skip to main content


Title: Concurrent Prebiotic Formation of Nucleoside‐Amidophosphates and Nucleoside‐Triphosphates Potentiates Transition from Abiotic to Biotic Polymerization
Abstract

Polymerization of nucleic acids in biology utilizes 5′‐nucleoside triphosphates (NTPs) as substrates. The prebiotic availability of NTPs has been unresolved and other derivatives of nucleoside‐monophosphates (NMPs) have been studied. However, this latter approach necessitates a change in chemistries when transitioning to biology. Herein we show that diamidophosphate (DAP), in a one‐pot amidophosphorylation‐hydrolysis setting converts NMPs into the corresponding NTPs via 5′‐nucleoside amidophosphates (NaPs). The resulting crude mixture of NTPs are accepted by proteinaceous‐ and ribozyme‐polymerases as substrates for nucleic acid polymerization. This phosphorylation also operates at the level of oligonucleotides enabling ribozyme‐mediated ligation. This one‐pot protocol for simultaneous generation of NaPs and NTPs suggests that the transition from prebiotic‐phosphorylation and oligomerization to an enzymatic processive‐polymerization can be more continuous than previously anticipated.

 
more » « less
NSF-PAR ID:
10303402
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
61
Issue:
1
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract

    Polymerization of nucleic acids in biology utilizes 5′‐nucleoside triphosphates (NTPs) as substrates. The prebiotic availability of NTPs has been unresolved and other derivatives of nucleoside‐monophosphates (NMPs) have been studied. However, this latter approach necessitates a change in chemistries when transitioning to biology. Herein we show that diamidophosphate (DAP), in a one‐pot amidophosphorylation‐hydrolysis setting converts NMPs into the corresponding NTPs via 5′‐nucleoside amidophosphates (NaPs). The resulting crude mixture of NTPs are accepted by proteinaceous‐ and ribozyme‐polymerases as substrates for nucleic acid polymerization. This phosphorylation also operates at the level of oligonucleotides enabling ribozyme‐mediated ligation. This one‐pot protocol for simultaneous generation of NaPs and NTPs suggests that the transition from prebiotic‐phosphorylation and oligomerization to an enzymatic processive‐polymerization can be more continuous than previously anticipated.

     
    more » « less
  2. Abstract

    A mechanism of nucleoside triphosphorylation would have been critical in an evolving “RNA world” to provide high‐energy substrates for reactions such as RNA polymerization. However, synthetic approaches to produce ribonucleoside triphosphates (rNTPs) have suffered from conditions such as high temperatures or high pH that lead to increased RNA degradation, as well as substrate production that cannot sustain replication. Previous reports have demonstrated that cyclic trimetaphosphate (cTmp) can react with nucleosides to form rNTPs under prebiotically‐relevant conditions, but their reaction rates were unknown and the influence of reaction conditions not well‐characterized. Here we established a sensitive assay that allowed for the determination of second‐order rate constants for all four rNTPs, ranging from 1.7×10−6to 6.5×10−6 M−1 s−1. The ATP reaction shows a linear dependence on pH and Mg2+, and an enthalpy of activation of 88±4 kJ/mol. At millimolar nucleoside and cTmp concentrations, the rNTP production rate is sufficient to facilitate RNA synthesis by both T7 RNA polymerase and a polymerase ribozyme. We suggest that the optimized reaction of cTmp with nucleosides may provide a viable connection between prebiotic nucleotide synthesis and RNA replication.

     
    more » « less
  3. Abstract

    Organophosphates were likely an important class of prebiotic molecules. However, their presence on the early Earth is strongly debated because the low availability of phosphate, which is generally assumed to have been sequestered in insoluble calcium and iron minerals, is widely viewed as a major barrier to organophosphate generation. Herein, we demonstrate that cyanide (an essential prebiotic precursor) and urea‐based solvents could promote nucleoside phosphorylation by transforming insoluble phosphate minerals in a “warm little pond” scenario into more soluble and reactive species. Our results suggest that cyanide and its derivatives (metal cyanide complexes, urea, ammonium formate, and formamide) were key reagents for the participation of phosphorus in chemical evolution. These results allow us to propose a holistic scenario in which an evaporitic environment could concentrate abiotically formed organics and transform the underlying minerals, allowing significant organic phosphorylation under plausible prebiotic conditions.

     
    more » « less
  4. Abstract

    Organophosphates were likely an important class of prebiotic molecules. However, their presence on the early Earth is strongly debated because the low availability of phosphate, which is generally assumed to have been sequestered in insoluble calcium and iron minerals, is widely viewed as a major barrier to organophosphate generation. Herein, we demonstrate that cyanide (an essential prebiotic precursor) and urea‐based solvents could promote nucleoside phosphorylation by transforming insoluble phosphate minerals in a “warm little pond” scenario into more soluble and reactive species. Our results suggest that cyanide and its derivatives (metal cyanide complexes, urea, ammonium formate, and formamide) were key reagents for the participation of phosphorus in chemical evolution. These results allow us to propose a holistic scenario in which an evaporitic environment could concentrate abiotically formed organics and transform the underlying minerals, allowing significant organic phosphorylation under plausible prebiotic conditions.

     
    more » « less
  5. null (Ed.)
    Abstract The RNA World is one of the most widely accepted hypotheses explaining the origin of the genetic system used by all organisms today. It proposes that the tripartite system of DNA, RNA, and proteins was preceded by one consisting solely of RNA, which both stored genetic information and performed the molecular functions encoded by that genetic information. Current research into a potential RNA World revolves around the catalytic properties of RNA-based enzymes, or ribozymes. Well before the discovery of ribozymes, Harold White proposed that evidence for a precursor RNA world could be found within modern proteins in the form of coenzymes, the majority of which contain nucleobases or nucleoside moieties, such as Coenzyme A and S-adenosyl methionine, or are themselves nucleotides, such as ATP and NADH (a dinucleotide). These coenzymes, White suggested, had been the catalytic active sites of ancient ribozymes, which transitioned to their current forms after the surrounding ribozyme scaffolds had been replaced by protein apoenzymes during the evolution of translation. Since its proposal four decades ago, this groundbreaking hypothesis has garnered support from several different research disciplines and motivated similar hypotheses about other classes of cofactors, most notably iron-sulfur cluster cofactors as remnants of the geochemical setting of the origin of life. Evidence from prebiotic geochemistry, ribozyme biochemistry, and evolutionary biology, increasingly supports these hypotheses. Certain coenzymes and cofactors may bridge modern biology with the past and can thus provide insights into the elusive and poorly-recorded period of the origin and early evolution of life. 
    more » « less