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Mukherjee P, Mukhopadhyay TK, Mukherjee M, Roy P, Ghosh R, Sardar PS, Ghosh S. Triplet state spectroscopy reveals involvement of the buried tryptophan residue 310 in Glyceraldehyde-3-phosphate dehydrogenase (GAPD) in the interaction with acrylamide. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 307:123622. [PMID: 37956485 DOI: 10.1016/j.saa.2023.123622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 10/31/2023] [Accepted: 11/04/2023] [Indexed: 11/15/2023]
Abstract
Using conventional steady state and time resolved fluorescence study of the interaction between a multi-tryptophan protein and a quencher, it is difficult, if not impossible to identify the particular tryptophan residue/residues involved in the interaction. In this work we have exemplified the above contention using a multi-tryptophan protein, Glyceraldehyde-3-phosphate dehydrogenase (GAPD) from rabbit muscle having three tryptophan (Trp) residues at positions 84, 193 and 310 and a neutral quencher acrylamide in Tris buffer of pH 7.5. From the steady state and time resolved fluorescence quenching (at 298 K) with acrylamide Ksv, K and kq for the system have been calculated. Low temperature phosphorescence (LTP) spectra at 77 K of GAPD in suitable cryosolvent is known to exhibit two (0,0) bands corresponding to two tryptophan residues 193 and 310. Using the LTP study of free GAPD and GAPD - acrylamide it is possible to identify that the buried Trp 310 residue is specifically involved in the interaction with acrylamide. This is possible without doing any site-directed mutagenesis of GAPD which contains Trp residues at 84, 193 and 310. Tyrosine 320 is also specifically quenched. The results have been corroborated using the molecular docking studies. Molecular Dynamics simulation supports our contention of the involvement of Trp 310 and also shows that the other nearest residues of acrylamide are Val175 and Val232.
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Affiliation(s)
| | - Titas Kumar Mukhopadhyay
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Manini Mukherjee
- Chemical Division, State Unit: Karnataka and Goa, Geological Survey of India, Bangalore 560111, India
| | - Pritam Roy
- Molecular Bacteriology, Katholieke Universiteit Leuven, Belgium
| | - Rina Ghosh
- Department of Chemistry, St. Xavier's College, Kolkata 700016, India
| | - Pinki Saha Sardar
- Department of Chemistry, The Bhawanipur Education Society College, Kolkata 700020, India
| | - Sanjib Ghosh
- Department of Chemistry, Adamas University, Barasat, West Bengal, India.
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Samanta S, Sanyal S, Maity M, Chaudhury M, Ghosh S. Unusual solvent effect of molecular charge transfer complexes: Stacking/non-stacking interaction revealed by characterization of structure and photophysical aspects. JOURNAL OF LUMINESCENCE 2017; 190:403-412. [DOI: 10.1016/j.jlumin.2017.05.067] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
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3
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Paul S, Sepay N, Sarkar S, Roy P, Dasgupta S, Saha Sardar P, Majhi A. Interaction of serum albumins with fluorescent ligand 4-azido coumarin: spectroscopic analysis and molecular docking studies. NEW J CHEM 2017. [DOI: 10.1039/c7nj02335a] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The investigation of the binding of 4-AC to biomolecular systems using photophysical techniques and molecular docking studies.
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Affiliation(s)
- Sandip Paul
- Department of Chemistry
- Presidency University
- Kolkata 700 073
- India
| | - Nasim Sepay
- Department of Chemistry
- Presidency University
- Kolkata 700 073
- India
| | - Shrabana Sarkar
- Department of Chemistry
- Presidency University
- Kolkata 700 073
- India
| | - Pritam Roy
- Department of Chemistry
- Indian Institute of Technology
- Kharagpur
- India
| | - Swagata Dasgupta
- Department of Chemistry
- Indian Institute of Technology
- Kharagpur
- India
| | - Pinki Saha Sardar
- The Department of Chemistry
- The Bhawanipur Education Society College
- Kolkata 700020
- India
| | - Anjoy Majhi
- Department of Chemistry
- Presidency University
- Kolkata 700 073
- India
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Janssen EML, McNeill K. Environmental photoinactivation of extracellular phosphatases and the effects of dissolved organic matter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:889-896. [PMID: 25495644 DOI: 10.1021/es504211x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Alkaline phosphatases are ubiquitous extracellular enzymes in aquatic systems and play a central role in the biogeochemical cycling of phosphorus. Yet, the photochemical stability of phosphatase and effects of natural organic matter (DOM) are not completely understood. We demonstrate that phosphatase activity in natural biofilm samples decreased during sunlight exposure similar to well-defined bacterial phosphatase solutions. Direct photoinactivation was slowed by more than 50% in the presence of redox-active dissolved organic matter (DOM, 10 mgC L(–1)) or a model antioxidant (esculetin, 50 μM), even after light screening effects had been accounted for. Thus, DOM can not only inhibit enzymes (in the dark) or sensitize photodegradation by producing photochemically produced reactive intermediates but can also significantly quench direct photoinactivation of phosphatase. Our data further suggest that direct photooxidation of tryptophan residues within the protein structure are significantly involved in the photoinactivation of phosphatase because a loss of tryptophan-like fluorescence paralleled photoinactivation kinetics and because DOM acted as an antioxidant toward photoinactivation, a phenomenon recently established for the photooxidation of freely dissolved tryptophan. Thus, photoinactivation of phosphatase can be significantly slowed in the presence of naturally occurring antioxidants like DOM. The mechanistic link between tryptophan photooxidation and inactivation of phosphatase may have applicability to other extracellular enzymes but remains to be established.
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Mukherjee M, Ghosh R, Chattopadhyay K, Ghosh S. pH-induced structural change of a multi-tryptophan protein MPT63 with immunoglobulin-like fold: identification of perturbed tryptophan residue/residues. J Biomol Struct Dyn 2015; 33:2145-60. [DOI: 10.1080/07391102.2014.992043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Manini Mukherjee
- Department of Chemistry, Presidency University , Kolkata 700 073, India
| | - Ranendu Ghosh
- Department of Chemical and Biomolecular Engineering, University of Delaware , Newark, DE, USA
| | - Krishnananda Chattopadhyay
- Structural Biology & Bio-Informatics Division, CSIR-Indian Institute of Chemical Biology , Kolkata 700 032, India
| | - Sanjib Ghosh
- Department of Chemistry, Presidency University , Kolkata 700 073, India
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Ghosh G, Mandal DK. Novel unfolding sequence of banana lectin: Folded, unfolded and natively unfolded-like monomeric states in guanidine hydrochloride. Biochimie 2013; 99:138-45. [PMID: 24316282 DOI: 10.1016/j.biochi.2013.11.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 11/23/2013] [Indexed: 11/16/2022]
Abstract
The sequence of unfolding events of dimeric banana lectin (Banlec), as induced by guanidine hydrochloride (GdnHCl), has been investigated by size-exclusion HPLC, fluorescence, far-UV CD, low temperature phosphorescence and selective chemical modification. 8-Anilino-1-naphthalenesulfonate (ANS) binding indicates a structured unfolding intermediate which has been characterized as dissociated monomer by size-exclusion chromatography. Interestingly, the unfolding elution pattern reveals two distinct unfolded states. One is a usual random coil. The other represents a novel species having elution behavior and structural compactness (Stokes radius) similar to dissociated monomer but showing no regular secondary structure as determined by far-UV CD, thus resembling a natively unfolded state. N-Bromosuccinimide (NBS) oxidation shows that single tryptophan residue remains unmodified in dissociated monomer intermediate while the same is oxidized in natively unfolded-like species. Such difference in tryptophan environment in these species is supported by acrylamide quenching studies, and phosphorescence results at 77 K which show a blue-shift of (0,0) band from 414.8 nm to 409.2 nm. The present results reveal subtlety of structural characteristics of unfolded states of Banlec in GdnHCl, which provide important insight in protein unfolding reaction.
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Affiliation(s)
- Goutam Ghosh
- Department of Chemistry, Presidency University, 86/1 College Street, Kolkata 700 073, India
| | - Dipak K Mandal
- Department of Chemistry, Presidency University, 86/1 College Street, Kolkata 700 073, India.
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Mukherjee M, Saha Sardar P, Ghorai SK, Samanta SK, Roy AS, Dasgupta S, Ghosh S. A comparative study of interaction of tetracycline with several proteins using time resolved anisotropy, phosphorescence, docking and FRET. PLoS One 2013; 8:e60940. [PMID: 23593355 PMCID: PMC3623961 DOI: 10.1371/journal.pone.0060940] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 03/04/2013] [Indexed: 11/18/2022] Open
Abstract
A comparative study of the interaction of an antibiotic Tetracycline hydrochloride (TC) with two albumins, Human serum albumin (HSA) and Bovine serum albumin (BSA) along with Escherichia Coli Alkaline Phosphatase (AP) has been presented exploiting the enhanced emission and anisotropy of the bound drug. The association constant at 298 K is found to be two orders of magnitude lower in BSA/HSA compared to that in AP with number of binding site being one in each case. Fluorescence resonance energy transfer (FRET) and molecular docking studies have been employed for the systems containing HSA and BSA to find out the particular tryptophan (Trp) residue and the other residues in the proteins involved in the binding process. Rotational correlation time (θc) of the bound TC obtained from time resolved anisotropy of TC in all the protein-TC complexes has been compared to understand the binding mechanism. Low temperature (77 K) phosphorescence (LTP) spectra of Trp residues in the free proteins (HSA/BSA) and in the complexes of HSA/BSA have been used to specify the role of Trp residues in FRET and in the binding process. The results have been compared with those obtained for the complex of AP with TC. The photophysical behaviour (viz., emission maximum, quantum yield, lifetime and θc) of TC in various protic and aprotic polar solvents has been determined to address the nature of the microenvironment of TC in the protein-drug complexes.
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Affiliation(s)
| | | | | | | | - Atanu Singha Roy
- Department of Chemistry, Indian Institute of Technology, Kharagpur, India
| | - Swagata Dasgupta
- Department of Chemistry, Indian Institute of Technology, Kharagpur, India
| | - Sanjib Ghosh
- Department of Chemistry, Presidency University, Kolkata, India
- * E-mail:
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Molla AR, Mandal DK. Trifluoroethanol-induced conformational change of tetrameric and monomeric soybean agglutinin: role of structural organization and implication for protein folding and stability. Biochimie 2013; 95:204-14. [PMID: 23022144 DOI: 10.1016/j.biochi.2012.09.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 09/13/2012] [Indexed: 11/23/2022]
Abstract
2,2,2-Trifuoroethanol (TFE)-induced conformational structure change of a β-sheet legume lectin, soybean agglutinin (SBA) has been investigated employing its exclusive structural forms in quaternary (tetramer) and tertiary (monomer) states, by far- and near-UV CD, FTIR, fluorescence, low temperature phosphorescence and chemical modification. Far-UV CD results show that, for SBA tetramer, native atypical β-conformation transforms to a highly α-helical structure, with the helical content reaching 57% in 95% TFE. For SBA monomer, atypical β-sheet first converts to typical β-sheet at low TFE concentration (10%), which then leads to a nonnative α-helix at higher TFE concentration. From temperature-dependent studies (5-60 °C) of TFE perturbation, typical β-sheet structure appears to be less stable than atypical β-sheet and the induced helix entails reduced thermal stability. The heat induced transitions are reversible except for atypical to typical β-sheet conversion. FTIR results reveal a partial α-helix conversion at high protein concentration but with quantitative yield. However, aggregation is detected with FTIR at lower TFE concentration, which disappears in more TFE. Near-UV CD, fluorescence and phosphorescence studies imply the existence of an intermediate with native-like secondary and tertiary structure, which could be related to the dissociation of tetramer to monomer. This has been further supported by concentration dependent far-UV CD studies. Chemical modification with N-bromosuccinimide (NBS) shows that all six tryptophans per monomer are solvent-exposed in the induced α-helical conformation. These results may provide novel and important insights into the perturbed folding problem of SBA in particular, and β-sheet oligomeric proteins in general.
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Affiliation(s)
- Anisur R Molla
- Department of Chemistry and Biochemistry, Presidency University, 86/1 College Street, West Bengal, Kolkata 700 073, India
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Ghosh R, Mukherjee M, Chattopadhyay K, Ghosh S. Unusual Optical Resolution of All Four Tryptophan Residues in MPT63 Protein by Phosphorescence Spectroscopy: Assignment and Significance. J Phys Chem B 2012; 116:12489-500. [DOI: 10.1021/jp307526f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ranendu Ghosh
- Structural Biology & Bio-Informatics Division, Indian Institute of Chemical Biology, Kolkata-700 032, India
| | - Manini Mukherjee
- Department of Chemistry, Presidency University, Kolkata 700 073, India
| | - Krishnananda Chattopadhyay
- Structural Biology & Bio-Informatics Division, Indian Institute of Chemical Biology, Kolkata-700 032, India
| | - Sanjib Ghosh
- Department of Chemistry, Presidency University, Kolkata 700 073, India
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Ghosh G, Mandal DK. Differing structural characteristics of molten globule intermediate of peanut lectin in urea and guanidine-HCl. Int J Biol Macromol 2012; 51:188-95. [DOI: 10.1016/j.ijbiomac.2012.05.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 05/07/2012] [Accepted: 05/07/2012] [Indexed: 10/28/2022]
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Mukherjee M, Sardar PS, Ghorai SK, Samanta SK, Roy AS, Dasgupta S, Ghosh S. Interaction of multitryptophan protein with drug: an insight into the binding mechanism and the binding domain by time resolved emission, anisotropy, phosphorescence and docking. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2012; 115:93-104. [PMID: 22884693 DOI: 10.1016/j.jphotobiol.2012.07.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 07/08/2012] [Indexed: 11/17/2022]
Abstract
The interaction of antibiotic Tetracycline hydrochloride (TC) with Alkaline Phosphatase (AP) from Escherichia coli, an important target enzyme in medicinal chemistry, having tryptophan (Trp) residues at 109, 220 and 268 has been studied using the steady state and time resolved emission of the protein and the enhanced emission of the bound drug. The association constant at 298 K (≈10(6) [M](-1)) and the number of binding site (=1) were estimated using the quenched Trp emission of AP, the enhanced emission and the anisotropy of the bound drug. The values of ΔH(0) and ΔS(0) are indicative of electrostatic and H-bonding interaction. The low temperature phosphorescence of free AP and the protein- drug complex and molecular docking comprehensively prove the specific involvement of partially exposed Trp 220 in the binding process without affecting Trp 109 and Trp 268. The Förster energy transfer (ET) efficiency and the rate constant from the Trp residue to TC=0.51 and ≈10(8) s(-1) respectively. Arg 199, Glu 219, Trp 220, Lys 223, Ala 231, Arg 232 and Tyr 234 residues are involved in the binding process. The motional restriction of TC imposed by nearby residues is reflected in the observed life time and the rotational correlation time of bound TC.
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Affiliation(s)
- Manini Mukherjee
- Department of Chemistry, Presidency University, Kolkata 700 073, India
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Mandal P, Mandal DK. Localization and environment of tryptophans in different structural states of concanavalin A. J Fluoresc 2011; 21:2123-32. [PMID: 21748239 DOI: 10.1007/s10895-011-0913-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Accepted: 07/04/2011] [Indexed: 10/18/2022]
Abstract
We have investigated the localization and environment of tryptophan residues in different quaternary and conformational states (tetrameric, dimeric, monomeric and unfolded) of metallized and demetallized concanavalin A (ConA) by selective chemical modification, fluorescence, and phosphorescence. ConA has four tryptophan residues (Trp 40, Trp 88, Trp 109 and Trp 182) per subunit. The pattern of oxidation by N-bromosuccinimide (NBS) shows that NBS modifies, in dimer, only Trp 182 which remains inaccessible in tetramer, two (Trp 88 along with Trp 182) in monomer, all four in unfolded form in presence of EDTA, and three (possibly Trp 40 along with Trp 88 and Trp 182) in unfolded form from native or remetallized ConA. Utilizing wavelength-selective fluorescence approach, we have observed a red edge excitation shift (REES) of 6-8 nm for tetramer and dimer. A more pronounced REES (11 nm) is observed for oxidized monomer compared to REES (3 nm) for unoxidized species. Acrylamide quenching shows the Stern-Volmer constant (K(SV)) for dimer, monomer, unfolded ConA and unfolded apo-ConA being 3.8, 5.2, 12.8, 14.0 M(-1), respectively. Phosphorescence studies at 77 K give more structured spectra, with two (0,0) bands at 406.2 (weak) and 413.2 nm for tetramer. However, a single (0,0) band appears at 413.2 for dimer and 412.6 nm for monomer, while the (0,0) band of the oxidized monomer is red shifted to 414.4 nm. These results may provide important insight into subtlety of organization and environment of tryptophans in the context of folding and structural studies of oligomeric proteins including lectins.
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Affiliation(s)
- Pritha Mandal
- Department of Chemistry & Biochemistry, Presidency University, Kolkata 700 073, India
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Sen D, Mandal DK. Pea lectin unfolding reveals a unique molten globule fragment chain. Biochimie 2011; 93:409-17. [DOI: 10.1016/j.biochi.2010.10.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Accepted: 10/19/2010] [Indexed: 10/18/2022]
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Molla AR, Maity SS, Ghosh S, Mandal DK. Organization and dynamics of tryptophan residues in tetrameric and monomeric soybean agglutinin: studies by steady-state and time-resolved fluorescence, phosphorescence and chemical modification. Biochimie 2009; 91:857-67. [PMID: 19383525 DOI: 10.1016/j.biochi.2009.04.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Accepted: 04/11/2009] [Indexed: 10/20/2022]
Abstract
We have investigated the organization and dynamics of tryptophan residues in tetrameric, monomeric and unfolded states of soybean agglutinin (SBA) by selective chemical modification, steady-state and time-resolved fluorescence, and phosphorescence. Oxidation with N-bromosuccinimide (NBS) modifies two tryptophans (Trp 60 and Trp 132) in tetramer, four (Trp 8, Trp 203 and previous two) in monomer, and all six (Trp 8, Trp 60, Trp 132, Trp 154, Trp 203 and Trp 226) in unfolded state. Utilizing wavelength-selective fluorescence approach, we have observed a red-edge excitation shift (REES) of 10 and 5 nm for tetramer and monomer, respectively. A more pronounced REES (21 nm) is observed after NBS oxidation. These results are supported by fluorescence anisotropy experiments. Acrylamide quenching shows the Stern-Volmer constant (K(SV)) for tetramer, monomer and unfolded SBA being 2.2, 5.0 and 14.6 M(-1), respectively. Time-resolved fluorescence studies exhibit biexponential decay with the mean lifetime increasing along tetramer (1.0 ns) to monomer (1.9 ns) to unfolded (3.6 ns). Phosphorescence studies at 77 K give more structured spectra, with two (0,0) bands at 408.6 (weak) and 413.2 nm for tetramer. However, a single (0,0) band appears at 411.8 and 407.2 nm for monomer and unfolded SBA, respectively. The exposure of hydrophobic surface in SBA monomer has been examined by 8-anilino-1-naphthalenesulfonate (ANS) binding, which shows approximately 20-fold increase in ANS fluorescence compared to that for tetramer. The mean lifetime of ANS also shows a large increase (12.0 ns) upon binding to monomer. These results may provide important insight into the role of tryptophans in the folding and association of SBA, and oligomeric proteins in general.
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Affiliation(s)
- Anisur R Molla
- Department of Chemistry & Biochemistry, Presidency College, 86/1 College Street, Kolkata 700 073, West Bengal, India
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Samanta S, Sardar PS, Maity SS, Pal A, Roy MB, Ghosh S. Comparative photophysical behaviour of naphthalene-linked crown ethers and aza crown ethers of varying cavity dimensions. J CHEM SCI 2007. [DOI: 10.1007/s12039-007-0025-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Samanta S, Roy MB, Ghosh S. Time resolved studies of dual emission and photoinduced energy transfer in a Tris methoxy coumarin derivative of a cryptand and its complex with Tb(NO3)3. Chem Phys 2006. [DOI: 10.1016/j.chemphys.2006.07.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bhattacharyya S, Basu Roy M, Ghosh S. The dependence of photoinduced energy transfer on the orientation of the acceptor with respect to the π-plane of the donor in naphthalene-linked crown ether–Tb3+ complexes. Chem Phys 2004. [DOI: 10.1016/j.chemphys.2003.12.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Ghosh S, Misra A, Ozarowski A, Maki AH. Low-Temperature Study of Photoinduced Energy Transfer from Tryptophan Residues of Escherichia coli Alkaline Phosphatase to Bound Terbium. J Phys Chem B 2003. [DOI: 10.1021/jp030522b] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sanjib Ghosh
- Department of Chemistry, Presidency College, 86/1 College Street, Calcutta 700073, India, and the Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616
| | - Ajay Misra
- Department of Chemistry, Presidency College, 86/1 College Street, Calcutta 700073, India, and the Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616
| | - Andrzej Ozarowski
- Department of Chemistry, Presidency College, 86/1 College Street, Calcutta 700073, India, and the Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616
| | - August H. Maki
- Department of Chemistry, Presidency College, 86/1 College Street, Calcutta 700073, India, and the Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616
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Ozarowski A, Misra A, Ghosh S, Maki AH. Spin−Lattice Relaxation of the Tryptophan Triplet State Varies with Its Protein Environment. J Phys Chem B 2002. [DOI: 10.1021/jp014272f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrzej Ozarowski
- Department of Chemistry, University of California, Davis, Davis, California 95616
| | - Ajay Misra
- Department of Chemistry, University of California, Davis, Davis, California 95616
| | - Sanjib Ghosh
- Department of Chemistry, University of California, Davis, Davis, California 95616
| | - August H. Maki
- Department of Chemistry, University of California, Davis, Davis, California 95616
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