-89.
Bada, JL.  2009.  Enantiomeric excesses in the Murchison meteorite and the origin of homochirality in terrestrial biology. Proceedings of the National Academy of Sciences of the United States of America. 106:E85-E85.   10.1073/pnas.0906490106   Website
Bada, J, Shou MY.  1980.  Kinetics and mechanics of amino acid racemization in aqueous solution and bones. Biogeochemistry of amino acids. Ed: Hare, P. E, Hoering, T. C, King, K.
Bada, JL.  1991.  Amino-Acid Cosmogeochemistry. Philosophical Transactions of the Royal Society of London Series B-Biological Sciences. 333:349-358.   10.1098/rstb.1991.0084   AbstractWebsite

Amino acids are ubiquitous components of living organisms and as a result they are widely distributed on the surface of the Earth. Whereas only 20 amino acids are found in proteins, a much more diverse mixture of amino acids has been detected in carbonaceous meteorites. Amino acids in living organisms consist exclusively of the L-enantiomers, but in meteorites, amino acids with chiral carbons are present as racemic mixtures. Protein amino acids undergo a variety of diagenetic reactions that produce some other amino acids but not the unique amino acids present in meteorites. Nevertheless, trace quantities of meteoritic amino acids may occur on the Earth, either as a result of bolide impact or from the capture of cosmic dust particles. The ensemble of amino acids present on the early Earth before life existed was probably similar to those in prebiotic experiments and meteorites. This generates a question about why the L-amino acids on which life is based were selected.

Bada, J.  2003.  Origins of life. Oceanography. 16:98-104.
Bada, JL, Protsch R, Schroede.Ra.  1973.  Racemization Reaction of Isoleucine Used as a Paleotemperature Indicator. Nature. 241:394-395.   10.1038/241394a0   Website
Bada, JL.  1985.  Amino-Acid Racemization Dating of Fossil Bones. Annual Review of Earth and Planetary Sciences. 13:241-268.   10.1146/   Website
Bada, JL, Glavin DP, McDonald GD, Becker L.  1998.  A search for endogenous amino acids in martian meteorite ALH84001. Science. 279:362-365.   10.1126/science.279.5349.362   AbstractWebsite

Trace amounts of glycine, serine, and alanine were detected in the carbonate component of the martian meteorite ALH84001 by high-performance liquid chromatography. The detected amino acids were not uniformly distributed in the carbonate component and ranged in concentration from 0.1 to 7 parts per million. Although the detected alanine consists primarily of the L enantiomer, low concentrations (<0.1 parts per million) of endogenous D-alanine may be present in the ALH84001 carbonates. The amino acids present in this sample of ALH84001 appear to be terrestrial in origin and similar to those in Allan Hills ice, although the possibility cannot be ruled out that minute amounts of some amino acids such as D-alanine are preserved in the meteorite.