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Miyazono KI, Wang D, Ito T, Tanokura M. Crystal structure and DNA cleavage mechanism of the restriction DNA glycosylase R.CcoLI from Campylobacter coli. Sci Rep 2021; 11:859. [PMID: 33441677 PMCID: PMC7806768 DOI: 10.1038/s41598-020-79537-y] [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: 07/16/2020] [Accepted: 12/09/2020] [Indexed: 11/09/2022] Open
Abstract
While most restriction enzymes catalyze the hydrolysis of phosphodiester bonds at specific nucleotide sequences in DNA, restriction enzymes of the HALFPIPE superfamily cleave N-glycosidic bonds, similar to DNA glycosylases. Apurinic/apyrimidinic (AP) sites generated by HALFPIPE superfamily proteins are cleaved by their inherent AP lyase activities, other AP endonuclease activities or heat-promoted β-elimination. Although the HALFPIPE superfamily protein R.PabI, obtained from a hyperthermophilic archaea, Pyrococcus abyssi, shows weak AP lyase activity, HALFPIPE superfamily proteins in mesophiles, such as R.CcoLI from Campylobacter coli and R. HpyAXII from Helicobacter pylori, show significant AP lyase activities. To identify the structural basis for the AP lyase activity of R.CcoLI, we determined the structure of R.CcoLI by X-ray crystallography. The structure of R.CcoLI, obtained at 2.35-Å resolution, shows that a conserved lysine residue (Lys71), which is stabilized by a characteristic β-sheet structure of R.CcoLI, protrudes into the active site. The results of mutational assays indicate that Lys71 is important for the AP lyase activity of R.CcoLI. Our results help to elucidate the mechanism by which HALFPIPE superfamily proteins from mesophiles efficiently introduce double-strand breaks to specific sites on double-stranded DNA.
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Affiliation(s)
- Ken-Ichi Miyazono
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Delong Wang
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Tomoko Ito
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Masaru Tanokura
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi Bunkyo-ku, Tokyo, 113-8657, Japan.
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2
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Liu X, Liu T, Zhang Y, Xin F, Mi S, Wen B, Gu T, Shi X, Wang F, Sun L. Structural Insights into the Thermophilic Adaption Mechanism of Endo-1,4-β-Xylanase from Caldicellulosiruptor owensensis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:187-193. [PMID: 29236500 DOI: 10.1021/acs.jafc.7b03607] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Xylanases (EC 3.2.1.8) are a kind of enzymes degrading xylan to xylooligosaccharides (XOS) and have been widely used in a variety of industrial applications. Among them, xylanases from thermophilic microorganisms have distinct advantages in industries that require high temperature conditions. The CoXynA gene, encoding a glycoside hydrolase (GH) family 10 xylanase, was identified from thermophilic Caldicellulosiruptor owensensis and was overexpressed in Escherichia coli. Recombinant CoXynA showed optimal activity at 90 °C with a half-life of about 1 h at 80 °C and exhibited highest activity at pH 7.0. The activity of CoXynA activity was affected by a variety of cations. CoXynA showed distinct substrate specificities for beechwood xylan and birchwood xylan. The crystal structure of CoXynA was solved and a molecular dynamics simulation of CoXynA was performed. The relatively high thermostability of CoXynA was proposed to be due to the increased overall protein rigidity resulting from the reduced length and fluctuation of Loop 7.
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Affiliation(s)
- Xin Liu
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Tengfei Liu
- School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing 100102, P.R. China
| | - Yuebin Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , 457 Zhongshan Rd, Dalian 116023, P.R. China
| | - Fengjiao Xin
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Shuofu Mi
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences , Beijing 100190, P.R. China
| | - Boting Wen
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Tianyi Gu
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Xinyuan Shi
- School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing 100102, P.R. China
| | - Fengzhong Wang
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Lichao Sun
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
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Liszka MJ, Clark ME, Schneider E, Clark DS. Nature Versus Nurture: Developing Enzymes That Function Under Extreme Conditions. Annu Rev Chem Biomol Eng 2012; 3:77-102. [DOI: 10.1146/annurev-chembioeng-061010-114239] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - Elizabeth Schneider
- Department of Chemical and Biomolecular Engineering,
- UC Berkeley and UCSF Graduate Program in Bioengineering, University of California, Berkeley, California 94720; , , ,
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4
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Arad-Haase G, Chuartzman SG, Dagan S, Nevo R, Kouza M, Mai BK, Nguyen HT, Li MS, Reich Z. Mechanical unfolding of acylphosphatase studied by single-molecule force spectroscopy and MD simulations. Biophys J 2010; 99:238-47. [PMID: 20655852 PMCID: PMC2895382 DOI: 10.1016/j.bpj.2010.04.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 03/28/2010] [Accepted: 04/01/2010] [Indexed: 11/30/2022] Open
Abstract
Single-molecule manipulation methods provide a powerful means to study protein transitions. Here we combined single-molecule force spectroscopy and steered molecular-dynamics simulations to study the mechanical properties and unfolding behavior of the small enzyme acylphosphatase (AcP). We find that mechanical unfolding of AcP occurs at relatively low forces in an all-or-none fashion and is decelerated in the presence of a ligand, as observed in solution measurements. The prominent energy barrier for the transition is separated from the native state by a distance that is unusually long for alpha/beta proteins. Unfolding is initiated at the C-terminal strand (beta(T)) that lies at one edge of the beta-sheet of AcP, followed by unraveling of the strand located at the other. The central strand of the sheet and the two helices in the protein unfold last. Ligand binding counteracts unfolding by stabilizing contacts between an arginine residue (Arg-23) and the catalytic loop, as well as with beta(T) of AcP, which renders the force-bearing units of the protein resistant to force. This stabilizing effect may also account for the decelerated unfolding of ligand-bound AcP in the absence of force.
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Affiliation(s)
- Gali Arad-Haase
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Silvia G. Chuartzman
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Shlomi Dagan
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Reinat Nevo
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Maksim Kouza
- Department of Physics, Michigan Technological University, Houghton, Michigan
| | - Binh Khanh Mai
- Saigon Institute for Computational Science and Technology, Ho Chi Minh City, Vietnam
| | - Hung Tien Nguyen
- Saigon Institute for Computational Science and Technology, Ho Chi Minh City, Vietnam
| | - Mai Suan Li
- Institute of Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Ziv Reich
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
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5
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Hu J, Li D, Su XD, Jin C, Xia B. Solution structure and conformational heterogeneity of acylphosphatase from Bacillus subtilis. FEBS Lett 2010; 584:2852-6. [PMID: 20447399 DOI: 10.1016/j.febslet.2010.04.069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 04/26/2010] [Accepted: 04/26/2010] [Indexed: 10/19/2022]
Abstract
Acylphosphatase is a small enzyme that catalyzes the hydrolysis of acyl phosphates. Here, we present the solution structure of acylphosphatase from Bacillus subtilis (BsAcP), the first from a Gram-positive bacterium. We found that its active site is disordered, whereas it converted to an ordered state upon ligand binding. The structure of BsAcP is sensitive to pH and it has multiple conformations in equilibrium at acidic pH (pH<5.8). Only one main conformation could bind ligand, and the relative population of these states is modulated by ligand concentration. This study provides direct evidence for the role of ligand in conformational selection.
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Affiliation(s)
- Jicheng Hu
- Beijing Nuclear Magnetic Resonance Center, Peking University, Beijing, China
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Miyazono KI, Shirokane M, Sawano Y, Tanokura M. Crystal structure of the DUF54 family protein PH1010 from hyperthermophilic archaea Pyrococcus horikoshii OT3. Proteins 2009; 74:256-60. [PMID: 18831045 DOI: 10.1002/prot.22255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ken-ichi Miyazono
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
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7
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Bemporad F, Vannocci T, Varela L, Azuaga AI, Chiti F. A model for the aggregation of the acylphosphatase from Sulfolobus solfataricus in its native-like state. BIOCHIMICA ET BIOPHYSICA ACTA 2008; 1784:1986-96. [PMID: 18832052 DOI: 10.1016/j.bbapap.2008.08.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Revised: 08/19/2008] [Accepted: 08/21/2008] [Indexed: 11/15/2022]
Abstract
Evidence is accumulating that normally folded proteins retain a significant tendency to form amyloid fibrils through a direct assembly of monomers in their native-like conformation. However, the factors promoting such processes are not yet well understood. The acylphosphatase from Sulfolobus solfataricus (Sso AcP) aggregates under conditions in which a native-like state is initially populated and forms, as a first step, aggregates in which the monomers maintain their native-like topology. An unstructured N-terminal segment and an edge beta-strand were previously shown to play a major role in the process. Using kinetic experiments on a set of Sso AcP variants we shall show that the major event of the first step is the establishment of an inter-molecular interaction between the unstructured segment of one Sso AcP molecule and the globular unit of another molecule. This interaction is determined by the primary sequence of the unstructured segment and not by its physico-chemical properties. Moreover, we shall show that the conversion of these initial aggregates into amyloid-like protofibrils is an intra-molecular process in which the Sso AcP molecules undergo conformational modifications. The obtained results allow the formulation of a model for the assembly of Sso AcP into amyloid-like aggregates at a molecular level.
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Affiliation(s)
- Francesco Bemporad
- Department of Biochemical Sciences, University of Florence, Viale Morgagni 50, Florence 50134, Italy
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8
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Parrini C, Bemporad F, Baroncelli A, Gianni S, Travaglini-Allocatelli C, Kohn JE, Ramazzotti M, Chiti F, Taddei N. The folding process of acylphosphatase from Escherichia coli is remarkably accelerated by the presence of a disulfide bond. J Mol Biol 2008; 379:1107-18. [PMID: 18495159 DOI: 10.1016/j.jmb.2008.04.051] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 04/21/2008] [Accepted: 04/23/2008] [Indexed: 11/30/2022]
Abstract
The acylphosphatase from Escherichia coli (EcoAcP) is the first AcP so far studied with a disulfide bond. A mutational variant of the enzyme lacking the disulfide bond has been produced by substituting the two cysteine residues with alanine (EcoAcP mutational variant C5A/C49A, mutEcoAcP). The native states of the two protein variants are similar, as shown by far-UV and near-UV circular dichroism and dynamic light-scattering measurements. From unfolding experiments at equilibrium using intrinsic fluorescence and far-UV circular dichroism as probes, EcoAcP shows an increased conformational stability as compared with mutEcoAcP. The wild-type protein folds according to a two-state model with a very fast rate constant (k(F)(H2O)=72,600 s(-1)), while mutEcoAcP folds ca 1500-fold slower, via the accumulation of a partially folded species. The correlation between the hydrophobicity of the polypeptide chain and the folding rate, found previously in the AcP-like structural family, is maintained only when considering the mutant but not the wild-type protein, which folds much faster than expected from this correlation. Similarly, the correlation between the relative contact order and the folding rate holds only for mutEcoAcP. The correlation also holds for EcoAcP, provided the relative contact order value is recalculated by considering the disulfide bridge as an alternate path for the backbone to determine the shortest sequence separation between contacting residues. These results indicate that the presence of a disulfide bond in a protein is an important determinant of the folding rate and allows its contribution to be determined in quantitative terms.
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Affiliation(s)
- Claudia Parrini
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Viale Morgagni 50, 50134 Firenze, Italy
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9
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Bemporad F, Gsponer J, Hopearuoho HI, Plakoutsi G, Stati G, Stefani M, Taddei N, Vendruscolo M, Chiti F. Biological function in a non-native partially folded state of a protein. EMBO J 2008; 27:1525-35. [PMID: 18451804 PMCID: PMC2396399 DOI: 10.1038/emboj.2008.82] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Accepted: 03/31/2008] [Indexed: 11/09/2022] Open
Abstract
As structural flexibility is known to be required for enzyme catalysis and pattern recognition and a significant fraction of eukaryotic proteins appear to be unfolded or contain unstructured regions, biological activity of conformational states distinct from fully folded structures could be more common than previously thought. By applying a procedure that allows the recovery of enzymatic activity to be monitored in real time, we show that a non-native state populated transiently during folding of the acylphosphatase from Sulfolobus solfataricus is enzymatically active. The structural characterization of this partially folded state reveals that enzymatic activity is possible even if the catalytic site is structurally heterogeneous, whereas the remainder of the structure acts as a scaffold. These results extend the spectrum of biological functions carried out in the absence of a folded state to include enzyme catalysis.
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Affiliation(s)
- Francesco Bemporad
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Firenze, Italy
| | - Joerg Gsponer
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | | | - Georgia Plakoutsi
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Firenze, Italy
| | - Gianmarco Stati
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Firenze, Italy
| | - Massimo Stefani
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Firenze, Italy
| | - Niccolò Taddei
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Firenze, Italy
| | | | - Fabrizio Chiti
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Firenze, Italy
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10
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Siltberg-Liberles J, Martinez A. Searching distant homologs of the regulatory ACT domain in phenylalanine hydroxylase. Amino Acids 2008; 36:235-49. [PMID: 18368466 DOI: 10.1007/s00726-008-0057-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Accepted: 03/11/2008] [Indexed: 11/29/2022]
Abstract
High sequence divergence, evolutionary mobility, and superfold topology characterize the ACT domain. Frequently found in multidomain proteins, these domains induce allosteric effects by binding a regulatory ligand usually to an ACT domain dimer interface. In mammalian phenylalanine hydroxylase (PAH), no contacts are formed between ACT domains, and the domain promotes an allosteric effect despite the apparent lack of ligand binding. The increased functional scenario of this abundant domain encouraged us to search for distant homologs, aiming to enhance the understanding of the ACT domain in general and the ACT domain of PAH in particular. The PDB was searched using the FATCAT server with the ACT domain of PAH as a query. The hits that were confirmed by the SSAP algorithm were divided into known ACT domains (KADs) and potential ACT domains (PADs). The FATCAT/SSAP procedure recognized most of the established KADs, as well 18 so far unrecognized non-redundant PADs with extremely low sequence identities and high divergence in functionality and oligomerization. However, analysis of the structural similarity provides remarkable clustering of the proteins according to similarities in ligand binding. Despite enormous sequence divergence and high functional variability, there is a common regulatory theme among these domains. The results reveal the close relationships of the ACT domain of PAH with amino acid binding and metallobinding ACT domains and with acylphosphatase.
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11
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Glutamic acid 219 is critical for the thermostability of a truncated α-amylase from alkaliphilic and thermophilic Bacillus sp. strain TS-23. World J Microbiol Biotechnol 2007. [DOI: 10.1007/s11274-007-9518-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Seitz T, Bocola M, Claren J, Sterner R. Stabilisation of a (betaalpha)8-barrel protein designed from identical half barrels. J Mol Biol 2007; 372:114-29. [PMID: 17631894 DOI: 10.1016/j.jmb.2007.06.036] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 06/05/2007] [Accepted: 06/13/2007] [Indexed: 11/26/2022]
Abstract
It has been suggested that the common (betaalpha)(8)-barrel enzyme fold has evolved by the duplication and fusion of identical (betaalpha)(4)-half barrels, followed by the optimisation of their interface. In our attempts to reconstruct these events in vitro we have previously linked in tandem two copies of the C-terminal half barrel HisF-C of imidazole glycerol phosphate synthase from Thermotoga maritima and subsequently reconstituted in the fusion construct HisF-CC a salt bridge cluster present in wild-type HisF. The resulting recombinant protein HisF-C*C, which was produced in an insoluble form and unfolded with low cooperativity at moderate urea concentrations has now been stabilised and solubilised by a combination of random mutagenesis and selection in vivo. For this purpose, Escherichia coli cells were transformed with a plasmid-based gene library encoding HisF-C*C variants fused to chloramphenicol acetyltransferase (CAT). Stable and soluble variants were identified by the survival of host cells on solid medium containing high concentrations of the antibiotic. The selected HisF-C*C proteins, which were characterised in vitro in the absence of CAT, contained eight different amino acid substitutions. One of the exchanges (Y143C) stabilised HisF-C*C by the formation of an intermolecular disulfide bond. Three of the substitutions (G245R, V248M, L250Q) were located in the long loop connecting the two HisF-C copies, whose subsequent truncation from 13 to 5 residues yielded the stabilised variant HisF-C*C Delta. From the remaining substitutions, Y143H and V234M were most beneficial, and molecular dynamics simulations suggest that they strengthen the interactions between the half barrels by establishing a hydrogen-bonding network and an extensive hydrophobic cluster, respectively. By combining the loop deletion of HisF-C*C Delta with the Y143H and V234M substitutions, the variant HisF-C**C was generated. Recombinant HisF-C**C is produced in soluble form, forms a pure monomer with its tryptophan residues shielded from solvent and unfolds with similar cooperativity as HisF. Our results show that, starting from two identical and fused half barrels, few amino acid exchanges are sufficient to generate a highly stable and compact (betaalpha)(8)-barrel protein with wild-type like structural properties.
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Affiliation(s)
- Tobias Seitz
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
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Miyazono KI, Tsujimura M, Kawarabayasi Y, Tanokura M. Crystal structure of an archaeal homologue of multidrug resistance repressor protein, EmrR, from hyperthermophilic archaea Sulfolobus tokodaii strain 7. Proteins 2007; 67:1138-46. [PMID: 17357153 DOI: 10.1002/prot.21327] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
MarR family proteins, MarR, MexR, and EmrR, are known as bacterial regulators for a phenotype resistant to multiple antibiotic drugs. Genomic data have indicated the presence of bacterial-type transcriptional regulators, including MarR family proteins in archaea, though the archaeal transcription system is close to that of eukaryote. To elucidate the structural basis of the transcriptional regulation mechanism of archaeal MarR family proteins, the crystal structure of the ST1710 protein, which was identified as an archaeal EmrR homologue, StEmrR, from hyperthermophilic archaeon Sulfolobus tokodaii strain 7 was determined at 1.45-A resolution. The protein was composed of two N- and C-terminal dimerization domains, and the DNA-binding domain consisted of a winged helix motif, as in the case of bacterial MarR family proteins. Despite the relatively low overall structural similarity between StEmrR and bacterial MarR family proteins, the structure of the DNA-binding domain displayed high structural similarity. A comparison with the crystal structures of bacterial MarR family proteins revealed that structural variation was mainly due to the different orientation of the two helices at the N- and C-termini. Our results indicated that the distance between the two DNA-binding domains of MarR family proteins would be changed by the rotation of the two terminal helices to interact with the target DNA.
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Affiliation(s)
- Ken-ichi Miyazono
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
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Kim YK, Lee WK, Jin Y, Lee KJ, Jeon H, Yu YG. Doxorubicin Binds to Un-phosphorylated Form of hNopp140 and Reduces Protein Kinase CK2-Dependent Phosphorylation of hNopp140. BMB Rep 2006; 39:774-81. [PMID: 17129415 DOI: 10.5483/bmbrep.2006.39.6.774] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human nucleolar phosphoprotein p140 (hNopp140) is a nucleolar phosphoprotein that can bind to doxorubicin, an anti-cancer agent. We have examined the interaction between hNopp140 and doxorubicin as well as the folding property of hNopp140. Also, the effects of ATP and phosphorylation on the affinity of hNopp140 to doxorubicin are investigated by affinity dependent co-precipitation and surface plasmon resonance methods. Doxorubicin preferentially binds to un-phosphorylated form of hNopp140 with a KD value of 3.3 x 10(-7) M. Furthermore, doxorubicin reduces the protein kinase CK2-dependent phosphorylation of hNopp140, indicating that doxorubicin may perturb the cellular function of hNopp140 by reducing the protein kinase CK2-dependent phosphorylation of hNopp140. Low contents of the secondary structures of hNopp140 and the fast rate of proteolysis imply that hNopp140 has a high percentage of flexible regions or extended loop structures.
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Affiliation(s)
- Yun-Kyoung Kim
- Biomedical Research Center, Korea Institute of Science and Technology, 39-1, Hwawolkok-dong, Songbuk-gu, Seoul 136-791, Korea
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