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Tavili E, Aziziyan F, Dabirmanesh B. Pathways of amyloid fibril formation and protein aggregation. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2024; 206:11-54. [PMID: 38811078 DOI: 10.1016/bs.pmbts.2024.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
The main cause of many neurodegenerative diseases and systemic amyloidoses is protein and peptide aggregation and the formation of amyloid fibrils. The study of aggregation mechanisms, the discovery and description of aggregate structures, and a comprehensive understanding of the molecular mechanisms of amyloid formation are of great importance for the diagnostic processes at the molecular level and for the development of therapeutic strategies to counter aggregation-associated disorders. Given that understanding protein misfolding phenomena is directly related to the protein folding process, we will briefly explain the protein folding mechanism and then discuss the important factors involved in protein aggregation. In the following, we review different mechanisms of amyloid formation and finally represent the current knowledge on how amyloid fibrils are formed based on kinetic and thermodynamic factors.
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Affiliation(s)
- Elaheh Tavili
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Fatemeh Aziziyan
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Bahareh Dabirmanesh
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
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2
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Lang L, Frontera A, Perez A, Bauzá A. Computational Study of Driving Forces in ATSP, PDIQ, and P53 Peptide Binding: C═O···C═O Tetrel Bonding Interactions at Work. J Chem Inf Model 2023; 63:3018-3029. [PMID: 37014944 PMCID: PMC10207270 DOI: 10.1021/acs.jcim.3c00024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Indexed: 04/06/2023]
Abstract
Understanding the molecular interactions that drive peptide folding is crucial to chemistry and biology. In this study, we analyzed the role of CO···CO tetrel bonding (TtB) interactions in the folding mechanism of three different peptides (ATSP, pDIQ, and p53), which exhibit a different propensity to fold in an α helix motif. To achieve this goal, we used both a recently developed Bayesian inference approach (MELDxMD) and Quantum Mechanics (QM) calculations at the RI-MP2/def2-TZVP level of theory. These techniques allowed us to study the folding process and to evaluate the strength of the CO···CO TtBs as well as the synergies between TtBs and hydrogen-bonding (HB) interactions. We believe that the results derived from our study will be helpful for those scientists working in computational biology, peptide chemistry, and structural biology.
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Affiliation(s)
- Lijun Lang
- Chemistry
Department, University of Florida, Gainesville, Florida 32611, United States
| | - Antonio Frontera
- Department
of Chemistry, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma, Baleares, Spain
| | - Alberto Perez
- Chemistry
Department, University of Florida, Gainesville, Florida 32611, United States
| | - Antonio Bauzá
- Department
of Chemistry, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma, Baleares, Spain
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3
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Holmes SG, Nagarajan B, Desai UR. 3- O-Sulfation induces sequence-specific compact topologies in heparan sulfate that encode a dynamic sulfation code. Comput Struct Biotechnol J 2022; 20:3884-3898. [PMID: 35891779 PMCID: PMC9309406 DOI: 10.1016/j.csbj.2022.07.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/05/2022] [Accepted: 07/05/2022] [Indexed: 11/17/2022] Open
Abstract
Heparan sulfate (HS) is arguably the most diverse linear biopolymer that is known to modulate hundreds of proteins. Whereas the configurational and conformational diversity of HS is well established in terms of varying sulfation patterns and iduronic acid (IdoA) puckers, a linear helical topology resembling a cylindrical rod is the only topology thought to be occupied by the biopolymer. We reasoned that 3-O-sulfation, a rare modification in natural HS, may induce novel topologies that contribute to selective recognition of proteins. In this work, we studied a library of 24 distinct HS hexasaccharides using molecular dynamics (MD). We discovered novel compact (C) topologies that are populated significantly by a unique group of 3-O-sulfated sequences containing IdoA residues. 3-O-sulfated sequences containing glucuronic acid (GlcA) residue and sequences devoid of 3-O-sulfate groups did not exhibit high levels of the C topology and primarily exhibited only the canonical linear (L) form. The C topology arises under dynamical conditions due to rotation around an IdoA → GlcN glycosidic linkage, especially in psi (Ψ) torsion. At an atomistic level, the L → C transformation is a multi-factorial phenomenon engineered to reduce like-charge repulsion, release one or more HS-bound water molecules, and organize a bi-dentate "IdoA-cation-IdoA" interaction. These forces also drive an L → C transformation in a 3-O-sulfated octasaccharide, which has shown evidence of the unique C topology in the co-crystallized state. The 3-O-sulfate-based generation of unique, sequence-specific, compact topologies indicate that natural HS encodes a dynamic sulfation code that could be exploited for selective recognition of target proteins.
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Affiliation(s)
- Samuel G. Holmes
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Balaji Nagarajan
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Umesh R. Desai
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
- Corresponding author at: Institute for Structural Biology, Drug Discovery, and Development, 800 E. Leigh Street, Suite 212, Richmond, VA 23219, USA.
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4
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Agarwal S, Smith M, De La Rosa I, Verba KA, Swartz P, Segura-Totten M, Mattos C. Development of a structure-analysis pipeline using multiple-solvent crystal structures of barrier-to-autointegration factor. Acta Crystallogr D Struct Biol 2020; 76:1001-1014. [DOI: 10.1107/s2059798320011341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 08/18/2020] [Indexed: 11/10/2022] Open
Abstract
The multiple-solvent crystal structure (MSCS) approach uses high concentrations of organic solvents to characterize the interactions and effects of solvents on proteins. Here, the method has been further developed and an MSCS data-handling pipeline is presented that uses the Detection of Related Solvent Positions (DRoP) program to improve data quality. DRoP is used to selectively model conserved water molecules, so that an advanced stage of structural refinement is reached quickly. This allows the placement of organic molecules more accurately and convergence on high-quality maps and structures. This pipeline was applied to the chromatin-associated protein barrier-to-autointegration factor (BAF), resulting in structural models with better than average statistics. DRoP and Phenix Structure Comparison were used to characterize the data sets and to identify a binding site that overlaps with the interaction site of BAF with emerin. The conserved water-mediated networks identified by DRoP suggested a mechanism by which water molecules are used to drive the binding of DNA. Normalized and differential B-factor analysis is shown to be a valuable tool to characterize the effects of specific solvents on defined regions of BAF. Specific solvents are identified that cause stabilization of functionally important regions of the protein. This work presents tools and a standardized approach for the analysis and comprehension of MSCS data sets.
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5
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Kearney BM, Schwabe M, Marcus KC, Roberts DM, Dechene M, Swartz P, Mattos C. DRoP: Automated detection of conserved solvent-binding sites on proteins. Proteins 2019; 88:152-165. [PMID: 31294888 DOI: 10.1002/prot.25781] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 06/19/2019] [Accepted: 07/06/2019] [Indexed: 11/08/2022]
Abstract
Water and ligand binding play critical roles in the structure and function of proteins, yet their binding sites and significance are difficult to predict a priori. Multiple solvent crystal structures (MSCS) is a method where several X-ray crystal structures are solved, each in a unique solvent environment, with organic molecules that serve as probes of the protein surface for sites evolved to bind ligands, while the first hydration shell is essentially maintained. When superimposed, these structures contain a vast amount of information regarding hot spots of protein-protein or protein-ligand interactions, as well as conserved water-binding sites retained with the change in solvent properties. Optimized mining of this information requires reliable structural data and a consistent, objective analysis tool. Detection of related solvent positions (DRoP) was developed to automatically organize and rank the water or small organic molecule binding sites within a given set of structures. It is a flexible tool that can also be used in conserved water analysis given multiple structures of any protein independent of the MSCS method. The DRoP output is an HTML format list of the solvent sites ordered by conservation rank in its population within the set of structures, along with renumbered and recolored PDB files for visualization and facile analysis. Here, we present a previously unpublished set of MSCS structures of bovine pancreatic ribonuclease A (RNase A) and use it together with published structures to illustrate the capabilities of DRoP.
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Affiliation(s)
- Bradley M Kearney
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts.,Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, North Carolina
| | - Michael Schwabe
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts
| | - Kendra C Marcus
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts
| | - Daniel M Roberts
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, North Carolina
| | - Michelle Dechene
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, North Carolina
| | - Paul Swartz
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, North Carolina
| | - Carla Mattos
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts.,Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, North Carolina
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Bayat M, Gourabi H, khammari A, Ahmad F, Saboury AA. A comparative study of structure, stability and function of sc-tenecteplase in the presence of stabilizing osmolytes. J Biotechnol 2018; 280:1-10. [DOI: 10.1016/j.jbiotec.2018.05.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/17/2018] [Accepted: 05/24/2018] [Indexed: 01/29/2023]
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Yaacob N, Ahmad Kamarudin NH, Leow ATC, Salleh AB, Raja Abd Rahman RNZ, Mohamad Ali MS. The Role of Solvent-Accessible Leu-208 of Cold-Active Pseudomonas fluorescens Strain AMS8 Lipase in Interfacial Activation, Substrate Accessibility and Low-Molecular Weight Esterification in the Presence of Toluene. Molecules 2017; 22:E1312. [PMID: 28805665 PMCID: PMC6152135 DOI: 10.3390/molecules22081312] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 07/31/2017] [Accepted: 08/04/2017] [Indexed: 11/23/2022] Open
Abstract
The alkaline cold-active lipase from Pseudomonas fluorescens AMS8 undergoes major structural changes when reacted with hydrophobic organic solvents. In toluene, the AMS8 lipase catalytic region is exposed by the moving hydrophobic lid 2 (Glu-148 to Gly-167). Solvent-accessible surface area analysis revealed that Leu-208, which is located next to the nucleophilic Ser-207 has a focal function in influencing substrate accessibility and flexibility of the catalytic pocket. Based on molecular dynamic simulations, it was found that Leu-208 strongly facilitates the lid 2 opening via its side-chain. The KM and Kcat/KM of L208A mutant were substrate dependent as it preferred a smaller-chain ester (pNP-caprylate) as compared to medium (pNP-laurate) or long-chain (pNP-palmitate) esters. In esterification of ethyl hexanoate, L208A promotes a higher ester conversion rate at 20 °C but not at 30 °C, as a 27% decline was observed. Interestingly, the wild-type (WT) lipase's conversion rate was found to increase with a higher temperature. WT lipase AMS8 esterification was higher in toluene as compared to L208A. Hence, the results showed that Leu-208 of AMS8 lipase plays an important role in steering a broad range of substrates into its active site region by regulating the flexibility of this region. Leu-208 is therefore predicted to be crucial for its role in interfacial activation and catalysis in toluene.
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Affiliation(s)
- Norhayati Yaacob
- Enzyme Technology/Molecular Biomedicine Laboratory, Enzyme and Microbial Technology Research Centre, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Malaysia.
| | - Nor Hafizah Ahmad Kamarudin
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 Serdang, Malaysia.
| | - Adam Thean Chor Leow
- Enzyme and Microbial Technology Research Centre, Department of Cell Biology and Molecule, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia.
| | - Abu Bakar Salleh
- Enzyme and Microbial Technology Research Centre, Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia.
| | - Raja Noor Zaliha Raja Abd Rahman
- Enzyme and Microbial Technology Research Centre, Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia.
| | - Mohd Shukuri Mohamad Ali
- Enzyme and Microbial Technology Research Centre, Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia.
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8
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Groot CCM, Velikov KP, Bakker HJ. Structure and dynamics of water molecules confined in triglyceride oils. Phys Chem Chem Phys 2016; 18:29361-29368. [PMID: 27734039 DOI: 10.1039/c6cp05883c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Water molecules confined in triglyceride oil form specific hydrogen-bonded structures involving the oil carbonyl groups.
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Affiliation(s)
| | - Krassimir P. Velikov
- Unilever R&D
- 3133 AC Vlaardingen
- The Netherlands
- Soft Condensed Matter & Biophysics
- Utrecht University
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9
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Kearney BM, Johnson CW, Roberts DM, Swartz P, Mattos C. DRoP: a water analysis program identifies Ras-GTP-specific pathway of communication between membrane-interacting regions and the active site. J Mol Biol 2013; 426:611-29. [PMID: 24189050 DOI: 10.1016/j.jmb.2013.10.036] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 10/26/2013] [Accepted: 10/28/2013] [Indexed: 01/09/2023]
Abstract
Ras GTPase mediates several cellular signal transduction pathways and is found mutated in a large number of cancers. It is active in the GTP-bound state, where it interacts with effector proteins, and at rest in the GDP-bound state. The catalytic domain is tethered to the membrane, with which it interacts in a nucleotide-dependent manner. Here we present the program Detection of Related Solvent Positions (DRoP) for crystallographic water analysis on protein surfaces and use it to study Ras. DRoP reads and superimposes multiple Protein Data Bank coordinates, transfers symmetry-related water molecules to the position closest to the protein surface, and ranks the waters according to how well conserved and tightly clustered they are in the set of structures. Coloring according to this rank allows visualization of the results. The effector-binding region of Ras is hydrated with highly conserved water molecules at the interface between the P-loop, switch I, and switch II, as well as at the Raf-RBD binding pocket. Furthermore, we discovered a new conserved water-mediated H-bonding network present in Ras-GTP, but not in Ras-GDP, that links the nucleotide sensor residues R161 and R164 on helix 5 to the active site. The double mutant RasN85A/N86A, where the final link between helix 5 and the nucleotide is not possible, is a severely impaired enzyme, while the single mutant RasN86A, with partial connection to the active site, has a wild-type hydrolysis rate. DRoP was instrumental in determining the water-mediated connectivity networks that link two lobes of the catalytic domain in Ras.
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Affiliation(s)
- Bradley M Kearney
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA; Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Christian W Johnson
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA
| | - Daniel M Roberts
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Paul Swartz
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Carla Mattos
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA; Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA.
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10
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Liu S, Hu AD, Lin Z. Extensive Computational Study on Conformations of Microsolvated Leucine Complexes. CHINESE J CHEM PHYS 2012. [DOI: 10.1088/1674-0068/25/04/409-418] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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11
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Perticaroli S, Comez L, Paolantoni M, Sassi P, Lupi L, Fioretto D, Paciaroni A, Morresi A. Broadband depolarized light scattering study of diluted protein aqueous solutions. J Phys Chem B 2010; 114:8262-9. [PMID: 20509696 DOI: 10.1021/jp101896f] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A broadband depolarized light scattering (DLS) study is performed on diluted lysozyme aqueous solutions as a function of temperature and concentration. The dynamical susceptibility, obtained in a wide spectral range (0.6-36000 GHz) through the coupled use of interferometric and dispersive devices, is interpreted and compared with neutron scattering and Raman-induced optical Kerr-effect literature data, thus giving a general picture of relaxation phenomena. We show that the proposed approach represents a suitable tool for investigating the hydration dynamics of protein-water solutions. A detailed analysis of the quasi-elastic scattering region evidences the existence of two distinct relaxational processes at picosecond time scales. The fast process (fractions of picosecond) is attributed to bulk water dynamics, while the slow one (few picoseconds) is attributed to dynamical rearrangements of water molecules strongly influenced by the protein (hydration water). The retardation effect here estimated of about 6-7 can be regarded as a direct measure of the increased protein-water and water-water hydrogen bond stability of the water molecules within the protein hydration shell. Interestingly, a similar effect was previously observed on small hydrophilic sugar molecules. Moreover, backbone and side chains torsional motions of the protein in the 600-5300 GHz frequency range are found to be insensitive to thermal variations and to eventual changes occurring in the premelting zone.
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12
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Jorgensen L, Hostrup S, Moeller EH, Grohganz H. Recent trends in stabilising peptides and proteins in pharmaceutical formulation – considerations in the choice of excipients. Expert Opin Drug Deliv 2009; 6:1219-30. [DOI: 10.1517/17425240903199143] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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Gao B, Wyttenbach T, Bowers MT. Protonated Arginine and Protonated Lysine: Hydration and Its Effect on the Stability of Salt-Bridge Structures. J Phys Chem B 2009; 113:9995-10000. [DOI: 10.1021/jp903307h] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Bing Gao
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510
| | - Thomas Wyttenbach
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510
| | - Michael T. Bowers
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510
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Gao B, Wyttenbach T, Bowers MT. Hydration of Protonated Aromatic Amino Acids: Phenylalanine, Tryptophan, and Tyrosine. J Am Chem Soc 2009; 131:4695-701. [DOI: 10.1021/ja8085017] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Bing Gao
- Department of Chemistry and Biochemistry, University of Califormia, Santa Barbara, California 93106-9510
| | - Thomas Wyttenbach
- Department of Chemistry and Biochemistry, University of Califormia, Santa Barbara, California 93106-9510
| | - Michael T. Bowers
- Department of Chemistry and Biochemistry, University of Califormia, Santa Barbara, California 93106-9510
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A stringent test for hydrophobicity scales: two proteins with 88% sequence identity but different structure and function. Proc Natl Acad Sci U S A 2008; 105:9233-7. [PMID: 18591657 DOI: 10.1073/pnas.0803264105] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protein-protein interactions (protein functionalities) are mediated by water, which compacts individual proteins and promotes close and temporarily stable large-area protein-protein interfaces. In their classic article, Kyte and Doolittle (KD) concluded that the "simplicity and graphic nature of hydrophobicity scales make them very useful tools for the evaluation of protein structures." In practice, however, attempts to develop hydrophobicity scales (for example, compatible with classical force fields (CFF) in calculating the energetics of protein folding) have encountered many difficulties. Here, we suggest an entirely different approach based on the idea that proteins are self-organized networks, subject to evolving finite-scale criticality (like some network glasses). We test this proposal against two small proteins that are delicately balanced between alpha and alpha/beta structures, with different functions encoded with only 12% of their amino acids. This example explains why protein structure prediction is so challenging, and it provides a severe test for the accuracy and content of hydrophobicity scales. This method confirms KD's evaluation and at the same time suggests that protein structure, dynamics, and function can be best discussed without using CFF.
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