The surprising pairing of 2-aminoimidazo[1,2-a][1,3,5]triazin-4-one, a component of an expanded DNA alphabet

Abstract

Supporting information: this article has supporting information at journals.iucr.org/cThe surprising pairing of 2-aminoimidazo[1,2-a]- [1,3,5]triazin-4-one, a component of an expandedSynthetic biologists demonstrate their command over natural biology by reproducing the behaviors of natural living systems on synthetic biomolecular platforms. For nucleic acids, this is being done stepwise, first by adding replicable nucleotides to DNA, and then removing its standard nucleotides. This challenge has been met in vitro with 'six-letter' DNA and RNA, where the Watson-Crick pairing 'concept' is recruited to increase the number of independently replicable nucleotides from four to six. The two nucleobases most successfully added so far are Z and P, which present a donor-donor-acceptor and an acceptor-acceptordonor pattern, respectively. This pair of nucleobases are part of an 'artificially expanded genetic information system' (AEGIS). The Z nucleobase has been already crystallized, characterized, and published in this journal . Acta Cryst. C72, 952-959]. More recently, variants of Taq polymerase have been crystallized with the pair P:Z trapped in the active site. Here we report the crystal structure of the nucleobase 2-aminoimidazo[1,2-a][1,3,5]triazin-4-one (trivially named P) as the monohydrate, C 5 H 5 N 5 OÁH 2 O. The nucleobase P was crystallized from water and characterized by X-ray diffraction. Interestingly, the crystal structure shows two tautomers of P packed in a Watson-Crick fashion that cocrystallized in a 1:1 ratio. research papers 28 Laos et al. A component of an expanded DNA alphabet Acta Cryst. (2019). C75, 22-28 supporting information sup-1 Acta Cryst. (2019). C75, 22-28 supporting information Acta Cryst. (2019). C75, 22-28 [https://doi.

Synthesis, Characterization, and X-ray Crystallography, of the First Cyclohexadienyl Trifluoromethyl Metal Complex (η5-C6H7)Fe(CO)2CF3

“…Moreover, the close contacts between particular atom types can be highlighted in so-called resolved fingerprint plots, [ 29 ] which allows the facile assignment of an intermolecular contact to a certain type of interaction and quantitatively summarize the nature and type of intermolecular contacts. The Hirshfeld surfaces are mapped with d norm , d e , and 2D fingerprint plots presented were generated using Crystal-Explorer 17.5 [ 32 , 33 , 34 , 35 , 36 ]. As can be seen from the results of the contact analysis, presented in Figure 3 and summarized in Table 1 , H-X interactions account for 84.8% of all contacts, signifying a highly compact solid-state structure.…”

Probing the electronic relaxation pathways and photostability of the synthetic nucleobase Z via laser interfaced mass spectrometry

“…1. 22,23 In order to gain insight into the physical properties of the protonated Z nucleobase, we have investigated the relative energetics of the different protomeric forms of ZÁH + using electronic structure methods. The three lowest-energy ZÁH + protomers, optimised at the MP2/cc-pVTZ level of theory, are shown in Fig.…”

“…18,19 Indeed, studies of Z:P have shown that this UBP closely mimics G:C in terms of geometry and stability, 20,21 as well as displaying excellent replication by cellular components. 22,23 All of these features indicate that the Z:P pair has excellent potential for future biotechnology applications. Furthermore, the presence of the unique NO 2 group functionality of Z may offer selective recognition by proteins, hence facilitating novel clinical applications.…”

Resolving Ultrafast Photoinitiated Dynamics of the Hachimoji 5‐aza‐7‐deazaguanine Nucleobase: Impact of Synthetically Expanding the Genetic Alphabet†

“…Similar atomic substitution has previously been shown to dramatically influence the photochemical and photophysical properties of a DNA or RNA molecule (21,44–49). Importantly, the WC base edge is maintained and has been shown to HB with its Hachimoji conjugate base 6‐amino‐5‐nitro‐2‐pyrimidinone (Z) (18,22,43,50).…”