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Cook A, Hari-Gupta Y, Toseland CP. Application of the SSB biosensor to study in vitro transcription. Biochem Biophys Res Commun 2018; 496:820-825. [PMID: 29378185 PMCID: PMC5811048 DOI: 10.1016/j.bbrc.2018.01.147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 01/24/2018] [Indexed: 01/09/2023]
Abstract
Gene expression, catalysed by RNA polymerases (RNAP), is one of the most fundamental processes in living cells. The majority of methods to quantify mRNA are based upon purification of the nucleic acid which leads to experimental inaccuracies and loss of product, or use of high cost dyes and sensitive spectrophotometers. Here, we describe the use of a fluorescent biosensor based upon the single stranded binding (SSB) protein. In this study, the SSB biosensor showed similar binding properties to mRNA, to that of its native substrate, single-stranded DNA (ssDNA). We found the biosensor to be reproducible with no associated loss of product through purification, or the requirement for expensive dyes. Therefore, we propose that the SSB biosensor is a useful tool for comparative measurement of mRNA yield following in vitro transcription. Single-stranded binding protein can bind mRNA similar to single-stranded DNA. The biosensor MDCC-SSB can be used to quantify mRNA yield from in vitro transcription. Myosin VI motor activity is required for in vitro and in vivo transcription.
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Affiliation(s)
- Alexander Cook
- School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK
| | - Yukti Hari-Gupta
- School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK
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2
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Kirti A, Kumar A, Rajaram H. Differential regulation of ssb genes in the nitrogen-fixing cyanobacterium, Anabaena sp. strain PCC7120 1. JOURNAL OF PHYCOLOGY 2017; 53:322-332. [PMID: 28000228 DOI: 10.1111/jpy.12500] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 09/23/2016] [Indexed: 06/06/2023]
Abstract
Anabaena sp. PCC7120 possesses three genes coding for single-stranded DNA-binding (SSB) protein, of which ssb1 was a single gene, and ssb2 and ssb3 are the first genes of their corresponding operons. Regulation of the truncated ssb genes, ssb1 (alr0088) and ssb2 (alr7559), was unaffected by N-status of growth. They were negatively regulated by the SOS-response regulatory protein LexA, as indicated by the (i) binding of Anabaena LexA to the LexA box of regulatory regions of ssb1 and ssb2, and (ii) decreased expression of the downstream gfp reporter gene in Escherichia coli upon co-expression of LexA. However, the full-length ssb gene, ssb3 (all4779), was regulated by the availability of Fe2+ and combined nitrogen, as indicated by (i) increase in the levels of SSB3 protein on Fe2+ -depletion and decrease under Fe2+ -excess conditions, and (ii) 1.5- to 1.6-fold decrease in activity under nitrogen-fixing conditions compared to nitrogen-supplemented conditions. The requirement of Fe2+ as a co-factor for repression by FurA and the increase in levels of FurA under nitrogen-deficient conditions in Anabaena (Lopez-Gomollon et al. 2007) indicated a possible regulation of ssb3 by FurA. This was substantiated by (i) the binding of FurA to the regulatory region of ssb3, (ii) repression of the expression of the downstream gfp reporter gene in E. coli upon co-expression of FurA, and (iii) negative regulation of ssb3 promoter activity by the upstream AT-rich region in Anabaena. This is the first report on possible role of FurA, an important protein for iron homeostasis, in DNA repair of cyanobacteria.
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Affiliation(s)
- Anurag Kirti
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
| | - Arvind Kumar
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
| | - Hema Rajaram
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
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3
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C-terminal domain swapping of SSB changes the size of the ssDNA binding site. BIOMED RESEARCH INTERNATIONAL 2014; 2014:573936. [PMID: 25162017 PMCID: PMC4137731 DOI: 10.1155/2014/573936] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 07/09/2014] [Indexed: 01/29/2023]
Abstract
Single-stranded DNA-binding protein (SSB) plays an important role in DNA metabolism, including DNA replication, repair, and recombination, and is therefore essential for cell survival. Bacterial SSB consists of an N-terminal ssDNA-binding/oligomerization domain and a flexible C-terminal protein-protein interaction domain. We characterized the ssDNA-binding properties of Klebsiella pneumoniae SSB (KpSSB), Salmonella enterica Serovar Typhimurium LT2 SSB (StSSB), Pseudomonas aeruginosa PAO1 SSB (PaSSB), and two chimeric KpSSB proteins, namely, KpSSBnStSSBc and KpSSBnPaSSBc. The C-terminal domain of StSSB or PaSSB was exchanged with that of KpSSB through protein chimeragenesis. By using the electrophoretic mobility shift assay, we characterized the stoichiometry of KpSSB, StSSB, PaSSB, KpSSBnStSSBc, and KpSSBnPaSSBc, complexed with a series of ssDNA homopolymers. The binding site sizes were determined to be 26 ± 2, 21 ± 2, 29 ± 2, 21 ± 2, and 29 ± 2 nucleotides (nt), respectively. Comparison of the binding site sizes of KpSSB, KpSSBnStSSBc, and KpSSBnPaSSBc showed that the C-terminal domain swapping of SSB changes the size of the binding site. Our observations suggest that not only the conserved N-terminal domain but also the C-terminal domain of SSB is an important determinant for ssDNA binding.
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Marceau AH, Bernstein DA, Walsh BW, Shapiro W, Simmons LA, Keck JL. Protein interactions in genome maintenance as novel antibacterial targets. PLoS One 2013; 8:e58765. [PMID: 23536821 PMCID: PMC3594151 DOI: 10.1371/journal.pone.0058765] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 02/06/2013] [Indexed: 11/19/2022] Open
Abstract
Antibacterial compounds typically act by directly inhibiting essential bacterial enzyme activities. Although this general mechanism of action has fueled traditional antibiotic discovery efforts for decades, new antibiotic development has not kept pace with the emergence of drug resistant bacterial strains. These limitations have severely restricted the therapeutic tools available for treating bacterial infections. Here we test an alternative antibacterial lead-compound identification strategy in which essential protein-protein interactions are targeted rather than enzymatic activities. Bacterial single-stranded DNA-binding proteins (SSBs) form conserved protein interaction “hubs” that are essential for recruiting many DNA replication, recombination, and repair proteins to SSB/DNA nucleoprotein substrates. Three small molecules that block SSB/protein interactions are shown to have antibacterial activity against diverse bacterial species. Consistent with a model in which the compounds target multiple SSB/protein interactions, treatment of Bacillus subtilis cultures with the compounds leads to rapid inhibition of DNA replication and recombination, and ultimately to cell death. The compounds also have unanticipated effects on protein synthesis that could be due to a previously unknown role for SSB/protein interactions in translation or to off-target effects. Our results highlight the potential of targeting protein-protein interactions, particularly those that mediate genome maintenance, as a powerful approach for identifying new antibacterial compounds.
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Affiliation(s)
- Aimee H. Marceau
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
| | - Douglas A. Bernstein
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
| | - Brian W. Walsh
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Walker Shapiro
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
| | - Lyle A. Simmons
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - James L. Keck
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
- * E-mail:
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5
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Single strand binding proteins increase the processivity of DNA unwinding by the hepatitis C virus helicase. J Mol Biol 2007; 376:69-79. [PMID: 18155046 DOI: 10.1016/j.jmb.2007.10.070] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 10/24/2007] [Accepted: 10/26/2007] [Indexed: 12/19/2022]
Abstract
The nonstructural NS3 protein of the hepatitis C virus is a multifunctional enzyme with an N-terminal serine protease activity and a C-terminal helicase activity. The helicase is capable of unwinding both DNA and RNA duplexes; however, the overall processivity of the helicase is fairly low. We show here that single-strand binding (SSB) proteins enhance the unwinding processivity of both the NS3 helicase domain (NS3h) and the full-length protease-helicase NS3-4A. The detailed study of the effect of SSB on the DNA unwinding activity of NS3h indicates that the SSB stabilizes the helicase at the unwinding junction and prevents its dissociation. These results suggest a potential role for either cellular or virus-encoded SSB protein in improving the processivity of the NS3 in vivo.
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6
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Theobald DL, Wuttke DS. Divergent evolution within protein superfolds inferred from profile-based phylogenetics. J Mol Biol 2005; 354:722-37. [PMID: 16266719 PMCID: PMC1769326 DOI: 10.1016/j.jmb.2005.08.071] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Revised: 08/29/2005] [Accepted: 08/30/2005] [Indexed: 11/19/2022]
Abstract
Many dissimilar protein sequences fold into similar structures. A central and persistent challenge facing protein structural analysis is the discrimination between homology and convergence for structurally similar domains that lack significant sequence similarity. Classic examples are the OB-fold and SH3 domains, both small, modular beta-barrel protein superfolds. The similarities among these domains have variously been attributed to common descent or to convergent evolution. Using a sequence profile-based phylogenetic technique, we analyzed all structurally characterized OB-fold, SH3, and PDZ domains with less than 40% mutual sequence identity. An all-against-all, profile-versus-profile analysis of these domains revealed many previously undetectable significant interrelationships. The matrices of scores were used to infer phylogenies based on our derivation of the relationships between sequence similarity E-values and evolutionary distances. The resulting clades of domains correlate remarkably well with biological function, as opposed to structural similarity, indicating that the functionally distinct sub-families within these superfolds are homologous. This method extends phylogenetics into the challenging "twilight zone" of sequence similarity, providing the first objective resolution of deep evolutionary relationships among distant protein families.
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Affiliation(s)
- Douglas L. Theobald
- Department of Chemistry and Biochemistry, UCB 215 University of Colorado Boulder, CO 80309-0215, USA
| | - Deborah S. Wuttke
- Department of Chemistry and Biochemistry, UCB 215 University of Colorado Boulder, CO 80309-0215, USA
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7
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Lindner C, Nijland R, van Hartskamp M, Bron S, Hamoen LW, Kuipers OP. Differential expression of two paralogous genes of Bacillus subtilis encoding single-stranded DNA binding protein. J Bacteriol 2004; 186:1097-105. [PMID: 14762004 PMCID: PMC344209 DOI: 10.1128/jb.186.4.1097-1105.2004] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2003] [Accepted: 10/31/2003] [Indexed: 11/20/2022] Open
Abstract
The Bacillus subtilis genome comprises two paralogous single-stranded DNA binding protein (SSB) genes, ssb and ywpH, which show distinct expression patterns. The main ssb gene is strongly expressed during exponential growth and is coregulated with genes encoding the ribosomal proteins S6 and S18. The gene organization rpsF-ssb-rpsR as observed in B. subtilis is found in many gram-positive as well as some gram-negative bacteria, but not in Escherichia coli. The ssb gene is essential for cell viability, and like other SSBs its expression is elevated during SOS response. In contrast, the paralogous ywpH gene is transcribed from its own promoter at the onset of stationary phase in minimal medium only. Its expression is ComK dependent and its gene product is required for optimal natural transformation.
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Affiliation(s)
- Cordula Lindner
- Department of Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, NL-9751 NN Haren, The Netherlands
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8
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Hase M, Mizushima T, Katayama T, Sekimizu K. Isolation and characterization of inhibitory factors of DNA polymerase III holoenzyme from Escherichia coli. FEMS Microbiol Lett 1995; 130:215-20. [PMID: 7649443 DOI: 10.1111/j.1574-6968.1995.tb07723.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We isolated fractions by Mono Q chromatography that inhibited the activity of Escherichia coli DNA polymerase III holoenzyme using an assay system with a primed single-stranded DNA template coated with single-stranded DNA binding protein (SSB). The inhibitory activities were inactivated by heat-treatment at 100 degrees C for 10 min, suggesting that they are proteins. The factors did not inhibit the activity of RNA polymerase of Escherichia coli. The inhibitory effects were less potent for the activities of the large (Klenow) fragment of DNA polymerase I and T4 DNA polymerase than for DNA polymerase III holoenzyme. No degradation of single- or double-stranded DNA was observed in the fractions, indicating that inhibition was not due to degradation of the DNA.
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Affiliation(s)
- M Hase
- Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
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9
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Tomonaga T, Levens D. Heterogeneous nuclear ribonucleoprotein K is a DNA-binding transactivator. J Biol Chem 1995; 270:4875-81. [PMID: 7876260 DOI: 10.1074/jbc.270.9.4875] [Citation(s) in RCA: 156] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We have previously reported that heterogeneous nuclear ribonucleoprotein K (hnRNP K) binds to the pyrimidine-rich strand of the CT element found in the human c-myc gene and activates CT reporter-driven gene expression in vivo. We now characterize the DNA and protein requirements for the interaction of hnRNP K with the CT element. First, hnRNP K is shown to preferentially bind single-stranded DNA over RNA or native double-stranded DNA. Using specific oligoribonucleotide or deoxyribonucleotide probes with specific or nonspecific RNA or DNA competitors, electrophoretic mobility shift assay revealed hnRNP K to be a DNA-binding protein. Specific binding was not simply a reflection of binding to pyrimidine-rich sequences as the number and arrangement of individual CT elements governed interactions with hnRNP K; at least two CT repeats separated by at least three nucleotides are required for binding, indicating the existence of particular stereochemical constraints regulating CT-hnRNP K complex formation. Deletion analysis showed that hnRNP K possesses several nonoverlapping, DNA binding domains, each capable of specific binding with the CT element and preferring DNA over RNA. Each sequence recognition domain is composed of at least one K homology motif, while a larger portion of hnRNP K may be required for stable RNA binding. Additional experiments indicate that the N-terminal 35 residues of hnRNP K are necessary for transactivating the CT element. These results indicate that hnRNP K is a DNA-binding protein and transcriptional activator.
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Affiliation(s)
- T Tomonaga
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892
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10
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Kirkpatrick DP, Rao BJ, Radding CM. RNA-DNA hybridization promoted by E. coli RecA protein. Nucleic Acids Res 1992; 20:4339-46. [PMID: 1380698 PMCID: PMC334145 DOI: 10.1093/nar/20.16.4339] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
RecA protein of E. coli plays a central regulatory role that is induced by damage to DNA and results in the inactivation of LexA repressor. In vitro, RecA protein binds preferentially to single-stranded DNA to form a nucleoprotein filament that can recognize homology in naked duplex DNA and promote extensive strand exchange. Although RecA protein shows little tendency at neutral pH to bind to RNA, we found that it nonetheless catalyzed at 37 degrees C the hybridization of complementary RNA and single-stranded DNA sequences. Hybrids made by RecA protein at 37 degrees C appeared indistinguishable from ones prepared by thermal annealing. RNA-DNA hybridization by RecA protein at neutral pH required, as does RecA-promoted homologous pairing, optimal conditions for the formation of RecA nucleoprotein filaments. The cosedimentation of RNA with those filaments further paralleled observations made on the formation of networks of nucleoprotein filaments with double-stranded DNA, an instrumental intermediate in homologous pairing in vitro. These similarities with the pairing reaction support the view that RecA protein acts specifically in the hybridization reaction.
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Affiliation(s)
- D P Kirkpatrick
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06510
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11
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Tateishi S, Horii T, Ogawa T, Ogawa H. C-terminal truncated Escherichia coli RecA protein RecA5327 has enhanced binding affinities to single- and double-stranded DNAs. J Mol Biol 1992; 223:115-29. [PMID: 1731064 DOI: 10.1016/0022-2836(92)90720-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
RecA5327 is a truncated RecA protein that is lacking 25 amino acid residues from the C-terminal end. The expression of RecA5327 protein in the cell resulted in the constitutive induction of SOS functions without damage to the DNA. Purified RecA5327 protein effectively promoted the LexA repressor cleavage reaction and ATP hydrolysis at a lower concentration of single-stranded DNA than that required for wild-type RecA protein. A DNA binding study showed that RecA5327 has about ten times higher affinity for single-stranded DNA than does the wild-type RecA protein. Moreover RecA5327 protein binds stably to double-stranded (ds) DNA in conditions where the wild-type RecA protein could not bind. The binding of RecA5327 protein to dsDNA was associated with the unwinding of dsDNA, suggesting that RecA5327 binds to dsDNA in the same manner as does the wild-type protein. The fact that RecA5327 does not bind stoichiometrically but forms short filaments on dsDNA suggests that it nucleates to dsDNA much more frequently than does the wild-type protein. The role of the 25 C-terminal residues, in the regulation of RecA binding to DNA, is discussed.
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Affiliation(s)
- S Tateishi
- Department of Biology, Faculty of Science Osaka University, Japan
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12
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Curth U, Bayer I, Greipel J, Mayer F, Urbanke C, Maass G. Amino acid 55 plays a central role in tetramerization and function of Escherichia coli single-stranded DNA binding protein. EUROPEAN JOURNAL OF BIOCHEMISTRY 1991; 196:87-93. [PMID: 2001710 DOI: 10.1111/j.1432-1033.1991.tb15789.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The histidine at position 55 of the amino acid sequence of the Escherichia coli single-stranded DNA binding protein was replaced by tyrosine, glutamic acid, lysine, phenylalanine, and isoleucine. The properties of the mutant proteins were determined using analytical ultracentrifugation, NMR spectroscopy, gel filtration, and fluorimetric detection of their single-stranded DNA binding ability. While the phenylalanine and isoleucine substitutions did not change the properties of the protein measurably, tyrosine and lysine mutants dissociate into subunits and loose some of their binding affinity for poly(dT). For the lysine mutant we show by electron microscopy that the protein, although fully dissociated and possibly denatured in the free state, binds to poly(dT) as a tetramer indistinguishable from the wild-type protein. The process of tetramerization as observed via single-stranded DNA binding ability is composed of a variety of steps ranging in time from some milliseconds to several hours; it probably involves several forms of dissociated and non-native protein.
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Affiliation(s)
- U Curth
- Medizinische Hochschule, Zentrum Biochemie, Hannover, Federal Republic of Germany
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13
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Abstract
The single-stranded DNA-binding protein (SSB) of Escherichia coli is involved in all aspects of DNA metabolism: replication, repair, and recombination. In solution, the protein exists as a homotetramer of 18,843-kilodalton subunits. As it binds tightly and cooperatively to single-stranded DNA, it has become a prototypic model protein for studying protein-nucleic acid interactions. The sequences of the gene and protein are known, and the functional domains of subunit interaction, DNA binding, and protein-protein interactions have been probed by structure-function analyses of various mutations. The ssb gene has three promoters, one of which is inducible because it lies only two nucleotides from the LexA-binding site of the adjacent uvrA gene. Induction of the SOS response, however, does not lead to significant increases in SSB levels. The binding protein has several functions in DNA replication, including enhancement of helix destabilization by DNA helicases, prevention of reannealing of the single strands and protection from nuclease digestion, organization and stabilization of replication origins, primosome assembly, priming specificity, enhancement of replication fidelity, enhancement of polymerase processivity, and promotion of polymerase binding to the template. E. coli SSB is required for methyl-directed mismatch repair, induction of the SOS response, and recombinational repair. During recombination, SSB interacts with the RecBCD enzyme to find Chi sites, promotes binding of RecA protein, and promotes strand uptake.
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Affiliation(s)
- R R Meyer
- Department of Biological Sciences, University of Cincinnati, Ohio 45221
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14
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Bayer I, Fliess A, Greipel J, Urbanke C, Maass G. Modulation of the affinity of the single-stranded DNA-binding protein of Escherichia coli (E. coli SSB) to poly(dT) by site-directed mutagenesis. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 179:399-404. [PMID: 2645140 DOI: 10.1111/j.1432-1033.1989.tb14567.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A vector for site-directed mutagenesis and overproduction of the Escherichia coli single-stranded-DNA-binding protein (E. coli SSB) was constructed. An E. coli strain carrying this vector produces up to 400 mg pure protein from 25 g wet cells. The vector was used to mutate specifically the Phe60 residue of E. coli SSB. Phe60 had been proposed to be located near the single-stranded-DNA-binding site. Substitution of the Phe60 residue by Val, Ser, Leu, His, Tyr and Trp gave proteins with no or only minor conformational changes, as detected by NMR spectroscopy. The affinity of the mutant E. coli SSB proteins for single-stranded DNA decreased in the order Trp greater than Phe (wild-type) greater than Tyr greater than Leu greater than His greater than Val greater than Ser, leading to the conclusion that position 60 is a site of hydrophobic interaction of the protein with DNA.
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Affiliation(s)
- I Bayer
- Zentrum Biochemie, Medizinische Hochschule Hannover, Federal Republic of Germany
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15
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Affiliation(s)
- M Kozak
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
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16
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Bujalowski W, Overman LB, Lohman TM. Binding mode transitions of Escherichia coli single strand binding protein-single-stranded DNA complexes. Cation, anion, pH, and binding density effects. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)68829-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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