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Hour C, Chuon K, Song MC, Shim JG, Cho SG, Kang KW, Kim JH, Jung KH. Unveiling the critical role of K + for xanthorhodopsin expression in E. coli. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2024; 258:112976. [PMID: 39002191 DOI: 10.1016/j.jphotobiol.2024.112976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 06/19/2024] [Accepted: 07/01/2024] [Indexed: 07/15/2024]
Abstract
Xanthorhodopsin (XR), a retinal-binding 7-transmembrane protein isolated from the eubacterium Salinibacter ruber, utilizes two chromophores (retinal and salinixanthin (SAL)) as an outward proton pump and energy-donating carotenoid. However, research on XR has been impeded owing to limitations in achieving heterogeneous expression of stable forms and high production levels of both wild-type and mutants. We successfully expressed wild-type and mutant XRs in Escherichia coli in the presence of K+. Achieving XR expression requires significant K+ and a low inducer concentration. In particular, we highlight the significance of Ser-159 in helix E located near Gly-156 (a carotenoid-binding position) as a critical site for XR expression. Our findings indicate that replacing Ser-159 with a smaller amino acid, alanine, can enhance XR expression in a manner comparable to K+, implying that Ser-159 poses a steric hindrance for pigment formation in XR. In the presence of K+, the proton pumping and photocycle of the wild-type and mutants were characterized and compared; the wild-type result suggests similar properties to the first reported XR isolation from the S. ruber membrane fraction. We propose that the K+ gradient across the cell membrane of S. ruber serves to uphold the membrane potential of the organism and plays a role in the expression of proteins, such as XR, as demonstrated in our study. Our findings deepen the understanding of adaptive protein expression, particularly in halophilic organisms. We highlight salt selection as a promising strategy for improving protein yield and functionality.
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Affiliation(s)
- Chenda Hour
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea
| | - Kimleng Chuon
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea
| | - Myung-Chul Song
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea
| | - Jin-Gon Shim
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea
| | - Shin-Gyu Cho
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea; Research Institute for Basic Science, Sogang University, Seoul, Republic of Korea
| | - Kun-Wook Kang
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea
| | - Ji-Hyun Kim
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea
| | - Kwang-Hwan Jung
- Department of Life Science and Institute of Biological Interfaces, Sogang University, Seoul, South Korea.
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2
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Benrezkallah D. Molecular dynamics simulations at high temperatures of the Aeropyrum pernix L7Ae thermostable protein: Insight into the unfolding pathway. J Mol Graph Model 2024; 127:108700. [PMID: 38183846 DOI: 10.1016/j.jmgm.2023.108700] [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: 09/07/2023] [Revised: 11/27/2023] [Accepted: 12/19/2023] [Indexed: 01/08/2024]
Abstract
Most life forms on earth live at temperatures below 50 °C. Within these organisms are proteins that form the three-dimensional structures essential to their biological activity and function. However, some thermophilic life forms can resist higher temperatures and have corresponding adaptations to preserve protein function at these high temperatures. Among the structural factors responsible for this resistance of thermophilic proteins to high temperatures is the presence of additional hydrogen bonds in the thermophilic proteins, which means that the structure of the protein is more resistant to unfolding. Similarly, thermostable proteins are rich in structure-stabilizing salt bridges and/or disulfide bridges. In this context, we perform multiple replica molecular dynamics simulations at different temperatures on the Aeropyrum pernix (L7Ae) protein (from the crenarchaeal species A. pernix), known for its high melting temperature, and this in the aim to elucidate the structural factors responsible for its high thermostability. The results reveal that between the most sensitive regions of the protein to the increase of temperature are the loops L1, and L5, which surround the hydrophobic core region of the protein, besides the loop L9, and the C-terminal α5 region. This latter is the longer alpha helix of the protein secondary structure motifs and it is the first to be denaturated at 450 K, while the rest of the protein secondary structure motifs at this temperature were intact. The mechanism of unfolding that follows this protein at 550 K is similar to other thermophile proteins found in literature, with the opening of the loops that surround the hydrophobic core of the protein. So, the latter is completely exposed to the solvent, and partially denatured. The total denaturation process of the protein takes an average time of 40 ns to be achieved. Our investigation also shows that all the calculated salt bridges, with distances less than or equal to 6 A°, are on the periphery part of the protein, exposed to the solvent. However, the hydrophobic core of the protein is not involved in the formation of salt bridges, but rather with formation of some important hydrogen bondings that still persist even at 450 K. So, optimizing hydrogen bonding, near or within the core region, at high temperatures is a strategy that follows this thermostable protein to protect its hydrophobic core from denaturation, and ensure the thermal stability of the protein.
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Affiliation(s)
- Djamila Benrezkallah
- Department of Basic Teachings in Sciences and Technologies (EBST), Faculty of Technology, Djillali Liabes University, Ben M'Hidi BP 89, Sidi Bel Abbes 22000, Algeria; LCPM Laboratory, Chemistry Department, Faculty of Exact and Applied Sciences, University Oran 1 Ahmed Ben Bella, El Mnaouer BP 1524, Oran 31000, Algeria.
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3
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Wei Z, Rolle MW, Camesano TA. Characterization of LL37 Binding to Collagen through Peptide Modification with a Collagen-Binding Domain. ACS OMEGA 2023; 8:35370-35381. [PMID: 37779975 PMCID: PMC10536065 DOI: 10.1021/acsomega.3c05328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Accepted: 08/31/2023] [Indexed: 10/03/2023]
Abstract
Collagen-based biomaterials loaded with antimicrobial peptides (AMPs) present a promising approach for promoting wound healing while providing protection against infections. In our previous work, we modified the AMP LL37 by incorporating a collagen-binding domain (cCBD) as an anchoring unit for collagen-based wound dressings. We demonstrated that cCBD-modified LL37 (cCBD-LL37) exhibited improved retention on collagen after washing with PBS. However, the binding mechanism of cCBD-LL37 to collagen remained to be elucidated. In this study, we found that cCBD-LL37 showed a slightly higher affinity for collagen compared to LL37. Our results indicated that cCBD inhibited cCBD-LL37 binding to collagen but did not fully eliminate the binding. This suggests that cCBD-LL37 binding to collagen may involve more than just one-site-specific binding through the collagen-binding domain, with non-specific interactions also playing a role. Electrostatic studies revealed that both LL37 and cCBD-LL37 interact with collagen via long-range electrostatic forces, initiating low-affinity binding that transitions to close-range or hydrophobic interactions. Circular dichroism analysis showed that cCBD-LL37 exhibited enhanced structural stability compared to LL37 under varying ionic strengths and pH conditions, implying potential improvements in antimicrobial activity. Moreover, we demonstrated that the release of LL37 and cCBD-LL37 into the surrounding medium was influenced by the electrostatic environment, but cCBD could enhance the retention of peptide on collagen scaffolds. Collectively, these results provide important insights into cCBD-modified AMP-binding mechanisms and suggest that the addition of cCBD may enhance peptide structural stability and retention under varying electrostatic conditions.
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Affiliation(s)
- Ziqi Wei
- Department
of Chemical Engineering, Worcester Polytechnic
Institute, 100 Institute Road, Worcester, Massachusetts 01609, United States
| | - Marsha W. Rolle
- Department
of Biomedical Engineering, Worcester Polytechnic
Institute, 100 Institute Road, Worcester, Massachusetts 01609, United States
| | - Terri A. Camesano
- Department
of Chemical Engineering, Worcester Polytechnic
Institute, 100 Institute Road, Worcester, Massachusetts 01609, United States
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Chakraborty S, Mandal K, Ramakrishnan R. Understanding the Role of Intramolecular Ion-Pair Interactions in Conformational Stability Using an Ab Initio Thermodynamic Cycle. J Phys Chem B 2023; 127:648-660. [PMID: 36638237 DOI: 10.1021/acs.jpcb.2c06803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Intramolecular ion-pair interactions yield shape and functionality to many molecules. With proper orientation, these interactions overcome steric factors and are responsible for the compact structures of several peptides. In this study, we present a thermodynamic cycle based on isoelectronic and alchemical mutation to estimate the intramolecular ion-pair interaction energy. We determine these energies for 26 benchmark molecules with common ion-pair combinations and compare them with results obtained using intramolecular symmetry-adapted perturbation theory. For systems with long linkers, the ion-pair energies evaluated using both approaches deviate by less than 2.5% in the vacuum phase. The thermodynamic cycle based on density functional theory facilitates calculations of salt-bridge interactions in model tripeptides with continuum/microsolvation modeling and four large peptides: 1EJG (crambin), 1BDK (bradykinin), 1L2Y (a mini-protein with a tryptophan cage), and 1SCO (a toxin from the scorpion venom).
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Affiliation(s)
| | - Kalyaneswar Mandal
- Tata Institute of Fundamental Research Hyderabad, Hyderabad500046, India
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Veiko VP, Antipov AN, Mordkovich NN, Okorokova NA, Safonova TN, Polyakov KM. The Thermostability of Nucleoside Phosphorylases from Prokaryotes. I. The Role of the Primary Structure of the N-terminal fragment of the Protein in the Thermostability of Uridine Phosphorylases. APPL BIOCHEM MICRO+ 2022. [DOI: 10.1134/s0003683822060151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
AbstractMutant uridine phosphorylase genes from Shewanella oneidensis MR-1 (S. oneidensis) were constructed by site-directed mutagenesis and strains-producers of the corresponding recombinant (F5I and F5G) proteins were obtained on the basis of Escherichia coli cells. The mutant proteins were purified and their physicochemical and enzymatic properties were studied. It was shown that the N-terminal fragment of uridine phosphorylase plays an important role in the thermal stabilization of the enzyme as a whole. The role of the aminoacid (a.a.) residue phenylalanine (F5) in the formation of thermotolerance of uridine phosphorylases from gamma-proteobacteria was revealed.
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Structural Analysis and Construction of a Thermostable Antifungal Chitinase. Appl Environ Microbiol 2022; 88:e0065222. [PMID: 35652665 DOI: 10.1128/aem.00652-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chitin is a biopolymer of N-acetyl-d-glucosamine with β-1,4-bond and is the main component of arthropod exoskeletons and the cell walls of many fungi. Chitinase (EC 3.2.1.14) is an enzyme that hydrolyzes the β-1,4-bond in chitin and degrades chitin into oligomers. It has been found in a wide range of organisms. Chitinase from Gazyumaru (Ficus microcarpa) latex exhibits antifungal activity by degrading chitin in the cell wall of fungi and is expected to be used in medical and agricultural fields. However, the enzyme's thermostability is an important factor; chitinase is not thermostable enough to maintain its activity under the actual application conditions. In addition to the fact that thermostable chitinases exhibiting antifungal activity can be used under various conditions, they have some advantages for the production process and long-term preservation, which are highly demanded in industrial use. We solved the crystal structure of chitinase to explore the target sites to improve its thermostability. We rationally introduced proline residues, a disulfide bond, and salt bridges in the chitinase using protein-engineering methods based on the crystal structure and sequence alignment among other chitinases. As a result, we successfully constructed the thermostable mutant chitinases rationally with high antifungal and specific activities. The results provide a useful strategy to enhance the thermostability of this enzyme family. IMPORTANCE We solved the crystal structure of the chitinase from Gazyumaru (Ficus microcarpa) latex exhibiting antifungal activity. Furthermore, we demonstrated that the thermostable mutant enzyme with a melting temperature (Tm) 6.9°C higher than wild type (WT) and a half-life at 60°C that is 15 times longer than WT was constructed through 10 amino acid substitutions, including 5 proline residues substitutions, making disulfide bonding, and building a salt bridge network in the enzyme. These mutations do not affect its high antifungal activity and chitinase activity, and the principle for the construction of the thermostable chitinase was well explained by its crystal structure. Our results provide a useful strategy to enhance the thermostability of this enzyme family and to use the thermostable mutant as a seed for antifungal agents for practical use.
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Abbasi Kheirabadi M, Saffar B, Hemmati R, Mortazavi M. Thermally stable and acidic pH tolerant mutant phytases with high catalytic efficiency from Yersinia intermedia for potential application in feed industries. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:33713-33724. [PMID: 35029822 DOI: 10.1007/s11356-022-18578-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
Heat- and pH-stable phytase efficiently hydrolyzes phytic acid. In this research, heat- and pH-stable mutant phytases, T83R, L287R, and T83R/L287R were generated by site-directed mutagenesis from Yersinia intermedia. After the induction and expression of recombinant wild-type and mutant phytases in E. coli BL21, the enzymes were purified using nickel sepharose affinity chromatography, and characterized kinetically and thermodynamically using spectroscopy methods. The mutants showed optimum activity at pH 5.15 and 55-61 °C. The catalytic efficiencies of T83R, L287R, T83R/L287R, and wild-type phytases were calculated to be 2941, 29346, 4906, and 6917 mmol/L-1s-1, respectively. Moreover, after the incubation of T83R, L287R, wild-type, and T83R/ L287R phytases at 100 °C for 1 h, the enzymes retained 22, 5, 4, and 2% of their initial activities, respectively. In addition, T83R, T83R/L287R, L287R, and wild-type phytases retained 82, 44, 16 as well as 11% of their initial activities after 1 h at pH 5.15, respectively. Among these mutants, T83R mutant showed 18% increase in thermal stability, 71% increase in pH stability, and +0.103 KJ/mole increase in ΔΔG, while the catalytic efficiency and ΔΔG value of L287R mutant increased by 4 times and +0.0903 KJ/mole, respectively. Thus, the mutants have the potential to be used in feed industries to increase the bioavailability of minerals while decreasing soil and water pollution.
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Affiliation(s)
| | - Behnaz Saffar
- Department of Genetics, Faculty of Basic Sciences, Shahrekord University, Shahrekord, Iran
| | - Roohullah Hemmati
- Department of Biology, Faculty of Basic Sciences, Shahrekord University, 88186-34141, Shahrekord, Iran.
- Biotechnology Research Institute, Shahrekord University, Shahrekord, Iran.
| | - Mojtaba Mortazavi
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
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Joshi JB, Priyadharshini R, Uthandi S. Glycosyl hydrolase 11 (xynA) gene with xylanase activity from thermophilic bacteria isolated from thermal springs. Microb Cell Fact 2022; 21:62. [PMID: 35428308 PMCID: PMC9013152 DOI: 10.1186/s12934-022-01788-3] [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: 07/18/2021] [Accepted: 03/29/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Hemicellulose is one of the copious polymer in lignocellulosic biomass (LCB). It is primarily composed of xylan linked by β-1,4 glycosidic bonds. Xylanase preferentially cleaves the β-1,4-glycosidic bonds in the xylan backbone resulting in complete hydrolysis of the biomass. Thermostable variants of glycoside hydrolases act as robust catalysts, not only in degradation but also during processing, to obtain specific carbohydrate-containing chemicals and materials (Ramasamy et al. in Madras Agric J 107(special):1. 10.29321/MAJ.2020.000382, 2020).
Results
The xylanase production by two thermophilic bacteria isolated from thermal springs was evaluated. In addition, the gene encoding this industrially vital enzyme was isolated and characterized, and its protein structure was analyzed. The thermophilic bacteria producing xylanases were isolated from augmented sawdust and banana fiber biomass from hot springs of Himachal Pradesh and identified as Bacillus subtilis VSDB5 and Bacillus licheniformis KBFB4 using 16S rRNA gene sequencing. The persistent xylanase activity revealed that the enzyme is secreted extracellularly with the maximum activity of 0.76 IU mL−1 and 1.0 IU mL−1 at 6 h and 12 h of growth by KBFB4 and VSDB5, respectively, under submerged fermentation. Both the strains exhibited the maximum activity at pH 6 and a temperature of 50 °C. The xylanases of KBFB4 and VSDB5 were thermostable and retained 40% of their activity at 60 °C after incubation for 30 min. Xylanase of VSDB5 had wide thermotolerance and retained 20% of its activity from 60 to 80 °C, whereas xylanase of KBFB4 showed wide alkali tolerance and retained 80% of its activity until pH 10. The xylanase (xynA)-encoding gene (650 bp) cloned from both the strains using specific primers showed 98 to 99% homology to β-1,4-endoxylanase gene. Further in silico analysis predicted that the xylanase protein, with a molecular weight of 23 kDa, had a high pI (9.44–9.65), which explained the alkaline nature of the enzyme and greater aliphatic index (56.29). This finding suggested that the protein is thermostable. Multiple sequence alignment and homology modeling of the protein sequence revealed that the gene product belonged to the GH11 family, indicating its possible application in bioconversion.
Conclusion
The strains B. subtilis VSDB5 and B. licheniformis KBFB4 obtained from hot springs of Himachal Pradesh produced potent and alkali-tolerant thermostable xylanases, which belong to the GH11 family. The enzyme can be supplemented in industrial applications for biomass conversion at high temperatures and pH (or in processes involving alkali treatment).
Graphical Abstract
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Improvement of FGF7 Thermal Stability by Introduction of Mutations in Close Vicinity to Disulfide Bond and Surface Salt Bridge. Int J Pept Res Ther 2022. [DOI: 10.1007/s10989-022-10394-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AbstractFibroblast Growth Factor 7 (FGF7), a growth factor specific to epithelial cells, has attracted attention as a therapeutic protein. However, FGF7 has a limitation in its use due to low protein stability. Here, the mutations were designed to increase the stability of FGF7 by analyzing its 3D structure and sequence of other FGFs. Palifermin, N-terminal truncated FGF7 is known to have improved stability and was used as control protein in our study. The K126 and K178 were substituted into glutamate to form salt bridge with the neighboring residue R175 respectively and A120C mutation was introduced in close vicinity to disulfide bond between C133 and C137. The data of Circular Dichroism (CD) showed that all mutant proteins tested had higher Tm value than Palifermin and Tm of A120C/K126E/K178E FGF7 mutant protein was 15.24 °C higher than that of Palifermin. The results of cell proliferation activity and soluble protein analyzed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) after 37 °C or 45 °C incubation exhibited that the stability of A120C mutant protein and A120C-including mutant proteins was improved. These results suggest that the mutation of amino acid in close vicinity to disulfide bond and the salt bridge at the surface of FGF7 enhanced thermal stability and make FGF7 more useful for pharmaceutical and cosmetical application.
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Lack of Charge Interaction in the Ion Binding Site Determines Anion Selectivity in the Sodium Bicarbonate Cotransporter NBCe1. Int J Mol Sci 2022; 23:ijms23010532. [PMID: 35008963 PMCID: PMC8745181 DOI: 10.3390/ijms23010532] [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: 11/17/2021] [Revised: 12/24/2021] [Accepted: 12/30/2021] [Indexed: 02/01/2023] Open
Abstract
The Na/HCO3 cotransporter NBCe1 is a member of SLC4A transporters that move HCO3− across cell membranes and regulate intracellular pH or transepithelial HCO3 transport. NBCe1 is highly selective to HCO3− and does not transport other anions; the molecular mechanism of anion selectivity is presently unclear. We previously reported that replacing Asp555 with a Glu (D555E) in NBCe1 induces increased selectivity to other anions, including Cl−. This finding is unexpected because all SLC4A transporters contain either Asp or Glu at the corresponding position and maintain a high selectivity to HCO3−. In this study, we tested whether the Cl− transport in D555E is mediated by an interaction between residues in the ion binding site. Human NBCe1 and mutant transporters were expressed in Xenopus oocytes, and their ability to transport Cl− was assessed by two-electrode voltage clamp. The results show that the Cl− transport is induced by a charge interaction between Glu555 and Lys558. The bond length between the two residues is within the distance for a salt bridge, and the ionic strength experiments confirm an interaction. This finding indicates that the HCO3− selectivity in NBCe1 is established by avoiding a specific charge interaction in the ion binding site, rather than maintaining such an interaction.
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11
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Van Wyk JC, Sewell BT, Danson MJ, Tsekoa TL, Sayed MF, Cowan DA. Engineering enhanced thermostability into the Geobacillus pallidus nitrile hydratase. Curr Res Struct Biol 2022; 4:256-270. [PMID: 36106339 PMCID: PMC9465369 DOI: 10.1016/j.crstbi.2022.07.002] [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: 03/10/2022] [Revised: 06/27/2022] [Accepted: 07/19/2022] [Indexed: 11/20/2022] Open
Abstract
Nitrile hydratases (NHases) are important biocatalysts for the enzymatic conversion of nitriles to industrially-important amides such as acrylamide and nicotinamide. Although thermostability in this enzyme class is generally low, there is not sufficient understanding of its basis for rational enzyme design. The gene expressing the Co-type NHase from the moderate thermophile, Geobacillus pallidus RAPc8 (NRRL B-59396), was subjected to random mutagenesis. Four mutants were selected that were 3 to 15-fold more thermostable than the wild-type NHase, resulting in a 3.4–7.6 kJ/mol increase in the activation energy of thermal inactivation at 63 °C. High resolution X-ray crystal structures (1.15–1.80 Å) were obtained of the wild-type and four mutant enzymes. Mutant 9E, with a resolution of 1.15 Å, is the highest resolution crystal structure obtained for a nitrile hydratase to date. Structural comparisons between the wild-type and mutant enzymes illustrated the importance of salt bridges and hydrogen bonds in enhancing NHase thermostability. These additional interactions variously improved thermostability by increased intra- and inter-subunit interactions, preventing cooperative unfolding of α-helices and stabilising loop regions. Some hydrogen bonds were mediated via a water molecule, specifically highlighting the significance of structured water molecules in protein thermostability. Although knowledge of the mutant structures makes it possible to rationalize their behaviour, it would have been challenging to predict in advance that these mutants would be stabilising. Random mutagenesis yields a 15-fold increase in nitrile hydratase thermostability. Salt bridges and hydrogen bonds improves nitrile hydratase thermostability. Water-mediated hydrogen bonds improves protein thermostability.
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12
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Kordes S, Romero-Romero S, Lutz L, Höcker B. A newly introduced salt bridge cluster improves structural and biophysical properties of de novo TIM barrels. Protein Sci 2021; 31:513-527. [PMID: 34865275 PMCID: PMC8820119 DOI: 10.1002/pro.4249] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/30/2021] [Accepted: 12/03/2021] [Indexed: 01/18/2023]
Abstract
Protein stability can be fine‐tuned by modifying different structural features such as hydrogen‐bond networks, salt bridges, hydrophobic cores, or disulfide bridges. Among these, stabilization by salt bridges is a major challenge in protein design and engineering since their stabilizing effects show a high dependence on the structural environment in the protein, and therefore are difficult to predict and model. In this work, we explore the effects on structure and stability of an introduced salt bridge cluster in the context of three different de novo TIM barrels. The salt bridge variants exhibit similar thermostability in comparison with their parental designs but important differences in the conformational stability at 25°C can be observed such as a highly stabilizing effect for two of the proteins but a destabilizing effect to the third. Analysis of the formed geometries of the salt bridge cluster in the crystal structures show either highly ordered salt bridge clusters or only single salt bridges. Rosetta modeling of the salt bridge clusters results in a good prediction of the tendency on stability changes but not the geometries observed in the three‐dimensional structures. The results show that despite the similarities in protein fold, the salt bridge clusters differently influence the structural and stability properties of the de novo TIM barrel variants depending on the structural background where they are introduced. PDB Code(s): 7OSU, 7OT7, 7OSV, 7OT8 and 7P12;
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Affiliation(s)
- Sina Kordes
- Department of Biochemistry, University of Bayreuth, Bayreuth, Germany
| | | | - Leonie Lutz
- Department of Biochemistry, University of Bayreuth, Bayreuth, Germany
| | - Birte Höcker
- Department of Biochemistry, University of Bayreuth, Bayreuth, Germany
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13
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Pras A, Houben B, Aprile FA, Seinstra R, Gallardo R, Janssen L, Hogewerf W, Gallrein C, De Vleeschouwer M, Mata‐Cabana A, Koopman M, Stroo E, de Vries M, Louise Edwards S, Kirstein J, Vendruscolo M, Falsone SF, Rousseau F, Schymkowitz J, Nollen EAA. The cellular modifier MOAG-4/SERF drives amyloid formation through charge complementation. EMBO J 2021; 40:e107568. [PMID: 34617299 PMCID: PMC8561633 DOI: 10.15252/embj.2020107568] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 08/27/2021] [Accepted: 09/01/2021] [Indexed: 11/09/2022] Open
Abstract
While aggregation-prone proteins are known to accelerate aging and cause age-related diseases, the cellular mechanisms that drive their cytotoxicity remain unresolved. The orthologous proteins MOAG-4, SERF1A, and SERF2 have recently been identified as cellular modifiers of such proteotoxicity. Using a peptide array screening approach on human amyloidogenic proteins, we found that SERF2 interacted with protein segments enriched in negatively charged and hydrophobic, aromatic amino acids. The absence of such segments, or the neutralization of the positive charge in SERF2, prevented these interactions and abolished the amyloid-promoting activity of SERF2. In protein aggregation models in the nematode worm Caenorhabditis elegans, protein aggregation and toxicity were suppressed by mutating the endogenous locus of MOAG-4 to neutralize charge. Our data indicate that MOAG-4 and SERF2 drive protein aggregation and toxicity by interactions with negatively charged segments in aggregation-prone proteins. Such charge interactions might accelerate primary nucleation of amyloid by initiating structural changes and by decreasing colloidal stability. Our study points at charge interactions between cellular modifiers and amyloidogenic proteins as potential targets for interventions to reduce age-related protein toxicity.
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Affiliation(s)
- Anita Pras
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Bert Houben
- VIB‐KU Leuven Center for Brain and Disease ResearchLeuvenBelgium
- Switch LaboratoryDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | - Francesco A Aprile
- Department of ChemistryCentre for Misfolding DiseasesUniversity of CambridgeCambridgeUK
- Present address:
Department of ChemistryMolecular Sciences Research HubImperial College LondonLondonUK
| | - Renée Seinstra
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Rodrigo Gallardo
- VIB‐KU Leuven Center for Brain and Disease ResearchLeuvenBelgium
- Switch LaboratoryDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- Present address:
Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsUK
| | - Leen Janssen
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Wytse Hogewerf
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Christian Gallrein
- Department of Molecular Physiology and Cell BiologyLeibniz Research Institute for Molecular Pharmacology im Forschungsverbund Berlin e.V. (FMP)BerlinGermany
| | - Matthias De Vleeschouwer
- VIB‐KU Leuven Center for Brain and Disease ResearchLeuvenBelgium
- Switch LaboratoryDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | - Alejandro Mata‐Cabana
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Mandy Koopman
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Esther Stroo
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Minke de Vries
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Samantha Louise Edwards
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
| | - Janine Kirstein
- Department of Molecular Physiology and Cell BiologyLeibniz Research Institute for Molecular Pharmacology im Forschungsverbund Berlin e.V. (FMP)BerlinGermany
- Faculty of Biology & ChemistryUniversity of BremenBremenGermany
| | - Michele Vendruscolo
- Department of ChemistryCentre for Misfolding DiseasesUniversity of CambridgeCambridgeUK
| | | | - Frederic Rousseau
- VIB‐KU Leuven Center for Brain and Disease ResearchLeuvenBelgium
- Switch LaboratoryDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | - Joost Schymkowitz
- VIB‐KU Leuven Center for Brain and Disease ResearchLeuvenBelgium
- Switch LaboratoryDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | - Ellen A A Nollen
- European Research Institute for the Biology of AgeingUniversity of GroningenUniversity Medical Centre GroningenGroningenThe Netherlands
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14
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Boucher L, Somani S, Negron C, Ma W, Jacobs S, Chan W, Malia T, Obmolova G, Teplyakov A, Gilliland GL, Luo J. Surface salt bridges contribute to the extreme thermal stability of an FN3-like domain from a thermophilic bacterium. Proteins 2021; 90:270-281. [PMID: 34405904 DOI: 10.1002/prot.26218] [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: 07/25/2020] [Revised: 03/08/2021] [Accepted: 08/02/2021] [Indexed: 12/27/2022]
Abstract
This study uses differential scanning calorimetry, X-ray crystallography, and molecular dynamics simulations to investigate the structural basis for the high thermal stability (melting temperature 97.5°C) of a FN3-like protein domain from thermophilic bacteria Thermoanaerobacter tengcongensis (FN3tt). FN3tt adopts a typical FN3 fold with a three-stranded beta sheet packing against a four-stranded beta sheet. We identified three solvent exposed arginine residues (R23, R25, and R72), which stabilize the protein through salt bridge interactions with glutamic acid residues on adjacent strands. Alanine mutation of the three arginine residues reduced melting temperature by up to 22°C. Crystal structures of the wild type (WT) and a thermally destabilized (∆Tm -19.7°C) triple mutant (R23L/R25T/R72I) were found to be nearly identical, suggesting that the destabilization is due to interactions of the arginine residues. Molecular dynamics simulations showed that the salt bridge interactions in the WT were stable and provided a dynamical explanation for the cooperativity observed between R23 and R25 based on calorimetry measurements. In addition, folding free energy changes computed using free energy perturbation molecular dynamics simulations showed high correlation with melting temperature changes. This work is another example of surface salt bridges contributing to the enhanced thermal stability of thermophilic proteins. The molecular dynamics simulation methods employed in this study may be broadly useful for in silico surface charge engineering of proteins.
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Affiliation(s)
- Lauren Boucher
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Sandeep Somani
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | | | - Wenting Ma
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Steven Jacobs
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Winnie Chan
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Thomas Malia
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Galina Obmolova
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Alexey Teplyakov
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Gary L Gilliland
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
| | - Jinquan Luo
- Janssen Research & Development, LLC, Spring House, Pennsylvania, USA
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15
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Li L, Li W, Gong J, Xu Y, Wu Z, Jiang Z, Cheng YS, Li Q, Ni H. An effective computational-screening strategy for simultaneously improving both catalytic activity and thermostability of α-l-rhamnosidase. Biotechnol Bioeng 2021; 118:3409-3419. [PMID: 33742693 DOI: 10.1002/bit.27758] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/04/2021] [Accepted: 03/18/2021] [Indexed: 12/21/2022]
Abstract
Catalytic efficiency and thermostability are the two most important characteristics of enzymes. However, it is always tough to improve both catalytic efficiency and thermostability of enzymes simultaneously. In the present study, a computational strategy with double-screening steps was proposed to simultaneously improve both catalysis efficiency and thermostability of enzymes; and a fungal α-l-rhamnosidase was used to validate the strategy. As the result, by molecular docking and sequence alignment analysis within the binding pocket, seven mutant candidates were predicted with better catalytic efficiency. By energy variety analysis, A355N, S356Y, and D525N among the seven mutant candidates were predicted with better thermostability. The expression and characterization results showed the mutant D525N had significant improvements in both enzyme activity and thermostability. Molecular dynamics simulations indicated that the mutations located within the 5 Å range of the catalytic domain, which could improve root mean squared deviation, electrostatic, Van der Waal interaction, and polar salvation values, and formed water bridge between the substrate and the enzyme. The study indicated that the computational strategy based on the binding energy, conservation degree and mutation energy analyses was effective to develop enzymes with better catalysis and thermostability, providing practical approach for developing industrial enzymes.
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Affiliation(s)
- Lijun Li
- College of Food and Biological Engineering, Jimei University, Xiamen, China.,Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, Xiamen, China.,Research Center of Food Biotechnology of Xiamen City, Xiamen, China
| | - Wenjing Li
- College of Food and Biological Engineering, Jimei University, Xiamen, China
| | - Jianye Gong
- College of Food and Biological Engineering, Jimei University, Xiamen, China
| | - Yanyan Xu
- Tan Kah Kee College, Xiamen University, Zhangzhou, China
| | - Zheyu Wu
- College of Food and Biological Engineering, Jimei University, Xiamen, China
| | - Zedong Jiang
- College of Food and Biological Engineering, Jimei University, Xiamen, China
| | - Yi-Sheng Cheng
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Qingbiao Li
- College of Food and Biological Engineering, Jimei University, Xiamen, China.,Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, Xiamen, China.,Research Center of Food Biotechnology of Xiamen City, Xiamen, China
| | - Hui Ni
- College of Food and Biological Engineering, Jimei University, Xiamen, China.,Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, Xiamen, China.,Research Center of Food Biotechnology of Xiamen City, Xiamen, China
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16
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Liu Y, Luo G, Ngo HH, Guo W, Zhang S. Advances in thermostable laccase and its current application in lignin-first biorefinery: A review. BIORESOURCE TECHNOLOGY 2020; 298:122511. [PMID: 31839492 DOI: 10.1016/j.biortech.2019.122511] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 11/26/2019] [Accepted: 11/27/2019] [Indexed: 06/10/2023]
Abstract
As the most abundant aromatic polymers on the Earth, lignin has great potential to produce biofuels and aromatic chemicals due to their high carbon content and low oxygen content. Lignin-first biorefinery methods have attracted increasing attention recently for their high-value of aromatic chemicals, and high biofuels productivity from lignocellulosic wastes. Thermostable laccase has proven to be an excellent alternative catalyst in degrading lignin for its versatile catalytic abilities under industrial conditions and pollution-free by-products. Thermostable laccases can be found in native extreme environments or modified by biologically based technologies such as gene recombination expression and enzyme direct evolution. This review demonstrated thermostable laccases and their application in lignin degradation. Future research should focus more on the investigation of the reaction of thermostable laccases with lignin substrates.
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Affiliation(s)
- Yi Liu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Gang Luo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Huu Hao Ngo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Wenshan Guo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Shicheng Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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17
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Timr S, Madern D, Sterpone F. Protein thermal stability. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 170:239-272. [PMID: 32145947 DOI: 10.1016/bs.pmbts.2019.12.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Proteins, in general, fold to a well-organized three-dimensional structure in order to function. The stability of this functional shape can be perturbed by external environmental conditions, such as temperature. Understanding the molecular factors underlying the resistance of proteins to the thermal stress has important consequences. First of all, it can aid the design of thermostable enzymes able to perform efficient catalysis in the high-temperature regime. Second, it is an essential brick of knowledge required to decipher the evolutionary pathways of life adaptation on Earth. Thanks to the development of atomistic simulations and ad hoc enhanced sampling techniques, it is now possible to investigate this problem in silico, and therefore provide support to experiments. After having described the methodological aspects, the chapter proposes an extended discussion on two problems. First, we focus on thermophilic proteins, a perfect model to address the issue of thermal stability and molecular evolution. Second, we discuss the issue of how protein thermal stability is affected by crowded in vivo-like conditions.
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Affiliation(s)
- Stepan Timr
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | | | - Fabio Sterpone
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France.
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18
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Ferreira PHB, Freitas FC, McCully ME, Slade GG, de Oliveira RJ. The Role of Electrostatics and Folding Kinetics on the Thermostability of Homologous Cold Shock Proteins. J Chem Inf Model 2020; 60:546-561. [PMID: 31910002 DOI: 10.1021/acs.jcim.9b00797] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Understanding which aspects contribute to the thermostability of proteins is a challenge that has persisted for decades, and it is of great relevance for protein engineering. Several types of interactions can influence the thermostability of a protein. Among them, the electrostatic interactions have been a target of particular attention. Aiming to explore how this type of interaction can affect protein thermostability, this paper investigated four homologous cold shock proteins from psychrophilic, mesophilic, thermophilic, and hyperthermophilic organisms using a set of theoretical methodologies. It is well-known that electrostatics as well as hydrophobicity are key-elements for the stabilization of these proteins. Therefore, both interactions were initially analyzed in the native structure of each protein. Electrostatic interactions present in the native structures were calculated with the Tanford-Kirkwood model with solvent accessibility, and the amount of hydrophobic surface area buried upon folding was estimated by measuring both folded and extended structures. On the basis of Energy Landscape Theory, the local frustration and the simplified alpha-carbon structure-based model were modeled with a Debye-Hückel potential to take into account the electrostatics and the effects of an implicit solvent. Thermodynamic data for the structure-based model simulations were collected and analyzed using the Weighted Histogram Analysis and Stochastic Diffusion methods. Kinetic quantities including folding times, transition path times, folding routes, and Φ values were also obtained. As a result, we found that the methods are able to qualitatively infer that electrostatic interactions play an important role on the stabilization of the most stable thermophilic cold shock proteins, showing agreement with the experimental data.
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Affiliation(s)
- Paulo Henrique Borges Ferreira
- Laboratório de Biofísica Teórica, Departamento de Física, Instituto de Ciências Exatas, Naturais e Educação , Universidade Federal do Triângulo Mineiro , Uberaba , Minas Gerais 38064200 , Brazil
| | - Frederico Campos Freitas
- Laboratório de Biofísica Teórica, Departamento de Física, Instituto de Ciências Exatas, Naturais e Educação , Universidade Federal do Triângulo Mineiro , Uberaba , Minas Gerais 38064200 , Brazil
| | - Michelle E McCully
- Department of Biology , Santa Clara University , Santa Clara , California 95050 , United States
| | - Gabriel Gouvêa Slade
- Laboratório de Biofísica Teórica, Departamento de Física, Instituto de Ciências Exatas, Naturais e Educação , Universidade Federal do Triângulo Mineiro , Uberaba , Minas Gerais 38064200 , Brazil
| | - Ronaldo Junio de Oliveira
- Laboratório de Biofísica Teórica, Departamento de Física, Instituto de Ciências Exatas, Naturais e Educação , Universidade Federal do Triângulo Mineiro , Uberaba , Minas Gerais 38064200 , Brazil
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19
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Kargar F, Mortazavi M, Torkzadeh-Mahani M, Lotfi S, Shakeri S. Evaluation of Luciferase Thermal Stability by Arginine Saturation in the Flexible Loops. CURR PROTEOMICS 2020. [DOI: 10.2174/1570164616666190320151005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
The firefly luciferase enzyme is widely used in protein engineering and diverse
areas of biotechnology, but the main problem with this enzyme is low-temperature stability. Previous
reports indicated that surface areas of thermostable proteins are rich in arginine, which increased
their thermal stability. In this study, this aspect of thermophilic proteins evaluated by mutations of surface
residues to Arg. Here, we report the construction, purification, and studying of these mutated luciferases.
Methods:
For mutagenesis, the QuikChange site-directed mutagenesis was used and the I108R,
T156R, and N177R mutant luciferases were created. In the following, the expression and purification
of wild-type and mutant luciferases were conducted and their kinetic and structural properties were analyzed.
To analyze the role of these Arg in these loops, the 3D models of these mutants’ enzymes were
constructed in the I-TASSER server and the exact situation of these mutants was studied by the
SPDBV and PyMOL software.
Results:
Overall, the optimum temperature of these mutated enzymes was not changed. However, after
30 min incubation of these mutated enzymes at 30°C, the I108R, T156R, N177R, and wild-type kept the
80%, 50%, 20%, and 20% of their original activity, respectively. It should be noted that substitution of
these residues by Arg preserved the specific activity of firefly luciferase.
Conclusion:
Based on these results, it can be concluded that T156R and N177R mutants by compacting
local protein structure, increased the thermostability of luciferase. However, insertion of positively
charged residues in these positions create the new hydrogen bonds that associated with a series of
structural changes and confirmed by intrinsic and extrinsic fluorescence spectroscopy and homology
modeling studies.
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Affiliation(s)
- Farzane Kargar
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
| | - Mojtaba Mortazavi
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
| | - Masoud Torkzadeh-Mahani
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
| | - Safa Lotfi
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
| | - Shahryar Shakeri
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
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20
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Bundela R, Keown J, Watkin S, Pearce FG. Structure of a hyperthermostable dimeric archaeal Rubisco from Hyperthermus butylicus. Acta Crystallogr D Struct Biol 2019; 75:536-544. [DOI: 10.1107/s2059798319006466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 05/07/2019] [Indexed: 11/11/2022] Open
Abstract
The crystal structure of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) from the hyperthermophilic archaeonHyperthermus butylicusis presented at 1.8 Å resolution. Previous structures of archaeal Rubisco have been found to assemble into decamers, and this oligomerization was thought to be required for a highly thermally stable enzyme. In the current study,H. butylicusRubisco is shown to exist as a dimer in solution, yet has a thermal denaturation midpoint of 114°C, suggesting that high thermal stability can be achieved without an increased oligomeric state. This increased thermal stability appears to be due to an increased number of electrostatic interactions within the monomeric subunit. As such,H. butylicusRubisco presents a well characterized system in which to investigate the role of assembly and thermal stability in enzyme function.
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21
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Huijbers MME, Wu JW, Westphal AH, Berkel WJH. Dimerization of Proline Dehydrogenase from
Thermus thermophilus
Is Crucial for Its Thermostability. Biotechnol J 2019; 14:e1800540. [DOI: 10.1002/biot.201800540] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/22/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Mieke M. E. Huijbers
- Laboratory of BiochemistryWageningen University & ResearchStippeneng 4, 6708 WE Wageningen The Netherlands
| | - Jenny W. Wu
- Laboratory of BiochemistryWageningen University & ResearchStippeneng 4, 6708 WE Wageningen The Netherlands
| | - Adrie H. Westphal
- Laboratory of BiochemistryWageningen University & ResearchStippeneng 4, 6708 WE Wageningen The Netherlands
| | - Willem J. H. Berkel
- Laboratory of BiochemistryWageningen University & ResearchStippeneng 4, 6708 WE Wageningen The Netherlands
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22
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Kocaman S, Serpersu EH. The Thermodynamics of Ligand Binding to the Aminoglycoside O-Nucleotidyltransferase(4′) and Variants Yields Clues about Thermophilic Properties. Biochemistry 2019; 58:1579-1586. [DOI: 10.1021/acs.biochem.8b01201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Seda Kocaman
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Engin H. Serpersu
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, Tennessee 37996, United States
- Graduate School of Genome Science and Technology, The University of Tennessee and Oak Ridge National Laboratories, Knoxville, Tennessee 37996, United States
- National Science Foundation, 2415 Eisenhower Avenue, Alexandria, Virginia 22314, United States
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23
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Devi S, Savitri, Raj T, Sharma N, Azmi W. In silicoAnalysis of L-Glutaminase from Extremophiles. CURR PROTEOMICS 2019. [DOI: 10.2174/1570164615666180911110606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:L-glutaminase enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amides. Protein L-glutaminase, which converts amino acid glutamine to a glutamate residue, is useful as antileukemic agent, antiretroviral agent and a new food-processing enzyme.Objective:The sequences representing L-glutaminase from extremophiles were analyzed for different physico-chemical properties and to relate these observed differences to their extremophilic properties, phylogenetic tree construction and the evolutionary relationship among them.Methods:In this work, in silico analysis of amino acid sequences of extremophilic (thermophile, halophile and psychrophiles) proteins has been done. The physiochemical properties of these four groups of proteins for L-glutaminase also differ in number of amino acids, aliphatic index and grand average of hydropathicity (GRAVY).Result:The GRAVY was found to be significantly high in thermophilic (2.29 fold) and psychrophilic bacteria (3.3 fold) as compare to mesophilic bacteria. The amino acid Cys (C) was found to be statistically significant in mesophilic bacteria (approximately or more than 3 fold) as compared to the abundance of this amino acid in extremophilic bacteria.Conclusion:Multiple sequence alignment revealed the domain/motif for glutaminase that consists of Ser-74, Lys-77, Asn-126, Lys-268, and Ser-269, which is highly conserved in all microorganisms.
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Affiliation(s)
- Sarita Devi
- Department of Biotechnology, Himachal Pradesh University, Summer Hill, Shimla, India
| | - Savitri
- Department of Biotechnology, Himachal Pradesh University, Summer Hill, Shimla, India
| | - Tilak Raj
- Sub-Distributed Information Centre, Himachal Pradesh University, Summer Hill, Shimla, India
| | - Nikhil Sharma
- Sub-Distributed Information Centre, Himachal Pradesh University, Summer Hill, Shimla, India
| | - Wamik Azmi
- Department of Biotechnology, Himachal Pradesh University, Summer Hill, Shimla, India
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24
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Kurczab R, Śliwa P, Rataj K, Kafel R, Bojarski AJ. Salt Bridge in Ligand-Protein Complexes-Systematic Theoretical and Statistical Investigations. J Chem Inf Model 2018; 58:2224-2238. [PMID: 30351056 DOI: 10.1021/acs.jcim.8b00266] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Although the salt bridge is the strongest among all known noncovalent molecular interactions, no comprehensive studies have been conducted to date to examine its role and significance in drug design. Thus, a systematic study of the salt bridge in biological systems is reported herein, with a broad analysis of publicly available data from Protein Data Bank, DrugBank, ChEMBL, and GPCRdb. The results revealed the distance and angular preferences as well as privileged molecular motifs of salt bridges in ligand-receptor complexes, which could be used to design the strongest interactions. Moreover, using quantum chemical calculations at the MP2 level, the energetic, directionality, and spatial variabilities of salt bridges were investigated using simple model systems mimicking salt bridges in a biological environment. Additionally, natural orbitals for chemical valence (NOCV) combined with the extended-transition-state (ETS) bond-energy decomposition method (ETS-NOCV) were analyzed and indicated a strong covalent contribution to the salt bridge interaction. The present results could be useful for implementation in rational drug design protocols.
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Affiliation(s)
- Rafał Kurczab
- Department of Medicinal Chemistry, Institute of Pharmacology , Polish Academy of Sciences , Smetna 12 , 31-343 Cracow , Poland
| | - Paweł Śliwa
- Faculty of Chemical Engineering and Technology , Cracow University of Technology , Warszawska 24 , 31-155 Cracow , Poland
| | - Krzysztof Rataj
- Department of Medicinal Chemistry, Institute of Pharmacology , Polish Academy of Sciences , Smetna 12 , 31-343 Cracow , Poland
| | - Rafał Kafel
- Department of Medicinal Chemistry, Institute of Pharmacology , Polish Academy of Sciences , Smetna 12 , 31-343 Cracow , Poland
| | - Andrzej J Bojarski
- Department of Medicinal Chemistry, Institute of Pharmacology , Polish Academy of Sciences , Smetna 12 , 31-343 Cracow , Poland
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25
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Liao ML, Zhang S, Zhang GY, Chu YM, Somero GN, Dong YW. Heat-resistant cytosolic malate dehydrogenases (cMDHs) of thermophilic intertidal snails (genus Echinolittorina): protein underpinnings of tolerance to body temperatures reaching 55°C. ACTA ACUST UNITED AC 2018; 220:2066-2075. [PMID: 28566358 DOI: 10.1242/jeb.156935] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 03/20/2017] [Indexed: 01/07/2023]
Abstract
Snails of the genus Echinolittorina are among the most heat-tolerant animals; they experience average body temperatures near 41-44°C in summer and withstand temperatures up to at least 55°C. Here, we demonstrate that heat stability of function (indexed by the Michaelis-Menten constant of the cofactor NADH, KMNADH) and structure (indexed by rate of denaturation) of cytosolic malate dehydrogenases (cMDHs) of two congeners (E. malaccana and E. radiata) exceeds values previously found for orthologs of this protein from less thermophilic species. The ortholog of E. malaccana is more heat stable than that of E. radiata, in keeping with the congeners' thermal environments. Only two inter-congener differences in amino acid sequence in these 332 residue proteins were identified. In both cases (positions 48 and 114), a glycine in the E. malaccana ortholog is replaced by a serine in the E. radiata protein. To explore the relationship between structure and function and to characterize how amino acid substitutions alter stability of different regions of the enzyme, we used molecular dynamics simulation methods. These computational methods allow determination of thermal effects on fine-scale movements of protein components, for example, by estimating the root mean square deviation in atom position over time and the root mean square fluctuation for individual residues. The minor changes in amino acid sequence favor temperature-adaptive change in flexibility of regions in and around the active sites. Interspecific differences in effects of temperature on fine-scale protein movements are consistent with the differences in thermal effects on binding and rates of heat denaturation.
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Affiliation(s)
- Ming-Ling Liao
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, China.,Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen 361102, China
| | - Shu Zhang
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, China.,Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen 361102, China
| | - Guang-Ya Zhang
- Department of Biotechnology and Engineering, Huaqiao University, Xiamen 361021, China
| | - Yun-Meng Chu
- Department of Biotechnology and Engineering, Huaqiao University, Xiamen 361021, China
| | - George N Somero
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA 93940, USA
| | - Yun-Wei Dong
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, China .,Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen 361102, China
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26
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Wang X, Liu X, Xiao Y, Hao H, Zhang Y, Tang R. Biomineralization State of Viruses and Their Biological Potential. Chemistry 2018; 24:11518-11529. [PMID: 29377301 DOI: 10.1002/chem.201705936] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Indexed: 11/06/2022]
Abstract
In nature, viruses can realize self-mineralization under metal-ion-abundant conditions. Interestingly, the mineralized state is a transition state of the virus when the host is not available. Mammalian viruses that share the similar chemical properties also stand a chance of transformation into a mineralized state. In this review, we focus on the possibility of mammalian viruses to undergo mineralization under a physiological environment and the development of biomineralized-based virus engineering. We will introduce the effect of biomineralization on the physiochemical or biological properties of viruses and we will discuss the relationship between mineral composition and biological potentials. The new biological prospects of mineralized-state viruses, including bypassing biological barriers, protection, and virus-host recognition, will provide new insight for the biosecurity and prevention of viral infection. With respect to vaccines, the mineralized state can modulate the immune recognition, change the immunization route, and elevate the vaccine efficacy. Together, these findings of the mineralized state of the virus may lead to a new understanding of virus biology, application, and prevention.
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Affiliation(s)
- Xiaoyu Wang
- Qiushi Academy for Advanced Studies, Zhejiang University, No.38 Zheda Road, Hangzhou, Zhejiang, 310027, P. R. China
| | - Xueyao Liu
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University, No.38 Zheda Road, Hangzhou, Zhejiang, 310027, P. R. China
| | - Yun Xiao
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University, No.38 Zheda Road, Hangzhou, Zhejiang, 310027, P. R. China
| | - Haibin Hao
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University, No.38 Zheda Road, Hangzhou, Zhejiang, 310027, P. R. China
| | - Ying Zhang
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University, No.38 Zheda Road, Hangzhou, Zhejiang, 310027, P. R. China
| | - Ruikang Tang
- Qiushi Academy for Advanced Studies, Zhejiang University, No.38 Zheda Road, Hangzhou, Zhejiang, 310027, P. R. China.,Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University, No.38 Zheda Road, Hangzhou, Zhejiang, 310027, P. R. China
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27
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Emruzi Z, Aminzadeh S, Karkhane AA, Alikhajeh J, Haghbeen K, Gholami D. Improving the thermostability of Serratia marcescens B4A chitinase via G191V site-directed mutagenesis. Int J Biol Macromol 2018; 116:64-70. [PMID: 29733926 DOI: 10.1016/j.ijbiomac.2018.05.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/26/2018] [Accepted: 05/03/2018] [Indexed: 11/24/2022]
Abstract
Chitinases with high thermostability are important for many industrial and biotechnological applications. This study was conducted to enhance the stability of Serratia marcescens B4A chitinase by site directed mutagenesis of G191 V. Further characterization showed that the thermal stability of the mutant showed marked increase of about 5 and 15 fold at 50 and 60 °C respectively, while the optimum temperature and pH was retained. Kinetic analysis showed decreased Km and Vmax of the mutant in comparison with the wild type chitinase of about 1.3 and 3 fold, respectively. Based on structural prediction, it was speculated that this replacement shortened an important loop concomitant with the extension of adjacent β sheets. Accordingly, a higher thermostability of G191 V up to 90 °C supporting the decreased flexibility of unfolded state was also indicated. Finally, a practical proof of kinetic and thermal stabilization of chitinase was provided through decreased flexibility and entropic stabilization of its surface loops.
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Affiliation(s)
- Zeinab Emruzi
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, (NIGEB), Tehran, Iran
| | - Saeed Aminzadeh
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, (NIGEB), Tehran, Iran.
| | - Ali Asghar Karkhane
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, (NIGEB), Tehran, Iran
| | - Jahan Alikhajeh
- Departments of Physiology and Cellular Biophysics, Columbia University Medical Center, USA
| | - Kamahldin Haghbeen
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, (NIGEB), Tehran, Iran
| | - Dariush Gholami
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, (NIGEB), Tehran, Iran
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28
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Zhou HX, Pang X. Electrostatic Interactions in Protein Structure, Folding, Binding, and Condensation. Chem Rev 2018; 118:1691-1741. [PMID: 29319301 DOI: 10.1021/acs.chemrev.7b00305] [Citation(s) in RCA: 454] [Impact Index Per Article: 75.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Charged and polar groups, through forming ion pairs, hydrogen bonds, and other less specific electrostatic interactions, impart important properties to proteins. Modulation of the charges on the amino acids, e.g., by pH and by phosphorylation and dephosphorylation, have significant effects such as protein denaturation and switch-like response of signal transduction networks. This review aims to present a unifying theme among the various effects of protein charges and polar groups. Simple models will be used to illustrate basic ideas about electrostatic interactions in proteins, and these ideas in turn will be used to elucidate the roles of electrostatic interactions in protein structure, folding, binding, condensation, and related biological functions. In particular, we will examine how charged side chains are spatially distributed in various types of proteins and how electrostatic interactions affect thermodynamic and kinetic properties of proteins. Our hope is to capture both important historical developments and recent experimental and theoretical advances in quantifying electrostatic contributions of proteins.
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Affiliation(s)
- Huan-Xiang Zhou
- Department of Chemistry and Department of Physics, University of Illinois at Chicago , Chicago, Illinois 60607, United States.,Department of Physics and Institute of Molecular Biophysics, Florida State University , Tallahassee, Florida 32306, United States
| | - Xiaodong Pang
- Department of Physics and Institute of Molecular Biophysics, Florida State University , Tallahassee, Florida 32306, United States
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29
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Shah MA, Mishra S, Chaudhuri TK. Marginal stability drives irreversible unfolding of large multi-domain family 3 glycosylhydrolases from thermo-tolerant yeast. Int J Biol Macromol 2017; 108:1322-1330. [PMID: 29141194 DOI: 10.1016/j.ijbiomac.2017.11.041] [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: 08/30/2017] [Revised: 11/01/2017] [Accepted: 11/08/2017] [Indexed: 10/18/2022]
Abstract
Protein folding is an extremely complex and fast, yet perfectly defined process, involving interplay of many intra and inter-molecular forces. In vitro, these molecular interactions are reversible for many proteins e.g., smaller and monomeric, organized into single domains. However, refolding of larger multi-domain/multimeric proteins is much more complicated, proceeds in a hierarchal way and is often irreversible. In a comparative study on two large, multi-domain and multimeric isozymes, β-glucosidase I (BGLI) and β-glucosidase II (BGLII) from Pichia etchellsii, we studied spontaneous and assisted refolding under three denaturing conditions viz. GdnHCl, alkaline pH and heat. During refolding, higher refolding yields were obtained for BGLII in case of pH induced unfolding (13.89%±0.25) than BGLI (6%±0.85) while for GdnHCl induced unfolding, refolding was marginal (BGLI=5%±0.5; BGLII=6%±0.69). Thermal unfolding was irreversible while assisted refolding also showed little structural gain for both proteins. When the apparent free energies of unfolding (ΔGUapp) were calculated from GdnHCl unfolding data, their values were strikingly found to be lower (BGLI ΔGUapp=3.02kcal/mol; BGLII ΔGUapp=2.99kcal/mol) than reported for globular (ΔGU=5-15kcal/mol)/multimeric proteins (ΔGU=23-29kcal/mol) indicating marginal stability results in low refolding.
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Affiliation(s)
- Mohammad Asif Shah
- Department of Biochemical Engineering & Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
| | - Saroj Mishra
- Department of Biochemical Engineering & Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Tapan Kumar Chaudhuri
- Department of Biochemical Engineering & Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India; Ksuma School of Biological Sciences, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
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30
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Goswami S, Das S, Datta S. Understanding the role of residues around the active site tunnel towards generating a glucose-tolerant β-glucosidase from Agrobacterium tumefaciens 5A. Protein Eng Des Sel 2017; 30:523-530. [DOI: 10.1093/protein/gzx039] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 07/10/2017] [Indexed: 12/18/2022] Open
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31
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Jing X, Evangelista Falcon W, Baudry J, Serpersu EH. Thermophilic Enzyme or Mesophilic Enzyme with Enhanced Thermostability: Can We Draw a Line? J Phys Chem B 2017; 121:7086-7094. [DOI: 10.1021/acs.jpcb.7b04519] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Wilfredo Evangelista Falcon
- UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Jerome Baudry
- UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
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32
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Grishin DV, Pokrovskaya MV, Podobed OV, Gladilina JA, Pokrovsky VS, Aleksandrova SS, Sokolov NN. [Prediction of protein thermostability from their primary structure: the current state and development factors]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2017; 63:124-131. [PMID: 28414283 DOI: 10.18097/pbmc20176302124] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The construction of proteins and peptides with desired properties, including resistance to high temperatures, as well as optimization of their amino acid composition, is an important and complex task, which attracts much attention in various branches of the basic sciences, and also in biomedicine and biotechnology. This raises the question: what method is more relevant for the at the pilot stage of research in order to estimate the influence of the planned amino acid substitutions on the thermostability of the resultant protein construct? In this brief review we have classified existing basic practical and theoretical approaches used in studies and predicting the thermal stability of native and recombinant polypeptides. Particular attention has been paid to the predictive potential of statistical methods for studying the thermodynamic parameters of the primary protein structure and prospects of their use.
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Affiliation(s)
- D V Grishin
- Institute of Biomedical Chemistry, Moscow, Russia
| | | | - O V Podobed
- Institute of Biomedical Chemistry, Moscow, Russia
| | | | | | | | - N N Sokolov
- Institute of Biomedical Chemistry, Moscow, Russia
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33
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Chakravorty D, Khan MF, Patra S. Multifactorial level of extremostability of proteins: can they be exploited for protein engineering? Extremophiles 2017; 21:419-444. [PMID: 28283770 DOI: 10.1007/s00792-016-0908-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 12/19/2016] [Indexed: 12/20/2022]
Abstract
Research on extremostable proteins has seen immense growth in the past decade owing to their industrial importance. Basic research of attributes related to extreme-stability requires further exploration. Modern mechanistic approaches to engineer such proteins in vitro will have more impact in industrial biotechnology economy. Developing a priori knowledge about the mechanism behind extreme-stability will nurture better understanding of pathways leading to protein molecular evolution and folding. This review is a vivid compilation about all classes of extremostable proteins and the attributes that lead to myriad of adaptations divulged after an extensive study of 6495 articles belonging to extremostable proteins. Along with detailing on the rationale behind extreme-stability of proteins, emphasis has been put on modern approaches that have been utilized to render proteins extremostable by protein engineering. It was understood that each protein shows different approaches to extreme-stability governed by minute differences in their biophysical properties and the milieu in which they exist. Any general rule has not yet been drawn regarding adaptive mechanisms in extreme environments. This review was further instrumental to understand the drawback of the available 14 stabilizing mutation prediction algorithms. Thus, this review lays the foundation to further explore the biophysical pleiotropy of extreme-stable proteins to deduce a global prediction model for predicting the effect of mutations on protein stability.
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Affiliation(s)
- Debamitra Chakravorty
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Mohd Faheem Khan
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Sanjukta Patra
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
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34
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Poorebrahim M, Sadeghi S, Rahimi H, Karimipoor M, Azadmanesh K, Mazlomi MA, Teimoori-Toolabi L. Rational design of DKK3 structure-based small peptides as antagonists of Wnt signaling pathway and in silico evaluation of their efficiency. PLoS One 2017; 12:e0172217. [PMID: 28234935 PMCID: PMC5325476 DOI: 10.1371/journal.pone.0172217] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Accepted: 02/01/2017] [Indexed: 12/31/2022] Open
Abstract
Dysregulated Wnt signaling pathway is highly associated with the pathogenesis of several human cancers. Dickkopf proteins (DKKs) are thought to inhibit Wnt signaling pathway through binding to lipoprotein receptor-related protein (LRP) 5/6. In this study, based on the 3-dimensional (3D) structure of DKK3 Cys-rich domain 2 (CRD2), we have designed and developed several peptide inhibitors of Wnt signaling pathway. Modeller 9.15 package was used to predict 3D structure of CRD2 based on the Homology modeling (HM) protocol. After refinement and minimization with GalaxyRefine and NOMAD-REF servers, the quality of selected models was evaluated utilizing VADAR, SAVES and ProSA servers. Molecular docking studies as well as literature-based information revealed two distinct boxes located at CRD2 which are actively involved in the DKK3-LRP5/6 interaction. A peptide library was constructed conducting the backrub sequence tolerance scanning protocol in Rosetta3.5 according to the DKK3-LRP5/6 binding sites. Seven tolerated peptides were chosen and their binding affinity and stability were improved by some logical amino acid substitutions. Molecular dynamics (MD) simulations of peptide-LRP5/6 complexes were carried out using GROMACS package. After evaluation of binding free energies, stability, electrostatic potential and some physicochemical properties utilizing computational approaches, three peptides (PEP-I1, PEP-I3 and PEP-II2) demonstrated desirable features. However, all seven improved peptides could sufficiently block the Wnt-binding site of LRP6 in silico. In conclusion, we have designed and improved several small peptides based on the LRP6-binding site of CRD2 of DKK3. These peptides are highly capable of binding to LRP6 in silico, and may prevent the formation of active Wnt-LRP6-Fz complex.
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Affiliation(s)
- Mansour Poorebrahim
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Molecular Medicine Department, Pasteur Institute of Iran, Tehran, Iran
| | - Solmaz Sadeghi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Molecular Medicine Department, Pasteur Institute of Iran, Tehran, Iran
| | - Hamzeh Rahimi
- Molecular Medicine Department, Pasteur Institute of Iran, Tehran, Iran
| | | | | | - Mohammad Ali Mazlomi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Ladan Teimoori-Toolabi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Molecular Medicine Department, Pasteur Institute of Iran, Tehran, Iran
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35
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Makhatadze GI. Linking computation and experiments to study the role of charge-charge interactions in protein folding and stability. Phys Biol 2017; 14:013002. [PMID: 28169222 DOI: 10.1088/1478-3975/14/1/013002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Over the past two decades there has been an increase in appreciation for the role of surface charge-charge interactions in protein folding and stability. The perception shifted from the belief that charge-charge interactions are not important for protein folding and stability to the near quantitative understanding of how these interactions shape the folding energy landscape. This led to the ability of computational approaches to rationally redesign surface charge-charge interactions to modulate thermodynamic properties of proteins. Here we summarize our progress in understanding the role of charge-charge interactions for protein stability using examples drawn from my own laboratory and touch upon unanswered questions.
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Affiliation(s)
- George I Makhatadze
- Center for Biotechnology and Interdisciplinary Studies, and Department of Biological Sciences, Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 USA
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36
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Surface charge modification increases firefly luciferase rigidity without alteration in bioluminescence spectra. Enzyme Microb Technol 2017; 96:47-59. [DOI: 10.1016/j.enzmictec.2016.09.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 12/15/2022]
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37
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Batra J, Tjong H, Zhou HX. Electrostatic effects on the folding stability of FKBP12. Protein Eng Des Sel 2016; 29:301-308. [PMID: 27381026 PMCID: PMC4955870 DOI: 10.1093/protein/gzw014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 03/28/2016] [Accepted: 04/15/2016] [Indexed: 01/17/2023] Open
Abstract
The roles of electrostatic interactions in protein folding stability have been a matter of debate, largely due to the complexity in the theoretical treatment of these interactions. We have developed computational methods for calculating electrostatic effects on protein folding stability. To rigorously test and further refine these methods, here we carried out experimental studies into electrostatic effects on the folding stability of the human 12-kD FK506 binding protein (FKBP12). This protein has a close homologue, FKBP12.6, with amino acid substitutions in only 18 of their 107 residues. Of the 18 substitutions, 8 involve charged residues. Upon mutating FKBP12 residues at these 8 positions individually into the counterparts in FKBP12.6, the unfolding free energy (ΔGu) of FKBP12 changed by -0.3 to 0.7 kcal/mol. Accumulating stabilizing substitutions resulted in a mutant with a 0.9 kcal/mol increase in stability. Additional charge mutations were grafted from a thermophilic homologue, MtFKBP17, which aligns to FKBP12 with 31% sequence identity over 89 positions. Eleven such charge mutations were studied, with ΔΔGu varying from -2.9 to 0.1 kcal/mol. The predicted electrostatic effects by our computational methods with refinements herein had a root-mean-square deviation of 0.9 kcal/mol from the experimental ΔΔGu values on 16 single mutations of FKBP12. The difference in ΔΔGu between mutations grafted from FKBP12.6 and those from MtFKBP17 suggests that more distant homologues are less able to provide guidance for enhancing folding stability.
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Affiliation(s)
- Jyotica Batra
- Department of Physics and Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
- Present address: Department of Chemistry and Physics, Bellarmine University, 2001 Newburg Road, Louisville, KY40205, USA
| | - Harianto Tjong
- Department of Physics and Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
- Present address: Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Huan-Xiang Zhou
- Department of Physics and Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
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38
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A single mutation Gln142Lys doubles the catalytic activity of VPR, a cold adapted subtilisin-like serine proteinase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:1436-43. [PMID: 27456266 DOI: 10.1016/j.bbapap.2016.07.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 07/11/2016] [Accepted: 07/15/2016] [Indexed: 11/20/2022]
Abstract
Structural comparisons of the cold adapted subtilase VPR and its thermophilic homologue, aqualysin I (AQUI) indicated the presence of additional salt bridges in the latter. Few of those appear to contribute significantly to thermal stability of AQUI. This includes a putative salt bridge between residues Lys142 and Glu172 as its deletion did not have any significant effect on its stability or activity (Jónsdóttir et al. (2014)). Insertion of this putative salt bridge into the structure of VPR, in a double mutant (VPRΔC_Q142K/S172E), however was detrimental to the stability of the enzyme. Incorporation of either the Q142K or S172E mutations into VPR, were found to significantly affect the catalytic properties of the enzyme. The single mutation Q142K was highly effective, as it increased the kcat and kcat/Km more than twofold. When the Q142K mutation was inserted into a thermostabilized, but a low activity mutant of VPR (VPRΔC_N3P/I5P), the activity increased about tenfold in terms of kcat and kcat/Km, while retaining the stability of the mutant. Molecular dynamics simulations of the single mutants were carried out to provide structural rationale for these experimental observations. Based on root mean square fluctuation (RMSF) profiles, the two mutants were more flexible in certain regions of the structure and the Q142K mutant had the highest overall flexibility of the three enzymes. The results suggest that weakening of specific H-bonds resulting from the mutations may be propagated over some distance giving rise to higher flexibility in the active site regions of the enzyme, causing higher catalytic activity in the mutants.
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39
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Højgaard C, Kofoed C, Espersen R, Johansson KE, Villa M, Willemoës M, Lindorff-Larsen K, Teilum K, Winther JR. A Soluble, Folded Protein without Charged Amino Acid Residues. Biochemistry 2016; 55:3949-56. [PMID: 27307139 DOI: 10.1021/acs.biochem.6b00269] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Charges are considered an integral part of protein structure and function, enhancing solubility and providing specificity in molecular interactions. We wished to investigate whether charged amino acids are indeed required for protein biogenesis and whether a protein completely free of titratable side chains can maintain solubility, stability, and function. As a model, we used a cellulose-binding domain from Cellulomonas fimi, which, among proteins of more than 100 amino acids, presently is the least charged in the Protein Data Bank, with a total of only four titratable residues. We find that the protein shows a surprising resilience toward extremes of pH, demonstrating stability and function (cellulose binding) in the pH range from 2 to 11. To ask whether the four charged residues present were required for these properties of this protein, we altered them to nontitratable ones. Remarkably, this chargeless protein is produced reasonably well in Escherichia coli, retains its stable three-dimensional structure, and is still capable of strong cellulose binding. To further deprive this protein of charges, we removed the N-terminal charge by acetylation and studied the protein at pH 2, where the C-terminus is effectively protonated. Under these conditions, the protein retains its function and proved to be both soluble and have a reversible folding-unfolding transition. To the best of our knowledge, this is the first time a soluble, functional protein with no titratable side chains has been produced.
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Affiliation(s)
- Casper Højgaard
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Christian Kofoed
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Roall Espersen
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Kristoffer Enøe Johansson
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Mara Villa
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Martin Willemoës
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Kresten Lindorff-Larsen
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Kaare Teilum
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
| | - Jakob R Winther
- Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen , DK-2200 Copenhagen N, Denmark
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40
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Sobhani-Damavandifar Z, Hosseinkhani S, Sajedi RH. Proposed ionic bond between Arg300 and Glu270 and Glu271 are not involved in inactivation of a mutant firefly luciferase (LRR). Enzyme Microb Technol 2016; 86:17-24. [PMID: 26992788 DOI: 10.1016/j.enzmictec.2016.01.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/18/2016] [Accepted: 01/21/2016] [Indexed: 10/22/2022]
Abstract
The weakness of firefly luciferase is its rapid inactivation. Many studies have been done to develop thermostable luciferases. One of these modifications was LRR mutant in which the Leu300 was substituted with Arg in the E(354)RR(356)Lampyris turkestanicus luciferase as template. LRR was more thermostable than the wild type but with only 0.02% activity. In this study, site-directed mutagenesis was used to change the proposed ionic bond between the Arg and two neighboring residues (Glu270 and Glu271), to understand if the induced interactions were responsible for inactivation in LRR. Our results showed that substitution of Glu270 and 271 with Ala removed the interactions but the activity of enzyme did not return. The E270A mutant was more active than LRR but the E271A and E270A/E271A mutants were inactive. Fluorescence and CD measurements showed that these mutations were accompanied by conformational changes. Extrinsic fluorescence measurement and obtained quenching data by KI and acrylamide also confirmed that the mutants were less compact than the LRR enzyme. In conclusion, in LRR, the interactions between Arg300 and Glu270 and Glu271 were not responsible for the enzyme inactivation and it is proposed that the enzyme inactivation is due to conformational changes of LRR mutant of firefly luciferase.
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Affiliation(s)
| | - Saman Hosseinkhani
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Reza H Sajedi
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
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41
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Hinzman MW, Essex ME, Park C. Salt bridge as a gatekeeper against partial unfolding. Protein Sci 2016; 25:999-1009. [PMID: 26916981 DOI: 10.1002/pro.2908] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 02/23/2016] [Accepted: 02/23/2016] [Indexed: 11/06/2022]
Abstract
Salt bridges are frequently observed in protein structures. Because the energetic contribution of salt bridges is strongly dependent on the environmental context, salt bridges are believed to contribute to the structural specificity rather than the stability. To test the role of salt bridges in enhancing structural specificity, we investigated the contribution of a salt bridge to the energetics of native-state partial unfolding in a cysteine-free version of Escherichia coli ribonuclease H (RNase H*). Thermolysin cleaves a protruding loop of RNase H(*) through transient partial unfolding under native conditions. Lys86 and Asp108 in RNase H(*) form a partially buried salt bridge that tethers the protruding loop. Investigation of the global stability of K86Q/D108N RNase H(*) showed that the salt bridge does not significantly contribute to the global stability. However, K86Q/D108N RNase H(*) is greatly more susceptible to proteolysis by thermolysin than wild-type RNase H(*) is. The free energy for partial unfolding determined by native-state proteolysis indicates that the salt bridge significantly increases the energy for partial unfolding by destabilizing the partially unfolded form. Double mutant cycles with single and double mutations of the salt bridge suggest that the partially unfolded form is destabilized due to a significant decrease in the interaction energy between Lys86 and Asp108 upon partial unfolding. This study demonstrates that, even in the case that a salt bridge does not contribute to the global stability, the salt bridge may function as a gatekeeper against partial unfolding that disturbs the optimal geometry of the salt bridge.
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Affiliation(s)
- Mark W Hinzman
- Department of Medicinal Chemistry and Molecular Pharmacology, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, 47907
| | - Morgan E Essex
- Department of Medicinal Chemistry and Molecular Pharmacology, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, 47907
| | - Chiwook Park
- Department of Medicinal Chemistry and Molecular Pharmacology, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, 47907
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42
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Sammond DW, Kastelowitz N, Himmel ME, Yin H, Crowley MF, Bomble YJ. Comparing Residue Clusters from Thermophilic and Mesophilic Enzymes Reveals Adaptive Mechanisms. PLoS One 2016; 11:e0145848. [PMID: 26741367 PMCID: PMC4704809 DOI: 10.1371/journal.pone.0145848] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 12/09/2015] [Indexed: 11/18/2022] Open
Abstract
Understanding how proteins adapt to function at high temperatures is important for deciphering the energetics that dictate protein stability and folding. While multiple principles important for thermostability have been identified, we lack a unified understanding of how internal protein structural and chemical environment determine qualitative or quantitative impact of evolutionary mutations. In this work we compare equivalent clusters of spatially neighboring residues between paired thermophilic and mesophilic homologues to evaluate adaptations under the selective pressure of high temperature. We find the residue clusters in thermophilic enzymes generally display improved atomic packing compared to mesophilic enzymes, in agreement with previous research. Unlike residue clusters from mesophilic enzymes, however, thermophilic residue clusters do not have significant cavities. In addition, anchor residues found in many clusters are highly conserved with respect to atomic packing between both thermophilic and mesophilic enzymes. Thus the improvements in atomic packing observed in thermophilic homologues are not derived from these anchor residues but from neighboring positions, which may serve to expand optimized protein core regions.
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Affiliation(s)
- Deanne W Sammond
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, 80401, United States of America
| | - Noah Kastelowitz
- Department of Chemistry & Biochemistry and the BioFrontiers Institute, University of Colorado, Boulder, Colorado, 80309, United States of America
| | - Michael E Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, 80401, United States of America
| | - Hang Yin
- Department of Chemistry & Biochemistry and the BioFrontiers Institute, University of Colorado, Boulder, Colorado, 80309, United States of America
| | - Michael F Crowley
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, 80401, United States of America
| | - Yannick J Bomble
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, 80401, United States of America
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43
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Park SH, Kim HS, Park MS, Moon S, Song MK, Park HS, Hahn H, Kim SJ, Bae E, Kim HJ, Han BW. Structure and Stability of the Dimeric Triosephosphate Isomerase from the Thermophilic Archaeon Thermoplasma acidophilum. PLoS One 2015; 10:e0145331. [PMID: 26709515 PMCID: PMC4692482 DOI: 10.1371/journal.pone.0145331] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 12/02/2015] [Indexed: 01/03/2023] Open
Abstract
Thermoplasma acidophilum is a thermophilic archaeon that uses both non-phosphorylative Entner-Doudoroff (ED) pathway and Embden-Meyerhof-Parnas (EMP) pathway for glucose degradation. While triosephosphate isomerase (TPI), a well-known glycolytic enzyme, is not involved in the ED pathway in T. acidophilum, it has been considered to play an important role in the EMP pathway. Here, we report crystal structures of apo- and glycerol-3-phosphate-bound TPI from T. acidophilum (TaTPI). TaTPI adopts the canonical TIM-barrel fold with eight α-helices and parallel eight β-strands. Although TaTPI shares ~30% sequence identity to other TPIs from thermophilic species that adopt tetrameric conformation for enzymatic activity in their harsh physiological environments, TaTPI exists as a dimer in solution. We confirmed the dimeric conformation of TaTPI by analytical ultracentrifugation and size-exclusion chromatography. Helix 5 as well as helix 4 of thermostable tetrameric TPIs have been known to play crucial roles in oligomerization, forming a hydrophobic interface. However, TaTPI contains unique charged-amino acid residues in the helix 5 and adopts dimer conformation. TaTPI exhibits the apparent Td value of 74.6°C and maintains its overall structure with some changes in the secondary structure contents at extremely acidic conditions (pH 1–2). Based on our structural and biophysical analyses of TaTPI, more compact structure of the protomer with reduced length of loops and certain patches on the surface could account for the robust nature of Thermoplasma acidophilum TPI.
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Affiliation(s)
- Sang Ho Park
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Hyoun Sook Kim
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Mi Seul Park
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Sojin Moon
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Korea
| | - Mi Kyung Song
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Han Su Park
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Hyunggu Hahn
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Soon-Jong Kim
- Department of Chemistry, Mokpo National University, Chonnam, Korea
| | - Euiyoung Bae
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Korea
| | - Hyun-Jung Kim
- College of Pharmacy, Chung-Ang University, Seoul, Korea
| | - Byung Woo Han
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Korea
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Bagarolo ML, Porcelli M, Martino E, Feller G, Cacciapuoti G. Multiple disulfide bridges modulate conformational stability and flexibility in hyperthermophilic archaeal purine nucleoside phosphorylase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:1458-65. [DOI: 10.1016/j.bbapap.2015.06.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 05/27/2015] [Accepted: 06/23/2015] [Indexed: 11/25/2022]
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45
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Veesler D, Kearney BM, Johnson JE. Integration of X-ray crystallography and electron cryo-microscopy in the analysis of virus structure and function. CRYSTALLOGR REV 2015. [DOI: 10.1080/0889311x.2015.1038530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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46
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Karshikoff A, Nilsson L, Ladenstein R. Rigidity versus flexibility: the dilemma of understanding protein thermal stability. FEBS J 2015; 282:3899-917. [PMID: 26074325 DOI: 10.1111/febs.13343] [Citation(s) in RCA: 176] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 05/17/2015] [Accepted: 06/09/2015] [Indexed: 01/19/2023]
Abstract
The role of fluctuations in protein thermostability has recently received considerable attention. In the current literature a dualistic picture can be found: thermostability seems to be associated with enhanced rigidity of the protein scaffold in parallel with the reduction of flexible parts of the structure. In contradiction to such arguments it has been shown by experimental studies and computer simulation that thermal tolerance of a protein is not necessarily correlated with the suppression of internal fluctuations and mobility. Both concepts, rigidity and flexibility, are derived from mechanical engineering and represent temporally insensitive features describing static properties, neglecting that relative motion at certain time scales is possible in structurally stable regions of a protein. This suggests that a strict separation of rigid and flexible parts of a protein molecule does not describe the reality correctly. In this work the concepts of mobility/flexibility versus rigidity will be critically reconsidered by taking into account molecular dynamics calculations of heat capacity and conformational entropy, salt bridge networks, electrostatic interactions in folded and unfolded states, and the emerging picture of protein thermostability in view of recently developed network theories. Last, but not least, the influence of high temperature on the active site and activity of enzymes will be considered.
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Affiliation(s)
- Andrey Karshikoff
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Lennart Nilsson
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Rudolf Ladenstein
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
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47
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Kalimeri M, Derreumaux P, Sterpone F. Are coarse-grained models apt to detect protein thermal stability? The case of OPEP force field. JOURNAL OF NON-CRYSTALLINE SOLIDS 2015; 407:494-501. [PMID: 28100926 PMCID: PMC5238951 DOI: 10.1016/j.jnoncrysol.2014.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We present the first investigation of the kinetic and thermodynamic stability of two homologous thermophilic and mesophilic proteins based on the coarse-grained model OPEP. The object of our investigation is a pair of G-domains of relatively large size, 200 amino acids each, with an experimental stability gap of about 40 K. The OPEP force field is able to maintain stable the fold of these relatively large proteins within the hundrend-nanosecond time scale without including external constraints. This makes possible to characterize the conformational landscape of the folded protein as well as to explore the unfolding. In agreement with all-atom simulations used as a reference, we show that the conformational landscape of the thermophilic protein is characterized by a larger number of substates with slower dynamics on the network of states and more resilient to temperature increase. Moreover, we verify the stability gap between the two proteins using replica-exchange simulations and estimate a difference between the melting temperatures of about 23 K, in fair agreement with experiment. The detailed investigation of the unfolding thermodynamics, allows to gain insight into the mechanism underlying the enhanced stability of the thermophile relating it to a smaller heat capacity of unfolding.
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Affiliation(s)
- Maria Kalimeri
- Laboratoire de Biochimie Théorique, IBPC, CNRS, UPR9080, Univ. Paris Diderot, Sorbonne Paris Cité, France
| | - Philippe Derreumaux
- Laboratoire de Biochimie Théorique, IBPC, CNRS, UPR9080, Univ. Paris Diderot, Sorbonne Paris Cité, France
- Institut Universitaire de France, 103 Boulevard Saint-Michel, 75005, Paris, France
| | - Fabio Sterpone
- Laboratoire de Biochimie Théorique, IBPC, CNRS, UPR9080, Univ. Paris Diderot, Sorbonne Paris Cité, France
- Corresponding author.
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48
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Vorontsova MA, Maes D, Vekilov PG. Recent advances in the understanding of two-step nucleation of protein crystals. Faraday Discuss 2015; 179:27-40. [DOI: 10.1039/c4fd00217b] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The two-step mechanism of nucleation of crystals in solutions posits that the formation of crystal nuclei occurs within structures of extended lifetimes, in which the nucleating solute is at high concentration. The validity of this mechanism has been demonstrated for proteins, small-molecule organic and inorganic materials, colloids, and polymers. Due to large molecule sizes, proteins are an ideal system to study the details of this nucleation pathway, in particular the formation mechanisms of the nucleation precursors and the associated physico-chemical rules. The precursors of protein crystal nuclei are protein-rich clusters of sizes ∼100 nm that contain 10 000–100 000 molecules and occupy less than 10−3of the total solution volume. Here we demonstrate, using oblique illumination microscopy, the liquid nature of the clusters of the protein lysozyme and reveal their inhomogeneous structure. We test a hypothesis put forth by theory that clusters primarily consist of transient protein oligomers. For this, we explore how varying the strength of the Coulomb interaction affects the cluster characteristics. We find that the cluster’s size is insensitive to variations of pH and ionic strength. In contrast, the addition of urea, a chaotropic agent that leads to protein unfolding, strongly decreases the cluster size. Shear stress, a known protein denaturant, induced by bubbling of the solutions with an inert gas, elicits a similar response. These observations support partial protein unfolding, followed by dimerization, as the mechanism of cluster formation. The amide hydrogen–deuterium exchange, monitored by nuclear magnetic resonance, highlights that lysozyme conformational flexibility is a condition for the formation of the protein-rich clusters and facilitates the nucleation of protein crystals.
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Affiliation(s)
- Maria A. Vorontsova
- Department of Chemical and Biomolecular Engineering
- University of Houston
- Houston
- USA
| | - Dominique Maes
- Structural Biology Brussels
- Vrije Universiteit Brussel
- B-1050 Brussel
- Belgium
| | - Peter G. Vekilov
- Department of Chemical and Biomolecular Engineering
- University of Houston
- Houston
- USA
- Department of Chemistry
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49
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Jónsdóttir LB, Ellertsson BÖ, Invernizzi G, Magnúsdóttir M, Thorbjarnardóttir SH, Papaleo E, Kristjánsson MM. The role of salt bridges on the temperature adaptation of aqualysin I, a thermostable subtilisin-like proteinase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:2174-81. [DOI: 10.1016/j.bbapap.2014.08.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/05/2014] [Accepted: 08/20/2014] [Indexed: 11/30/2022]
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50
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Kalimeri M, Girard E, Madern D, Sterpone F. Interface matters: the stiffness route to stability of a thermophilic tetrameric malate dehydrogenase. PLoS One 2014; 9:e113895. [PMID: 25437494 PMCID: PMC4250060 DOI: 10.1371/journal.pone.0113895] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 11/01/2014] [Indexed: 11/19/2022] Open
Abstract
In this work we investigate by computational means the behavior of two orthologous bacterial proteins, a mesophilic and a thermophilic tetrameric malate dehydrogenase (MalDH), at different temperatures. Namely, we quantify how protein mechanical rigidity at different length- and time-scales correlates to protein thermophilicity as commonly believed. In particular by using a clustering analysis strategy to explore the conformational space of the folded proteins, we show that at ambient conditions and at the molecular length-scale the thermophilic variant is indeed more rigid that the mesophilic one. This rigidification is the result of more efficient inter-domain interactions, the strength of which is further quantified via ad hoc free energy calculations. When considered isolated, the thermophilic domain is indeed more flexible than the respective mesophilic one. Upon oligomerization, the induced stiffening of the thermophilic protein propagates from the interface to the active site where the loop, controlling the access to the catalytic pocket, anchors down via an extended network of ion-pairs. On the contrary in the mesophilic tetramer the loop is highly mobile. Simulations at high temperature, could not re-activate the mobility of the loop in the thermophile. This finding opens questions on the similarities of the binding processes for these two homologues at their optimal working temperature and suggests for the thermophilic variant a possible cooperative role of cofactor/substrate.
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Affiliation(s)
- Maria Kalimeri
- Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Centre National de la Recherche Scientifique, UPR9080, Univ. Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Eric Girard
- Univ. Grenoble Alpes, Institut de Biologie Structurale, Grenoble, France
- Centre National de la Recherche Scientifique, Institut de Biologie Structurale, Grenoble, France
- Commissariat à l'Energie Atomique et aux énergies alternatives, Institut de Biologie Structurale, Grenoble, France
| | - Dominique Madern
- Univ. Grenoble Alpes, Institut de Biologie Structurale, Grenoble, France
- Centre National de la Recherche Scientifique, Institut de Biologie Structurale, Grenoble, France
- Commissariat à l'Energie Atomique et aux énergies alternatives, Institut de Biologie Structurale, Grenoble, France
- * E-mail: (FS); (DM)
| | - Fabio Sterpone
- Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Centre National de la Recherche Scientifique, UPR9080, Univ. Paris Diderot, Sorbonne Paris Cité, Paris, France
- * E-mail: (FS); (DM)
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