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Kurian P, Dunston G, Lindesay J. How quantum entanglement in DNA synchronizes double-strand breakage by type II restriction endonucleases. J Theor Biol 2016; 391:102-12. [PMID: 26682627 PMCID: PMC4746125 DOI: 10.1016/j.jtbi.2015.11.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 10/29/2015] [Accepted: 11/15/2015] [Indexed: 10/22/2022]
Abstract
Macroscopic quantum effects in living systems have been studied widely in pursuit of fundamental explanations for biological energy transport and sensing. While it is known that type II endonucleases, the largest class of restriction enzymes, induce DNA double-strand breaks by attacking phosphodiester bonds, the mechanism by which simultaneous cutting is coordinated between the catalytic centers remains unclear. We propose a quantum mechanical model for collective electronic behavior in the DNA helix, where dipole-dipole oscillations are quantized through boundary conditions imposed by the enzyme. Zero-point modes of coherent oscillations would provide the energy required for double-strand breakage. Such quanta may be preserved in the presence of thermal noise by the enzyme's displacement of water surrounding the DNA recognition sequence. The enzyme thus serves as a decoherence shield. Palindromic mirror symmetry of the enzyme-DNA complex should conserve parity, because symmetric bond-breaking ceases when the symmetry of the complex is violated or when physiological parameters are perturbed from optima. Persistent correlations in DNA across longer spatial separations-a possible signature of quantum entanglement-may be explained by such a mechanism.
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Affiliation(s)
- P Kurian
- National Human Genome Center, Howard University College of Medicine, Washington, DC 20059, USA; Department of Physics and Astronomy, Howard University, Washington, DC 20059, USA; Computational Physics Laboratory, Howard University, Washington, DC 20059, USA.
| | - G Dunston
- National Human Genome Center, Howard University College of Medicine, Washington, DC 20059, USA; Department of Microbiology, Howard University College of Medicine, Washington, DC 20059, USA
| | - J Lindesay
- Department of Physics and Astronomy, Howard University, Washington, DC 20059, USA; Computational Physics Laboratory, Howard University, Washington, DC 20059, USA
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2
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Radzikowska E, Baraniak J. Synthesis of PS/PO-chimeric oligonucleotides using mixed oxathiaphospholane and phosphoramidite chemistry. Org Biomol Chem 2015; 13:269-76. [PMID: 25363356 DOI: 10.1039/c4ob01837k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chimeric oligonucleotides containing phosphodiester and phosphorothioate linkages have been obtained using the solid phase synthesis. The oligonucleotide parts possessing natural internucleotide phosphate bonds were assembled using commercially available nucleoside 3'-O-(2-cyanoethyl-N,N-diisopropylamino)phosphoramidites 7 whereas the phosphorothioate segment was built using nucleoside 3'-O-(2-thio-1,3,2-oxathiaphospholanes) 3. The oxidation steps, crucial for the conversion of phosphite linkages into the phosphate moieties, were conducted using tert-butylperoxy-trimethylsilane, and this reagent was not harmful to the diester phosphorothioate linkages. When P-diastereopure nucleoside 3'-O-(2-thio-1,3,2-oxathiaphospholane) monomers were employed the resulting chimeric backbone retained the P-stereoregularity of the phosphorothioate units.
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Affiliation(s)
- Ewa Radzikowska
- Department of Bioorganic Chemistry, Center of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland
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3
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Kaur M, Rob A, Caton-Williams J, Huang Z. Biochemistry of Nucleic Acids Functionalized with Sulfur, Selenium, and Tellurium: Roles of the Single-Atom Substitution. ACTA ACUST UNITED AC 2013. [DOI: 10.1021/bk-2013-1152.ch005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Affiliation(s)
- Manindar Kaur
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303
| | - Abdur Rob
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303
| | | | - Zhen Huang
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303
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4
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Joneja A, Huang X. Linear nicking endonuclease-mediated strand-displacement DNA amplification. Anal Biochem 2011; 414:58-69. [PMID: 21342654 DOI: 10.1016/j.ab.2011.02.025] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 02/17/2011] [Accepted: 02/17/2011] [Indexed: 11/30/2022]
Abstract
We describe a method for linear isothermal DNA amplification using nicking endonuclease-mediated strand displacement by a DNA polymerase. The nicking of one strand of a DNA target by the endonuclease produces a primer for the polymerase to initiate synthesis. As the polymerization proceeds, the downstream strand is displaced into a single-stranded form while the nicking site is also regenerated. The combined continuous repetitive action of nicking by the endonuclease and strand-displacement synthesis by the polymerase results in linear amplification of one strand of the DNA molecule. We demonstrate that DNA templates up to 5000 nucleotides can be linearly amplified using a nicking endonuclease with 7-bp recognition sequence and Sequenase version 2.0 in the presence of single-stranded DNA binding proteins. We also show that a mixture of three templates of 500, 1000, and 5000 nucleotides in length is linearly amplified with the original molar ratios of the templates preserved. Moreover, we demonstrate that a complex library of hydrodynamically sheared genomic DNA from bacteriophage lambda can be amplified linearly.
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Affiliation(s)
- Aric Joneja
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093-0412, USA
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5
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Nawrot B, Rebowska B. DNA oligonucleotides containing stereodefined phosphorothioate linkages in selected positions. ACTA ACUST UNITED AC 2009; Chapter 4:Unit 4.34. [PMID: 19319859 DOI: 10.1002/0471142700.nc0434s36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This unit describes a method for the synthesis of DNA chimeric PO/PS-oligonucleotides with a stereodefined phosphorothioate bond in the selected position. Diastereomerically pure 5'-O-DMTr-N-protected-deoxyribonucleoside-3'-O-(2-thio-spiro-4,4-pentamethylene-1,3,2-oxathiaphospholane)s obtained according to the previously described protocol (UNIT 4.17) are transformed via a stereospecific 1,3,2-oxathiaphospholane-ring opening condensation into the corresponding dinucleoside phosphorothioates. Such dimers cannot be introduced into an oligonucleotide chain via the phosphoramidite approach since the unprotected P-S(-) bond is easily oxidized during routine I(2)/Py/water oxidation of the phosphite function. In the methodology described here, the reversible alkylation of the PS function is applied. Subsequently, the 3'-phosphoramidites of such PS-protected dimers prepared in situ are used for routine synthesis of chimeric PO/PS-oligonucleotides according to the phosphoramidite method. The presence of the alkylated PS-function requires modified conditions for oligonucleotide deprotection and cleavage from the solid support. Detailed procedures for the synthesis of PS-dimers and their incorporation into an oligonucleotide chain, as well as deprotection/purification steps are presented.
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Affiliation(s)
- Barbara Nawrot
- Department of Bioorganic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lodz, Poland
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6
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Significance of stereochemistry of 3'-terminal phosphorothioate-modified primer in DNA polymerase-mediated chain extension. Mol Biotechnol 2008; 40:119-26. [PMID: 18769882 DOI: 10.1007/s12033-008-9096-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Accepted: 03/20/2008] [Indexed: 10/21/2022]
Abstract
Influence of stereochemistry of the 3'-terminal phosphorothioate (PS)-modified primers was studied in a single base extension (SBE) assay to evaluate any improvements in specificity. SBE reactions were catalyzed by members of the high fidelity Pfu family of DNA polymerases with (exo+) or without (exo-) 3' --> 5' exonucleolytic activity. The diastereomerically pure PS-labeled primers used in these studies were obtained either by the stereospecific chemical synthesis invented in our laboratory or by the more conventional ion-exchange chromatographic method for separation of a mixture of diastereomers (R(P) and S(P)). When the SBE reaction was performed in the presence of mispaired 2'-deoxyribonucleoside triphosphates (dNTPs), the "racemic" 3'-phosphorothioate primer mixture resulted in a lower level of 3' --> 5' exonuclease-mediated cleavage products in comparison to the SBE reactions carried out with the corresponding unmodified primer. When the diastereomerically pure RP 3'-phosphorothioate primer was examined, the results were largely the same as for the racemic 3'-phosphorothioate primer mixture. In contrast, a 3'-PS primer of S(P) configuration displayed significantly improved performance in the SBE reaction. This included the lack of 3' --> 5' proofreading products, less mispriming, and improved yield of incorporation of the correct nucleotide.
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7
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Stivers JT, Nagarajan R. Probing enzyme phosphoester interactions by combining mutagenesis and chemical modification of phosphate ester oxygens. Chem Rev 2007; 106:3443-67. [PMID: 16895336 PMCID: PMC2729714 DOI: 10.1021/cr050317n] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- James T Stivers
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, Maryland 21205, USA.
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8
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Karwowski B, Guga P, Kobylariska A, Stec WJ. Nucleoside 3′-O-(2-Oxo-“Spiro”-4.4-Pentamethylene-1.3.2-Oxathiaphospholane)S: Monomers For Stereocontrolled Synthesis Of Oligo(Nucleoside Phosphorothioate/Phosphate)S. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/07328319808004710] [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]
Affiliation(s)
- Boleslaw Karwowski
- a Polish Academy of Sciences, Centre of Molecular and Macromolecular Studies, Department of Bioorganic Chemistry , Sienkiewicza 112, 90-363 , Lódź , Poland
| | - Piotr Guga
- a Polish Academy of Sciences, Centre of Molecular and Macromolecular Studies, Department of Bioorganic Chemistry , Sienkiewicza 112, 90-363 , Lódź , Poland
| | - Anna Kobylariska
- a Polish Academy of Sciences, Centre of Molecular and Macromolecular Studies, Department of Bioorganic Chemistry , Sienkiewicza 112, 90-363 , Lódź , Poland
| | - Wojciech J. Stec
- a Polish Academy of Sciences, Centre of Molecular and Macromolecular Studies, Department of Bioorganic Chemistry , Sienkiewicza 112, 90-363 , Lódź , Poland
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9
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Abstract
We determined the genomic structure of the gene encoding human DNA methyltransferase (DNA MTase). Six overlapping human genomic DNA clones which include all of the known cDNA sequence were isolated. Analysis of these clones demonstrates that the human DNA MTase gene consists of at least 40 exons and 39 introns spanning a distance of 60 kilobases. Elucidation of the chromosomal organization of the human DNA MTase gene provides the template for future structure-function analysis of the properties of mammalian DNA MTase.
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Affiliation(s)
- S Ramchandani
- Department of Pharmacology and Therapeutics, McGill University, Montreal, PQ, Canada
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10
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Stein CA. How to design an antisense oligodeoxynucleotide experiment: a consensus approach. ANTISENSE & NUCLEIC ACID DRUG DEVELOPMENT 1998; 8:129-32. [PMID: 9593051 DOI: 10.1089/oli.1.1998.8.129] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- C A Stein
- Department of Medicine, Columbia University, New York, NY 10032, USA
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11
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Thorogood H, Grasby JA, Connolly BA. Influence of the phosphate backbone on the recognition and hydrolysis of DNA by the EcoRV restriction endonuclease. A study using oligodeoxynucleotide phosphorothioates. J Biol Chem 1996; 271:8855-62. [PMID: 8621526 DOI: 10.1074/jbc.271.15.8855] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
A set of phosphorothioate-containing oligonucleotides based on pGACGATATCGTC, a self-complementary dodecamer that contains the EcoRV recognition sequence (GATATC), has been prepared. The phosphorothioate group has been individually introduced at the central nine phosphate positions and the two diastereomers produced at each site separated and purified. The Km and Vmax values found for each of these modified DNA molecules with the EcoRV restriction endonuclease have been determined and compared with those seen for the unmodified all-phosphate-containing dodecamer. This has enabled an evaluation of the roles that both of the non-esterified oxygen atoms in the individual phosphates play in DNA binding and hydrolysis by the endonuclease. The results have also been compared with crystal structures of the EcoRV endonuclease, complexed with an oligodeoxynucleotide, to allow further definition of phosphate group function during substrate binding and turnover. For further study, see the related article "Probing the Indirect Readout of the Restriction Enzyme EcoRV: Mutational Analysis of Contacts to the DNA Backbone" (Wenz, A., Jeltsch, A., and Pingoud, A. (1996) J. Biol. Chem. 271, 5565-5573).
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Affiliation(s)
- H Thorogood
- Department of Biochemistry and Genetics, University of Newcastle, Newcastle upon Tyne NE2 4HH, United Kingdom
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12
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Zhang ZY, Dixon JE. Active site labeling of the Yersinia protein tyrosine phosphatase: the determination of the pKa of the active site cysteine and the function of the conserved histidine 402. Biochemistry 1993; 32:9340-5. [PMID: 8369304 DOI: 10.1021/bi00087a012] [Citation(s) in RCA: 203] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In this report, we demonstrated that the Yersinia protein tyrosine phosphatase (PTPase) could be inactivated by the alkylating agent iodoacetate. The enzyme modification was selective, and the covalent attachment was stoichiometric. The residue that was labeled by iodoacetate was shown to be Cys403, which was the same catalytically essential residue identified by site-directed mutagenesis [Guan, K. L., & Dixon, J.E. (1990) Science 249, 553-556]. The rate of iodoacetate modification decreased as the ionic strength of the media increased. There was no significant D2O solvent isotope effect associated with the inactivation of the enzyme, suggesting that thiol anion of Cys403 reacted as a nucleophile. The Yersinia PTPase also displayed differential reactivity (940-fold) toward iodoacetate over iodoacetamide. This indicates that residues within the active site of the enzyme are positively charged. The pKa of the active site thiol group was determined to be 4.67. The low pKa value suggests that ionic interactions are important in stabilizing the thiolate anion. One candidate residue for this stabilization is the invariant histidine (His402) found in all PTPases. Substitutions of His402 with Asn or Ala altered the active site thiol pKa to 5.99 and 7.35, respectively. Interestingly, the active site thiol in the mutants also showed enhanced reactivity toward iodoacetate. The second-order rate constants for the inactivation of the wild-type enzyme, H402N, and H402A were 59.7, 3305, and 1763 M-1 min-1, respectively.
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Affiliation(s)
- Z Y Zhang
- Department of Biological Chemistry, University of Michigan, Ann Arbor 48109-0606
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13
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Olsen DB, Sayers JR, Eckstein F. Site-directed mutagenesis of single-stranded and double-stranded DNA by phosphorothioate approach. Methods Enzymol 1993; 217:189-217. [PMID: 8386289 DOI: 10.1016/0076-6879(93)17063-b] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- D B Olsen
- Merck Sharp and Dohme, Research Laboratories, West Point, Pennsylvania 19486
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14
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Hosaka H, Nakamura H, Funakoshi H, Takaku H. Nucleoside Phosphite, O-Bis(1,1,1,3,3,3-hexafluoro-2-propyl) Deoxyribonucleosid-3′-yl Phosphites. A Versatile Synthetic Intermediate for Phosphonate Modified Nucleotide and Oligonucleotide Synthesis. CHEM LETT 1992. [DOI: 10.1246/cl.1992.935] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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15
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Steczko J, Donoho GP, Clemens JC, Dixon JE, Axelrod B. Conserved histidine residues in soybean lipoxygenase: functional consequences of their replacement. Biochemistry 1992; 31:4053-7. [PMID: 1567851 DOI: 10.1021/bi00131a022] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Sequences of 13 lipoxygenases from various plant and mammalian species, thus far reported, display a motif of 38 amino acid residues which includes 5 conserved histidines and a 6th histidine about 160 residues downstream. These residues occur at positions 494, 499, 504, 522, 531, and 690 in soybean lipoxygenase isozyme L-1. Since the participation of iron in the lipoxygenase reaction has been established and existing evidence based on Mössbauer and EXAFS spectroscopy suggests that histidines may be involved in iron binding, the effect of the above residues has been examined in soybean lipoxygenase L-1. Six singly mutated lipoxygenases have been produced in which each of the His residues has been replaced with glutamine. Two additional mutants have been constructed wherein the codons for His-494 and His-504 have been replaced by serine codons. All of the mutant lipoxygenases, which were obtained by expression in Escherichia coli, have mobilities identical to that of the wild-type enzyme on denaturing gel electrophoresis and respond to lipoxygenase antibodies. The mutated proteins H499Q, H504Q, H504S, and H690Q are virtually inactive, while H522Q has about 1% of the wild-type activity. H494Q, H494S, and H531Q are about 37%, 8%, and 20% as active as the wild type, respectively. His-517 is conserved in the several lipoxygenase isozymes but not in the animal isozymes. The mutant H517Q has about 33% of the wild-type activity. The inactive mutants, H499Q, H504Q, H504S, and H690Q, become insoluble when heated for 3 min at 65 degrees C, as does H522Q. The other mutants and the wild-type are stable under these conditions.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Steczko
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907-1153
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16
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Dahl O. Preparation of Nucleoside Phosphorothioates, Phosphorodithioates and Related Compounds. ACTA ACUST UNITED AC 1991. [DOI: 10.1080/01961779108048765] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Steczko J, Donoho GA, Dixon JE, Sugimoto T, Axelrod B. Effect of ethanol and low-temperature culture on expression of soybean lipoxygenase L-1 in Escherichia coli. Protein Expr Purif 1991; 2:221-7. [PMID: 1821792 DOI: 10.1016/1046-5928(91)90075-t] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have constructed a full-length cDNA that encodes soybean seed lipoxygenase L-1 and have expressed it in Escherichia coli. This gene was inserted into a pT7-7 expression vector, containing the T7 RNA polymerase promoter. E. coli, strain BL21 (DE3), which carries the T7 promoter in its genome, was transfected with the plasmid. Expression of this gene when the cells were cultured at 37 degrees C yielded polypeptide that was recognized by anti-L-1 antibody, but had very little lipoxygenase activity. Yields of active enzyme were markedly increased when cells were cultured at 15-20 degrees C. When ethanol, which has been reported to be an excellent elicitor of heat-shock proteins in E. coli, was also present at a level of 3% the yield was further increased by 40%. Under optimum conditions 22-30 mg of soluble active enzyme was obtained per liter of culture.
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Affiliation(s)
- J Steczko
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907-1153
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18
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Olsen D, Kotzorek G, Sayers J, Eckstein F. Inhibition of the restriction endonuclease BanII using modified DNA substrates. Determination of phosphate residues critical for the formation of an active enzyme-DNA complex. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(18)77314-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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19
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Bennett SP, Halford SE. Recognition of DNA by type II restriction enzymes. CURRENT TOPICS IN CELLULAR REGULATION 1989; 30:57-104. [PMID: 2695290 DOI: 10.1016/b978-0-12-152830-0.50005-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- S P Bennett
- Department of Biochemistry, School of Medical Sciences, University of Bristol, England
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22
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Fujii M, Ozaki K, Kume A, Sekine M, Hata T. Acylphosphonates. 6. Reaction mechanism of Zn/Me3SiCl mediated conversion of 2,2,2-trichloroethoxycarbonylphosphonates to silyl phosphites. Tetrahedron Lett 1986. [DOI: 10.1016/s0040-4039(00)84797-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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23
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Acylphosphonates. 5. 1A new method for stereospecific generation of phosphorothioate via aroylphosphonate intermediate. Tetrahedron Lett 1986. [DOI: 10.1016/s0040-4039(00)84142-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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Froehler BC. Deoxynucleoside H-Phosphonate diester intermediates in the synthesis of internucleotide phosphate analogues. Tetrahedron Lett 1986. [DOI: 10.1016/s0040-4039(00)85269-7] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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25
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Relaxation of supercoiled phosphorothioate DNA by mammalian topoisomerases is inhibited in a base-specific manner. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(18)89292-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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