Search

Your search keyword '"Singha, Subhankar"' showing total 45 results
Start Over Author "Singha, Subhankar"
45 results on '"Singha, Subhankar"'

4. The hepatic compensatory response to elevated systemic sulfide promotes diabetes

Author

Carter, Roderick N., Gibbins, Matthew T.G., Barrios-Llerena, Martin E., Wilkie, Stephen E., Freddolino, Peter L., Libiad, Marouane, Vitvitsky, Victor, Emerson, Barry, Le Bihan, Thierry, Brice, Madara, Su, Huizhong, Denham, Scott G., Homer, Natalie Z.M., Mc Fadden, Clare, Tailleux, Anne, Faresse, Nourdine, Sulpice, Thierry, Briand, Francois, Gillingwater, Tom, Ahn, Kyo Han, Singha, Subhankar, McMaster, Claire, Hartley, Richard C., Staels, Bart, Gray, Gillian A., Finch, Andrew J., Selman, Colin, Banerjee, Ruma, and Morton, Nicholas M.

Published
2021
Full Text
View/download PDF

5. Hypothalamic-Pituitary Axis Regulates Hydrogen Sulfide Production

Author

Hine, Christopher, Kim, Hyo-Jeong, Zhu, Yan, Harputlugil, Eylul, Longchamp, Alban, Matos, Marina Souza, Ramadoss, Preeti, Bauerle, Kevin, Brace, Lear, Asara, John M., Ozaki, C. Keith, Cheng, Sheue-yann, Singha, Subhankar, Ahn, Kyo Han, Kimmelman, Alec, Fisher, Ffolliott M., Pissios, Pavlos, Withers, Dominic J., Selman, Colin, Wang, Rui, Yen, Kelvin, Longo, Valter D., Cohen, Pinchas, Bartke, Andrzej, Kopchick, John J., Miller, Richard, Hollenberg, Anthony N., and Mitchell, James R.

Published
2017
Full Text
View/download PDF

6. Interactive Twin Intramolecular Hydrogen Bonds Enable Bright, S‐Blue Emissive, Environment‐Insensitive Single‐Benzene Fluorophores.

Author

Sarkar, Sourav, Shil, Anushree, Jun, Yong Woong, Yang, Yun Jae, Choi, Wanuk, Singha, Subhankar, and Ahn, Kyo Han

Subjects
FLUOROPHORES, HYDROGEN bonding, HYDROGEN sulfide, ANILINE derivatives, FLUORESCENT probes, BAND gaps
Abstract

Small‐molecule dyes that emit blue fluorescence, particularly those that emit in the S‐blue region, are limited in number. Functionalization of benzene with electron‐donating and ‐accepting groups generates single‐benzene fluorophores (SBFs) with tunable emission properties. By exploring the unprecedented, interactive twin intramolecular H‐bonds, a novel type of SBFs that exhibits several notable features for bioimaging applications is developed. Specifically, aniline derivatives bearing two carbonyl/carboxyl groups at ortho‐positions have interactive H‐bonds, which lead to conformational restriction, suppressed solvation, and increased HOMO‐LUMO energy gaps from those of the conventional SBFs that have non‐interactive H‐bonds. The interactive H‐bonds are manifested by notable photophysical properties among the new SBFs, such as S‐blue emissive, bright, photo‐ and chemo‐stable, solid‐state‐emissive, and environment (pH, polarity, and viscosity)‐insensitive. The use of the highly faceted dye system to develop a reliable fluorescent probe, organelle‐staining dyes, and a fluorescence‐resonance‐energy‐transfer probe for hydrogen sulfide demonstrates its potential in bioimaging applications. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

11. Host assisted molecular recognition by human serum albumin: Study of molecular recognition controlled protein/drug mimic binding in a microfluidic channel

Author

Mukherjee, Dipanjan, primary, Singh, Priya, additional, Singh, Soumendra, additional, Roy, Debanjona Singh, additional, Singha, Subhankar, additional, Pal, Uttam, additional, Sengupta, Jhimli, additional, Obaid, Rami J., additional, Ahmed, Saleh A., additional, Dasgupta, Tanusri Saha, additional, Das, Ranjan, additional, and Pal, Samir Kumar, additional

Published
2021
Full Text
View/download PDF

12. The hepatic compensatory response to elevated systemic sulfide impairs medium chain fat oxidation and promotes diabetes

Author

Carter, Roderick N., Gibbins, Matthew T.G., Barrios-Llerena, Martin E., Wilkie, Stephen E., Freddolino, Peter L., Libiad, Marouane, Vitvitsky, Victor, Emerson, Barry, Le Bihan, Thierry, Brice, Madara, Su, Huizhong, Denham, Scott, Homer, Natalie Z.M., Mc Fadden, Clare, Tailleux, Anne, Faresse, Nourdine, Sulpice, Thierry, Briand, Francois, Gillingwater, Tom, Ahn, Kyo Han, Singha, Subhankar, McMaster, Claire, Hartley, Richard C., Staels, Bart, Gray, Gillian, Finch, Andrew J., Selman, Colin, Banerjee, Ruma, and Morton, Nicholas M.

Abstract

Impaired hepatic glucose and lipid metabolism are hallmarks of type–2 diabetes. Increased sulfide production from cysteine, or sulfide–donor compounds, may beneficially regulate hepatic metabolism. Disposal of sulfide through the sulfide oxidation pathway (SOP) is critical for maintaining sulfide within a safe physiological range. We show that mice lacking the liver–enriched mitochondrial SOP enzyme thiosulfate sulfur–transferase ( Tst —/— mice) exhibit high circulating sulfide, increased gluconeogenesis, hypertriglyceridemia and fatty liver, despite whole–body insulin– sensitisation. Unexpectedly, hepatic sulfide levels were normal in Tst —/— mice, a result of homeostatic induction of mitochondrial sulfide disposal and glutathione excretion associated with net suppression of protein persulfidation and nuclear respiratory factor–2 target proteins. Proteomic and persulfidomic profiling converged on hepatic lipid metabolism, revealing a deficit in medium–chain fatty acid oxidation in Tst —/— mice. In conclusion our findings have implications for sulfide-donor strategies in the context of liver function and metabolic disease.

Published
2020
Full Text
View/download PDF

14. The hepatic compensatory response to elevated systemic sulfide promotes diabetes

Author

Carter, Roderick N., primary, Gibbins, Matthew T.G., additional, Barrios-Llerena, Martin E., additional, Wilkie, Stephen E., additional, Freddolino, Peter L., additional, Libiad, Marouane, additional, Vitvitsky, Victor, additional, Emerson, Barry, additional, Bihan, Thierry Le, additional, Brice, Madara, additional, Su, Huizhong, additional, Denham, Scott G., additional, Homer, Natalie Z.M., additional, Fadden, Clare Mc, additional, Tailleux, Anne, additional, Faresse, Nourdine, additional, Sulpice, Thierry, additional, Briand, Francois, additional, Gillingwater, Tom, additional, Ahn, Kyo Han, additional, Singha, Subhankar, additional, McMaster, Claire, additional, Hartley, Richard C., additional, Staels, Bart, additional, Gray, Gillian A., additional, Finch, Andrew J., additional, Selman, Colin, additional, Banerjee, Ruma, additional, and Morton, Nicholas M., additional

Published
2020
Full Text
View/download PDF

15. A systematic study on the discrepancy of fluorescence properties between in solutions and in cells: super-bright, environment-insensitive benzocoumarin dyes

Author

Reo, Ye Jin, primary, Jun, Yong Woong, additional, Cho, Seo Won, additional, Jeon, Jinseong, additional, Roh, Hajung, additional, Singha, Subhankar, additional, Dai, Mingchong, additional, Sarkar, Sourav, additional, Kim, Hye Rim, additional, Kim, Sojeong, additional, Jin, Yusung, additional, Jung, Yun Lim, additional, Yang, Yun Jae, additional, Ban, Changil, additional, Joo, Jinmyoung, additional, and Ahn, Kyo Han, additional

Published
2020
Full Text
View/download PDF

27. Hypothalamic-Pituitary Axis Regulates Hydrogen Sulfide Production

Author

Hine, Christopher, Kim, Hyo-Jeong, Zhu, Yan, Harputlugil, Eylul, Longchamp, Alban, Matos, Marina Souza, Ramadoss, Preeti, Bauerle, Kevin, Brace, Lear, Asara, John M., Ozaki, C. Keith, Cheng, Sheue-yann, Singha, Subhankar, Ahn, Kyo Han, Kimmelman, Alec, Fisher, Ffolliott M., Pissios, Pavlos, Withers, Dominic J., Selman, Colin, Wang, Rui, Yen, Kelvin, Longo, Valter D., Cohen, Pinchas, Bartke, Andrzej, Kopchick, John J., Miller, Richard, Hollenberg, Anthony N., Mitchell, James R., and Wellcome Trust

Subjects
autophagy, Hypothalamo-Hypophyseal System, Article, Endocrinology & Metabolism, Mice, FGF21, longevity, LIVED MUTANT MICE, CALORIE RESTRICTION, 1101 Medical Biochemistry And Metabolomics, Animals, Dextrothyroxine, Hydrogen Sulfide, LIFE-SPAN EXTENSION, Insulin-Like Growth Factor I, DIETARY RESTRICTION, IRS-1, AMES DWARF MICE, cystathionine γ-lyase, GENE-EXPRESSION, Mice, Knockout, Science & Technology, CYSTATHIONINE-GAMMA-LYASE, STRESS RESISTANCE, Cystathionine gamma-Lyase, 0601 Biochemistry And Cell Biology, THYROID-HORMONE RECEPTOR, Cell Biology, GROWTH-FACTOR I, hypopituitary dwarfism, equipment and supplies, thyroid hormone, Liver, Growth Hormone, IGF-1, Female, Life Sciences & Biomedicine
Abstract

Decreased growth hormone (GH) and thyroid hormone (TH) signaling are associated with longevity and metabolic fitness. The mechanisms underlying these benefits are poorly understood, but may overlap with those of dietary restriction (DR), which imparts similar benefits. Recently we discovered that hydrogen sulfide (H2S) is increased upon DR and plays an essential role in mediating DR benefits across evolutionary boundaries. Here we found increased hepatic H2S production in long-lived mouse strains of reduced GH and/or TH action, and in a cell-autonomous manner upon serum withdrawal in vitro. Negative regulation of hepatic H2S production by GH and TH was additive and occurred via distinct mechanisms, namely direct transcriptional repression of the H2S-producing enzyme cystathionine γ-lyase (CGL) by TH, and substrate-level control of H2S production by GH. Mice lacking CGL failed to downregulate systemic T4 metabolism and circulating IGF-1, revealing an essential role for H2S in the regulation of key longevity-associated hormones.

Published
2016

33. A two-photon fluorescent probe for lysosomal zinc ions

Author

Lee, Hyo-Jun, primary, Cho, Chang-Woo, additional, Seo, Hyewon, additional, Singha, Subhankar, additional, Jun, Yong Woong, additional, Lee, Kyung-Ha, additional, Jung, Youngseob, additional, Kim, Kyong-Tai, additional, Park, Seongjun, additional, Bae, Sung Chul, additional, and Ahn, Kyo Han, additional

Published
2016
Full Text
View/download PDF

34. Two-Photon Absorbing Dyes with Minimal Autofluorescence in Tissue Imaging: Application to in Vivo Imaging of Amyloid-β Plaques with a Negligible Background Signal

Author

Kim, Dokyoung, primary, Moon, Hyunsoo, additional, Baik, Sung Hoon, additional, Singha, Subhankar, additional, Jun, Yong Woong, additional, Wang, Taejun, additional, Kim, Ki Hean, additional, Park, Byung Sun, additional, Jung, Junyang, additional, Mook-Jung, Inhee, additional, and Ahn, Kyo Han, additional

Published
2015
Full Text
View/download PDF

37. A structural remedy toward bright dipolar fluorophores in aqueous media

Author

Singha, Subhankar, primary, Kim, Dokyoung, additional, Roy, Basab, additional, Sambasivan, Sunderraman, additional, Moon, Hyunsoo, additional, Rao, Alla Sreenivasa, additional, Kim, Jin Yong, additional, Joo, Taiha, additional, Park, Jae Woo, additional, Rhee, Young Min, additional, Wang, Taejun, additional, Kim, Ki Hean, additional, Shin, Youn Ho, additional, Jung, Junyang, additional, and Ahn, Kyo Han, additional

Published
2015
Full Text
View/download PDF

40. Ratiometric Fluorescence Detection of Anthrax Biomarker with EuIII-EDTA Functionalized Mixed Poly(diacetylene) Liposomes.

Author

Seo, Hyewon, Singha, Subhankar, and Ahn, Kyo Han

Subjects
LIPOSOMES, ANTHRAX, BIOMARKERS
Abstract

Anthrax, a bacteriogenic fatal infectious disease that is harmful to humans, requires the early and ready detection of its bacterial endospores. We report herein the use of poly(diacetylene acid) derived liposomes functionalized with EuIII-EDTA complexes as a ratiometric fluorescence detection system for dipicolinate, an anthrax biomarker and major component of the endospores. The red fluorescence of the polymerized liposomes provides a built-in reference signal to monitor the relative change of the europium luminescence sensitized by the bound dipicolinate relative to the reference liposome emission. The liposome-based integrated sensing system shows reasonable sensitivity as well as remarkable selectivity toward dipicolinate over other structurally related analytes. Paper strip sensors based on the polymerized liposomes are also prepared for the visible detection of dipicolinate. [ABSTRACT FROM AUTHOR]

Published
2017
Full Text
View/download PDF

44. Toward a Selective, Sensitive, Fast-Responsive, and Biocompatible Two-Photon Probe for Hydrogen Sulfide in Live Cells.

Author

Singha, Subhankar, Dokyoung Kim, Hyunsoo Moon, Taejun Wang, Ki Hean Kim, Youn Ho Shin, Junyang Jung, Eunseok Seo, Sang-Joon Lee, and Kyo Han Ahn

Subjects
*HYDROGEN sulfide, *NITRIC oxide, *CARBON dioxide, *FLUORESCENT probes, *CYSTEINE, *GLUTATHIONE
Abstract

Hydrogen sulfide has emerged as an exciting endogenous gasotransmitter in addition to nitric oxide and carbon dioxide. Noninvasive detection methods for hydrogen sulfide thus become indispensable tools for studying its diverse roles in biological systems. Accordingly, fluorescent probes for hydrogen sulfide have received great attention in recent years. A practically useful fluorescent probe for bioimaging of hydrogen sulfide should be selective, sensitive, fast-responsive, biocompatible, observable in the biological optical window, and capable of deep-tissue imaging. These sensing properties, however, are extremely difficult to achieve at the same time. Disclosed here is the two-photon fluorescent probe that meets all of these criteria. The probe belongs to a Michael acceptor system, which raised a serious selectivity issue over the competing biothiols such as cysteine and glutathione. We have addressed the selectivity issue by optimizing the electronic and steric interactions between biothiols and the probe, in addition to achieving very high sensitivity, fast-response, and biocompatibility. Also, the sensing mechanism suggested in the literature was revised. The probe thus enables us to image the endogenously produced hydrogen sulfide with negligible interference from other biothiols in live cells. The excellent sensing properties of the probe combined with its capability of bioimaging thus make it a practically useful tool for further studying biological roles of hydrogen sulfide. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

45. Modulation of Kinetic Pathways of Enzyme-Substrate Interaction in a Microfluidic Channel: Nanoscopic Water Dynamics as a Switch.

Author

Singh P, Mukherjee D, Singha S, Das R, and Pal SK

Subjects
Anions metabolism, Cations metabolism, Equipment Design, Fluorescence, Kinetics, Substrate Specificity, Surface-Active Agents metabolism, Chymotrypsin metabolism, Coumarins metabolism, Lab-On-A-Chip Devices, Micelles, Oligopeptides metabolism, Water metabolism
Abstract

Enzyme-mediated catalysis is attributed to enzyme-substrate interactions, with models such as "induced fit" and "conformational selection" emphasizing the role of protein conformational transitions. The dynamic nature of the protein structure, thus, plays a crucial role in molecular recognition and substrate binding. As large-scale protein motions are coupled to water motions, hydration dynamics play a key role in protein dynamics, and hence, in enzyme catalysis. Here, microfluidic techniques and time-dependent fluorescence Stokes shift (TDFSS) measurements are employed to elucidate the role of nanoscopic water dynamics in the interaction of an enzyme, α-Chymotrypsin (CHT), with a substrate, Ala-Ala-Phe-7-amido-4-methylcoumarin (AMC) in the cationic reverse micelles of benzylhexadecyldimethylammonium chloride (BHDC/benzene) and anionic reverse micelles of sodium bis(2-ethylhexyl)sulfosuccinate (AOT/benzene). The kinetic pathways unraveled from the microfluidic setup are consistent with the "conformational selection" fit for the interaction of CHT with AMC in the cationic reverse micelles, whereas an "induced fit" mechanism is indicated for the anionic reverse micelles. In the cationic reverse micelles of BHDC, faster hydration dynamics (≈550 ps) aid the pathway of "conformational selection", whereas in the anionic reverse micelles of AOT, the significantly slower dynamics of hydration (≈1600 ps) facilitate an "induced fit" mechanism for the formation of the final enzyme-substrate complex. The role of water dynamics in dictating the mechanism of enzyme-substrate interaction becomes further manifest in the neutral reverse micelles of Brij-30 and Triton X-100. In the former, the faster water dynamics aid the "conformational selection" pathway, whereas the significantly slower dynamics of water molecules in the latter are conducive to the "induced fit" mechanism in the enzyme-substrate interaction. Thus, nanoscopic water dynamics act as a switch in modulating the pathway of recognition of an enzyme (CHT) by the substrate (AMC) in reverse micelles., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Published
2019
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results