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The Facts and Family Secrets of Plasmids That Replicate via the Rolling-Circle Mechanism. Microbiol Mol Biol Rev 2021; 86:e0022220. [PMID: 34878299 DOI: 10.1128/mmbr.00222-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Plasmids are self-replicative DNA elements that are transferred between bacteria. Plasmids encode not only antibiotic resistance genes but also adaptive genes that allow their hosts to colonize new niches. Plasmid transfer is achieved by conjugation (or mobilization), phage-mediated transduction, and natural transformation. Thousands of plasmids use the rolling-circle mechanism for their propagation (RCR plasmids). They are ubiquitous, have a high copy number, exhibit a broad host range, and often can be mobilized among bacterial species. Based upon the replicon, RCR plasmids have been grouped into several families, the best known of them being pC194 and pUB110 (Rep_1 family), pMV158 and pE194 (Rep_2 family), and pT181 and pC221 (Rep_trans family). Genetic traits of RCR plasmids are analyzed concerning (i) replication mediated by a DNA-relaxing initiator protein and its interactions with the cognate DNA origin, (ii) lagging-strand origins of replication, (iii) antibiotic resistance genes, (iv) mobilization functions, (v) replication control, performed by proteins and/or antisense RNAs, and (vi) the participating host-encoded functions. The mobilization functions include a relaxase initiator of transfer (Mob), an origin of transfer, and one or two small auxiliary proteins. There is a family of relaxases, the MOBV family represented by plasmid pMV158, which has been revisited and updated. Family secrets, like a putative open reading frame of unknown function, are reported. We conclude that basic research on RCR plasmids is of importance, and our perspectives contemplate the concept of One Earth because we should incorporate bacteria into our daily life by diminishing their virulence and, at the same time, respecting their genetic diversity.
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Kunkel F, Lurz R, Weinhold E. A 7-Deazaadenosylaziridine Cofactor for Sequence-Specific Labeling of DNA by the DNA Cytosine-C5 Methyltransferase M.HhaI. Molecules 2015; 20:20805-22. [PMID: 26610450 PMCID: PMC6332214 DOI: 10.3390/molecules201119723] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 11/03/2015] [Accepted: 11/10/2015] [Indexed: 12/30/2022] Open
Abstract
DNA methyltransferases (MTases) catalyze the transfer of the activated methyl group of the cofactor S-adenosyl-l-methionine (AdoMet or SAM) to the exocyclic amino groups of adenine or cytosine or the C5 ring atom of cytosine within specific DNA sequences. The DNA adenine-N6 MTase from Thermus aquaticus (M.TaqI) is also capable of coupling synthetic N-adenosylaziridine cofactor analogues to its target adenine within the double-stranded 5′-TCGA-3′ sequence. This M.TaqI-mediated coupling reaction was exploited to sequence-specifically deliver fluorophores and biotin to DNA using N-adenosylaziridine derivatives carrying reporter groups at the 8-position of the adenine ring. However, these 8-modified aziridine cofactors were poor substrates for the DNA cytosine-C5 MTase from Haemophilus haemolyticus (M.HhaI). Based on the crystal structure of M.HhaI in complex with a duplex oligodeoxynucleotide and the cofactor product, we synthesized a stable 7-deazaadenosylaziridine derivative with a biotin group attached to the 7-position via a flexible linker. This 7-modified aziridine cofactor can be efficiently used by M.HhaI for the direct, quantitative and sequence-specific delivery of biotin to the second cytosine within 5′-GCGC-3′ sequences in short duplex oligodeoxynucleotides and plasmid DNA. In addition, we demonstrate that biotinylation by M.HhaI depends on the methylation status of the target cytosine and, thus, could provide a method for cytosine-C5 DNA methylation detection in mammalian DNA.
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Affiliation(s)
- Falk Kunkel
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, Aachen D-52056, Germany.
| | - Rudi Lurz
- Max-Planck-Institute for Molecular Genetics, Ihnestrasse 73, Berlin D-14195, Germany.
| | - Elmar Weinhold
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, Aachen D-52056, Germany.
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3
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Pljevaljcić G, Schmidt F, Scheidig AJ, Lurz R, Weinhold E. Quantitative Labeling of Long Plasmid DNA with Nanometer Precision. Chembiochem 2007; 8:1516-9. [PMID: 17654629 DOI: 10.1002/cbic.200700294] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Goran Pljevaljcić
- Present address: Department of Molecular Biology, MB19, The Scripps Research Institute, 10550 N. Torrey Pines Rd. La Jolla, CA 92037, USA
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Costa M, Solà M, del Solar G, Eritja R, Hernández-Arriaga AM, Espinosa M, Gomis-Rüth FX, Coll M. Plasmid transcriptional repressor CopG oligomerises to render helical superstructures unbound and in complexes with oligonucleotides. J Mol Biol 2001; 310:403-17. [PMID: 11428897 DOI: 10.1006/jmbi.2001.4760] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
CopG is a 45 amino acid residue transcriptional repressor involved in the copy number control of the streptococcal plasmid pMV158. To do so, it binds to a DNA operator that contains a 13 bp pseudosymmetric DNA element. Binding of CopG to its operator results in repression, at the transcriptional level, of its own synthesis and that of the initiator of replication protein, RepB. Biochemical experiments have shown that CopG co-operatively associates to its target DNA at low protein:DNA ratios, completely protecting four helical turns on the same face of the double helix in both directions from the inverted repeat that constitutes the CopG primary target. This has been correlated with a CopG-mediated DNA bend of about 100 degrees. Here, we show that binding of CopG to DNA fragments containing the inverted repeat just at one end led to nucleation of the protein initiating from the inverted repeat. Nucleation extended to the entire fragment, with CopG-DNA contacts occurring on the same face of the DNA helix. The protein, the prototype for a family of homologous plasmid repressors, displays a homodimeric ribbon-helix-helix arrangement. It polymerises within the unbound crystal to render a continuous right-handed protein superhelix of homodimers, around which a bound double-stranded (ds) DNA could wrap. We have solved the crystal structure of CopG in complex with a 22 bp dsDNA oligonucleotide encompassing the cognate pseudosymmetric element. In the crystal, one protein tetramer binds at one face of the DNA with two parallel beta-ribbons inserted into the major groove. The DNA is bent about 50 degrees under compression of both major and minor grooves. A continuous right-handed complex helix made up mainly by protein-protein and some protein-DNA interactions is observed. The protein-protein interactions involve regions similar to those observed in the oligomerisation of the native crystals and those employed to set up the functional tetramer. A previously solved complex structure of the protein with a 19 bp dsDNA had unveiled a left-handed helical superstructure just made up by DNA interactions.
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Affiliation(s)
- M Costa
- Institut de Biologia Molecular de Barcelona, CID-CSIC, Jordi Girona, 18-26, Barcelona, 08034, Spain
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5
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Jakimowicz D, Majkadagger J, Konopa G, Wegrzyn G, Messer W, Schrempf H, Zakrzewska-Czerwińska J. Architecture of the Streptomyces lividans DnaA protein-replication origin complexes. J Mol Biol 2000; 298:351-64. [PMID: 10772855 DOI: 10.1006/jmbi.2000.3686] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Streptomyces oriC region contains two clusters of 19 DnaA boxes separated by a spacer (134 bp). The Streptomyces DnaA protein consists, like all other DnaA proteins, of four domains: domain III and the carboxyterminal part (domain IV) are responsible for binding of ATP and DNA, respectively. Binding of the DnaA protein to the entire oriC region analysed by electron microscopy showed that the DnaA protein forms separate complexes at each of the clusters of DnaA boxes, but not at the spacer separating them. In vivo mutational analysis revealed that the number of DnaA boxes and the presence of the spacer linking both groups of DnaA boxes seem to be important for a functional Streptomyces origin. We suggest that the arrangement of DnaA boxes allows the DNA-bound DnaA protein to induce bending and looping of the oriC region. As it was shown by electrophoretic mobility shift assay and "one hybrid system", two domains, I and III, facilitate interactions between DnaA molecules. We postulate that domain I and domain III could be involved in cooperativity at distant and at closely spaced DnaA boxes, respectively. The long domain II extends the range over which N termini (domain I) of DNA-bound DnaA protein can form dimers. Thus, interactions between DnaA molecules may bring two clusters of DnaA boxes separated by the spacer into functional contact by loop formation. Removal of the spacer region or deletion of domains I and II resulted, respectively, in nucleoprotein complexes which are not fully developed, or huge nucleoprotein aggregates.
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MESH Headings
- Allosteric Site
- Bacterial Proteins/chemistry
- Bacterial Proteins/genetics
- Bacterial Proteins/metabolism
- Bacterial Proteins/ultrastructure
- Chromosomes, Bacterial/chemistry
- Chromosomes, Bacterial/genetics
- Chromosomes, Bacterial/metabolism
- Chromosomes, Bacterial/ultrastructure
- Computer Simulation
- DNA Ligases/metabolism
- DNA Replication/genetics
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Bacterial/metabolism
- DNA, Bacterial/ultrastructure
- DNA, Circular/chemistry
- DNA, Circular/genetics
- DNA, Circular/metabolism
- DNA-Binding Proteins/chemistry
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- DNA-Binding Proteins/ultrastructure
- Dimerization
- Kinetics
- Microscopy, Electron
- Models, Biological
- Mutation/genetics
- Nucleic Acid Conformation
- Protein Binding
- Protein Structure, Tertiary
- Replication Origin/genetics
- Streptomyces/chemistry
- Streptomyces/genetics
- Transformation, Bacterial/genetics
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Affiliation(s)
- D Jakimowicz
- Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. Weigla 12, Wroclaw, 53-114, Poland
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6
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Jensen RB, Lurz R, Gerdes K. Mechanism of DNA segregation in prokaryotes: replicon pairing by parC of plasmid R1. Proc Natl Acad Sci U S A 1998; 95:8550-5. [PMID: 9671715 PMCID: PMC21113 DOI: 10.1073/pnas.95.15.8550] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Prokaryotic chromosomes and plasmids encode partitioning systems that are required for DNA segregation at cell division. The systems are thought to be functionally analogous to eukaryotic centromeres and to play a general role in DNA segregation. The parA system of plasmid R1 encodes two proteins ParM and ParR, and a cis-acting centromere-like site denoted parC. The ParR protein binds to parC in vivo and in vitro. The ParM protein is an ATPase that interacts with ParR specifically bound to parC. Using electron microscopy, we show here that parC mediates efficient pairing of plasmid molecules. The pairing requires binding of ParR to parC and is stimulated by the ParM ATPase. The ParM mediated stimulation of plasmid pairing is dependent on ATP hydrolysis by ParM. Using a ligation kinetics assay, we find that ParR stimulates ligation of parC-containing DNA fragments. The rate-of-ligation was increased by wild type ParM protein but not by mutant ParM protein deficient in the ATPase activity. Thus, two independent assays show that parC mediates pairing of plasmid molecules in vitro. These results are consistent with the proposal that replicon pairing is part of the mechanism of DNA segregation in prokaryotes.
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Affiliation(s)
- R B Jensen
- Department of Molecular Biology, Odense University, Campusvej 55, DK-5230 Odense M, Denmark
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7
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Gomis-Rüth FX, Solà M, Pérez-Luque R, Acebo P, Alda MT, González A, Espinosa M, del Solar G, Coll M. Overexpression, purification, crystallization and preliminary X-ray diffraction analysis of the pMV158-encoded plasmid transcriptional repressor protein CopG. FEBS Lett 1998; 425:161-5. [PMID: 9541028 DOI: 10.1016/s0014-5793(98)00219-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Plasmid pMV158 encodes a 45 amino acid transcriptional repressor, CopG, which is involved in copy number control. A new procedure for overproduction and purification of the protein has been developed. The CopG protein thus obtained retained its ability to specifically bind to DNA and to repress its own promoter. Purified CopG protein has been crystallized using the sitting-drop vapor diffusion method. The crystals, belonging to orthorhombic space group C222(1) (cell constants a = 67.2 A, b = 102.5 A, c = 40.2 A), were obtained from a solution containing methylpentanediol, benzamidine and sodium chloride, buffered to pH 6.7. Complete diffraction data up to 1.6 A resolution have been collected. Considerations about the Matthews parameter account for the most likely presence of three molecules in the asymmetric unit (2.27 A3/Da).
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Affiliation(s)
- F X Gomis-Rüth
- Centre d'Investigació i Desenvolupament, C.S.I.C., Barcelona, Spain.
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8
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Krause M, Rückert B, Lurz R, Messer W. Complexes at the replication origin of Bacillus subtilis with homologous and heterologous DnaA protein. J Mol Biol 1997; 274:365-80. [PMID: 9405146 DOI: 10.1006/jmbi.1997.1404] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The initial steps in the formation of the initiation complex at oriC of Bacillus subtilis were analyzed with special emphasis on the exchangeability of B. subtilis DnaA protein by DnaA of Escherichia coli. The DNA binding domain of B. subtilis DnaA protein was localized in the 93 C-terminal amino acids. Formation of the "initial complex", as analyzed by electron microscopy, was indistinguishable with B. subtilis DnaA protein or with E. coli DnaA. Similarly, both proteins were able to form loops by interaction of DnaA proteins bound to the DnaA box regions upstream and downstream of the dnaA gene in B. subtilis oriC. The region of local unwinding in the "open complex" was precisely defined. It is located at one side of a region of helical instability, a DNA unwinding element (DUE). Unwinding in oriC could only be catalyzed by the homologous DnaA protein.
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Affiliation(s)
- M Krause
- Max-Planck-Institut für molekulare Genetik, Berlin-Dahlem, Germany
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9
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Abstract
This review attempts to substantiate the notion that nonlinear DNA structures allow prokaryotic cells to evolve complex signal integration devices that, to some extent, parallel the transduction cascades employed by higher organisms to control cell growth and differentiation. Regulatory cascades allow the possibility of inserting additional checks, either positive or negative, in every step of the process. In this context, the major consequence of DNA bending in transcription is that promoter geometry becomes a key regulatory element. By using DNA bending, bacteria afford multiple metabolic control levels simply through alteration of promoter architecture, so that positive signals favor an optimal constellation of protein-protein and protein-DNA contacts required for activation. Additional effects of regulated DNA bending in prokaryotic promoters include the amplification and translation of small physiological signals into major transcriptional responses and the control of promoter specificity for cognate regulators.
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Affiliation(s)
- J Pérez-Martín
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Campus de Cantoblanco, Madrid, Spain
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10
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Ziegelin G, Calendar R, Lurz R, Lanka E. The helicase domain of phage P4 alpha protein overlaps the specific DNA binding domain. J Bacteriol 1997; 179:4087-95. [PMID: 9209020 PMCID: PMC179226 DOI: 10.1128/jb.179.13.4087-4095.1997] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Replication initiation depends on origin recognition, helicase, and primase activities. In phage P4, a second DNA region, the cis replication region (crr), is also required for replication initiation. The multifunctional alpha protein of phage P4, which is essential for DNA replication, combines the three aforementioned activities on a single polypeptide chain. Protein domains responsible for the activities were identified by mutagenesis. We show that mutations of residues G506 and K507 are defective in vivo in phage propagation and in unwinding of a forked helicase substrate. This finding indicates that the proposed P loop is essential for helicase activity. Truncations of gene product alpha (gp alpha) demonstrated that 142 residues of the C terminus are sufficient for specifically binding ori and crr DNA. The minimal binding domain retains gp alpha's ability to induce loop formation between ori and crr. In vitro and in vivo analysis of short C-terminal truncations indicate that the C terminus is needed for helicase activity as well as for specific DNA binding.
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Affiliation(s)
- G Ziegelin
- Max-Planck-Institut für Molekulare Genetik, Berlin, Germany
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11
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Abstract
Replication of satellite phage P4 of Escherichia coli is dependent on three phage-encoded elements: the origin (ori), a cis replication element (crr), and the product of the alpha gene, gp alpha. In P4 replication is origin-specific resulting in monomeric form I DNA. DNA synthesis requires chromosomally encoded proteins DNA polymerase III holoenzyme, SSB, DNA gyrase and probably topoisomerase I; host-encoded initiation and priming functions are dispensable. The alpha protein is multifunctional in P4 replication, combining three activities in a single polypeptide chain. First, the protein complexes specifically with type I repeats at ori and crr. Second, the helicase activity associated with gp alpha unwinds DNA with 3'--> 5' polarity. Third, the primase activity results in the synthesis of RNA primers. Defined sequence motifs in gp alpha correlate with the helicase and primase activities which are arranged in distinct, separable domains. Primase activity is associated with the N-terminal half of the protein, ori/crr binding with the C-terminal portion. A model for the initiation mechanism of P4 replication which resembles that of mammalian simian virus 40 is discussed.
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Affiliation(s)
- G Ziegelin
- Max-Planck-Institut für Molekulare Genetik, Abteilung Schuster, Berlin, Germany
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12
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Heinzel T, Lurz R, Dobrinski B, Velleman M, Schuster H. C1 repressor-mediated DNA looping is involved in C1 autoregulation of bacteriophage P1. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)31778-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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13
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Filutowicz M, Dellis S, Levchenko I, Urh M, Wu F, York D. Regulation of replication of an iteron-containing DNA molecule. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1994; 48:239-73. [PMID: 7938550 DOI: 10.1016/s0079-6603(08)60857-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- M Filutowicz
- Department of Bacteriology, University of Wisconsin-Madison 53706
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14
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Abstract
The question of whether protein-induced DNA bending can act as a switch factor when placed upstream of an array of promoters located in tandem was investigated in vivo. The catabolite activating protein binding site of the fur operon was replaced by the binding site of the RepA repressor protein, which is able to bend DNA immediately after binding. Appropriately phased induced bending could act as a transcriptional switch factor in vivo.
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Affiliation(s)
- J Pérez-Martín
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientifícas, Madrid, Spain
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15
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King I, de Soyza T, Catanzaro D, Lavin T. Thyroid hormone receptor-induced bending of specific DNA sequences is modified by an accessory factor. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)54178-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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16
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Ziegelin G, Pansegrau W, Lurz R, Lanka E. TraK protein of conjugative plasmid RP4 forms a specialized nucleoprotein complex with the transfer origin. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)41923-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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17
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Laible G, Keck W, Lurz R, Mottl H, Frère JM, Jamin M, Hakenbeck R. Penicillin-binding protein 2x of Streptococcus pneumoniae. Expression in Escherichia coli and purification of a soluble enzymatically active derivative. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 207:943-9. [PMID: 1499568 DOI: 10.1111/j.1432-1033.1992.tb17128.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A 2.5-kb DNA fragment including the structural gene coding for the penicillin-binding protein 2x (PBP 2x) of Streptococcus pneumoniae has been cloned into the vector pJDC9 and expressed in Escherichia coli. Mapping of RNA polymerase binding sites by electron microscopy indicated that the pbpX promoter is well recognized by the E. coli enzyme. However, high-level expression occurred mainly under the control of the lac promoter upstream of the pJDC9 multiple cloning site. After induction with isopropyl beta-d-thiogalactopyranoside, PBP 2x was expressed as one of the major cellular proteins. PBP 2x produced in E. coli corresponded to the pneumococcal PBP 2x in terms of electrophoretic mobility, fractionation with the cytoplasmic membrane, and penicillin-binding capacity. Deletion of 30 hydrophobic N-terminal amino acid residues at positions 19-48 resulted in high-level expression of a cytoplasmic, soluble PBP 2x derivative (PBP 2x*) which still retained full beta-lactam-binding activity. A two-step procedure involving dye affinity chromatography was established for obtaining large amounts of highly purified enzymatically active PBP 2x*.
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Affiliation(s)
- G Laible
- Max-Planck Institut für molekulare Genetik, Berlin, Federal Republic of Germany
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18
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Pérez-Martín J, Espinosa M. A genetic system to study the in vivo role of transcriptional regulators in Escherichia coli. Gene X 1992; 116:75-80. [PMID: 1628847 DOI: 10.1016/0378-1119(92)90631-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
A genetic system for studying in vivo the interactions between a transcriptional regulatory protein and its target DNA has been developed for Escherichia coli. It is composed of two compatible plasmids: one high-copy-number promoter-probe vector, and one low-copy-number vector in which the gene encoding the desired protein is cloned under the control of an inducible promoter. The system was successfully tested for its specificity and for dosage analysis by using a combination of the plasmid pLS1-encoded RepA repressor and its target DNA.
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Affiliation(s)
- J Pérez-Martín
- Centro de Investigaciones Biologicas, CSIC, Madrid, Spain
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19
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Plasmid pLS1-encoded RepA protein regulates transcription from repAB promoter by binding to a DNA sequence containing a 13-base pair symmetric element. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)38382-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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