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Gouveia AG, Salgueiro BA, Ranmar DO, Antunes WDT, Kirchweger P, Golani O, Wolf SG, Elbaum M, Matias PM, Romão CV. Unraveling the multifaceted resilience of arsenic resistant bacterium Deinococcus indicus. Front Microbiol 2023; 14:1240798. [PMID: 37692390 PMCID: PMC10483234 DOI: 10.3389/fmicb.2023.1240798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/09/2023] [Indexed: 09/12/2023] Open
Abstract
Arsenic (As) is a toxic heavy metal widely found in the environment that severely undermines the integrity of water resources. Bioremediation of toxic compounds is an appellative sustainable technology with a balanced cost-effective setup. To pave the way for the potential use of Deinococcus indicus, an arsenic resistant bacterium, as a platform for arsenic bioremediation, an extensive characterization of its resistance to cellular insults is paramount. A comparative analysis of D. indicus cells grown in two rich nutrient media conditions (M53 and TGY) revealed distinct resistance patterns when cells are subjected to stress via UV-C and methyl viologen (MV). Cells grown in M53 demonstrated higher resistance to both UV-C and MV. Moreover, cells grow to higher density upon exposure to 25 mM As(V) in M53 in comparison with TGY. This analysis is pivotal for the culture of microbial species in batch culture bioreactors for bioremediation purposes. We also demonstrate for the first time the presence of polyphosphate granules in D. indicus which are also found in a few Deinococcus species. To extend our analysis, we also characterized DiArsC2 (arsenate reductase) involved in arsenic detoxification and structurally determined different states, revealing the structural evidence for a catalytic cysteine triple redox system. These results contribute for our understanding into the D. indicus resistance mechanism against stress conditions.
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Affiliation(s)
- André G. Gouveia
- Instituto de Tecnologia Química e Biológica António Xavier (ITQB NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
| | - Bruno A. Salgueiro
- Instituto de Tecnologia Química e Biológica António Xavier (ITQB NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
| | - Dean O. Ranmar
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Wilson D. T. Antunes
- Instituto Universitário Militar, Centro de Investigação da Academia Militar (CINAMIL), Unidade Militar Laboratorial de Defesa Biológica e Química (UMLDBQ), Lisbon, Portugal
| | - Peter Kirchweger
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Ofra Golani
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Sharon G. Wolf
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Michael Elbaum
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Pedro M. Matias
- Instituto de Tecnologia Química e Biológica António Xavier (ITQB NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
- Instituto de Biologia Experimental e Tecnológica (iBET), Oeiras, Portugal
| | - Célia V. Romão
- Instituto de Tecnologia Química e Biológica António Xavier (ITQB NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
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2
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Schröder HC, Wang X, Neufurth M, Wang S, Müller WEG. Biomimetic Polyphosphate Materials: Toward Application in Regenerative Medicine. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2022; 61:83-130. [PMID: 35697938 DOI: 10.1007/978-3-031-01237-2_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In recent years, inorganic polyphosphate (polyP) has attracted increasing attention as a biomedical polymer or biomaterial with a great potential for application in regenerative medicine, in particular in the fields of tissue engineering and repair. The interest in polyP is based on two properties of this physiological polymer that make polyP stand out from other polymers: polyP has morphogenetic activity by inducing cell differentiation through specific gene expression, and it functions as an energy store and donor of metabolic energy, especially in the extracellular matrix or in the extracellular space. No other biopolymer applicable in tissue regeneration/repair is known that is endowed with this combination of properties. In addition, polyP can be fabricated both in the form of a biologically active coacervate and as biomimetic amorphous polyP nano/microparticles, which are stable and are activated by transformation into the coacervate phase after contact with protein/body fluids. PolyP can be used in the form of various metal salts and in combination with various hydrogel-forming polymers, whereby (even printable) hybrid materials with defined porosities and mechanical and biological properties can be produced, which can even be loaded with cells for 3D cell printing or with drugs and support the growth and differentiation of (stem) cells as well as cell migration/microvascularization. Potential applications in therapy of bone, cartilage and eye disorders/injuries and wound healing are summarized and possible mechanisms are discussed.
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Affiliation(s)
- Heinz C Schröder
- ERC Advanced Investigator Group, Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Xiaohong Wang
- ERC Advanced Investigator Group, Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Meik Neufurth
- ERC Advanced Investigator Group, Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Shunfeng Wang
- ERC Advanced Investigator Group, Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Werner E G Müller
- ERC Advanced Investigator Group, Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany.
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3
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Housh K, Jha JS, Yang Z, Haldar T, Johnson KM, Yin J, Wang Y, Gates KS. Formation and Repair of an Interstrand DNA Cross-Link Arising from a Common Endogenous Lesion. J Am Chem Soc 2021; 143:15344-15357. [PMID: 34516735 DOI: 10.1021/jacs.1c06926] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Interstrand DNA cross-links (ICLs) are cytotoxic because they block the strand separation required for read-out and replication of the genetic information in duplex DNA. The unavoidable formation of ICLs in cellular DNA may contribute to aging, neurodegeneration, and cancer. Here, we describe the formation and properties of a structurally complex ICL derived from an apurinic/apyrimidinic (AP) site, which is one of the most common endogenous lesions in cellular DNA. The results characterize a cross-link arising from aza-Michael addition of the N2-amino group of a guanine residue to the electrophilic sugar remnant generated by spermine-mediated strand cleavage at an AP site in duplex DNA. An α,β-unsaturated iminium ion is the critical intermediate involved in ICL formation. Studies employing the bacteriophage φ29 polymerase provided evidence that this ICL can block critical DNA transactions that require strand separation. The results of biochemical studies suggest that this complex strand break/ICL might be repaired by a simple mechanism in which the 3'-exonuclease action of the enzyme apurinic/apyrimidinic endonuclease (APE1) unhooks the cross-link to initiate repair via the single-strand break repair pathway.
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Affiliation(s)
- Kurt Housh
- University of Missouri Department of Chemistry 125 Chemistry Building Columbia, Missouri 65211, United States
| | - Jay S Jha
- University of Missouri Department of Chemistry 125 Chemistry Building Columbia, Missouri 65211, United States
| | - Zhiyu Yang
- University of Missouri Department of Chemistry 125 Chemistry Building Columbia, Missouri 65211, United States
| | - Tuhin Haldar
- University of Missouri Department of Chemistry 125 Chemistry Building Columbia, Missouri 65211, United States
| | - Kevin M Johnson
- University of Missouri Department of Chemistry 125 Chemistry Building Columbia, Missouri 65211, United States
| | - Jiekai Yin
- Department of Chemistry University of California-Riverside Riverside, California 92521-0403, United States
| | - Yinsheng Wang
- Department of Chemistry University of California-Riverside Riverside, California 92521-0403, United States
| | - Kent S Gates
- University of Missouri Department of Chemistry 125 Chemistry Building Columbia, Missouri 65211, United States.,University of Missouri Department of Biochemistry 125 Chemistry Building Columbia, Missouri 65211, United States
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4
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Housh K, Jha JS, Haldar T, Amin SBM, Islam T, Wallace A, Gomina A, Guo X, Nel C, Wyatt JW, Gates KS. Formation and repair of unavoidable, endogenous interstrand cross-links in cellular DNA. DNA Repair (Amst) 2020; 98:103029. [PMID: 33385969 DOI: 10.1016/j.dnarep.2020.103029] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 02/08/2023]
Abstract
Genome integrity is essential for life and, as a result, DNA repair systems evolved to remove unavoidable DNA lesions from cellular DNA. Many forms of life possess the capacity to remove interstrand DNA cross-links (ICLs) from their genome but the identity of the naturally-occurring, endogenous substrates that drove the evolution and retention of these DNA repair systems across a wide range of life forms remains uncertain. In this review, we describe more than a dozen chemical processes by which endogenous ICLs plausibly can be introduced into cellular DNA. The majority involve DNA degradation processes that introduce aldehyde residues into the double helix or reactions of DNA with endogenous low molecular weight aldehyde metabolites. A smaller number of the cross-linking processes involve reactions of DNA radicals generated by oxidation.
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Affiliation(s)
- Kurt Housh
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Jay S Jha
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Tuhin Haldar
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Saosan Binth Md Amin
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Tanhaul Islam
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Amanda Wallace
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Anuoluwapo Gomina
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Xu Guo
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Christopher Nel
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Jesse W Wyatt
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Kent S Gates
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States; University of Missouri, Department of Biochemistry, Columbia, MO 65211, United States.
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5
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Singh A, Giri K. Effect of arsenate substitution on phosphate repository of cell: a computational study. ROYAL SOCIETY OPEN SCIENCE 2018; 5:181565. [PMID: 30564428 PMCID: PMC6281905 DOI: 10.1098/rsos.181565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 10/16/2018] [Indexed: 06/09/2023]
Abstract
The structural analogy with phosphate derives arsenate into various metabolic processes associated with phosphate inside the organisms. But it is difficult to evaluate the effect of arsenate substitution on the stability of individual biological phosphate species, which span from a simpler monoester form like pyrophosphate to a more complex phosphodiester variant like DNA. In this study, we have classified the physiological phosphate esters into three different classes on the basis of their structural differences. This classification has helped us to present a concise theoretical study on the kinetic stability of phosphate analogue species of arsenate against hydrolysis. All the calculations have been carried out using QM/MM methods of our Own N-layer Integrated molecular Orbital molecular Mechanics (ONIOM). For quantum mechanical region, we have used M06-2X density functional with 6-31+G(2d,2p) basis set and for molecular mechanics we have used the AMBER force field. The calculated rate constants for hydrolysis show that none of the phosphate analogue species of arsenate has a reasonable stability against hydrolysis.
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Affiliation(s)
- Amit Singh
- Department of Computational Sciences, Central University of Punjab, Bathinda-151001, India
| | - Kousik Giri
- Department of Computational Sciences, Central University of Punjab, Bathinda-151001, India
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6
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Pasek MA. The Origin of the Ionized Linker: Geochemical Predestination for Phosphate? ACTA ACUST UNITED AC 2018. [DOI: 10.1007/978-3-319-93584-3_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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7
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Abstract
The emergence of functional cooperation between the three main classes of biomolecules - nucleic acids, peptides and lipids - defines life at the molecular level. However, how such mutually interdependent molecular systems emerged from prebiotic chemistry remains a mystery. A key hypothesis, formulated by Crick, Orgel and Woese over 40 year ago, posits that early life must have been simpler. Specifically, it proposed that an early primordial biology lacked proteins and DNA but instead relied on RNA as the key biopolymer responsible not just for genetic information storage and propagation, but also for catalysis, i.e. metabolism. Indeed, there is compelling evidence for such an 'RNA world', notably in the structure of the ribosome as a likely molecular fossil from that time. Nevertheless, one might justifiably ask whether RNA alone would be up to the task. From a purely chemical perspective, RNA is a molecule of rather uniform composition with all four bases comprising organic heterocycles of similar size and comparable polarity and pK a values. Thus, RNA molecules cover a much narrower range of steric, electronic and physicochemical properties than, e.g. the 20 amino acid side-chains of proteins. Herein we will examine the functional potential of RNA (and other nucleic acids) with respect to self-replication, catalysis and assembly into simple protocellular entities.
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8
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Pathak AK, Bandyopadhyay T. Solvation of arsenate anion: combined quantum mechanics and molecular dynamics based investigation. Mol Phys 2016. [DOI: 10.1080/00268976.2016.1177219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Arup Kumar Pathak
- Theoretical Chemistry Section, Bhabha Atomic Research Centre, Mumbai, India
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9
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Jogalekar AS. Social Media, Peer Review, and Responsible Conduct of Research (RCR) in Chemistry: Trends, Pitfalls, and Promises. Account Res 2015; 22:402-30. [PMID: 26155733 PMCID: PMC4714242 DOI: 10.1080/08989621.2015.1047705] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Over the last two decades, various themes inherent in the responsible conduct of research (RCR) in chemistry have been brought to light through prominent cases of research misconduct. This article will describe a few of these cases especially through the lens of social media such as blogs and Twitter. A case will be made that these wholly novel modalities of online discussion are now complementing, and in some cases even circumventing some of the limitations of traditional peer review in chemistry. We present in detail our evaluation of three recent cases of RCR along with several other social media illustrations. These cases have been selected to be representative and showcase several of the most prominent issues at the intersection of traditional and social-media based peer review. In each case, basic details are presented along with a brief discussion of the underlying issues-readers interested in deeper analysis of each subject are referred to a collection of relevant articles and websites. This perspective focuses on the most important RCR issues that have arisen in the past decade, a time which we believe coincides with the serious participation of the scientific community in general, and the chemistry community in particular, in social media-based, citizen-enabled peer-review. A discussion of important trends in RCR in the age of social media, outstanding developments in this area, and questions of enduring interest for the near future concludes the article.
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Affiliation(s)
- Ashutosh S. Jogalekar
- Address correspondence to Ashutosh S. Jogalekar, 284 Harvard Street, Apartment 42, Cambridge, MA02139, USA. E-mail:
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10
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Huertas MJ, López-Maury L, Giner-Lamia J, Sánchez-Riego AM, Florencio FJ. Metals in cyanobacteria: analysis of the copper, nickel, cobalt and arsenic homeostasis mechanisms. Life (Basel) 2014; 4:865-86. [PMID: 25501581 PMCID: PMC4284471 DOI: 10.3390/life4040865] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 11/27/2014] [Accepted: 12/04/2014] [Indexed: 11/16/2022] Open
Abstract
Traces of metal are required for fundamental biochemical processes, such as photosynthesis and respiration. Cyanobacteria metal homeostasis acquires an important role because the photosynthetic machinery imposes a high demand for metals, making them a limiting factor for cyanobacteria, especially in the open oceans. On the other hand, in the last two centuries, the metal concentrations in marine environments and lake sediments have increased as a result of several industrial activities. In all cases, cells have to tightly regulate uptake to maintain their intracellular concentrations below toxic levels. Mechanisms to obtain metal under limiting conditions and to protect cells from an excess of metals are present in cyanobacteria. Understanding metal homeostasis in cyanobacteria and the proteins involved will help to evaluate the use of these microorganisms in metal bioremediation. Furthermore, it will also help to understand how metal availability impacts primary production in the oceans. In this review, we will focus on copper, nickel, cobalt and arsenic (a toxic metalloid) metabolism, which has been mainly analyzed in model cyanobacterium Synechocystis sp. PCC 6803.
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Affiliation(s)
- María José Huertas
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
| | - Luis López-Maury
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
| | - Joaquín Giner-Lamia
- Systems Biology and Bioinformatics Laboratory, IBB-CBME, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
| | - Ana María Sánchez-Riego
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
| | - Francisco Javier Florencio
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
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11
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Genomic responses to arsenic in the cyanobacterium Synechocystis sp. PCC 6803. PLoS One 2014; 9:e96826. [PMID: 24797411 PMCID: PMC4010505 DOI: 10.1371/journal.pone.0096826] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 04/11/2014] [Indexed: 12/02/2022] Open
Abstract
Arsenic is a ubiquitous contaminant and a toxic metalloid which presents two main redox states in nature: arsenite [AsIII] and arsenate [AsV]. Arsenic resistance in Synechocystis sp. strain PCC 6803 is mediated by the arsBHC operon and two additional arsenate reductases encoded by the arsI1 and arsI2 genes. Here we describe the genome-wide responses to the presence of arsenate and arsenite in wild type and mutants in the arsenic resistance system. Both forms of arsenic produced similar responses in the wild type strain, including induction of several stress related genes and repression of energy generation processes. These responses were transient in the wild type strain but maintained in time in an arsB mutant strain, which lacks the arsenite transporter. In contrast, the responses observed in a strain lacking all arsenate reductases were somewhat different and included lower induction of genes involved in metal homeostasis and Fe-S cluster biogenesis, suggesting that these two processes are targeted by arsenite in the wild type strain. Finally, analysis of the arsR mutant strain revealed that ArsR seems to only control 5 genes in the genome. Furthermore, the arsR mutant strain exhibited hypersentivity to nickel, copper and cadmium and this phenotype was suppressed by mutation in arsB but not in arsC gene suggesting that overexpression of arsB is detrimental in the presence of these metals in the media.
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12
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Affiliation(s)
- Shengwen Shen
- Department
of Laboratory Medicine
and Pathology, 10-102 Clinical Sciences Building, University
of Alberta, Edmonton, Alberta, Canada, T6G 2G3
| | - Xing-Fang Li
- Department
of Laboratory Medicine
and Pathology, 10-102 Clinical Sciences Building, University
of Alberta, Edmonton, Alberta, Canada, T6G 2G3
| | - William R. Cullen
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver,
British Columbia, Canada, V6T 1Z1
| | - Michael Weinfeld
- Department of Oncology, Cross
Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada, T6G 1Z2
| | - X. Chris Le
- Department
of Laboratory Medicine
and Pathology, 10-102 Clinical Sciences Building, University
of Alberta, Edmonton, Alberta, Canada, T6G 2G3
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13
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Jissy AK, Datta A. Can Arsenates Replace Phosphates in Natural Biochemical Processes? A Computational Study. J Phys Chem B 2013; 117:8340-6. [PMID: 23789648 DOI: 10.1021/jp402917q] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- A. K. Jissy
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, CET Campus, Thiruvananthapuram-695016, Kerala, India
| | - Ayan Datta
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, CET Campus, Thiruvananthapuram-695016, Kerala, India
- Department of Spectroscopy, Indian Association for the Cultivation of Science,
Jadavpur-700032, West Bengal, India
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14
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Sudhani HPK, García-Murria MJ, Moreno J. Reversible inhibition of CO2 fixation by ribulose 1,5-bisphosphate carboxylase/oxygenase through the synergic effect of arsenite and a monothiol. PLANT, CELL & ENVIRONMENT 2013; 36:1160-1170. [PMID: 23216059 DOI: 10.1111/pce.12050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 11/27/2012] [Accepted: 11/28/2012] [Indexed: 06/01/2023]
Abstract
The activity of the photosynthetic carbon-fixing enzyme, ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), is partially inhibited by arsenite in the millimolar concentration range. However, micromolar arsenite can fully inhibit Rubisco in the presence of a potentiating monothiol such as cysteine, cysteamine, 2-mercaptoethanol or N-acetylcysteine, but not glutathione. Arsenite reacts specifically with the vicinal Cys172-Cys192 from the large subunit of Rubisco and with the monothiol to establish a ternary complex, which is suggested to be a trithioarsenical. The stability of the complex is strongly dependent on the nature of the monothiol. Enzyme activity is fully recovered through the disassembly of the complex after eliminating arsenite and/or the thiol from the medium. The synergic combination of arsenite and a monothiol acts also in vivo stopping carbon dioxide fixation in illuminated cultures of Chlamydomonas reinhardtii. Again, this effect may be reverted by washing the cells. However, in vivo inhibition does not result from the blocking of Rubisco since mutant strains carrying Rubiscos with Cys172 and/or Cys192 substitutions (which are insensitive to arsenite in vitro) are also arrested. This suggests the existence of a specific sensor controlling carbon fixation that is even more sensitive than Rubisco to the arsenite-thiol synergism.
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Affiliation(s)
- Hemanth P K Sudhani
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Valencia, Burjassot, E-46100, Spain
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15
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A molecular dynamics study of the structural and dynamical properties of putative arsenic substituted lipid bilayers. Int J Mol Sci 2013; 14:7702-15. [PMID: 23571494 PMCID: PMC3645711 DOI: 10.3390/ijms14047702] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 03/23/2013] [Accepted: 03/29/2013] [Indexed: 11/17/2022] Open
Abstract
Cell membranes are composed mainly of phospholipids which are in turn, composed of five major chemical elements: carbon, hydrogen, nitrogen, oxygen, and phosphorus. Recent studies have suggested the possibility of sustaining life if the phosphorus is substituted by arsenic. Although this issue is still controversial, it is of interest to investigate the properties of arsenated-lipid bilayers to evaluate this possibility. In this study, we simulated arsenated-lipid, 1-palmitoyl-2-oleoyl-sn-glycero-3-arsenocholine (POAC), lipid bilayers using all-atom molecular dynamics to understand basic structural and dynamical properties, in particular, the differences from analogous 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, (POPC) lipid bilayers. Our simulations showed that POAC lipid bilayers have distinct structural and dynamical properties from those of native POPC lipid bilayers. Relative to POPC lipid bilayers, POAC lipid bilayers have a more compact structure with smaller lateral areas and greater order. The compact structure of POAC lipid bilayers is due to the fact that more inter-lipid salt bridges are formed with arsenate-choline compared to the phosphate-choline of POPC lipid bilayers. These inter-lipid salt bridges bind POAC lipids together and also slow down the head group rotation and lateral diffusion of POAC lipids. Thus, it would be anticipated that POAC and POPC lipid bilayers would have different biological implications.
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16
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Kruger MC, Bertin PN, Heipieper HJ, Arsène-Ploetze F. Bacterial metabolism of environmental arsenic--mechanisms and biotechnological applications. Appl Microbiol Biotechnol 2013; 97:3827-41. [PMID: 23546422 DOI: 10.1007/s00253-013-4838-5] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 03/05/2013] [Accepted: 03/06/2013] [Indexed: 01/13/2023]
Abstract
Arsenic causes threats for environmental and human health in numerous places around the world mainly due to its carcinogenic potential at low doses. Removing arsenic from contaminated sites is hampered by the occurrence of several oxidation states with different physicochemical properties. The actual state of arsenic strongly depends on its environment whereby microorganisms play important roles in its geochemical cycle. Due to its toxicity, nearly all organisms possess metabolic mechanisms to resist its hazardous effects, mainly by active extrusion, but also by extracellular precipitation, chelation, and intracellular sequestration. Some microbes are even able to actively use various arsenic compounds in their metabolism, either as an electron donor or as a terminal electron acceptor for anaerobic respiration. Some microorganisms can also methylate inorganic arsenic, probably as a resistance mechanism, or demethylate organic arsenicals. Bioavailability of arsenic in water and sediments is strongly influenced by such microbial activities. Therefore, understanding microbial reactions to arsenic is of importance for the development of technologies for improved bioremediation of arsenic-contaminated waters and environments. This review gives an overview of the current knowledge on bacterial interactions with arsenic and on biotechnologies for its detoxification and removal.
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Affiliation(s)
- Martin C Kruger
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany
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18
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Abstract
Phosphoryl transfer plays key roles in signaling, energy transduction, protein synthesis, and maintaining the integrity of the genetic material. On the surface, it would appear to be a simple nucleophile displacement reaction. However, this simplicity is deceptive, as, even in aqueous solution, the low-lying d-orbitals on the phosphorus atom allow for eight distinct mechanistic possibilities, before even introducing the complexities of the enzyme catalyzed reactions. To further complicate matters, while powerful, traditional experimental techniques such as the use of linear free-energy relationships (LFER) or measuring isotope effects cannot make unique distinctions between different potential mechanisms. A quarter of a century has passed since Westheimer wrote his seminal review, 'Why Nature Chose Phosphate' (Science 235 (1987), 1173), and a lot has changed in the field since then. The present review revisits this biologically crucial issue, exploring both relevant enzymatic systems as well as the corresponding chemistry in aqueous solution, and demonstrating that the only way key questions in this field are likely to be resolved is through careful theoretical studies (which of course should be able to reproduce all relevant experimental data). Finally, we demonstrate that the reason that nature really chose phosphate is due to interplay between two counteracting effects: on the one hand, phosphates are negatively charged and the resulting charge-charge repulsion with the attacking nucleophile contributes to the very high barrier for hydrolysis, making phosphate esters among the most inert compounds known. However, biology is not only about reducing the barrier to unfavorable chemical reactions. That is, the same charge-charge repulsion that makes phosphate ester hydrolysis so unfavorable also makes it possible to regulate, by exploiting the electrostatics. This means that phosphate ester hydrolysis can not only be turned on, but also be turned off, by fine tuning the electrostatic environment and the present review demonstrates numerous examples where this is the case. Without this capacity for regulation, it would be impossible to have for instance a signaling or metabolic cascade, where the action of each participant is determined by the fine-tuned activity of the previous piece in the production line. This makes phosphate esters the ideal compounds to facilitate life as we know it.
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Abstract
The advantageous chemical properties of the phosphate ester linkage were exploited early in evolution to generate the phosphate diester linkages that join neighbouring bases in RNA and DNA (Westheimer 1987 Science 235, 1173-1178). Following the fixation of the genetic code, another use for phosphate ester modification was found, namely reversible phosphorylation of the three hydroxyamino acids, serine, threonine and tyrosine, in proteins. During the course of evolution, phosphorylation emerged as one of the most prominent types of post-translational modification, because of its versatility and ready reversibility. Phosphoamino acids generated by protein phosphorylation act as new chemical entities that do not resemble any natural amino acid, and thereby provide a means of diversifying the chemical nature of protein surfaces. A protein-linked phosphate group can form hydrogen bonds or salt bridges either intra- or intermolecularly, creating stronger hydrogen bonds with arginine than either aspartate or glutamate. The unique size of the ionic shell and charge properties of covalently attached phosphate allow specific and inducible recognition of phosphoproteins by phosphospecific-binding domains in other proteins, thus promoting inducible protein-protein interaction. In this manner, phosphorylation serves as a switch that allows signal transduction networks to transmit signals in response to extracellular stimuli.
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Affiliation(s)
- Tony Hunter
- Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
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21
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Shinde RN, Das S, Acharya R, Rajurkar NS, Pandey AK. Iron-complexed adsorptive membrane for As(V) species in water. JOURNAL OF HAZARDOUS MATERIALS 2012; 233-234:131-139. [PMID: 22835769 DOI: 10.1016/j.jhazmat.2012.07.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Revised: 06/28/2012] [Accepted: 07/01/2012] [Indexed: 06/01/2023]
Abstract
Selective preconcentration of a target analyte in the solid phase is an effective route not only to enhance detection limit of the conventional analytical method but also for elimination of interfering matrix. An adsorptive membrane was developed for selective preconcentration and quantification of ultra-trace (ppb) amounts of As(V) present in a variety of aqueous samples. The precursor membrane was prepared by UV-initiator induced graft polymerization of sulphate and phosphate bearing monomers (1:1 mol proportion) in pores of the host microporous poly(propylene) membrane. Fe(3+) ions were loaded in the precursor membrane to make it selective for As(V) ions. The presence of phosphate functional groups prevent leaching of Fe(3+) ions from the membrane when it comes in contact with solution like seawater having high ionic strength. The optimized membrane was characterized in terms of its physical structure, chemical structure and experimental conditions affecting As(V) uptake in the membrane. The possibility of quantifying total preconcentration of As content was also explored by converting As(III) to As(V). To quantify As(V), the membrane samples were subjected to instrumental neutron activation analysis (INAA). The studies carried in the present work showed that quantification of inorganic arsenic species in natural water samples is easily possible in 2-3 ppb concentration range.
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Affiliation(s)
- Rakesh N Shinde
- Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India
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22
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Hunter T. Why nature chose phosphate to modify proteins. Philos Trans R Soc Lond B Biol Sci 2012. [PMID: 22889903 DOI: 10.1098/rstb.2012.0013.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The advantageous chemical properties of the phosphate ester linkage were exploited early in evolution to generate the phosphate diester linkages that join neighbouring bases in RNA and DNA (Westheimer 1987 Science 235, 1173-1178). Following the fixation of the genetic code, another use for phosphate ester modification was found, namely reversible phosphorylation of the three hydroxyamino acids, serine, threonine and tyrosine, in proteins. During the course of evolution, phosphorylation emerged as one of the most prominent types of post-translational modification, because of its versatility and ready reversibility. Phosphoamino acids generated by protein phosphorylation act as new chemical entities that do not resemble any natural amino acid, and thereby provide a means of diversifying the chemical nature of protein surfaces. A protein-linked phosphate group can form hydrogen bonds or salt bridges either intra- or intermolecularly, creating stronger hydrogen bonds with arginine than either aspartate or glutamate. The unique size of the ionic shell and charge properties of covalently attached phosphate allow specific and inducible recognition of phosphoproteins by phosphospecific-binding domains in other proteins, thus promoting inducible protein-protein interaction. In this manner, phosphorylation serves as a switch that allows signal transduction networks to transmit signals in response to extracellular stimuli.
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Affiliation(s)
- Tony Hunter
- Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
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23
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Abstract
Halomonas strain GFAJ-1 was reported in Science magazine to be a remarkable microbe for which there was "arsenate in macromolecules that normally contain phosphate, most notably nucleic acids." The draft genome of the bacterium was determined (NCBI accession numbers AHBC01000001 through AHBC01000103). It appears to be a typical gamma proteobacterium.
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Xu Y, Ma B, Nussinov R. Structural and functional consequences of phosphate-arsenate substitutions in selected nucleotides: DNA, RNA, and ATP. J Phys Chem B 2012; 116:4801-11. [PMID: 22480264 PMCID: PMC3337691 DOI: 10.1021/jp300307u] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 04/04/2012] [Indexed: 12/23/2022]
Abstract
A recent finding of a bacterial strain (GFAJ-1) that can rely on arsenic instead of phosphorus raised the questions of if and how arsenate can replace phosphate in biomolecules that are essential to sustain cell life. Apart from questions related to chemical stability, there are those of the structural and functional consequences of phosphate-arsenate substitutions in vital nucleotides in GFAJ1-like cells. In this study we selected three types of molecules (ATP/ADP as energy source and replication regulation; DNA-protein complexes for DNA replication and transcription initiation; and a tRNA-protein complex and ribosome for protein synthesis) to computationally probe if arsenate nucleotides can retain the structural and functional features of phosphate nucleotides. Hydrolysis of adenosine triarsenate provides 2-3 kcal/mol less energy than ATP hydrolysis. Arsenate DNA/RNA interacts with proteins slightly less strongly than phosphate DNA/RNA, mainly due to the weaker electrostatic interactions of arsenate. We observed that the weaker arsenate RNA-protein interactions may hamper rRNA assembly into a functional ribosome. We further compared the experimental EXAFS spectra of the arsenic bacteria with theoretical EXAFS spectra for arsenate DNA and rRNA. Our results demonstrate that while it is possible that dried GFAJ-1 cells contain linear arsenate DNA, the arsenate 70S ribosome does not contribute to the main arsenate depository in the GFAJ-1 cell. Our study indicates that evolution has optimized the inter-relationship between proteins and DNA/RNA, which requires overall changes at the molecular and systems biology levels when replacing phosphate by arsenate.
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Affiliation(s)
- Yu Xu
- Institute of Chinese Minority
Traditional Medicine, Minzu University of China, Beijing 100081, People’s Republic of China
| | - Buyong Ma
- Basic Science Program, SAIC-Frederick,
Inc., Center for Cancer Research Nanobiology Program, NCI-Frederick, NIH, Frederick, Maryland 21702, United States
| | - Ruth Nussinov
- Institute of Chinese Minority
Traditional Medicine, Minzu University of China, Beijing 100081, People’s Republic of China
- Sackler Institute of Molecular
Medicine, Department of Human Genetics and Molecular Medicine, Sackler
School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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Couture RM, Sekowska A, Fang G, Danchin A. Linking selenium biogeochemistry to the sulfur-dependent biological detoxification of arsenic. Environ Microbiol 2012; 14:1612-23. [DOI: 10.1111/j.1462-2920.2012.02758.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Dani SU. The arsenic for phosphorus swap is accidental, rather than a facultative one, and the question whether arsenic is nonessential or toxic is quantitative, not a qualitative one. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:4889-4890. [PMID: 21719071 DOI: 10.1016/j.scitotenv.2011.05.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 05/08/2011] [Accepted: 05/18/2011] [Indexed: 05/31/2023]
Abstract
Arsenic shares many physicochemical properties with phosphorus, so that arsenic can be taken up inadvertently by cells through the pathways for phosphorus. As a phosphate analog, arsenate competes with phosphate and enters cells via phosphate transporters. In the cell, arsenate can be recognized as a substrate by enzymes that usually use phosphate as a substrate. The phosphate for arsenate swap results in wasteful 'futile cycles' in metabolic pathways, uncoupled oxidative phosphorylation and extreme DNA instability. The disrupting metabolic effects of arsenic have an evolutionary meaning, so that all living organisms-from chemoautotrophic organisms that grow by reducing or oxidizing arsenic to metazoan--carry highly conserved arsenic resistance genes. Arsenic resistance can result from different strategies including selective transport to maximize phosphate uptake and minimize entry of arsenate, active transport to export arsenate, arsenic storage in specialized compartments, enzyme selectivity toward phosphate, and increased efficiency of DNA repair systems. None of these strategies is infallible, though, and susceptibility to arsenic toxicity varies between taxa in many orders of magnitude. Even arsenic-hypertolerant organisms will stop to grow and will eventually die when exposed to arsenic over species-specific resistance limits. The arsenic for phosphorus swap is an accidental one, it does not warrant a conclusion in favor of the essentiality of arsenic to life as we know it.
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Affiliation(s)
- Sergio U Dani
- Department of Medicine I and Clinical Chemistry, University of Heidelberg, Germany.
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27
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Controversy over the report on a bacterium that feeds on arsenic. J Biosci 2011; 36:555-7. [PMID: 21857101 DOI: 10.1007/s12038-011-9076-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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28
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Akabayov B, Kulczyk AW, Akabayov SR, Theile C, McLaughlin LW, Beauchamp B, van Oijen AM, Richardson CC. Pyrovanadolysis, a pyrophosphorolysis-like reaction mediated by pyrovanadate, Mn2+, and DNA polymerase of bacteriophage T7. J Biol Chem 2011; 286:29146-29157. [PMID: 21697085 DOI: 10.1074/jbc.m111.250944] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
DNA polymerases catalyze the 3'-5'-pyrophosphorolysis of a DNA primer annealed to a DNA template in the presence of pyrophosphate (PP(i)). In this reversal of the polymerization reaction, deoxynucleotides in DNA are converted to deoxynucleoside 5'-triphosphates. Based on the charge, size, and geometry of the oxygen connecting the two phosphorus atoms of PP(i), a variety of compounds was examined for their ability to carry out a reaction similar to pyrophosphorolysis. We describe a manganese-mediated pyrophosphorolysis-like activity using pyrovanadate (VV) catalyzed by the DNA polymerase of bacteriophage T7. We designate this reaction pyrovanadolysis. X-ray absorption spectroscopy reveals a shorter Mn-V distance of the polymerase-VV complex than the Mn-P distance of the polymerase-PP(i) complex. This structural arrangement at the active site accounts for the enzymatic activation by Mn-VV. We propose that the Mn(2+), larger than Mg(2+), fits the polymerase active site to mediate binding of VV into the active site of the polymerase. Our results may be the first documentation that vanadium can substitute for phosphorus in biological processes.
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Affiliation(s)
- Barak Akabayov
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
| | - Arkadiusz W Kulczyk
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
| | - Sabine R Akabayov
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
| | - Christopher Theile
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
| | - Larry W McLaughlin
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, and
| | - Benjamin Beauchamp
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
| | - Antoine M van Oijen
- Zernike Institute for Advanced Materials Centre for Synthetic Biology, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Charles C Richardson
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115,.
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Mládek A, Sponer J, Sumpter BG, Fuentes-Cabrera M, Sponer JE. Theoretical modeling on the kinetics of the arsenate-ester hydrolysis: implications to the stability of As-DNA. Phys Chem Chem Phys 2011; 13:10869-71. [PMID: 21562664 DOI: 10.1039/c1cp20423h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Quantum chemical calculations reveal that neither steric hindrance nor less polar solvent medium is able to reduce the otherwise high hydrolysis rate of arsenate-esters. These results question the stability of As-DNA not only in aqueous but also in non-aqueous environments.
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Affiliation(s)
- Arnošt Mládek
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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Denning EJ, MacKerell AD. Impact of arsenic/phosphorus substitution on the intrinsic conformational properties of the phosphodiester backbone of DNA investigated using ab initio quantum mechanical calculations. J Am Chem Soc 2011; 133:5770-2. [PMID: 21443192 PMCID: PMC3076535 DOI: 10.1021/ja201213b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Deoxyribonucleic acid (DNA) is composed of five major elements carbon, hydrogen, nitrogen, oxygen, and phosphorus. The substitution of any of these elements in DNA would be anticipated to have major biological implications. However, recent studies have suggested that the substitution of arsenic into DNA (As-DNA) in bacteria may be possible. To help evaluate this possibility, ab initio quantum mechanical calculations are used to show that arsenodiester and phosphodiester linkages have similar geometric and conformational properties. Based on these results, it is suggested that the As-DNA will have similar conformational properties to phosphorus-based DNA, including the maintenance of base stacking.
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Affiliation(s)
- Elizabeth J. Denning
- Department of Pharmaceutical Sciences, University of Maryland, 20 Penn Street, Baltimore, MD 21201
| | - Alexander D. MacKerell
- Department of Pharmaceutical Sciences, University of Maryland, 20 Penn Street, Baltimore, MD 21201
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31
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Soares J. We are still alone! ACS Chem Biol 2011; 6:117. [PMID: 21329377 DOI: 10.1021/cb200023y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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32
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Nielsen PE. Natural Arsenate DNA? ARTIFICIAL DNA, PNA & XNA 2011; 2:4-5. [PMID: 21686246 PMCID: PMC3116578 DOI: 10.4161/adna.2.1.15657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 03/30/2011] [Indexed: 05/30/2023]
Abstract
The recent paper by Wolfe-Simon et al.1 reporting a bacterial strain, which is able to grow in high concentrations of arsenate, apparently in the absence of phosphate, and claims that in this strain arsenate is substituting for phosphate, e.g. in nucleic acids (Figure 1), was highly profiled, attracted broad attention, and almost immediately resulted in heavy scientific criticism (see e.g. 2-7).
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Affiliation(s)
- Peter E Nielsen
- University of Copenhagen, Department of Cellular & Molecular Medicine, The Panum Institute; Copenhagen N, Denmark
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