1
|
Kwon YH, Joh YA, Leonard BM, Balaz M, Varga K. Threonine functionalized colloidal cadmium sulfide (CdS) quantum dots: the role of solvent and counterion in ligand included chiroptical properties. J Colloid Interface Sci 2023; 642:771-778. [PMID: 37037081 PMCID: PMC10164713 DOI: 10.1016/j.jcis.2023.03.177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 03/21/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023]
Abstract
The functionalization of semiconductor nanocrystals, quantum dots (QDs), with small organic molecules has been studied extensively to gain better knowledge on how to tune the electronic, optical and chiroptical properties of QDs. Chiral QDs have progressively emerged as key materials in a vast range of applications including biosensing and biorecognition, imaging, asymmetric catalysis, optoelectronic devices, and spintronics. To engage the full potential of the unique properties of chiral nanomaterials and be able to prepare them with tailorable chiroptical characteristics, it is essential to understand how chirality is rendered from chiral molecular ligands at the surface of nanocrystals to the electronic states of QDs. Using a series of polar protic and aprotic solvents together with ammonium (NH4+), tetramethylammonium (TMA+), and tetrabutylammonium (TBA+) countercations in the preparation of threonine-functionalized cadmium sulfide (Thr-CdS) QDs by phase transfer ligand exchange approach, we demonstrated the significance of the role both the solvent and the countercations play in the transfer of chirality from chiral molecular ligand to achiral semiconductor QDs as apparent by the modulations of the signatures and anisotropy of the circular dichroism (CD) spectra. Moreover, we have utilized tetrabutylammonium countercation to successfully synthesize chiral QDs in nonpolar cyclohexane solvent for the first time. This study provides further insights into the origin of the ligand induced chirality of colloidal nanomaterials and facilitates the synthesis of tailormade chiral QDs.
Collapse
|
2
|
Varga K, Elliott KW, Nordyke C, Sreter JA, Jovic K, Brown LM. Biophysical characterization and applications of an insect antifreeze protein. Biophys J 2023; 122:11a. [PMID: 36782525 DOI: 10.1016/j.bpj.2022.11.289] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Affiliation(s)
- Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Korth W Elliott
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Christopher Nordyke
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Jonathan A Sreter
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Katarina Jovic
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Logan M Brown
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| |
Collapse
|
3
|
Jovic K, Brown L, Vashisth H, Varga K. Inhibition of the SARS-CoV-2 main protease by a thiadiazolidinone derivative. Biophys J 2023; 122:340a. [PMID: 36783723 DOI: 10.1016/j.bpj.2022.11.1892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Affiliation(s)
- Katarina Jovic
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Logan Brown
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Harish Vashisth
- Department of Chemical Engineering, University of New Hampshire, Durham, NH, USA
| | - Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| |
Collapse
|
4
|
Brown LM, Elliott KW, Nordyke CT, Sreter JA, Jović K, Baures PW, Tsavalas JG, Varga K. Structural and functional characterization of antifreeze protein APAFP752. Cryobiology 2022. [DOI: 10.1016/j.cryobiol.2022.11.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
5
|
Varga K, Sreter JA, Foxall TL. An insect antifreeze protein from Anatolica polita enhances the cryoprotection of mammalian cells. Cryobiology 2022. [DOI: 10.1016/j.cryobiol.2022.11.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
6
|
Ottlakán A, Paszt A, Simonka Z, Ábrahám S, Vass C, Varga K, Borda B, Vas M, Balogh Á, Lázár G. [Minimally invasive adrenalectomy – Operative and perioperative results of transperitoneal and retroperitoneal adrenalectomies performed at the University of Szeged Department of Surgery during 23 years]. Magy Seb 2022; 75:194-199. [PMID: 35895534 DOI: 10.1556/1046.2022.20016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 04/04/2022] [Indexed: 06/15/2023]
Abstract
Aim. Our goal was to evaluate operative and perioperative data of retroperitoneal (RP) and transperitoneal (TP) adrenalectomies performed at the University of Szeged Department of Surgery. Patients and method. During a retrospective cohort study including 174 adrenalectomies (28 RP; 146 TP) performed between 1998 and 2021, the following parameters were evaluated: rate of previous abdominal surgeries, conversion rate, operative time, intraoperative blood loss, tumor size, histology, hospital stay, early and late complications. Results. With significantly higher rate of previous abdominal surgeries [TP vs RP: 68 (46.57%) vs 4 (14%) P = 0.0021], there was no markable difference in conversion rate [TP vs RP: 7 (4.79%) vs 5 (18%), P = 0.312]. Significantly larger tumours were removed with TP (TP vs RP: 58.05 vs 34.8 mm, P = 0.016), with no markable difference in intraoperative blood loss (TP vs RP: 67.85 vs 50.2 ml, P = 0.157). Operative time was significantly shorter in TP (TP vs RP: 86.3 vs 134.5 min; P = 0.024). The most frequent histology was adenoma (TP vs RP: n = 95; 65.06% vs 64.3%). Pheochromocytoma occurred in 11 (7.53%) and 5 (17.8%) cases in TP and RP, respectively. We found no significant difference in hospital stay (TP vs RP: 5.125 vs 4.61 day; P = 0.413). Five- and 2 cases of early complications were seen in TP (splenic injury, postoperative fever, severe intraoperative bleeding, severe hypokalemia, surgical site infection) and RP (2 severe intraoperative bleeding), respectively. One lethal case of ventricular fibrillation and one delayed complication (postoperative abdominal wall hernia) were observed in TP. Conclusions. Both TP and RP are safe and simply reproducible minimally invasive techniques. According to our observation, RP adrenalectomy seems to be reserved for smaller lesions, while TP proves to be successful in removing enlarged and also malignant lesions with significantly shorter operative time.
Collapse
Affiliation(s)
- Aurél Ottlakán
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Attila Paszt
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Zsolt Simonka
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Szabolcs Ábrahám
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Csenge Vass
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Krisztina Varga
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Bernadett Borda
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Márton Vas
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - Ádám Balogh
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| | - György Lázár
- Szegedi Tudományegyetem Szent-Györgyi Albert Orvostudományi Kar, Sebészeti Klinika, Szeged, Magyarország (tanszékvezető: Prof. Dr. Lázár György)
| |
Collapse
|
7
|
Andrzejczyk J, Jovic K, Brown LM, Pascetta VG, Varga K, Vashisth H. Molecular interactions and inhibition of the SARS‐CoV‐2 main protease by a thiadiazolidinone derivative. Proteins 2022; 90:1896-1907. [PMID: 35567429 PMCID: PMC9347825 DOI: 10.1002/prot.26385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 04/17/2022] [Accepted: 05/10/2022] [Indexed: 11/15/2022]
Abstract
We report molecular interactions and inhibition of the main protease (MPro) of SARS‐CoV‐2, a key enzyme involved in the viral life cycle. By using a thiadiazolidinone (TDZD) derivative as a chemical probe, we explore the conformational dynamics of MPro via docking protocols and molecular dynamics simulations in all‐atom detail. We reveal the local and global dynamics of MPro in the presence of this inhibitor and confirm the inhibition of the enzyme with an IC50 value of 1.39 ± 0.22 μM, which is comparable to other known inhibitors of this enzyme.
Collapse
Affiliation(s)
- Jacob Andrzejczyk
- Department of Chemical Engineering University of New Hampshire Durham New Hampshire USA
| | - Katarina Jovic
- Department of Molecular, Cellular, and Biomedical Services University of New Hampshire Durham New Hampshire USA
| | - Logan M. Brown
- Department of Molecular, Cellular, and Biomedical Services University of New Hampshire Durham New Hampshire USA
| | - Valerie G. Pascetta
- Department of Molecular, Cellular, and Biomedical Services University of New Hampshire Durham New Hampshire USA
| | - Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Services University of New Hampshire Durham New Hampshire USA
| | - Harish Vashisth
- Department of Chemical Engineering University of New Hampshire Durham New Hampshire USA
| |
Collapse
|
8
|
Sreter JA, Foxall TL, Varga K. Intracellular and Extracellular Antifreeze Protein Significantly Improves Mammalian Cell Cryopreservation. Biomolecules 2022; 12:669. [PMID: 35625597 PMCID: PMC9139014 DOI: 10.3390/biom12050669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/23/2022] [Accepted: 04/29/2022] [Indexed: 12/03/2022] Open
Abstract
Cell cryopreservation is an essential part of the biotechnology, food, and health care industries. There is a need to develop more effective, less toxic cryoprotective agents (CPAs) and methods, especially for mammalian cells. We investigated the impact of an insect antifreeze protein from Anatolica polita (ApAFP752) on mammalian cell cryopreservation using the human embryonic kidney cell line HEK 293T. An enhanced green fluorescent protein (EGFP)-tagged antifreeze protein, EGFP-ApAFP752, was transfected into the cells and the GFP was used to determine the efficiency of transfection. AFP was assessed for its cryoprotective effects intra- and extracellularly and both simultaneously at different concentrations with and without dimethyl sulfoxide (DMSO) at different concentrations. Comparisons were made to DMSO or medium alone. Cells were cryopreserved at -196 °C for ≥4 weeks. Upon thawing, cellular viability was determined using trypan blue, cellular damage was assessed by lactate dehydrogenase (LDH) assay, and cellular metabolism was measured using a metabolic activity assay (MTS). The use of this AFP significantly improved cryopreserved cell survival when used with DMSO intracellularly. Extracellular AFP also significantly improved cell survival when included in the DMSO freezing medium. Intra- and extracellular AFP used together demonstrated the most significantly increased cryoprotection compared to DMSO alone. These findings present a potential method to improve the viability of cryopreserved mammalian cells.
Collapse
Affiliation(s)
- Jonathan A. Sreter
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA;
| | - Thomas L. Foxall
- Department of Biological Sciences, University of New Hampshire, Durham, NH 03824, USA;
| | - Krisztina Varga
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA;
| |
Collapse
|
9
|
Jevtić P, Elliott KW, Watkins SE, Sreter JA, Jovic K, Lehner IB, Baures PW, Tsavalas JG, Levy DL, Varga K. An insect antifreeze protein from Anatolica polita enhances the cryoprotection of Xenopus laevis eggs and embryos. J Exp Biol 2022; 225:jeb243662. [PMID: 35014670 PMCID: PMC8920033 DOI: 10.1242/jeb.243662] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 01/06/2022] [Indexed: 10/19/2022]
Abstract
Cryoprotection is of interest in many fields of research, necessitating a greater understanding of different cryoprotective agents. Antifreeze proteins have been identified that have the ability to confer cryoprotection in certain organisms. Antifreeze proteins are an evolutionary adaptation that contributes to the freeze resistance of certain fish, insects, bacteria and plants. These proteins adsorb to an ice crystal's surface and restrict its growth within a certain temperature range. We investigated the ability of an antifreeze protein from the desert beetle Anatolica polita, ApAFP752, to confer cryoprotection in the frog Xenopus laevis. Xenopus laevis eggs and embryos microinjected with ApAFP752 exhibited reduced damage and increased survival after a freeze-thaw cycle in a concentration-dependent manner. We also demonstrate that ApAFP752 localizes to the plasma membrane in eggs and embryonic blastomeres and is not toxic for early development. These studies show the potential of an insect antifreeze protein to confer cryoprotection in amphibian eggs and embryos.
Collapse
Affiliation(s)
- Predrag Jevtić
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
| | - K. Wade Elliott
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - Shelby E. Watkins
- Department of Chemistry, University of Wyoming, Laramie, WY 82071, USA
| | - Jonathan A. Sreter
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - Katarina Jovic
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - Ian B. Lehner
- Department of Chemistry, Keene State College, Keene, NH 03435, USA
| | - Paul W. Baures
- Department of Chemistry, Keene State College, Keene, NH 03435, USA
| | - John G. Tsavalas
- Department of Chemistry, University of New Hampshire, Durham, NH 03824, USA
| | - Daniel L. Levy
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
| | - Krisztina Varga
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA
| |
Collapse
|
10
|
Kwon YH, Tannir S, Balaz M, Varga K. Apple juice and red wine induced mirror-image circular dichroism in quantum dots. Chirality 2021; 34:70-76. [PMID: 34710252 DOI: 10.1002/chir.23380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/05/2021] [Accepted: 10/09/2021] [Indexed: 12/23/2022]
Abstract
Juices, wines, and extracts from plants contain high concentrations of various chiral compounds such as carboxylic acids or sugars. Several prior studies reported the synthesis of metallic and semiconducting nanoparticles relying on components of complex biological solutions. Herein, we present preparation of chiral CdS and CdSe quantum dots (QDs) using apple juice and red wine via phase transfer ligand exchange. Although both apple juice and red wine contain a complex mixture of chiral and achiral compounds, we have successfully used them for selective induction of predicted chiroptical properties and confirmed L-malic acid from the apple juice and L-tartaric acid from the red wine as the chiral inducers. This work illustrates the capability of using complex mixtures to construct chiral QDs with desired chiroptical properties as well as potential of QDs to selectively report a chiral molecule in a complex chiral mixture without the need for elaborate chiral recognition system.
Collapse
Affiliation(s)
- Yuri H Kwon
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Shambhavi Tannir
- Department of Chemistry, University of Wyoming, Laramie, WY, USA
| | - Milan Balaz
- Integrated Science and Engineering Division, Underwood International College, Yonsei University, Seoul, Republic of Korea
| | - Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| |
Collapse
|
11
|
Altincekic N, Korn SM, Qureshi NS, Dujardin M, Ninot-Pedrosa M, Abele R, Abi Saad MJ, Alfano C, Almeida FCL, Alshamleh I, de Amorim GC, Anderson TK, Anobom CD, Anorma C, Bains JK, Bax A, Blackledge M, Blechar J, Böckmann A, Brigandat L, Bula A, Bütikofer M, Camacho-Zarco AR, Carlomagno T, Caruso IP, Ceylan B, Chaikuad A, Chu F, Cole L, Crosby MG, de Jesus V, Dhamotharan K, Felli IC, Ferner J, Fleischmann Y, Fogeron ML, Fourkiotis NK, Fuks C, Fürtig B, Gallo A, Gande SL, Gerez JA, Ghosh D, Gomes-Neto F, Gorbatyuk O, Guseva S, Hacker C, Häfner S, Hao B, Hargittay B, Henzler-Wildman K, Hoch JC, Hohmann KF, Hutchison MT, Jaudzems K, Jović K, Kaderli J, Kalniņš G, Kaņepe I, Kirchdoerfer RN, Kirkpatrick J, Knapp S, Krishnathas R, Kutz F, zur Lage S, Lambertz R, Lang A, Laurents D, Lecoq L, Linhard V, Löhr F, Malki A, Bessa LM, Martin RW, Matzel T, Maurin D, McNutt SW, Mebus-Antunes NC, Meier BH, Meiser N, Mompeán M, Monaca E, Montserret R, Mariño Perez L, Moser C, Muhle-Goll C, Neves-Martins TC, Ni X, Norton-Baker B, Pierattelli R, Pontoriero L, Pustovalova Y, Ohlenschläger O, Orts J, Da Poian AT, Pyper DJ, Richter C, Riek R, Rienstra CM, Robertson A, Pinheiro AS, Sabbatella R, Salvi N, Saxena K, Schulte L, Schiavina M, Schwalbe H, Silber M, Almeida MDS, Sprague-Piercy MA, Spyroulias GA, Sreeramulu S, Tants JN, Tārs K, Torres F, Töws S, Treviño MÁ, Trucks S, Tsika AC, Varga K, Wang Y, Weber ME, Weigand JE, Wiedemann C, Wirmer-Bartoschek J, Wirtz Martin MA, Zehnder J, Hengesbach M, Schlundt A. Large-Scale Recombinant Production of the SARS-CoV-2 Proteome for High-Throughput and Structural Biology Applications. Front Mol Biosci 2021; 8:653148. [PMID: 34041264 PMCID: PMC8141814 DOI: 10.3389/fmolb.2021.653148] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/04/2021] [Indexed: 01/18/2023] Open
Abstract
The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential basis for further work, including macromolecular interaction studies and high-throughput drug screening. Here, we present the extensive catalog of a holistic SARS-CoV-2 protein preparation approach based on the consortium's collective efforts. We provide protocols for the large-scale production of more than 80% of all SARS-CoV-2 proteins or essential parts of them. Several of the proteins were produced in more than one laboratory, demonstrating the high interoperability between NMR groups worldwide. For the majority of proteins, we can produce isotope-labeled samples of HSQC-grade. Together with several NMR chemical shift assignments made publicly available on covid19-nmr.com, we here provide highly valuable resources for the production of SARS-CoV-2 proteins in isotope-labeled form.
Collapse
Affiliation(s)
- Nadide Altincekic
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Sophie Marianne Korn
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Nusrat Shahin Qureshi
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Marie Dujardin
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | - Martí Ninot-Pedrosa
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | - Rupert Abele
- Institute for Biochemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Marie Jose Abi Saad
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Caterina Alfano
- Structural Biology and Biophysics Unit, Fondazione Ri.MED, Palermo, Italy
| | - Fabio C. L. Almeida
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Islam Alshamleh
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Gisele Cardoso de Amorim
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Multidisciplinary Center for Research in Biology (NUMPEX), Campus Duque de Caxias Federal University of Rio de Janeiro, Duque de Caxias, Brazil
| | - Thomas K. Anderson
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI, United States
| | - Cristiane D. Anobom
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Chelsea Anorma
- Department of Chemistry, University of California, Irvine, CA, United States
| | - Jasleen Kaur Bains
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Adriaan Bax
- LCP, NIDDK, NIH, Bethesda, MD, United States
| | | | - Julius Blechar
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Anja Böckmann
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | - Louis Brigandat
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | - Anna Bula
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | - Matthias Bütikofer
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | | | - Teresa Carlomagno
- BMWZ and Institute of Organic Chemistry, Leibniz University Hannover, Hannover, Germany
- Group of NMR-Based Structural Chemistry, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Icaro Putinhon Caruso
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São José do Rio Preto, Brazil
| | - Betül Ceylan
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Apirat Chaikuad
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
- Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences, Frankfurt am Main, Germany
| | - Feixia Chu
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, United States
| | - Laura Cole
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | - Marquise G. Crosby
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States
| | - Vanessa de Jesus
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Karthikeyan Dhamotharan
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Isabella C. Felli
- Magnetic Resonance Centre (CERM), University of Florence, Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Sesto Fiorentino, Italy
| | - Jan Ferner
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Yanick Fleischmann
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Marie-Laure Fogeron
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | | | - Christin Fuks
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Boris Fürtig
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Angelo Gallo
- Department of Pharmacy, University of Patras, Patras, Greece
| | - Santosh L. Gande
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Juan Atilio Gerez
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Dhiman Ghosh
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Francisco Gomes-Neto
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratory of Toxinology, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Oksana Gorbatyuk
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States
| | | | | | - Sabine Häfner
- Leibniz Institute on Aging—Fritz Lipmann Institute (FLI), Jena, Germany
| | - Bing Hao
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States
| | - Bruno Hargittay
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - K. Henzler-Wildman
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI, United States
| | - Jeffrey C. Hoch
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States
| | - Katharina F. Hohmann
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Marie T. Hutchison
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | | | - Katarina Jović
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, United States
| | - Janina Kaderli
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Gints Kalniņš
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Iveta Kaņepe
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | - Robert N. Kirchdoerfer
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI, United States
| | - John Kirkpatrick
- BMWZ and Institute of Organic Chemistry, Leibniz University Hannover, Hannover, Germany
- Group of NMR-Based Structural Chemistry, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Stefan Knapp
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
- Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences, Frankfurt am Main, Germany
| | - Robin Krishnathas
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Felicitas Kutz
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Susanne zur Lage
- Group of NMR-Based Structural Chemistry, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Roderick Lambertz
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Andras Lang
- Leibniz Institute on Aging—Fritz Lipmann Institute (FLI), Jena, Germany
| | - Douglas Laurents
- “Rocasolano” Institute for Physical Chemistry (IQFR), Spanish National Research Council (CSIC), Madrid, Spain
| | - Lauriane Lecoq
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | - Verena Linhard
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Frank Löhr
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
- Institute of Biophysical Chemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Anas Malki
- Univ. Grenoble Alpes, CNRS, CEA, IBS, Grenoble, France
| | | | - Rachel W. Martin
- Department of Chemistry, University of California, Irvine, CA, United States
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States
| | - Tobias Matzel
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Damien Maurin
- Univ. Grenoble Alpes, CNRS, CEA, IBS, Grenoble, France
| | - Seth W. McNutt
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, United States
| | - Nathane Cunha Mebus-Antunes
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Beat H. Meier
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Nathalie Meiser
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Miguel Mompeán
- “Rocasolano” Institute for Physical Chemistry (IQFR), Spanish National Research Council (CSIC), Madrid, Spain
| | - Elisa Monaca
- Structural Biology and Biophysics Unit, Fondazione Ri.MED, Palermo, Italy
| | - Roland Montserret
- Molecular Microbiology and Structural Biochemistry, UMR 5086, CNRS/Lyon University, Lyon, France
| | | | - Celine Moser
- IBG-4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | | | - Thais Cristtina Neves-Martins
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Xiamonin Ni
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
- Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences, Frankfurt am Main, Germany
| | - Brenna Norton-Baker
- Department of Chemistry, University of California, Irvine, CA, United States
| | - Roberta Pierattelli
- Magnetic Resonance Centre (CERM), University of Florence, Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Sesto Fiorentino, Italy
| | - Letizia Pontoriero
- Magnetic Resonance Centre (CERM), University of Florence, Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Sesto Fiorentino, Italy
| | - Yulia Pustovalova
- Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, United States
| | | | - Julien Orts
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Andrea T. Da Poian
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Dennis J. Pyper
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Christian Richter
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Roland Riek
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Chad M. Rienstra
- Department of Biochemistry and National Magnetic Resonance Facility at Madison, University of Wisconsin-Madison, Madison, WI, United States
| | | | - Anderson S. Pinheiro
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Nicola Salvi
- Univ. Grenoble Alpes, CNRS, CEA, IBS, Grenoble, France
| | - Krishna Saxena
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Linda Schulte
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Marco Schiavina
- Magnetic Resonance Centre (CERM), University of Florence, Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Sesto Fiorentino, Italy
| | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Mara Silber
- IBG-4, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Marcius da Silva Almeida
- National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marc A. Sprague-Piercy
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States
| | | | - Sridhar Sreeramulu
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Jan-Niklas Tants
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Kaspars Tārs
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Felix Torres
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Sabrina Töws
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Miguel Á. Treviño
- “Rocasolano” Institute for Physical Chemistry (IQFR), Spanish National Research Council (CSIC), Madrid, Spain
| | - Sven Trucks
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
| | | | - Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, United States
| | - Ying Wang
- BMWZ and Institute of Organic Chemistry, Leibniz University Hannover, Hannover, Germany
| | - Marco E. Weber
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Julia E. Weigand
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Christoph Wiedemann
- Institute of Biochemistry and Biotechnology, Charles Tanford Protein Centre, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Julia Wirmer-Bartoschek
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Maria Alexandra Wirtz Martin
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Johannes Zehnder
- Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Martin Hengesbach
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Andreas Schlundt
- Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Frankfurt am Main, Germany
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| |
Collapse
|
12
|
Nordyke CT, Ahmed YM, Puterbaugh RZ, Bowman GR, Varga K. Intrinsically Disordered Bacterial Polar Organizing Protein Z, PopZ, Interacts with Protein Binding Partners Through an N-terminal Molecular Recognition Feature. J Mol Biol 2020; 432:6092-6107. [PMID: 33058876 DOI: 10.1016/j.jmb.2020.09.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/18/2020] [Accepted: 09/25/2020] [Indexed: 11/15/2022]
Abstract
The polar organizing protein Z (PopZ) is necessary for the formation of three-dimensional microdomains at the cell poles in Caulobacter crescentus, where it functions as a hub protein that recruits multiple regulatory proteins from the cytoplasm. Although a large portion of the protein is predicted to be natively unstructured, in reconstituted systems PopZ can self-assemble into a macromolecular scaffold that directly binds to at least ten different proteins. Here we report the solution NMR structure of PopZΔ134-177, a truncated form of PopZ that does not self-assemble but retains the ability to interact with heterologous proteins. We show that the unbound form of PopZΔ134-177 is unstructured in solution, with the exception of a small amphipathic α-helix in residues M10-I17, which is included within a highly conserved region near the N-terminal. In applying NMR techniques to map the interactions between PopZΔ134-177 and one of its binding partners, RcdA, we find evidence that the α-helix and adjoining amino acids extending to position E23 serve as the core of the binding motif. Consistent with this, a point mutation at position I17 severely compromises binding. Our results show that a partially structured Molecular Recognition Feature (MoRF) within an intrinsically disordered domain of PopZ contributes to the assembly of polar microdomains, revealing a structural basis for complex network assembly in Alphaproteobacteria that is analogous to those formed by intrinsically disordered hub proteins in other kingdoms.
Collapse
Affiliation(s)
- Christopher T Nordyke
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, United States
| | - Yasin M Ahmed
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, United States
| | - Ryan Z Puterbaugh
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, United States
| | - Grant R Bowman
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, United States.
| | - Krisztina Varga
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, United States.
| |
Collapse
|
13
|
Gupta R, Liu Y, Wang H, Nordyke CT, Puterbaugh RZ, Cui W, Varga K, Chu F, Ke H, Vashisth H, Cote RH. Structural Analysis of the Regulatory GAF Domains of cGMP Phosphodiesterase Elucidates the Allosteric Communication Pathway. J Mol Biol 2020; 432:5765-5783. [PMID: 32898583 PMCID: PMC7572642 DOI: 10.1016/j.jmb.2020.08.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 12/26/2022]
Abstract
Regulation of photoreceptor phosphodiesterase (PDE6) activity is responsible for the speed, sensitivity, and recovery of the photoresponse during visual signaling in vertebrate photoreceptor cells. It is hypothesized that physiological differences in the light responsiveness of rods and cones may result in part from differences in the structure and regulation of the distinct isoforms of rod and cone PDE6. Although rod and cone PDE6 catalytic subunits share a similar domain organization consisting of tandem GAF domains (GAFa and GAFb) and a catalytic domain, cone PDE6 is a homodimer whereas rod PDE6 consists of two homologous catalytic subunits. Here we provide the x-ray crystal structure of cone GAFab regulatory domain solved at 3.3 Å resolution, in conjunction with chemical cross-linking and mass spectrometric analysis of conformational changes to GAFab induced upon binding of cGMP and the PDE6 inhibitory γ-subunit (Pγ). Ligand-induced changes in cross-linked residues implicate multiple conformational changes in the GAFa and GAFb domains in forming an allosteric communication network. Molecular dynamics simulations of cone GAFab revealed differences in conformational dynamics of the two subunits forming the homodimer and allosteric perturbations on cGMP binding. Cross-linking of Pγ to GAFab in conjunction with solution NMR spectroscopy of isotopically labeled Pγ identified the central polycationic region of Pγ interacting with the GAFb domain. These results provide a mechanistic basis for developing allosteric activators of PDE6 with therapeutic implications for halting the progression of several retinal degenerative diseases.
Collapse
Affiliation(s)
- Richa Gupta
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH 03824, USA
| | - Yong Liu
- Department of Chemical Engineering, University of New Hampshire, 33 Academic Way, Durham, NH 03824, USA
| | - Huanchen Wang
- Signal Transduction Laboratory, NIEHS/NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Christopher T Nordyke
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH 03824, USA
| | - Ryan Z Puterbaugh
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH 03824, USA
| | - Wenjun Cui
- Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Krisztina Varga
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH 03824, USA
| | - Feixia Chu
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH 03824, USA
| | - Hengming Ke
- Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Harish Vashisth
- Department of Chemical Engineering, University of New Hampshire, 33 Academic Way, Durham, NH 03824, USA
| | - Rick H Cote
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH 03824, USA.
| |
Collapse
|
14
|
Yang H, Wu MS, Tang LY, Bromley MWJ, Varga K, Yan ZC, Zhang JY. Long-range interactions of the ground state muonium with atoms. J Chem Phys 2020; 152:124304. [PMID: 32241138 DOI: 10.1063/1.5144977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The scaling relations for the dispersion coefficients of long-range interactions between the Mu(1s)-Mu(1s, 2s, or 2p) systems and the H(1s)-H(1s, 2s, or 2p) systems are obtained using analytical properties of hydrogenic wavefunctions, which allows us to obtain the dispersion coefficients for Mu(1s)-Mu(1s, 2s, or 2p) systems from the corresponding H(1s)-H(1s, 2s, or 2p) systems. Additionally, the dispersion coefficients of long-range interactions of Mu(1s) with the ground-state H, noble gas atoms He, Ne, Ar, Kr, and Xe, alkali-metal atoms Li, Na, K, and Rb, alkaline-earth atoms Be, Mg, Ca, and Sr, and Cu, Ag, F, and Cl atoms are calculated.
Collapse
Affiliation(s)
- H Yang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - M-S Wu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - L-Y Tang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - M W J Bromley
- School of Mathematics and Physics, University of Queensland, Brisbane, Queensland 4075, Australia
| | - K Varga
- Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA
| | - Z-C Yan
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - J-Y Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| |
Collapse
|
15
|
Opšenák R, Fejerčák T, Hanko M, Snopko P, Varga K, Richterová R, Kolarovszki B. Is there an impact of subdural drainage duration and the number of burr holes on the recurrence rate of unilateral chronic subdural haematoma? Rozhl Chir 2020; 99:29-33. [PMID: 32122137 DOI: 10.33699/pis.2020.99.1.29-33] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
INTRODUCTION Purpose of the study is to evaluate a possible influence of subdural drainage duration and burr hole quantity on a relapse of a unilateral chronic subdural haematoma (CHSH). METHODS Sixty - five patients who underwent evacuation of unilateral CHSH via 1 or 2 burr holes and subdural drainage during a period from January 2014 to December 2018 were retrospectively analyzed. Duration of the subdural drainage and the number of burr holes used were assessed in relation to an incidence of CHSH recurrence. According to the subdural drainage duration, we divided the patient cohort into two subgroups: with the subdural drainage duration of 1-3 days and 4-5 days. We also evaluated a possible influence of the subdural drainage duration on risk of postoperative infection. RESULTS An overall incidence of CHSH recurrence was 18.5%. In 45 patients treated by means of a single burr hole the haematoma recurrence was observed in 10 patients (22.2%), in 22 patients with two burr holes recurrence occurred in 2 of them (9.1%). The difference was however, not statistically significant (p=0.3214). We did not observe any significant influence of age, gender and subdural drainage duration on the incidence of CHSH recurrence. The duration of subdural drainage had not significant impact on postoperative infection rate (p=0.0950). CONCLUSION The number of burr holes used does not affect the rate of unilateral CHSH recurrence. Similarly the duration of subdural drainage affects neither the unilateral CHSH recurrence rate nor the incidence of postoperative infection.
Collapse
|
16
|
Kratochvílová I, Kopečná O, Bačíková A, Pagáčová E, Falková I, Follett SE, Elliott KW, Varga K, Golan M, Falk M. Changes in Cryopreserved Cell Nuclei Serve as Indicators of Processes during Freezing and Thawing. Langmuir 2019; 35:7496-7508. [PMID: 30339402 DOI: 10.1021/acs.langmuir.8b02742] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The mechanisms underlying cell protection from cryoinjury are not yet fully understood. Recent biological studies have addressed cryopreserved cell survival but have not correlated the cryoprotection effectiveness with the impact of cryoprotectants on the most important cell structure, the nucleus, and the freeze/thaw process. We identified changes of cell nuclei states caused by different types of cryoprotectants and associate them with alterations of the freeze/thaw process in cells. Namely, we investigated both higher-order chromatin structure and nuclear envelope integrity as possible markers of freezing and thawing processes. Moreover, we analyzed in detail the relationship between nuclear envelope integrity, chromatin condensation, freeze/thaw processes in cells, and cryopreservation efficiency for dimethyl sulfoxide, glycerol, trehalose, and antifreeze protein. Our interdisciplinary study reveals how changes in cell nuclei induced by cryoprotectants affect the ability of cells to withstand freezing and thawing and how nuclei changes correlate with processes during freezing and thawing. Our results contribute to the deeper fundamental understanding of the freezing processes, notably in the cell nucleus, which will expand the applications and lead to the rational design of cryoprotective materials and protocols.
Collapse
Affiliation(s)
- Irena Kratochvílová
- Institute of Physics, v.v.i. , Czech Academy of Sciences , Na Slovance 2 , CZ-182 21 Prague 8 , Czech Republic
| | - Olga Kopečná
- Institute of Biophysics, v.v.i. , Czech Academy of Sciences , Královopolská 135 , CZ-612 65 Brno , Czech Republic
| | - Alena Bačíková
- Institute of Biophysics, v.v.i. , Czech Academy of Sciences , Královopolská 135 , CZ-612 65 Brno , Czech Republic
| | - Eva Pagáčová
- Institute of Biophysics, v.v.i. , Czech Academy of Sciences , Královopolská 135 , CZ-612 65 Brno , Czech Republic
| | - Iva Falková
- Institute of Biophysics, v.v.i. , Czech Academy of Sciences , Královopolská 135 , CZ-612 65 Brno , Czech Republic
| | - Shelby E Follett
- Department of Chemistry , University of Wyoming , 1000 E. University Avenue , Laramie , Wyoming 82071 , United States
| | - K Wade Elliott
- Department of Molecular, Cellular, and Biomedical Sciences , University of New Hampshire , 46 College Road , Durham , New Hampshire 03824 , United States
| | - Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences , University of New Hampshire , 46 College Road , Durham , New Hampshire 03824 , United States
| | - Martin Golan
- Institute of Physics, v.v.i. , Czech Academy of Sciences , Na Slovance 2 , CZ-182 21 Prague 8 , Czech Republic
| | - Martin Falk
- Institute of Biophysics, v.v.i. , Czech Academy of Sciences , Královopolská 135 , CZ-612 65 Brno , Czech Republic
| |
Collapse
|
17
|
Abstract
PURPOSE Cage subsidence (CS) represents a risk factor for adjacent segment degeneration (ASD) and unfavorable results of anterior cervical discectomy (ACD). METHODS Sixty-one patients after level 1 or 2 of ACD with implantation of Zero Profile VA cage were included in the study. CS was assessed with a follow-up period of 12 months after ACD. The impacts of factors such as sex, age, number of operated segments, osteoporosis and extent of peroperative distraction were assessed in relation to the incidence of CS. The influences of CS on clinical results (VAS, NDI, Odom's criteria) and ASD incidence were evaluated. RESULTS In 74 % of cases there was the presence of CS into both adjacent vertebral bodies. CS into the ventral part of motion segment was dominant during the entire follow-up period. CS had no influence on clinical results of ACD. Parallel CS into both ventral and dorsal parts of motion segments significantly increased the incidence of proximal ASD (p = 0.0163). Osteoporosis and extent of peroperative distraction were linked to higher incidence of CS into the dorsal part of motion segment (p ˂ 0.05). CONCLUSIONS Osteoporosis and the extent of peroperative distraction are risk factors for the subsidence of anchored cage and while increasing the incidence of proximal adjacent segment degeneration it has no significant influence on clinical results of surgery (Tab. 3, Fig. 5, Ref. 32).
Collapse
|
18
|
Opsenak R, Kolarovszki B, Benco M, Richterová R, Snopko P, Varga K, Hanko M. Dysphagia after anterior cervical discectomy and interbody fusion - prospective study with 1-year follow-up. Rozhl Chir 2019; 98:115-120. [PMID: 31018643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
INTRODUCTION Dysphagia is a common finding after anterior cervical discectomy. The incidence and severity of swallowing disorders are variable and depend on many factors. METHODS 73 patients after 1- or 2-level anterior cervical discectomy and fusion /ACDF/ were enrolled in prospective, single-center study. The severity of dysphagia was evaluated by the Bazaz-Yoo dysphagia score before surgery and 6 weeks, 3, 6 and 12 months after surgery. The impact of factors such as sex, age, number of operated segments, smoking, gastroesophageal reflux disease, hypertension, duration of surgery and pre-existing dysphagia on the incidence of dysphagia after surgery was verified. The correlation between the duration of surgery and severity of postoperative dysphagia, and similarly between the age and severity of preoperative and postoperative dysphagia was studied. RESULTS Dysphagia was present in 22% patients within 12 months after surgery. No patient reported severe dysphagia. No significant relationship was demonstrated between sex, age, number of operated segments, pre-existing dysphagia, gastroesophageal reflux disease, hypertension and the incidence of dysphagia after surgery. Smokers showed a significantly lower incidence of dysphagia before surgery and within 12 months after ACDF (p.
Collapse
|
19
|
Falk M, Falková I, Pagáčová E, Kopečná O, Bačíková A, Šimek D, Golan M, Klejdus B, Varga K, Teplá O, Kratochvílová I. Critical defects in cryopreserved cell nuclei: dna structure changes. Cryobiology 2018. [DOI: 10.1016/j.cryobiol.2018.10.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
20
|
Falk M, Falková I, Kopečná O, Bačíková A, Pagáčová E, Šimek D, Golan M, Kozubek S, Pekarová M, Follett SE, Klejdus B, Elliott KW, Varga K, Teplá O, Kratochvílová I. Chromatin architecture changes and DNA replication fork collapse are critical features in cryopreserved cells that are differentially controlled by cryoprotectants. Sci Rep 2018; 8:14694. [PMID: 30279538 PMCID: PMC6168476 DOI: 10.1038/s41598-018-32939-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 09/17/2018] [Indexed: 11/22/2022] Open
Abstract
In this work, we shed new light on the highly debated issue of chromatin fragmentation in cryopreserved cells. Moreover, for the first time, we describe replicating cell-specific DNA damage and higher-order chromatin alterations after freezing and thawing. We identified DNA structural changes associated with the freeze-thaw process and correlated them with the viability of frozen and thawed cells. We simultaneously evaluated DNA defects and the higher-order chromatin structure of frozen and thawed cells with and without cryoprotectant treatment. We found that in replicating (S phase) cells, DNA was preferentially damaged by replication fork collapse, potentially leading to DNA double strand breaks (DSBs), which represent an important source of both genome instability and defects in epigenome maintenance. This induction of DNA defects by the freeze-thaw process was not prevented by any cryoprotectant studied. Both in replicating and non-replicating cells, freezing and thawing altered the chromatin structure in a cryoprotectant-dependent manner. Interestingly, cells with condensed chromatin, which was strongly stimulated by dimethyl sulfoxide (DMSO) prior to freezing had the highest rate of survival after thawing. Our results will facilitate the design of compounds and procedures to decrease injury to cryopreserved cells.
Collapse
Affiliation(s)
- Martin Falk
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, CZ-612 65, Brno, Czech Republic.
| | - Iva Falková
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, CZ-612 65, Brno, Czech Republic
| | - Olga Kopečná
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, CZ-612 65, Brno, Czech Republic
| | - Alena Bačíková
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, CZ-612 65, Brno, Czech Republic
| | - Eva Pagáčová
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, CZ-612 65, Brno, Czech Republic
| | - Daniel Šimek
- The Czech Academy of Sciences, Institute of Physics, Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
| | - Martin Golan
- The Czech Academy of Sciences, Institute of Physics, Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
- Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, Prague 2, CZ-121 16, Czech Republic
| | - Stanislav Kozubek
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, CZ-612 65, Brno, Czech Republic
| | - Michaela Pekarová
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, CZ-612 65, Brno, Czech Republic
| | - Shelby E Follett
- Department of Chemistry, University of Wyoming, 1000 E. University Ave, WY 82071, Laramie, USA
| | - Bořivoj Klejdus
- Institute of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemědělská 1, CZ-613 00, Czech Republic
- CEITEC-Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-613 00, Brno, Czech Republic
| | - K Wade Elliott
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, 46 College Road, Durham, NH, 03824, USA
| | - Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, 46 College Road, Durham, NH, 03824, USA
| | - Olga Teplá
- ISCARE IVF a.s, Jankovcova 1692, CZ-160 00, Praha 6, Czech Republic
- VFN Gynekologicko-porodnická klinika, Apolinářská 18, CZ-120 00, Czech Republic
| | - Irena Kratochvílová
- The Czech Academy of Sciences, Institute of Physics, Na Slovance 2, CZ-182 21, Prague 8, Czech Republic.
| |
Collapse
|
21
|
Zsigmond AR, Varga K, Kántor I, Urák I, May Z, Héberger K. Elemental composition of wild growing Agaricus campestris mushroom in urban and peri-urban regions of Transylvania (Romania). J Food Compost Anal 2018. [DOI: 10.1016/j.jfca.2018.05.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|
22
|
Bánky B, Lakatos M, Varga K, Hansági E, Horváth É, Járay G. [Enhanced Recovery Program in colorectal surgery]. Magy Seb 2018. [PMID: 29536753 DOI: 10.1556/1046.71.2018.1.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Enhanced recovery after surgery (ERAS) programme has been described and practiced for twenty years in the perioperative management of colorectal patients. ERAS is a complex, evidence based strategy which proved to be extremely effective when linked to laparoscopy in reducing morbidity, length of hospital stay, as well as reducing cost of colorectal service. AIMS We gradually adapted elements of ERAS protocol along with laparoscopy in the colorectal surgical treatment at a county hospital from 2013. This study reports a retrospective clinical audit of ERAS programme of two years, between 2015-2016. METHODS In this timeframe we compared clinical results of traditional and ERAS perioperative colorectal management protocols. The two groups were assessed on the basis of demographic, cancer-related parameters and clinical outcomes. RESULTS Over the two years of audit we treated 130 patients under "traditional" and 84 cases according to ERAS protocol. Mean length of hospital stay was 8 and 6 days median, respectively. Earlier discharge in the ERAS group did not cause any increase in the readmission rates. Morbidity (Clavien-Dindo grade 2 or more) was found to be less in ERAS group: 8,3% vs. 27,4%. ERAS programme success rate, characterized by discharge by 7th postoperative day, was over 70%, keeping well with rates of the experienced centres of ERAS. CONCLUSION Therefore we can report a successful introduction of ERAS programme for colorectal service in a Middle-Eastern European county hospital. Based on the favourable outcome results of the retrospective audit we have extended ERAS protocol as first choice perioperative scheme for each elective colorectal case from the beginning of 2017.
Collapse
Affiliation(s)
- Balázs Bánky
- Sebészeti Osztály, Szent Borbála Kórház 2800 Tatabánya, Dózsa Gy. út 77
| | - Miklós Lakatos
- Sebészeti Osztály, Szent Borbála Kórház 2800 Tatabánya, Dózsa Gy. út 77
| | - Krisztina Varga
- Sebészeti Osztály, Szent Borbála Kórház 2800 Tatabánya, Dózsa Gy. út 77
| | - Edit Hansági
- Anaesthesiologiai és Intenzív Terápiás Osztály, Szent Borbála Kórház Tatabánya
| | - Éva Horváth
- Anaesthesiologiai és Intenzív Terápiás Osztály, Szent Borbála Kórház Tatabánya
| | - Géza Járay
- Sebészeti Osztály, Szent Borbála Kórház 2800 Tatabánya, Dózsa Gy. út 77
| |
Collapse
|
23
|
Varga K, Tannir S, Haynie BE, Leonard BM, Dzyuba SV, Kubelka J, Balaz M. CdSe Quantum Dots Functionalized with Chiral, Thiol-Free Carboxylic Acids: Unraveling Structural Requirements for Ligand-Induced Chirality. ACS Nano 2017; 11:9846-9853. [PMID: 28956912 DOI: 10.1021/acsnano.7b03555] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Functionalization of colloidal quantum dots (QDs) with chiral cysteine derivatives by phase-transfer ligand exchange proved to be a simple yet powerful method for the synthesis of chiral, optically active QDs regardless of their size and chemical composition. Here, we present induction of chirality in CdSe by thiol-free chiral carboxylic acid capping ligands (l- and d-malic and tartaric acids). Our circular dichroism (CD) and infrared experimental data showed how the presence of a chiral carboxylic acid capping ligand on the surface of CdSe QDs was necessary but not sufficient for the induction of optical activity in QDs. A chiral bis-carboxylic acid capping ligand needed to have three oxygen-donor groups during the phase-transfer ligand exchange to successfully induce chirality in CdSe. Intrinsic chirality of CdSe nanocrystals was not observed as evidenced by transmission electron microscopy and reverse phase-transfer ligand exchange with achiral 1-dodecanethiol. Density functional theory geometry optimizations and CD spectra simulations suggest an explanation for these observations. The tridentate binding via three oxygen-donor groups had an energetic preference for one of the two possible binding orientations on the QD (111) surface, leading to the CD signal. By contrast, bidentate binding was nearly equienergetic, leading to cancellation of approximately oppositely signed corresponding CD signals. The resulting induced CD of CdSe functionalized with chiral carboxylic acid capping ligands was the result of hybridization of the (achiral) QD and (chiral) ligand electronic states controlled by the ligand's absolute configuration and the ligand's geometrical arrangement on the QD surface.
Collapse
Affiliation(s)
- Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire , 46 College Road, Durham, New Hampshire 03824, United States
| | - Shambhavi Tannir
- Department of Chemistry, University of Wyoming , 1000 East University Avenue, Laramie, Wyoming 82071, United States
| | - Benjamin E Haynie
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire , 46 College Road, Durham, New Hampshire 03824, United States
| | - Brian M Leonard
- Department of Chemistry, University of Wyoming , 1000 East University Avenue, Laramie, Wyoming 82071, United States
| | - Sergei V Dzyuba
- Department of Chemistry and Biochemistry, Texas Christian University , Fort Worth, Texas 76129, United States
| | - Jan Kubelka
- Department of Chemistry, University of Wyoming , 1000 East University Avenue, Laramie, Wyoming 82071, United States
| | - Milan Balaz
- Underwood International College, Integrated Science and Engineering Division, Yonsei University , Seoul 03722, Republic of Korea
| |
Collapse
|
24
|
Hagemann N, Joseph S, Schmidt HP, Kammann CI, Harter J, Borch T, Young RB, Varga K, Taherymoosavi S, Elliott KW, McKenna A, Albu M, Mayrhofer C, Obst M, Conte P, Dieguez-Alonso A, Orsetti S, Subdiaga E, Behrens S, Kappler A. Organic coating on biochar explains its nutrient retention and stimulation of soil fertility. Nat Commun 2017; 8:1089. [PMID: 29057875 PMCID: PMC5715018 DOI: 10.1038/s41467-017-01123-0] [Citation(s) in RCA: 175] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 08/15/2017] [Indexed: 11/26/2022] Open
Abstract
Amending soil with biochar (pyrolized biomass) is suggested as a globally applicable approach to address climate change and soil degradation by carbon sequestration, reducing soil-borne greenhouse-gas emissions and increasing soil nutrient retention. Biochar was shown to promote plant growth, especially when combined with nutrient-rich organic matter, e.g., co-composted biochar. Plant growth promotion was explained by slow release of nutrients, although a mechanistic understanding of nutrient storage in biochar is missing. Here we identify a complex, nutrient-rich organic coating on co-composted biochar that covers the outer and inner (pore) surfaces of biochar particles using high-resolution spectro(micro)scopy and mass spectrometry. Fast field cycling nuclear magnetic resonance, electrochemical analysis and gas adsorption demonstrated that this coating adds hydrophilicity, redox-active moieties, and additional mesoporosity, which strengthens biochar-water interactions and thus enhances nutrient retention. This implies that the functioning of biochar in soil is determined by the formation of an organic coating, rather than biochar surface oxidation, as previously suggested. Biochar promotes plant growth via a slow release of nutrients; however, a mechanistic understanding of nutrient storage in biochar is lacking. Here, using high-resolution spectromicroscopy and mass spectrometry, the authors identify an organic coating on co-composted particles that enhances nutrient retention.
Collapse
Affiliation(s)
- Nikolas Hagemann
- Geomicrobiology, Center for Applied Geosciences, University of Tuebingen, Sigwartstrasse 10, Tuebingen, 72076, Germany.,Environmental Analytics, Agroscope, Reckenholzstraße 191, 8046, Zurich, Switzerland
| | - Stephen Joseph
- School of Environmental and Life Sciences, Chemistry, University of Newcastle, Callaghan, NSW 2308, Australia.,School of Materials Science and Engineering, University of New South Wales, Kensington, NSW 2052, Australia.,Nanjing Agricultural University, Nanjing, 210095, China
| | - Hans-Peter Schmidt
- Ithaka Institute for Carbon Strategies, Ancienne Eglise 9, Arbaz, 1974, Switzerland
| | - Claudia I Kammann
- Department of Soil Science and Plant Nutrition, WG Climate Change Research for Special Crops, Hochschule Geisenheim University, von-Lade Str. 1, Geisenheim, 65366, Germany
| | - Johannes Harter
- Geomicrobiology, Center for Applied Geosciences, University of Tuebingen, Sigwartstrasse 10, Tuebingen, 72076, Germany
| | - Thomas Borch
- Department of Soil and Crop Sciences and Department of Chemistry, Colorado State University, Fort Collins, CO, 80523, USA
| | - Robert B Young
- Department of Soil and Crop Sciences and Department of Chemistry, Colorado State University, Fort Collins, CO, 80523, USA
| | - Krisztina Varga
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, 03824, USA
| | - Sarasadat Taherymoosavi
- School of Environmental and Life Sciences, Chemistry, University of Newcastle, Callaghan, NSW 2308, Australia
| | - K Wade Elliott
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, 03824, USA
| | - Amy McKenna
- National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL, 32310-4005, USA
| | - Mihaela Albu
- Austrian Cooperative Research, Centre for Electron Microscopy and Nanoanalysis, Steyrergasse 17, Graz, 8010, Austria
| | - Claudia Mayrhofer
- Austrian Cooperative Research, Centre for Electron Microscopy and Nanoanalysis, Steyrergasse 17, Graz, 8010, Austria
| | - Martin Obst
- BayCEER Analytics, University of Bayreuth, Bayreuth, 95440, Germany
| | - Pellegrino Conte
- Dipartimento di Scienze Agrarie e Forestali, Università degli Studi di Palermo, v.le delle Scienze ed. 4, Palermo, 90128, Italy
| | - Alba Dieguez-Alonso
- Institute of Energy Engineering, Chair for Energy Process Engineering and Conversion Technologies for Renewable Energies, Technische Universität Berlin, Fasanenstraße 89, Berlin, 10623, Germany
| | - Silvia Orsetti
- Environmental Mineralogy and Chemistry, Center for Applied Geoscience, University of Tuebingen, Sigwartstrasse 10, Tuebingen, 72076, Germany
| | - Edisson Subdiaga
- Environmental Mineralogy and Chemistry, Center for Applied Geoscience, University of Tuebingen, Sigwartstrasse 10, Tuebingen, 72076, Germany
| | - Sebastian Behrens
- Department for Civil, Environmental, and Geo-Engineering, University of Minnesota, 500 Pillsbury Drive S.E, Minneapolis, MN, 55455-0116, USA.,BioTechonology Institute, 140 Gortner Labs, 1479 Gortner Avenue, St. Paul, MN, 55108-6106, USA
| | - Andreas Kappler
- Geomicrobiology, Center for Applied Geosciences, University of Tuebingen, Sigwartstrasse 10, Tuebingen, 72076, Germany.
| |
Collapse
|
25
|
Wieckowski A, Zelenay P, Varga K. A comprehensive study of bisulfate adsorption on Pt(111) by radioactive labeling and voltammetry. ACTA ACUST UNITED AC 2017. [DOI: 10.1051/jcp/1991881247] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
26
|
Kratochvílová I, Golan M, Pomeisl K, Richter J, Sedláková S, Šebera J, Mičová J, Falk M, Falková I, Řeha D, Elliott KW, Varga K, Follett SE, Šimek D. Theoretical and experimental study of the antifreeze protein AFP752, trehalose and dimethyl sulfoxide cryoprotection mechanism: correlation with cryopreserved cell viability. RSC Adv 2016; 7:352-360. [PMID: 28936355 DOI: 10.1039/c6ra25095e] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this work the physico-chemical properties of selected cryoprotectants (antifreeze protein TrxA-AFP752, trehalose and dimethyl sulfoxide) were correlated with their impact on the constitution of ice and influence on frozen/thawed cell viability. The freezing processes and states of investigated materials solutions were described and explained from a fundamental point of view using ab-initio modelling (molecular dynamics, DFT), Raman spectroscopy, Differential Scanning Calorimetry and X-Ray Diffraction. For the first time, in this work we correlated the microscopic view (modelling) with the description of the frozen solution states and put these results in the context of human skin fibroblast viability after freezing and thawing. DMSO and AFP had different impacts on their solution's freezing process but in both cases the ice crystallinity size was considerably reduced. DMSO and AFP treatment in different ways improved the viability of frozen/thawed cells.
Collapse
Affiliation(s)
- Irena Kratochvílová
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
| | - Martin Golan
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic.,Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, CZ-121 16 Prague 2, Czech Republic
| | - Karel Pomeisl
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
| | - Jan Richter
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
| | - Silvia Sedláková
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
| | - Jakub Šebera
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
| | - Júlia Mičová
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic.,Institute of Chemistry, Slovak Academy of Sciences, Dubravska cesta 9,845 38 Bratislava 4, Slovak Republic
| | - Martin Falk
- Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 65 Brno, Czech Republic
| | - Iva Falková
- Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 65 Brno, Czech Republic
| | - David Řeha
- Institute of Microbiology, Academy of Sciences of the Czech Republic, v.v.i., Zámek 136, CZ-373 33 Nové Hrady, Czech Republic.,Faculty of Sciences, University of South Bohemia in Ceske Budejovice, Zamek 136, 373 33 Nove Hrady, Czech Republic
| | - K Wade Elliott
- Deparment of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, 46 College Road, Durham, NH, 03824, USA
| | - Krisztina Varga
- Deparment of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, 46 College Road, Durham, NH, 03824, USA
| | - Shelby E Follett
- Department of Chemistry, University of Wyoming, 1000 E. University Ave, Laramie, WY, 82071, USA
| | - Daniel Šimek
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-182 21, Prague 8, Czech Republic
| |
Collapse
|
27
|
Warner L, Gjersing E, Follett SE, Elliott KW, Dzyuba SV, Varga K. The effects of high concentrations of ionic liquid on GB1 protein structure and dynamics probed by high-resolution magic-angle-spinning NMR spectroscopy. Biochem Biophys Rep 2016; 8:75-80. [PMID: 28717785 PMCID: PMC5510950 DOI: 10.1016/j.bbrep.2016.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Ionic liquids have great potential in biological applications and biocatalysis, as some ionic liquids can stabilize proteins and enhance enzyme activity, while others have the opposite effect. However, on the molecular level, probing ionic liquid interactions with proteins, especially in solutions containing high concentrations of ionic liquids, has been challenging. In the present work the 13C, 15N-enriched GB1 model protein was used to demonstrate applicability of high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy to investigate ionic liquid–protein interactions. Effect of an ionic liquid (1-butyl-3-methylimidazolium bromide, [C4-mim]Br) on GB1was studied over a wide range of the ionic liquid concentrations (0.6–3.5 M, which corresponds to 10–60% v/v). Interactions between GB1 and [C4-mim]Br were observed from changes in the chemical shifts of the protein backbone as well as the changes in 15N ps-ns dynamics and rotational correlation times. Site-specific interactions between the protein and [C4-mim]Br were assigned using 3D methods under HR-MAS conditions. Thus, HR-MAS NMR is a viable tool that could aid in elucidation of molecular mechanisms of ionic liquid–protein interactions. Probing IL interactions with proteins using conventional techniques is challenging. Here, HR-MAS NMR was used to investigate IL–protein interactions. Model protein GB1 was investigated in high concentrations of [C4-mim]Br. This technique facilitates atomic level characterization of protein-IL interactions.
Collapse
Affiliation(s)
- Lisa Warner
- National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Erica Gjersing
- National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Shelby E Follett
- Department of Chemistry, University of Wyoming, Laramie, WY, 82071, USA
| | - K Wade Elliott
- Department of Chemistry, University of Wyoming, Laramie, WY, 82071, USA
| | - Sergei V Dzyuba
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, TX, 76129 USA
| | - Krisztina Varga
- Department of Chemistry, University of Wyoming, Laramie, WY, 82071, USA
| |
Collapse
|
28
|
Choi JK, Haynie BE, Tohgha U, Pap L, Elliott KW, Leonard BM, Dzyuba SV, Varga K, Kubelka J, Balaz M. Chirality Inversion of CdSe and CdS Quantum Dots without Changing the Stereochemistry of the Capping Ligand. ACS Nano 2016; 10:3809-3815. [PMID: 26938741 DOI: 10.1021/acsnano.6b00567] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
L-cysteine derivatives induce and modulate the optical activity of achiral cadmium selenide (CdSe) and cadmium sulfide (CdS) quantum dots (QDs). Remarkably, N-acetyl-L-cysteine-CdSe and L-homocysteine-CdSe as well as N-acetyl-L-cysteine-CdS and L-cysteine-CdS showed "mirror-image" circular dichroism (CD) spectra regardless of the diameter of the QDs. This is an example of the inversion of the CD signal of QDs by alteration of the ligand's structure, rather than inversion of the ligand's absolute configuration. Non-empirical quantum chemical simulations of the CD spectra were able to reproduce the experimentally observed sign patterns and demonstrate that the inversion of chirality originated from different binding arrangements of N-acetyl-L-cysteine and L-homocysteine-CdSe to the QD surface. These efforts may allow the prediction of the ligand-induced chiroptical activity of QDs by calculating the specific binding modes of the chiral capping ligands. Combined with the large pool of available chiral ligands, our work opens a robust approach to the rational design of chiral semiconducting nanomaterials.
Collapse
Affiliation(s)
- Jung Kyu Choi
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Benjamin E Haynie
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Urice Tohgha
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Levente Pap
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - K Wade Elliott
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Brian M Leonard
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Sergei V Dzyuba
- Department of Chemistry and Biochemistry, Texas Christian University , Fort Worth, Texas 76129, United States
| | - Krisztina Varga
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Jan Kubelka
- Department of Chemistry, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Milan Balaz
- Underwood International College, Integrated Science & Engineering Division, Yonsei University , Seoul 03722, Republic of Korea
| |
Collapse
|
29
|
Golan M, Sedláková S, Mičová J, Šebera J, Kratochvílová I, Richter J, Řeha D, Falk M, Falková I, Bačíková A, Pagáčová E, Varga K. Freezing processes in cryoprotective solutions of Me2SO, trehalose and antifreeze protein ApAFP752 and their impact on chromatin condition of cryopreserved cells. Cryobiology 2015. [DOI: 10.1016/j.cryobiol.2015.10.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
30
|
Dannatt HRW, Taylor GF, Varga K, Higman VA, Pfeil MP, Asilmovska L, Judge PJ, Watts A. ¹³C- and ¹H-detection under fast MAS for the study of poorly available proteins: application to sub-milligram quantities of a 7 trans-membrane protein. J Biomol NMR 2015; 62:17-23. [PMID: 25701262 DOI: 10.1007/s10858-015-9911-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 02/14/2015] [Indexed: 06/04/2023]
Abstract
We demonstrate that (13)C-detected spectra recorded using fast (60 kHz) magic angle spinning on sub-milligram (<10 μmol) quantities of a protonated 7 trans-membrane helix protein (bacteriorhodopsin) in its native lipid environment are comparable in sensitivity and resolution to those recorded using 15-fold larger sample volumes with conventional solid state NMR methodology. We demonstrate the utility of proton-detected measurements which yield narrow (1)H linewidths under these conditions, and that no structural alterations are observed. We propose that these methods will prove useful to gain structural information on membrane proteins with poor availability, which can be studied in their native lipid environments.
Collapse
Affiliation(s)
- Hugh R W Dannatt
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Tohgha U, Deol KK, Porter AG, Bartko SG, Choi JK, Leonard BM, Varga K, Kubelka J, Muller G, Balaz M. Ligand induced circular dichroism and circularly polarized luminescence in CdSe quantum dots. ACS Nano 2013; 7:11094-102. [PMID: 24200288 PMCID: PMC3927652 DOI: 10.1021/nn404832f] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Chiral thiol capping ligands L- and D-cysteines induced modular chiroptical properties in achiral cadmium selenide quantum dots (CdSe QDs). Cys-CdSe prepared from achiral oleic acid capped CdSe by postsynthetic ligand exchange displayed size-dependent electronic circular dichroism (CD) and circularly polarized luminescence (CPL). Opposite CPL signals were measured for the CdSe QDs capped with D- and L-cysteine. The CD profile and CD anisotropy varied with size of CdSe nanocrystals with largest anisotropy observed for CdSe nanoparticles of 4.4 nm. Magic angle spinning solid state NMR (MAS ssNMR) experiments suggested bidentate interaction between cysteine and the surface of CdSe. Time Dependent Density Functional Theory (TDDFT) calculations verified that attachment of L- and D-cysteine to the surface of model (CdSe)13 nanoclusters induces measurable opposite CD signals for the exitonic band of the nanocluster. The origin of the induced chirality is consistent with the hybridization of highest occupied CdSe molecular orbitals with those of the chiral ligand.
Collapse
Affiliation(s)
- Urice Tohgha
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
| | - Kirandeep K. Deol
- Department of Chemistry, San José State University, San José, CA 95192-0101, USA
| | - Ashlin G. Porter
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
| | - Samuel G. Bartko
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
| | - Jung Kyu Choi
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
| | - Brian M. Leonard
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
| | - Krisztina Varga
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
| | - Jan Kubelka
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
| | - Gilles Muller
- Department of Chemistry, San José State University, San José, CA 95192-0101, USA
- Gilles Muller, Department of Chemistry, San José State University, San José, CA 95192-0101, USA. Fax: +1 408 924-4945; Tel: +1 408 924-5000;
| | - Milan Balaz
- University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA
- Corresponding Authors Milan Balaz, University of Wyoming, Department of Chemistry, 1000 E. University Ave, Laramie, USA. Fax: +1 307 766-2807; Tel: +1 307 766-4330;
| |
Collapse
|
32
|
Tohgha U, Varga K, Balaz M. Achiral CdSe quantum dots exhibit optical activity in the visible region upon post-synthetic ligand exchange with d- or l-cysteine. Chem Commun (Camb) 2013; 49:1844-6. [DOI: 10.1039/c3cc37987f] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
33
|
Xie X, Roither S, Schöffler M, Kartashov D, Xu H, Zhang L, Rathje T, Paulus GG, Doblhoff-Dier K, Gräfe S, Bubin S, Atkinson M, Varga K, Yamanouchi K, Baltuška A, Kitzler M. Fragmentation Control of a Polyatomic Molecule by fully determined Laser-Fields. EPJ Web of Conferences 2013. [DOI: 10.1051/epjconf/20134102021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
34
|
Roither S, Xie X, Schöffer M, Kartashov D, Zhang L, Iwasaki A, Xu H, Bubin S, Atkinson M, Varga K, Yamanouchi K, Baltuška A, Kitzler M. Highly Efficient Molecular Ionization Probed by Few-cycle Laser Pulses. EPJ Web of Conferences 2013. [DOI: 10.1051/epjconf/20134102005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
35
|
Abstract
The projection method is used to demonstrate the existence of positron attachment to three doubly excited states of helium. The e(+)He(2s(2) (1)S(e))deg, e(+)He(3s(2) (1)S(e)), and the e(+)He(2s2p (3)P(o)) states have binding energies of 0.447, 0.256, and 0.486 eV, respectively. These energies were computed with the stochastic variational method and the configuration interaction method. These states will exist as resonances in the e(+)-He continuum, and the e(+)He(2s(2) (1)S(e)) state could be detectable in the e(+)+He collision spectrum. A resonance width of 0.068 eV was computed for the e(+)He(2s(2) (1)S(e)) state by using the complex rotation method. The existence of a series of e(+)He(ns(2) (1)S(e)) resonances associated with the He(ns(2)) double Rydberg series is also predicted, and an explicit calculation demonstrating the existence of the e(+)He(3s(2) (1)S(e)) state is reported.
Collapse
Affiliation(s)
- M W J Bromley
- Centre for Quantum-Atom Optics, School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland 4075, Australia
| | | | | |
Collapse
|
36
|
Abstract
Cell invasion from an aggregate into a surrounding extracellular matrix (ECM) is an important process during development disease, e.g., vascular network assembly or tumor progression. To describe the behavior emerging from autonomous cell motility, cell-cell adhesion and contact guidance by ECM filaments, we propose a suitably modified cellular Potts model. We consider an active cell motility process in which internal polarity is governed by a positive feedback from cell displacements, a mechanism that can result in highly persistent motion when constrained by an oriented ECM structure. The model allows us to explore the interplay between haptotaxis, matrix degradation and active cell movement. We show that for certain conditions the cells are able to both invade the ECM and follow the ECM tracks. Furthermore, we argue that enforcing mechanical equilibrium within a bulk cell mass is of key importance in multicellular simulations.
Collapse
Affiliation(s)
- A Szabó
- Department of Biological Physics, Eotvos University, Budapest, Hungary
| | | | | | | | | |
Collapse
|
37
|
Higman VA, Varga K, Aslimovska L, Judge PJ, Sperling LJ, Rienstra CM, Watts A. Ermittlung der Konformation von Bacteriorhodopsin-Peptidschleifen in Purpurmembranen durch Festkörper-MAS-NMR-Spektroskopie. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201100730] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
38
|
Higman VA, Varga K, Aslimovska L, Judge PJ, Sperling LJ, Rienstra CM, Watts A. The conformation of bacteriorhodopsin loops in purple membranes resolved by solid-state MAS NMR spectroscopy. Angew Chem Int Ed Engl 2011; 50:8432-5. [PMID: 21770003 DOI: 10.1002/anie.201100730] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 04/27/2011] [Indexed: 01/26/2023]
Affiliation(s)
- Victoria A Higman
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | | | | | | | | | | | | |
Collapse
|
39
|
Warner LR, Varga K, Lange OF, Baker SL, Baker D, Sousa MC, Pardi A. Structure of the BamC two-domain protein obtained by Rosetta with a limited NMR data set. J Mol Biol 2011; 411:83-95. [PMID: 21624375 DOI: 10.1016/j.jmb.2011.05.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2011] [Revised: 05/13/2011] [Accepted: 05/16/2011] [Indexed: 10/18/2022]
Abstract
The CS-RDC-NOE Rosetta program was used to generate the solution structure of a 27-kDa fragment of the Escherichia coli BamC protein from a limited set of NMR data. The BamC protein is a component of the essential five-protein β-barrel assembly machine in E. coli. The first 100 residues in BamC were disordered in solution. The Rosetta calculations showed that BamC₁₀₁₋₃₄₄ forms two well-defined domains connected by an ~18-residue linker, where the relative orientation of the domains was not defined. Both domains adopt a helix-grip fold previously observed in the Bet v 1 superfamily. ¹⁵N relaxation data indicated a high degree of conformational flexibility for the linker connecting the N-terminal domain and the C-terminal domain in BamC. The results here show that CS-RDC-NOE Rosetta is robust and has a high tolerance for misassigned nuclear Overhauser effect restraints, greatly simplifying NMR structure determinations.
Collapse
Affiliation(s)
- Lisa R Warner
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Boulder, CO 80309, USA
| | | | | | | | | | | | | |
Collapse
|
40
|
Kádár P, Varga K, Baja B, Németh Z, Vajda N, Stefánka Z, Kövér L, Cserny I, Tóth J, Pintér T, Schunk J. Accumulation of uranium, transuranium and fission products on stainless steel surfaces II. Sorption studies in a laboratory model system. J Radioanal Nucl Chem 2011. [DOI: 10.1007/s10967-011-1038-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
41
|
|
42
|
Rowe SM, Pyle LC, Jurkevante A, Varga K, Collawn J, Sloane PA, Woodworth B, Mazur M, Fulton J, Fan L, Li Y, Fortenberry J, Sorscher EJ, Clancy JP. DeltaF508 CFTR processing correction and activity in polarized airway and non-airway cell monolayers. Pulm Pharmacol Ther 2010; 23:268-78. [PMID: 20226262 DOI: 10.1016/j.pupt.2010.02.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 02/13/2010] [Accepted: 02/17/2010] [Indexed: 12/21/2022]
Abstract
We examined the activity of DeltaF508 cystic fibrosis transmembrane conductance regulator (CFTR) stably expressed in polarized cystic fibrosis bronchial epithelial cells (CFBE41o(-)) human airway cells and Fisher Rat Thyroid (FRT) cells following treatment with low temperature and a panel of small molecule correctors of DeltaF508 CFTR misprocessing. Corr-4a increased DeltaF508 CFTR-dependent Cl(-) conductance in both cell types, whereas treatment with VRT-325 or VRT-640 increased activity only in FRT cells. Total currents stimulated by forskolin and genistein demonstrated similar dose/response effects to Corr-4a treatment in each cell type. When examining the relative contribution of forskolin and genistein to total stimulated current, CFBE41o(-) cells had smaller forskolin-stimulated I(sc) following either low temperature or corr-4a treatment (10-30% of the total I(sc) produced by the combination of both CFTR agonists). In contrast, forskolin consistently contributed greater than 40% of total I(sc) in DeltaF508 CFTR-expressing FRT cells corrected with low temperature, and corr-4a treatment preferentially enhanced forskolin dependent currents only in FRT cells (60% of total I(sc)). DeltaF508 CFTR cDNA transcript levels, DeltaF508 CFTR C band levels, or cAMP signaling did not account for the reduced forskolin response in CFBE41o(-) cells. Treatment with non-specific inhibitors of phosphodiesterases (papaverine) or phosphatases (endothall) did not restore DeltaF508 CFTR activation by forskolin in CFBE41o(-) cells, indicating that the Cl(-) transport defect in airway cells is distal to cAMP or its metabolism. The results identify important differences in DeltaF508 CFTR activation in polarizing epithelial models of CF, and have important implications regarding detection of rescued of DeltaF508 CFTR in vivo.
Collapse
Affiliation(s)
- S M Rowe
- Department of Medicine, University of Alabama at Birmingham, 1530 3rd Ave. South, Birmingham, AL 35294-0005, United States.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Varga K, Frick JE, Kapa LL, Dengler MJ. Developmental changes in inhibition of return from 3 to 6 months of age. Infant Behav Dev 2010; 33:245-9. [PMID: 20117841 DOI: 10.1016/j.infbeh.2009.12.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 09/29/2009] [Accepted: 12/30/2009] [Indexed: 11/24/2022]
Abstract
The development of inhibition of return was examined in 3-6-month-olds using varied stimulus onset asynchronies. The 300 ms SOA condition revealed particularly interesting findings as it elicited facilitation in 4.5-month-olds, but inhibition in 6-month-olds. Implications for understanding the development of IOR are discussed.
Collapse
Affiliation(s)
- Krisztina Varga
- James Madison University, Department of Psychology, MSC 7704, Harrisonburg, VA, United States.
| | | | | | | |
Collapse
|
44
|
Zhang JY, Mitroy J, Varga K. Positron scattering and annihilation from the hydrogen molecule at zero energy. Phys Rev Lett 2009; 103:223202. [PMID: 20366093 DOI: 10.1103/physrevlett.103.223202] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Indexed: 05/29/2023]
Abstract
The confined variational method is used to generate a basis of correlated Gaussians to describe the interaction region wave function for positron scattering from the H2 molecule. The scattering length was approximately = -2.7a(0) while the zero energy Z(eff) of 15.7 is compatible with experimental values. The variation of the scattering length and Z(eff) with internuclear distance was surprisingly rapid due to virtual state formation at R approximately = 3.4a(0).
Collapse
Affiliation(s)
- J-Y Zhang
- ARC Center for Anti-Matter Studies, School of Engineering, Charles Darwin University, Darwin NT 0909, Australia
| | | | | |
Collapse
|
45
|
Mitroy J, Zhang JY, Varga K. Elastic scattering using an artificial confining potential. Phys Rev Lett 2008; 101:123201. [PMID: 18851369 DOI: 10.1103/physrevlett.101.123201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Revised: 07/14/2008] [Indexed: 05/26/2023]
Abstract
The discrete energies of a scattering Hamiltonian calculated under the influence of an artificial confining potential of almost arbitrary functional form can be used to determine its phase shifts. The method exploits the result that two short-range Hamiltonians having the same energy will have the same phase shifts upon removal of the confining potential. An initial verification is performed on a simple model problem. Then the stochastic variational method is used to determine the energies of the confined e(-)-He(2)S(e) system and thus determine the low energy phase shifts.
Collapse
Affiliation(s)
- J Mitroy
- ARC Center for Anti-Matter Studies, Faculty of Technology, Charles Darwin University, Darwin NT 0909, Australia
| | | | | |
Collapse
|
46
|
Varga K, Aslimovska L, Watts A. Advances towards resonance assignments for uniformly--13C, 15N enriched bacteriorhodopsin at 18.8 T in purple membranes. J Biomol NMR 2008; 41:1-4. [PMID: 18427930 DOI: 10.1007/s10858-008-9235-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 03/25/2008] [Accepted: 03/27/2008] [Indexed: 05/26/2023]
Abstract
Solid state NMR spectra from uniformly (13)C, (15)N enriched bacteriorhodospin (bR) purified from H. salinarium were acquired at 18.8 T using magic angle spinning methods. Isolated resonances of 2D (13)C-(13)C spectra exhibited 0.50-0.55 ppm line-widths. Several amino acid types could be assigned, and at least 12 out of 15 Ile peaks could be resolved clearly and identified based on their characteristic chemical shifts and connectivities. This study confirms that high resolution solid state NMR spectra can be obtained for a 248 amino acid uniformly labeled membrane protein in its native membrane environment and indicates that site-specific assignments are likely to be feasible with heteronuclear multidimensional spectra.
Collapse
Affiliation(s)
- Krisztina Varga
- Biomembrane Structure Unit, Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, UK
| | | | | |
Collapse
|
47
|
Varga K, Aslimovska L, Parrot I, Dauvergne MT, Haertlein M, Forsyth VT, Watts A. NMR crystallography: the effect of deuteration on high resolution 13C solid state NMR spectra of a 7-TM protein. Biochim Biophys Acta 2007; 1768:3029-35. [PMID: 18001693 DOI: 10.1016/j.bbamem.2007.09.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 09/24/2007] [Accepted: 09/27/2007] [Indexed: 11/24/2022]
Abstract
The effect of deuteration on the 13C linewidths of U-13C, 15N 2D crystalline bacteriorhodopsin (bR) from Halobacterium salinarium, a 248-amino acid protein with seven-transmembrane (7TM) spanning regions, has been studied in purple membranes as a prelude to potential structural studies. Spectral doubling of resonances was observed for receptor expressed in 2H medium (for both 50:50% 1H:2H, and a more highly deuterated form) with the resonances being of similar intensities and separated by <0.3 ppm in the methyl spectral regions in which they were readily distinguished. Line-widths of the methyl side chains were not significantly altered when the protein was expressed in highly deuterated medium compared to growth in fully protonated medium (spectral line widths were about 0.5 ppm on average for receptor expressed both in the fully protonated and highly deuterated media from the C delta, C gamma 1, and C gamma 2 Ile 13C signals observed in the direct, 21-39 ppm, and indirect, 9-17 ppm, dimensions). The measured 13C NMR line-widths observed for both protonated and deuterated form of the receptor are sufficiently narrow, indicating that this crystalline protein morphology is suitable for structural studies. 1) decoupling comparison of the protonated and deuterated bR imply that deuteration may be advantageous for samples in which low power 1H decoupling is required.
Collapse
Affiliation(s)
- K Varga
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
| | | | | | | | | | | | | |
Collapse
|
48
|
Varga K, Tian L, McDermott AE. Solid-state NMR study and assignments of the KcsA potassium ion channel of S. lividans. Biochim Biophys Acta 2007; 1774:1604-13. [PMID: 17974509 DOI: 10.1016/j.bbapap.2007.08.029] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 08/15/2007] [Accepted: 08/29/2007] [Indexed: 10/22/2022]
Abstract
The extraordinary efficiency and selectivity of potassium channels have made them ideal systems for biophysical and functional studies of ion conduction. We carried out solid-state NMR studies of the selectivity filter region of the protein. Partial site-specific assignments of the NMR signals were obtained based on high field multidimensional solid-state NMR spectra of uniformly (13)C, (15)N enriched KcsA potassium channel from Streptomyces lividans. Both backbone and sidechain atoms were assigned for residues V76-D80 and P83-L90, in and near the selectivity filter region of the protein; this region exhibits good dispersion and useful chemical shift fingerprints. This study will enable structure, dynamic and mechanistic studies of ion conduction by NMR.
Collapse
Affiliation(s)
- Krisztina Varga
- Department of Chemistry, Columbia University, 3000 Broadway MC 3113, New York, NY 10027, USA
| | | | | |
Collapse
|
49
|
Abstract
Quantum transport is usually cast as an "open" scattering problem, for which available computational methods have not achieved the accuracy of methods for conventional "closed" problems. Here we cast quantum transport as a closed problem and demonstrate fully converged currents for the prototype benzene-dithiolate system. We further report results for carbon-nanotube field-effect transistors, highlighting differences with Si-based devices, e.g., band mixing caused by the gate electric field. We also find that the source-drain current exhibits an intrinsic saturation as a function of the gate voltage.
Collapse
Affiliation(s)
- K Varga
- Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA
| | | |
Collapse
|
50
|
Szentiványi O, Kiss L, Russell JC, Kovács GM, Varga K, Jankovics T, Lesemann S, Xu XM, Jeffries P. Ampelomyces mycoparasites from apple powdery mildew identified as a distinct group based on single-stranded conformation polymorphism analysis of the rDNA ITS region. ACTA ACUST UNITED AC 2005; 109:429-38. [PMID: 15912930 DOI: 10.1017/s0953756204001820] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Pycnidial fungi belonging to the genus Ampelomyces are the most common natural antagonists of powdery mildews worldwide. During a study of the interactions between apple powdery mildew (Podosphaera leucotricha) and Ampelomyces mycoparasites, 52 new Ampelomyces isolates were obtained from P. leucotricha and, in addition, 13 new isolates from other species of the Erysiphaceae in four European countries. Their genetic diversity was screened using single-stranded conformation polymorphism (SSCP) analysis of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA). For comparison, 24 isolates obtained from genetic resource collections or other sources were included in this study. Based on the ITS-SSCP patterns, the isolates were placed in eight groups. The isolates belonged to two types based on their growth in culture. The faster-growing and the slower-growing isolates were included in different SSCP groups. A phylogenetic analysis of the ITS sequences of representatives of these groups confirmed the results obtained with the SSCP method, and showed that the faster-growing isolates do not belong to Ampelomyces as suggested by earlier studies. All the isolates from P. leucotricha fell into a distinct SSCP group of genetically homogeneous isolates. This suggests that Ampelomyces mycoparasites which occur in apple powdery mildew are slightly different from the other Ampelomyces groups which contain mycoparasites from various powdery mildew species. This may be because the main growth period of Ampelomyces mycoparasites in apple powdery mildew is isolated in time from that of Ampelomyces isolates that occur in other species of the Erysiphaceae. P. leucotricha starts its life-cycle early in the season, usually in March-April, while most powdery mildews are active in the same environments only late in the year.
Collapse
Affiliation(s)
- Orsolya Szentiványi
- Plant Protection Institute of the Hungarian Academy of Sciences, PO Box 102, H-1525 Budapest, Hungary
| | | | | | | | | | | | | | | | | |
Collapse
|