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J P Ferris

Publications and source records attributed to J P Ferris.

At least 19 recordsLinked to original sources
PubMed1992

Oligomerization of ribonucleotides on montmorillonite: reaction of the 5'-phosphorimidazolide of adenosine.

The regiospecific formation of oligomers from unblocked monomers in aqueous solution is one of the central tenets in research on the origins of life on earth. Direct experimental support for this hypothesis has been obtained in studies of the condensation of the 5'-phosphorimidazolide of adenosine (ImpA) with itself and with P1,P2-diadenosine-5',5'-pyrophosphate (AppA) in water in the presence of a montmorillonite clay. Oligomers of up to ten nucleotides in length are formed. Analysis of the trimers, tetramers, and pentamers formed from a 9:1 ImpA:AppA mixture has shown that 85% of the bonds formed are 3',5'-linked and that any 2',5'-linkages present are at the phosphodiester bond next to the 3'-terminus of the oligomers.

Adenosine Monophosphate↗
PubMed1989

Mineral catalysis of the formation of dimers of 5'-AMP in aqueous solution: the possible role of montmorillonite clays in the prebiotic synthesis of RNA.

The reaction of the 5'-AMP with water soluble carbodiimide (EDAC) in the presence of Na+-montmorillonite 22A results in the formation of 2',5'-(pA)2 (18.9%), 3',5'-(pA)2 (11%), and AppA (4.8%). When poly(U) is used in place of the clay the product yields are 2',5'-(pA)2 (15.5%), 3',5'-(pA)2 (3.7%) and AppA (14.9%). The 3',5'-cyclic dinucleotide, 3',5'-c(pA)2, is also formed when poly(U) is used. AppA is the principal reaction product when neither clay nor poly(U) is present in the reaction mixture. Products which contain the phosphodiester bond are formed at different ionic strengths, pH and temperatures using Na+-montmorillonite. Phosphodiester bond formation was not observed when Cu2+-montmorillonite was used or when DISN was used in the place of EDAC. The extent catalysis of phosphodiester bond formation varied with the particular clay mineral used. Those Na+-clays which bind 5'-AMP more strongly are better catalysts. Cu2+-montmorillonite, which binds 5'-AMP strongly, exhibits no catalytic activity.

Adenosine Monophosphate↗
PubMed1988

Montmorillonite: a multifunctional mineral catalyst for the prebiological formation of phosphate esters.

Reaction of diiminosuccinonitrile (DISN) with 3'-AMP in the presence of alkali- and alkaline earth-montmorillonites results in the formation of 2',3'-cAMP in aqueous solution. Little or no 2', 3'-cAMP is produced when metal ion concentrations equivalent to that of the metal ion associated with the homoionic clays are used instead of mobntmorillionite. Yields comparable to those obtained with DISN are obtained when diaminomaleonitrile (DAMN) is used in place of DISN as the condensing agent. DAMN, a compound which is more stable than DISN in aqueous solution, is oxidized to DISN on the surface of the clay by Fe+3 in the clay lattice. DISN, the true condensing agent, is thus generated in the presence of the bound 3'-AMP on the montmorillonite surface. The montmorillonite catalyzes the DISN-mediated formation of 2', 3'-cAMP and this product, which binds much less strongly than does the 3'-AMP, is desorbed from the clay surface. This research established that the montmorillonite performs four different functions in its role as catalyst: (1) Binding one of the substrate molecules (3'-AMP) (2) Activating the second substrate (DAMN) (3) Catalyzing the formation of 2', 3'-cAMP (4) Releasing the reaction product so another substrate molecules can bind to the montmorillonite.

Adenosine Monophosphate↗
PubMed1984

The prebiotic chemistry of nucleotides.

Diiminosuccinonitrile (DISN), formed by the oxidation of diaminomaleonitrile (DAMN), has been investigated as a potential prebiotic phosphorylating agent. DISN effects the cyclization of 3'-adenosine monophosphate to adenosine 2', 3'-cyclic phosphate in up to 39% yield. The mechanism of this reaction was investigated. The DISN-mediated phosphorylation of uridine to uridine monophosphate does not proceed efficiently in aqueous solution. The reaction of DISN with uridine-5'-phosphate and uridine results in the formation of 2,2'-anhydronucleotides and 2,2'-anhydronucleosides respectively, and other reaction products resulting from an initial reaction at the 2'- and 3'- hydroxyl groups. The clay mineral catalysis of the cyclization of adenosine-3'-phosphate was investigated using homoionic montmorillonites.

Chemical Phenomena↗
PubMed1979

The effect of clays on the oligomerization of HCN.

The reaction of 0.1 M HCN and dilute solutions of diaminomaleonitrile (DAMN) at pH 8--9 and 25 degrees C in the presence of suspensions of montmorillonite (bentonite) clays were investigated. Montmorillonite clays inhibit the oligomerization of aqueous solutions of HCN. Yields of colored oligomers, ura, and DAMN, are all diminished by clays, but the rate of loss of cyanide is not significantly decreased. The inhibition of oligomer formation is due to the clay-catalyzed decomposition of DAMN. The absence of strong binding of DAMN to clays was suggested by our failure to detect DAMN when a clay that had been incubated with DAMN was washed with spermidine (6 x 10(-3) g/liter). It was established that DAMN does not simply bind to the clays by the observation that the bulk of the radioactivity was recovered from the supernatant in the reaction of 14C-DAMN with montmorillonite. The clay-catalyzed decomposition of DAMN was observed when montmorillonite from two different sources was used and with a variety of homoinic montmorillonites and bentonites. A modification of the established procedure for using the cyanide electrode for cyanide analyses was used to follow the release of HCN from DAMN. This new method can be used in both the acidic and basic pH range and it does not result in the destruction of DAMN by the reagents used for the analysis. Quantitative analyses of the reaction solution from the clay-catalyzed decomposition of DAMN revealed the formation of 1--2 equivalents of HCN per mole of DAMN. The possible significance of these clay-catalyzed reactions in chemical evolution is discussed.

Bentonite↗
PubMed1978

HCN: a plausible source of purines, pyrimidines and amino acids on the primitive earth.

Dilute (0.1 M) solutions of HCN condense to oligomers at pH 9.2. Hydrolysis of these oligomers yields 4,5-dihydroxypyrimidine, orotic acid, 5-hydroxyuracil, adenine, 4-aminoimidazole-5-carboxamide and amino acids. These results, together with the earlier data, demonstrate that the three main classes of nitrogen-containing biomolecules, purines, pyrimidines and amino acids may have originated from HCN on the primitive earth. The observation of orotic acid and 4-aminoimidazole-5-carboxyamide suggests that the contemporary biosynthetic pathways for nucleotides may have evolved from the compounds released on hydrolysis of HCN oligomers.

Amino Acids↗
PubMed1977

Chemical evolution XXIX. Pyrimidines from hydrogen cyanide.

Dilute (0.1 M) solutions of HCN condense to oligomers at pH 8-9. Hydrolysis of these oligomers at pH 8.5 or with 6 N HCl yields 4,5-dihydroxypyrimidine, as the most abundant pyrimidine product along with orotic acid and 5-hydroxyuracil. These results, together with the earlier data, demonstrate that the three major nitrogen-containing classes of biomolecules could have originated from HCN on the primitive earth. The observation of the formation of orotic acid and 4-aminoimidazole-5-carboxamide by the hydrolysis of the HCN oligomers suggests that once the initially formed pyrimidines and purines were consumed, those life forms persisted which evolved enzymes for conversion of these intermediates to the pyrimidines and purines present in contemporary RNA.

Chemical Phenomena↗