[effect of temperature on rna synthesis in escherichia coli crt 266 (dna bts) following infection with bacteriophage t3].infection of the temperature-sensitive e. coli crt 266 (dnabts) with t3-phages at the temperature of 30 degrees c and 35 degrees c, respectively, induced t3-specific rna synthesis with a maximum rate at 7 min (30 degrees c) and 4.5 min (35 degrees c) after infection. at temperatures above 40 degrees c no t3-induced rna synthesis could be observed. infection of e. coli cr 34--45 (dnab+) with t3 phages at 30 degrees c, 35 degrees c and at temperatures above 40 degrees c, however, produced t3-speci ...197994483
[use of gen5 and gen6 ts-mutants of phage t3 as indicators of inhibitors of dna synthesis].in an enzyme-specific drug screening system nalidixic acid and 3'-ftdr, inhibitors of dna synthesis, both reduce the growth of wild type and temperature-sensitive point mutants of phage t3 with different efficiencies. the wild type shows the strongest sensitivity against the drugs, while an exonuclease mutant is the most insensitive variant. the dna polymerase mutants exhibit an intermediate degree of inhibition. the anthracycline antibiotics violamycin bi and adriblastin which preferentially in ...1979232593
protein kinase of bacteriophage t7. 2. properties, enzyme synthesis in vitro and regulation of enzyme synthesis and activity in vivo.protein kinase, which was isolated from cells infected with t7, is indeed a viral gene product. this is shown by dna-dependent synthesis in vitro. the protein kinase transfers phosphate from atp to seryl or threonyl residues in protein. the enzyme has only a relative requirement for magnesium ions, but is only active at low ionic strength. the best substrate is lysozyme. t7 protein kinase activity is not stimulated by cyclic 3':5'-amp and/or cyclic 3':5'-gmp. the t7 protein kinase carries -- sh ...1975240695
in vitro packaging of phage t3 dna. 1978664260
mutation in bacteriophage t3 affecting host cell lysis. 1978685184
biological activity of purified bacteriophage t3 prohead and proheadlike structures as precursors for in vitro head assembly. 1978741654
a novel bacteriophage defence mechanism: the anti-restriction protein.bacteriophage t3 and t7 protect their dna from restriction by producing, as the earliest detectable phage functions, anti-restriction proteins. although the two phage proteins differ in their chromatographic and antigenic properties, they act by the same mechanism: the anti-restriction proteins inhibit e. coli k12 restriction endonuclease by direct interaction.1979763348
samase gene of bacteriophage t3 is responsible for overcoming host restriction.deletion and point mutants of t3 have been isolated and used to show that the early region of t3 dna is organized in the same way as that of t7 dna. homologous early rnas and proteins of the two phages have been identified by electrophoresis on polyacrylamide gels in the presence of sodium dodecyl sulfate. both phages have five early mrna's, numbered 0.3, 0.7, 1,1.1 and 1.3 from left to right, although no t3 protein that corresponds to the 1.1 protein of t7 has yet been identified. in general, c ...1976781304
superinfection exclusion by bacteriophage t7.only two of the early genes of bacteriophage t7 were found to play a significant role in exclusion of superinfecting bacteriophage t3 particles; genes 0.3 and 1. protein synthesis by the preinfecting phage particle was not required for efficient exclusion. these findings are discussed with regard to the known functions of these genes during t7 development.1977916034
biological functions of the bacteriophage t3 samase gene.certain differences between phage t3 on the one hand and t3sam- and t7 on the other hand indicate that the t3-coded samase function is responsible (i) for the development of the pseudolysogenic state by preventing t3 dna methylation, and (ii) for the partial protection of the phage dna against restriction by the p system.19751097737
structure analysis of the 5' external transcribed spacer of the precursor ribosomal rna from saccharomyces cerevisiae.full-length precursor ribosomal rna molecules were produced in vitro using as a template, a plasmid containing the yeast 35 s pre-rrna gene under the control of the phage t3 promoter. the higher-order structure of the 5'-external transcribed spacer (5' ets) sequence in the 35s pre-rrna molecule was studied using dimethylsulfate, 1-cyclohexyl-3-(2-morpholinoethyl)-carbodiimide metho-p-toluenesulfonate, rnase t1 and rnase v1 as structure-sensitive probes. modified residues were detected by primer ...19921469716
partial characterization of coliphage wpk and a comparison with coliphage t3.coliphage wpk was originally isolated from sewage in kiel, germany, because its plaque diameter continued to expand for days. electron microscopy revealed an isometric capsid with dimensions of 54 nm between opposite apices, and a short, noncontractile tail 16 nm long, placing phage wpk into morphogroup c1. the nucleic acid of phage wpk was linear double stranded dna. the host ranges of phages wpk and t3 were identical. of ten e. coli strains tested for host range, two were resistant and of eigh ...19921584081
dna-dependent rna polymerase from bacteriophage t3 transcribes and amplifies an rna template in vitro.rna-based amplification systems that have been recently described are dependent upon the presence of more than one enzyme. in an attempt to minimize the number of polymerases required for efficient amplification, we have studied the template specificity of bacteriophage t3 rna polymerase. a synthetic bacteriophage t3 promoter was covalently attached to an rna template. the t3 promoter-rna complex was found to be selective for its native polymerase, and dependent upon the presence of all four rib ...19911718821
genes 1.2 and 10 of bacteriophages t3 and t7 determine the permeability lesions observed in infected cells of escherichia coli expressing the f plasmid gene pifa.infections of f plasmid-containing strains of escherichia coli by bacteriophage t7 result in membrane damage that allows nucleotides to exude from the infected cell into the culture medium. only pifa of the f pif operon is necessary for "leakiness" of the t7-infected cell. expression of either t7 gene 1.2 or gene 10 is sufficient to cause leakiness, since infections by phage containing null mutations in both of these genes do not result in permeability changes of the f-containing cell. even in t ...19911917875
frameshifting in gene 10 of bacteriophage t7.gene 10 of bacteriophage t7, which encodes the most abundant capsid protein, has two products: a major product, 10a (36 kda), and a minor product, 10b (41 kda). 10b is produced by frameshifting into the -1 frame near the end of the 10a coding frame and is incorporated into the capsid. the frameshift occurs at a frequency of about 10% and is conserved in bacteriophage t3. this study shows that sequences important to frameshifting include the originally proposed frameshift site, consisting of over ...19911938901
cross-resistance of escherichia coli b/r to cis-platinum (ii) diamminochloride, uv light and alkylating agents.gradual transfers of the strain escherichia coli b/r on m9 agar with increasing concentrations of cis-platinum (ii) diamminochloride (cis-pt(ii)) yielded a resistant strain sm 405 capable of growing on liquid m9 medium containing 250 mum cis-pt(ii). the parent strain escherichia coli b/r is completely inhibited in both division and growth at cis-pt(ii) concentrations as low as 30 mum. the resistant mutant has a longer doubling time than the parent strain. no other differences were found between ...1975170174
directional cloning of cdna using a selectable sfii increase the efficiency of directionally cloning cdna, we have constructed a pair of vectors and devised a cdna cloning strategy that improves upon previously published methods. the vectors, plib: az and plib: za, have two unique (distinct religation specificities; ggccn/nnnnggcc) sfii sites (sfii.a and sfii.b) flanking a stuffer fragment which contains the tetracycline-resistance element. these vectors permit the directional cloning of cdna in both sense (plib: az) and antisense (plib: za) o ...19902165017
synthesis of functional mrna in mammalian cells by bacteriophage t3 rna polymerase.we found that the 5' nontranslated leader sequence from encephalomyocarditis virus (emcv) allowed transcripts that were synthesized by the t3 rna polymerase in mammalian cells to be translated in a cap-independent fashion. stable mouse cell lines that carry the t3 rna polymerase gene expressed the chloramphenicol acetyltransferase (cat) gene under the control of a phage promoter when the cat gene was fused to the emcv leader and introduced into the cells by transient dna uptake. the level of gen ...19902167433
on a bacteriophage t3 and t4 receptor region within the cell wall lipopolysaccharide of escherichia coli b. 1976772219
termination of transcription by bacteriophage t3 rna polymerase: homogeneous 3'-terminal oligonucleotide sequence of in vitro t3 rna polymerase transcripts.rna was synthesized in vitro from a t3 dna template by t3 rna polymerase and subsequently separated into seven discrete size classes (molecular weights ranging between 0.21 x 10(6) and 6.2 x 10(6)) by electrophoresis in polyacrylamide slab gels. rnase t1-generated 3'-terminal oligonucleotide fragments were then selectively isolated from either the unfractionated total rna or the gel-purified specific transcripts by chromatography on columns of dihydroxyboryl-cellulose. sequence analysis of these ...1979388430
different restriction of bacteriophages t3 and t7 by p1-lysogenic cells and the role of the t3-coded samase.the intracellular growth of the phages t3 and t7 is restricted in the presence of the escherichia coli prophage p1. phage t3 has a higher ability to express its genome and to damage the host cell than t7. this partial protection of t3 against p1 restriction is due to the t3-coded samase, an enzyme which degrades s-adenosylmethionine, the cofactor of the p1 restriction endonuclease. since we did not observe dna cleavage in vivo, we conclude that the in vivo action of the p1 nuclease is limited to ...1977345634
further characterization of bacteriophage t3-induced ribonucleic acid polymerase. studies on the size of in vitro transcripts and interaction of t3 rna polymerase with t3 dna. 1977330532
substitution of a single bacteriophage t3 residue in bacteriophage t7 rna polymerase at position 748 results in a switch in promoter specificity.the bacteriophage t3 and t7 rna polymerases (rnap) are closely related, yet exhibit high specificity for their own promoter sequences. in this work the primary determinant of t7 versus t3 promoter specificity has been localized to a single amino acid residue at position 748 in the t7 rnap. substitution of this residue (asn) with the corresponding residue found in t3 rnap (asp) results in a switch in promoter specificity, and specifically alters recognition of the base pairs (bp) at positions -11 ...19921453460
studies on bacteriophage t3. iii. characterization of capsids as intermediates of the t3 head assembly. 19751089334
effect of temperature on the transcription by bacteriophage t3-induced rna polymerase.bacteriophage t3-induced rna polymerase is rapidly inactivated at 42 degrees c. addition of t3 dna delays this process for 30 s and reduces the rate with which the enzyme activity is lost indicating that a labile binary complex between t3 dna and polymerase must have been formed. the ternary complex between t3-specific rna polymerase, t3 dna, and nascent rna chains obtained when the enzyme is incubated with t3 dna, gtp, atp, and utp is stable to heat (42 degrees c) and only slowly inactivated by ...1979545912
transcription by bacteriophage t3-induced rna polymerase in the presence of kcl and dimethylsulfoxide. 1979442703
properties and biosynthesis of cyclopropane fatty acids in escherichia coli.the lipid phase transition of escherichia coli phospholipids containing cyclopropane fatty acids was compared with the otherwise homologous phospholipids lacking cyclopropane fatty acids. the phase transitions (determined by scanning calorimetry) of the two preparations were essentially identical. infection of e. coli with phage t3 inhibited cyclopropane fatty acid formation over 98%, whereas infection with mutants which lack the phage coded s-adenosylmethionine cleavage enzyme had no effect on ...1979374358
colivirus-t3-coded s-adenosylmethionine hydrolase.bacteriophage t3 induces an enzyme activity which hydrolyzes s-adenosylmethionine. this s-adenosylmethionine hydrolase is interesting, not only because of its unique activity, but also because the protein has to overcome host restriction [f. w. studier and n. r. movva (1976) j. virol. 19, 136-145]. s-adenosylmethionine hydrolase was purified to homogeneity using affinity chromatography on s-adenosylhomocysteine-sepharose. the enzyme occurs in two forms, a and b. form a consists of the viral pept ...1979110588
amino acid sequence of the bacteriophage t5 gene a2 protein.the complete amino acid sequence of the bacteriophage t5-encoded gene a2 protein was determined by protein sequencing. the 134-residue sequence is closely similar to that reported for the product of gene a2-a3 of bacteriophage bf23. segments of the sequence are similar to segments of bacteriophage t4 gene 32 protein, bacteriophage t3 rna polymerase, and the protein encoded by the host gene responsible for isoenzyme conversion of alkaline phosphatase. the similarity of residues 26-46 to a portion ...19912059212
regulated expression of foreign genes in mammalian cells under the control of coliphage t3 rna polymerase and lac that stringently regulate the expression of individual genes within a complex genetic background have contributed greatly to the analysis of gene function. in this report the development of a highly regulated expression system in mammalian cells is described in which transcription of a foreign gene is mediated by the bacteriophage t3 rna polymerase under the control of the escherichia coli lac repressor. rabbit kidney cell lines have been established that constitutively express the phage ...19892664783
analysis of interactions among factors involved in the bacteriophage t3 dna packaging reaction in a defined in vitro system.during head assembly of phage t3, dna is packaged into the cavity of a preformed protein shell, called the prohead, with the aid of noncapsid, packaging proteins, the products of genes 18 and 19 (gp18 and gp19). gp18 and gp19 separately form complexes with dna and proheads, respectively. these complexes associate to form a precursor which can be converted to filled heads by the addition of atp. interactions among factors involved in dna packaging were analyzed. in the presence of atp, gp19 forme ...19911962450
dna sequences necessary for packaging bacteriophage t3 dna.a recombinant plasmid, puce1-tr, carrying a target for processing of the concatemer joint (tr) and sequences to the left of the target (e1), is efficiently packaged into transducing particles during t3 phage infection. using this plasmid packaging/transduction system, the minimal sequences necessary for packaging of t3 dna were determined. the tr sequence contains the targets for initiation cleavage and termination cleavage of concatemer processing (paccr and paccl, respectively). a plasmid lack ...19921546467
substitution of the conserved tryptophan 31 in escherichia coli thioredoxin by site-directed mutagenesis and structure-function analysis.all prokaryotic and eukaryotic thioredoxins contain a conserved tryptophan residue, exposed at the active site disulfide/dithiol. the role of this w31 in escherichia coli thioredoxin (trx) was studied by site-directed mutagenesis. four mutant trx with w31y, w31f, w31h, and w31a replacements were characterized. very low tryptophan fluorescence emission from the remaining w28 was observed in all mutant trx; reduction resulted in large, but variable increases (up to 11-fold) of fluorescence, to lev ...19911999401
topology and phosphorylation of soybean nodulin-26, an intrinsic protein of the peribacteroid membrane.soybean nodulin-26, a homologue of bovine eye lens major intrinsic protein (mip-26), is an integral protein of the peribacteroid membrane in symbiotic root nodules. it comprises 271 amino acids with six potential transmembrane domains and lacks an amino-terminal signal sequence. a full-length nodulin-26 cdna and its various deletion derivatives were transcribed in vitro after linking them to bacteriophage t3 promoter. in vitro translation of these transcripts in a rabbit reticulocyte lysate, in ...19921629242
bacteriophage t3 and t7 early rnas are translated by eukaryotic 80s ribosomes: active phage t3 coded s-adenosylmethionine cleaving enzyme is synthesized.rna transcribed in vitro from the early region of bacteriophage t3 or t7 was translated by cytoplasmic ribosomes which synthesized protein in cell-free systems prepared from mammalian cells and wheat germ. the proteins synthesized in vitro and their counterparts prepared from infected escherichia coli comigrate by polyacrylamide gel electrophoresis with sodium dodecyl sulfate and are similarly affected by deletion or amber bacteriophage mutations. bacteriophage t3 codes for an enzyme that cleave ...19761066688
in vitro cleavage of the concatemer joint of bacteriophage t3 dna.mature dna from phage t3 or t7 is a linear duplex dna with direct repeats at its ends known as "terminally redundant sequences." the dna of these phages is synthesized as concatemers in which unit length molecules are joined together in a head-to-tail fashion through the terminally redundant sequences and processed to form mature dna with coupling to dna packaging. when linearized plasmid dna carrying a concatemer joint, a terminally redundant sequence and its flanking sequences from the concate ...19902294641
specific interaction of the murine transcription termination factor ttf i with class-i rna polymerases.the 18-base-pair sequence element aggtcgaccagtactccg (the sal box) signals termination of mouse ribosomal gene transcription. this sequence is recognized by a sequence-specific dna-binding protein, ttf i, which mediates the termination of transcription by rna polymerase i (pol i). subsequently, the ends of the primary transcripts are trimmed by 10 nucleotides in a sequence-dependent 3'-terminal processing reaction. we have now investigated whether ttf i bound to its target sequence will block el ...19902181320
dissection of functional domains of the packaging protein of bacteriophage t3 by site-directed mutagenesis.intracellular phage t3 dna is synthesized as a concatemer in which unit-length molecules are joined together in head-to-tail fashion through terminally redundant sequences. during packaging of dna, mature monomers are cut from the concatemer. the cutting is obligatorily coupled to dna packaging. the packaging of phage dna is under the control of a pair of noncapsid proteins, called packaging proteins, gp 18 and gp19. gp19 is an atp-binding protein that plays multiple roles in dna packaging. gp19 ...19911989388
bacteriophage t7 morphogenesis and gene 10 frameshifting in escherichia coli showing different degrees of ribosomal fidelity.bacteriophage t7 infection has been studied in escherichia coli strains showing both increased and decreased ribosome fidelity and in the presence of streptomycin, which stimulates translational misreading, in an effort to determine effects on the apparent programmed translational frameshift that occurs during synthesis of the gene 10 capsid protein. quantitation of the protein bands from sds-page failed to detect any significant effects on the amounts of the shifted 10b protein relative to the ...19911766436
three-dimensional structure of t3 connector purified from overexpressing bacteria.the bacteriophage t3 connector has been purified from overexpressed protein in escherichia coli, harboring a plasmid containing the gene encoding p8 protein. the connector, which is composed of 12 copies of p8, has been crystallized in two-dimensional sheets and studied by electron microscopy from negatively stained specimens. a two-dimensional fourier filtering and averaging procedure was performed with crystalline specimens. in addition, single particle averaging techniques were used with othe ...19921548694
a mammalian nicking endonuclease.purification and properties are described for an endonuclease isolated from calf thymus which attacks double-stranded, unmodified dna, primarily by making single-strand breaks. no detectable acid-soluble products arise from the reaction. double-strand breaks may occasionally be produced by the introduction of single-strand breaks on opposite strands in close proximity. the enzyme does not attack denatured dna and is not inhibited by trna. although added divalent cations are not required for acti ...19761276149
inactivation of escherichia coli by near-ultraviolet light and 8-methoxypsoralen: different responses of strains b/r and k-12.a series of escherichia coli k-12 ab1157 strains with normal and defective deoxyribonucleic acid repair capacity were more resistant to treatment with 8-methoxypsoralen (8-mop) and near-ultraviolet light (nuv) than a comparable series of strains from the b/r wp2 family although sensitivities to 254-nm ultraviolet light were closely similar. the difference was most marked with strains deficient in both excision and postreplication repair (uvra reca). the hypothesis that the internal level of 8-mo ...1979378972
infectious measles virus from cloned cdna.the study of measles virus (mv) and of negative strand rna viruses in general has been hampered by the lack of an experimental system for genetic manipulation. here we describe a procedure for generating infectious mv from cloned mv cdna. first we assembled a genetically marked dna copy of the mv genome in plasmids, under the control of phage t3 or t7 promoters, allowing production of transcripts almost identical to the mv genome or antigenome. incubation of these linearized plasmid dnas with th ...19902303032
[host-dependent modifications of bacteriophage t3 expressing changes in adsorption properties (serological study)].the ability of the bacteriophage t3 to adsorb on the host cells of escherichia coli w1655 changes depending on the host strain in which the phage was propagated before. this phenomenon is termed "non-classical" host-controlled modification in contrast to "classical" dna modification. we demonstrate here that t3 phages with various non-classical modifications as well as the host range mutant t3hw differ from each other in the antigenic determinants of the phage adsorption protein.19872442603
ecorii can be activated to cleave refractory dna recognition sites.ecorii restriction sites [5'-cc(a/t)gg] in phage t3 and t7 dna are refractory to cleavage by ecorii, but become sensitive to cleavage in the presence of dnas which contain an abundance of ecorii sensitive sites (e.g. pbr322 or lambda dna). studies using fragments of pbr322 containing different numbers of ecorii sites show that the susceptibility to ecorii cleavage is proportional to the number of sites in the individual fragment. we postulate that ecorii is the prototype of restriction endonucle ...19882836807
relative efficiency of utilization of promoter and termination sites by bacteriophage t3 rna polymerase.bacteriophage t3 rna polymerase promoters have been classified as class ii and class iii on the basis of their relative location in t3 dna as well as on the function of the protein products encoded by the messages transcribed from them. in the present work, the efficiency of utilization of several class ii and class iii promoters by bacteriophage t3 rna polymerase was compared with regard to (a) rate of initiation of transcription as determined by [32p]ppi exchange with gtp; (b) complex formatio ...19892547791
cloning and expression of the bacteriophage t3 rna polymerase gene.the gene that encodes the rna polymerase of bacteriophage t3 (gene 1) has been cloned into a pbr322 derivative under the control of an inducible lacuv5 promoter. large quantities of the protein are synthesized after induction of cells that carry this plasmid. rna polymerase purified from these overproducing cells selectively initiates transcription from t3 promoter sequences as demonstrated by transcription of a dual promoter plasmid that carries both t3 and t7 promoters. cells that carry the t3 ...19863011596
sequence of bacteriophage t3 dna from gene 2.5 through gene 9.the nucleotide sequence of bacteriophage t3 dna, from gene 2.5 through gene 9 has been determined. in addition to regulatory sites, the sequence predicts 19 close-packed genes plus two genes that overlap, in a different reading frame, another gene. the majority of these genes are highly homologous to those in the corresponding region of bacteriophage t7. however, there are some genes that are present in one, but not the other, phage. these apparent deletions are almost exactly gene size and thus ...19892614843
specific contacts between the bacteriophage t3, t7, and sp6 rna polymerases and their promoters.the specificity and structural simplicity of the bacteriophage t3, t7, and sp6 rna polymerases make these enzymes particularly well suited for studies of polymerase-promoter interactions. to understand the initial recognition process between the enzyme and its promoters, dna fragments that carry phage promoters were chemically modified by three different methods: base methylation, phosphate ethylation, and base removal. the positions at which these modifications prevented or enhanced binding by ...19911985921
physical mapping of complex genomes by cosmid multiplex analysis.a rapid and powerful approach for linking individual clones of a cosmid library and the assembly of a large physical map is presented, which depends on the simultaneous analysis of many cosmid clones for overlapping regions. this method uses cosmid vectors that contain endogenous bacteriophage t3 and t7 promoters to allow for the identification of overlapping clones through the synthesis of end-specific rna probes. a genomic library is constructed and organized as an ordered matrix such that eac ...19892740339
discrimination between bacteriophage t3 and t7 promoters by the t3 and t7 rna polymerases depends primarily upon a three base-pair region located 10 to 12 base-pairs upstream from the start site.the bacteriophage t3 and t7 rna polymerases are closely related, yet are highly specific for their own promoter sequences. to understand the basis of this specificity, t7 promoter variant that contain substitutions of t3-specific base-pairs at one or more positions within the t7 promoter consensus sequence were synthesized and cloned. template competition assays between variant and consensus promoters demonstrate that the primary determinants of promoter specificity are located in the region fro ...19902204706
identification of a region of the bacteriophage t3 and t7 rna polymerases that determines promoter specificity.bacteriophages t7 and t3 encode dna-dependent rna polymerases that are 82% homologous, yet exhibit a high degree of specificity for their own promoters. a region of the rna polymerase gene (gene 1) that is responsible for this specificity has been localized using two approaches. first, the rna polymerase genes of recombinant t7 x t3 phage that had been generated in other laboratories in studies of phage polymerase specificity were characterized by restriction enzyme mapping. this approach locali ...19902204707
expression of the unassembled capsid protein during infection of shigella sonnei by bacteriophage t7 results in dna damage that is repairable by bacteriophage t3, but not t7, dna ligase.the abortive infection of bacteriophage t7 in shigella sonnei d2 371-48 is characterized by a premature inhibition of phage dna replication and nucleolytic breakdown of all phage dna. mutations in t7 gene 10 which are recessive to the presence of the wild-type allele can alleviate the restriction of phage growth. phage t3 productively infects s. sonnei d2 371-48, as does a t7-t3 hybrid phage that contains, in particular, a gene 10 of t7 origin. it is the presence of t3 dna ligase that allows pha ...19863522545
sequence of a conditionally essential region of bacteriophage t3, including the primary origin of dna replication.the 3526 base-pair nucleotide sequence from near the end of bacteriophage t3 gene 1 to within the coding sequence of gene 2.5 is given. it includes the complete coding sequences for nine known or presumptive proteins, most of which are only conditionally essential for phage growth. the sequence includes five promoters for the phage rna polymerase, the terminator for early (host enzyme-catalyzed) transcription, and two recognition sites for rnaase iii. the primary origin of t3 dna replication tha ...19873586029
early events in dna packaging in a defined in vitro system of bacteriophage t3.we have developed a defined in vitro system for packaging phage t3 dna which is composed of purified proheads and the noncapsid proteins gp18 and gp19, products of genes 18 and 19. the reaction requires mg2+, atp, and polyethylene glycol and is inhibited by a nonhydrolyzable atp analog, adenosine-5'-o-(3'-thiotriphosphate) (atp-gamma-s) (k. hamada, h. fujisawa, and t. minagawa, 1986, virology 151, 119-123). about 30% of added mature t3 dna was packaged into heads in the defined system. a complex ...19873617498
[effect of temperature on formation of lysozyme in e. coli crt 266 (dnab ts) after infection with bacteriophage t3].lysozyme formation induced by bacteriophage t3 was studied in the ts-mutant e. coli crt 266 (dnabts) and in the wild-type e. coli cr 34--45 (dnab+) at different temperatures. it was found that lysozyme was formed in e. coli crt 266, however, no lysozyme synthesis took place at 41.5 degrees c. these results indicate that the expression of the lysozyme gene is disturbed in the ts-mutant at 41.5 degrees c.1978382720
regulated expression of nuclear genes by t3 rna polymerase and lac repressor, using recombinant vaccinia virus vectors.recombinant vaccinia viruses that express the bacteriophage t3 rna polymerase (vv-t3pol) or the escherichia coli lac repressor (vv-laci) under control of the early-late vaccinia promoter p7.5 were constructed. to determine whether phage polymerase and lac repressor can function in the nucleus of mammalian cells, the bacterial chloramphenicol acetyltransferase (cat) gene was cloned downstream of a t3 promoter (pt3-cat) or downstream of a t3 promoter-lac operator fusion element (pt3olac-cat), and ...19902204724
mitochondrial rna polymerase: dual role in transcription and replication.mitochondrial rna polymerases from humans, xenopus laevis and saccharomyces cerevisiae are very similar in protein composition and function. they consist of a nonspecific core rna polymerase and a protein factor that confers promoter selectivity on the core component, and they participate in transcription as well as in dna replication. amino acid sequence comparisons indicate that the yeast mitochondrial core component is related to bacteriophage t3 and t7 rna polymerases; mitochondrial and phag ...19892667219
nucleotide sequence and complementation studies of the gene 10 region of bacteriophage t3.the nucleotide sequence of bacteriophage t3 gene 10 and surrounding regulatory elements has been determined and compared to the analogous region of bacteriophage t7. t3 genes 9, 10 and 11 have been shown to complement t7 mutants. the dna sequences of t3 and t7 gene 10a are homologous, as are the amino acid sequences of the respective products. the translational shift to the -1 frame is predicted to occur at the same position in gene 10 of t3 and t7, though different nucleotide sequences are prob ...19892760923
subunit arrangement of the tail fiber of bacteriophage t3.a tail fiber of phage t3 is a trimer of the product of gene 17 (gp17). treatment of t3 phage particles with chymotrypsin resulted in cleavage of only the tail fiber protein, at a site near the distal end of the fiber, causing a decrease of about 10% in the size of gp17 in the treated virion. the n-terminal amino acid sequences of intact and cleaved tail fiber proteins were identical and corresponded to that deduced from the nucleotide sequence of gene 17 except for the absence of the initiation ...19862943077
overproduction and purification of the products of bacteriophage t3 genes 18 and 19, two genes involved in dna packaging.the products of gene 18 (gp18) and gene 19 (gp19) of bacteriophage t3 are noncapsid proteins involved in dna packaging. a restriction fragment containing gene 18 or 19 was cloned into the plasmid vector pnt45 under the control of the inducible leftward promoter (pl) of phage lambda. induction of transcription of gene 18 or 19 by derepression of the pl promoter led to the synthesis of a high level of gp18 or gp19. by using complementation of t3 dna packaging in vitro as an assay, gp18 and gp19 we ...19863962187
synthesis of the capsid protein inhibits development of bacteriophage t3 mutants that abortively infect f plasmid-containing cells.mutants of bacteriophage t3 that lack gene 1.2 resemble wild-type phage t7 in that they are unable productively to infect f plasmid-containing cells of escherichia coli. pseudorevertants of a t3 gene 1.2 deletion mutant that have regained the ability to plate efficiently on male cells have been isolated and characterized. at least two mutations in the gene for the major capsid protein are necessary for these phages to bypass f-mediated restriction. one mutation serves to reduce the rate of synth ...19892668535
specific binding of monomeric bacteriophage t3 and t7 rna polymerases to their respective cognate promoters requires the initiating ribonucleoside triphosphate (gtp).bacteriophage t3 and t7 rna polymerases are monomeric proteins of mr of about 100,000. each polymerase has stringent specificity for its own promoters that is present only on the homologous phage dna template. neither enzyme recognizes the heterologous phage promoters or escherichia coli rna polymerase promoters. in the present study, the interaction of t3 and t7 rna polymerases with their respective cognate promoters was studied by dnase i footprinting techniques. these studies revealed an abso ...19862946871
absence of a gene dosage effect during bacteriophage t3- and t7-coded rna polymerase synthesis.the rates of synthesis of phage-coded rna polymerase upon infection of escherichia coli by bacteriophages t3 or t7 were measured at different mois under permissive and non-permissive conditions. at mois from 1 to 15, these rates did not vary appreciably, at mois of about 20 there was a slight depression in the synthesis rate. the reason for this absence of a positive gene dosage effect is unknown.19921740385
high efficiency vectors for cosmid microcloning and genomic analysis.we describe the construction and use of cosmid vectors designed for microcloning, gene isolation and genomic mapping starting from submicrogram amounts of eukaryotic dna. these vectors contain (1) multiple cos sites to allow for simple and efficient cloning using non size-selected dna; (2) bacteriophage t3 and t7 promoter sequences flanking the cloning site to allow for the synthesis of end-specific probes for chromosome walking; (3) a selectable gene for immediate gene transfer of cosmid dna in ...19892777090
characterization of atpase activity of a defined in vitro system for packaging of bacteriophage t3 dna.we have developed a defined in vitro system for packaging phage t3 dna which is composed of purified proheads and the noncapsid proteins gp18 and gp19, products of genes 18 and 19 (k. hamada, h. fujisawa, and t. minagawa, 1986, virology 151, 119-123). the in vitro system displayed an atpase activity. the requirements for atpase activity were the same as those for dna packaging. atpase was inhibited by a nonhydrolyzable atp analog, adenosine-5'-o-(3'-thiotriphosphate) (atp-gamma-s). atpase activi ...19872956757
specificity of ribonucleic acid chain initiation by bacteriophage t3-induced ribonucleic acid polymerase. 19744370385
nucleotide sequence of a major class-iii phage-t3 rna-polymerase promoter located at 98.0% of phage-t3 genetic map.the entire nucleotide sequence of a 409-bp hincii fragment, located within the mboi-e fragment on bacteriophage t3 dna and containing a major class-iii t3 rna polymerase promoter positioned at 98% on the standard t3 genetic map, has been determined. alignment of this class-iii promoter with previously determined t3 rna polymerase promoters, with start points of transcription (+1) in register, indicates high degree of sequence conservation between position -16 to +6 among all t3 rna polymerase pr ...19852989096
initiation, release, and reinitiation of rna chains by bacteriophage-t3-induced polymerase from t3 dna templates (e. coli-guanosine triphosphate terminus-purified polymerase).bacteriophage t3-induced rna polymerase, upon copying its specific template, native t3 dna, initiates rna chains only with gtp. denaturation of the dna results in loss of template specificity for the polymerase. with denatured t3 dna as template, t3 polymerase initiates rna chains with both atp and gtp, and the average length of the resulting rna chains is markedly reduced. studies of the polymerase reaction with native t3 dna in vitro show that t3 polymerase is able to terminate rna synthesis w ...19724550510
three-alpha-helical coiled-coil, as a proposed model for a thin rod segment of bacteriophage t3 tail fibers.three-stranded alpha-helical coiled-coil was considered as a model for a thin proximal rod of t3 phage tail fiber on the basis of amino acid sequence. a segment of residues from ca. 130th to 270th was shown to have a unique feature to satisfy the required conditions of the coiled-coil, and to give the observed geometry.19882963635
studies on bacteriophage t3. i. kinetic studies on particle formation and role of capsids as intermediates of head morphogenesis of bacteriophage t3. 19734579883
[morphogenesis of bacteriophage t3 (author's transl)]. 19734582332
the starting nucleotide sequences and size of rna transcribed in vitro on bacteriophage t3 dna. 19734584696
isolation and characterization of bacteriophage t3/t7 hybrids and their use in studies on molecular basis of dna-packaging vitro dna-packaging systems of bacteriophages t3 and t7 packaged homologous dna more efficiently than heterologous dna. packaging of phage dna proceeds by way of concatemeric intermediates (h. fujisawa, j. miyazaki, and t. minagawa (1978), virology 87, 394-400). the conversion of mature homologous and heterologous dnas to concatemers was efficient in both the t3- and t7-packaging systems. in vitro complementation experiments indicate that the gene 19 product (gp19) specifies which dna enters ...19852998056
[studies of bacteriophage t3. v. further characterization of 2 temperature-sensitive mutants, ts21 and ts25, in escherichia coli b and e. coli ab 2500]. 19734592537
regulation of host ribonucleic acid synthesis in bacteriophage t3-infected cells. properties of an inhibitory protein of escherichia coli ribonucleic acid polymerase. 19744594239
transcription of native and denatured dna preparations by bacteriophage t3 induced rna polymerase. 19744595837
[studies on t3-phases. vi. protein synthesis in a cell-free system from e. coli b after infection with the phage t3]. 19734597936
inactivation of bacteriophage t3 in aerosols: effect of prehumidification on survival after spraying from solutions of salt, peptone, and saliva.coliphage t(3) was inactivated by a factor of 10(3) to 10(4) within 30 min after spraying from solutions of nacl. addition of peptone to the spray medium protected against inactivation at high relative humidity (rh), presumably by preventing surface inactivation. prehumidification of the sample before collection had no effect on recovery if sprayed from solutions of nacl, with or without peptone. if only peptone was present in the spray medium, prehumidification of the aerosol sample increased t ...19744598220
cloning and sequencing of the genetic right end of bacteriophage t3 dna.the genetic right end of phage t3 dna, from the beginning of gene 17, was cloned and sequenced. genes 17, 18, and 19 were identified by comparing the sequence with the genetic map and by comparing the calculated and observed molecular weights of gene products. n-terminal amino acid sequence of the gene 17 product (gp17) predicted from the nucleotide sequence was consistent with the data from the analysis of purified gp17. gene 17.5 was identified as the lysis gene on the basis of the presence of ...19863010556
isolation of dna segments containing promoters from bacteriophage t3 dna. 19744611486
[obtaining a lysate, the concentration and purification of phage t3]. 19744612997
properties of the bacteriophage t3 rna polymerase in vitro. 19724649805
genetic and biochemical analysis of shigella dysenteriae 1 o antigen polysaccharide biosynthesis in escherichia coli k-12: structure and functions of the rfb gene cluster.the genetic organization and functions of the shigella dysenteriae 1 rfb gene cluster, which specifies the somatic o antigen in this organism, have been studied in escherichia coli k-12 by insertion and deletion mutagenesis of pss9, a pbr322 hybrid containing the shigella rfb genes. on the basis of the sensitivity/resistance to rough-specific bacteriophage t3 of e. coli k-12 derivatives containing mutant pss9 plasmids, of the banding patterns and immunoreactivity of lps isolated from such deriva ...19862469933
[t3 phages. iv. isolation of temperature sensitive mutants of phage t3 and their partial characterization]. 19734769109
bacteriophage t3- and t7-directed deoxyribonucleases. 19684911854
synthesis of an s-adenosylmethionine-cleaving enzyme in t3-infected escherichia coli and its disturbance by co-infection with enzymatically incompetent bacteriophage.synthesis of an s-adenosylmethionine-cleaving enzyme evoked by infection of escherichia coli with phage t3 was independent of the multiplicity of infection with the wild type, t3 sam(+). it was depressed, however, by mixed infection with related phages genetically incapable of directing enzyme production, such as t3 sam(-), or phage t7. the depressor effect of enzymatically incompetent genomes depended on their proportion among the input phage and not on their absolute multiplicity. the effect w ...19674918233
bacteriophage t3 connector: three-dimensional structure and comparison with other viral head-tail connecting regions.the bacteriophage t3 connector, which consists of 12 copies of protein gp8, has been studied by image processing of electron micrographs from negatively stained ordered aggregates. a three-dimensional reconstruction of t3 connectors was obtained by collection of tilted views and using the direct fourier method, up to 2.3 nm resolution. the reconstructed unit cell contains two connectors whose main structural features are essentially identical, but facing in opposite directions. the t3 connector ...19883262165
different template specificities of phage t3 and t7 rna polymerases. 19714927023
packaging and transduction of non-t3 dna by bacteriophage t3.a defined in vitro system for packaging t3 dna also packaged other linear dnas, including t4, lambda, and plasmid dnas. the packaging capacity was determined to be 40 kb (kilobase pairs) by measuring the packaged length of t4 dna. packaged lambda and plasmid dnas were injected into host cells to form plaques and transductants, respectively. the yield of transducers increased by using artificially ligated plasmid oligomers. the t3 mutant in gene 3 endonuclease (t3 3-) packaged plasmid dna during ...19882972112
induction of a new rna polymerase in escherichia coli infected with bacteriophage t3. 19714930861
characterization of the bacteriophage t3 dna packaging reaction in vitro in a defined system.the bacteriophage t3 dna packaging system in vitro defined here is composed of purified proheads and two non-capsid proteins, the products of genes 18 and 19 (gp18 and gp19). in this system, a precursor complex (50 s complex) accumulates in the presence of adenosine 5'-o-(3'-thiotriphosphate) (atp-gamma-s), a non-hydrolyzable analog of atp. the 50 s complex is converted to a filled head in the presence of atp. the conversion of the 50 s complex, formed by preincubation with atp-gamma-s, to the m ...19873316664
native and denatured dna of phage t3 and of e. coli b as templates for rna polymerase. 19694975275
genetic analysis of subunit assembly of the tail fiber of bacteriophage t3.bacteriophage t3 virions have six tail fibers composed of the product of gene 17 (gp17). each tail fiber is a trimer of gp17 polypeptide. to characterize the assembly process of the tail fiber, temperature-sensitive (ts) mutants of gene 17 (ts17) were analyzed by sds-polyacrylamide gel electrophoresis and by extract complementation. newly synthesized gp17 polypeptide chains matured to sds-resistant native trimers with a half time of about 7.5 min at 30 degrees. although all ts17 mutants had simi ...19852930941
the photodynamic action of acridine orange and proflavine on the survival of escherichia coli b and its capacity for phage t3. 19665330573
purification and characterization of gene 17 product of bacteriophage t3.tail fiber proteins of bacteriophage t3 are encoded by gene 17. by using in vitro complementation for phage assembly as an assay, the product of gene 17 (gp17) was purified to near homogeneity from cells infected with a double mutant of t3 defective in dna synthesis and head assembly. the purified gp17 consists of a single polypeptide having a molecular weight of 67,000. electron microscopy of the purified gp17 showed a fiber structure similar to the tail fiber in a virion. the subunit structure ...19852930942
the enzymatic methylation of ribonucleic acid and deoxyribonucleic acid. x. bacteriophage t3-induced s-adenosylmethionine cleavage. 19665946625
abortive initiation by bacteriophage t3 and t7 rna polymerases under conditions of limiting substrate.initiation of rna synthesis by the phage polymerases is abortive if the concentration of pyrimidine triphosphates is limiting. under abortive initiation conditions the polymerases repeatedly initiate transcription but produce ribooligonucleotides that terminate just prior to the first occurrence of the limiting substrate. abortive initiation is most severe if the limiting substrate occurs within the first 8-12 nucleotides of the nascent rna chain and is particularly evident when ump is limiting. ...19892646596
derivation of a restriction map of bacteriophage t3 dna and comparison with the map of bacteriophage t7 dna.the dna of bacteriophage t3 was characterized by cleavage with seven restriction endonucleases. avai, xbai, bglii, and hindiii each cut t3 dna at 1 site, kpni cleaved it at 2 sites, mboi cleaved it at 9 sites, and hpai cleaved it at 17 sites. the sizes of the fragments produced by digestion with these enzymes were determined by using restriction fragments of t7 dna as molecular weight standards. as a result of this analysis, the size of t3 dna was estimated to be 38.74 kilobases. the fragments w ...19806251266
sequence and analysis of the gene for bacteriophage t3 rna polymerase.the rna polymerases encoded by bacteriophages t3 and t7 have similar structures, but exhibit nearly exclusive template specificities. we have determined the nucleotide sequence of the region of t3 dna that encodes the t3 rna polymerase (the gene 1.0 region), and have compared this sequence with the corresponding region of t7 dna. the predicted amino acid sequence of the t3 rna polymerase exhibits very few changes when compared to the t7 enzyme (82% of the residues are identical). significant dif ...19853903658
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