1
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Joy A, Biswas R. Significance of the Disulfide Bridge in the Structure and Stability of Metalloprotein Azurin. J Phys Chem B 2024; 128:973-984. [PMID: 38236012 DOI: 10.1021/acs.jpcb.3c07089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Metalloproteins make up a class of proteins that incorporate metal ions into their structures, enabling them to perform essential functions in biological systems, such as catalysis and electron transport. Azurin is one such metalloprotein with copper cofactor, having a β-barrel structure with exceptional thermal stability. The copper metal ion is coordinated at one end of the β-barrel structure, and there is a disulfide bond at the opposite end. In this study, we explore the effect of this disulfide bond in the high thermal stability of azurin by analyzing both the native S-S bonded and S-S nonbonded (S-S open) forms using temperature replica exchange molecular dynamics (REMD). Similar to experimental observations, we find a 35 K decrease in denaturation temperature for S-S open azurin compared to that of the native holo form (420 K). As observed in the case of native holo azurin, the unfolding process of the S-S open form also started with disruptions of the α-helix. The free energy surfaces of the unfolding process revealed that the denaturation event of the S-S open form progresses through different sets of conformational ensembles. Subsequently, we compared the stabilities of individual β-sheet strands of both the S-S bonded and the S-S nonbonded forms of azurin. Further, we examined the contacts between individual residues for the central structures from the free energy surfaces of the S-S nonbonded form. The microscopic origin of the lowering in the denaturation temperature is further supplemented by thermodynamic analysis.
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Affiliation(s)
- Albin Joy
- Department of Chemistry, Indian Institute of Technology Tirupati, Yerpedu, Tirupati, Andhra Pradesh, India 517619
| | - Rajib Biswas
- Department of Chemistry, Indian Institute of Technology Tirupati, Yerpedu, Tirupati, Andhra Pradesh, India 517619
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2
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Abstract
Metal cofactors are critical centers for different biochemical processes of metalloproteins, and often, this metal coordination renders additional structural stability. In this study, we explore the additional stability conferred by the copper ion on azurin by analyzing both the apo and holo forms using temperature replica exchange molecular dynamics (REMD) data. We find a 14 K decrease in denaturation temperature for apo (406 K) azurin relative to that of holo (420 K), indicating a copper ion-induced additional thermal stability for holo azurin. The unfolding of apo azurin begins with the melting of α-helix and β-sheet V, similar to that of holo form. β-Sheets IV, VII, and VIII are comparatively more stable than other β-strands and melt at higher temperatures. Similar to holo azurin, the strong hydrophobic interactions among the apolar residues in the protein core is the key factor that renders high stability to apo protein as well. We construct free energy surfaces at different temperatures to capture the major conformations along the unfolding basins of the protein. Using contact maps from different basins we show the changes in the interaction between different residues along the unfolding pathway. Furthermore, we compare the Cα root-mean-square fluctuations (Cα-RMSF) and B-factor of all residues of apo and holo forms to understand the flexibility of different regions. The concerted displacement of α-helix and β-sheets V and VI from the protein core is another distinction we observe for apo compared to the holo form, where β-sheet VI was relatively stable.
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Affiliation(s)
- Albin Joy
- Department of Chemistry, Indian Institute of Technology Tirupati, Yerpedu 517619, Andhra Pradesh, India
| | - Rajib Biswas
- Department of Chemistry and Center for Atomic, Molecular and Optical Sciences & Technologies, Indian Institute of Technology Tirupati, Yerpedu 517619, Andhra Pradesh, India
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3
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Effects of hydrophobic solute on water normal modes. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2021.111303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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4
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Reddy KD, Biswas R. Theoretical spectroscopy of isotopically dilute water and hydrophobicity. J Chem Phys 2020; 153:094501. [DOI: 10.1063/5.0018401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Affiliation(s)
- Kambham Devendra Reddy
- Department of Chemistry and Center for Atomic, Molecular and Optical Sciences & Technologies, Indian Institute of Technology Tirupati, Yerpedu 517619, Andhra Pradesh, India
| | - Rajib Biswas
- Department of Chemistry and Center for Atomic, Molecular and Optical Sciences & Technologies, Indian Institute of Technology Tirupati, Yerpedu 517619, Andhra Pradesh, India
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5
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Imandi V, Chatterjee A. Estimating Arrhenius parameters using temperature programmed molecular dynamics. J Chem Phys 2016; 145:034104. [DOI: 10.1063/1.4958834] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Venkataramana Imandi
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Abhijit Chatterjee
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
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6
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Odagiri K, Seki K. Coil–globule transition of a polymer involved in excluded-volume interactions with macromolecules. J Chem Phys 2015; 143:134903. [DOI: 10.1063/1.4932344] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Kenta Odagiri
- School of Network and Information, Senshu University, Kawasaki 214-8580, Japan
| | - Kazuhiko Seki
- National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, Tsukuba, Ibaraki 305-8565, Japan
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7
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Ahalawat N, Arora S, Murarka RK. Structural Ensemble of CD4 Cytoplasmic Tail (402–419) Reveals a Nearly Flat Free-Energy Landscape with Local α-Helical Order in Aqueous Solution. J Phys Chem B 2015; 119:11229-42. [DOI: 10.1021/acs.jpcb.5b03092] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Navjeet Ahalawat
- Department
of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
| | - Simran Arora
- Department
of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
| | - Rajesh K. Murarka
- Department
of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
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8
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Duan LL, Zhu T, Zhang QG, Tang B, Zhang JZH. Electronic polarization stabilizes tertiary structure prediction of HP-36. J Mol Model 2014; 20:2195. [PMID: 24715046 PMCID: PMC3996369 DOI: 10.1007/s00894-014-2195-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 03/02/2014] [Indexed: 01/10/2023]
Abstract
Molecular dynamic (MD) simulations with both implicit and explicit solvent models have been carried out to study the folding dynamics of HP-36 protein. Starting from the extended conformation, the secondary structure of all three helices in HP-36 was formed in about 50 ns and remained stable in the remaining simulation. However, the formation of the tertiary structure was difficult. Although some intermediates were close to the native structure, the overall conformation was not stable. Further analysis revealed that the large structure fluctuation of loop and hydrophobic core regions was devoted mostly to the instability of the structure during MD simulation. The backbone root-mean-square deviation (RMSD) of the loop and hydrophobic core regions showed strong correlation with the backbone RMSD of the whole protein. The free energy landscape indicated that the distribution of main chain torsions in loop and turn regions was far away from the native state. Starting from an intermediate structure extracted from the initial AMBER simulation, HP-36 was found to generally fold to the native state under the dynamically adjusted polarized protein-specific charge (DPPC) simulation, while the peptide did not fold into the native structure when AMBER force filed was used. The two best folded structures were extracted and taken into further simulations in water employing AMBER03 charge and DPPC for 25 ns. Result showed that introducing polarization effect into interacting potential could stabilize the near-native protein structure.
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Affiliation(s)
- Li L Duan
- College of Physics and Electronics, Shandong Normal University, Jinan, 250014, China
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9
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Ghosh R, Roy S, Bagchi B. Solvent Sensitivity of Protein Unfolding: Dynamical Study of Chicken Villin Headpiece Subdomain in Water–Ethanol Binary Mixture. J Phys Chem B 2013; 117:15625-38. [DOI: 10.1021/jp406255z] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Rikhia Ghosh
- Solid State and Structural
Chemistry Unit, Indian Institute of Science, C. V. Raman Avenue, Bangalore 560012, India
| | - Susmita Roy
- Solid State and Structural
Chemistry Unit, Indian Institute of Science, C. V. Raman Avenue, Bangalore 560012, India
| | - Biman Bagchi
- Solid State and Structural
Chemistry Unit, Indian Institute of Science, C. V. Raman Avenue, Bangalore 560012, India
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10
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Roy S, Bagchi B. Chemical Unfolding of Chicken Villin Headpiece in Aqueous Dimethyl Sulfoxide Solution: Cosolvent Concentration Dependence, Pathway, and Microscopic Mechanism. J Phys Chem B 2012; 117:4488-502. [DOI: 10.1021/jp308589b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Susmita Roy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore
560012, India
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore
560012, India
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11
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Roy S, Banerjee S, Biyani N, Jana B, Bagchi B. Theoretical and Computational Analysis of Static and Dynamic Anomalies in Water−DMSO Binary Mixture at Low DMSO Concentrations. J Phys Chem B 2010; 115:685-92. [DOI: 10.1021/jp109622h] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Susmita Roy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Saikat Banerjee
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Nikhil Biyani
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Biman Jana
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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12
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Banerjee S, Roy S, Bagchi B. Enhanced Pair Hydrophobicity in the Water−Dimethylsulfoxide (DMSO) Binary Mixture at Low DMSO Concentrations. J Phys Chem B 2010; 114:12875-82. [DOI: 10.1021/jp1045645] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Saikat Banerjee
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Susmita Roy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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13
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Saini S, Srinivas G, Bagchi B. Distance and Orientation Dependence of Excitation Energy Transfer: From Molecular Systems to Metal Nanoparticles. J Phys Chem B 2009; 113:1817-32. [DOI: 10.1021/jp806536w] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sangeeta Saini
- SSCU, Indian Institute of Science, Bangalore 560012, India, and IBM Almaden Research Center, San Jose, California 95120
| | - Goundla Srinivas
- SSCU, Indian Institute of Science, Bangalore 560012, India, and IBM Almaden Research Center, San Jose, California 95120
| | - Biman Bagchi
- SSCU, Indian Institute of Science, Bangalore 560012, India, and IBM Almaden Research Center, San Jose, California 95120
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14
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Sonavane UB, Ramadugu SK, Joshi RR. Study of Early Events in the Protein Folding of Villin Headpiece using Molecular Dynamics Simulation. J Biomol Struct Dyn 2008; 26:203-14. [DOI: 10.1080/07391102.2008.10507236] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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15
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Abstract
The folding of a protein is studied as it grows residue by residue from the N-terminus and enters an environment that stabilizes the folded state. This mode of folding of a growing chain is different from refolding where the full chain folds from a disordered initial configuration to the native state. We propose a sequential dynamic optimization method that computes the evolution of optimum folding pathways as amino acid residues are added to the peptide chain one by one. The dynamic optimization formulation is deterministic and uses Newton's equations of motion and a Go-type potential that establishes the native contacts and excluded volume effects. The method predicts the optimal energy-minimizing path among all the alternative feasible pathways. As two examples, the folding of the chicken villin headpiece, a 36-residue protein, and chymotrypsin inhibitor 2 (CI2), a 64-residue protein, are studied. Results on the villin headpiece show significant differences from the refolding of the same chain studied previously. Results on CI2 mostly agree with the results of refolding experiments and computational work.
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Affiliation(s)
- Serife Senturk
- College of Engineering, Koc University, Sariyer 34450 Istanbul, Turkey
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16
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Jang S, Sreerama N, Liao VHC, Lu SHF, Li FY, Shin S, Woody RW, Lin SH. Theoretical investigation of the photoinitiated folding of HP-36. Protein Sci 2006; 15:2290-9. [PMID: 16963648 PMCID: PMC2242384 DOI: 10.1110/ps.062145106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2006] [Revised: 06/22/2006] [Accepted: 06/24/2006] [Indexed: 10/24/2022]
Abstract
A computational model was developed to examine the phototriggered folding of a caged protein, a protein modified with an organic photolabile cross-linker. Molecular dynamics simulations of the modified 36-residue fragment of subdomain B of chicken villin head piece with a photolabile linker were performed, starting from both the caged and the uncaged structures. Construction of a free-energy landscape, based on principal components as well as on radius of gyration versus root-mean-square deviation, and circular dichroism calculations were employed to characterize folding behavior and structures. The folded structures observed in the molecular dynamics trajectories were found to be similar to that of the wild-type protein, in agreement with the published experimental results. The free-energy landscapes of the modified and wild-type proteins have similar topology, suggesting common thermodynamic/kinetic behavior. The existence of small differences in the free-energy surface of the modified protein from that of the native protein, however, indicates subtle differences in the folding behavior.
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Affiliation(s)
- Soonmin Jang
- Department of Applied Chemistry, Sejong University, Seoul 143-747, Korea
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17
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Mukherjee A, Bagchi B. Contact pair dynamics during folding of two small proteins: chicken villin head piece and the Alzheimer protein beta-amyloid. J Chem Phys 2006; 120:1602-12. [PMID: 15268287 DOI: 10.1063/1.1633253] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The folding of an extended protein to its unique native state requires establishment of specific, predetermined, often distant, contacts between amino acid residue pairs. The dynamics of contact pair formation between various hydrophobic residues during folding of two different small proteins, the chicken villin head piece (HP-36) and the Alzheimer protein beta-amyloid (betaA-40), are investigated by Brownian dynamics (BD) simulations. These two proteins represent two very different classes-HP-36 being globular while betaA-40 is nonglobular, stringlike. Hydropathy scale and nonlocal helix propensity of amino acids are used to model the complex interaction potential among the various amino acid residues. The minimalistic model we use here employs a connected backbone chain of atoms of equal size while an amino acid is attached to each backbone atom as an additional atom of differing sizes and interaction parameters, determined by the characteristics of each amino acid. Even for such simple models, we find that the low-energy structures obtained by BD simulations of both the model proteins mimic the native state of the real protein rather well, with a best root-mean-square deviation of 4.5 A for HP-36. For betaA-40 (where a single well-defined structure is not available), the simulated structures resemble the reported ensemble rather well, with the well-known beta-bend correctly reproduced. We introduce and calculate a contact pair distance time correlation function, C(P) (ij)(t), to quantify the dynamical evolution of the pair contact formation between the amino acid residue pairs i and j. The contact pair time correlation function exhibits multistage dynamics, including a two stage fast collapse, followed by a slow (microsecond long) late stage dynamics for several specific pairs. The slow late stage dynamics is in accordance with the findings of Sali et al. Analysis of the individual trajectories shows that the slow decay is due to the attempt of the protein to form energetically more favorable pair contacts to replace the less favorable ones. This late stage contact formation is a highly cooperative process, involving participation of several pairs and thus entropically unfavorable and expected to face a large free energy barrier. This is because any new pair contact formation among hydrophobic pairs will require breaking of several contacts, before the favorable ones can be formed. This aspect of protein folding dynamics is similar to relaxation in glassy liquids, where also alpha relaxation requires highly cooperative process of hopping. The present analysis suggests that waiting time for the necessary pair contact formation may obey the Poissonian distribution. We also study the dynamics of Forster energy transfer during folding between two tagged amino acid pairs. This dynamics can be studied by fluorescence resonance energy transfer (FRET). It is found that suitably placed donor-acceptor pairs can capture the slow dynamics during folding. The dynamics probed by FRET is predicted to be nonexponential.
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Affiliation(s)
- Arnab Mukherjee
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, India 560 012
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18
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Abstract
How fast can a protein possibly fold? This question has stimulated experimentalists to seek fast folding proteins and to engineer them to fold even faster. Proteins folding at or near the speed limit are prime candidates for all-atom molecular dynamics simulations. They may also have no free energy barrier, allowing the direct observation of intermediate structures on the pathways from the unfolded to the folded state. Both experimental and theoretical approaches predict a speed limit of approximately N/100micros for a generic N-residue single-domain protein, with alpha proteins folding faster than beta or alphabeta. The predicted limits suggest that most known ultrafast folding proteins can be engineered to fold more than ten times faster.
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Affiliation(s)
- Jan Kubelka
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Building 5, Room 104, Bethesda, MD 20892-0520, USA
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19
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Jang S, Kim E, Shin S, Pak Y. Ab Initio Folding of Helix Bundle Proteins Using Molecular Dynamics Simulations. J Am Chem Soc 2003; 125:14841-6. [PMID: 14640661 DOI: 10.1021/ja034701i] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have demonstrated that ab initio fast folding simulations at 400 K using a GB implicit solvent model with an all-atom based force field can describe the spontaneous formation of nativelike structures for the 36-residue villin headpiece and the 46-residue fragment B of Staphylococcal protein A. An implicit solvent model combined with high-temperature MD makes it possible to perform direct folding simulations of small- to medium-sized proteins by reducing the computational requirements tremendously. In the early stage of folding of the villin headpiece and protein A, initial hydrophobic collapse and rapid formation of helices were found to play important roles. For protein A, the third helix forms first in the early stage of folding and exhibits higher stability. The free energy profiles calculated from the folding simulations suggested that both of the helix-bundle proteins show a two-state thermodynamic behavior and protein A exhibits rather broad native basins.
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Affiliation(s)
- Soonmin Jang
- School of Chemistry, Seoul National University, Seoul 151-747, Korea
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20
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Srinivas G, Bagchi B. Study of Pair Contact Formation among Hydrophobic Residues in a Model HP-36 Protein: Relationship between Contact Order Parameter and Rate of Folding and Collapse. J Phys Chem B 2003. [DOI: 10.1021/jp022333j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Goundla Srinivas
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, India 560 012
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, India 560 012
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21
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Mukherjee A, Bagchi B. Probing folding free energy landscape of small proteins through minimalistic models: Folding of HP-36 and β-amyloid. J CHEM SCI 2003. [DOI: 10.1007/bf02708253] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Abstract
We have used laser temperature-jump to investigate the kinetics and mechanism of folding the 35 residue subdomain of the villin headpiece. The relaxation kinetics are biphasic with a sub-microsecond phase corresponding to a helix-coil transition and a slower microsecond phase corresponding to overall unfolding/refolding. At 300 K, the folding time is 4.3(+/-0.6) micros, making it the fastest folding, naturally occurring protein, with a rate close to the theoretical speed limit. This time is in remarkable agreement with the prediction of 5 (+11,-3) micros by Zagrovic et al. from atomistic molecular dynamics simulations using an implicit solvent model. We test their prediction that replacement of the C-terminal phenylalanine residue with alanine will increase the folding rate by removing a transient non-native interaction. We find that the alanine substitution has no effect on the folding rate or on the equilibrium constant. Implications of this result for the validity of the simulated folding mechanism are discussed.
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Affiliation(s)
- Jan Kubelka
- Laboratory of Chemical Physics, Building 5, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, MSC 0520, Bethesda, MD 20892-0520, USA
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23
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Mukherjee A, Bagchi B. Correlation between rate of folding, energy landscape, and topology in the folding of a model protein HP-36. J Chem Phys 2003. [DOI: 10.1063/1.1542599] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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