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Kenneth N. Kreuzer

Professor Emeritus of Biochemistry
Biochemistry
Duke Box 3711, Durham, NC 27710
155A Nanaline Duke Bldg, Durham, NC 27710

Selected Publications


Functional Analysis of the Bacteriophage T4 Rad50 Homolog (gp46) Coiled-coil Domain.

Journal Article J Biol Chem · September 25, 2015 Rad50 and Mre11 form a complex involved in the detection and processing of DNA double strand breaks. Rad50 contains an anti-parallel coiled-coil with two absolutely conserved cysteine residues at its apex. These cysteine residues serve as a dimerization do ... Full text Link to item Cite

Mutations that Separate the Functions of the Proofreading Subunit of the Escherichia coli Replicase.

Journal Article G3 (Bethesda) · April 15, 2015 The dnaQ gene of Escherichia coli encodes the ε subunit of DNA polymerase III, which provides the 3' → 5' exonuclease proofreading activity of the replicative polymerase. Prior studies have shown that loss of ε leads to high mutation frequency, partially c ... Full text Link to item Cite

Functions that protect Escherichia coli from DNA-protein crosslinks.

Journal Article DNA Repair (Amst) · April 2015 Pathways for tolerating and repairing DNA-protein crosslinks (DPCs) are poorly defined. We used transposon mutagenesis and candidate gene approaches to identify DPC-hypersensitive Escherichia coli mutants. DPCs were induced by azacytidine (aza-C) treatment ... Full text Link to item Cite

Functions that Protect Escherichia coli from Tightly Bound DNA-Protein Complexes Created by Mutant EcoRII Methyltransferase.

Journal Article PLoS One · 2015 Expression of mutant EcoRII methyltransferase protein (M.EcoRII-C186A) in Escherichia coli leads to tightly bound DNA-protein complexes (TBCs), located sporadically on the chromosome rather than in tandem arrays. The mechanisms behind the lethality induced ... Full text Link to item Cite

Replication of the Escherichia coli chromosome in RNase HI-deficient cells: multiple initiation regions and fork dynamics.

Journal Article Mol Microbiol · January 2014 DNA replication in Escherichia coli is normally initiated at a single origin, oriC, dependent on initiation protein DnaA. However, replication can be initiated elsewhere on the chromosome at multiple ectopic oriK sites. Genetic evidence indicates that init ... Full text Link to item Cite

DNA damage responses in prokaryotes: regulating gene expression, modulating growth patterns, and manipulating replication forks.

Journal Article Cold Spring Harbor perspectives in biology · November 1, 2013 Recent advances in the area of bacterial DNA damage responses are reviewed here. The SOS pathway is still the major paradigm of bacterial DNA damage response, and recent studies have clarified the mechanisms of SOS induction and key physiological roles of ... Cite

Coordination and processing of DNA ends during double-strand break repair: the role of the bacteriophage T4 Mre11/Rad50 (MR) complex.

Journal Article Genetics · November 2013 The in vivo functions of the bacteriophage T4 Mre11/Rad50 (MR) complex (gp46/47) in double-strand-end processing, double-strand break repair, and recombination-dependent replication were investigated. The complex is essential for T4 growth, but we wanted t ... Full text Link to item Cite

DNA damage responses in prokaryotes: regulating gene expression, modulating growth patterns, and manipulating replication forks.

Journal Article Cold Spring Harb Perspect Biol · November 1, 2013 Recent advances in the area of bacterial DNA damage responses are reviewed here. The SOS pathway is still the major paradigm of bacterial DNA damage response, and recent studies have clarified the mechanisms of SOS induction and key physiological roles of ... Full text Link to item Cite

Recombination-Dependent DNA Replication

Chapter · February 15, 2013 For many years, homologous genetic recombination and DNA replication were studied in isolation from one another. However, beginning with studies of bacteriophages in the 1960s and 1970s, the possibility emerged that extensive DNA replication can sometimes ... Full text Cite

The T4 phage SF1B helicase Dda is structurally optimized to perform DNA strand separation.

Journal Article Structure · July 3, 2012 Helicases move on DNA via an ATP binding and hydrolysis mechanism coordinated by well-characterized helicase motifs. However, the translocation along single-stranded DNA (ssDNA) and the strand separation of double-stranded (dsDNA) may be loosely or tightly ... Full text Link to item Cite

Crystal structure of the phage T4 recombinase UvsX and its functional interaction with the T4 SF2 helicase UvsW.

Journal Article J Mol Biol · January 7, 2011 Bacteriophage T4 provides an important model system for studying the mechanism of homologous recombination. We have determined the crystal structure of the T4 UvsX recombinase, and the overall architecture and fold closely resemble those of RecA, including ... Full text Link to item Cite

Initiation of bacteriophage T4 DNA replication and replication fork dynamics: a review in the Virology Journal series on bacteriophage T4 and its relatives.

Journal Article Virol J · December 3, 2010 Bacteriophage T4 initiates DNA replication from specialized structures that form in its genome. Immediately after infection, RNA-DNA hybrids (R-loops) occur on (at least some) replication origins, with the annealed RNA serving as a primer for leading-stran ... Full text Link to item Cite

Importance of the tmRNA system for cell survival when transcription is blocked by DNA-protein cross-links.

Journal Article Mol Microbiol · November 2010 Anticancer drug 5-azacytidine (aza-C) induces DNA-protein cross-links (DPCs) between cytosine methyltransferase and DNA as the drug inhibits methylation. We found that mutants defective in the tmRNA translational quality control system are hypersensitive t ... Full text Link to item Cite

Fork regression is an active helicase-driven pathway in bacteriophage T4.

Journal Article EMBO Rep · April 2009 Featured Publication Reactivation of stalled replication forks requires specialized mechanisms that can recognize the fork structure and promote downstream processing events. Fork regression has been implicated in several models of fork reactivation as a crucial processing ste ... Full text Link to item Cite

The epsilon subunit of DNA polymerase III Is involved in the nalidixic acid-induced SOS response in Escherichia coli.

Journal Article J Bacteriol · August 2008 Quinolone antibacterial drugs such as nalidixic acid target DNA gyrase in Escherichia coli. These inhibitors bind to and stabilize a normally transient covalent protein-DNA intermediate in the gyrase reaction cycle, referred to as the cleavage complex. Sta ... Full text Link to item Cite

Regression supports two mechanisms of fork processing in phage T4.

Journal Article Proc Natl Acad Sci U S A · May 13, 2008 Featured Publication Replication forks routinely encounter damaged DNA and tightly bound proteins, leading to fork stalling and inactivation. To complete DNA synthesis, it is necessary to remove fork-blocking lesions and reactivate stalled fork structures, which can occur by m ... Full text Link to item Cite

The phage T4 protein UvsW drives Holliday junction branch migration.

Journal Article J Biol Chem · November 23, 2007 Featured Publication The phage T4 UvsW protein has been shown to play a crucial role in the switch from origin-dependent to recombination-dependent replication in T4 infections through the unwinding of origin R-loop initiation intermediates. UvsW also functions with UvsX and U ... Full text Link to item Cite

5-Azacytidine induced methyltransferase-DNA adducts block DNA replication in vivo.

Journal Article Cancer Res · September 1, 2007 Featured Publication 5-Azacytidine (aza-C) and its derivatives are cytidine analogues used for leukemia chemotherapy. The primary effect of aza-C is the prohibition of cytosine methylation, which results in covalent methyltransferase-DNA (MTase-DNA) adducts at cytosine methyla ... Full text Link to item Cite

Formation and processing of stalled replication forks--utility of two-dimensional agarose gels.

Journal Article Methods Enzymol · 2006 Replication forks can be stalled by tightly bound proteins, DNA damage, nucleotide deprivation, or defects in the replication machinery. It is now appreciated that processing of stalled replication forks is critical for completion of DNA replication and ma ... Full text Link to item Cite

Genetic analysis of the requirements for SOS induction by nalidixic acid in Escherichia coli.

Journal Article Gene · August 15, 2005 Nalidixic acid, the prototype antibacterial quinolone, induces the SOS response by a mechanism that requires the RecBCD nuclease/helicase. A key step inferred for this induction pathway is the conversion of a drug-induced gyrase cleavage complex into a DNA ... Full text Link to item Cite

Bacteriophage T4 helicase loader protein gp59 functions as gatekeeper in origin-dependent replication in vivo.

Journal Article J Biol Chem · June 3, 2005 Bacteriophage T4 initiates origin-dependent replication via an R-loop mechanism in vivo. During in vitro reactions, the phage-encoded gp59 stimulates loading of the replicative helicase, gp41, onto branched intermediates, including origin R-loops. However, ... Full text Link to item Cite

Norfloxacin-induced DNA gyrase cleavage complexes block Escherichia coli replication forks, causing double-stranded breaks in vivo.

Journal Article Mol Microbiol · June 2005 Featured Publication Antibacterial quinolones inhibit type II DNA topoisomerases by stabilizing covalent topoisomerase-DNA cleavage complexes, which are apparently transformed into double-stranded breaks by cellular processes such as replication. We used plasmid pBR322 and two ... Full text Link to item Cite

2004 ASM Conference on the New Phage Biology: the 'Phage Summit'.

Journal Article Mol Microbiol · March 2005 In August, more than 350 conferees from 24 countries attended the ASM Conference on the New Phage Biology, in Key Biscayne, Florida. This meeting, also called the Phage Summit, was the first major international gathering in decades devoted exclusively to p ... Full text Link to item Cite

Interplay between DNA replication and recombination in prokaryotes.

Journal Article Annu Rev Microbiol · 2005 Featured Publication The processes of DNA replication and recombination are intertwined at many different levels. In diverse systems, extensive DNA replication can be triggered by genetic recombination, with assembly of a replication complex onto a D-loop recombination interme ... Full text Link to item Cite

Isolation of SOS constitutive mutants of Escherichia coli.

Journal Article J Bacteriol · November 2004 Featured Publication The bacterial SOS regulon is strongly induced in response to DNA damage from exogenous agents such as UV radiation and nalidixic acid. However, certain mutants with defects in DNA replication, recombination, or repair exhibit a partially constitutive SOS r ... Full text Link to item Cite

The crystal structure of the UvsW helicase from bacteriophage T4.

Journal Article Structure · April 2004 In bacteriophage T4, the WXY system repairs DNA damage by a process that involves homologous recombination. This system comprises three proteins, the RecA-like recombination protein UvsX, a recombination mediator protein UvsY, and a helicase UvsW. Here we ... Full text Link to item Cite

Endonuclease cleavage of blocked replication forks: An indirect pathway of DNA damage from antitumor drug-topoisomerase complexes.

Journal Article Proc Natl Acad Sci U S A · April 29, 2003 Featured Publication The cytotoxicity of several important antitumor drugs depends on formation of the covalent topoisomerase-DNA cleavage complex. However, cellular processes such as DNA replication are necessary to convert the cleavage complex into a cytotoxic lesion, but th ... Full text Link to item Cite

Coordination of DNA ends during double-strand-break repair in bacteriophage T4.

Journal Article Genetics · November 2002 Featured Publication The extensive chromosome replication (ECR) model of double-strand-break repair (DSBR) proposes that each end of a double-strand break (DSB) is repaired independently by initiating extensive semiconservative DNA replication after strand invasion into homolo ... Full text Link to item Cite

A unique type II topoisomerase mutant that is hypersensitive to a broad range of cleavage-inducing antitumor agents.

Journal Article Biochemistry · June 25, 2002 Bacteriophage T4 provides a useful model system for dissecting the mechanism of action of antitumor agents that target type II DNA topoisomerases. Many of these inhibitors act by trapping the cleavage complex, a covalent complex of enzyme and broken DNA. P ... Full text Link to item Cite

Replication, recombination, and repair: going for the gold.

Journal Article Mol Cell · March 2002 DNA recombination is now appreciated to be integral to DNA replication and cell survival. Recombination allows replication to successfully maneuver through the roadblocks of damaged or collapsed replication forks. The signals and controls that permit cells ... Full text Link to item Cite

The tight linkage between DNA replication and double-strand break repair in bacteriophage T4.

Journal Article Proc Natl Acad Sci U S A · July 17, 2001 Featured Publication Double-strand break (DSB) repair and DNA replication are tightly linked in the life cycle of bacteriophage T4. Indeed, the major mode of phage DNA replication depends on recombination proteins and can be stimulated by DSBs. DSB-stimulated DNA replication i ... Full text Link to item Cite

Bacteriophage T4 gene 41 helicase and gene 59 helicase-loading protein: a versatile couple with roles in replication and recombination.

Journal Article Proc Natl Acad Sci U S A · July 17, 2001 Bacteriophage T4 uses two modes of replication initiation: origin-dependent replication early in infection and recombination-dependent replication at later times. The same relatively simple complex of T4 replication proteins is responsible for both modes o ... Full text Link to item Cite

Repair of topoisomerase-mediated DNA damage in bacteriophage T4.

Journal Article Genetics · May 2001 Type II topoisomerase inhibitors are used to treat both tumors and bacterial infections. These inhibitors stabilize covalent DNA-topoisomerase cleavage complexes that ultimately cause lethal DNA damage. A functional recombinational repair apparatus decreas ... Full text Link to item Cite

Recognition and specific degradation of bacteriophage T4 mRNAs.

Journal Article Genetics · May 2001 Gene 61.5 of bacteriophage T4 has a unique role in gene expression. When this gene is mutated, mRNAs of many late genes are rapidly degraded, resulting in late-gene silencing. Here, we characterize an extragenic suppressor, ssf5, of a gene 61.5 mutation. s ... Full text Link to item Cite

UvsW protein regulates bacteriophage T4 origin-dependent replication by unwinding R-loops.

Journal Article Mol Cell Biol · April 2001 Featured Publication The UvsW protein of bacteriophage T4 is involved in many aspects of phage DNA metabolism, including repair, recombination, and recombination-dependent replication. UvsW has also been implicated in the repression of origin-dependent replication at late time ... Full text Link to item Cite

Substitutions in bacteriophage T4 AsiA and Escherichia coli sigma(70) that suppress T4 motA activation mutations.

Journal Article J Bacteriol · April 2001 Bacteriophage T4 middle-mode transcription requires two phage-encoded proteins, the MotA transcription factor and AsiA coactivator, along with Escherichia coli RNA polymerase holoenzyme containing the sigma(70) subunit. A motA positive control (pc) mutant, ... Full text Link to item Cite

Two types of recombination hotspots in bacteriophage T4: one requires DNA damage and a replication origin and the other does not.

Journal Article Genetics · March 2001 Recombination hotspots have previously been discovered in bacteriophage T4 by two different approaches, marker rescue recombination from heavily damaged phage genomes and recombination during co-infection by two undamaged phage genomes. The phage replicati ... Full text Link to item Cite

Bacteriophage T4 proteins replicate plasmids with a preformed R loop at the T4 ori(uvsY) replication origin in vitro.

Journal Article Mol Cell · January 2001 Featured Publication Bacteriophage T4 DNA replication proteins catalyze complete unidirectional replication of plasmids containing the T4 ori(uvsY) replication origin in vitro, beginning with a preformed R loop at the position of the origin R loop previously identified in vivo ... Full text Link to item Cite

Double-strand break repair in tandem repeats during bacteriophage T4 infection.

Journal Article Genetics · August 2000 Recombinational repair of double-strand breaks in tandemly repeated sequences often results in the loss of one or more copies of the repeat. The single-strand annealing (SSA) model for repair has been proposed to account for this nonconservative recombinat ... Full text Link to item Cite

Recombination-dependent DNA replication in phage T4.

Journal Article Trends Biochem Sci · April 2000 Studies in the 1960s implied that bacteriophage T4 tightly couples DNA replication to genetic recombination. This contradicted the prevailing wisdom of the time, which staunchly supported recombination as a simple cut-and-paste process. More-recent investi ... Full text Link to item Cite

The importance of repairing stalled replication forks.

Journal Article Nature · March 2, 2000 Featured Publication The bacterial SOS response to unusual levels of DNA damage has been recognized and studied for several decades. Pathways for re-establishing inactivated replication forks under normal growth conditions have received far less attention. In bacteria growing ... Full text Link to item Cite

An antitumor drug-induced topoisomerase cleavage complex blocks a bacteriophage T4 replication fork in vivo.

Journal Article Mol Cell Biol · January 2000 Featured Publication Many antitumor and antibacterial drugs inhibit DNA topoisomerases by trapping covalent enzyme-DNA cleavage complexes. Formation of cleavage complexes is important for cytotoxicity, but evidence suggests that cleavage complexes themselves are not sufficient ... Full text Link to item Cite

Bacteriophage T4 initiates bidirectional DNA replication through a two-step process.

Journal Article Mol Cell · November 1998 Featured Publication Two-dimensional gel analysis of the bacteriophage T4 ori(uvsY) region revealed a novel "comet" on the Y arc. This comet contains simple Y molecules in which the branch points map to the ori(uvsY) transcript region. The comet depends on the the origin and D ... Full text Link to item Cite

Bacteriophage T4, a model system for understanding the mechanism of type II topoisomerase inhibitors.

Journal Article Biochim Biophys Acta · October 1, 1998 Bacteriophage T4 provides a simple model system for analyzing the mechanism of action of antitumor agents that inhibit DNA topoisomerases. The phage-encoded type II topoisomerase is sensitive to many of the same antitumor agents that inhibit mammalian type ... Full text Link to item Cite

The MotA transcriptional activator of bacteriophage T4 binds to its specific DNA site as a monomer.

Journal Article Biochemistry · April 7, 1998 During bacteriophage T4 middle mode gene expression, the MotA transcription factor binds to T4 middle promoters at a -30 mot box consensus sequence to allow activation. Previous binding studies showed that MotA forms multiple gel-shifted complexes with DNA ... Full text Link to item Cite

Mutations of the bacteriophage T4 type II DNA topoisomerase that alter sensitivity to antitumor agent 4'-(9-acridinylamino)methanesulfon-m-anisidide and an antibacterial quinolone.

Journal Article Cancer Res · March 15, 1998 Various antitumor and antibacterial agents target type II DNA topoisomerases, stabilizing a cleaved DNA reaction intermediate and thereby converting topoisomerase into a cellular poison. Two 4'-(9-acridinylamino)methanesulfon-m-anisidide (m-AMSA)-resistant ... Link to item Cite

Bacteriophage T4 UvsW protein is a helicase involved in recombination, repair and the regulation of DNA replication origins.

Journal Article EMBO J · July 1, 1997 Bacteriophage T4 UvsW protein is involved in phage recombination, repair and the regulation of replication origins. Here, we provide evidence that UvsW functions as a helicase. First, expression of UvsW allows growth of an (otherwise inviable) Escherichia ... Full text Link to item Cite

The activation domain of the MotA transcription factor from bacteriophage T4.

Journal Article EMBO J · April 15, 1997 Bacteriophage T4 encodes a transcription factor, MotA, that binds to the -30 region of middle-mode promoters and activates transcription by host RNA polymerase. We have solved the structure of the MotA activation domain to 2.2 A by X-ray crystallography, a ... Full text Link to item Cite

RNA-DNA hybrid formation at a bacteriophage T4 replication origin.

Journal Article J Mol Biol · March 14, 1997 The bacteriophage T4 replication origins ori(uvsY) and ori(34) each contain two distinct components: a T4 middle-mode promoter that is strictly required for replication and a downstream region of about 50 bp that is required for maximal levels of replicati ... Full text Link to item Cite

Repair of double-strand breaks in bacteriophage T4 by a mechanism that involves extensive DNA replication.

Journal Article Genetics · August 1996 We investigated double-strand break (dsb) repair in bacteriophage T4 using a physical assay that involves a plasmid substrate with two inverted DNA segments. A dsb introduced into one repeat during a T4 infection induces efficient dsb repair using the seco ... Full text Link to item Cite

Bacteriophage T4 mutants hypersensitive to an antitumor agent that induces topoisomerase-DNA cleavage complexes.

Journal Article Genetics · July 1996 Many antitumor agents and antibiotics affect cells by interacting with type II topoisomerases, stabilizing a covalent enzyme-DNA complex. A pathway of recombination can apparently repair this DNA damage. In this study, transposon mutagenesis was used to id ... Full text Link to item Cite

Identification, cloning, and expression of the Escherichia coli pyrazinamidase and nicotinamidase gene, pncA.

Journal Article Antimicrob Agents Chemother · June 1996 Pyrazinamide (PZA) is one of the three most important drugs for treatment of Mycobacterium tuberculosis infections. The antibacterial activity of PZA requires a bacterial enzyme, pyrazinamidase (PZAase), which hydrolyzes PZA to form pyrazinoic acid and amm ... Full text Link to item Cite

Role of recombinational repair in sensitivity to an antitumour agent that inhibits bacteriophage T4 type II DNA topoisomerase.

Journal Article Mol Microbiol · June 1996 The bacteriophage T4-encoded type II DNA topoisomerase is the major target for the antitumour agent m-AMSA (4'-(9-acridinylamino)methanesulphonm-ansidide) in phage-infected bacterial cells. Inhibition of the purified enzyme by m-AMSA results in formation o ... Full text Link to item Cite

Two-dimensional gel analysis of rolling circle replication in the presence and absence of bacteriophage T4 primase.

Journal Article Nucleic Acids Res · June 1, 1996 The rolling circle DNA replication structures generated by the in vitro phage T4 replication system were analyzed using two-dimensional agarose gels. Replication structures were generated in the presence or absence of T4 primase (gp61), permitting the anal ... Full text Link to item Cite

Recombination-dependent DNA replication stimulated by double-strand breaks in bacteriophage T4.

Journal Article J Bacteriol · December 1995 We analyzed the mechanism of recombination-dependent DNA replication in bacteriophage T4-infected Escherichia coli using plasmids that have sequence homology to the infecting phage chromosome. Consistent with prior studies, a pBR322 plasmid, initially resi ... Full text Link to item Cite

Disruption of a topoisomerase-DNA cleavage complex by a DNA helicase.

Journal Article Proc Natl Acad Sci U S A · December 6, 1994 The type II DNA topoisomerases are targets for a variety of chemotherapeutic agents, including the antibacterial quinolones and several families of antitumor drugs. These agents stabilize an enzyme-DNA cleavage complex that consists of the topoisomerase co ... Full text Link to item Cite

Integration of plasmids into the bacteriophage T4 genome.

Journal Article Genetics · December 1994 We have analyzed the integration of plasmids into the bacteriophage T4 genome via homologous recombination. As judged by genetic selection for a plasmid-borne marker, a mutation in phage gene uvsX or uvsY essentially blocked the integration of a plasmid wi ... Full text Link to item Cite

Localization of an aminoacridine antitumor agent in a type II topoisomerase-DNA complex.

Journal Article Proc Natl Acad Sci U S A · November 8, 1994 Type II topoisomerases are the targets of several classes of chemotherapeutic agents that stabilize an intermediate of the catalytic cycle with the enzyme covalently linked to cleaved DNA. We have used 3-azido-AMSA [4'-(3-azido-9-acridinylamino)methanesulf ... Full text Link to item Cite

ANALYSIS OF ORIGIN-DEPENDENT DNA-REPLICATION INITIATION IN BACTERIOPHAGE-T4

Journal Article JOURNAL OF CELLULAR BIOCHEMISTRY · February 13, 1994 Link to item Cite

A DNA HELICASE INDUCES TOPOISOMERASE II-ASSOCIATED DNA BREAKS

Journal Article JOURNAL OF CELLULAR BIOCHEMISTRY · February 13, 1994 Link to item Cite

A bacteriophage model system for studying topoisomerase inhibitors.

Journal Article Adv Pharmacol · 1994 The bacteriophage T4 provides a unique and informative system in which to study the mechanism of action of antitumor agents that inhibit type II DNA topoisomerases. The evolutionary conservation of inhibitor sensitivity provides a strong argument for a con ... Full text Link to item Cite

Differentially labeled mutant oligonucleotides for analysis of protein-DNA interactions.

Journal Article Biotechniques · January 1994 We have developed a method to produce a set of four duplex oligonucleotides, each with a different labeled base at a given position, from one template-primer combination. The template oligonucleotide is synthesized with a mixture of all four bases at the p ... Link to item Cite

The MotA protein from bacteriophage T4 contains two domains. Preliminary structural analysis by X-ray diffraction and nuclear magnetic resonance.

Journal Article J Mol Biol · July 5, 1993 Controlled protease cleavage experiments and N-terminal sequence analyses were used to show that the transcriptional activator MotA from bacteriophage T4 has a two-domain structure. The N and C-terminal domains have M(r) values of 10,300 and 11,800, respec ... Full text Link to item Cite

Mutational analysis of a type II topoisomerase cleavage site: distinct requirements for enzyme and inhibitors.

Journal Article EMBO J · May 1993 We have analyzed the DNA sequence requirements for cleavage of a 30 bp oligonucleotide that contains a strong bacteriophage T4 type II topoisomerase site. A novel method was used to generate substrates with each of the four nucleotides at 10 positions surr ... Full text Link to item Cite

Deletion of the essential gene 24 from the bacteriophage T4 genome.

Journal Article Gene · January 15, 1993 We deleted the essential gene 24 from the genome of bacteriophage T4. The delta 24 phage is a conditional lethal mutant that can grow only when the host strain supplies the product of gene 24 in trans, or when the phage acquires a functional gene 24 by som ... Full text Link to item Cite

Plasmid models for bacteriophage T4 DNA replication: requirements for fork proteins.

Journal Article J Virol · December 1992 Bacteriophage T4 DNA replication initiates from origins at early times of infection and from recombinational intermediates as the infection progresses. Plasmids containing cloned T4 origins replicate during T4 infection, providing a model system for studyi ... Full text Link to item Cite

Role of MotA transcription factor in bacteriophage T4 DNA replication.

Journal Article J Mol Biol · November 5, 1992 At least two bacteriophage T4 replication origins, ori(uvsY) and ori(34), contain a T4 middle-mode promoter that is necessary for origin function. We wanted to analyze the requirement of these two replication origins for the MotA protein, which is the phag ... Full text Link to item Cite

Purified MotA protein binds the -30 region of a bacteriophage T4 middle-mode promoter and activates transcription in vitro.

Journal Article J Biol Chem · June 5, 1992 The bacteriophage T4-encoded MotA protein is critical for transcription from T4 middle-mode promoters. However, a direct interaction of this protein with a middle-mode promoter has not previously been demonstrated. We have cloned the motA gene and overexpr ... Link to item Cite

A system of transposon mutagenesis for bacteriophage T4.

Journal Article Mol Microbiol · May 1992 We have developed a system of transposon mutagenesis for bacteriophage T4. The transposon is a plasmid derivative of Tn5 which contains the essential T4 gene 24, permitting a direct selection for transposition events into a gene 24-deleted phage. The trans ... Full text Link to item Cite

Recombination hotspots in bacteriophage T4 are dependent on replication origins.

Journal Article Proc Natl Acad Sci U S A · July 15, 1991 Bacteriophage T4 recombination "hotspots" were first detected by the rescue of genetic markers from UV-irradiated phage particles. These hotspots have since been detected following treatments that yield other forms of DNA damage, and at least one is active ... Full text Link to item Cite

The specificity of topoisomerase-mediated DNA cleavage defines acridine-induced frameshift specificity within a hotspot in bacteriophage T4.

Journal Article Genetics · March 1991 Acridine-induced frameshift mutations in bacteriophage T4 occur at the precise location in the DNA at which acridines stimulate DNA cleavage by the T4-encoded type II topoisomerase in vitro. The mutations are duplications or deletions that begin precisely ... Full text Link to item Cite

Evidence for a common mechanism of action for antitumor and antibacterial agents that inhibit type II DNA topoisomerases.

Journal Article J Biol Chem · November 25, 1990 Numerous antitumor and antibacterial agents inhibit type II DNA topoisomerases, yielding, in each case, a complex of enzyme covalently bound to cleaved DNA. We are investigating the mechanism of inhibitor action by using the type II DNA topoisomerase of ba ... Link to item Cite

Expression and function of the uvsW gene of bacteriophage T4.

Journal Article J Mol Biol · August 5, 1990 The uvsW gene of bacteriophage T4 is involved in many aspects of phage DNA metabolism, including replication, recombination and repair. To approach the function of uvsW, the structure and expression of the uvsW gene were first explored. Molecular analyses ... Full text Link to item Cite

Mutational alteration of the breakage/resealing subunit of bacteriophage T4 DNA topoisomerase confers resistance to antitumor agent m-AMSA.

Journal Article Mol Gen Genet · March 1990 Bacteriophage T4 provides a simple model system in which to examine the mechanism of action of antitumor agents that have been proposed to attack type II DNA topoisomerases. Prior results demonstrated that T4 type II DNA topoisomerase is the target of anti ... Full text Link to item Cite

Bacteriophage T4 DNA topoisomerase is the target of antitumor agent 4'-(9-acridinylamino)methanesulfon-m-anisidide (m-AMSA) in T4-infected Escherichia coli.

Journal Article Proc Natl Acad Sci U S A · February 1989 The mammalian type II DNA topoisomerase has been proposed to be the intracellular target of a variety of antitumor agents, including m-AMSA [4'-(9-acridinylamino)-methanesulfon-m-anisidide]. Because the bacteriophage T4-encoded topoisomerase resembles the ... Full text Link to item Cite

Recombination-dependent replication of plasmids during bacteriophage T4 infection.

Journal Article J Biol Chem · August 15, 1988 The replication of plasmids containing fragments of the T4 genome, but no phage replication origins, was analyzed as a possible model for phage secondary (recombination-dependent) replication initiation. The replication of such plasmids after T4 infection ... Link to item Cite

The bacteriophage T4 insertion/substitution vector system. A method for introducing site-specific mutations into the virus chromosome.

Journal Article J Biol Chem · August 15, 1988 A bacteriophage T4 insertion/substitution vector system has been developed as a means of introducing in vitro generated mutations into the T4 chromosome. The insertion/substitution vector is a 2638-base pair plasmid containing the pBR322 origin of replicat ... Link to item Cite

Deletion analysis of bacteriophage T4 tertiary origins. A promoter sequence is required for a rifampicin-resistant replication origin.

Journal Article J Biol Chem · August 15, 1988 The DNA sequence requirements of two T4 tertiary replication origins have been characterized by a deletion analysis of origin-containing plasmids. Maximal replication of each origin-containing plasmid required both an intact gpmotA-dependent middle-mode pr ... Link to item Cite

Tertiary initiation of replication in bacteriophage T4. Deletion of the overlapping uvsY promoter/replication origin from the phage genome.

Journal Article J Biol Chem · August 15, 1988 Tertiary initiation of bacteriophage T4 DNA replication is resistant to the RNA polymerase inhibitor rifampicin and apparently involved in the activity of recombination hot spots in the T4 genome (Kreuzer, K. N., and Alberts, B. M. (1985) Proc. Natl. Acad. ... Link to item Cite

Hotspot sites for acridine-induced frameshift mutations in bacteriophage T4 correspond to sites of action of the T4 type II topoisomerase.

Journal Article J Mol Biol · April 20, 1988 The type II topoisomerase of bacteriophage T4 is a central determinant of the frequency and specificity of acridine-induced frameshift mutations. Acridine-induced frameshift mutagenesis is specifically reduced in a mutant defective in topoisomerase activit ... Full text Link to item Cite

Characterization of a defective phage system for the analysis of bacteriophage T4 DNA replication origins.

Journal Article J Mol Biol · March 20, 1986 We have developed a defective phage system for the isolation and analysis of phage T4 replication origins based on the T4-mediated transduction of plasmid pBR322. During the initial infection of a plasmid-containing cell, recombinant plasmids with T4 DNA i ... Full text Link to item Cite

PHAGE-T4 REPLICATION ORIGINS THAT COINCIDE WITH RECOMBINATION HOTSPOTS

Journal Article JOURNAL OF CELLULAR BIOCHEMISTRY · January 1, 1986 Link to item Cite

SEQUENCE-ANALYSIS OF PHAGE-T4 TERTIARY ORIGINS

Journal Article JOURNAL OF CELLULAR BIOCHEMISTRY · January 1, 1986 Link to item Cite

A defective phage system reveals bacteriophage T4 replication origins that coincide with recombination hot spots.

Journal Article Proc Natl Acad Sci U S A · May 1985 Plasmid transduction mediated by bacteriophage T4 has been used to study putative T4 DNA replication origins cloned as inserts in the Escherichia coli plasmid pBR322. Two particular inserts from the T4 genome allow high-frequency plasmid transduction, sugg ... Full text Link to item Cite

Site-specific recognition of bacteriophage T4 DNA by T4 type II DNA topoisomerase and Escherichia coli DNA gyrase.

Journal Article J Biol Chem · April 25, 1984 The site specificity of bacteriophage T4-induced type II DNA topoisomerase action on double-stranded DNA has been explored by studying the sites where DNA cleavages are induced by the enzyme. Oxolinic acid addition increases the frequency at which phi X174 ... Link to item Cite

Recognition of single-stranded DNA by the bacteriophage T4-induced type II topoisomerase.

Journal Article J Biol Chem · April 25, 1984 The bacteriophage T4-induced type II DNA topoisomerase has been shown previously to make a reversible double strand break in DNA double helices. In addition, this enzyme is shown here to bind tightly and to cleave single-stranded DNA molecules. The evidenc ... Link to item Cite

Escherichia coli phage T4 topoisomerase.

Journal Article Methods Enzymol · 1983 Full text Link to item Cite

STUDIES ON DNA-REPLICATION IN THE BACTERIOPHAGE-T4 INVITRO SYSTEM

Journal Article ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · January 1, 1982 Link to item Cite

Formation and resolution of DNA catenanes by DNA gyrase.

Journal Article Cell · May 1980 We have discovered that DNA gyrase interlocks duplex DNA circles to form catenanes and resolves catenanes into component monomers. The reactions were inhibited by novobiocin and oxolinic acid and required ATP, Mg++ and spermidine. DNA sequence homology is ... Full text Link to item Cite

SHAPING OF DNA BY DNA GYRASE

Journal Article ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · January 1, 1980 Link to item Cite

Escherichia coli mutants thermosensitive for deoxyribonucleic acid gyrase subunit A: effects on deoxyribonucleic acid replication, transcription, and bacteriophage growth.

Journal Article J Bacteriol · November 1979 Temperature-sensitive nalA mutants of Escherichia coli have been used to investigate the structure and functions of deoxyribonucleic acid (DNA) gyrase. Extracts of one such mutant (nalA43) had thermosensitive DNA gyrase subunit A activity but normal gyrase ... Full text Link to item Cite

Structure and activities of Escherichia coli DNA gyrase.

Journal Article Cold Spring Harb Symp Quant Biol · 1979 Full text Link to item Cite

Lambda transducing phages for the nalA gene of Escherichia coli and conditional lethal nalA mutations.

Journal Article Mol Gen Genet · November 29, 1978 Defective lambda transducing phages for the nalA region of the Escherichia coli chromosome were isolated from a lysogen in which lambda is inserted in the nearby glpT gene. The three classes of transducing phages designated lambdanrdA, lambdaubiG, and lamb ... Full text Link to item Cite

DNA GYRASE - TARGET FOR NALIDIXIC-ACID IN CELLULAR DNA-REPLICATION

Journal Article JOURNAL OF SUPRAMOLECULAR STRUCTURE · January 1, 1978 Link to item Cite

Mechanism of action of nalidixic acid: purification of Escherichia coli nalA gene product and its relationship to DNA gyrase and a novel nicking-closing enzyme.

Journal Article Proc Natl Acad Sci U S A · November 1977 A target protein for nalidixic and oxolinic acids in Escherichia coli, the nalA gene product (Pnal), was purified to homogeneity as judged by gel electrophoresis, using an in vitro complementation assay. It is a dimer of identical 110,000-dalton subunits. ... Full text Link to item Cite

Genetic analysis of regulatory mutants of alkaline phosphatase of E. coli.

Journal Article Genetics · November 1975 A fine structure map of the phoR region of E. coli, mutations of which affect the rate of alkaline phosphatase synthesis, was constructed by Hfr X F- crosses. Mutations causing three different phenotypes (previously reported as phoRa, phoRb, phoRc (Garen a ... Full text Link to item Cite