1
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Penkov NV. Peculiarities of the Dynamical Hydration Shell of Native Conformation Protein Using a Bovine Serum Albumin Example. APPLIED SPECTROSCOPY 2024:37028241261097. [PMID: 38881287 DOI: 10.1177/00037028241261097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
This paper describes an approach based on the method of terahertz time-domain spectroscopy, which allows the analysis of dynamical hydration shells of proteins with a thickness of 1-2 nm. Using the example of bovine serum albumin in three conformations, it is shown that the hydration shells of the protein are characterized by increased binding of water molecules in the primary hydration layers, and in more distant areas of hydration, on the contrary, the water structure is somewhat destroyed. The fraction of free or weakly bound molecules, usually observed in the structure of liquid water in hydration shells, become more numerous but its average binding is greater than in undisturbed water. The energy distribution of hydrogen bonds in hydration shells is narrowed compared to undisturbed water. All these manifestations of hydration are most pronounced for the native conformation of the protein. Also, the hydration shells of the native protein are characterized by a smaller number of hydrogen bonds and a tendency to decrease their average energy compared to non-native conformations. The fact of a pronounced peculiarity of the hydration shells of the protein in the native conformation has been noted for different proteins before. However, the methodological approach used in this work for the first time allowed this peculiarity to be described by specific parameters of the intermolecular structure and dynamics of water.
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Affiliation(s)
- Nikita V Penkov
- Institute of Cell Biophysics, Federal Research Center, Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences, Pushchino, Russia
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2
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Ren K, Cao X, Zheng L, Liu S, Li L, Cheng L, Tian T, Tong X, Wang H, Jiang L. Liposomes decorated with β-conglycinin and glycinin: Construction, structure and in vitro digestive stability. Int J Biol Macromol 2024; 269:131900. [PMID: 38677675 DOI: 10.1016/j.ijbiomac.2024.131900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 04/29/2024]
Abstract
Liposomes were modified with different proportions of β-conglycinin (7S) and glycinin (11S) to form Lip-7S and Lip-11S. The morphology, interaction and in vitro simulated digestion of liposomes were studied. The particle size of Lip-7S was smaller than that of Lip-11S. When the values of Lip-7S and Lip-11S were 1:1 and 1:0.75, respectively, the ζ-potential had the maximum absolute value and the dispersion of the system was good. The results of multispectral analysis showed that hydrogen-bond and hydrophobic interaction dominated protein-modified liposomes, the protein structure adsorbed on the surface of liposomes changed, the content of α-helix decreased, and the structure of protein-modified liposomes became denser. The surface hydrophobicity and micropolarity of liposomes decreased with the increase of protein ratio, and tended to be stable after Lip-7S (1:1) and Lip-11S (1:0.75). Differential scanning calorimetry showed that Lip-7S had higher phase transition temperature (≥170.5 °C) and better rigid structure. During simulated digestion, Lip-7S (22.5 %) released less Morin than Lip (40.6 %) and Lip-11S (26.2 %), and effectively delayed the release of FFAs. The environmental stability of liposomes was effectively improved by protein modification, and 7S had better modification effect than 11S. This provides a theoretical basis for 7S and 11S modified liposomes, and also provides a data reference for searching for new materials for stabilization of liposomes.
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Affiliation(s)
- Kunyu Ren
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China
| | - Xinru Cao
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China
| | - Lexi Zheng
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China
| | - Shi Liu
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China
| | - Lanxin Li
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China
| | - Lin Cheng
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China
| | - Tian Tian
- College of Food Science and Engineering, Hainan University, Haikou, Hainan 570228, China
| | - Xiaohong Tong
- College of Agricultural, Northeast Agricultural University, Harbin, Heilongjiang 150030, China.
| | - Huan Wang
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China.
| | - Lianzhou Jiang
- College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China
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3
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Škrbić T, Giacometti A, Hoang TX, Maritan A, Banavar JR. A Tale of Two Chains: Geometries of a Chain Model and Protein Native State Structures. Polymers (Basel) 2024; 16:502. [PMID: 38399880 PMCID: PMC10892082 DOI: 10.3390/polym16040502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/06/2024] [Accepted: 02/10/2024] [Indexed: 02/25/2024] Open
Abstract
Linear chain molecules play a central role in polymer physics with innumerable industrial applications. They are also ubiquitous constituents of living cells. Here, we highlight the similarities and differences between two distinct ways of viewing a linear chain. We do this, on the one hand, through the lens of simulations for a standard polymer chain of tethered spheres at low and high temperatures and, on the other hand, through published experimental data on an important class of biopolymers, proteins. We present detailed analyses of their local and non-local structures as well as the maps of their closest contacts. We seek to reconcile the startlingly different behaviors of the two types of chains based on symmetry considerations.
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Affiliation(s)
- Tatjana Škrbić
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30170 Venice, Italy;
- Department of Physics and Institute for Fundamental Science, University of Oregon, Eugene, OR 97403, USA;
| | - Achille Giacometti
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30170 Venice, Italy;
- European Centre for Living Technology (ECLT), Ca’ Bottacin, Dorsoduro 3911, Calle Crosera, 30123 Venice, Italy
| | - Trinh X. Hoang
- Institute of Physics, Vietnam Academy of Science and Technology, Hanoi 11108, Vietnam;
| | - Amos Maritan
- Department of Physics and Astronomy, University of Padua, 35122 Padua, Italy;
| | - Jayanth R. Banavar
- Department of Physics and Institute for Fundamental Science, University of Oregon, Eugene, OR 97403, USA;
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4
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El-Sawah AA, El-Naggar NEA, Eldegla HE, Soliman HM. Green synthesis of collagen nanoparticles by Streptomyces xinghaiensis NEAA-1, statistical optimization, characterization, and evaluation of their anticancer potential. Sci Rep 2024; 14:3283. [PMID: 38332176 PMCID: PMC10853202 DOI: 10.1038/s41598-024-53342-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/31/2024] [Indexed: 02/10/2024] Open
Abstract
Collagen nanoparticles (collagen-NPs) are promising biopolymeric nanoparticles due to their superior biodegradability and biocompatibility. The low immunogenicity and non-toxicity of collagen-NPs makes it preferable for a wide range of applications. A total of eight morphologically distinct actinomycetes strains were newly isolated from various soil samples in Egypt. The cell-free supernatants of these strains were tested for their ability. These strains' cell-free supernatants were tested for their ability to synthesize collagen-NPs. Five isolates had the ability to biosynthesize collagen-NPs. Among these, a potential culture, Streptomyces sp. NEAA-1, was chosen and identified as Streptomyces xinghaiensis NEAA-1 based on 16S rRNA sequence analysis as well as morphological, cultural and physiological properties. The sequence data has been deposited at the GenBank database under the accession No. OQ652077.1. Face-centered central composite design (FCCD) has been conducted to maximize collagen-NPs biosynthesis. Maximum collagen-NPs was 8.92 mg/mL under the condition of 10 mg/mL of collagen concentration, initial pH 7, incubation time of 48 h and temperature of 35 °C. The yield of collagen-NPs obtained via FCCD optimization (8.92 mg/mL) was 3.32-fold compared to the yield obtained under non-optimized conditions (2.5 mg/mL). TEM analysis of collagen-NPs showed hollow sphere nanoscale particles with mean of 32.63 ± 14.59 nm in diameter. FTIR spectra showed major peaks of amide I, amide II and amide III of collagen and also the cell-free supernatant involved in effective capping of collagen-NPs. The biosynthesized collagen-NPs exhibited anti-hemolytic, antioxidant and cytotoxic activities. The inhibitory concentrations (IC50) against MCF-7, HeP-G2 and HCT116 cell lines were 11.62 ± 0.8, 19.60 ± 1.2 and 41.67 ± 2.2 µg/mL; respectively. The in-vivo investigation showed that collagen-NPs can suppress Ehrlich ascites carcinoma (EAC) growth in mice. The collagen-NPs/DOX combination treatment showed considerable tumor growth suppression (95.58%). Collagen-NPs evaluated as nanocarrier with a chemotherapeutic agent, methotrexate (MTX). The average size of MTX loaded collagen-NPs was 42.73 ± 3.5 nm. Encapsulation efficiency percentage (EE %) was 48.91% and drug loading percentage (DL %) was 24.45%.
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Affiliation(s)
- Asmaa A El-Sawah
- Botany Department, Faculty of Science, Mansoura University, Mansoura, Egypt.
| | - Noura El-Ahmady El-Naggar
- Department of Bioprocess Development, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, 21934, Alexandria, Egypt.
| | - Heba E Eldegla
- Medical Microbiology and Immunology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Hoda M Soliman
- Botany Department, Faculty of Science, Mansoura University, Mansoura, Egypt
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5
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Galano‐Frutos JJ, Sancho J. Energy, water, and protein folding: A molecular dynamics-based quantitative inventory of molecular interactions and forces that make proteins stable. Protein Sci 2024; 33:e4905. [PMID: 38284492 PMCID: PMC10804899 DOI: 10.1002/pro.4905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 12/12/2023] [Accepted: 01/05/2024] [Indexed: 01/30/2024]
Abstract
Protein folding energetics can be determined experimentally on a case-by-case basis but it is not understood in sufficient detail to provide deep control in protein design. The fundamentals of protein stability have been outlined by calorimetry, protein engineering, and biophysical modeling, but these approaches still face great difficulty in elucidating the specific contributions of the intervening molecules and physical interactions. Recently, we have shown that the enthalpy and heat capacity changes associated to the protein folding reaction can be calculated within experimental error using molecular dynamics simulations of native protein structures and their corresponding unfolded ensembles. Analyzing in depth molecular dynamics simulations of four model proteins (CI2, barnase, SNase, and apoflavodoxin), we dissect here the energy contributions to ΔH (a key component of protein stability) made by the molecular players (polypeptide and solvent molecules) and physical interactions (electrostatic, van der Waals, and bonded) involved. Although the proteins analyzed differ in length, isoelectric point and fold class, their folding energetics is governed by the same quantitative pattern. Relative to the unfolded ensemble, the native conformations are enthalpically stabilized by comparable contributions from protein-protein and solvent-solvent interactions, and almost equally destabilized by interactions between protein and solvent molecules. The native protein surface seems to interact better with water than the unfolded one, but this is outweighed by the unfolded surface being larger. From the perspective of physical interactions, the native conformations are stabilized by van de Waals and Coulomb interactions and destabilized by conformational strain arising from bonded interactions. Also common to the four proteins, the sign of the heat capacity change is set by interactions between protein and solvent molecules or, from the alternative perspective, by Coulomb interactions.
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Affiliation(s)
- Juan José Galano‐Frutos
- Biocomputation and Complex Systems Physics Institute (BIFI)‐Joint Unit GBsC‐CSICUniversity of ZaragozaZaragozaSpain
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de CienciasUniversity of ZaragozaZaragozaSpain
| | - Javier Sancho
- Biocomputation and Complex Systems Physics Institute (BIFI)‐Joint Unit GBsC‐CSICUniversity of ZaragozaZaragozaSpain
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de CienciasUniversity of ZaragozaZaragozaSpain
- Aragon Health Research Institute (IIS Aragón)ZaragozaSpain
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6
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Acquasaliente L, Pierangelini A, Pagotto A, Pozzi N, De Filippis V. From haemadin to haemanorm: Synthesis and characterization of full-length haemadin from the leech Haemadipsa sylvestris and of a novel bivalent, highly potent thrombin inhibitor (haemanorm). Protein Sci 2023; 32:e4825. [PMID: 37924304 PMCID: PMC10683372 DOI: 10.1002/pro.4825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 10/25/2023] [Accepted: 10/27/2023] [Indexed: 11/06/2023]
Abstract
Hirudin from Hirudo medicinalis is a bivalent α-Thrombin (αT) inhibitor, targeting the enzyme active site and exosite-I, and is currently used in anticoagulant therapy along with its simplified analogue hirulog. Haemadin, a small protein (57 amino acids) isolated from the land-living leech Haemadipsa sylvestris, selectively inhibits αT with a potency identical to that of recombinant hirudin (KI = 0.2 pM), with which it shares a common disulfide topology and overall fold. At variance with hirudin, haemadin targets exosite-II and therefore (besides the free protease) it also blocks thrombomodulin-bound αT without inhibiting the active intermediate meizothrombin, thus offering potential advantages over hirudin. Here, we produced in reasonably high yields and pharmaceutical purity (>98%) wild-type haemadin and the oxidation resistant Met5 → nor-Leucine analogue, both inhibiting αT with a KI of 0.2 pM. Thereafter, we used site-directed mutagenesis, spectroscopic, ligand-displacement, and Hydrogen/Deuterium Exchange-Mass Spectrometry techniques to map the αT regions relevant for the interaction with full-length haemadin and with the synthetic N- and C-terminal peptides Haem(1-10) and Haem(45-57). Haem(1-10) competitively binds to/inhibits αT active site (KI = 1.9 μM) and its potency was enhanced by 10-fold after Phe3 → β-Naphthylalanine exchange. Conversely to full-length haemadin, haem(45-57) displays intrinsic affinity for exosite-I (KD = 1.6 μM). Hence, we synthesized a peptide in which the sequences 1-9 and 45-57 were joined together through a 3-Glycine spacer to yield haemanorm, a highly potent (KI = 0.8 nM) inhibitor targeting αT active site and exosite-I. Haemanorm can be regarded as a novel class of hirulog-like αT inhibitors with potential pharmacological applications.
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Affiliation(s)
- Laura Acquasaliente
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
| | - Andrea Pierangelini
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
| | - Anna Pagotto
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
| | - Nicola Pozzi
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
- Department of Biochemistry and Molecular Biology, Edward A. Doisy Research CenterSaint Louis UniversitySt. LouisMissouriUSA
| | - Vincenzo De Filippis
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
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7
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Chadda R, Lee T, Mahoney-Kruszka R, Kelley EG, Bernhardt N, Sandal P, Robertson JL. A thermodynamic analysis of CLC transporter dimerization in lipid bilayers. Proc Natl Acad Sci U S A 2023; 120:e2305100120. [PMID: 37788312 PMCID: PMC10576108 DOI: 10.1073/pnas.2305100120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 08/17/2023] [Indexed: 10/05/2023] Open
Abstract
The CLC-ec1 chloride/proton antiporter is a membrane-embedded homodimer with subunits that can dissociate and associate, but the thermodynamic driving forces favor the assembled dimer at biological densities. Yet, the physical reasons for this stability are confounding as dimerization occurs via the burial of hydrophobic interfaces away from the lipid solvent. For binding of nonpolar surfaces in aqueous solution, the driving force is often attributed to the hydrophobic effect, but this should not apply in the membrane since there is very little water. To investigate this further, we quantified the thermodynamic changes associated with CLC dimerization in membranes by carrying out a van 't Hoff analysis of the temperature dependency of the free energy of dimerization, ΔG°. To ensure that the reaction reached equilibrium at different temperatures, we utilized a Förster resonance energy transfer assay to report on relaxation kinetics of subunit exchange as a function of temperature. Equilibration times were then applied to measure CLC-ec1 dimerization isotherms at different temperatures using the single-molecule subunit-capture photobleaching analysis approach. The results demonstrate that the dimerization free energy of CLC in Escherichia coli-like membranes exhibits a nonlinear temperature dependency corresponding to a large, negative change in heat capacity, a signature of solvent ordering effects such as the hydrophobic effect. Consolidating this with our previous molecular analyses suggests that the nonbilayer defect required to solvate the monomeric state is one source of the observed change in heat capacity and indicates the existence of a generalizable driving force for protein association in membranes.
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Affiliation(s)
- Rahul Chadda
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO63110
| | - Taeho Lee
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO63110
- Department of Physics, Washington University, St. Louis, MO63130
| | - Robyn Mahoney-Kruszka
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO63110
| | - Elizabeth G. Kelley
- Center for Neutron Research, National Institute for Standards and Technology, Gaithersburg, MD20899
| | - Nathan Bernhardt
- Theoretical Molecular Biophysics Laboratory, National Heart, Lung and Blood Institute, NIH, Bethesda, MD20894
| | - Priyanka Sandal
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, IA52242
| | - Janice L. Robertson
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO63110
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8
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Penkov NV. Terahertz spectroscopy as a method for investigation of hydration shells of biomolecules. Biophys Rev 2023; 15:833-849. [PMID: 37974994 PMCID: PMC10643733 DOI: 10.1007/s12551-023-01131-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Accepted: 08/30/2023] [Indexed: 11/19/2023] Open
Abstract
The hydration of biomolecules is one of the fundamental processes underlying the construction of living matter. The formation of the native conformation of most biomolecules is possible only in an aqueous environment. At the same time, not only water affects the structure of biomolecules, but also biomolecules affect the structure of water, forming hydration shells. However, the study of the structure of biomolecules is given much more attention than their hydration shells. A real breakthrough in the study of hydration occurred with the development of the THz spectroscopy method, which showed that the hydration shell of biomolecules is not limited to 1-2 layers of strongly bound water, but also includes more distant areas of hydration with altered molecular dynamics. This review examines the fundamental features of the THz frequency range as a source of information about the structural and dynamic characteristics of water that change during hydration. The applied approaches to the study of hydration shells of biomolecules based on THz spectroscopy are described. The data on the hydration of biomolecules of all main types obtained from the beginning of the application of THz spectroscopy to the present are summarized. The emphasis is placed on the possible participation of extended hydration shells in the realization of the biological functions of biomolecules and at the same time on the insufficient knowledge of their structural and dynamic characteristics.
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Affiliation(s)
- Nikita V. Penkov
- Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences”, Institute of Cell Biophysics RAS, 142290 Pushchino, Russia
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9
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van der Sman R, van der Goot A. Hypotheses concerning structuring of extruded meat analogs. Curr Res Food Sci 2023; 6:100510. [PMID: 37275388 PMCID: PMC10236473 DOI: 10.1016/j.crfs.2023.100510] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 04/22/2023] [Accepted: 04/26/2023] [Indexed: 06/07/2023] Open
Abstract
In this paper, we review the physicochemical phenomena occurring during the structuring processes in the manufacturing of plant-based meat analogs via high-moisture-extrusion (HME). After the initial discussion on the input materials, we discuss the hypotheses behind the physics of the functional tasks that can be defined for HME. For these hypotheses, we have taken a broader view than only the scientific literature on plant-based meat analogs but incorporated also literature from soft matter physics and patent literature. Many of these hypotheses remain to be proven. Hence, we hope that this overview will inspire researchers to fill the still-open knowledge gaps concerning the multiscale structure of meat analogs.
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Affiliation(s)
- R.G.M. van der Sman
- Wageningen Food Biobased Research, the Netherlands
- Food Process Engineering, Wageningen University, the Netherlands
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10
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Seelig J, Seelig A. Protein Stability─Analysis of Heat and Cold Denaturation without and with Unfolding Models. J Phys Chem B 2023; 127:3352-3363. [PMID: 37040567 PMCID: PMC10123674 DOI: 10.1021/acs.jpcb.3c00882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Protein stability is important in many areas of life sciences. Thermal protein unfolding is investigated extensively with various spectroscopic techniques. The extraction of thermodynamic properties from these measurements requires the application of models. Differential scanning calorimetry (DSC) is less common, but is unique as it measures directly a thermodynamic property, that is, the heat capacity Cp(T). The analysis of Cp(T) is usually performed with the chemical equilibrium two-state model. This is not necessary and leads to incorrect thermodynamic consequences. Here we demonstrate a straightforward model-independent evaluation of heat capacity experiments in terms of protein unfolding enthalpy ΔH(T), entropy ΔS(T), and free energy ΔG(T)). This now allows the comparison of the experimental thermodynamic data with the predictions of different models. We critically examined the standard chemical equilibrium two-state model, which predicts a positive free energy for the native protein, and diverges distinctly from the experimental temperature profiles. We propose two new models which are equally applicable to spectroscopy and calorimetry. The ΘU(T)-weighted chemical equilibrium model and the statistical-mechanical two-state model provide excellent fits of the experimental data. They predict sigmoidal temperature profiles for enthalpy and entropy, and a trapezoidal temperature profile for the free energy. This is illustrated with experimental examples for heat and cold denaturation of lysozyme and β-lactoglobulin. We then show that the free energy is not a good criterion to judge protein stability. More useful parameters are discussed, including protein cooperativity. The new parameters are embedded in a well-defined thermodynamic context and are amenable to molecular dynamics calculations.
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Affiliation(s)
- Joachim Seelig
- Biozentrum, University of Basel, Spitalstrasse 41, CH-4056 Basel, Switzerland
| | - Anna Seelig
- Biozentrum, University of Basel, Spitalstrasse 41, CH-4056 Basel, Switzerland
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11
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Chadda R, Lee T, Sandal P, Mahoney-Kruszka R, Robertson JL. A thermodynamic analysis of CLC transporter dimerization in lipid bilayers. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532678. [PMID: 36993257 PMCID: PMC10055089 DOI: 10.1101/2023.03.14.532678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The CLC-ec1 chloride/proton antiporter is a membrane embedded homodimer where subunits can dissociate and associate, but the thermodynamic driving forces favor the assembled form at biological densities. Yet, the physical reasons for this stability are confounding since binding occurs via the burial of hydrophobic protein interfaces yet the hydrophobic effect should not apply since there is little water within the membrane. To investigate this further, we quantified the thermodynamic changes associated with CLC dimerization in membranes by carrying out a van 't Hoff analysis of the temperature dependency of the free energy of dimerization, ΔG° . To ensure that the reaction reached equilibrium under changing conditions, we utilized a Förster Resonance Energy Transfer based assay to report on the relaxation kinetics of subunit exchange as a function of temperature. These equilibration times were then applied to measure CLC-ec1 dimerization isotherms as a function of temperature using the single-molecule subunit-capture photobleaching analysis approach. The results demonstrate that the dimerization free energy of CLC in E. coli membranes exhibits a non-linear temperature dependency corresponding to a large, negative change in heat capacity, a signature of solvent ordering effects including the hydrophobic effect. Consolidating this with our previous molecular analyses suggests that the non-bilayer defect required to solvate the monomeric state is the molecular source of this large change in heat capacity and is a major and generalizable driving force for protein association in membranes.
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12
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Seelig J, Seelig A. Protein Unfolding—Thermodynamic Perspectives and Unfolding Models. Int J Mol Sci 2023; 24:ijms24065457. [PMID: 36982534 PMCID: PMC10049513 DOI: 10.3390/ijms24065457] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 03/14/2023] Open
Abstract
We review the key steps leading to an improved analysis of thermal protein unfolding. Thermal unfolding is a dynamic cooperative process with many short-lived intermediates. Protein unfolding has been measured by various spectroscopic techniques that reveal structural changes, and by differential scanning calorimetry (DSC) that provides the heat capacity change Cp(T). The corresponding temperature profiles of enthalpy ΔH(T), entropy ΔS(T), and free energy ΔG(T) have thus far been evaluated using a chemical equilibrium two-state model. Taking a different approach, we demonstrated that the temperature profiles of enthalpy ΔH(T), entropy ΔS(T), and free energy ΔG(T) can be obtained directly by a numerical integration of the heat capacity profile Cp(T). DSC thus offers the unique possibility to assess these parameters without resorting to a model. These experimental parameters now allow us to examine the predictions of different unfolding models. The standard two-state model fits the experimental heat capacity peak quite well. However, neither the enthalpy nor entropy profiles (predicted to be almost linear) are congruent with the measured sigmoidal temperature profiles, nor is the parabolic free energy profile congruent with the experimentally observed trapezoidal temperature profile. We introduce three new models, an empirical two-state model, a statistical–mechanical two-state model and a cooperative statistical-mechanical multistate model. The empirical model partially corrects for the deficits of the standard model. However, only the two statistical–mechanical models are thermodynamically consistent. The two-state models yield good fits for the enthalpy, entropy and free energy of unfolding of small proteins. The cooperative statistical–mechanical multistate model yields perfect fits, even for the unfolding of large proteins such as antibodies.
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13
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Mei Y, Jiang Y, Zhang Z, Zhang H. Muscle and bone characteristics of a Chinese family with spinal muscular atrophy, lower extremity predominant 1 (SMALED1) caused by a novel missense DYNC1H1 mutation. BMC Med Genomics 2023; 16:47. [PMID: 36882741 PMCID: PMC9990223 DOI: 10.1186/s12920-023-01472-4] [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: 11/09/2022] [Accepted: 02/27/2023] [Indexed: 03/09/2023] Open
Abstract
BACKGROUND Spinal muscular atrophy, lower extremity predominant (SMALED) is a type of non-5q spinal muscular atrophy characterised by weakness and atrophy of lower limb muscles without sensory abnormalities. SMALED1 can be caused by dynein cytoplasmic 1 heavy chain 1 (DYNC1H1) gene variants. However, the phenotype and genotype of SMALED1 may overlap with those of other neuromuscular diseases, making it difficult to diagnose clinically. Additionally, bone metabolism and bone mineral density (BMD) in patients with SMALED1 have never been reported. METHODS We investigated a Chinese family in which 5 individuals from 3 generations had lower limb muscle atrophy and foot deformities. Clinical manifestations and biochemical and radiographic indices were analysed, and mutational analysis was performed by whole-exome sequencing (WES) and Sanger sequencing. RESULTS A novel mutation in exon 4 of the DYNC1H1 gene (c.587T > C, p.Leu196Ser) was identified in the proband and his affected mother by WES. Sanger sequencing confirmed that the proband and 3 affected family members were carriers of this mutation. As leucine is a hydrophobic amino acid and serine is hydrophilic, the hydrophobic interaction resulting from mutation of amino acid residue 196 could influence the stability of the DYNC1H1 protein. Leg muscle magnetic resonance imaging of the proband revealed severe atrophy and fatty infiltration, and electromyographic recordings showed chronic neurogenic impairment of the lower extremities. Bone metabolism markers and BMD of the proband were all within normal ranges. None of the 4 patients had experienced fragility fractures. CONCLUSION This study identified a novel DYNC1H1 mutation and expands the spectrum of phenotypes and genotypes of DYNC1H1-related disorders. This is the first report of bone metabolism and BMD in patients with SMALED1.
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Affiliation(s)
- Yazhao Mei
- Shanghai Clinical Research Center of Bone Disease, Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200233, Shanghai, China
| | - Yunyi Jiang
- Shanghai Clinical Research Center of Bone Disease, Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200233, Shanghai, China
| | - Zhenlin Zhang
- Shanghai Clinical Research Center of Bone Disease, Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200233, Shanghai, China.
| | - Hao Zhang
- Shanghai Clinical Research Center of Bone Disease, Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200233, Shanghai, China.
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14
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Seal S, Banerjee N, Mahato R, Kundu T, Sinha D, Chakraborty T, Sinha D, Sau K, Chatterjee S, Sau S. Serine 106 preserves the tertiary structure, function, and stability of a cyclophilin from Staphylococcus aureus. J Biomol Struct Dyn 2023; 41:1479-1494. [PMID: 34967275 DOI: 10.1080/07391102.2021.2021992] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
SaCyp, a staphylococcal cyclophilin involved in both protein folding and pathogenesis, has a Ser residue at position 106 and a Trp residue at position 136. While Ser 106 of SaCyp aligned with a cyclosporin A (CsA) binding Ala residue, its Trp 136 aligned with a Trp or a Phe residue of most other cyclophilins. To demonstrate the exact roles of Ser 106 and Trp 136 in SaCyp, we have elaborately studied rCyp[S106A] and rCyp[W136A], two-point mutants of a recombinant SaCyp (rCyp) harboring an Ala substitution at positions 106 and 136, respectively. Of the mutants, rCyp[W136A] showed the rCyp-like CsA binding affinity and peptidyl-prolyl cis-trans isomerase (PPIase) activity. Conversely, the PPIase activity, CsA binding affinity, stability, tertiary structure, surface hydrophobicity, and Trp accessibility of rCyp[S106A] notably differed from those of rCyp. The computational experiments also reveal that the structure, dimension, and fluctuation of SaCyp are not identical to those of SaCyp[S106A]. Furthermore, Ser at position 106 of SaCyp, compared to Ala at the same position, formed a higher number of non-covalent bonds with CsA. Collectively, Ser 106 is an indispensable residue for SaCyp that keeps its tertiary structure, function, and stability intact.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Soham Seal
- Department of Biochemistry, Bose Institute, Kolkata, West Bengal, India
| | - Nilanjan Banerjee
- Department of Biophysics, Bose Institute, Kolkata, West Bengal, India
| | - Rohit Mahato
- Department of Biochemistry, Bose Institute, Kolkata, West Bengal, India
| | - Tanmoy Kundu
- Department of Biochemistry, Bose Institute, Kolkata, West Bengal, India
| | - Debabrata Sinha
- Department of Biochemistry, Bose Institute, Kolkata, West Bengal, India
| | | | - Debasmita Sinha
- Department of Biochemistry, Bose Institute, Kolkata, West Bengal, India
| | - Keya Sau
- Department of Biotechnology, Haldia Institute of Technology, Haldia, West Bengal, India
| | | | - Subrata Sau
- Department of Biochemistry, Bose Institute, Kolkata, West Bengal, India
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15
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Marasco R, Fusi M, Coscolín C, Barozzi A, Almendral D, Bargiela R, Nutschel CGN, Pfleger C, Dittrich J, Gohlke H, Matesanz R, Sanchez-Carrillo S, Mapelli F, Chernikova TN, Golyshin PN, Ferrer M, Daffonchio D. Enzyme adaptation to habitat thermal legacy shapes the thermal plasticity of marine microbiomes. Nat Commun 2023; 14:1045. [PMID: 36828822 PMCID: PMC9958047 DOI: 10.1038/s41467-023-36610-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Accepted: 02/08/2023] [Indexed: 02/26/2023] Open
Abstract
Microbial communities respond to temperature with physiological adaptation and compositional turnover. Whether thermal selection of enzymes explains marine microbiome plasticity in response to temperature remains unresolved. By quantifying the thermal behaviour of seven functionally-independent enzyme classes (esterase, extradiol dioxygenase, phosphatase, beta-galactosidase, nuclease, transaminase, and aldo-keto reductase) in native proteomes of marine sediment microbiomes from the Irish Sea to the southern Red Sea, we record a significant effect of the mean annual temperature (MAT) on enzyme response in all cases. Activity and stability profiles of 228 esterases and 5 extradiol dioxygenases from sediment and seawater across 70 locations worldwide validate this thermal pattern. Modelling the esterase phase transition temperature as a measure of structural flexibility confirms the observed relationship with MAT. Furthermore, when considering temperature variability in sites with non-significantly different MATs, the broadest range of enzyme thermal behaviour and the highest growth plasticity of the enriched heterotrophic bacteria occur in samples with the widest annual thermal variability. These results indicate that temperature-driven enzyme selection shapes microbiome thermal plasticity and that thermal variability finely tunes such processes and should be considered alongside MAT in forecasting microbial community thermal response.
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Affiliation(s)
- Ramona Marasco
- Biological and Environmental Sciences and Engineering Division (BESE), Red Sea Research Centre (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Marco Fusi
- Biological and Environmental Sciences and Engineering Division (BESE), Red Sea Research Centre (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Centre for Conservation and Restoration Science, Edinburgh Napier University Sighthill Campus, Edinburgh, UK
| | | | - Alan Barozzi
- Biological and Environmental Sciences and Engineering Division (BESE), Red Sea Research Centre (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - David Almendral
- Instituto de Catalisis y Petroleoquimica (ICP), CSIC, Madrid, Spain
| | - Rafael Bargiela
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Rd, Bangor, UK
| | | | - Christopher Pfleger
- Mathematisch-Naturwissenschaftliche Fakultät, Institut für Pharmazeutische und Medizinische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Jonas Dittrich
- Mathematisch-Naturwissenschaftliche Fakultät, Institut für Pharmazeutische und Medizinische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Holger Gohlke
- Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, Jülich, Germany
- Mathematisch-Naturwissenschaftliche Fakultät, Institut für Pharmazeutische und Medizinische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
- John von Neumann Institute for Computing (NIC) and Jülich Supercomputing Centre (JSC), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Ruth Matesanz
- Spectroscopy Laboratory, Centro de Investigaciones Biologicas Margarita Salas (CIB), CSIC, Madrid, Spain
| | - Sergio Sanchez-Carrillo
- Instituto de Catalisis y Petroleoquimica (ICP), CSIC, Madrid, Spain
- Centro de Biologia Molecular Severo Ochoa (CBM), CSIC-UAM, Madrid, Spain
| | - Francesca Mapelli
- Department of Food Environmental and Nutritional Sciences, University of Milan, Milan, Italy
| | - Tatyana N Chernikova
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Rd, Bangor, UK
| | - Peter N Golyshin
- Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Deiniol Rd, Bangor, UK
| | - Manuel Ferrer
- Instituto de Catalisis y Petroleoquimica (ICP), CSIC, Madrid, Spain.
| | - Daniele Daffonchio
- Biological and Environmental Sciences and Engineering Division (BESE), Red Sea Research Centre (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
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16
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Rivera M, Mjaavatten A, Smith SB, Baez M, Wilson CAM. Temperature dependent mechanical unfolding and refolding of a protein studied by thermo-regulated optical tweezers. Biophys J 2023; 122:513-521. [PMID: 36587240 PMCID: PMC9941719 DOI: 10.1016/j.bpj.2022.12.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 06/15/2022] [Accepted: 12/23/2022] [Indexed: 01/01/2023] Open
Abstract
Temperature is a useful system variable to gather kinetic and thermodynamic information from proteins. Usually, free energy and the associated entropic and enthalpic contributions are obtained by quantifying the conformational equilibrium based on melting experiments performed in bulk conditions. Such experiments are suitable only for those small single-domain proteins whose side reactions of irreversible aggregation are unlikely to occur. Here, we avoid aggregation by pulling single-protein molecules in a thermo-regulated optical tweezers. Thus, we are able to explore the temperature dependence of the thermodynamic and kinetic parameters of MJ0366 from Methanocaldococcus jannaschii at the single-molecule level. By performing force-ramp experiments between 2°C and 40°C, we found that MJ0366 has a nonlinear dependence of free energy with temperature and a specific heat change of 2.3 ± 1.2 kcal/mol∗K. These thermodynamic parameters are compatible with a two-state unfolding/refolding mechanism for MJ0366. However, the kinetics measured as a function of the temperature show a complex behavior, suggesting a three-state folding mechanism comprising a high-energy intermediate state. The combination of two perturbations, temperature and force, reveals a high-energy species in the folding mechanism of MJ0366 not detected in force-ramp experiments at constant temperature.
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Affiliation(s)
- Maira Rivera
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile; ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Santiago, Chile; Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | | | | | - Mauricio Baez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
| | - Christian A M Wilson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
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17
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Activation of L-lactate oxidase by the formation of enzyme assemblies through liquid-liquid phase separation. Sci Rep 2023; 13:1435. [PMID: 36697449 PMCID: PMC9877012 DOI: 10.1038/s41598-023-28040-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 01/11/2023] [Indexed: 01/26/2023] Open
Abstract
The assembly state of enzymes is gaining interest as a mechanism for regulating the function of enzymes in living cells. One of the current topics in enzymology is the relationship between enzyme activity and the assembly state due to liquid-liquid phase separation. In this study, we demonstrated enzyme activation via the formation of enzyme assemblies using L-lactate oxidase (LOX). LOX formed hundreds of nanometer-scale assemblies with poly-L-lysine (PLL). In the presence of ammonium sulfate, the LOX-PLL clusters formed micrometer-scale liquid droplets. The enzyme activities of LOX in clusters and droplets were one order of magnitude higher than those in the dispersed state, owing to a decrease in KM and an increase in kcat. Moreover, the clusters exhibited a higher activation effect than the droplets. In addition, the conformation of LOX changed in the clusters, resulting in increased enzyme activation. Understanding enzyme activation and assembly states provides important information regarding enzyme function in living cells, in addition to biotechnology applications.
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18
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Ma Y, Qing M, Zang J, Shan A, Zhang H, Chi Y, Chi Y, Gao X. Molecular interactions in the dry heat-facilitated hydrothermal gel formation of egg white protein. Food Res Int 2022; 162:112058. [DOI: 10.1016/j.foodres.2022.112058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 09/19/2022] [Accepted: 10/14/2022] [Indexed: 11/26/2022]
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19
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Conformational Stability and Denaturation Processes of Proteins Investigated by Electrophoresis under Extreme Conditions. Molecules 2022; 27:molecules27206861. [PMID: 36296453 PMCID: PMC9610776 DOI: 10.3390/molecules27206861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/10/2022] [Accepted: 10/10/2022] [Indexed: 11/17/2022] Open
Abstract
The functional structure of proteins results from marginally stable folded conformations. Reversible unfolding, irreversible denaturation, and deterioration can be caused by chemical and physical agents due to changes in the physicochemical conditions of pH, ionic strength, temperature, pressure, and electric field or due to the presence of a cosolvent that perturbs the delicate balance between stabilizing and destabilizing interactions and eventually induces chemical modifications. For most proteins, denaturation is a complex process involving transient intermediates in several reversible and eventually irreversible steps. Knowledge of protein stability and denaturation processes is mandatory for the development of enzymes as industrial catalysts, biopharmaceuticals, analytical and medical bioreagents, and safe industrial food. Electrophoresis techniques operating under extreme conditions are convenient tools for analyzing unfolding transitions, trapping transient intermediates, and gaining insight into the mechanisms of denaturation processes. Moreover, quantitative analysis of electrophoretic mobility transition curves allows the estimation of the conformational stability of proteins. These approaches include polyacrylamide gel electrophoresis and capillary zone electrophoresis under cold, heat, and hydrostatic pressure and in the presence of non-ionic denaturing agents or stabilizers such as polyols and heavy water. Lastly, after exposure to extremes of physical conditions, electrophoresis under standard conditions provides information on irreversible processes, slow conformational drifts, and slow renaturation processes. The impressive developments of enzyme technology with multiple applications in fine chemistry, biopharmaceutics, and nanomedicine prompted us to revisit the potentialities of these electrophoretic approaches. This feature review is illustrated with published and unpublished results obtained by the authors on cholinesterases and paraoxonase, two physiologically and toxicologically important enzymes.
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20
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Sinha I, Cramer SM, Ashbaugh HS, Garde S. Connecting Non-Gaussian Water Density Fluctuations to the Lengthscale Dependent Crossover in Hydrophobic Hydration. J Phys Chem B 2022; 126:7604-7614. [PMID: 36154059 DOI: 10.1021/acs.jpcb.2c04990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We connect density fluctuations in liquid water to lengthscale dependent crossover in hydrophobic hydration. Specifically, we employ indirect umbrella sampling (INDUS) simulations to characterize density fluctuations in observation volumes of various sizes and shapes in water and as a function of temperature and salt concentration. Consistent with previous observations, density fluctuations are Gaussian in small molecular scale volumes, but they display non-Gaussian "low-density fat tails" in larger volumes. These non-Gaussian tails are indicative of the proximity of water to its liquid to vapor phase transition and have implications on biomolecular interactions and function. We show that the onset of non-Gaussian fluctuations in large volumes is accompanied by the formation of a cavity in the observation volume. We develop a model that uses the physics of cavity-water interface formation as a key ingredient and show that it captures the nature of non-Gaussian density fluctuations over a broad region in water and in salt solutions. We discuss the limitations of this model in the very low density region of the distribution. Our calculations provide new insights into the origins of non-Gaussian density fluctuations in water and their connections to lengthscale dependent crossover in hydrophobic hydration.
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Affiliation(s)
- Imee Sinha
- Howard P. Isermann Department of Chemical and Biological Engineering and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, New York 12180, United States
| | - Steven M Cramer
- Howard P. Isermann Department of Chemical and Biological Engineering and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, New York 12180, United States
| | - Henry S Ashbaugh
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70123, United States
| | - Shekhar Garde
- Howard P. Isermann Department of Chemical and Biological Engineering and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, New York 12180, United States
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21
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Charles T, Moss DL, Bhat P, Moore PW, Kummer NA, Bhattacharya A, Landry SJ, Mettu RR. CD4+ T-Cell Epitope Prediction by Combined Analysis of Antigen Conformational Flexibility and Peptide-MHCII Binding Affinity. Biochemistry 2022; 61:1585-1599. [PMID: 35834502 PMCID: PMC9352311 DOI: 10.1021/acs.biochem.2c00237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Antigen processing in the class II MHC pathway depends
on conventional
proteolytic enzymes, potentially acting on antigens in native-like
conformational states. CD4+ epitope dominance arises from a competition
among antigen folding, proteolysis, and MHCII binding. Protease-sensitive
sites, linear antibody epitopes, and CD4+ T-cell epitopes were mapped
in plague vaccine candidate F1-V to evaluate the various contributions
to CD4+ epitope dominance. Using X-ray crystal structures, antigen
processing likelihood (APL) predicts CD4+ epitopes with significant
accuracy for F1-V without considering peptide-MHCII binding affinity.
We also show that APL achieves excellent performance over two benchmark
antigen sets. The profiles of conformational flexibility derived from
the X-ray crystal structures of the F1-V proteins, Caf1 and LcrV,
were similar to the biochemical profiles of linear antibody epitope
reactivity and protease sensitivity, suggesting that the role of structure
in proteolysis was captured by the analysis of the crystal structures.
The patterns of CD4+ T-cell epitope dominance in C57BL/6, CBA, and
BALB/c mice were compared to epitope predictions based on APL, MHCII
binding, or both. For a sample of 13 diverse antigens, the accuracy
of epitope prediction by the combination of APL and I-Ab-MHCII-peptide affinity reached 36%. When MHCII allele specificity
was also diverse, such as in human immunity, prediction of dominant
epitopes by APL alone reached 42% when using a stringent scoring threshold.
Because dominant CD4+ epitopes tend to occur in conformationally stable
antigen domains, crystal structures typically are available for analysis
by APL, and thus, the requirement for a crystal structure is not a
severe limitation.
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Affiliation(s)
- Tysheena Charles
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Daniel L Moss
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Pawan Bhat
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Peyton W Moore
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Nicholas A Kummer
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Avik Bhattacharya
- Department of Computer Science, Tulane University, New Orleans, Louisiana 70118, United States
| | - Samuel J Landry
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Ramgopal R Mettu
- Department of Computer Science, Tulane University, New Orleans, Louisiana 70118, United States
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22
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Heimsch KC, Gertzen CGW, Schuh AK, Nietzel T, Rahlfs S, Przyborski JM, Gohlke H, Schwarzländer M, Becker K, Fritz-Wolf K. Structure and Function of Redox-Sensitive Superfolder Green Fluorescent Protein Variant. Antioxid Redox Signal 2022; 37:1-18. [PMID: 35072524 PMCID: PMC9293687 DOI: 10.1089/ars.2021.0234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Aims: Genetically encoded green fluorescent protein (GFP)-based redox biosensors are widely used to monitor specific and dynamic redox processes in living cells. Over the last few years, various biosensors for a variety of applications were engineered and enhanced to match the organism and cellular environments, which should be investigated. In this context, the unicellular intraerythrocytic parasite Plasmodium, the causative agent of malaria, represents a challenge, as the small size of the organism results in weak fluorescence signals that complicate precise measurements, especially for cell compartment-specific observations. To address this, we have functionally and structurally characterized an enhanced redox biosensor superfolder roGFP2 (sfroGFP2). Results: SfroGFP2 retains roGFP2-like behavior, yet with improved fluorescence intensity (FI) in cellulo. SfroGFP2-based redox biosensors are pH insensitive in a physiological pH range and show midpoint potentials comparable with roGFP2-based redox biosensors. Using crystallography and rigidity theory, we identified the superfolding mutations as being responsible for improved structural stability of the biosensor in a redox-sensitive environment, thus explaining the improved FI in cellulo. Innovation: This work provides insight into the structure and function of GFP-based redox biosensors. It describes an improved redox biosensor (sfroGFP2) suitable for measuring oxidizing effects within small cells where applicability of other redox sensor variants is limited. Conclusion: Improved structural stability of sfroGFP2 gives rise to increased FI in cellulo. Fusion to hGrx1 (human glutaredoxin-1) provides the hitherto most suitable biosensor for measuring oxidizing effects in Plasmodium. This sensor is of major interest for studying glutathione redox changes in small cells, as well as subcellular compartments in general. Antioxid. Redox Signal. 37, 1-18.
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Affiliation(s)
- Kim C Heimsch
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Christoph G W Gertzen
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.,Center for Structural Studies (CSS), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Anna Katharina Schuh
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Thomas Nietzel
- Institute of Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Stefan Rahlfs
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Jude M Przyborski
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.,John von Neumann Institute of Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Markus Schwarzländer
- Institute of Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Karin Fritz-Wolf
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany.,Max-Planck Institute of Medical Research, Heidelberg, Germany
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23
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The Thermodynamic Stability of Membrane Proteins in Micelles and Lipid Bilayers Investigated with the Ferrichrom Receptor FhuA. J Membr Biol 2022; 255:485-502. [PMID: 35552784 PMCID: PMC9581862 DOI: 10.1007/s00232-022-00238-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/05/2022] [Indexed: 12/03/2022]
Abstract
Extraction of integral membrane proteins into detergents for structural and functional studies often leads to a strong loss in protein stability. The impact of the lipid bilayer on the thermodynamic stability of an integral membrane protein in comparison to its solubilized form in detergent was examined and compared for FhuA from Escherichia coli and for a mutant, FhuAΔ5-160, lacking the N-terminal cork domain. Urea-induced unfolding was monitored by fluorescence spectroscopy to determine the effective free energies \documentclass[12pt]{minimal}
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\begin{document}$$ \Delta G{^\text{o}_{\rm u}} $$\end{document}ΔGuo of unfolding. To obtain enthalpic and entropic contributions of unfolding of FhuA, \documentclass[12pt]{minimal}
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\begin{document}$$ \Delta G{^\text{o}_{\rm u}} $$\end{document}ΔGuo were determined at various temperatures. When solubilized in LDAO detergent, wt-FhuA and FhuAΔ5-160 unfolded in a single step. The 155-residue cork domain stabilized wt-FhuA by \documentclass[12pt]{minimal}
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\begin{document}$$ \Delta\Delta G{^\text{o}_{\rm u}} $$\end{document}ΔΔGuo~ 40 kJ/mol. Reconstituted into lipid bilayers, wt-FhuA unfolded in two steps, while FhuAΔ5-160 unfolded in a single step, indicating an uncoupled unfolding of the cork domain. For FhuAΔ5-160 at 35 °C, \documentclass[12pt]{minimal}
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\begin{document}$$ \Delta G{^\text{o}_{\rm u}} $$\end{document}ΔGuo increased from ~ 5 kJ/mol in LDAO micelles to about ~ 20 kJ/mol in lipid bilayers, while the temperature of unfolding increased from TM ~ 49 °C in LDAO micelles to TM ~ 75 °C in lipid bilayers. Enthalpies \documentclass[12pt]{minimal}
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\begin{document}$$\Delta H{_{\rm M}^\text{o}}$$\end{document}ΔHMowere much larger than free energies \documentclass[12pt]{minimal}
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\begin{document}$$ \Delta G{^\text{o}_{\rm u}} $$\end{document}ΔGuo, for FhuAΔ5-160 and for wt-FhuA, and compensated by a large gain of entropy upon unfolding. The gain in conformational entropy is expected to be similar for unfolding of FhuA from micelles or bilayers. The strongly increased TM and \documentclass[12pt]{minimal}
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\begin{document}$$\Delta H{_{\rm M}^\text{o}}$$\end{document}ΔHMo observed for the lipid bilayer-reconstituted FhuA in comparison to the LDAO-solubilized forms, therefore, very likely arise from a much-increased solvation entropy of FhuA in bilayers.
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Lubin JH, Zardecki C, Dolan EM, Lu C, Shen Z, Dutta S, Westbrook JD, Hudson BP, Goodsell DS, Williams JK, Voigt M, Sarma V, Xie L, Venkatachalam T, Arnold S, Alfaro Alvarado LH, Catalfano K, Khan A, McCarthy E, Staggers S, Tinsley B, Trudeau A, Singh J, Whitmore L, Zheng H, Benedek M, Currier J, Dresel M, Duvvuru A, Dyszel B, Fingar E, Hennen EM, Kirsch M, Khan AA, Labrie‐Cleary C, Laporte S, Lenkeit E, Martin K, Orellana M, Ortiz‐Alvarez de la Campa M, Paredes I, Wheeler B, Rupert A, Sam A, See K, Soto Zapata S, Craig PA, Hall BL, Jiang J, Koeppe JR, Mills SA, Pikaart MJ, Roberts R, Bromberg Y, Hoyer JS, Duffy S, Tischfield J, Ruiz FX, Arnold E, Baum J, Sandberg J, Brannigan G, Khare SD, Burley SK. Evolution of the SARS-CoV-2 proteome in three dimensions (3D) during the first 6 months of the COVID-19 pandemic. Proteins 2022; 90:1054-1080. [PMID: 34580920 PMCID: PMC8661935 DOI: 10.1002/prot.26250] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 08/26/2021] [Accepted: 09/16/2021] [Indexed: 01/18/2023]
Abstract
Understanding the molecular evolution of the SARS-CoV-2 virus as it continues to spread in communities around the globe is important for mitigation and future pandemic preparedness. Three-dimensional structures of SARS-CoV-2 proteins and those of other coronavirusess archived in the Protein Data Bank were used to analyze viral proteome evolution during the first 6 months of the COVID-19 pandemic. Analyses of spatial locations, chemical properties, and structural and energetic impacts of the observed amino acid changes in >48 000 viral isolates revealed how each one of 29 viral proteins have undergone amino acid changes. Catalytic residues in active sites and binding residues in protein-protein interfaces showed modest, but significant, numbers of substitutions, highlighting the mutational robustness of the viral proteome. Energetics calculations showed that the impact of substitutions on the thermodynamic stability of the proteome follows a universal bi-Gaussian distribution. Detailed results are presented for potential drug discovery targets and the four structural proteins that comprise the virion, highlighting substitutions with the potential to impact protein structure, enzyme activity, and protein-protein and protein-nucleic acid interfaces. Characterizing the evolution of the virus in three dimensions provides testable insights into viral protein function and should aid in structure-based drug discovery efforts as well as the prospective identification of amino acid substitutions with potential for drug resistance.
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Affiliation(s)
- Joseph H. Lubin
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Christine Zardecki
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data BankRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Elliott M. Dolan
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Changpeng Lu
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Zhuofan Shen
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Shuchismita Dutta
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data BankRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
| | - John D. Westbrook
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data BankRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
| | - Brian P. Hudson
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data BankRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - David S. Goodsell
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data BankRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
- The Scripps Research InstituteLa JollaCaliforniaUSA
| | - Jonathan K. Williams
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Maria Voigt
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data BankRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Vidur Sarma
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Lingjun Xie
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Thejasvi Venkatachalam
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Steven Arnold
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | | | | | - Aaliyah Khan
- University of Maryland Baltimore CountyBaltimoreMarylandUSA
| | | | | | | | | | | | | | - Helen Zheng
- Watchung Hills Regional High SchoolWarrenNew JerseyUSA
| | | | | | - Mark Dresel
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | | | | | | | | | | | | | | | | | - Evan Lenkeit
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | | | | | | | | | | | | | - Andrew Sam
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Katherine See
- Rochester Institute of TechnologyRochesterNew YorkUSA
| | | | - Paul A. Craig
- Rochester Institute of TechnologyRochesterNew YorkUSA
| | | | - Jennifer Jiang
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | | | | | | | | | - Yana Bromberg
- Department of Biochemistry and MicrobiologyRutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
| | - J. Steen Hoyer
- Department of Ecology, Evolution and Natural Resources, School of Environmental and Biological SciencesRutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
| | - Siobain Duffy
- Department of Ecology, Evolution and Natural Resources, School of Environmental and Biological SciencesRutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
| | - Jay Tischfield
- Department of GeneticsRutgers, The State University of New Jersey, and Human Genetics Institute of New JerseyPiscatawayNew JerseyUSA
| | - Francesc X. Ruiz
- Center for Advanced Biotechnology and MedicineRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Eddy Arnold
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Center for Advanced Biotechnology and MedicineRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Jean Baum
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Jesse Sandberg
- Center for Computational and Integrative BiologyRutgers, The State University of New JerseyCamdenNew JerseyUSA
| | - Grace Brannigan
- Center for Computational and Integrative BiologyRutgers, The State University of New JerseyCamdenNew JerseyUSA
- Department of PhysicsRutgers, The State University of New JerseyCamdenNew JerseyUSA
| | - Sagar D. Khare
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
| | - Stephen K. Burley
- Institute for Quantitative Biomedicine, Rutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data BankRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
- Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, Rutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
- Research Collaboratory for Structural Bioinformatics Protein Data Bank, San Diego Supercomputer CenterUniversity of CaliforniaSan Diego, La JollaCaliforniaUSA
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25
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Reverse Engineering Analysis of the High-Temperature Reversible Oligomerization and Amyloidogenicity of PSD95-PDZ3. Molecules 2022; 27:molecules27092813. [PMID: 35566161 PMCID: PMC9103278 DOI: 10.3390/molecules27092813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/09/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023] Open
Abstract
PSD95-PDZ3, the third PDZ domain of the post-synaptic density-95 protein (MW 11 kDa), undergoes a peculiar three-state thermal denaturation (N ↔ In ↔ D) and is amyloidogenic. PSD95-PDZ3 in the intermediate state (I) is reversibly oligomerized (RO: Reversible oligomerization). We previously reported a point mutation (F340A) that inhibits both ROs and amyloidogenesis and constructed the PDZ3-F340A variant. Here, we “reverse engineered” PDZ3-F340A for inducing high-temperature RO and amyloidogenesis. We produced three variants (R309L, E310L, and N326L), where we individually mutated hydrophilic residues exposed at the surface of the monomeric PDZ3-F340A but buried in the tetrameric crystal structure to a hydrophobic leucine. Differential scanning calorimetry indicated that two of the designed variants (PDZ3-F340A/R309L and E310L) denatured according to the two-state model. On the other hand, PDZ3-F340A/N326L denatured according to a three-state model and produced high-temperature ROs. The secondary structures of PDZ3-F340A/N326L and PDZ3-wt in the RO state were unfolded according to circular dichroism and differential scanning calorimetry. Furthermore, PDZ3-F340A/N326L was amyloidogenic as assessed by Thioflavin T fluorescence. Altogether, these results demonstrate that a single amino acid mutation can trigger the formation of high-temperature RO and concurrent amyloidogenesis.
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Seelig J, Seelig A. Molecular understanding of calorimetric protein unfolding experiments. BIOPHYSICAL REPORTS 2022; 2:100037. [PMID: 36425081 PMCID: PMC9680786 DOI: 10.1016/j.bpr.2021.100037] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/02/2021] [Indexed: 06/16/2023]
Abstract
Testing and predicting protein stability gained importance because proteins, including antibodies, became pharmacologically relevant in viral and cancer therapies. Isothermal scanning calorimetry is the principle method to study protein stability. Here, we use the excellent experimental heat capacity Cp(T) data from the literature for a critical inspection of protein unfolding as well as for the test of a new cooperative model. In the relevant literature, experimental temperature profiles of enthalpy, Hcal(T), entropy, Scal(T), and free energy, Gcal(T) are missing. First, we therefore calculate the experimental Hcal(T), Scal(T), and Gcal(T) from published Cp(T) thermograms. Considering only the unfolding transition proper, the heat capacity and all thermodynamic functions are zero in the region of the native protein. In particular, the free energy of the folded proteins is also zero and Gcal(T) displays a trapezoidal temperature profile when cold denaturation is included. Second, we simulate the DSC-measured thermodynamic properties with a new molecular model based on statistical-mechanical thermodynamics. The model quantifies the protein cooperativity and predicts the aggregate thermodynamic variables of the system with molecular parameters only. The new model provides a perfect simulation of all thermodynamic properties, including the observed trapezoidal Gcal(T) temperature profile. Importantly, the new cooperative model can be applied to a broad range of protein sizes, including antibodies. It predicts not only heat and cold denaturation but also provides estimates of the unfolding kinetics and allows a comparison with molecular dynamics calculations and quasielastic neutron scattering experiments.
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Affiliation(s)
| | - Anna Seelig
- Biozentrum, University of Basel, Basel, Switzerland
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27
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Non-covalent interaction of soy protein isolate and catechin: Mechanism and effects on protein conformation. Food Chem 2022; 384:132507. [PMID: 35217462 DOI: 10.1016/j.foodchem.2022.132507] [Citation(s) in RCA: 75] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 12/23/2021] [Accepted: 02/16/2022] [Indexed: 01/27/2023]
Abstract
Understanding the molecular mechanism behind protein-polyphenol interactions is critical for the application of protein-polyphenol compounds in foods. The purpose of this research was to investigate the non-covalent interaction mechanism between soy protein isolate (SPI) and catechin and its effect on protein conformation. We observed that particle size, ζ-potential, and polyphenol bound equivalents of SPI increased significantly after non-covalent modification with catechin. These changes caused SPI to aggregate and form a network-like structure. Fourier transform infrared spectroscopy (FTIR) indicated that increased catechin concentrations caused SPI to become looser and more disordered as its α-helix and β-sheet transformed into β-turn and random coil. Furthermore, internal structure of SPI was opened and its hydrophobic groups were exposed to a polar environment, which was demonstrated by decreased surface hydrophobicity. Thermodynamic analysis and molecular docking results showed that the main forces present between SPI and catechin were hydrophobic interactions and hydrogen bonds.
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28
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Impact of Single Amino Acid Substitutions in Parkinsonism-Associated Deglycase-PARK7 and Their Association with Parkinson’s Disease. J Pers Med 2022; 12:jpm12020220. [PMID: 35207708 PMCID: PMC8878504 DOI: 10.3390/jpm12020220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 12/25/2021] [Accepted: 12/30/2021] [Indexed: 01/09/2023] Open
Abstract
Parkinsonism-associated deglycase-PARK7/DJ-1 (PARK7) is a multifunctional protein having significant roles in inflammatory and immune disorders and cell protection against oxidative stress. Mutations in PARK7 may result in the onset and progression of a few neurodegenerative disorders such as Parkinson’s disease. This study has analyzed the non-synonymous single nucleotide polymorphisms (nsSNPs) resulting in single amino acid substitutions in PARK7 to explore its disease-causing variants and their structural dysfunctions. Initially, we retrieved the mutational dataset of PARK7 from the Ensembl database and performed detailed analyses using sequence-based and structure-based approaches. The pathogenicity of the PARK7 was then performed to distinguish the destabilizing/deleterious variants. Aggregation propensity, noncovalent interactions, packing density, and solvent accessible surface area analyses were carried out on the selected pathogenic mutations. The SODA study suggested that mutations in PARK7 result in aggregation, inducing disordered helix and altering the strand propensity. The effect of mutations alters the number of hydrogen bonds and hydrophobic interactions in PARK7, as calculated from the Arpeggio server. The study indicated that the alteration in the hydrophobic contacts and frustration of the protein could alter the stability of the missense variants of the PARK7, which might result in disease progression. This study provides a detailed understanding of the destabilizing effects of single amino acid substitutions in PARK7.
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29
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The native state conformational heterogeneity in the energy landscape of protein folding. Biophys Chem 2022; 283:106761. [DOI: 10.1016/j.bpc.2022.106761] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 01/10/2022] [Accepted: 01/14/2022] [Indexed: 11/18/2022]
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30
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Saotome T, Onchaiya S, Subbaian B, Mezaki T, Unzai S, Noguchi K, Martinez JC, Kidokoro SI, Kuroda Y. Blocking PSD95-PDZ3's amyloidogenesis through point mutations that inhibit high-temperature reversible oligomerization (RO). FEBS J 2021; 289:3205-3216. [PMID: 34967499 DOI: 10.1111/febs.16339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 11/05/2021] [Accepted: 12/29/2021] [Indexed: 11/30/2022]
Abstract
The third PDZ domain of postsynaptic density protein 95 (PSD95-PDZ3; 11 kDa, 103 residues) has a propensity to form amyloid fibrils at high temperatures. At neutral pH, wild type PDZ3 is natively folded, but it exhibits a peculiar three-state thermal unfolding with a reversible oligomerization (RO) equilibrium at high temperatures, which is uncharacteristic in the unfolding of small globular protein as PDZ3 is. Here, we examined RO's role in PDZ3's amyloidogenesis at high-temperature using two variants (F340A and L342A) that suppress the high-temperature RO and five single-alanine-mutated variants, where we mutated surface-exposed hydrophobic residues to alanine. Circular Dichroism (CD), Analytical Ultracentrifuge (AUC), and other spectroscopic measurements confirmed the retention of the native structure at ambient temperature. Differential Scanning Calorimetry (DSC) was used to assess the presence or absence of the high-temperature RO, and the amyloidogenicity of the variants was measured by Thioflavin T (ThT) fluorescence and Transmission Electron Microscopy (TEM). By comparing the fraction of RO and the ThT signal, we found that mutations that suppressed the high-temperature RO strongly inhibited amyloidogenesis. On the other hand, all variants forming RO also formed amyloids under the same conditions as the wild type PDZ3.
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Affiliation(s)
- Tomonori Saotome
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16, Nakamachi, Koganei, Tokyo, 184-8588, Japan.,Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, 3-8-1, Harumi-cho, Fuchu, Tokyo, 183-8538, Japan.,Department of Bioengineering, Nagaoka University of Technology, Kamitomioka-cho, Nagaoka, Niigata, 940-2188, Japan
| | - Sawaros Onchaiya
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16, Nakamachi, Koganei, Tokyo, 184-8588, Japan
| | - Brindha Subbaian
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16, Nakamachi, Koganei, Tokyo, 184-8588, Japan
| | - Taichi Mezaki
- Department of Bioengineering, Nagaoka University of Technology, Kamitomioka-cho, Nagaoka, Niigata, 940-2188, Japan
| | - Satoru Unzai
- Department of Frontier Bioscience, Faculty of Bioscience and Applied Chemistry, Hosei University, Kajino-cho, Koganei, Tokyo, 185-8584, Japan.,Research Center for Micro-Nano Technology, Hosei University, Midori-cho, Koganei, Tokyo, 184-0003, Japan
| | - Keiichi Noguchi
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16, Nakamachi, Koganei, Tokyo, 184-8588, Japan
| | - Jose C Martinez
- Department of Physical Chemistry and Institute of Biotechnology, Faculty of Sciences, University of Granada, 18071, Granada, Spain
| | - Shun-Ichi Kidokoro
- Department of Bioengineering, Nagaoka University of Technology, Kamitomioka-cho, Nagaoka, Niigata, 940-2188, Japan
| | - Yutaka Kuroda
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16, Nakamachi, Koganei, Tokyo, 184-8588, Japan.,Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, 3-8-1, Harumi-cho, Fuchu, Tokyo, 183-8538, Japan
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31
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Xia W, Bai Y, Shi P. Improving the Substrate Affinity and Catalytic Efficiency of β-Glucosidase Bgl3A from Talaromyces leycettanus JCM12802 by Rational Design. Biomolecules 2021; 11:biom11121882. [PMID: 34944526 PMCID: PMC8699594 DOI: 10.3390/biom11121882] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 12/31/2022] Open
Abstract
Improving the substrate affinity and catalytic efficiency of β-glucosidase is necessary for better performance in the enzymatic saccharification of cellulosic biomass because of its ability to prevent cellobiose inhibition on cellulases. Bgl3A from Talaromyces leycettanus JCM12802, identified in our previous work, was considered a suitable candidate enzyme for efficient cellulose saccharification with higher catalytic efficiency on the natural substrate cellobiose compared with other β-glucosidase but showed insufficient substrate affinity. In this work, hydrophobic stacking interaction and hydrogen-bonding networks in the active center of Bgl3A were analyzed and rationally designed to strengthen substrate binding. Three vital residues, Met36, Phe66, and Glu168, which were supposed to influence substrate binding by stabilizing adjacent binding site, were chosen for mutagenesis. The results indicated that strengthening the hydrophobic interaction between stacking aromatic residue and the substrate, and stabilizing the hydrogen-bonding networks in the binding pocket could contribute to the stabilized substrate combination. Four dominant mutants, M36E, M36N, F66Y, and E168Q with significantly lower Km values and 1.4–2.3-fold catalytic efficiencies, were obtained. These findings may provide a valuable reference for the design of other β-glucosidases and even glycoside hydrolases.
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Affiliation(s)
- Wei Xia
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100081, China;
| | - Yingguo Bai
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Correspondence: (Y.B.); (P.S.)
| | - Pengjun Shi
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100081, China;
- Correspondence: (Y.B.); (P.S.)
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32
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Durell SR, Ben-Naim A. Temperature Dependence of Hydrophobic and Hydrophilic Forces and Interactions. J Phys Chem B 2021; 125:13137-13146. [PMID: 34850632 DOI: 10.1021/acs.jpcb.1c07802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular dynamics simulations are used to compare the forces and Gibbs free energies associated with bringing small hydrophobic and hydrophilic solutes together in an aqueous solution at different temperatures between 280 and 360 °K. For the hydrophilic solutes, different relative orientations are used to distinguish between direct, intersolute hydrogen bonds (Hbond) and solutes simultaneously hydrogen bonding to a solvent water bridge. Interestingly, the temperature dependence of the hydrophobic and directly hydrogen bonding solutes turns out to be opposite to that of the bridged hydrophilic solutes, with the ΔG becoming more negative for the former and less negative for the latter with increasing temperature. Dissection of the free energy curves into enthalpy and entropy contributions, and further separation of the enthalpy term into solute-solute, solute-solvent, and solvent-solvent components provides insight into the physical molecular causes for the distinctive thermodynamic results. Finally, it is reasoned how the opposite temperature dependencies of the two types of hydrophilic interactions provide a rationale for the cold denaturation of proteins.
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Affiliation(s)
- Stewart R Durell
- Laboratory of Cell Biology, National Cancer Institute; National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Arieh Ben-Naim
- Department of Physical Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus Givat Ram, Jerusalem 91904, Israel
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33
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Lanza G, Chiacchio MA. On the size, shape and energetics of the hydration shell around alkanes. Phys Chem Chem Phys 2021; 23:24852-24865. [PMID: 34723301 DOI: 10.1039/d1cp02888j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A large number of clathrate-like cages have been proposed as the very first hydration shell of alkanes. The cages include canonical structures commonly found in clathrate hydrates and many others, not previously reported, derived from the carbon fullerene cavities. These structures have a rich and variegated form, which can adapt to the shape and conformation of the solute. They avoid "wasting" hydrogen bonds, while minimizing the volume cage and maximizing the solute-solvent van der Waals interactions. DFT/M06-2X and MP2 ab initio calculations give comparable structural and energetic results although the latter predicts slightly larger cages for a given solute. It is shown that the van der Waals interactions are substantial and the large exoenergetic values found for isobutane and cyclopentane provide an explanation for the surprising high melting points of related hydrates at room pressure. The encaging enthalpy for various hydrocarbons is similar to the enthalpy of solution measured at a temperature just above the melting point of aqueous hydrocarbon solutions, thus indicating that water molecules should not deviate too much from the configuration with O-H bonds tangentially oriented with respect to the solute surface. The computed trend differs from the enthalpy of solution measured at room temperature, thus the very first hydration shell departs, up to a certain degree, from the clathrate-like structures.
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Affiliation(s)
- Giuseppe Lanza
- A Dipartimento di Scienze del Farmaco e della Salute, Università di Catania, Viale A. Doria 6, Catania, Italy.
| | - Maria Assunta Chiacchio
- A Dipartimento di Scienze del Farmaco e della Salute, Università di Catania, Viale A. Doria 6, Catania, Italy.
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34
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Li Y, Liu L, Zhao H. Enzyme-catalyzed cascade reactions on multienzyme proteinosomes. J Colloid Interface Sci 2021; 608:2593-2601. [PMID: 34763887 DOI: 10.1016/j.jcis.2021.10.185] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/21/2021] [Accepted: 10/29/2021] [Indexed: 10/19/2022]
Abstract
In this research, to mimic the structures and the functionalities of the organelles in living cells multienzyme proteinosomes with β-galactosidase (β-gal), glucose oxidase (GOx) and horseradish peroxidase (HRP) on the surfaces are fabricated by hydrophobic-interaction induced self-assembly approach. To investigate the mechanism of the formation of proteinosomes, poly(di(ethylene glycol) methyl ether methacrylate) (PDEGMA) and bovine serum albumin are employed in a model system and the study demonstrates that the hydrophobic interaction between the dehydrated polymer chains and the hydrophobic patches on the proteins plays a key role in the fabrication of the proteinosomes. Based on the model system, multienzyme proteinosomes with β-gal, GOx and HRP on the surfaces are fabricated through hydrophobic interaction between PDEGMA and enzyme molecules. Enzyme-catalyzed cascade reactions are performed on the surfaces of the proteinosomes, and the immobilized enzymes show higher bioactivities than the "free" enzymes, due to the direct transfer of the product as a substrate from one enzyme molecule to another. This research provides a unique method for the synthesis of multienzyme proteinosomes with improved bioactivities, and the biofunctional structures will find promising applications in medical and biological science.
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Affiliation(s)
- Yuwei Li
- Key Laboratory of Functional Polymer Materials, Ministry of Education, College of Chemistry, Nankai University, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, China
| | - Li Liu
- Key Laboratory of Functional Polymer Materials, Ministry of Education, College of Chemistry, Nankai University, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, China.
| | - Hanying Zhao
- Key Laboratory of Functional Polymer Materials, Ministry of Education, College of Chemistry, Nankai University, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, China.
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Thermodynamic and structural basis of temperature-dependent gating in TRP channels. Biochem Soc Trans 2021; 49:2211-2219. [PMID: 34623379 DOI: 10.1042/bst20210301] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 09/16/2021] [Accepted: 09/21/2021] [Indexed: 11/17/2022]
Abstract
Living organisms require detecting the environmental thermal clues for survival, allowing them to avoid noxious stimuli or find prey moving in the dark. In mammals, the Transient Receptor Potential ion channels superfamily is constituted by 27 polymodal receptors whose activity is controlled by small ligands, peptide toxins, protons and voltage. The thermoTRP channels subgroup exhibits unparalleled temperature dependence -behaving as heat and cold sensors. Functional studies have dissected their biophysical features in detail, and the advances of single-particle Cryogenic Electron microscopy provided the structural framework required to propose detailed channel gating mechanisms. However, merging structural and functional evidence for temperature-driven gating of thermoTRP channels has been a hard nut to crack, remaining an open question nowadays. Here we revisit the highlights on the study of heat and cold sensing in thermoTRP channels in the light of the structural data that has emerged during recent years.
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Zainol MKM, Linforth RJC, Winzor DJ, Scott DJ. Thermodynamics of semi-specific ligand recognition: the binding of dipeptides to the E.coli dipeptide binding protein DppA. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2021; 50:1103-1110. [PMID: 34611772 PMCID: PMC8566422 DOI: 10.1007/s00249-021-01572-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/23/2021] [Accepted: 09/18/2021] [Indexed: 12/04/2022]
Abstract
This investigation of the temperature dependence of DppA interactions with a subset of three dipeptides (AA. AF and FA) by isothermal titration calorimetry has revealed the negative heat capacity (\documentclass[12pt]{minimal}
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\begin{document}$$\Delta {C}_{p}^{o}$$\end{document}ΔCpo) that is a characteristic of hydrophobic interactions. The observation of enthalpy–entropy compensation is interpreted in terms of the increased structuring of water molecules trapped in a hydrophobic environment, the enthalpic energy gain from which is automatically countered by the entropy decrease associated with consequent loss of water structure flexibility. Specificity for dipeptides stems from appropriate spacing of designated DppA aspartate and arginine residues for electrostatic interaction with the terminal amino and carboxyl groups of a dipeptide, after which the binding pocket closes to become completely isolated from the aqueous environment. Any differences in chemical reactivity of the dipeptide sidechains are thereby modulated by their occurrence in a hydrophobic environment where changes in the structural state of entrapped water molecules give rise to the phenomenon of enthalpy–entropy compensation. The consequent minimization of differences in the value of ΔG0 for all DppA–dipeptide interactions thus provides thermodynamic insight into the biological role of DppA as a transporter of all dipeptides across the periplasmic membrane.
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Affiliation(s)
- Mohamad K M Zainol
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, LE12 5RD, UK.,Faculty of Fisheries and Food Science, Universiti Malaysia Terengganu, Mengabang Telipot, 21030, Kuala Nerus, Terengganu, Malaysia
| | - Robert J C Linforth
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, LE12 5RD, UK
| | - Donald J Winzor
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD, 4072, Australia
| | - David J Scott
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, LE12 5RD, UK. .,Rutherford Appleton Laboratory, Research Complex at Harwell, Oxfordshire, OX11 0FA, UK.
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38
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Dung DN, Phan AD, Nguyen TT, Lam VD. Effects of surface charge and environmental factors on the electrostatic interaction of fiber with virus-like particle: A case of coronavirus. AIP ADVANCES 2021; 11:105008. [PMID: 34646585 PMCID: PMC8501974 DOI: 10.1063/5.0065147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/25/2021] [Indexed: 05/09/2023]
Abstract
We propose a theoretical model to elucidate intermolecular electrostatic interactions between a virus and a substrate. Our model treats the virus as a homogeneous particle having surface charge and the polymer fiber of the respirator as a charged plane. Electric potentials surrounding the virus and fiber are influenced by the surface charge distribution of the virus. We use Poisson-Boltzmann equations to calculate electric potentials. Then, Derjaguin's approximation and a linear superposition of the potential function are extended to determine the electrostatic force. In this work, we apply this model for coronavirus or SARS-CoV-2 case and numerical results quantitatively agree with prior simulation. We find that the influence of fiber's potential on the surface charge of the virus is important and is considered in interaction calculations to obtain better accuracy. The electrostatic interaction significantly decays with increasing separation distance, and this curve becomes steeper when adding more salt. Although the interaction force increases with heating, one can observe the repulsive-attractive transition when the environment is acidic.
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Affiliation(s)
- D. N. Dung
- Faculty of Materials Science and Engineering, Phenikaa University, Yen Nghia, Ha Dong, Ha Noi 12116, Vietnam
| | - Anh D. Phan
- Author to whom correspondence should be addressed:
| | - Toan T. Nguyen
- Key Laboratory for Multiscale Simulation of Complex Systems, and Department of Theoretical Physics, Faculty of Physics, VNU University of Science, Vietnam National University—Hanoi, 334 Nguyen Trai Street, Thanh Xuan District, Hanoi 10000, Vietnam
| | - Vu D. Lam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam
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39
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Ashbaugh HS. Reversal of the Temperature Dependence of Hydrophobic Hydration in Supercooled Water. J Phys Chem Lett 2021; 12:8370-8375. [PMID: 34435491 PMCID: PMC8419862 DOI: 10.1021/acs.jpclett.1c02399] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 08/23/2021] [Indexed: 06/13/2023]
Abstract
Using simulations and theory, we examine the enthalpy and entropy of hydrophobic hydration which exhibit minima in supercooled water, contrasting with the monotonically increasing temperature dependence traditionally ascribed to these properties. The enthalpy/entropy minima are marked by a negative to positive sign change in the heat capacity at a size-dependent reversal temperature. A Gaussian fluctuation theory accurately captures the reversal temperature, tracing it to water's distinct thermal expansivity and compressibility influenced by its metastable liquid-liquid critical point.
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40
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Ernst M, Robertson JL. The Role of the Membrane in Transporter Folding and Activity. J Mol Biol 2021; 433:167103. [PMID: 34139219 PMCID: PMC8756397 DOI: 10.1016/j.jmb.2021.167103] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 12/23/2022]
Abstract
The synthesis, folding, and function of membrane transport proteins are critical factors for defining cellular physiology. Since the stability of these proteins evolved amidst the lipid bilayer, it is no surprise that we are finding that many of these membrane proteins demonstrate coupling of their structure or activity in some way to the membrane. More and more transporter structures are being determined with some information about the surrounding membrane, and computational modeling is providing further molecular details about these solvation structures. Thus, the field is moving towards identifying which molecular mechanisms - lipid interactions, membrane perturbations, differential solvation, and bulk membrane effects - are involved in linking membrane energetics to transporter stability and function. In this review, we present an overview of these mechanisms and the growing evidence that the lipid bilayer is a major determinant of the fold, form, and function of membrane transport proteins in membranes.
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Affiliation(s)
- Melanie Ernst
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine in St. Louis, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - Janice L Robertson
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine in St. Louis, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
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Romero-Romero S, Costas M, Silva Manzano DA, Kordes S, Rojas-Ortega E, Tapia C, Guerra Y, Shanmugaratnam S, Rodríguez-Romero A, Baker D, Höcker B, Fernández-Velasco DA. The Stability Landscape of de novo TIM Barrels Explored by a Modular Design Approach. J Mol Biol 2021; 433:167153. [PMID: 34271011 PMCID: PMC8404036 DOI: 10.1016/j.jmb.2021.167153] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/18/2021] [Accepted: 07/06/2021] [Indexed: 11/25/2022]
Abstract
The TIM barrel is a versatile fold to understand structure-stability relationships. A collection of de novo TIM barrels with improved hydrophobic cores was designed. DeNovoTIMs are reversible in chemical and thermal unfolding, which is uncommon in TIM barrels. Epistatic effects play a central role in DeNovoTIMs stabilization. DeNovoTIMs navigate a previously uncharted region of the stability landscape.
The ability to design stable proteins with custom-made functions is a major goal in biochemistry with practical relevance for our environment and society. Understanding and manipulating protein stability provide crucial information on the molecular determinants that modulate structure and stability, and expand the applications of de novo proteins. Since the (β/⍺)8-barrel or TIM-barrel fold is one of the most common functional scaffolds, in this work we designed a collection of stable de novo TIM barrels (DeNovoTIMs), using a computational fixed-backbone and modular approach based on improved hydrophobic packing of sTIM11, the first validated de novo TIM barrel, and subjected them to a thorough folding analysis. DeNovoTIMs navigate a region of the stability landscape previously uncharted by natural TIM barrels, with variations spanning 60 degrees in melting temperature and 22 kcal per mol in conformational stability throughout the designs. Significant non-additive or epistatic effects were observed when stabilizing mutations from different regions of the barrel were combined. The molecular basis of epistasis in DeNovoTIMs appears to be related to the extension of the hydrophobic cores. This study is an important step towards the fine-tuned modulation of protein stability by design.
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Affiliation(s)
- Sergio Romero-Romero
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico; Department of Biochemistry, University of Bayreuth, 95447 Bayreuth, Germany
| | - Miguel Costas
- Laboratorio de Biofisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
| | - Daniel-Adriano Silva Manzano
- Department of Biochemistry, University of Washington, 98195 Seattle, USA; Institute for Protein Design, University of Washington, 98195 Seattle, USA
| | - Sina Kordes
- Department of Biochemistry, University of Bayreuth, 95447 Bayreuth, Germany
| | - Erendira Rojas-Ortega
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
| | - Cinthya Tapia
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
| | - Yasel Guerra
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
| | | | - Adela Rodríguez-Romero
- Instituto de Química, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
| | - David Baker
- Department of Biochemistry, University of Washington, 98195 Seattle, USA; Institute for Protein Design, University of Washington, 98195 Seattle, USA.
| | - Birte Höcker
- Department of Biochemistry, University of Bayreuth, 95447 Bayreuth, Germany.
| | - D Alejandro Fernández-Velasco
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico.
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42
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El Harrar T, Frieg B, Davari MD, Jaeger KE, Schwaneberg U, Gohlke H. Aqueous ionic liquids redistribute local enzyme stability via long-range perturbation pathways. Comput Struct Biotechnol J 2021; 19:4248-4264. [PMID: 34429845 PMCID: PMC8355836 DOI: 10.1016/j.csbj.2021.07.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 01/25/2023] Open
Abstract
Ionic liquids (IL) and aqueous ionic liquids (aIL) are attractive (co-)solvents for biocatalysis due to their unique properties. On the other hand, the incubation of enzymes in IL or aIL often reduces enzyme activity. Recent studies proposed various aIL-induced effects to explain the reduction, classified as direct effects, e.g., local dehydration or competitive inhibition, and indirect effects, e.g., structural perturbations or disturbed catalytic site integrity. However, the molecular origin of indirect effects has largely remained elusive. Here we show by multi-μs long molecular dynamics simulations, free energy computations, and rigidity analyses that aIL favorably interact with specific residues of Bacillus subtilis Lipase A (BsLipA) and modify the local structural stability of this model enzyme by inducing long-range perturbations of noncovalent interactions. The perturbations percolate over neighboring residues and eventually affect the catalytic site and the buried protein core. Validation against a complete experimental site saturation mutagenesis library of BsLipA (3620 variants) reveals that the residues of the perturbation pathways are distinguished sequence positions where substitutions highly likely yield significantly improved residual activity. Our results demonstrate that identifying these perturbation pathways and specific IL ion-residue interactions there effectively predicts focused variant libraries with improved aIL tolerance.
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Affiliation(s)
- Till El Harrar
- Institute of Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
- John-von-Neumann-Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Benedikt Frieg
- John-von-Neumann-Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Mehdi D. Davari
- Institute of Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, 52428 Jülich, Germany
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Ulrich Schwaneberg
- Institute of Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
- DWI – Leibniz Institute for Interactive Materials e.V., 52074 Aachen, Germany
| | - Holger Gohlke
- John-von-Neumann-Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
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43
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Jain K, Salamat-Miller N, Taylor K. Freeze-thaw characterization process to minimize aggregation and enable drug product manufacturing of protein based therapeutics. Sci Rep 2021; 11:11332. [PMID: 34059716 PMCID: PMC8166975 DOI: 10.1038/s41598-021-90772-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 05/04/2021] [Indexed: 11/29/2022] Open
Abstract
Physical instabilities of proteins in the form of protein aggregation continue to be a major challenge in the development of protein drug candidates. Aggregation can occur during different stages of product lifecycle such as freeze–thaw, manufacturing, shipping, and storage, and can potentially delay commercialization of candidates. A lack of clear understanding of the underlying mechanism(s) behind protein aggregation and the potential immunogenic reactions renders the presence of aggregates in biotherapeutic products undesirable. Understanding and minimizing aggregation can potentially reduce immunogenic responses and make protein therapeutics safer. Therefore, it is imperative to identify, understand, and control aggregation during early formulation development and develop reliable and orthogonal analytical methodologies to detect and monitor levels of aggregation. Freezing and thawing are typical steps involved in the manufacturing of drug product and could result in complex physical and chemical changes, which in turn could potentially cause protein aggregation. This study provides a systematic approach in understanding and selecting the ideal freeze–thaw conditions for manufacturing of protein-based therapeutics. It identifies the importance of balancing different excipients with an overall goal of sufficiently reducing or eliminating aggregation and developing a stable and scalable formulation. The results demonstrated that the freeze–thaw damage of mAb-1 in aqueous solutions was significantly reduced by identification of optimal freeze–thaw conditions using first a small-scale model with subsequent at-scale verifications. The work provides a framework for successful transfer of drug product manufacturing process from small-scale to the manufacturing scale production environment especially for molecules that are susceptible to freeze–thaw induced degradations.
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Affiliation(s)
- Keethkumar Jain
- Takeda Pharmaceutical Company Limited, 200 Shire Way, Lexington, MA, 02421, USA.
| | | | - Katherine Taylor
- Takeda Pharmaceutical Company Limited, 200 Shire Way, Lexington, MA, 02421, USA
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Harish B, Gillilan RE, Zou J, Wang J, Raleigh DP, Royer CA. Protein unfolded states populated at high and ambient pressure are similarly compact. Biophys J 2021; 120:2592-2598. [PMID: 33961866 DOI: 10.1016/j.bpj.2021.04.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/23/2021] [Accepted: 04/29/2021] [Indexed: 10/21/2022] Open
Abstract
The relationship between the dimensions of pressure-unfolded states of proteins compared with those at ambient pressure is controversial; resolving this issue is related directly to the mechanisms of pressure denaturation. Moreover, a significant pressure dependence of the compactness of unfolded states would complicate the interpretation of folding parameters from pressure perturbation and make comparison to those obtained using alternative perturbation approaches difficult. Here, we determined the compactness of the pressure-unfolded state of a small, cooperatively folding model protein, CTL9-I98A, as a function of temperature. This protein undergoes both thermal unfolding and cold denaturation, and the temperature dependence of the compactness at atmospheric pressure is known. High-pressure small angle x-ray scattering studies, yielding the radius of gyration and high-pressure diffusion ordered spectroscopy NMR experiments, yielding the hydrodynamic radius were carried out as a function of temperature at 250 MPa, a pressure at which the protein is unfolded. The radius of gyration values obtained at any given temperature at 250 MPa were similar to those reported previously at ambient pressure, and the trends with temperature are similar as well, although the pressure-unfolded state appears to undergo more pronounced expansion at high temperature than the unfolded state at atmospheric pressure. At 250 MPa, the compaction of the unfolded chain was maximal between 25 and 30°C, and the chain expanded upon both cooling and heating. These results reveal that the pressure-unfolded state of this protein is very similar to that observed at ambient pressure, demonstrating that pressure perturbation represents a powerful approach for observing the unfolded states of proteins under otherwise near-native conditions.
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Affiliation(s)
| | | | - Junjie Zou
- Department of Chemistry, Stony Brook University, Stony Brook, New York; Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York
| | - Jinqiu Wang
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York
| | - Daniel P Raleigh
- Department of Chemistry, Stony Brook University, Stony Brook, New York; Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York
| | - Catherine A Royer
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York.
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45
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Kumar S, Deshpande PA. Structural and thermodynamic analysis of factors governing the stability and thermal folding/unfolding of SazCA. PLoS One 2021; 16:e0249866. [PMID: 33857217 PMCID: PMC8049272 DOI: 10.1371/journal.pone.0249866] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 03/19/2021] [Indexed: 01/23/2023] Open
Abstract
Molecular basis of protein stability at different temperatures is a fundamental problem in protein science that is substantially far from being accurately and quantitatively solved as it requires an explicit knowledge of the temperature dependence of folding free energy of amino acid residues. In the present study, we attempted to gain insights into the thermodynamic stability of SazCA and its implications on protein folding/unfolding. We report molecular dynamics simulations of water solvated SazCA in a temperature range of 293-393 K to study the relationship between the thermostability and flexibility. Our structural analysis shows that the protein maintains the highest structural stability at 353 K and the protein conformations are highly flexible at temperatures above 353 K. Larger exposure of hydrophobic surface residues to the solvent medium for conformations beyond 353 K were identified from H-bond analysis. Higher number of secondary structure contents exhibited by SazCA at 353 K corroborated the conformations at 353 K to exhibit the highest thermal stability. The analysis of thermodynamics of protein stability revealed that the conformations that denature at higher melting temperatures tend to have greater maximum thermal stability. Our analysis shows that 353 K conformations have the highest melting temperature, which was found to be close to the experimental optimum temperature. The enhanced protein stability at 353 K due the least value of heat capacity at unfolding suggested an increase in folding. Comparative Gibbs free energy analysis and funnel shaped energy landscape confirmed a transition in folding/unfolding pathway of SazCA at 353 K.
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Affiliation(s)
- Shashi Kumar
- Quantum and Molecular Engineering Laboratory, Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Parag A. Deshpande
- Quantum and Molecular Engineering Laboratory, Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, India
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46
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Priyadarsini A, Mallik BS. Insignificant Effect of Temperature on the Structure and Angular Jumps of Water near a Hydrophobic Cation. ACS OMEGA 2021; 6:8356-8364. [PMID: 33817496 PMCID: PMC8015100 DOI: 10.1021/acsomega.1c00091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/15/2021] [Indexed: 05/12/2023]
Abstract
The ambiguity in the behavior of water molecules around hydrophobic solutes is a matter of interest for many studies. Motivated by the earlier results on the dynamics of water molecules around tetramethylammonium (TMA) cation, we present the effect of temperature on the structure and angular jumps of water due to hydrophobicity using first principles molecular dynamics simulations. The average intermolecular distance between the central oxygen and four nearest neighbors is found to be the highest for water molecules in the solvation shell of TMA at 400 K, followed by the same at 330 K. The hydrogen bond (HB) donor-acceptor count, HB per water molecule, and tetrahedral order parameter suggests the loss of tetrahedrality in the solvation shell. Elevated temperature affects the tetrahedral parameter in local regions. The HB jump mechanism is studied for methyl hydrogen and water molecules in the solvation shell. Observations hint at the presence of dangling water molecules in the vicinity of the hydrophobic cation, and no evidence is found for the enhanced structural ordering of nearby water molecules.
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47
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ElKassas K, Chullipalliyalil K, McAuliffe M, Vucen S, Crean A. Fluorescence spectroscopy for the determination of reconstitution time of an in-vial lyophilised product. Int J Pharm 2021; 597:120368. [PMID: 33561500 DOI: 10.1016/j.ijpharm.2021.120368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/01/2021] [Accepted: 02/04/2021] [Indexed: 12/18/2022]
Abstract
Lyophilisation is a prominent technique used to create stabilised, dried forms of biopharmaceutical formulations. Reconstitution of lyophilised parenteral formulations is a key step prior to patient administration. The accurate determination of reconstitution time is a necessity to aid formulation development and support product quality control. Traditional methods for quantifying reconstitution time involve the visual identification of the endpoint, which has led to variable values reported across studies. In this work, the use of ultra-violet (UV) excited fluorescence spectroscopy as an alternative to the visual quantification of the reconstitution time was investigated. Spectrographic information was collected via a bespoke setup that allowed the measurement of the reconstitution time in a standard sealed lyophilisation vial. The spectra were analysed via principal component analysis (PCA) to obtain a time-based representation of the changes in a reconstituting formulation. The analysis was followed by the identification of an endpoint using three techniques ranging from fully automated to manual with regards to the required level of user input. At high protein concentration, the variability of the reconstitution time measurements was reduced from 80.4% relative standard deviation obtained via the traditional method to 8.2% for the instrumental method presented in.
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Affiliation(s)
- Khaled ElKassas
- SSPC Centre for Pharmaceutical Research, School of Pharmacy, University College Cork, T12 YT20, Ireland
| | | | - Michael McAuliffe
- Centre for Advanced Photonics & Process Analysis, Munster Technological University Cork, T12P928, Ireland
| | - Sonja Vucen
- SSPC Centre for Pharmaceutical Research, School of Pharmacy, University College Cork, T12 YT20, Ireland
| | - Abina Crean
- SSPC Centre for Pharmaceutical Research, School of Pharmacy, University College Cork, T12 YT20, Ireland
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48
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Liu F, Cai Y, Wang H, Yang X, Zhao H. Polymerization-induced proteinosome formation. J Mater Chem B 2021; 9:1406-1413. [PMID: 33464259 DOI: 10.1039/d0tb02635b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In recent years, the fabrication of well-organized proteinosomes has been a popular topic due to the potential applications of the structures in materials science and nanotechnology. A big challenge in the fabrication of proteinosomes is to maintain the structures and the functionalities of proteins on the proteinosomes. In this research, a new concept of polymerization-induced formation of proteinosomes is proposed. In thermal dispersion polymerization of N-isopropyl acrylamide (NIPAM) in the presence of bovine serum albumin (BSA), the growing PNIPAM chains experience phase transition from hydrated coils to dehydrated globules, and the dehydrated PNIPAM chains have hydrophobic interaction with BSA, leading to the formation of hollow proteinosomes. Kinetics studies indicate that there is a transition from the homogeneous polymerization of NIPAM in solution to the heterogeneous polymerization in the proteinosomes. Transmission electron microscopy, atomic force microscopy, confocal laser scanning microscopy and dynamic light scattering all demonstrate the formation of hollow structures. The results of circular dichroism spectroscopy indicate that the secondary structure of BSA remains unchanged in the polymerization process. The formation of proteinosomes is reversible. Upon cooling of the solution to a temperature below the phase transition temperature of PNIPAM, the proteinosomes are dissociated due to the absence of the hydrophobic interaction. The proteinosomes can be used in the encapsulation of hydrophilic compounds in aqueous solution. In this research, not only BSA but also ovalbumin (OVA) is used as a model protein for the fabrication of proteinosomes by the polymerization-induced approach.
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Affiliation(s)
- Fang Liu
- College of Chemistry and Key Laboratory of Functional Polymer Materials of the Ministry of Education, Nankai University, Weijing Road #94, Tianjin 300071, China.
| | - Yaqian Cai
- College of Chemistry and Key Laboratory of Functional Polymer Materials of the Ministry of Education, Nankai University, Weijing Road #94, Tianjin 300071, China.
| | - Huan Wang
- College of Chemistry and Key Laboratory of Functional Polymer Materials of the Ministry of Education, Nankai University, Weijing Road #94, Tianjin 300071, China.
| | - Xinlin Yang
- College of Chemistry and Key Laboratory of Functional Polymer Materials of the Ministry of Education, Nankai University, Weijing Road #94, Tianjin 300071, China.
| | - Hanying Zhao
- College of Chemistry and Key Laboratory of Functional Polymer Materials of the Ministry of Education, Nankai University, Weijing Road #94, Tianjin 300071, China.
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49
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Meyer RM, Berger L, Nerkamp J, Scheler S, Nehring S, Friess W. Identification of monoclonal antibody variants involved in aggregate formation - Part 2: Hydrophobicity variants. Eur J Pharm Biopharm 2021; 160:134-142. [PMID: 33524536 DOI: 10.1016/j.ejpb.2021.01.006] [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: 10/26/2020] [Revised: 01/08/2021] [Accepted: 01/13/2021] [Indexed: 11/29/2022]
Abstract
Monoclonal antibodies (mAbs) are valuable tools both in therapy and in diagnostic. Their tendency to aggregate is a serious concern. Since a mAb drug substance (DS) is composed of different variants, it is important for manufacturers to know the behavior and stability not only of the mAb as a whole, but also of the variants contained in the product. We present a method to separate hydrophobicity variants of a mAb and subsequently analyzed these variants for stability and aggregation propensity. We identified a potentially aggregation prone hydrophilic variant which is interrelated with another previously identified aggregation prone acidic charge variant. Additionally, we assessed the risk posed by the aggregation prone variant to the DS by spiking hydrophobicity variants into DS and did not observe an enhanced aggregation propensity. Thus we present an approach to separate, characterize and analyze the criticality of aggregation prone variants in protein DS which is a step forward to further assure drug safety.
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Affiliation(s)
- Robina M Meyer
- Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, University of Munich, Butenandtstr. 5, 81377 Munich, Germany
| | - Lukas Berger
- Sandoz Biopharmaceutics, Biochemiestr. 10, 6336 Langkampfen, Austria
| | - Joerg Nerkamp
- Sandoz Biopharmaceutics, Biochemiestr. 10, 6336 Langkampfen, Austria
| | - Stefan Scheler
- Sandoz Biopharmaceutics, Biochemiestr. 10, 6336 Langkampfen, Austria
| | - Sebastian Nehring
- Sandoz Biopharmaceutics, Biochemiestr. 10, 6336 Langkampfen, Austria
| | - Wolfgang Friess
- Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, University of Munich, Butenandtstr. 5, 81377 Munich, Germany.
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50
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Lubin JH, Zardecki C, Dolan EM, Lu C, Shen Z, Dutta S, Westbrook JD, Hudson BP, Goodsell DS, Williams JK, Voigt M, Sarma V, Xie L, Venkatachalam T, Arnold S, Alvarado LHA, Catalfano K, Khan A, McCarthy E, Staggers S, Tinsley B, Trudeau A, Singh J, Whitmore L, Zheng H, Benedek M, Currier J, Dresel M, Duvvuru A, Dyszel B, Fingar E, Hennen EM, Kirsch M, Khan AA, Labrie-Cleary C, Laporte S, Lenkeit E, Martin K, Orellana M, de la Campa MOA, Paredes I, Wheeler B, Rupert A, Sam A, See K, Zapata SS, Craig PA, Hall BL, Jiang J, Koeppe JR, Mills SA, Pikaart MJ, Roberts R, Bromberg Y, Hoyer JS, Duffy S, Tischfield J, Ruiz FX, Arnold E, Baum J, Sandberg J, Brannigan G, Khare SD, Burley SK. Evolution of the SARS-CoV-2 proteome in three dimensions (3D) during the first six months of the COVID-19 pandemic. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020. [PMID: 33299989 DOI: 10.1101/2020.12.01.406637] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Three-dimensional structures of SARS-CoV-2 and other coronaviral proteins archived in the Protein Data Bank were used to analyze viral proteome evolution during the first six months of the COVID-19 pandemic. Analyses of spatial locations, chemical properties, and structural and energetic impacts of the observed amino acid changes in >48,000 viral proteome sequences showed how each one of the 29 viral study proteins have undergone amino acid changes. Structural models computed for every unique sequence variant revealed that most substitutions map to protein surfaces and boundary layers with a minority affecting hydrophobic cores. Conservative changes were observed more frequently in cores versus boundary layers/surfaces. Active sites and protein-protein interfaces showed modest numbers of substitutions. Energetics calculations showed that the impact of substitutions on the thermodynamic stability of the proteome follows a universal bi-Gaussian distribution. Detailed results are presented for six drug discovery targets and four structural proteins comprising the virion, highlighting substitutions with the potential to impact protein structure, enzyme activity, and functional interfaces. Characterizing the evolution of the virus in three dimensions provides testable insights into viral protein function and should aid in structure-based drug discovery efforts as well as the prospective identification of amino acid substitutions with potential for drug resistance.
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