Formation of amino acid precursors with large molecular weight in dense clouds and their relevance to origins of bio-homochirality

AbstractA wide variety of organic compounds have been found in carbonaceous chondrites and comets, which suggests that extraterrestrial organic compounds could have been an important source of the first terrestrial biosphere. In the Greenberg model, these organic compounds in the small bodies were originally formed in interstellar dusts (ISD) in dense clouds by the action of cosmic rays and ultraviolet light. We irradiated a frozen mixture of methanol, ammonia and water with high-energy heavy ions from an accelerator (“HIMAC” in NIRS, Japan) to simulate the action of cosmic rays in dense clouds. Racemic mixtures of amino acids were detected after hydrolysis of the irradiation products. A mixture of carbon monoxide, ammonia and water also gave such complex amino acid precursors with large molecular weights. When such amino acid precursors were irradiated with circular polarized UV light from a synchrotron, enantiomeric excesses were detected. The yield of amino acids was not largely changed between, before, and after CPL-irradiation. The present results suggest that the seed of homochirality of terrestrial amino acids were originally formed in interstellar space.

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Synthesis of Complex Organic Compounds from Simple Precursors: Formation of Amino-Acids, Amino-Acid Polymers, Fatty Acids and Purines from Ammonium Cyanide

Nature ◽

10.1038/199219a0 ◽

1963 ◽

Vol 199 (4890) ◽

pp. 219-222 ◽

Cited By ~ 126

Author(s):

C. U. LOWE ◽

M. W. REES ◽

R. MARKHAM

Keyword(s):

Amino Acids ◽

Fatty Acids ◽

Amino Acid ◽

Organic Compounds ◽

Amino Acid Polymers ◽

Complex Organic ◽

Ammonium Cyanide

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Plasma essential amino acids concentrations of early lactating Holstein dairy cows fed diet containing raw or roasted Iranian soybean

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200020858 ◽

2007 ◽

Vol 2007 ◽

pp. 182-182

Author(s):

Forouzan Tabatabaie ◽

Hassan Fathi ◽

Mohsen Danesh

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Dairy Cows ◽

Physical Method ◽

Essential Amino Acids ◽

High Energy ◽

Early Lactation ◽

High Amino Acid ◽

Amino Acid Requirements ◽

Physical Treatments

Whole soybean has 40-42 percent CP and used as high energy-protein supplement for early lactation dairy cows. However, the protein is highly degradable, so small amounts of amino acids can be reached to small intestine to meet high amino acid requirements of early lactating cows. Therefore, various chemical and physical treatments have been suggested to decrease ruminal protein degradability of soybeans. The practical use and application of any one method to lower ruminal feed degradability is dependent not only on its efficacy but also on its cost effectiveness, safety and ease of application. For these reasons, heat treatment is the most commonly used physical method (Plegge et al., 1985). The purpose of this study was to determine how roasting of soybeans affect plasma essential amino acid concentrations in early lactation cows.

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AMINO ACIDS IN THE BLOOD AND URINE OF NORMAL AND ARTHRITIC SUBJECTS BEFORE AND AFTER A GLYCINE LOAD GIVEN WITH AND WITHOUT ADRENOCORTICOTROPIN

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y57-116 ◽

1957 ◽

Vol 35 (1) ◽

pp. 1005-1016 ◽

Cited By ~ 3

Author(s):

J. B. Derrick ◽

Audrey P. Hanley

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Chromatographic Analysis ◽

Free Amino ◽

Serum Levels ◽

Essential Amino Acids ◽

Single Amino Acid ◽

Normal Individuals ◽

Before And After ◽

Serum And Urine

Observations have been made on the specific free amino acids (chromatographic analysis) and other nitrogenous constituents in the serum and urine of normal and arthritic men under controlled dietary conditions, before and after a glycine load and adrenocorticotropin administered separately and together.Differences in the metabolism of amino acids between normal individuals and arthritics, particularly of alanine, proline, glutamic acid, taurine, and possibly tyrosine (and/or tryptophan) and cystine, were apparent. The differences were largely confined to the non-essential amino acids. Concomitant increases seen in the serum levels and in the excretion of several amino acids, in response to a load of a single amino acid, indicate that the increases in excretion are more than a matter of competition for reabsorption in the kidney. A prerenal phenomenon appears to be involved, possibly interconversion of amino acids. This concept is supported by the evidence that the increases in the serum levels were restricted to the non-essential amino acids.

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Amino Acids Sequence Based in Silico Analysis of RuBisCO (Ribulose-1,5 Bisphosphate Carboxylase Oxygenase) Proteins in Some Carthamus L. ssp.

Notulae Scientia Biologicae ◽

10.15835/nsb9210053 ◽

2017 ◽

Vol 9 (2) ◽

pp. 204-208 ◽

Cited By ~ 1

Author(s):

Emre SEVİNDİK

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Average Length ◽

3D Structure ◽

Three Dimensional ◽

In Silico Analysis ◽

Bisphosphate Carboxylase ◽

Molecular Weights ◽

Acid Ratio ◽

Important Enzyme

RuBisCO is an important enzyme for plants to photosynthesize and balance carbon dioxide in the atmosphere. This study aimed to perform sequence, physicochemical, phylogenetic and 3D (three-dimensional) comparative analyses of RuBisCO proteins in the Carthamus ssp. using various bioinformatics tools. The sequence lengths of the RuBisCO proteins were between 166 and 477 amino acids, with an average length of 411.8 amino acids. Their molecular weights (Mw) ranged from 18711.47 to 52843.09 Da; the most acidic and basic protein sequences were detected in C. tinctorius (pI = 5.99) and in C. tenuis (pI = 6.92), respectively. The extinction coefficients of RuBisCO proteins at 280 nm ranged from 17,670 to 69,830 M-1 cm-1, the instability index (II) values for RuBisCO proteins ranged from 33.31 to 39.39, while the GRAVY values of RuBisCO proteins ranged from -0.313 to -0.250. The most abundant amino acid in the RuBisCO protein was Gly (9.7%), while the least amino acid ratio was Trp (1.6 %). The putative phosphorylation sites of RuBisCO proteins were determined by NetPhos 2.0. Phylogenetic analysis revealed that RuBisCO proteins formed two main clades. A RAMPAGE analysis revealed that 96.3%-97.6% of residues were located in the favoured region of RuBisCO proteins. To predict the three dimensional (3D) structure of the RuBisCO proteins PyMOL was used. The results of the current study provide insights into fundamental characteristic of RuBisCO proteins in Carthamus ssp.

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AMINO ACIDS IN THE BLOOD AND URINE OF NORMAL AND ARTHRITIC SUBJECTS BEFORE AND AFTER A GLYCINE LOAD GIVEN WITH AND WITHOUT ADRENOCORTICOTROPIN

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o57-116 ◽

1957 ◽

Vol 35 (11) ◽

pp. 1005-1016 ◽

Cited By ~ 3

Author(s):

J. B. Derrick ◽

Audrey P. Hanley

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Chromatographic Analysis ◽

Free Amino ◽

Serum Levels ◽

Essential Amino Acids ◽

Single Amino Acid ◽

Normal Individuals ◽

Before And After ◽

Serum And Urine

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Composition and Galactic Confinement of Cosmic Rays

Highlights of Astronomy ◽

10.1017/s1539299600000873 ◽

1971 ◽

Vol 2 ◽

pp. 740-756

Author(s):

Maurice M. Shapiro

Keyword(s):

Cosmic Rays ◽

Cosmic Ray ◽

High Energy ◽

Galactic Cosmic Rays ◽

Interstellar Space ◽

Heavy Nuclei ◽

High Energy Astrophysics ◽

Transit Times ◽

The Galaxy ◽

Path Lengths

The ‘Galactic’ cosmic rays impinging on the Earth come from afar over tortuous paths, traveling for millions of years. These particles are the only known samples of matter that reach us from regions of space beyond the solar system. Their chemical and isotopic composition and their energy spectra provide clues to the nature of cosmic-ray sources, the properties of interstellar space, and the dynamics of the Galaxy. Various processes in high-energy astrophysics could be illuminated by a more complete understanding of the arriving cosmic rays, including the electrons and gamma rays.En route, some of theprimordialcosmic-ray nuclei have been transformed by collision with interstellar matter, and the composition is substantially modified by these collisions. A dramatic consequence of the transformations is the presence in the arriving ‘beam’ of considerable fluxes of purely secondary elements (Li, Be, B), i.e., species that are, in all probability, essentially absent at the sources. We shall here discuss mainly the composition of the arriving ‘heavy’ nuclei -those heavier than helium - and what they teach us about thesourcecomposition, the galactic confinement of the particles, their path lengths, and their transit times.

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Synthesis of Amino Acid Precursors from Simulated Interstellar Media by High-Energy Particles or Photons

IEEJ Transactions on Electronics Information and Systems ◽

10.1541/ieejeiss.127.293 ◽

2007 ◽

Vol 127 (3) ◽

pp. 293-298 ◽

Cited By ~ 1

Author(s):

Kensei Kobayashi ◽

Tomoya Ogawa ◽

Hisako Tonishi ◽

Takeo Kaneko ◽

Yoshinori Takano ◽

...

Keyword(s):

Amino Acid ◽

High Energy ◽

Interstellar Media ◽

Amino Acid Precursors ◽

High Energy Particles

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Comparison of some properties of soil humic acids and synthetic phenolic polymers incorporating amino derivaties

Soil Research ◽

10.1071/sr9660041 ◽

1966 ◽

Vol 4 (1) ◽

pp. 41 ◽

Cited By ~ 46

Author(s):

JN Ladd ◽

JHA Butler

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Acid Hydrolysis ◽

Humic Acids ◽

Gel Filtration ◽

Quinone Imine ◽

Peptide Bonds ◽

Molecular Weights ◽

Soil Humic Acids ◽

Properties Of Soil

Twenty-three model phenolic polymers, either nitrogen-free or incorporating amino acids, peptides, or proteins, have been prepared from p-benzoquinone and catechol under mild oxidative conditions. Two lines of experimentation have demonstrated properties of soil humic acids closely similar to those of polymers incorporating proteins, but different from those of polymers incorporating amino acids: (1) fractionation of humic acids and synthetic polymers by 'Sephadex' gel filtration showed that the percentage of components of molecular weights nominally greater than 100 000 ranged from 52-76 % for eight humic acids tested, 53-59 % for benzoquinone-protein polymers (excluding polymers containing protamine), but less than 20% for all other polymers; (2) acid hydrolysis with 6M HCl resulted in a partial release of polymer nitrogen. Amino acid nitrogen in the hydrolysates accounted for 32.4-51.9 % of humic acid nitrogen, 31.2-56.3 % of the nitrogen of polymers incorporating protein, but less than 10.8% of the nitrogen of polymers incorporating individual amino acids. Experiments with model monomeric N-phenylglycine derivatives and with polymers incorporating simple peptides showed that the bond between the carbon atom of an aromatic ring and the nitrogen atom of an a-amino acid is far more stable to acid hydrolysis than peptide bonds or bonds linking amino acids in humic acids. Glycine is, however, readily released from N-phenylglycine derivatives when conditions favour their oxidation to a quinone-imine intermediate. Incorporation of proteins into phenolic polymers prevented the detection of peptide bonds by the Folin reagent.

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Protein degradation and synthesis measured with multiple amino acid tracers in vivo

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1996.271.4.e733 ◽

1996 ◽

Vol 271 (4) ◽

pp. E733-E741 ◽

Cited By ~ 3

Author(s):

P. Tessari ◽

R. Barazzoni ◽

M. Zanetti ◽

M. Vettore ◽

S. Normand ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Protein S ◽

Essential Amino Acids ◽

Body Protein ◽

Amino Acid Availability ◽

Before And After ◽

Branched Chain ◽

Multiple Amino Acid

Whether tracers of different essential amino acids yield the same estimates of body protein turnover is still uncertain. Therefore, we have simultaneously determined leucine (Leu; using [14C]Leu), phenylalanine (Phe; using [13C]Phe), and tyrosine (Tyr; using [2H2]Tyr) rates of appearance (Ra) from proteolysis (PD), as well as Leu and Phe disposal, into protein synthesis (PS) both before and after an anabolic stimulus in healthy volunteers. Protein anabolism was stimulated by insulin plus a branched-chain amino acid-enriched aromatic amino acid-deficient amino acid solution, which increased Leu (from 145 +/- 9 to 266 +/- 10 mumol/l) but decreased Phe (from 57 +/- 2 to 46 +/- 3) and Tyr (from 58.7 +/- 5.5 to 21.0 +/- 2.2) concentrations. Postabsorptive endogenous Leu Ra (2.04 +/- 0.12 mumol.kg-1.min-1), Phe Ra (0.66 +/- 0.03), and Tyr Ra (0.45 +/- 0.06), as well as rates of PS determined with the leucine (1.65 +/- 0.10 mumol.kg-1.min-1) and the phenylalanine tracer (0.57 +/- 0.03), agreed well with the known abundance of these amino acids in body protein(s). After insulin and amino acids, PD was suppressed (P < 0.001) using all tracers. However, although percent suppression of endogenous Leu Ra (-->1.49 +/- 0.10 mumol.kg-1.min-1, 26 +/- 5%) and Phe Ra (-->0.53 +/- 0.02 mumol.kg-1.min-1, -20 +/- 2%) were comparable, endogenous Tyr Ra was suppressed to a larger extent (-->0.23 +/- 0.02 mumol.kg-1.min-1, -46 +/- 3% P = 0.038). PS was stimulated using the Leu (+24 +/- 7%, P < 0.02) but not the Phe (+6 +/- 4%, not significant) data. We conclude that isotopes of different essential amino acid: provide comparable estimates of PD and PS in the postabsorptive state. However, their responses to an anabolic stimulus may differ, possibly depending on exogenous amino acid availability and/or the resulting plasma levels.

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