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Bulygin AA, Syryamina VN, Kuznetsova AA, Novopashina DS, Dzuba SA, Kuznetsov NA. Inner Amino Acid Contacts Are Key Factors of Multistage Structural Rearrangements of DNA and Affect Substrate Specificity of Apurinic/Apyrimidinic Endonuclease APE1. Int J Mol Sci 2023; 24:11474. [PMID: 37511233 PMCID: PMC10380840 DOI: 10.3390/ijms241411474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/10/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Apurinic/apyrimidinic endonuclease 1 (APE1) is one of the most important enzymes in base excision repair. Studies on this enzyme have been conducted for a long time, but some aspects of its activity remain poorly understood. One such question concerns the mechanism of damaged-nucleotide recognition by the enzyme, and the answer could shed light on substrate specificity control in all enzymes of this class. In the present study, by pulsed electron-electron double resonance (DEER, also known as PELDOR) spectroscopy and pre-steady-state kinetic analysis along with wild-type (WT) APE1 from Danio rerio (zAPE1) or three mutants (carrying substitution N253G, A254G, or E260A), we aimed to elucidate the molecular events in the process of damage recognition. The data revealed that the zAPE1 mutant E260A has much higher activity toward DNA substrates containing 5,6-dihydro-2'-deoxyuridine (DHU), 2'-deoxyuridine (dU), alpha-2'-deoxyadenosine (αA), or 1,N6-ethenoadenosine (εA). Examination of conformational changes in DNA clearly revealed multistep DNA rearrangements during the formation of the catalytic complex. These structural rearrangements of DNA are directly associated with the capacity of damaged DNA for enzyme-induced bending and unwinding, which are required for eversion of the damaged nucleotide from the DNA duplex and for its placement into the active site of the enzyme. Taken together, the results experimentally prove the factors that control substrate specificity of the AP endonuclease zAPE1.
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Affiliation(s)
- Anatoly A Bulygin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
| | - Victoria N Syryamina
- Institute of Chemical Kinetics and Combustion, Siberian Branch of Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
| | - Aleksandra A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
| | - Darya S Novopashina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
| | - Sergei A Dzuba
- Institute of Chemical Kinetics and Combustion, Siberian Branch of Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk 630090, Russia
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2
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Kinetic Features of 3'-5'-Exonuclease Activity of Apurinic/Apyrimidinic Endonuclease Apn2 from Saccharomyces cerevisiae. Int J Mol Sci 2022; 23:ijms232214404. [PMID: 36430884 PMCID: PMC9697762 DOI: 10.3390/ijms232214404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/22/2022] Open
Abstract
In yeast Saccharomyces cerevisiae cells, apurinic/apyrimidinic (AP) sites are primarily repaired by base excision repair. Base excision repair is initiated by one of two AP endonucleases: Apn1 or Apn2. AP endonucleases catalyze hydrolytic cleavage of the phosphodiester backbone on the 5' side of an AP site, thereby forming a single-strand break containing 3'-OH and 5'-dRP ends. In addition, Apn2 has 3'-phosphodiesterase activity (removing 3'-blocking groups) and 3' → 5' exonuclease activity (both much stronger than its AP endonuclease activity). Nonetheless, the role of the 3'-5'-exonuclease activity of Apn2 remains unclear and presumably is involved in the repair of damage containing single-strand breaks. In this work, by separating reaction products in a polyacrylamide gel and by a stopped-flow assay, we performed a kinetic analysis of the interaction of Apn2 with various model DNA substrates containing a 5' overhang. The results allowed us to propose a mechanism for the cleaving off of nucleotides and to determine the rate of the catalytic stage of the process. It was found that dissociation of a reaction product from the enzyme active site is not a rate-limiting step in the enzymatic reaction. We determined an influence of the nature of the 3'-terminal nucleotide that can be cleaved off on the course of the enzymatic reaction. Finally, it was found that the efficiency of the enzymatic reaction is context-specific.
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Comparative Analysis of Exo- and Endonuclease Activities of APE1-like Enzymes. Int J Mol Sci 2022; 23:ijms23052869. [PMID: 35270011 PMCID: PMC8911113 DOI: 10.3390/ijms23052869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 12/05/2022] Open
Abstract
Apurinic/apyrimidinic (AP)-endonucleases are multifunctional enzymes that are required for cell viability. AP-endonucleases incise DNA 5′ to an AP-site; can recognize and process some damaged nucleosides; and possess 3′-phosphodiesterase, 3′-phosphatase, and endoribonuclease activities. To elucidate the mechanism of substrate cleavage in detail, we analyzed the effect of mono- and divalent metal ions on the exo- and endonuclease activities of four homologous APE1-like endonucleases (from an insect (Rrp1), amphibian (xAPE1), fish (zAPE1), and from humans (hAPE1)). It was found that the enzymes had similar patterns of dependence on metal ions’ concentrations in terms of AP-endonuclease activity, suggesting that the main biological function (AP-site cleavage) was highly conserved among evolutionarily distant species. The efficiency of the 3′-5′ exonuclease activity was the highest in hAPE1 among these enzymes. In contrast, the endoribonuclease activity of the enzymes could be ranked as hAPE1 ≈ zAPE1 ≤ xAPE1 ≤ Rrp1. Taken together, the results revealed that the tested enzymes differed significantly in their capacity for substrate cleavage, even though the most important catalytic and substrate-binding amino acid residues were conserved. It can be concluded that substrate specificity and cleavage efficiency were controlled by factors external to the catalytic site, e.g., the N-terminal domain of these enzymes.
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Hindi NN, Elsakrmy N, Ramotar D. The base excision repair process: comparison between higher and lower eukaryotes. Cell Mol Life Sci 2021; 78:7943-7965. [PMID: 34734296 PMCID: PMC11071731 DOI: 10.1007/s00018-021-03990-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 09/08/2021] [Accepted: 10/14/2021] [Indexed: 01/01/2023]
Abstract
The base excision repair (BER) pathway is essential for maintaining the stability of DNA in all organisms and defects in this process are associated with life-threatening diseases. It is involved in removing specific types of DNA lesions that are induced by both exogenous and endogenous genotoxic substances. BER is a multi-step mechanism that is often initiated by the removal of a damaged base leading to a genotoxic intermediate that is further processed before the reinsertion of the correct nucleotide and the restoration of the genome to a stable structure. Studies in human and yeast cells, as well as fruit fly and nematode worms, have played important roles in identifying the components of this conserved DNA repair pathway that maintains the integrity of the eukaryotic genome. This review will focus on the components of base excision repair, namely, the DNA glycosylases, the apurinic/apyrimidinic endonucleases, the DNA polymerase, and the ligases, as well as other protein cofactors. Functional insights into these conserved proteins will be provided from humans, Saccharomyces cerevisiae, Drosophila melanogaster, and Caenorhabditis elegans, and the implications of genetic polymorphisms and knockouts of the corresponding genes.
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Affiliation(s)
- Nagham Nafiz Hindi
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar
| | - Noha Elsakrmy
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar
| | - Dindial Ramotar
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar.
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Malfatti MC, Antoniali G, Codrich M, Tell G. Coping with RNA damage with a focus on APE1, a BER enzyme at the crossroad between DNA damage repair and RNA processing/decay. DNA Repair (Amst) 2021; 104:103133. [PMID: 34049077 DOI: 10.1016/j.dnarep.2021.103133] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/06/2021] [Accepted: 05/09/2021] [Indexed: 12/17/2022]
Abstract
Interest in RNA damage as a novel threat associated with several human pathologies is rapidly increasing. Knowledge on damaged RNA recognition, repair, processing and decay is still scanty. Interestingly, in the last few years, more and more evidence put a bridge between DNA damage repair enzymes and the RNA world. The Apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1) was firstly identified as a crucial enzyme of the base excision repair (BER) pathway preserving genome stability toward non-distorting DNA lesion-induced damages. Later, an unsuspected role of APE1 in controlling gene expression was discovered and its pivotal involvement in several human pathologies, ranging from tumor progression to neurodegenerative diseases, has emerged. Recent novel findings indicate a role of APE1 in RNA metabolism, particularly in processing activities of damaged (abasic and oxidized) RNA and in the regulation of oncogenic microRNAs (miRNAs). Even though the role of miRNAs in human pathologies is well-known, the mechanisms underlying their quality control are still totally unexplored. A detailed knowledge of damaged RNA decay processes in human cells is crucial in order to understand the molecular processes involved in multiple pathologies. This cutting-edge perspective article will highlight these emerging aspects of damaged RNA processing and decay, focusing the attention on the involvement of APE1 in RNA world.
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Affiliation(s)
- Matilde Clarissa Malfatti
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
| | - Giulia Antoniali
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
| | - Marta Codrich
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
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Kuznetsova AA, Gavrilova AA, Novopashina DS, Fedorova OS, Kuznetsov NA. Mutational and Kinetic Analysis of APE1 Endoribonuclease Activity. Mol Biol 2021; 55:211-224. [PMID: 33948042 PMCID: PMC8083922 DOI: 10.1134/s0026893321020102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/09/2020] [Accepted: 11/09/2020] [Indexed: 12/20/2022]
Abstract
Human apurinic/apyrimidinic endonuclease 1 (APE1) participates in the DNA repair system. It is believed that the main biological function of APE1 is Mg2+-dependent hydrolysis of AP-sites in DNA. On the base of structural data, kinetic studies, and mutation analysis, the key stages of APE1 interaction with damaged DNA were established. It has been shown recently that APE1 can act as an endoribonuclease that catalyzes mRNA hydrolysis at certain pyrimidine–purine sites and thus controls the level of certain transcripts. In addition, the presence of Mg2+ ions was shown to be not required for the endoribonuclease activity of APE1, in contrast to the AP-endonuclease activity. This indicates differences in mechanisms of APE1 catalysis on RNA and DNA substrates, but the reasons for these differences remain unclear. Here, the analysis of endoribonuclease hydrolysis of model RNA substrates with wild type APE1 enzyme and its mutant forms Y171F, R177F, R181A, D210N, N212A, T268D, M270A, and D308A, was performed. It was shown that mutation of Asn212, Asp210, and Tyr171 residues leads to the decrease of AP-endonuclease activity while endoribonuclease activity is retained. Also, T268D and M270A APE1 mutants lose specificity to pyrimidine–purine sequences. R177F and R181A did not show a significant decrease in enzyme activity, whereas D308A demonstrated a decrease of endoribonuclease activity.
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Affiliation(s)
- A A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - A A Gavrilova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia.,Novosibirsk National Research State University, 630090 Novosibirsk, Russia
| | - D S Novopashina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - O S Fedorova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - N A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
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Davletgildeeva AT, Ishchenko AA, Saparbaev M, Fedorova OS, Kuznetsov NA. The Enigma of Substrate Recognition and Catalytic Efficiency of APE1-Like Enzymes. Front Cell Dev Biol 2021; 9:617161. [PMID: 33842455 PMCID: PMC8033172 DOI: 10.3389/fcell.2021.617161] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 02/22/2021] [Indexed: 11/13/2022] Open
Abstract
Despite significant achievements in the elucidation of the nature of protein-DNA contacts that control the specificity of nucleotide incision repair (NIR) by apurinic/apyrimidinic (AP) endonucleases, the question on how a given nucleotide is accommodated by the active site of the enzyme remains unanswered. Therefore, the main purpose of our study was to compare kinetics of conformational changes of three homologous APE1-like endonucleases (insect Drosophila melanogaster Rrp1, amphibian Xenopus laevis xAPE1, and fish Danio rerio zAPE1) during their interaction with various damaged DNA substrates, i.e., DNA containing an F-site (an uncleavable by DNA-glycosylases analog of an AP-site), 1,N6-ethenoadenosine (εA), 5,6-dihydrouridine (DHU), uridine (U), or the α-anomer of adenosine (αA). Pre-steady-state analysis of fluorescence time courses obtained for the interaction of the APE1-like enzymes with DNA substrates containing various lesions allowed us to outline a model of substrate recognition by this class of enzymes. It was found that the differences in rates of DNA substrates’ binding do not lead to significant differences in the cleavage efficiency of DNA containing a damaged base. The results suggest that the formation of enzyme–substrate complexes is not the key factor that limits enzyme turnover; the mechanisms of damage recognition and cleavage efficacy are related to fine conformational tuning inside the active site.
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Affiliation(s)
- Anastasiia T Davletgildeeva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Alexander A Ishchenko
- Group "Mechanisms of DNA Repair and Carcinogenesis", Equipe Labellisée LIGUE 2016, CNRS UMR 9019, Université Paris-Saclay, Villejuif, France
| | - Murat Saparbaev
- Group "Mechanisms of DNA Repair and Carcinogenesis", Equipe Labellisée LIGUE 2016, CNRS UMR 9019, Université Paris-Saclay, Villejuif, France
| | - Olga S Fedorova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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Davletgildeeva AT, Kuznetsova AA, Fedorova OS, Kuznetsov NA. Activity of Human Apurinic/Apyrimidinic Endonuclease APE1 Toward Damaged DNA and Native RNA With Non-canonical Structures. Front Cell Dev Biol 2020; 8:590848. [PMID: 33195255 PMCID: PMC7662432 DOI: 10.3389/fcell.2020.590848] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/30/2020] [Indexed: 01/02/2023] Open
Abstract
The primary role of apurinic/apyrimidinic (AP) endonuclease APE1 in human cells is the cleavage of the sugar phosphate backbone 5' to an AP site in DNA to produce a single-strand break with a 5'-deoxyribose phosphate and 3'-hydroxyl end groups. APE1 can also recognize and incise some damaged or modified nucleotides and possesses some minor activities: 3'-5' exonuclease, 3'-phosphodiesterase, 3'-phosphatase, and RNase H. A molecular explanation for the discrimination of structurally different substrates by the single active site of the enzyme remains elusive. Here, we report a mechanism of target nucleotide recognition by APE1 as revealed by the results of an analysis of the APE1 process involving damaged DNA and native RNA substrates with non-canonical structures. The mechanism responsible for substrate specificity proved to be directly related to the ability of a target nucleotide to get into the active site of APE1 in response to an enzyme-induced DNA distortion.
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Affiliation(s)
- Anastasia T Davletgildeeva
- Institute of Chemical Biology and Fundamental Medicine of the SB RAS, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Alexandra A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine of the SB RAS, Novosibirsk, Russia
| | - Olga S Fedorova
- Institute of Chemical Biology and Fundamental Medicine of the SB RAS, Novosibirsk, Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine of the SB RAS, Novosibirsk, Russia
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Kuznetsova AA, Akhmetgalieva AA, Ulyanova VV, Ilinskaya ON, Fedorova OS, Kuznetsov NA. Efficiency of RNA Hydrolysis by Binase from Bacillus pumilus: The Impact of Substrate Structure, Metal Ions, and Low Molecular Weight Nucleotide Compounds. Mol Biol 2020. [DOI: 10.1134/s0026893320050064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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Bulygin AA, Kuznetsova AA, Vorobjev YN, Fedorova OS, A. Kuznetsov N. The Role of Active-Site Plasticity in Damaged-Nucleotide Recognition by Human Apurinic/Apyrimidinic Endonuclease APE1. Molecules 2020; 25:molecules25173940. [PMID: 32872297 PMCID: PMC7504742 DOI: 10.3390/molecules25173940] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 12/19/2022] Open
Abstract
Human apurinic/apyrimidinic (AP) endonuclease APE1 hydrolyzes phosphodiester bonds on the 5′ side of an AP-site, and some damaged nucleotides such as 1,N6-ethenoadenosine (εA), α-adenosine (αA), and 5,6-dihydrouridine (DHU). To investigate the mechanism behind the broad substrate specificity of APE1, we analyzed pre-steady-state kinetics of conformational changes in DNA and the enzyme during DNA binding and damage recognition. Molecular dynamics simulations of APE1 complexes with one of damaged DNA duplexes containing εA, αA, DHU, or an F-site (a stable analog of an AP-site) revealed the involvement of residues Asn229, Thr233, and Glu236 in the mechanism of DNA lesion recognition. The results suggested that processing of an AP-site proceeds faster in comparison with nucleotide incision repair substrates because eversion of a small abasic site and its insertion into the active site do not include any unfavorable interactions, whereas the insertion of any target nucleotide containing a damaged base into the APE1 active site is sterically hindered. Destabilization of the α-helix containing Thr233 and Glu236 via a loss of the interaction between these residues increased the plasticity of the damaged-nucleotide binding pocket and the ability to accommodate structurally different damaged nucleotides. Nonetheless, the optimal location of εA or αA in the binding pocket does not correspond to the optimal conformation of catalytic amino acid residues, thereby significantly decreasing the cleavage efficacy for these substrates.
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Affiliation(s)
- Anatoly A. Bulygin
- Institute of Chemical Biology and Fundamental Medicine, Lavrentyev Ave. 8, 630090 Novosibirsk, Russia; (A.A.B.); (A.A.K.); (Y.N.V.)
- Department of Natural Sciences, Novosibirsk State University, Pirogova St. 2, 630090 Novosibirsk, Russia
| | - Alexandra A. Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine, Lavrentyev Ave. 8, 630090 Novosibirsk, Russia; (A.A.B.); (A.A.K.); (Y.N.V.)
| | - Yuri N. Vorobjev
- Institute of Chemical Biology and Fundamental Medicine, Lavrentyev Ave. 8, 630090 Novosibirsk, Russia; (A.A.B.); (A.A.K.); (Y.N.V.)
| | - Olga S. Fedorova
- Institute of Chemical Biology and Fundamental Medicine, Lavrentyev Ave. 8, 630090 Novosibirsk, Russia; (A.A.B.); (A.A.K.); (Y.N.V.)
- Department of Natural Sciences, Novosibirsk State University, Pirogova St. 2, 630090 Novosibirsk, Russia
- Correspondence: (O.S.F.); (N.A.K.)
| | - Nikita A. Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Lavrentyev Ave. 8, 630090 Novosibirsk, Russia; (A.A.B.); (A.A.K.); (Y.N.V.)
- Department of Natural Sciences, Novosibirsk State University, Pirogova St. 2, 630090 Novosibirsk, Russia
- Correspondence: (O.S.F.); (N.A.K.)
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