1
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Ghosh R, Roy L, Mukherjee D, Sarker S, Mondal J, Pan N, Hasan MN, Ghosh S, Chattopadhyay A, Adhikary A, Bhattacharyya M, Mallick AK, Biswas R, Das R, Pal SK. Structurally Dynamic Monocyte-Liposome Hybrid Vesicles as an Anticancer Drug Delivery Vehicle: A Crucial Correlation of Microscopic Elasticity and Ultrafast Dynamics. J Phys Chem Lett 2024; 15:3078-3088. [PMID: 38467015 DOI: 10.1021/acs.jpclett.3c03192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
A biomimetic cell-based carrier system based on monocyte membranes and liposomes has been designed to create a hybrid "Monocyte-LP" which inherits the surface antigens of the monocytes along with the drug encapsulation property of the liposome. Förster resonance energy transfer (FRET) and polarization gated anisotropy measurements show the stiffness of the vesicles obtained from monocyte membranes (Mons), phosphatidylcholine membranes (LP), and Monocyte-LP to follow an increasing order of Mons > Monocyte-LP > LP. The dynamics of interface bound water molecules plays a key role in the elasticity of the vesicles, which in turn imparts higher delivery efficacy to the hybrid Monocyte-LP for a model anticancer drug doxorubicin than the other two vesicles, indicating a critical balance between flexibility and rigidity for an efficient cellular uptake. The present work provides insight on the influence of elasticity of delivery vehicles for enhanced drug delivery.
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Affiliation(s)
- Ria Ghosh
- Department of Biochemistry, University of Calcutta 35 Ballygunge Circular Road, Ballygunge, Kolkata 700019, India
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Lopamudra Roy
- Department of Applied Optics and Photonics, University of Calcutta, Block-JD, Sector-III, Saltlake, Kolkata 700106, India
| | - Dipanjan Mukherjee
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Sushmita Sarker
- Centre for Research in Nanoscience and Nanotechnology, University of Calcutta, Salt Lake, Kolkata 700106, India
| | - Jayanta Mondal
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Nivedita Pan
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Md Nur Hasan
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Subhajit Ghosh
- Department of Life Science & Biotechnology, Jadavpur University, 188, Raja Subodh Chandra Mallick Rd, Jadavpur, Kolkata, West Bengal 700032, India
| | - Arpita Chattopadhyay
- Department of Basic science and Humanities, Techno International New Town Block, DG 1/1, Action Area 1, New Town, Rajarhat, Kolkata 700156, India
| | - Arghya Adhikary
- Department of Life Science & Biotechnology, Jadavpur University, 188, Raja Subodh Chandra Mallick Rd, Jadavpur, Kolkata, West Bengal 700032, India
| | - Maitree Bhattacharyya
- Department of Biochemistry, University of Calcutta 35 Ballygunge Circular Road, Ballygunge, Kolkata 700019, India
| | - Asim Kumar Mallick
- Department of Paediatric Medicine, Nil RatanSircar Medical College & Hospital, 138, AJC Bose Road, Sealdah, Raja Bazar, Kolkata 700014, India
| | - Ranjit Biswas
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Ranjan Das
- Department of Chemistry, West Bengal State University, Barasat, Kolkata 700126, India
| | - Samir Kumar Pal
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata, West Bengal 700106, India
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2
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Marefat Khah A, Reinholdt P, Nuernberger P, Kongsted J, Hättig C. Relaxation Dynamics of the Triazene Compound Berenil in DNA-Minor-Groove Confinement after Photoexcitation. J Chem Theory Comput 2020; 16:5203-5211. [DOI: 10.1021/acs.jctc.0c00489] [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]
Affiliation(s)
| | - Peter Reinholdt
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense, Denmark
| | - Patrick Nuernberger
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, 93040 Regensburg, Germany
| | - Jacob Kongsted
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense, Denmark
| | - Christof Hättig
- Quantum Chemistry Group, Ruhr University of Bochum, D-44780 Bochum, Germany
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3
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Sardana D, Yadav K, Shweta H, Clovis NS, Alam P, Sen S. Origin of Slow Solvation Dynamics in DNA: DAPI in Minor Groove of Dickerson-Drew DNA. J Phys Chem B 2019; 123:10202-10216. [PMID: 31589442 DOI: 10.1021/acs.jpcb.9b09275] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The measurement and understanding of collective solvation dynamics in DNA have vital biological implications, as protein and ligand binding to DNA can be directly controlled by complex electrostatic interactions of anionic DNA and surrounding dipolar water, and ions. Time-resolved fluorescence Stokes shift (TRFSS) experiments revealed anomalously slow solvation dynamics in DNA much beyond 100 ps that follow either power-law or slow multiexponential decay over several nanoseconds. The origin of such dispersed dynamics remains difficult to understand. Here we compare results of TRFSS experiments to molecular dynamics (MD) simulations of well-known 4',6-diamidino-2-phenylindole (DAPI)/Dickerson-Drew DNA complex over five decades of time from 100 fs to 10 ns to understand the origin of such dispersed dynamics. We show that the solvation time-correlation function (TCF) calculated from 200 ns simulation trajectory (total 800 ns) captures most features of slow dynamics as measured in TRFSS experiments. Decomposition of TCF into individual components unravels that slow dynamics originating from dynamically coupled DNA-water motion, although contribution from coupled water-Na+ motion is non-negligible. The analysis of residence time of water molecules around the probe (DAPI) reveals broad distribution from ∼6 ps to ∼3.5 ns: Several (49 nos.) water molecules show residences time greater than 500 ps, of which at least 14 water molecules show residence times of more than 1 ns in the first solvation shell of DAPI. Most of these slow water molecules are found to occupy two hydration sites in the minor groove near DAPI binding site. The residence time of Na+, however, is found to vary within ∼17-120 ps. Remarkably, we find that freezing the DNA fluctuations in simulation eliminates slower dynamics beyond ∼100 ps, where water and Na+ dynamics become faster, although strong anticorrelation exists between them. These results indicate that primary origin of slow dynamics lies within the slow fluctuations of DNA parts that couple with nearby slow water and ions to control the dispersed collective solvation dynamics in DNA minor groove.
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Affiliation(s)
- Deepika Sardana
- Spectroscopy Laboratory, School of Physical Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Kavita Yadav
- Spectroscopy Laboratory, School of Physical Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Him Shweta
- Spectroscopy Laboratory, School of Physical Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Ndege Simisi Clovis
- Spectroscopy Laboratory, School of Physical Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Parvez Alam
- Spectroscopy Laboratory, School of Physical Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Sobhan Sen
- Spectroscopy Laboratory, School of Physical Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
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4
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Sheu SY, Liu YC, Zhou JK, Schlag EW, Yang DY. Surface Topography Effects of Globular Biomolecules on Hydration Water. J Phys Chem B 2019; 123:6917-6932. [PMID: 31282162 DOI: 10.1021/acs.jpcb.9b03734] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Hydration water serves as a microscopic manifestation of structural stability and functions of biomolecules. To develop bio-nanomaterials in applications, it is important to study how the surface topography and heterogeneity of biomolecules result in their diversity of the hydration dynamics and energetics. We here performed molecular dynamics simulations combined with the steered molecular dynamics and umbrella sampling to investigate the dynamics and escape process associated with the free energy change of water molecules close to a globular biomolecule, i.e., hemoglobin (Hb) and G-quadruplex DNA (GDNA). The residence time, power of long-time tail, and dipole relaxation time were found to display drastic changes within the averaged hydration shell of 3.0-5.0 Å. Compared with bulk water, in the inner hydration shell, the water dipole moment displays a slower relaxation process and is more oriented toward GDNA than toward Hb, forming a hedgehog-like structure when it surrounds GDNA. In particular, a spine water structure is observed in the GDNA narrow groove. The water isotope effect not only prolongs the dynamic time scales of libration motion in the inner hydration shell and the dipole relaxation processes in the bulk but also strengthens the DNA spine water structure. The potential of the mean force profile reflects the integrity of the hydration shell structure and enables us to obtain detailed insights into the structures formed by water, such as the caged H-bond network and the edge bridge structures; it also reveals that local hydration shell free energy (LHSFE) depends on H-bond rupture processes and ranges from 0.2 to 4.2 kcal/mol. Our results demonstrate that the surface topography of a biomolecule influences the integrity of the hydration shell structure and LHSFE. Our studies are able to identify various further applications in the areas of microfluid devices and nano-dewetting on bioinspired surfaces.
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Affiliation(s)
- Sheh-Yi Sheu
- Department of Life Sciences and Institute of Genome Sciences , National Yang-Ming University , Taipei 112 , Taiwan.,Institute of Biomedical Informatics , National Yang-Ming University , Taipei 112 , Taiwan
| | - Yu-Cheng Liu
- Institute of Biomedical Informatics , National Yang-Ming University , Taipei 112 , Taiwan
| | - Jia-Kai Zhou
- Department of Life Sciences and Institute of Genome Sciences , National Yang-Ming University , Taipei 112 , Taiwan
| | - Edward W Schlag
- Institut für Physikalische und Theoretische Chemie , TU-München , Lichtenbergstr. 4 , 85748 Garching , Germany
| | - Dah-Yen Yang
- Institute of Atomic and Molecular Sciences , Academia Sinica , Taipei 106 , Taiwan
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5
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Böhnke H, Röttger K, Ingle RA, Marroux HJB, Bohnsack M, Schwalb NK, Orr-Ewing AJ, Temps F. Electronic Relaxation Dynamics of UV-Photoexcited 2-Aminopurine-Thymine Base Pairs in Watson-Crick and Hoogsteen Conformations. J Phys Chem B 2019; 123:2904-2914. [PMID: 30875228 DOI: 10.1021/acs.jpcb.9b02361] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The fluorescent analogue 2-aminopurine (2AP) of the canonical nucleobase adenine (6-aminopurine) base-pairs with thymine (T) without disrupting the helical structure of DNA. It therefore finds frequent use in molecular biology for probing DNA and RNA structures and conformational dynamics. However, detailed understanding of the processes responsible for fluorescence quenching remains largely elusive on a fundamental level. Although attempts have been made to ascribe decreased excited-state lifetimes to intrastrand charge-transfer and stacking interactions, possible influences from dynamic interstrand H-bonding have been widely ignored. Here, we investigate the electronic relaxation of UV-excited 2AP·T in Watson-Crick (WC) and Hoogsteen (HS) conformations. Although the WC conformation features slowed-down, monomer-like electronic relaxation in τ ∼ 1.6 ns toward ground-state recovery and triplet formation, the dynamics associated with 2AP·T in the HS motif exhibit faster deactivation in τ ∼ 70 ps. As recent research has revealed abundant transient interstrand H-bonding in the Hoogsteen motif for duplex DNA, the established model for dynamic fluorescence quenching may need to be revised in the light of our results. The underlying supramolecular photophysical mechanisms are discussed in terms of a proposed excited-state double-proton transfer as an efficient deactivation channel for recovery of the HS species in the electronic ground state.
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Affiliation(s)
- Hendrik Böhnke
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
| | - Katharina Röttger
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany.,School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Rebecca A Ingle
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Hugo J B Marroux
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Mats Bohnsack
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
| | - Nina K Schwalb
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
| | - Andrew J Orr-Ewing
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Friedrich Temps
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
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6
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Affiliation(s)
- Saumyak Mukherjee
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Sayantan Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Subhajit Acharya
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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7
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Bull GD, Thompson KC. Proton Transfer and Tautomerism in 2-Aminopurine-Thymine and Pyrrolocytosine-Guanine Base Pairs. Biochemistry 2018; 57:4547-4561. [PMID: 30024730 DOI: 10.1021/acs.biochem.8b00521] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Pyrrolocytosine (PC) and 2-aminopurine (2AP) are fluorescent nucleobase analogues of the DNA nucleobases cytosine and adenine, respectively, and form base pairs with guanine and thymine. Both fluorescent nucleobases are used extensively as probes for local structure in nucleic acids as the fluorescence properties of PC and 2AP are very sensitive to changes such as helix formation, although the reasons for this sensitivity are not clear. To address this question, ab initio calculations have been used to calculate energies, at the MP2 and CIS level, of three different tautomer pairings of PC-G, and two of 2AP-T, which can potentially be interconverted by double proton transfer between the bases. Potential energy curves linking the different tautomer pairs have been calculated. For both PC-G and 2AP-T, the most stable tautomer pair in the electronic ground state is that analogous to the natural C-G and A-T base pair. In the case of 2AP-T, an alternative, stable, tautomer base pair was located in the first electronically excited state; however, it lies higher in energy than the tautomer pair analogous to A-T, making conversion to the alternative form unlikely. In contrast, in the case of PC-G, an alternative tautomer base pair is found to be the most stable form in the first electronically excited state, and this form is accessible following initial excitation from the ground state tautomer pair, thus suggesting an alternative deactivation route via double proton transfer may be possible when PC is involved in hydrogen bonding, such as occurs in helical conformations.
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Affiliation(s)
- Graham D Bull
- Department of Biological Sciences and Institute of Structural and Molecular Biology, Birkbeck , University of London , Malet Street , Bloomsbury, London WC1E 7HX , U.K
| | - Katherine C Thompson
- Department of Biological Sciences and Institute of Structural and Molecular Biology, Birkbeck , University of London , Malet Street , Bloomsbury, London WC1E 7HX , U.K
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8
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Shweta H, Sen S. Dynamics of water and ions around DNA: What is so special about them? J Biosci 2018; 43:499-518. [PMID: 30002269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Water around biomolecules is special for behaving strangely - both in terms of structure and dynamics, while ions are found to control various interactions in biomolecules such as DNA, proteins and lipids. The questions that how water and ions around these biomolecules behave in terms of their structure and dynamics, and how they affect the biomolecular functions have triggered tremendous research activities worldwide. Such activities not only unfolded important static and dynamic properties of water and ions around these biomolecules, but also provoked heated debate regarding their explanation and role in biological functions. DNA, being negatively charged, interacts strongly with the surrounding dipolar water and positively charged counterions, leading to complex electrostatic coupling of water and ions with the DNA. Recent timeresolved fluorescence Stokes shift experiments and related computer simulation studies from our and other laboratories have unfolded some unique dynamic characteristics of water and ions near different structures of DNA. These results are discussed here to showcase the specialty of water and ion dynamics around DNA.
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Affiliation(s)
- Him Shweta
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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9
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10
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Egorov GI, Makarov DM. Effect of high pressure and temperature on the volume properties of the liquid-phase mixture of {water (1) + formamide (2)}. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.01.072] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Böhnke H, Röttger K, Ingle RA, Marroux HJB, Bohnsack M, Orr-Ewing AJ, Temps F. Efficient intersystem crossing in 2-aminopurine riboside probed by femtosecond time-resolved transient vibrational absorption spectroscopy. Phys Chem Chem Phys 2018; 20:20033-20042. [DOI: 10.1039/c8cp02664e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The photophysical dynamics of 2-aminopurine, a fluorescent analogue of the canonical nucleobase adenine, has been studied by femtosecond transient vibrational absorption spectroscopy.
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Affiliation(s)
- Hendrik Böhnke
- Institute of Physical Chemistry
- Christian-Albrechts-University Kiel
- 24098 Kiel
- Germany
| | - Katharina Röttger
- Institute of Physical Chemistry
- Christian-Albrechts-University Kiel
- 24098 Kiel
- Germany
- School of Chemistry
| | | | | | - Mats Bohnsack
- Institute of Physical Chemistry
- Christian-Albrechts-University Kiel
- 24098 Kiel
- Germany
| | | | - Friedrich Temps
- Institute of Physical Chemistry
- Christian-Albrechts-University Kiel
- 24098 Kiel
- Germany
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12
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Shweta H, Singh MK, Yadav K, Verma SD, Pal N, Sen S. Effect of T·T Mismatch on DNA Dynamics Probed by Minor Groove Binders: Comparison of Dynamic Stokes Shifts of Hoechst and DAPI. J Phys Chem B 2017; 121:10735-10748. [PMID: 28922599 DOI: 10.1021/acs.jpcb.7b06937] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Recognition of DNA base mismatches and their subsequent repair by enzymes is vital for genomic stability. However, it is difficult to comprehend such a process in which enzymes sense and repair different types of mismatches with different ability. It has been suggested that the differential structural changes of mismatched bases act as cues to the repair enzymes, although the effect of such DNA structural changes on surrounding water and ion dynamics is inevitable due to strong electrostatic coupling among them. Thus, collective dynamics of DNA, water, and ions near the mismatch site is believed to be important for mismatch recognition and repair mechanism. Here we show that introduction of a T·T mismatch in the minor groove of DNA induces dispersed (collective) power-law solvation dynamics (of exponent ∼0.24), measured by monitoring the time-resolved fluorescence Stokes shifts (TRFSS) of two popular minor groove binders (Hoechst 33258 and DAPI) over five decades of time from 100 fs to 10 ns. The same ligands however sense different dynamics (power-law of exponent ∼0.15 or power-law multiplied with biexponential relaxation) in the minor groove of normal-DNA. The similar fluorescence anisotropy decays of ligands measured in normal- and T·T-DNA suggest that Stokes shift dynamics and their changes in T·T-DNA purely originate from the solvation process, and not from any internal rotational motion of probe-ligands. The dispersed power-law solvation dynamics seen in T·T-DNA indicate that the ligands do not sense any particular (exponential) relaxation specific to T·T wobbling and/or other conformational changes. This could be the reason why T·T mismatch is recognized by enzymes with lower efficiency compared to purine-pyrimidine and purine-purine mismatches.
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Affiliation(s)
- Him Shweta
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University , New Delhi 110067, India
| | - Moirangthem Kiran Singh
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University , New Delhi 110067, India
| | - Kavita Yadav
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University , New Delhi 110067, India
| | - Sachin Dev Verma
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University , New Delhi 110067, India
| | - Nibedita Pal
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University , New Delhi 110067, India
| | - Sobhan Sen
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University , New Delhi 110067, India
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13
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Abstract
The structure and function of biomolecules are strongly influenced by their hydration shells. Structural fluctuations and molecular excitations of hydrating water molecules cover a broad range in space and time, from individual water molecules to larger pools and from femtosecond to microsecond time scales. Recent progress in theory and molecular dynamics simulations as well as in ultrafast vibrational spectroscopy has led to new and detailed insight into fluctuations of water structure, elementary water motions, electric fields at hydrated biointerfaces, and processes of vibrational relaxation and energy dissipation. Here, we review recent advances in both theory and experiment, focusing on hydrated DNA, proteins, and phospholipids, and compare dynamics in the hydration shells to bulk water.
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Affiliation(s)
- Damien Laage
- École
Normale Supérieure, PSL Research University, UPMC Univ Paris
06, CNRS, Département de Chimie,
PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne
Universités, UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
| | - Thomas Elsaesser
- Max-Born-Institut
für Nichtlineare Optik und Kurzzeitspektroskopie, D-12489 Berlin, Germany
| | - James T. Hynes
- École
Normale Supérieure, PSL Research University, UPMC Univ Paris
06, CNRS, Département de Chimie,
PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne
Universités, UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
- Department
of Chemistry and Biochemistry, University
of Colorado, Boulder, Colorado 80309, United
States
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14
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Laage D, Elsaesser T, Hynes JT. Perspective: Structure and ultrafast dynamics of biomolecular hydration shells. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2017; 4:044018. [PMID: 28470026 PMCID: PMC5398927 DOI: 10.1063/1.4981019] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 03/31/2017] [Indexed: 05/25/2023]
Abstract
The structure and function of biomolecules can be strongly influenced by their hydration shells. A key challenge is thus to determine the extent to which these shells differ from bulk water, since the structural fluctuations and molecular excitations of hydrating water molecules within these shells can cover a broad range in both space and time. Recent progress in theory, molecular dynamics simulations, and ultrafast vibrational spectroscopy has led to new and detailed insight into the fluctuations of water structure, elementary water motions, and electric fields at hydrated biointerfaces. Here, we discuss some central aspects of these advances, focusing on elementary molecular mechanisms and processes of hydration on a femto- to picosecond time scale, with some special attention given to several issues subject to debate.
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Affiliation(s)
- Damien Laage
- Ecole Normale Supérieure, PSL Research University, UPMC Univ Paris 06, CNRS, Départment de Chimie, PASTEUR, 24 rue Lhomond, 75005 Paris, France
| | - Thomas Elsaesser
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, 12489 Berlin, Germany
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15
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Paul S, Ahmed T, Samanta A. Influence of Divalent Counterions on the Dynamics in DNA as Probed by Using a Minor-Groove Binder. Chemphyschem 2017; 18:2058-2064. [DOI: 10.1002/cphc.201700251] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Sneha Paul
- School of Chemistry; University of Hyderabad; Hyderabad 500046 India
| | - Tasnim Ahmed
- School of Chemistry; University of Hyderabad; Hyderabad 500046 India
| | - Anunay Samanta
- School of Chemistry; University of Hyderabad; Hyderabad 500046 India
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16
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Kolář MH, Kubař T. Reaction Path Averaging: Characterizing the Structural Response of the DNA Double Helix to Electron Transfer. J Phys Chem B 2017; 121:1520-1532. [PMID: 28121443 DOI: 10.1021/acs.jpcb.6b12109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A polarizable environment, prominently the solvent, responds to electronic changes in biomolecules rapidly. The knowledge of conformational relaxation of the biomolecule itself, however, may be scarce or missing. In this work, we describe in detail the structural changes in DNA undergoing electron transfer between two adjacent nucleobases. We employ an approach based on averaging of tens to hundreds of thousands of nonequilibrium trajectories generated with molecular dynamics simulation, and a reduction of dimensionality suitable for DNA. We show that the conformational response of the DNA proceeds along a single collective coordinate that represents the relative orientation of two consecutive base pairs, namely, a combination of helical parameters shift and tilt. The structure of DNA relaxes on time scales reaching nanoseconds, contributing marginally to the relaxation of energies, which is dominated by the modes of motion of the aqueous solvent. The concept of reaction path averaging (RPA), conveniently exploited in this context, makes it possible to filter out any undesirable noise from the nonequilibrium data, and is applicable to any chemical process in general.
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Affiliation(s)
- Michal H Kolář
- Institute for Advanced Simulations (IAS-5) and Institute of Neuroscience and Medicine (INM-9), Forschungszentrum Jülich , 52428 Jülich, Germany.,Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences , 16610 Praha, Czech Republic
| | - Tomáš Kubař
- Institute of Physical Chemistry & Center for Functional Nanostructures, Karlsruhe Institute of Technology , 76131 Karlsruhe, Germany
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17
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Gu X, Park SY, Tonelli M, Cornilescu G, Xia T, Zhong D, Schroeder SJ. NMR Structures and Dynamics in a Prohead RNA Loop that Binds Metal Ions. J Phys Chem Lett 2016; 7:3841-3846. [PMID: 27631837 PMCID: PMC5762182 DOI: 10.1021/acs.jpclett.6b01465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Metal ions are critical for RNA structure and enzymatic activity. We present the structure of an asymmetric RNA loop that binds metal ions and has an essential function in a bacteriophage packaging motor. Prohead RNA is a noncoding RNA that is required for genome packaging activity in phi29-like bacteriophage. The loops in GA1 and phi29 bacteriophage share a conserved adenine that forms a base triple, although the structural context for the base triple differs. NMR relaxation studies and femtosecond time-resolved fluorescence spectroscopy reveal the dynamic behavior of the loop in the metal ion bound and unbound forms. The mechanism of metal ion binding appears to be an induced conformational change between two dynamic ensembles rather than a conformational capture mechanism. These results provide experimental benchmarks for computational models of RNA-metal ion interactions.
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Affiliation(s)
- Xiaobo Gu
- Department of Chemistry & Biochemistry and Department of Microbiology & Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Sun-Young Park
- Department of Physics, Ohio State University, Columbus, Ohio 43210, United States
| | - Marco Tonelli
- NMRFAM, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Gabriel Cornilescu
- NMRFAM, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Tianbing Xia
- Department of Molecular and Cell Biology, University of Texas, Dallas, Texas 75080, United States
| | - Dongping Zhong
- Department of Physics, Ohio State University, Columbus, Ohio 43210, United States
| | - Susan J. Schroeder
- Department of Chemistry & Biochemistry and Department of Microbiology & Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States
- Corresponding Author.
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18
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Singh MK, Shweta H, Sen S. Dispersed dynamics of solvation in G-quadruplex DNA: comparison of dynamic Stokes shifts of probes in parallel and antiparallel quadruplex structures. Methods Appl Fluoresc 2016; 4:034009. [PMID: 28355155 DOI: 10.1088/2050-6120/4/3/034009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
G-quadruplex DNA (GqDNA) structures play an important role in many specific cellular functions and are promising anti-tumor targets for small molecules (ligands). Here, we measured the dynamic Stokes shift of a ligand (Hoechst) bound to parallel c-Myc (mPu22) GqDNA over five decades of time from 100 fs to 10 ns, and compared it with the previously reported dynamics of DAPI bound to antiparallel human telomeric (hTelo22) GqDNA (Pal et al 2015 J. Phys. Chem. Lett. 6 1754). Stokes shift data from fluorescence up-conversion and time-correlated single photon counting experiments was combined to cover the broad dynamic range. The results show that the solvation dynamics of Hoechst in parallel mPu22 GqDNA follow a power law relaxation, added to fast 2 ps exponential relaxation, from 100 fs to 10 ns, with only a subtle difference of power law exponents in the two ligand-GqDNA systems (0.06 in Hoechst-mPu22 compared to 0.16 in DAPI-hTelo22). We measured steady-state fluorescence spectra and time-resolved anisotropy decays which confirm the tight binding of Hoechst to parallel mPu22 with a binding constant of ~1 × 105 M-1. The molecular docking of Hoechst in parallel GqDNA followed by a 50 ns molecular dynamics (MD) simulation on a Hoechst-GqDNA complex reveals that Hoechst binds to one of the outer G-tetrads by end-stacking near G13 and G4, which is different from the binding site of DAPI inside a groove of antiparallel hTelo22 GqDNA. Reconciling previous experimental and simulation results, we assign the 2 ps component to the hydration dynamics of only weakly perturbed water near mPu22 and the power law relaxation to the coupled motion of water and DNA (i.e. DNA backbone, unpaired bases and loops connecting G-tetrads) which come near the Hoechst inside parallel GqDNA.
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Affiliation(s)
- Moirangthem Kiran Singh
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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19
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Fathi S, Gonzalez MA, Bahri M, Nasr S. Structural investigations of liquid formamide by x-ray scattering, ab-initio calculations and molecular dynamics simulations. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.01.098] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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Duboué-Dijon E, Fogarty AC, Hynes JT, Laage D. Dynamical Disorder in the DNA Hydration Shell. J Am Chem Soc 2016; 138:7610-20. [DOI: 10.1021/jacs.6b02715] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Elise Duboué-Dijon
- École Normale
Supérieure, PSL Research University, UPMC Univ Paris 06, CNRS,
Département de Chimie, PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne Universités,
UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
| | - Aoife C. Fogarty
- École Normale
Supérieure, PSL Research University, UPMC Univ Paris 06, CNRS,
Département de Chimie, PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne Universités,
UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
| | - James T. Hynes
- École Normale
Supérieure, PSL Research University, UPMC Univ Paris 06, CNRS,
Département de Chimie, PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne Universités,
UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Damien Laage
- École Normale
Supérieure, PSL Research University, UPMC Univ Paris 06, CNRS,
Département de Chimie, PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne Universités,
UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
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21
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Roy A, Dutta R, Kundu N, Banik D, Sarkar N. A Comparative Study of the Influence of Sugars Sucrose, Trehalose, and Maltose on the Hydration and Diffusion of DMPC Lipid Bilayer at Complete Hydration: Investigation of Structural and Spectroscopic Aspect of Lipid-Sugar Interaction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:5124-5134. [PMID: 27133799 DOI: 10.1021/acs.langmuir.6b01115] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
It is well-known that sugars protect membrane structures against fusion and leakage. Here, we have investigated the interaction between different sugars (sucrose, trehalose, and maltose) and phospholipid membrane of 1,2-dimyristoyl-sn-glycero-3-phoshpocholine (DMPC) using dynamic light scattering (DLS), transmission electron microscopy (TEM), and other various spectroscopic techniques. DLS measurement reveals that the addition of sugar molecule results a significant increase of the average diameter of DMPC membrane. We have also noticed that in the presence of different sugars the rotational relaxation and solvation time of coumarin 480 (C480) and coumarin 153 (C153) surrounding DMPC membrane increases, suggesting a marked reduction of the hydration behavior at the surface of phospholipid membrane. In addition, we have also investigated the effect of sugar molecules on the lateral mobility of phospholipids. Interestingly, the relative increase in rotational, solvation and lateral diffusion is more prominent for C480 than that of C153 because of their different location in lipid bilayer. It is because of preferential location of comparatively hydrophilic probe C480 in the interfacial region of the lipid bilayer. Sugars intercalate with the phospholipid headgroup through hydrogen bonding and replace smaller sized water molecules from the membrane surface. Therefore, overall, we have monitored a comparative analysis regarding the interaction of different sugar molecules (sucrose, trehalose, and maltose) with the DMPC membrane through DLS, TEM, solvation dynamics, time-resolved anisotropy, and fluorescence correlation spectroscopy (FCS) measurements to explore the structural and spectroscopic aspect of lipid-sugar interaction.
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Affiliation(s)
- Arpita Roy
- Department of Chemistry, Indian Institute of Technology , Kharagpur 721302, WB, India
| | - Rupam Dutta
- Department of Chemistry, Indian Institute of Technology , Kharagpur 721302, WB, India
| | - Niloy Kundu
- Department of Chemistry, Indian Institute of Technology , Kharagpur 721302, WB, India
| | - Debasis Banik
- Department of Chemistry, Indian Institute of Technology , Kharagpur 721302, WB, India
| | - Nilmoni Sarkar
- Department of Chemistry, Indian Institute of Technology , Kharagpur 721302, WB, India
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22
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Samanta S, Raghunathan D, Mukherjee S. Effect of temperature on the structure and hydration layer of TATA-box DNA: A molecular dynamics simulation study. J Mol Graph Model 2016; 66:9-19. [PMID: 27017424 DOI: 10.1016/j.jmgm.2016.03.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 03/17/2016] [Accepted: 03/21/2016] [Indexed: 01/25/2023]
Abstract
DNA within the living cells experiences a diverse range of temperature, ranging from freezing condition to hot spring water. How the structure, the mechanical properties of DNA, and the solvation dynamics around DNA changes with the temperature is important to understand the functionality of DNA under those acute temperature conditions. In that notion, we have carried out molecular dynamics simulations of a DNA oligomer, containing TATA-box sequence for three different temperatures (250K, 300K and 350K). We observed that the structure of the DNA, in terms of backbone torsion angles, sugar pucker, base pair parameters, and base pair step parameters, did not show any unusual properties within the studied range of temperatures, but significant structural alteration was noticed between BI and BII forms at higher temperature. As expected, the flexibility of the DNA, in terms of the torsional rigidity and the bending rigidity is highly temperature dependent, confirming that flexibility increases with increase in temperature. Additionally, the groove widths of the studied DNA showed temperature sensitivity, specifically, the major groove width decreases and the minor groove width increases, respectively, with the increase in temperature. We observed that at higher temperature, water around both the major and the minor groove of the DNA is less structured. However, the water dynamics around the minor groove of the DNA is more restricted as compared to the water around the major groove throughout the studied range of temperatures, without any anomalous behavior.
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Affiliation(s)
- Sudipta Samanta
- BioSystems and Micromechanics IRG (BioSyM), Singapore-MIT Alliance for Research and Technology (SMART), 1 Create Way, 117543, Republic of Singapore; Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Devanathan Raghunathan
- Prochem Solutions Pte. Ltd., 89C Science Park Drive, The Rutherford, # 04-13, Singapore Science Park 1, 118261, Singapore
| | - Sanchita Mukherjee
- Indian Institute of Science Education and Research, Kolkata, Mohanpur, West Bengal, 741246, India
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23
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Lin SH, Fujitsuka M, Majima T. Excess-Electron Transfer in DNA by a Fluctuation-Assisted Hopping Mechanism. J Phys Chem B 2016; 120:660-6. [DOI: 10.1021/acs.jpcb.5b10857] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Shih-Hsun Lin
- The Institute of Scientific
and Industrial Research (SANKEN), Osaka University, Mihogaoka
8-1, Ibaraki, Osaka 567-0047, Japan
| | - Mamoru Fujitsuka
- The Institute of Scientific
and Industrial Research (SANKEN), Osaka University, Mihogaoka
8-1, Ibaraki, Osaka 567-0047, Japan
| | - Tetsuro Majima
- The Institute of Scientific
and Industrial Research (SANKEN), Osaka University, Mihogaoka
8-1, Ibaraki, Osaka 567-0047, Japan
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24
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Choudhury S, Ghosh B, Singh P, Ghosh R, Roy S, Pal SK. Ultrafast differential flexibility of Cro-protein binding domains of two operator DNAs with different sequences. Phys Chem Chem Phys 2016; 18:17983-90. [DOI: 10.1039/c6cp02522f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The crucial ultrafast domain fluctuation of the operator DNA OR3 over OR2 upon complexation with the repressor Cro-protein dimer has been investigated.
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Affiliation(s)
- Susobhan Choudhury
- Department of Chemical
- Biological & Macromolecular Sciences
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 098
- India
| | - Basusree Ghosh
- Division of Structural Biology and Bioinformatics
- Indian Institute of Chemical Biology
- Kolkata 700 032
- India
| | - Priya Singh
- Department of Chemical
- Biological & Macromolecular Sciences
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 098
- India
| | - Raka Ghosh
- Division of Structural Biology and Bioinformatics
- Indian Institute of Chemical Biology
- Kolkata 700 032
- India
| | - Siddhartha Roy
- Division of Structural Biology and Bioinformatics
- Indian Institute of Chemical Biology
- Kolkata 700 032
- India
| | - Samir Kumar Pal
- Department of Chemical
- Biological & Macromolecular Sciences
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 098
- India
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25
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Dehmel L, Berndt F, Weinberger M, Sajadi M, Ioffe I, Wagenknecht HA, Ernsting NP. Isosteric and fluorescent DNA base pair formed by 4-amino-phthalimide and 2,4-diaminopyrimidine: melting, structure, and THz polar solvation dynamics. Phys Chem Chem Phys 2016; 18:6813-20. [DOI: 10.1039/c5cp06972f] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
An artificial base pair in duplex DNA, formed by 2,4-diaminopyrimidine and fluorescent 4-aminophthalimide C-nucleosides, is characterized spectroscopically, for use in femtosecond solvation dynamics.
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Affiliation(s)
- L. Dehmel
- Department of Chemistry
- Humboldt-Universität zu Berlin
- 12489 Berlin
- Germany
| | - F. Berndt
- Department of Chemistry
- Humboldt-Universität zu Berlin
- 12489 Berlin
- Germany
| | - M. Weinberger
- Institute of Organic Chemistry
- Karlsruhe Institute of Technology (KIT)
- 76131 Karlsruhe
- Germany
| | - M. Sajadi
- Department of Chemistry
- Humboldt-Universität zu Berlin
- 12489 Berlin
- Germany
| | - I. Ioffe
- Department of Chemistry
- Lomonosov Moscow State University
- Moscow
- Russia
| | - H.-A. Wagenknecht
- Institute of Organic Chemistry
- Karlsruhe Institute of Technology (KIT)
- 76131 Karlsruhe
- Germany
| | - N. P. Ernsting
- Department of Chemistry
- Humboldt-Universität zu Berlin
- 12489 Berlin
- Germany
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26
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Fathi S, Gonzalez MA, Bahri M, Nasr S, Bellissent-Funel MC. Structural investigation of liquid formic acid by X-ray and neutron scattering, ab initio calculations and molecular dynamics simulations. J Mol Liq 2015. [DOI: 10.1016/j.molliq.2015.03.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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27
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Verma SD, Pal N, Singh MK, Sen S. Sequence-Dependent Solvation Dynamics of Minor-Groove Bound Ligand Inside Duplex-DNA. J Phys Chem B 2015; 119:11019-29. [DOI: 10.1021/acs.jpcb.5b01977] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Sachin Dev Verma
- Spectroscopy Laboratory,
School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Nibedita Pal
- Spectroscopy Laboratory,
School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Moirangthem Kiran Singh
- Spectroscopy Laboratory,
School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sobhan Sen
- Spectroscopy Laboratory,
School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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28
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Pal N, Shweta H, Singh MK, Verma SD, Sen S. Power-Law Solvation Dynamics in G-Quadruplex DNA: Role of Hydration Dynamics on Ligand Solvation inside DNA. J Phys Chem Lett 2015; 6:1754-1760. [PMID: 26263345 DOI: 10.1021/acs.jpclett.5b00653] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
G-quadruplex DNA (GqDNA) structures act as promising anticancer targets for small-molecules (ligands). Solvation dynamics of a ligand (DAPI: 4',6-diamidino-2-phenylindole) inside antiparallel-GqDNA is studied through direct comparison of time-resolved experiments to molecular dynamics (MD) simulation. Dynamic Stokes shifts of DAPI in GqDNA prepared in H2O buffer and D2O are compared to find the effect of water on ligand solvation. Experimental dynamics (in H2O) is then directly compared with the dynamics computed from 65 ns simulation on the same DAPI-GqDNA complex. Ligand solvation follows power-law relaxation (summed with fast exponential relaxation) from ~100 fs to 10 ns. Simulation results show relaxation below ~5 ps is dominated by water motion, while both water and DNA contribute comparably to dictate long-time power-law dynamics. Ion contribution is, however, found to be negligible. Simulation results also suggest that anomalous solvation dynamics may have origin in subdiffusive motion of perturbed water near GqDNA.
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Affiliation(s)
- Nibedita Pal
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Him Shweta
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Moirangthem Kiran Singh
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sachin Dev Verma
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sobhan Sen
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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29
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Son H, Choi DH, Jung S, Park J, Park GS. Dielectric relaxation of hydration water in the Dickerson–Drew duplex solution probed by THz spectroscopy. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.03.054] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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30
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Roy S, Yashonath S, Bagchi B. Mode coupling theory analysis of electrolyte solutions: Time dependent diffusion, intermediate scattering function, and ion solvation dynamics. J Chem Phys 2015; 142:124502. [DOI: 10.1063/1.4915274] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Affiliation(s)
- Susmita Roy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Subramanian Yashonath
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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31
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Izanloo C. Investigation of changes in the arrangement of water molecules and salt ions surrounding different atoms of the DNA molecule during the melting process: a molecular dynamics simulation study. CAN J CHEM 2015. [DOI: 10.1139/cjc-2014-0371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A molecular dynamics simulation was performed on a B-DNA duplex (CGCGAATTGCGC) at different temperatures. The DNA was immerged in a saltwater medium with 1 mol/L NaCl concentration. The arrangements of water molecules and cations around the different atoms of DNA on the melting pathway were investigated. Almost for all atoms of the DNA by double helix → single-stranded transition, the water molecules released from the DNA duplex and cations were close to single-stranded DNA, but this behavior was not clearly seen at melting temperatures. Therefore, release of water molecules and cations approaching the DNA by the increase of temperature does not have any effect on the sharpness of the transition curve. Most of the water molecules and cations were found to be around the negatively charged phosphate oxygen atoms. The number of water molecules released from the first shell hydration upon melting in the minor groove was higher than in the major groove, and intrusion of cations into the minor groove after melting was higher than into the major groove. The hydrations of imino protons were different from each other and were dependent on DNA bases.
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Affiliation(s)
- C. Izanloo
- Department of Chemistry, Bojnord Branch, Islamic Azad University, Bojnord, Iran
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32
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Structural states of the flexible catalytic loop of M. tuberculosis tyrosyl-tRNA synthetase in different enzyme–substrate complexes. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2014; 43:613-22. [DOI: 10.1007/s00249-014-0991-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 09/17/2014] [Accepted: 09/28/2014] [Indexed: 10/24/2022]
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33
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Switching on the fluorescence of 2-aminopurine by site-selective microhydration. Nat Chem 2014; 6:989-93. [DOI: 10.1038/nchem.2086] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Accepted: 09/11/2014] [Indexed: 11/08/2022]
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34
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Bagchi B. Anomalous power law decay in solvation dynamics of DNA: a mode coupling theory analysis of ion contribution. Mol Phys 2014. [DOI: 10.1080/00268976.2014.904943] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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35
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Paytakov G, Gorb L, Stepanyugin A, Samiylenko S, Hovorun D, Leszczynski J. Homodimers of Cytosine and 1-MethylCytosine. A DFT study of geometry, relative stability and H-NMR shifts in gas-phase and selected solvents. J Mol Model 2014; 20:2115. [DOI: 10.1007/s00894-014-2115-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Accepted: 12/13/2013] [Indexed: 12/07/2022]
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36
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Lobsiger S, Sinha RK, Leutwyler S. Building Up Water-Wire Clusters: Isomer-Selective Ultraviolet and Infrared Spectra of Jet-Cooled 2-Aminopurine (H2O)n, n = 2 and 3. J Phys Chem B 2013; 117:12410-21. [DOI: 10.1021/jp407127c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Simon Lobsiger
- Department
of Chemistry and Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
- Department
of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904-4319, United States
| | - Rajeev K. Sinha
- Department
of Chemistry and Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
- Department
of Atomic and Molecular Physics, Manipal University, Manipal-576104, Karnataka, India
| | - Samuel Leutwyler
- Department
of Chemistry and Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
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37
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Polley D, Patra A, Mitra RK. Dielectric relaxation of the extended hydration sheathe of DNA in the THz frequency region. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.09.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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38
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Reichardt C, Wen C, Vogt RA, Crespo-Hernández CE. Role of intersystem crossing in the fluorescence quenching of 2-aminopurine 2′-deoxyriboside in solution. Photochem Photobiol Sci 2013; 12:1341-50. [DOI: 10.1039/c3pp25437b] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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39
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Lee SA, Tao NJ, Rupprecht A. A Raman scattering study of the interactions of DNA with its water of hydration. J Biomol Struct Dyn 2012; 31:1337-42. [PMID: 23140399 DOI: 10.1080/07391102.2012.736759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Raman spectroscopy is used to probe the nature of the hydrogen bonds which hold the water of hydration to DNA. The ∼ 3450 cm(-1) molecular O-H stretching mode shows that the first six water molecules per base pair of the primary hydration shell are very strongly bound to the DNA. The observed shift in the peak position of this mode permits a determination of the length of the hydrogen bonds for these water molecules. These hydrogen bonds appear to be about 0.3 Å shorter than the hydrogen bonds in bulk water. The linewidth of this mode shows no significant changes above water contents of about 15 water molecules per base pair. This technique of using a vibrational spectroscopy to obtain structural information about the hydration shells of DNA could be used to study the hydration shells of other biomolecules.
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Affiliation(s)
- Scott A Lee
- a Department of Physics & Astronomy , University of Toledo , M.S. #111, Toledo , OH , 43606 , USA
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40
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Dixit SB, Mezei M, Beveridge DL. Studies of base pair sequence effects on DNA solvation based on all-atom molecular dynamics simulations. J Biosci 2012; 37:399-421. [PMID: 22750979 DOI: 10.1007/s12038-012-9223-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Detailed analyses of the sequence-dependent solvation and ion atmosphere of DNA are presented based on molecular dynamics (MD) simulations on all the 136 unique tetranucleotide steps obtained by the ABC consortium using the AMBER suite of programs. Significant sequence effects on solvation and ion localization were observed in these simulations. The results were compared to essentially all known experimental data on the subject. Proximity analysis was employed to highlight the sequence dependent differences in solvation and ion localization properties in the grooves of DNA. Comparison of the MD-calculated DNA structure with canonical A- and B-forms supports the idea that the G/C-rich sequences are closer to canonical A- than B-form structures, while the reverse is true for the poly A sequences, with the exception of the alternating ATAT sequence. Analysis of hydration density maps reveals that the flexibility of solute molecule has a significant effect on the nature of observed hydration. Energetic analysis of solute-solvent interactions based on proximity analysis of solvent reveals that the GC or CG base pairs interact more strongly with water molecules in the minor groove of DNA that the AT or TA base pairs, while the interactions of the AT or TA pairs in the major groove are stronger than those of the GC or CG pairs. Computation of solvent-accessible surface area of the nucleotide units in the simulated trajectories reveals that the similarity with results derived from analysis of a database of crystallographic structures is excellent. The MD trajectories tend to follow Manning's counterion condensation theory, presenting a region of condensed counterions within a radius of about 17 A from the DNA surface independent of sequence. The GC and CG pairs tend to associate with cations in the major groove of the DNA structure to a greater extent than the AT and TA pairs. Cation association is more frequent in the minor groove of AT than the GC pairs. In general, the observed water and ion atmosphere around the DNA sequences is the MD simulation is in good agreement with experimental observations.
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Affiliation(s)
- Surjit B Dixit
- Chemistry Department and Molecular Biophysics Program, Wesleyan University, Middletown, CT 06457, USA
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Verma SD, Pal N, Singh MK, Sen S. Probe Position-Dependent Counterion Dynamics in DNA: Comparison of Time-Resolved Stokes Shift of Groove-Bound to Base-Stacked Probes in the Presence of Different Monovalent Counterions. J Phys Chem Lett 2012; 3:2621-2626. [PMID: 26295881 DOI: 10.1021/jz300934x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Time-resolved fluorescence Stokes shifts (TRFSS) of 4',6-diamidino-2-phenylindole (DAPI) inside the minor groove of DNA are measured in the presence of three different monovalent counterions: sodium (Na(+)), rubidium (Rb(+)), and tetrabutylammonium (TBA(+)). Fluorescence up-conversion and time-correlated single photon counting are combined to obtain the time-resolved emission spectra (TRES) of DAPI in DNA from 100 fs to 10 ns. Time-resolved Stokes shift data suggest that groove-bound DAPI can not sense the counterion dynamics because the ions are displaced by DAPI far from the probe-site. However, when these results are compared to the earlier base-stacked coumarin data, the same ions are found to affect the nanosecond dynamics significantly. This suggests that the ions come close to the probe-site, such that they can affect the dynamics when measured by base-stacked coumarin. These results support previous molecular dynamics (MD) simulation data of groove-bound and base-stacked probes inside DNA.
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Affiliation(s)
- Sachin Dev Verma
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Nibedita Pal
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Moirangthem Kiran Singh
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sobhan Sen
- Spectroscopy Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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Wincel H. Gas-phase hydration thermochemistry of sodiated and potassiated nucleic acid bases. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:1479-87. [PMID: 22821196 PMCID: PMC3414711 DOI: 10.1007/s13361-012-0436-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 06/10/2012] [Accepted: 06/15/2012] [Indexed: 06/01/2023]
Abstract
Hydration reactions of sodiated and potassiated nucleic acid bases (uracil, thymine, cytosine, and adenine) produced by electrospray have been studied in a gas phase using the pulsed ion-beam high-pressure mass spectrometer. The thermochemical properties, ΔH(o)(n), ΔS(o)(n), and ΔG(o)(n), for the hydrated systems were obtained from hydration equilibrium measurement. The structural aspects of the hydrated complexes are discussed in conjunction with available literature data. The correlation between water binding energies in the hydrated complexes and the corresponding metal ion affinities of nucleobases suggests that a significant (if not dominant) amount of the canonical structure of cytosine undergoes tautomerization during electrospray ionization, and the thermochemical values for cationized cytosine probably correspond to a mixture of tautomeric complexes.
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Affiliation(s)
- Henryk Wincel
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland.
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Berndt F, Ioffe I, Granovsky AA, Mahrwald R, Tannert S, Kovalenko SA, Ernsting NP. 7-Amino-dibenzofuran-3-carboxylate: A new probe for femtosecond dynamic microsolvation studies of biomolecules. J Photochem Photobiol A Chem 2012. [DOI: 10.1016/j.jphotochem.2012.02.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cornicchi E, Sebastiani F, De Francesco A, Orecchini A, Paciaroni A, Petrillo C, Sacchetti F. Collective density fluctuations of DNA hydration water in the time-window below 1 ps. J Chem Phys 2011; 135:025101. [PMID: 21766968 DOI: 10.1063/1.3609101] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The coherent density fluctuations propagating through DNA hydration water were studied by neutron scattering spectroscopy. Two collective modes were found to be sustained by the aqueous solvent: a propagating excitation, characterised by a speed of about 3500 m/s, and another one placed at about 6 meV. These results globally agree with those previously found for the coherent excitations in bulk water, although in DNA hydration water the speed of propagating modes is definitely higher than that of the pure solvent. The short-wavelength collective excitations of DNA hydration water are reminiscent of those observed in protein hydration water and in the amorphous forms of ice.
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Affiliation(s)
- Elena Cornicchi
- Dipartimento di Fisica, Università degli Studi di Perugia, Via Pascoli, I-06123 Perugia, Italy.
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Nguyen HN, Zhao L, Gray CW, Gray DM, Xia T. Ultrafast fluorescence decay profiles reveal differential unstacking of 2-aminopurine from neighboring bases in single-stranded DNA-binding protein subsites. Biochemistry 2011; 50:8989-9001. [PMID: 21916413 DOI: 10.1021/bi2006543] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Gene 5 protein (g5p) is a dimeric single-stranded DNA-binding protein encoded by Ff strains of Escherichia coli bacteriophages. The 2-fold rotationally symmetric binding sites of a g5p dimer each bind to four nucleotides, and the dimers bind with high cooperativity to saturate antiparallel single-stranded DNA (ssDNA) strands. Ultrafast time-resolved fluorescence spectroscopies were used to investigate the conformational heterogeneity and dynamics of fluorescent 2-aminopurine (2AP) labels sequestered by bound g5p. The 2AP labels were positioned within the noncomplementary antiparallel tail sequences of d(AC)(8) or d(AC)(9) of hairpin constructs so that each fluorescent label could probe a different subsite location within the DNA-binding site of g5p. Circular dichroism and isothermal calorimetric titrations yielded binding stoichiometries of approximately six dimers per oligomer hairpin when tails were of these lengths. Mobility shift assays demonstrated the formation of a single type of g5p-saturated complex. Femtosecond time-resolved fluorescence spectroscopy showed that the 2AP in the free (non-protein-bound) DNAs had similar heterogeneous distributions of conformations. However, there were significant changes, dominated by a large increase in the population of unstacked bases from ~22 to 59-68%, depending on their subsite locations, when the oligomers were saturated with g5p. Anisotropy data indicated that 2AP in the bound state was less flexible than in the free oligomer. A control oligomer was labeled with 2AP in the loop of the hairpin and showed no significant change in its base stacking upon g5p binding. A proposed model summarizes the data.
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Affiliation(s)
- Hieu-Ngoc Nguyen
- Department of Molecular and Cell Biology, The University of Texas at Dallas, Richardson, Texas 75080-3021, United States
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Wilmink GJ, Ibey BL, Tongue T, Schulkin B, Laman N, Peralta XG, Roth CC, Cerna CZ, Rivest BD, Grundt JE, Roach WP. Development of a compact terahertz time-domain spectrometer for the measurement of the optical properties of biological tissues. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:047006. [PMID: 21529096 DOI: 10.1117/1.3570648] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Terahertz spectrometers and imaging systems are currently being evaluated as biomedical tools for skin burn assessment. These systems show promise, but due to their size and weight, they have restricted portability, and are impractical for military and battlefield settings where space is limited. In this study, we developed and tested the performance of a compact, light, and portable THz time-domain spectroscopy (THz-TDS) device. Optical properties were collected with this system from 0.1 to 1.6 THz for water, ethanol, and several ex vivo porcine tissues (muscle, adipose, skin). For all samples tested, we found that the index of refraction (n) decreases with frequency, while the absorption coefficient (μ(a)) increases with frequency. Muscle, adipose, and frozen/thawed skin samples exhibited comparable n values ranging between 2.5 and 2.0, whereas the n values for freshly harvested skin were roughly 40% lower. Additionally, we found that the freshly harvested samples exhibited higher μ(a) values than the frozen/thawed skin samples. Overall, for all liquids and tissues tested, we found that our system measured optical property values that were consistent with those reported in the literature. These results suggest that our compact THz spectrometer performed comparable to its larger counterparts, and therefore may be a useful and practical tool for skin health assessment.
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Affiliation(s)
- Gerald J Wilmink
- Air Force Research Laboratory, 711 Human Performance Wing, Human Effectiveness Directorate, Radio Frequency Radiation Branch, 8262 Hawks Road, Brooks City-Base, Texas 78235, USA.
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Furse KE, Corcelli SA. Effects of an unnatural base pair replacement on the structure and dynamics of DNA and neighboring water and ions. J Phys Chem B 2011; 114:9934-45. [PMID: 20614919 DOI: 10.1021/jp105761b] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Incorporating small molecule probes into biomolecular systems to report on local structure and dynamics is a powerful strategy that underlies a wide variety of experimental techniques, including fluorescence, electron paramagnetic resonance (EPR), and Forster resonance energy transfer (FRET) measurements. When an unnatural probe is inserted into a protein or DNA, the degree to which the presence of the probe has perturbed the local structure and dynamics it was intended to study is always an important concern. Here, molecular dynamics (MD) simulations are used to systematically study the effect of replacing a DNA base pair with a fluorescent probe, coumarin 102 deoxyriboside, at six unique sites along an A-tract DNA dodecamer. While the overall structure of the DNA oligonucleotide remains intact, replacement of A*T base pairs leads to widespread structural and dynamic perturbations up to four base pairs away from the probe site, including widening of the minor groove and increased DNA flexibility. New DNA conformations, not observed in the native sequence, are sometimes found in the vicinity of the probe and its partner abasic site analog. Strong correlations are demonstrated between DNA surface topology and water mobility.
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Affiliation(s)
- K E Furse
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Affiliation(s)
- Kristina E. Furse
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Steven A. Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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Szyc Ł, Yang M, Elsaesser T. Ultrafast energy exchange via water-phosphate interactions in hydrated DNA. J Phys Chem B 2010; 114:7951-7. [PMID: 20481569 DOI: 10.1021/jp101174q] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The ionic phosphate groups in the DNA backbone play a key role for DNA hydration. We study ultrafast vibrational dynamics and local interactions of phosphate groups and water by femtosecond two-color pump-probe spectroscopy. The asymmetric (PO(2))(-) stretching vibration nu(AS)(PO(2))(-) of artificial DNA oligomers containing 23 alternating adenine-thymine base pairs displays a lifetime of 340 fs, independent of the hydration level. For DNA at zero relative humidity, excess energy from the decay of the phosphate excitation is transferred within DNA on a 20 ps time scale. For fully hydrated DNA, the water shells around the phosphates serve as a primary heat sink accepting vibrational excess energy from DNA on a femtosecond time scale. OH stretching excitation of water molecules around fully hydrated DNA induces an ultrafast nu(AS)(PO(2))(-) response which includes rearrangements of the hydration shell and a reduction of the average number of phosphate-water hydrogen bonds.
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Affiliation(s)
- Łukasz Szyc
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, D-12489 Berlin, Germany
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