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Wan H, Zhang Y, Huang S. Prediction of thermophilic protein using 2-D general series correlation pseudo amino acid features. Methods 2023; 218:141-148. [PMID: 37604248 DOI: 10.1016/j.ymeth.2023.08.012] [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: 05/03/2023] [Revised: 07/08/2023] [Accepted: 08/18/2023] [Indexed: 08/23/2023] Open
Abstract
The demand for thermophilic protein has been increasing in protein engineering recently. Many machine-learning methods for identifying thermophilic proteins have emerged during this period. However, most machine learning-based thermophilic protein identification studies have only focused on accuracy. The relationship between the features' meaning and the proteins' physicochemical properties has yet to be studied in depth. In this article, we focused on the relationship between the features and the thermal stability of thermophilic proteins. This method used 2-D general series correlation pseudo amino acid (SC-PseAAC-General) features and realized accuracy of 82.76% using the J48 classifier. In addition, this research found the presence of higher frequencies of glutamic acid in thermophilic proteins, which help thermophilic proteins maintain their thermal stability by forming hydrogen bonds and salt bridges that prevent denaturation at high temperatures.
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Affiliation(s)
- Hao Wan
- College of Life Science, Qingdao University, Qingdao 266071, China.
| | - Yanan Zhang
- College of Life Science, Qingdao University, Qingdao 266071, China
| | - Shibo Huang
- Beidahuang Industry Group General Hospital, Harbin 150001, China
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2
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A Statistical Analysis of the Sequence and Structure of Thermophilic and Non-Thermophilic Proteins. Int J Mol Sci 2022; 23:ijms231710116. [PMID: 36077513 PMCID: PMC9456548 DOI: 10.3390/ijms231710116] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/29/2022] [Accepted: 08/31/2022] [Indexed: 11/17/2022] Open
Abstract
Thermophilic proteins have various practical applications in theoretical research and in industry. In recent years, the demand for thermophilic proteins on an industrial scale has been increasing; therefore, the engineering of thermophilic proteins has become a hot direction in the field of protein engineering. However, the exact mechanism of thermostability of proteins is not yet known, for engineering thermophilic proteins knowing the basis of thermostability is necessary. In order to understand the basis of the thermostability in proteins, we have made a statistical analysis of the sequences, secondary structures, hydrogen bonds, salt bridges, DHA (Donor-Hydrogen-Accepter) angles, and bond lengths of ten pairs of thermophilic proteins and their non-thermophilic orthologous. Our findings suggest that polar amino acids contribute to thermostability in proteins by forming hydrogen bonds and salt bridges which provide resistance against protein denaturation. Short bond length and a wider DHA angle provide greater bond stability in thermophilic proteins. Moreover, the increased frequency of aromatic amino acids in thermophilic proteins contributes to thermal stability by forming more aromatic interactions. Additionally, the coil, helix, and loop in the secondary structure also contribute to thermostability.
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3
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PROTEIN l-ISOASPARTYL METHYLTRANSFERASE (PIMT) in plants: regulations and functions. Biochem J 2020; 477:4453-4471. [PMID: 33245750 DOI: 10.1042/bcj20200794] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 02/06/2023]
Abstract
Proteins are essential molecules that carry out key functions in a cell. However, as a result of aging or stressful environments, the protein undergoes a range of spontaneous covalent modifications, including the formation of abnormal l-isoaspartyl residues from aspartyl or asparaginyl residues, which can disrupt the protein's inherent structure and function. PROTEIN l-ISOASPARTYL METHYLTRANSFERASE (PIMT: EC 2.1.1.77), an evolutionarily conserved ancient protein repairing enzyme (PRE), converts such abnormal l-isoaspartyl residues to normal l-aspartyl residues and re-establishes the protein's native structure and function. Although originally discovered in animals as a PRE, PIMT emerged as a key PRE in plants, particularly in seeds, in which PIMT plays a predominant role in preserving seed vigor and viability for prolonged periods of time. Interestingly, higher plants encode a second PIMT (PIMT2) protein which possesses a unique N-terminal extension, and exhibits several distinct features and far more complexity than non-plant PIMTs. Recent studies indicate that the role of PIMT is not restricted to preserving seed vigor and longevity but is also implicated in enhancing the growth and survivability of plants under stressful environments. Furthermore, expression studies indicate the tantalizing possibility that PIMT is involved in various physiological processes apart from its role in seed vigor, longevity and plant's survivability under abiotic stress. This review article particularly describes new insights and emerging interest in all facets of this enzyme in plants along with a concise comparative overview on isoAsp formation, and the role and regulation of PIMTs across evolutionary diverse species. Additionally, recent methods and their challenges in identifying isoaspartyl containing proteins (PIMT substrates) are highlighted.
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4
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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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5
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Arabidopsis Heat Stress-Induced Proteins Are Enriched in Electrostatically Charged Amino Acids and Intrinsically Disordered Regions. Int J Mol Sci 2018; 19:ijms19082276. [PMID: 30081447 PMCID: PMC6121531 DOI: 10.3390/ijms19082276] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 07/24/2018] [Accepted: 07/31/2018] [Indexed: 01/06/2023] Open
Abstract
Comparison of the proteins of thermophilic, mesophilic, and psychrophilic prokaryotes has revealed several features characteristic to proteins adapted to high temperatures, which increase their thermostability. These characteristics include a profusion of disulfide bonds, salt bridges, hydrogen bonds, and hydrophobic interactions, and a depletion in intrinsically disordered regions. It is unclear, however, whether such differences can also be observed in eukaryotic proteins or when comparing proteins that are adapted to temperatures that are more subtly different. When an organism is exposed to high temperatures, a subset of its proteins is overexpressed (heat-induced proteins), whereas others are either repressed (heat-repressed proteins) or remain unaffected. Here, we determine the expression levels of all genes in the eukaryotic model system Arabidopsis thaliana at 22 and 37 °C, and compare both the amino acid compositions and levels of intrinsic disorder of heat-induced and heat-repressed proteins. We show that, compared to heat-repressed proteins, heat-induced proteins are enriched in electrostatically charged amino acids and depleted in polar amino acids, mirroring thermophile proteins. However, in contrast with thermophile proteins, heat-induced proteins are enriched in intrinsically disordered regions, and depleted in hydrophobic amino acids. Our results indicate that temperature adaptation at the level of amino acid composition and intrinsic disorder can be observed not only in proteins of thermophilic organisms, but also in eukaryotic heat-induced proteins; the underlying adaptation pathways, however, are similar but not the same.
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Watson MD, Monroe J, Raleigh DP. Size-Dependent Relationships between Protein Stability and Thermal Unfolding Temperature Have Important Implications for Analysis of Protein Energetics and High-Throughput Assays of Protein–Ligand Interactions. J Phys Chem B 2017; 122:5278-5285. [DOI: 10.1021/acs.jpcb.7b05684] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Daniel P. Raleigh
- Research Department of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, United Kingdom
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7
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Abstract
Using structure and sequence based analysis we can engineer proteins to increase their thermal stability.
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Affiliation(s)
- H. Pezeshgi Modarres
- Molecular Cell Biomechanics Laboratory
- Departments of Bioengineering and Mechanical Engineering
- University of California Berkeley
- Berkeley
- USA
| | - M. R. Mofrad
- Molecular Cell Biomechanics Laboratory
- Departments of Bioengineering and Mechanical Engineering
- University of California Berkeley
- Berkeley
- USA
| | - A. Sanati-Nezhad
- BioMEMS and Bioinspired Microfluidic Laboratory
- Department of Mechanical and Manufacturing Engineering
- University of Calgary
- Calgary
- Canada
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8
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Kumwenda B, Litthauer D, Bishop OT, Reva O. Analysis of protein thermostability enhancing factors in industrially important thermus bacteria species. Evol Bioinform Online 2013; 9:327-42. [PMID: 24023508 PMCID: PMC3762613 DOI: 10.4137/ebo.s12539] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Elucidation of evolutionary factors that enhance protein thermostability is a critical problem and was the focus of this work on Thermus species. Pairs of orthologous sequences of T. scotoductus SA-01 and T. thermophilus HB27, with the largest negative minimum folding energy (MFE) as predicted by the UNAFold algorithm, were statistically analyzed. Favored substitutions of amino acids residues and their properties were determined. Substitutions were analyzed in modeled protein structures to determine their locations and contribution to energy differences using PyMOL and FoldX programs respectively. Dominant trends in amino acid substitutions consistent with differences in thermostability between orthologous sequences were observed. T. thermophilus thermophilic proteins showed an increase in non-polar, tiny, and charged amino acids. An abundance of alanine substituted by serine and threonine, as well as arginine substituted by glutamine and lysine was observed in T. thermophilus HB27. Structural comparison showed that stabilizing mutations occurred on surfaces and loops in protein structures.
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Affiliation(s)
- Benjamin Kumwenda
- Bioinformatics and Computational Biology Unit, Department of Biochemistry, University of Pretoria, South Africa
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9
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Jha SK, Deepalakshmi PD, Udgaonkar JB. Characterization of deamidation of barstar using electrospray ionization quadrupole time-of-flight mass spectrometry, which stabilizes an equilibrium unfolding intermediate. Protein Sci 2012; 21:633-46. [PMID: 22431291 DOI: 10.1002/pro.2047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 02/01/2012] [Accepted: 02/13/2012] [Indexed: 11/09/2022]
Abstract
Deamidation of asparaginyl residues is a common posttranslational modification in proteins and has been studied extensively because of its important biological effects, such as those on enzymatic activity, protein folding, and proteolytic degradation. However, characterization of the sites of deamidation of a protein has been a difficult analytical problem. In this study, mass spectrometry has been used as an analytical tool to characterize the deamidation of barstar, an RNAse inhibitor. Upon incubation of the protein at alkaline pH for 5 h, intact mass analysis of barstar, using electrospray ionization quadrupole time-of-flight mass spectrometry (ESI QToF MS), indicated an increase in the mass of +2 Da, suggesting possible deamidation of the protein. The sites of deamidation have been identified using the conventional bottom-up approach using a capillary liquid chromatography connected on line to an ESI QToF mass spectrometer and top down approach by direct infusion of the intact protein and fragmenting inside MS. These chemical modifications are shown to lead to stabilization of an unfolding intermediate, which can be observed in equilibrium unfolding studies.
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Affiliation(s)
- Santosh Kumar Jha
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, India
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10
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Furuchi T, Sakurako K, Katane M, Sekine M, Homma H. The role of protein L-isoaspartyl/D-aspartyl O-methyltransferase (PIMT) in intracellular signal transduction. Chem Biodivers 2010; 7:1337-48. [PMID: 20564550 DOI: 10.1002/cbdv.200900273] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Under physiological conditions, L-aspartyl (L-Asp) and L-asparaginyl residues in proteins are spontaneously isomerized or racemized to D-aspartyl (D-Asp) or D,L-isoaspartyl (D,L-isoAsp) residue. These atypical Asp residues can interfere with protein activity and lead to disruption of cellular function. Protein L-isoaspartyl/D-aspartyl O-methyltransferase (PIMT) is a repair enzyme that initiates the conversion of L-isoAsp (or D-Asp) residues to L-Asp residues. PIMT-Deficient mice exhibit accumulation of L-isoAsp in several tissues and die from progressive epileptic seizures at a mean age of 42 days. However, the biological roles of PIMT are still largely unknown. To further our understanding of the function of this protein, we developed an assay to measure PIMT activity in cell lysates. Additionally, we generated PIMT-knockdown cells by stable transfection of HEK293 cells with PIMT small interfering (si) RNA. Northern blotting and immunoblot analysis revealed that PIMT mRNA and protein levels were significantly decreased in the knockdown cells. In addition, significant levels of proteins that contained isoAsp residues accumulated in these cells, and immunoblot analysis revealed that Raf-1, MEK, and ERK were hyperphosphorylated upon EGF stimulation compared to control cells. These results indicate that the ability to repair atypical Asp residues is important for normal MAP kinase signaling.
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Affiliation(s)
- Takemitsu Furuchi
- Laboratory of Biomolecular Science, Department of Pharmaceutical Life Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
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11
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Graziano G, Notomista E, Catanzano F, Barone G, Donato AD. Thermal Stability of Onconase and Some Mutant Forms. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.3109/10242420108992030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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12
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Chapter 16 Analysis of Deamidation in Proteins. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s0166-526x(08)00216-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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13
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Zhou XX, Wang YB, Pan YJ, Li WF. Differences in amino acids composition and coupling patterns between mesophilic and thermophilic proteins. Amino Acids 2007; 34:25-33. [PMID: 17710363 DOI: 10.1007/s00726-007-0589-x] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Accepted: 07/12/2007] [Indexed: 10/22/2022]
Abstract
Thermophilic proteins show substantially higher intrinsic thermal stability than their mesophilic counterparts. Amino acid composition is believed to alter the intrinsic stability of proteins. Several investigations and mutagenesis experiment have been carried out to understand the amino acid composition for the thermostability of proteins. This review presents some generalized features of amino acid composition found in thermophilic proteins, including an increase in residue hydrophobicity, a decrease in uncharged polar residues, an increase in charged residues, an increase in aromatic residues, certain amino acid coupling patterns and amino acid preferences for thermophilic proteins. The differences of amino acids composition between thermophilic and mesophilic proteins are related to some properties of amino acids. These features provide guidelines for engineering mesophilic protein to thermophilic protein.
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Affiliation(s)
- X-X Zhou
- Institute of Chemical Biology and Pharmaceutical Chemistry, Zhejiang University, Hangzhou, China
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14
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Zabrouskov V, Han X, Welker E, Zhai H, Lin C, van Wijk KJ, Scheraga HA, McLafferty FW. Stepwise deamidation of ribonuclease A at five sites determined by top down mass spectrometry. Biochemistry 2006; 45:987-92. [PMID: 16411774 PMCID: PMC2515934 DOI: 10.1021/bi0517584] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although deamidation at asparagine and glutamine has been found in numerous studies of a variety of proteins, in almost all cases the analytical methodology that was used could detect only a single site of deamidation. For the extensively studied case of reduced bovine ribonuclease A (13,689 Da), only Asn67 deamidation has been demonstrated previously, although one study found three monodeamidated fractions. Here top down tandem mass spectrometry shows that Asn67 deamidation is extensive before Asn71 and Asn94 react; these are more than half deamidated before Asn34 reacts, and its deamidation is extensive before that at Gln74 is initiated. Except for the initial Asn67 site, these large reactivity differences correlate poorly with neighboring amino acid identities and instead indicate residual conformational effects despite the strongly denaturing media that were used; deamidation at Asn67 could enhance that at Asn71, and these enhance that at Gln74. This success in the site-specific quantitation of deamidation in a 14 kDa protein mixture, despite the minimal 1 Da (-NH2 --> -OH) change in the molecular mass, is further evidence of the broad applicability of the top down MS/MS methodology for characterization of protein posttranslational modifications.
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Affiliation(s)
- Vlad Zabrouskov
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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15
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Celej MS, Dassie SA, González M, Bianconi ML, Fidelio GD. Differential scanning calorimetry as a tool to estimate binding parameters in multiligand binding proteins. Anal Biochem 2006; 350:277-84. [PMID: 16434020 DOI: 10.1016/j.ab.2005.12.029] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2005] [Revised: 12/15/2005] [Accepted: 12/18/2005] [Indexed: 11/21/2022]
Abstract
The stability of proteins and their interactions with other molecules is a topic of special interest in biochemistry because many cellular processes depend on that. New methods and approaches are constantly developed to elucidate the energetics of biomolecular recognition. In this sense, the application of the theory of macromolecular unfolding linked to ligand binding to differential scanning calorimetry (DSC) has proved to be a useful tool to simultaneously characterize the energetics of unfolding and binding. Although the general theory is well known, the applicability of DSC to study the interaction of biomolecules is not common. In the current work, we estimated the binding parameters of 8-anilinonaphthalene-1-sulfonic acid to human serum albumin using DSC. This model system was chosen due to both the complex stoichiometry and the moderate binding constants. From DSC curves acquired at different ligand concentrations, we obtained the number of bound ligands, the binding constants, and the binding enthalpy for each independent binding site. Compared with those parameters determined by titration calorimetry, the results highlight the potentiality of DSC to estimate binding parameters in multiligand binding proteins.
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Affiliation(s)
- M Soledad Celej
- Departamento de Química Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina.
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16
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Picone D, Di Fiore A, Ercole C, Franzese M, Sica F, Tomaselli S, Mazzarella L. The role of the hinge loop in domain swapping. The special case of bovine seminal ribonuclease. J Biol Chem 2005; 280:13771-8. [PMID: 15647261 DOI: 10.1074/jbc.m413157200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Bovine seminal ribonuclease (BS-RNase) is a covalent homodimeric enzyme homologous to pancreatic ribonuclease (RNase A), endowed with a number of special biological functions. It is isolated as an equilibrium mixture of swapped (MxM) and unswapped (M=M) dimers. The interchanged N termini are hinged on the main bodies through the peptide 16-22, which changes conformation in the two isomers. At variance with other proteins, domain swapping in BS-RNase involves two dimers having a similar and highly constrained quaternary association, mainly dictated by two interchain disulfide bonds. This provides the opportunity to study the intrinsic ability to swap as a function of the hinge sequence, without additional effects arising from dissociation or quaternary structure modifications. Two variants, having Pro19 or the whole sequence of the hinge replaced by the corresponding residues of RNase A, show equilibrium and kinetic parameters of the swapping similar to those of the parent protein. In comparison, the x-ray structures of MxM indicate, within a substantial constancy of the quaternary association, a greater mobility of the hinge residues. The relative insensitivity of the swapping tendency to the substitutions in the hinge region, and in particular to the replacement of Pro19 by Ala, contrasts with the results obtained for other swapped proteins and can be rationalized in terms of the unique features of the seminal enzyme. Moreover, the results indirectly lend credit to the hypothesis that the major role of Pro19 resides in directing the assembly of the non-covalent dimer, the species produced by selective reduction of the interchain disulfides and considered responsible for the special biological functions of BS-RNase.
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Affiliation(s)
- Delia Picone
- Dipartimento di Chimica, Università Federico II di Napoli, Via Cynthia, 80126, Napoli, Italy
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17
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Lee CK, Pugh TD, Klopp RG, Edwards J, Allison DB, Weindruch R, Prolla TA. The impact of alpha-lipoic acid, coenzyme Q10 and caloric restriction on life span and gene expression patterns in mice. Free Radic Biol Med 2004; 36:1043-57. [PMID: 15059645 DOI: 10.1016/j.freeradbiomed.2004.01.015] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2003] [Revised: 01/07/2004] [Accepted: 01/23/2004] [Indexed: 11/25/2022]
Abstract
We evaluated the efficacy of three dietary interventions started at middle age (14 months) to retard the aging process in mice. These were supplemental alpha-lipoic acid (LA) or coenzyme Q(10) (CQ) and caloric restriction (CR, a positive control). LA and CQ had no impact on longevity or tumor patterns compared with control mice fed the same number of calories, whereas CR increased maximum life span by 13% (p <.0001) and reduced tumor incidence. To evaluate these interventions at the molecular level, we used microarrays to monitor the expression of 9977 genes in hearts from young (5 months) and old (30 months) mice. LA, CQ, and CR inhibited age-related alterations in the expression of genes involved in the extracellular matrix, cellular structure, and protein turnover. However, unlike CR, LA and CQ did not prevent age-related transcriptional alterations associated with energy metabolism. LA supplementation lowered the expression of genes encoding major histocompatibility complex components and of genes involved in protein turnover and folding. CQ increased expression of genes involved in oxidative phosphorylation and reduced expression of genes involved in the complement pathway and several aspects of protein function. Our observations suggest that supplementation with LA or CQ results in transcriptional alterations consistent with a state of reduced oxidative stress in the heart, but that these dietary interventions are not as effective as CR in inhibiting the aging process in the heart.
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Affiliation(s)
- Cheol-Koo Lee
- Molecular and Environmental Toxicology Center, University of Wisconsin, Madison, WI 53706, USA
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18
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Gotte G, Libonati M, Laurents DV. Glycosylation and specific deamidation of ribonuclease B affect the formation of three-dimensional domain-swapped oligomers. J Biol Chem 2003; 278:46241-51. [PMID: 12966091 DOI: 10.1074/jbc.m308470200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RNase A oligomerizes via the three-dimensional domain-swapping mechanism to form a variety of oligomers, including two dimers. One, called the N-dimer, forms by swapping of the N termini of the protein; the other, called the C-dimer, forms by swapping of the C termini. RNase B is identical in protein sequence and conformation to RNase A, but its Asn34 bears an oligosaccharide chain that might affect oligomerization. The ability of RNase B to oligomerize under two sets of conditions has been examined. The amount of oligomers formed via lyophilization was somewhat lower for RNase B than RNase A, and RNase B oligomerized more rapidly in 40% ethanol solution at high temperature than RNase A. The ratio of the N-dimer to C-dimer formed increased with the size of the carbohydrate chain under both sets of conditions. These results suggest that the oligosaccharide chain either favors productive collisions or stabilizes the oligomers, especially the N-dimer. Endoglycosidase H treatment of RNase B partially restored RNase A-like oligomerization. Derivatives of RNase A conjugated at the amine groups to polyethylene glycol chains showed a greatly reduced capacity for oligomerization, suggesting that oligomerization can be impeded sterically. Commercial preparations of RNase B eluted as two main peaks by cation exchange chromatography. Using chromatography, mass spectroscopy, and two-dimensional NMR, the major peak was identified as RNase B selectively deamidated at Asn67. This deamidated protein showed a >4 degrees C drop in thermal stability, disruption of the native structure of residues 67-69, and a decreased ability to oligomerize compared with unmodified RNase B.
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Affiliation(s)
- Giovanni Gotte
- Dipartimento di Scienze Neurologiche e della Visione, Sezione di Chimica Biologica, Facoltà di Medicina e Chirurgia, Università di Verona, Strada Le Grazie 8, I-37134 Verona, Italy
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19
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20
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Shogen, PhD K, Saxena, PhD SK, Ardelt, PhD W. ONCONASE ® and Its Therapeutic Potential. Lab Med 2003. [DOI: 10.1309/3td2-6gxn-65ge-c1bg] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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21
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Lakemond CMM, De Jongh HHJ, Gruppen H, Voragen AGJ. Differences in denaturation of genetic variants of soy glycinin. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2002; 50:4275-81. [PMID: 12105958 DOI: 10.1021/jf0110405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In heat denaturation studies conducted in the past the genetic variants of glycinin have been considered as a homogeneous group of proteins. In this work the validity of this assumption was tested. It was found by calorimetric studies that glycinin denatures heterogeneously at pH 7.6. When the temperature of isothermal treatment is increased from 70 to 82 degrees C the proportion of glycinin remaining native progressively decreases from 95% to 5% while the denaturation temperature of the glycinin remaining native increases from 88.5 to 95 degrees C. Similar trends were found for pH 3.8. Fractionation and subsequent analysis (MALDI-TOF and CE) of isothermally treated samples demonstrated that at pH 7.6 the heterogeneous denaturation is caused by differences in thermal stability of the genetic variants of glycinin. The stability increases in the order G2/G3/G1< A(4)< G5 < G4.
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22
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Abstract
At acidic pH, Asp67 and beta-Asp67 (beta-Asp: isoaspartic acid residue) derivatives of RNase A, obtained by selective deamidation of the parent enzyme, spontaneously produces a new derivative containing an aminosuccinyl residue (Asu). The overall secondary structure of the protein chain does not change as a consequence of this substitution, while the catalytic activity on RNA is reduced to about 25%. The pH dependence of the first-order rate constants for the Asu formation has a bell-shaped profile, the maximum being close to the pK(a) of the aspartic acid side chains. Moreover, the values of the rate constants are of the same magnitude of those measured for Asp-containing peptides whose sequence mimics the Asu formation site of the enzyme. This feature indicates that Asp67 and beta-Asp67 residues in the deamidated RNase A derivatives are sited in a region flexible enough to permit the cyclization of the carboxylic side chain to succinimide ring. These results are discussed at the light on to the three-dimensional structure and the thermodynamic stability of the aspartic acid derivatives of RNase A.
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Affiliation(s)
- S Capasso
- Dipartimento di Scienze Ambientali, Seconda Università di Napoli, Caserta, Italy.
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23
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Chatani E, Hayashi R. Functional and structural roles of constituent amino acid residues of bovine pancreatic ribonuclease A. J Biosci Bioeng 2001. [DOI: 10.1016/s1389-1723(01)80208-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Capasso S, Di Cerbo P. Kinetic and thermodynamic control of the relative yield of the deamidation of asparagine and isomerization of aspartic acid residues. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 2000; 56:382-7. [PMID: 11152297 DOI: 10.1034/j.1399-3011.2000.00778.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Selective deamidation of Asn67 of RNase A to beta-Asp67 and Asp67 residues at neutral pH initially produces greater amounts of the beta-Asp derivative. As the reaction proceeds the relative concentration of [Asp67]-RNase A increases and, at equilibrium, becomes predominant. Such a discrepancy between the kinetic and thermodynamic control on reaction products is discussed in light of information from X-ray three-dimensional analysis and the lower thermodynamic stability of the beta-Asp derivative relative to the parent enzyme.
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Affiliation(s)
- S Capasso
- Dipartimento di Scienze Ambientali, Seconda Università di Napoli, Caserta, Italy.
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25
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Esposito L, Vitagliano L, Sica F, Sorrentino G, Zagari A, Mazzarella L. The ultrahigh resolution crystal structure of ribonuclease A containing an isoaspartyl residue: hydration and sterochemical analysis. J Mol Biol 2000; 297:713-32. [PMID: 10731423 DOI: 10.1006/jmbi.2000.3597] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Crystals of the deamidated form of bovine pancreatic ribonuclease which contains an isoaspartyl residue in position 67 diffract to 0. 87 A at 100 K. We have refined the crystallographic model using anisotropic displacement parameters for all atoms to a conventional crystallographic residual R=0.101 for all observed reflections in the resolution range 61.0-0.87 A. The ratio observations/parameters is 7.2 for the final model. This structure represents one of the highest resolution protein structures to date and interestingly, it is the only example containing more than one molecule in the asymmetric unit with a resolution better than 1.0 A. The non-crystallographic symmetry has been used as a validation check of the geometrical parameters and it has allowed an estimate for an upper limit of errors associated with this high resolution model. In the present structure it was possible to obtain a more accurate picture of the active site whose electron density was not clearly interpretable in the previous 1.9 A resolution structure. In particular, the P1 site is alternatively occupied either by a sulphate anion or by a water molecule network. Most of hydrogen atoms were visible in the electron density maps, including those involved in C(alpha)-H(alpha).O interactions. Analysis of protein-solvent interactions has revealed the occurrence of an extensive cluster of water molecules, predominantly arranged in pentagonal fused rings and surrounding hydrophobic moiety of side-chains. Finally, in spite of the limited sample of residues, we have detected a clear dependence of backbone N-C(alpha)-C angle on residue conformation. This correlation can be fruitfully used as a valuable tool in protein structure validation.
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Affiliation(s)
- L Esposito
- Centro di Studio di Biocristallografia, CNR and Dipartimento di Chimica Università di Napoli "Federico II", Via Mezzocannone 4 I-80134, Napoli, Italy
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26
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Capasso S, Salvadori S. Effect of the three-dimensional structure on the deamidation reaction of ribonuclease A. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 1999; 54:377-82. [PMID: 10563503 DOI: 10.1034/j.1399-3011.1999.00111.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Kinetic data on the deamidation reaction of Asn67 in RNase A and of Asn3 in the two peptides Ac-Cys-Lys-Asn-Gly-Gln-Thr-Asn-Cys-NH2 and Ac-Cys(Me)-Lys-Asn-Gly-Gln-Thr-Asn-Cys(Me)-NH2, whose sequences are similar to that of the deamidation site in the enzyme, have been determined in a wide range of pH and buffer concentrations. The values of the observed rate constant (k) for the enzyme are markedly lower than those for the peptides. However, the k dependence on pH and buffers is similar for all three substrates, indicating a similar reaction mechanism. The lower k-values for the enzyme have been quantitatively related to the thermal stability and the three-dimensional structure of the enzyme.
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Affiliation(s)
- S Capasso
- Dipatimento di Scienze Ambientali, Seconda Università di Napoli, Caserta, Centro di Studio di Biocristallografia, CNR, Italy.
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27
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Graziano G, Catanzano F, Nappa M. Linkage of proton binding to the thermal unfolding of Sso7d from the hyperthermophilic archaebacterium Sulfolobus solfataricus. Int J Biol Macromol 1999; 26:45-53. [PMID: 10520955 DOI: 10.1016/s0141-8130(99)00059-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In this study the pH dependence of the thermal stability of Sso7d from Sulfolobus solfataricus is analyzed. This small globular protein of 63 residues shows a very marked dependence of thermal stability on pH: the denaturation temperature passes from 65.2 degrees C at pH 2.5 to 97.9 degrees C at pH 4.5. Analysis of the data points out that the binding of at least two protons is coupled to the thermal unfolding. By linking the proton binding to the conformational unfolding equilibrium, a thermodynamic model, which is able to describe the dependence upon the solution pH of both the excess heat capacity function and the denaturation Gibbs energy change for Sso7d, is developed. The decreased stability in very acid conditions is due to the binding of two protons on identical and noninteracting sites of the unfolded state. Actually, such sites are two carboxyl groups possessing very low pKa values in the native structure, probably involved in salt-bridges on the protein surface.
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Affiliation(s)
- G Graziano
- Department of Chemistry, University of Naples Federico II, Italy.
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28
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Kim E, Lowenson JD, Clarke S, Young SG. Phenotypic analysis of seizure-prone mice lacking L-isoaspartate (D-aspartate) O-methyltransferase. J Biol Chem 1999; 274:20671-8. [PMID: 10400700 DOI: 10.1074/jbc.274.29.20671] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Within proteins and peptides, both L-asparaginyl and L-aspartyl residues spontaneously degrade, generating isomerized and racemized aspartyl residues. The enzyme protein L-isoaspartate (D-aspartate) O-methyltransferase (E.C. 2.1.1.77) initiates the conversion of L-isoaspartyl and D-aspartyl residues to normal L-aspartyl residues. This "repair" reaction helps to maintain proper protein conformation by preventing the accumulation of damaged proteins containing abnormal amino acid residues. Pcmt1-/- mice manifest two key phenotypes: a fatal seizure disorder and retarded growth. In this study, we characterized both phenotypes and demonstrated that they are linked. Continuous electroencephalogram monitoring of Pcmt1-/- mice revealed that abnormal cortical activity for approximately 50% of each 24-h period, even in mice that had no visible evidence of convulsions. The fatal seizure disorder in Pcmt1-/- mice can be mitigated but not eliminated by antiepileptic drugs. Interestingly, antiepileptic therapy normalized the growth of Pcmt1-/- mice, suggesting that the growth retardation is due to seizures rather than a global disturbance in growth at the cellular level. Consistent with this concept, the growth rate of Pcmt1-/- fibroblasts was indistinguishable from that of wild-type fibroblasts.
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Affiliation(s)
- E Kim
- Gladstone Institute of Cardiovascular Disease, San Francisco, California 94141-9100, USA.
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29
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Abstract
The change in heat capacity deltaCp for the folding of ribonuclease A was determined using differential scanning calorimetry and thermal denaturation curves. The methods gave equivalent results, deltaCp = 1.15+/-0.08 kcal mol(-1) K(-1). Estimates of the conformational stability of ribonuclease A based on these results from thermal unfolding are in good agreement with estimates from urea unfolding analyzed using the linear extrapolation method.
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Affiliation(s)
- C N Pace
- Department of Medical Biochemistry and Genetics, Texas A&M University, College Station 77843-1114, USA.
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30
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Niewmierzycka A, Clarke S. Do damaged proteins accumulate in Caenorhabditis elegans L-isoaspartate methyltransferase (pcm-1) deletion mutants? Arch Biochem Biophys 1999; 364:209-18. [PMID: 10190976 DOI: 10.1006/abbi.1999.1114] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The protein l-isoaspartate (d-aspartate) O-methyltransferase (E.C. 2. 1.1.77) can initiate the conversion of isomerized and racemized aspartyl residues to their normal l-aspartyl forms and has therefore been hypothesized to function as a repair enzyme, responsible for helping to limit the accumulation of damaged proteins in aging organisms. In this study, the effect of a disruption in the pcm-1 gene encoding the l-isoaspartyl methyltransferase was investigated in the nematode Caenorhabditis elegans. It was found that damaged proteins recognized by this enzyme accumulated to significant levels during long-term incubation of both pcm-1+ and pcm-1- nematodes in a specialized larval stage called the dauer. The l-isoaspartyl methyltransferase-deficient mutants accumulated about twice the level of damaged proteins as the control nematodes during dauer aging. The mutants also accumulated higher levels of damage when both strains were incubated at 30 degrees C for up to 3 days. However, when nonviable nematodes were removed in a Percoll separation, similar levels of damage were measured between the two strains following both dauer aging and 30 degrees C incubation. Both strains were able to effectively eliminate damaged proteins recognized by the methyltransferase after recovery from dauer. Characterization of the methyl-accepting polypeptide substrates which accumulate in aged dauers revealed that although substrates of all molecular weights are present, the majority of substrates are peptides not precipitated by acetone. These results suggest that protein degradation, rather than repair, may be the major mechanism by which C. elegans eliminates damaged proteins containing l-isoaspartyl residues.
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Affiliation(s)
- A Niewmierzycka
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, California, 90095-1569, USA
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31
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Abstract
Three complete genome sequences of thermophilic bacteria provide a wealth of information challenging current ideas concerning phylogeny and evolution, as well as the determinants of protein stability. Considering known protein structures from extremophiles, it becomes clear that no general conclusions can be drawn regarding adaptive mechanisms to extremes of physical conditions. Proteins are individuals that accumulate increments of stabilization; in thermophiles these come from charge clusters, networks of hydrogen bonds, optimization of packing and hydrophobic interactions, each in its own way. Recent examples indicate ways for the rational design of ultrastable proteins.
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Affiliation(s)
- R Jaenicke
- Institute of Biophysics and Physical Biochemistry University of Regensburg D-93040 Regensburg Germany. rainer.jaenicke@biologie. uni-regensburg.de
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32
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Catanzano F, Graziano G, Cafaro V, D'Alessio G, Di Donato A, Barone G. Circular dichroism study of ribonuclease A mutants containing the minimal structural requirements for dimerization and swapping. Int J Biol Macromol 1998; 23:277-85. [PMID: 9849625 DOI: 10.1016/s0141-8130(98)00060-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Four residues Pro19. Leu28, Cys31 and Cys32 proved to be the minimal structural requirements in determining the dimeric structure and the N-terminal segment swapping of bovine seminal ribonuclease, BS-RNase. We analyzed the content of secondary and tertiary structures in RNase A, P-RNase A, PL-RNase A, MCAM-PLCC-RNase A and MCAM-BS-RNase, performing near and far-UV CD spectra. It results that the five proteins have very similar native conformations. Thermal denaturation at pH 5.0 of the proteins. studied by means of CD measurements. proved reversible and well represented by the two-state N<==>D transition model. Thermodynamic data are discussed in the light of the structural information available for RNase A and BS-RNase.
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Affiliation(s)
- F Catanzano
- Dipartimento di Chimica, Università di Napoli Federico II, Italy
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33
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Pace CN, Hebert EJ, Shaw KL, Schell D, Both V, Krajcikova D, Sevcik J, Wilson KS, Dauter Z, Hartley RW, Grimsley GR. Conformational stability and thermodynamics of folding of ribonucleases Sa, Sa2 and Sa3. J Mol Biol 1998; 279:271-86. [PMID: 9636716 DOI: 10.1006/jmbi.1998.1760] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ribonucleases Sa, Sa2, and Sa3 are three small, extracellular enzymes produced by different strains of Streptomyces aureofaciens with amino acid sequences that are 50% identical. We have studied the unfolding of these enzymes by heat and urea to determine the conformational stability and its dependence on temperature, pH, NaCl, and the disulfide bond. All three of the Sa ribonucleases unfold reversibly by a two-state mechanism with melting temperatures, Tm, at pH 7 of 48.4 degrees C (Sa), 41.1 degrees C (Sa2), and 47.2 degrees C (Sa3). The Tm values are increased in the presence of 0.5 M NaCl by 4.0 deg. C (Sa), 0.1 deg. C (Sa2), and 7.2 deg. C (Sa3). The Tm values are decreased by 20.0 deg. C (Sa), 31.5 deg. C (Sa2), and 27.0 deg. C (Sa3) when the single disulfide bond in the molecules is reduced. We compare these results with similar studies on two other members of the microbial ribonuclease family, RNase T1 and RNase Ba (barnase), and with a member of the mammalian ribonuclease family, RNase A. At pH 7 and 25 degrees C, the conformational stabilities of the ribonucleases are (kcal/mol): 2.9 (Sa2), 5.6 (Sa3), 6.1 (Sa), 6.6 (T1), 8.7 (Ba), and 9.2 (A). Our analysis of the stabilizing forces suggests that the hydrophobic effect contributes from 90 to 110 kcal/mol and that hydrogen bonding contributes from 70 to 105 kcal/mol to the stability of these ribonucleases. Thus, we think that the hydrophobic effect and hydrogen bonding make large but comparable contributions to the conformational stability of these proteins.
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Affiliation(s)
- C N Pace
- Department of Medical Biochemistry and Genetics, Texas A&M University, College Station 77843, USA
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34
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Affiliation(s)
- Ronald T. Raines
- Departments of Biochemistry and Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
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