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Garg M, Sharma D, Kaur G, Rawat J, Goyal B, Kumar S, Kumar R. Factor defining the effects of tetraalkylammonium chloride on stability, folding, and dynamics of horse cytochrome c. Int J Biol Macromol 2024; 276:133713. [PMID: 38986993 DOI: 10.1016/j.ijbiomac.2024.133713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/04/2024] [Accepted: 07/05/2024] [Indexed: 07/12/2024]
Abstract
This article describes the molecular mechanism by which tetraalkylammonium chloride ([R4N]Cl: R- = methyl (Me), ethyl (Et), propyl (Pr),butyl (Bu)) modulates the stability, folding, and dynamics of cytochrome c (Cyt c). Analysis of [R4N]Cl effects on thermal/chemical denaturations, millisecond refolding/unfolding kinetics, and slow CO-association kinetics of Cyt c without and with denaturant providing some significant results: (i) [R4N]Cl decreasing the unfolding free energy estimated by thermodynamic and kinetic analysis of thermal/chemical denaturation curves and kinetic chevrons (Log kobs-[GdmCl]) of Cyt c, respectively (ii) hydrophobicity of R-group of [R4N]Cl, preferential inclusion of [R4N]Cl at the protein surface, and destabilizing enthalpic attractive interactions of [Me4N]Cl and steric entropic interactions of [Et4N]Cl,[Pr4N]Cl and [Bu4N]Cl with protein contribute to [R4N]Cl-induced decrease thermodynamic stability of Cyt c (iii) [R4N]Cl exhibits an additive effect with denaturant to decrease thermodynamic stability and refolding rates of Cyt c (iv) low concentrations of [R4N]Cl (≤ 0.5 M) constrain the motional dynamics while the higher concentrations (>0.75 M [R4N]Cl) enhance the structural-fluctuations that denture protein (v) hydrophobicity of R-group of [R4N]Cl alters the [denaturant]-dependent conformational stability, refolding-unfolding kinetics, and CO-association kinetics of Cyt c. Furthermore, the MD simulations depicted that the addition of 1.0 M of [R4N]Cl increased the conformational fluctuations in Cyt c leading to decreased structural stability in the order [Me4N]Cl < [Et4N]Cl < [Pr4N]Cl < [Bu4N]Cl consistent with the experimental results.
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Affiliation(s)
- Mansi Garg
- Department of Chemistry, Central University of Punjab, Bathinda 151001, India
| | - Deepak Sharma
- Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39A, Academy of Scientific & Innovative Research, Chandigarh, India
| | - Gurmeet Kaur
- Department of Chemistry and Biochemistry, Thapar Institute of Engineering and Technology, Patiala 147004, India
| | - Jayanti Rawat
- Department of Chemistry, Central University of Punjab, Bathinda 151001, India
| | - Bhupesh Goyal
- Department of Chemistry and Biochemistry, Thapar Institute of Engineering and Technology, Patiala 147004, India
| | - Sumit Kumar
- Department of Chemistry, Central University of Punjab, Bathinda 151001, India
| | - Rajesh Kumar
- Department of Chemistry, Central University of Punjab, Bathinda 151001, India.
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2
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Quasi-native transition and self-diffusion of proteins in water-glycerol mixture. Biophys Chem 2020; 257:106274. [DOI: 10.1016/j.bpc.2019.106274] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/10/2019] [Accepted: 10/21/2019] [Indexed: 01/03/2023]
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3
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Kumar R, Kumar R, Sharma D, Garg M, Kumar V, Agarwal MC. Macromolecular crowding-induced molten globule states of the alkali pH-denatured proteins. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:1102-1114. [DOI: 10.1016/j.bbapap.2018.08.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 07/07/2018] [Accepted: 08/30/2018] [Indexed: 11/26/2022]
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Word TA, Larsen RW. Time resolved calorimetry of photo-induced folding in horse heart cytochrome c at high pH. Arch Biochem Biophys 2016; 615:10-14. [PMID: 28041937 DOI: 10.1016/j.abb.2016.12.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 12/27/2016] [Accepted: 12/28/2016] [Indexed: 10/20/2022]
Abstract
Here the molar volume and enthalpy changes associated with the early events in the folding of ferrocytochrome c (Cc) at high pH have been examined using time resolved photoacoustic calorimetry (PAC). The data reveal an overall volume change of 1.3 ± 0.3 mL mol-1 and an enthalpy change of 13 ± 7 kcal mol -1 occurring subsequent to photodissociation of the unfolded CO bound Cc species in <∼20 ns. Two additional kinetic phases are observed that are associated with non-native His binding (ΔH and ΔV of 2 ± 4 kcal mol-1 and -0.5 mL mol-1, τ ∼ 2.5 μs ) and Met binding (ΔH and ΔV -0.4 ± 2 kcal mol-1 and -0.1 ± 0.1 mL mol-1, τ∼ 660 ns). Considering only protein conformational changes (excluding volume and enthalpies associated with heme ligation events) the initial conformational event exhibits a ΔH and ΔV of 6 ± 3 kcal mol-1 and -3±0.1 mL mol-1, respectively, that are attributed to a small contraction of the unfolded protein. The corresponding enthalpy associated with both native and non-native ligand binding are found to be -5±4 kcal mol-1 (Fe-Met) and +20 ± 4 kcal mol-1 (Fe-His) with the change in volume for both phases being essential negligible. This would indicate that non-native ligand binding likely occurs from an already collapsed conformation.
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Affiliation(s)
- Tarah A Word
- Department of Chemistry, University of South Florida, 4202 East Fowler Ave., Tampa, FL 33602 USA
| | - Randy W Larsen
- Department of Chemistry, University of South Florida, 4202 East Fowler Ave., Tampa, FL 33602 USA.
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Kumar R. Analysis of the pH-dependent thermodynamic stability, local motions, and microsecond folding kinetics of carbonmonoxycytochrome c. Arch Biochem Biophys 2016; 606:16-25. [DOI: 10.1016/j.abb.2016.07.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 06/11/2016] [Accepted: 07/13/2016] [Indexed: 10/21/2022]
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Jain R, Kumar R, Kumar S, Chhabra R, Agarwal MC, Kumar R. Analysis of the pH-dependent stability and millisecond folding kinetics of horse cytochrome c. Arch Biochem Biophys 2015; 585:52-63. [DOI: 10.1016/j.abb.2015.09.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 09/10/2015] [Accepted: 09/14/2015] [Indexed: 11/26/2022]
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7
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Yasin UM, Sashi P, Bhuyan AK. Expansion and Internal Friction in Unfolded Protein Chain. J Phys Chem B 2013; 117:12059-64. [DOI: 10.1021/jp408718c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- U. Mahammad Yasin
- School of Chemistry, University of Hyderabad, Hyderabad 500
046, India
| | - Pulikallu Sashi
- School of Chemistry, University of Hyderabad, Hyderabad 500
046, India
| | - Abani K. Bhuyan
- School of Chemistry, University of Hyderabad, Hyderabad 500
046, India
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8
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Kumar R, Jain R, Kumar R. Viscosity-dependent structural fluctuation of the M80-containing Ω-loop of horse ferrocytochrome c. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2013.04.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Kim J, Park J, Lee T, Pak Y, Lim M. Dynamics of geminate rebinding of CO to cytochrome c in guanidine HCl probed by femtosecond vibrational spectroscopy. J Phys Chem B 2013; 117:4934-44. [PMID: 23590118 DOI: 10.1021/jp401481q] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Femtosecond vibrational spectroscopy was used to probe the rebinding dynamics of CO to cytochrome c (Cytc) in 1.8 and 7 M guanidine HCl (GdnHCl) after photodeligation of the corresponding CO-bound protein in D2O buffer (pD = 7.4) at 283 K. Geminate rebinding (GR) dynamics of CO to the folded Cytc in 1.8 M GdnHCl (nCytc) is similar to that to chemically modified cytochrome c (cCytc), suggesting that the overall conformations of nCytcCO and cCytcCO are similar. About 86% of the dissociated CO molecules were geminately rebound to nCytc nonexponentially within 1 ns. The efficient GR of CO to the folded Cytc can be attributed to the organized protein matrix near the active site of nCytc that provides an efficient trap for the diffusing CO ligand after photodissociation. Although the concentration of nCytc did not affect its GR yield of CO, GR yield of CO to the unfolded Cytc in 7 M GdnHCl (uCytc) increased from 5 to 30% as the protein concentration increased from 0.3 to 9 mM. Time-resolved spectra of the (13)CO dissociated from both 9 mM nCytc(13)CO and 9 mM uCytc(13)CO showed a growing band with a peak at 2090 cm(-1) on the picosecond time scale, which was assigned to (13)CO in D2O solvent. At 1 ns, the fraction of the CO band in the solvent was about 10% of the nascent photodeligated protein in nCytc and more than 50% in the concentrated uCytc. Whereas a small opening in the active site of nCytc is responsible for the ultrafast escape of CO to solution in the folded protein, a large fraction of the CO escape to the solvent in uCytc results from the denatured structure of the active site in the unfolded protein. The spectrum of the CO dissociated from the concentrated uCytcCO contained a band that decayed as efficiently as that for the folded protein, suggesting that some fraction of uCytcCO might form aggregates even in 7 M denaturant, such that the aggregate acts as an efficient trap for the diffusing CO after deligation. No hint of precipitate in the concentrated uCytcCO and protein refolding upon dilution of the GdnHCl indicate that the aggregate does not grow continuously but remains as a soluble oligomer. The delayed appearance of the solvated CO and the inefficient GR of CO in uCytcCO suggest that the monomeric unfolded CytcCO so loosely arranged that the protein matrix cannot trap CO efficiently but the bound CO is still buried within hydrophobic residues even under the harsh denaturation condition.
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Affiliation(s)
- Jooyoung Kim
- Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan, 609-735 Korea
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Jain R, Kaur S, Kumar R. Guanidine hydrochloride-induced alkali molten globule model of horse ferrocytochrome c. J Biochem 2012; 153:161-77. [DOI: 10.1093/jb/mvs134] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Sashi P, Yasin UM, Bhuyan AK. Unfolding action of alcohols on a highly negatively charged state of cytochrome C. Biochemistry 2012; 51:3273-83. [PMID: 22439732 DOI: 10.1021/bi201716r] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
It is well-known that hydrophobic effect play a major role in alcohol-protein interactions leading to structure unfolding. Studies with extremely alkaline cytochrome c (U(B) state, pH 13) in the presence of the first four alkyl alcohols suggests that the hydrophobic effect persistently overrides even though the protein carries a net charge of -17 under these conditions. Equilibrium unfolding of the U(B) state is accompanied by an unusual expansion of the chain involving an intermediate, I(alc), from which water is preferentially excluded, the extent of water exclusion being greater with the hydrocarbon content of the alcohol. The mobility and environmental averaging of side chains in the I(alc) state are generally constrained relative to those in the U(B) state. A few nuclear magnetic resonance-detected tertiary interactions are also found in the I(alc) state. The fact that the I(alc) state populates at low concentrations of methanol and ethanol and the fact that the extent of chain expansion in this state approaches that of the U(B) state indicate a definite influence of electrostatic repulsion severed by the low dielectric of the water/alcohol mixture. Interestingly, the U(B) ⇌ I(alc) segment of the U(B) ⇌ I(alc) ⇌ U equilibrium, where U is the unfolded state, accounts for roughly 85% of the total number of water molecules preferentially excluded in unfolding. Stopped-flow refolding results report on a submillisecond hydrophobic collapse during which almost the entire buried surface area associated with the U(B) state is recovered, suggesting the overwhelming influence of hydrophobic interaction over electrostatic repulsions.
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Affiliation(s)
- Pulikallu Sashi
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India
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Roterman I, Konieczny L, Banach M, Jurkowski W. Intermediates in the protein folding process: a computational model. Int J Mol Sci 2011; 12:4850-60. [PMID: 21954329 PMCID: PMC3179136 DOI: 10.3390/ijms11084850] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 06/07/2011] [Accepted: 07/25/2011] [Indexed: 11/25/2022] Open
Abstract
The paper presents a model for simulating the protein folding process in silico. The two-step model (which consists of the early stage—ES and the late stage—LS) is verified using two proteins, one of which is treated (according to experimental observations) as the early stage and the second as an example of the LS step. The early stage is based solely on backbone structural preferences, while the LS model takes into account the water environment, treated as an external hydrophobic force field and represented by a 3D Gauss function. The characteristics of 1ZTR (the ES intermediate, as compared with 1ENH, which is the LS intermediate) confirm the link between the gradual disappearance of ES characteristics in LS structural forms and the simultaneous emergence of LS properties in the 1ENH protein. Positive verification of ES and LS characteristics in these two proteins (1ZTR and 1ENH respectively) suggest potential applicability of the presented model to in silico protein folding simulations.
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Affiliation(s)
- Irena Roterman
- Department of Bioinformatics and Telemedicine, Medical College, Jagiellonian University, Lazarza 16, 31-530 Krakow, Poland; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +48-12-619-96-94; Fax: +48-12-619-96-93
| | - Leszek Konieczny
- Chair of Medical Biochemistry, Medical College, Jagiellonian University, Kopernika 7, 31-034 Krakow, Poland; E-Mail:
| | - Mateusz Banach
- Faculty of Physics, Astronomy, Applied Computer Science, Jagiellonian University, Reymonta 4, 30-059 Krakow, Poland; E-Mail:
| | - Wiktor Jurkowski
- Department of Bioinformatics and Telemedicine, Medical College, Jagiellonian University, Lazarza 16, 31-530 Krakow, Poland; E-Mail:
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Choi J, Jung YO, Lee JH, Yang C, Kim B, Ihee H. Folding Dynamics of Ferrocytochrome c in a Denaturant-Free Environment Probed by Transient Grating Spectroscopy. Chemphyschem 2008; 9:2708-14. [DOI: 10.1002/cphc.200800280] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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14
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Kim S, Chung JK, Kwak K, Bowman SEJ, Bren KL, Bagchi B, Fayer MD. Native and unfolded cytochrome c--comparison of dynamics using 2D-IR vibrational echo spectroscopy. J Phys Chem B 2008; 112:10054-63. [PMID: 18646797 PMCID: PMC2671645 DOI: 10.1021/jp802246h] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Unfolded vs native CO-coordinated horse heart cytochrome c (h-cyt c) and a heme axial methionine mutant cyt c552 from Hydrogenobacter thermophilus ( Ht-M61A) are studied by IR absorption spectroscopy and ultrafast 2D-IR vibrational echo spectroscopy of the CO stretching mode. The unfolding is induced by guanidinium hydrochloride (GuHCl). The CO IR absorption spectra for both h-cyt c and Ht-M61A shift to the red as the GuHCl concentration is increased through the concentration region over which unfolding occurs. The spectra for the unfolded state are substantially broader than the spectra for the native proteins. A plot of the CO peak position vs GuHCl concentration produces a sigmoidal curve that overlays the concentration-dependent circular dichroism (CD) data of the CO-coordinated forms of both Ht-M61A and h-cyt c within experimental error. The coincidence of the CO peak shift curve with the CD curves demonstrates that the CO vibrational frequency is sensitive to the structural changes induced by the denaturant. 2D-IR vibrational echo experiments are performed on native Ht-M61A and on the protein in low- and high-concentration GuHCl solutions. The 2D-IR vibrational echo is sensitive to the global protein structural dynamics on time scales from subpicosecond to greater than 100 ps through the change in the shape of the 2D spectrum with time (spectral diffusion). At the high GuHCl concentration (5.1 M), at which Ht-M61A is essentially fully denatured as judged by CD, a very large reduction in dynamics is observed compared to the native protein within the approximately 100 ps time window of the experiment. The results suggest the denatured protein may be in a glassy-like state involving hydrophobic collapse around the heme.
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Affiliation(s)
- Seongheun Kim
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - Jean K. Chung
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - Kyungwon Kwak
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - Sarah E. J. Bowman
- Department of Chemistry, University of Rochester, Rochester, NY 14627-0216
| | - Kara L. Bren
- Department of Chemistry, University of Rochester, Rochester, NY 14627-0216
| | - Biman Bagchi
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - M. D. Fayer
- Department of Chemistry, Stanford University, Stanford, CA 94305
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Chen E, Van Vranken V, Kliger DS. The Folding Kinetics of the SDS-Induced Molten Globule Form of Reduced Cytochrome c. Biochemistry 2008; 47:5450-9. [DOI: 10.1021/bi702452u] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eefei Chen
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064
| | - Vanessa Van Vranken
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064
| | - David S. Kliger
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064
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Ye M, Zhang QL, Li H, Weng YX, Wang WC, Qiu XG. Infrared spectroscopic discrimination between the loop and alpha-helices and determination of the loop diffusion kinetics by temperature-jump time-resolved infrared spectroscopy for cytochrome c. Biophys J 2007; 93:2756-66. [PMID: 17557782 PMCID: PMC1989712 DOI: 10.1529/biophysj.107.106799] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The infrared (IR) absorption of the amide I band for the loop structure may overlap with that of the alpha-helices, which can lead to the misassignment of the protein secondary structures. A resolution-enhanced Fourier transform infrared (FTIR) spectroscopic method and temperature-jump (T-jump) time-resolved IR absorbance difference spectra were used to identify one specific loop absorption from the helical IR absorption bands of horse heart cytochrome c in D2O at a pD around 7.0. This small loop consists of residues 70-85 with Met-80 binding to the heme Fe(III). The FTIR spectra in amide I' region indicate that the loop and the helical absorption bands overlap at 1653 cm(-1) at room temperature. Thermal titration of the amide I' intensity at 1653 cm(-1) reveals that a transition in loop structural change occurs at lower temperature (Tm=45 degrees C), well before the global unfolding of the secondary structure (Tm approximately 82 degrees C). This loop structural change is assigned as being triggered by the Met-80 deligation from the heme Fe(III). T-jump time-resolved IR absorbance difference spectra reveal that a T-jump from 25 degrees C to 35 degrees C breaks the Fe-S bond between the Met-80 and the iron reversibly, which leads to a loop (1653 cm(-1), overlap with the helical absorption) to random coil (1645 cm(-1)) transition. The observed unfolding rate constant interpreted as the intrachain diffusion rate for this 16 residue loop was approximately 3.6x10(6) s(-1).
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Affiliation(s)
- Manping Ye
- Laboratory of Soft Matter Physics, Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China
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Plattner H, Hentschel J. Sub-second cellular dynamics: time-resolved electron microscopy and functional correlation. INTERNATIONAL REVIEW OF CYTOLOGY 2006; 255:133-76. [PMID: 17178466 DOI: 10.1016/s0074-7696(06)55003-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Subcellular processes, from molecular events to organellar responses and cell movement, cover a broad scale in time and space. Clearly the extremes, such as ion channel activation are accessible only by electrophysiology, whereas numerous routine methods exist for relatively slow processes. However, many other processes, from a millisecond time scale on, can be "caught" only by methods providing appropriate time resolution. Fast freezing (cryofixation) is the method of choice in that case. In combination with follow-up methodologies appropriate for electron microscopic (EM) analysis, with all its variations, such technologies can also provide high spatial resolution. Such analyses may include, for example, freeze-fracturing for analyzing restructuring of membrane components, scanning EM and other standard EM techniques, as well as analytical EM analyses. The latter encompass energy-dispersive x-ray microanalysis and electron spectroscopic imaging, all applicable, for instance, to the second messenger, calcium. Most importantly, when conducted in parallel, such analyses can provide a structural background to the functional analyses, such as cyclic nucleotide formation or protein de- or rephosphorylation during cell stimulation. In sum, we discuss many examples of how it is practically possible to achieve strict function-structure correlations in the sub-second time range. We complement this review by discussing alternative methods currently available to analyze fast cellular phenomena occurring in the sub-second time range.
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Affiliation(s)
- Helmut Plattner
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
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