Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| inactivation of lambda phage infectivity and lambda deoxyribonucleic acid transfection by n-methyl-isatin beta-thiosemicarbazone-copper complexes. | the infectivity of intact lambda phage and transfection by lambda deoxyribonucleic acid were inactivated by exposure to the copper complexes of n-methyl-isatin beta-thiosemicarbazone, thiosemicarbazide, and semicarbazide, but not methyl-isatin. no inactivation was observed when these compounds were used in the absence of copper sulfate. this confirms our previous observation that the activity of n-methyl-isatin beta-thiosemicarbazone is mediated by its thiosemicarbazone moiety and that the prese ... | 1976 | 769669 |
| deletions of lambda phage locating a prm mutation within the rightward operator. | two deletion-substitution mutations of phage lambda, spi-113 and spi-274, are shown to remove about half of the rightward operator or. physiological studies show that spi-113 is still repressible. thus, the 50 or so nucleotides of or deleted in this mutant are not absolutely essential for repression. prm-116, which inactivates the promoter essential for the maintenance of lambda repressor synthesis, is located within or between the endpoints of spi-113 and spi-274. | 1976 | 1062780 |
| determination of nucleotide sequences beyond the sites of transcriptional termination. | a procedure is described by which a discrete high-molecular-weight rna transcription product can be used as a primer by dna polymerase (dna nucleotidyltransferase; ec 2.7.7.7; deoxynucleoside triphosphate: dna deoxynucleotidyltransferase) for determining nucleic acid sequence in the template dna beyond the 3'-terminus of the transcript. this procedure is applied to two lambda phage transcripts, the 4s "oop" rna [short l-strand rna transcript from the region of origin of replication (ori) and the ... | 1976 | 1062781 |
| purification and properties of a dna-binding protein with characteristics expected for the cro protein of bacteriophage lambda, a repressor essential for lytic growth. | the cro protein specified by bacteriophage lambda is a repressor essential for normal lytic growth of the virus, thus having a physiological role distinct from that of ci, the repressor that maintains lysogeny. we have purified a lambda-specific dna-binding protein with the requirements for synthesis and biochemical activities expected for cro protein from studies in vivo. as isolated, the protein appears to be a dimer of molecular weight approximately 18,000 with dna-binding properties that are ... | 1976 | 1065873 |
| improved derivative of a phage lambda ek2 vector for cloning recombinant dna. | 1976 | 1067476 | |
| methods for identification of recombinants of phage lambda. | two methods are described which allow the screening of a large number of phage plaques for a specific dna sequence carried by the phage or a specific antigen produced within the phage plaque. these methods were set up with lambda and lambdalac phages. phage plaques were transferred onto nitrocellulose filters by desiccation in 0.1 m naoh, and the lac sequence was detected by hybridization to radioactive lac mrna. beta-galactosidase was detected by reaction with anti-beta-galactosidase immune ser ... | 1976 | 1068453 |
| restriction assay for integrative recombination of bacteriophage lambda dna in vitro: requirement for closed circular dna substrate. | a novel assay has been developed for in vitro genetic recombination of dna. substrate and product dnas are cleaved with a restriction endonuclease and the resulting fragments are separated by electrophoresis in agarose gels. the substrate dna has been chosen so that the recombination to be studied deletes a segment of dna. the remaining dna gives rise to a unique restriciton fragment, as does the dna segment that has been removed. the method provides a convenient and physical, rather than geneti ... | 1976 | 1068464 |
| construction of a hybrid col e1 plasmid carrying the gene for bacteriophage lambda repressor. | a biologically active hybrid dna molecule was constructed from plasmid col e1 and the eco r1 fragment of lambda dna containing the gene for lambda repressor. the presence of this gene in the hybrid molecule was demonstrated genetically. the hybrid plasmid contains two closely located targets for restriction endonuclease hind 111 in the integrated fragment. thus, the plasmid may be used as a vector not only for eco r1 fragments but also for hind 111 fragments. | 1976 | 1069256 |
| integration of eukaryotic genes for 5s rna and histone proteins into a phage lambda receptor. | highly purified hindiii restriction fragments of xenopus laevis 5s dna and of psammechinus miliaris histone dna have been covalently inserted into a derivative of phage lambda. this phage, genetically constructed by murray et al. (1), contains only a single target for hindiii in the ci gene. viable hybrid molecules were detected as clear plaque-forming phage after transfection of e. coli, the vast majority of which were shown by hybridization to be recombinants of the desired type. the lambdasam ... | 1976 | 1069257 |
| colicin e2 is dna endonuclease. | colicin e2 purified by conventional methods contains a tightly bound low-molecular-weight protein, as has been found with purified colicin e3 [jakes,n.&zinder,n.d.(1974) proc. natl. acad. sci. usa 71, 3380-3384]. such e2 preparations do not cause dna cleavage in vitro. after separation from the low-molecular-weight protein, colicin e2 retained the original in vivo killing activity, and in addition showed a high activity in vitro in cleaving various dna molecules, such as a cole1 hybrid plasmid a ... | 1976 | 1069283 |
| construction of plasmids carrying the ci gene of bacteriophage lambda. | by techniques of recombination in vitro, we have constructed a plasmid bearing the repressor gene (ci) of bacteriophage lambda fused to the promoter of the lac operon. strains carrying this plasmid overproduce lambda repressor. this functional ci gene was reconstituted by joining dna fragments bearing different parts of that gene. flush end fusion techniques, involving no sequence overlap, were necessary for the construction; in certain cases, the abutting of the dna molecules bearing ends gener ... | 1976 | 1069307 |
| single burst study of rec- and red-mediated recombination in bacteriophage lambda. | single bursts from three-point crosses of bacteriophage lambda were analyzed for recombination of markers several thousand nucleotide pairs apart. single recombination, mediated by the rec system of escherichia coli, is usually reciprocal. double recombinants are also significantly correlated in single bursts, although the correlation is weaker than for reciprocal singles. reciprocity is not found in crosses mediated by the lambda red system. with respect to certain other paraments of recombinat ... | 1976 | 1070013 |
| [genetic and functional characterization of mutants of the lambda phage affected in the regulation of lysogenization]. | 1976 | 1070772 | |
| [new mutagens of bacteriophage lambda affected during lysogeny regulation]. | 1976 | 1071226 | |
| internal inversion used to study regulation of the int gene in bacteriophage lambda. | 1976 | 934307 | |
| 4s oop rna is a leader sequence for the immunity-establishment transcription in coliphage lambda. | oop rna, which is initiated at the po promoter and is 81 nucleotides long, can function as a leader sequence for the lambda immunity establishment transcription, previously believed to originate at a special promoter pre located in the y region. thus, oop rna seems to have a dual role, either favouring the lytic cycle as a primer for the initiation of lambda dna replication, or leading to the establishment of lysogeny when elongated into the imm transcript, which directs synthesis of the repress ... | 1976 | 934330 |
| [study of the virustatic action of rimantadine based on a phage-bacterium model]. | the action of rimantadin on the lambda phages was studied. the maximal inhibitory effect on the compound was observed on the 1st-6th minutes after the infection. there was no such effect on the t-4 and lambda phage replication. according to the data of incorporation of the radioactive precursors into the phage dna, rna, and proteins, and the manifestation of the rimantadin action on phage replication it was supposed that the inhibitory effect of rimantadin was determined by its influence on th ... | 1976 | 947381 |
| a reinvestigation of 5' leads to 3' polarity in 40s ribosomal rna precursor of xenopus laevis. | the 5' leads to 3' polarity of the 40s precursor rrna molecule relative to the location of the 18s and 28s rna regions in the precursor has been reinvestigated. fragments of rdna derived by the restriction endonuclease ecori and cloned in e. coli were partially digested with the exonuclease induced by bacteriophage lambda and with exonuclease iii from e. coli. the resulting rdna fragments with single-stranded tails were hybridized separately with 18s and 28s rrna, and the formation of the hybri ... | 1976 | 954098 |
| genetic exchanges caused by ultraviolet photoproducts in phage lambda dna molecules: the role of dna replication. | genetic recombination induced by structural damage in dna molecules was investigated in e. coli k12 (lambda) lysogens infected with genetically marked phage lambda. photoproducts were induced in the phage dna before infection by exposing them either to 313 nm light in the presence of acetophenone or to 254 nm light. to test the role of the replication of the damaged phage dna on the frequency of the induced recombination, both heteroimmune and homimmune crosses were performed. first, samples of ... | 1976 | 958200 |
| autoregulation and function of a repressor in bacteriophage lambda. | 1976 | 959843 | |
| synthesis of morphogenetic proteins by mutants of bacteriophage lambda carrying tandem genetic duplications. | 1976 | 960570 | |
| interaction of host and viral regulatory mechanisms: effect of the ion cell division defect on regulation of repression by bacteriophage lambda. | 1976 | 966281 | |
| the capsid protein of bacteriophage lambda and of its prehead. | 1976 | 966283 | |
| protection of particular cleavage sites of restriction endonucleases by distamycin a and actinomycin d. | it is shown here that distamycin a and actinomycin d can protect the recognition sites of endo r.ecori, ecorii, hindii, hindiii, hpai and hpaii from the attack of these restriction endonucleases. at proper distamycin concentrations only two endo r.ecori sites of phage lambda dna are available for the restriction enzyme--sri1 and sri4. this phenomenon results in the appearance of larger dna fragments comprising several consecutive fragments of endo r.ecori complete cleavage. the distamycin fragme ... | 1976 | 967694 |
| [mapping of phage lambda dna using the antibiotic distamycin]. | 1976 | 971663 | |
| formation of covalently closed cyclic dimers and catenanes of escherichia coli phage lambda in the absence of known recombination systems. | 1976 | 982813 | |
| nucleotide clusters in deoxyribonucleic acids. xiv. pyrimidine oligonucleotides of the left and right halves and lambdadv region of bacteriophage lambda dna. | 1976 | 982832 | |
| inhibition of bacteriophage lambda, t1, and t7 development by r plasmids of the h incompatibility group. | r plasmids from chloramphenicol-resistant salmonella from ontario are shown to belong to the h(2) incompatibility subgroup and to mediate a broad-spectrum, phage inhibition function. | 1976 | 984810 |
| substrate specificity of the ultraviolet-endonuclease from micrococcus luteus. endonucleolytic cleavage of depurinated dna. | the ultraviolet-endonuclease isolated from micrococcul luteus, specific for pyrimidine dimers, is able to attack not only ultraviolet-irradiated dna (leading to 3'oh-5'po4 single-strand breaks) but also superhelical covalently-closed circular dna of phage lambda damaged by heating at 70 degrees c, ph 5.93. the number of endonuclease-sensitive defects in the dna corresponds to the number of alkalilabile bonds (apurinic sites) induced by heating. competition between ultraviolet-induced lesions and ... | 1976 | 991858 |
| [substrate of a uv-induced repair system providing for w-reactivation of lambda phage]. | escherichia coli uvra, pola and uvrd cells carrying non-uv-inducible prophage lambdac1857ind- were infected with 3h-thymidine labelled homoimmune phage lambdac1857, and the effect of uv-irradiation of super-infecting phage and lysogenic bacterial cells on the content of intracellular covalently-closed lambda dna circles (cccdna) and pyrimidine dimer content in lambda dna are studied. uv-irradiation of host cells results in two-fold increase of relative content of cccdna of uv-irradiated phage la ... | 1976 | 1001892 |
| morphogenesis of bacteriophage lambda tail. polymorphism in the assembly of the major tail protein. | 1976 | 1003470 | |
| heat-sensitive dna-binding activity of the ci product of bacteriophage lambda. | the binding of lambda gene ci product to lambda dna was studied at temperatures from 0 degrees c to 46 degrees c. binding activity of the products of cits mutants was higher at 22 degrees c than at 0 degrees c, 26 degrees c or 30 degrees c. both ci+ and cits products lost dna-binding activity at 46 degrees c, but after subsequent cooling to 22 degrees c, they regained 50-100% of their activity. | 1976 | 1004487 |
| the use of terminal blocking groups for the specific joining of oligonucleotides in rna ligase reactions containing equimolar concentrations of acceptor and donor molecules. | under the conditions that rna ligase converts the tetranucleotide, pa-a2-a, to larger polynucleotides, no such polymerization can be detected with the derivative, pa-a2-a(meoet), that possesses a terminal 2'-0-(alpha-methoxyethyl) group. the protection against self condensation offered by the methoxyethyl group in this system allows the specific joining of donor and acceptor oligonucleotides in reaction mixtures containing equimolar concentrations of the two species. thus, the enzyme, together w ... | 1976 | 1005114 |
| a complex control circuit. regulation of immunity in temperate bacteriophages. | temperate bacteriophages can display in a stable way two essentially different behaviours. in the immune state, a gene (ci) produces a repressor which prevents expression of all the other viral genes; in the non-immune state the typically viral functions are expressed. the choice between the two pathways and the establishment of one of them have much in common with cell determination and differentiation. this choice depends on a complex control system, in fact one of the most intricate nets of r ... | 1976 | 1009948 |
| [new lambdoid escherichia coli phages. i. isolation, group immunity and recombination with lambda phage]. | 550 bacterial strains were isolated from sewage. 69 of them were lysogenic by phages active on escherichia coli. the phages were divided into two groups on the basis of uv-inducibility, the ability to form plaques on rep-e. coli mutants and particle morphology: lambdoid (23 phages) and related to p2 (46 phages). hybrid phages isolated from the crosses of lambdoid phages with phage lambda harboured the region imm lambda and the gene of adsorption specificity from other parent. ten groups of heter ... | 1976 | 1010326 |
| [new lambdoid phages of escherichia coli. ii. comparison of several genetic characteristics with lambda phages]. | functions of some newly isolated lambdoid phages and phage lambda genes were compared by their ability to interact with unrelated phages and the product of the bacterial gene gro p. 19 of 23 lambdoid phages studied interfere with prophage p2, that points out the presence of functionally active genes, essential for spi+ phenotype in their genomes. the development of 4 lambdoid phages with spi- phenotype is independent on the prophage p2 presence. most of lambdoid phages show the reduced growth ab ... | 1976 | 1010327 |
| analysis of a temperature sensitive mutation in gene cii of bacteriophage lambda. | the mutation ciits612 was found to map outside the immunity region of phage lambdaimm21 hybrid. as expected of a cii mutation, lambdaciits612 is unable to stimulate either ci repressor or int synthesis during the establishment of lysogeny. these results indicate that part of the cii gene of lambda is homologous to that of lambdaimm21 phage. | 1976 | 1012266 |
| isolation of suppressor sensitive mutants in the ai gene of phage lambda. | previous experiments have shown that mutations in the ai gene can suppress the growth defect of lambda n- phages. many temperature resistant derivatives of phage lambdatsn9 have been isolated and among these 5 have been found which are ai- and have an amber suppressible behaviour. these mutants can help in defining the role of the ai gene in phage lambda development. | 1976 | 1012269 |
| the site-specific deoxyribonuclease from bacillus pumilus (endonuclease r.bpu1387). | a new site-specific endonuclease (dnase) was isolated from the cells of bacillus pumilus ahu 1387 strain. this enzyme (endonuclease r.bpu 1387) introduced double-stranded scissions at unique sites on dna's of coli phage lambda, lambdadvl, coli phage t7, bacillus phage phi105c, bacillus phage sp10, and simian virus 40, in the presence of magnesium ion. the activity was stimulated by the presence of nacl. | 1976 | 1018024 |
| renaturation of bacteriophage lambda dna. determination of the optimal renaturation conditions using a single-strand-specific dnase and alkaline-sucrose-gradient assay system. | reannealed hybrid molecules of wild-type bacteriophage lambda dna were prepared in aqueous solutions of formamide at a variety of nacl concentrations at both room temperature ( 22 degrees c) and 37 degrees c. treatment of the hybrid dna molecules with the single-strand-specific nuclease s1 from aspergillus oryzae followed by alkaline sucrose gradient sedimentation was used to monitor the extent and fidelity of hybridization. the optimal renaturation conditions at room temperature were found to b ... | 1976 | 1248479 |
| hyperfine structure in melting profile of bacteriophage lambda dna. | 1976 | 1252601 | |
| surface structure of in vitro assembled bacteriophage lambda polyheads. | 1976 | 1255721 | |
| functional empty capsid precursors produced by lambda mutant defective for late lambda dna replication. | this report described lambda phage morphogenesis in a mutant system in which the normal pathways for late phage dna (concatemer) synthesis are blocked and early (monomeric circular) dna replication products accumulate. as shown earlier (dawson et al., 1975) under these conditions, late proteins are synthesized and assembled into headlike structures. these structures that accumulate in the mutant are empty, suggesting the monomeric circular dna molecules cannot be encapsulated. the present result ... | 1976 | 1255849 |
| red system of bacteriophage lambda complements the growth of a bacteriophage t1 gene 4 mutant. | the ability of phage lambda to complement the growth of t1am23, a t1 gene 4 mutant with a dna arrest phenotype, has been shown to require both lambda red functions, redx and redb. lambdagam function, however, is not required. therefore, the lambda red function can substitute for t1 gene 4 function. however, t1+ does not substitute for lambda red in allowing lambda to grow in a pola host. | 1976 | 1255855 |
| dual transcription of the tryptophan operon translocated into the early region of gamma. | the mode of transcription of the trp operon translocated into the early region of bacteriophage lambda was studied. synthesis of trp mrna specific for the translocated trp operon in lambdatrp phage was assayed after infecting a bacteria carrying a deletion mutant (trpae1), which lacks the whole trp operon but retains a trp regulator gene (trpr). to determine trp mrna from lambdatrp, phage phi80trp was employed as a source of dna in hybridization assays. trp mrna synthesis by lambdatrpe-a, which ... | 1976 | 1268252 |
| differential sensitivity to antibiotics of trp mrna synthesis originating at the trp promoter and the lambda promoter. | transcription of the escherichia coli trp operon translocated into the early region of bacteriophage lambda can occur under the control of either of two promoters, the trp promoter on the lambda promoter (ol of n gene). (imamato, f. and tani, s. (1972) nat. new biol. 240, 172-175 and ihara s. and imamoto, f. (1976) biochim. biophys. acta 432, 199-211). trp mrna synthesis originating at the trp promoter stopped when translation was blocked by chloramphenicol tetracycline erythromycin or puromycin ... | 1976 | 1268253 |
| on recombination between close and distant markers in phage lambda. | the contribution of parental dna to progeny phages genetically recombinant for close markers, distant markers, or both simultaneously was studied in biparental and triparental replication-blocked crosses. the data are compatible with the previously proposed view that heterozygous overlaps at the sites of crossing over are sometimes about as long as the lambda chromosome. however, about half of the close marker recombinants have enjoyed triparental interactions, attenuating that conclusion and ob ... | 1976 | 1269911 |
| host dna replication or excision repair requirement for ultraviolet induction of bacteriophage lambda lysogens. | 1976 | 1272389 | |
| sepcific fragmentation of dna heteroduplex molecules of two bacteriophage lambda mutants with endonuclease si from aspergillus oryzae. | heteroduplex dna molecules of two bacteriophage mutants (lambda b2 and lambda i434ct68) were obtained by the method of molecular hybridization. these heteroduplexes possessed two types of loops formed as a result of: a) deletion in one of the dna strands; and b) substitution of a dna fragment for nonhomological one. the digestion of heteroduplexes with single-stranded specific nuclease si from aspergillus oryzae produced two fragments at 37 degrees c and three ones at 55 degrees c. the separatio ... | 1976 | 1272803 |
| processing of the major leftward mrna of coliphage lambda. | 1976 | 1274177 | |
| visualization of prokaryotic dna in a regularly condensed chromatin-like fiber. | electron microscopy of disrupted escherichia coli cells under certain conditions revealed loops of a fiber 120 a in diameter which were attached to the cell envelope and showed a 130 a repeating beaded substructure. these fibers were detected only when the cells were lysed in 0.15 m nacl solutions directly on the electron microscope supporting films and if the dehydration steps began within 2 min of lysis. under these conditions examination of cells lysogenic for phage lambda after superinfectio ... | 1976 | 1108025 |
| phage lambda dna injection into escherichia coli pel- mutants is restored by mutations in phage genes v or h. | 1976 | 1108413 | |
| genetic and physiological studies of abortive infections of hydroxymethyluracil-containing bacteriophages in lysogens of temperate bacillus subtilis bacteriophage spo2. | wild-type bacteriophage phie and is (interference-sensitive) mutants of the related phage sp82g did not productively infect strains of bacillus subtilis that were lysogenic for temperate phage spo2. in these abortive infections, the sensitive phages adsorbed to and penetrated the nonpermissive host, phage-directed macromolecular syntheses were initiated, but both viral and bacterial nucleic acid production abruptly stopped about 15 min after addition of the phages. the cessation of rna and dna s ... | 1976 | 818410 |
| dna of myxococcus bacteriophage mx-1: macromolecular properties and restriction fragments. | 1. bacteriophage mx-1 is a virulent dna phage whose hosts include strains of myxococcus xanthus, m. fulvus and m. virescens. dna was extracted from purified phage preparations. the molecular weight of phage dna was measured by sedimentation-velocity and by rate-zonal ultracentrifugation. the apparent molecular weight was found to vary for reasons discussed in the text. from rate-zonal ultracentrifugation, using calibrated sucrose gradients, the molecular weight was calculated to be 149 (+/-22) x ... | 1976 | 818975 |
| prophage map of converting corynebacteriophage beta. | a prophage map for corynebacteriophage beta consisting of seven markers has been constructed and compared with the vegetative map. the mapping system utilizes heteroimmune double lysogens and capitalizes on the fact that these double lysogens are very unstable and throw off monolysogenic segregants. the prophage map, produced by characterizing the recombinant phage in these monolysogenic segregants, appears to be a cyclic permutation of the vegetative map with the gene for toxin at one end of th ... | 1976 | 820872 |
| orientation of the tox gene in the prophage of corynebacteriophage beta. | the orientation of the gene for diphtheria toxin, tox, in the prophage of converting corynebacteriophage beta has been determined. the orientation of tox in prophage and that reported simultaneously by holmes (1976) for vegetative phage are compatible with the hypothesis that beta phage is inserted into the chromosome of its bacterial host by means of a mechanism similar to that described for lambda phage, and that the phage attachment site lies between the tox and imm genes. the position of thr ... | 1976 | 820874 |
| [preparation of molecules combining phage lambda and bacillus subtilis dnas by the sticky end addition method]. | 1976 | 824113 | |
| lambda cin-1, a new mutation which enhances lysogenization by bacteriophage lambda, and the genetic structure of the lambda cy region. | seven lambda cy mutants have been mapped within a small region located approximately halfway between the rightward boundary of the imm434 region and the lambda cii gene. the seven mutants lie at four sites separated by a total distance of about 12 nucleotide pairs, as estimated from recombination frequencies. six of the seven mutants lie on the right side of the cy fine structure map, spanning a total distance of about 3-5 nucleotide pairs. lying approximately 11-21 nucleotide pairs to the left ... | 1976 | 773742 |
| on the nature of cis-acting regulatory proteins and genetic organization in bacteriophage: the example of gene q of bacteriophage lambda. | we note the existence of a "partially cis-acting" regulatory protein of bacteriophage lambda: the product of the phage q gene. we suggest that there may be a complete spectrum from "all cis" to "all trans" for such regulatory proteins. this behavior might arise because a dna-binding protein either acts at a nearby (cis) site soon after synthesis or becomes "lost" for its trans activity on another genome through nonspecific interactions with dna. our proposed explanation provides one evolutionary ... | 1976 | 773751 |
| directed integration of bacteriophage lambda in an f lac transposition hfr strain of escherichia coli: isolation and characterization of specialized transducing phages for the phenylalanine and tyrosine operons. | 1976 | 775105 | |
| lack of a unique termination site for the first round of bacteriophage lambda dna replication. | 1976 | 775112 | |
| lysogenization of escherichia coli by bacteriophage lambda: complementary activity of the host's dna polymerase i and ligase and bacteriophage replication proteins q and p. | when bacteriophage lambda dna replication is blocked by mutation in phage genes o or p, the efficiency of lysogenization drops to a very low value unless high multiplicities of infecting phage are used. our results show that even at high multiplicity, lambda o or p mutants cannot efficiently lysogenize some hosts that are defective in either dna polymerase i or dna ligase. covalent closure of infecting dna molecules, a preliminary step for insertion according to campbell's model and an obvious c ... | 1976 | 775126 |
| a bacterial rna polymerase mutant that renders lambda growth independent of the n and cro functions at 42 degrees c. | we describe a bacterial rna polymerase mutation, rif 501, which confers rifampicin resistance and thermosensitivity to e. coli k 12. the purified rna polymerase enzyme from rif 501 bacteria shows increased heatsensitivity in vitro at 51 degrees c. however, in vivo, at 42 degrees c the non-permissive temperature, mutant bacteria continue to grow and to synthesize rna for 90 min. on a lawn of the mutant bacteria, at 40-41 degrees c, phage lambda forms clear plaques (lyca phenotype); this is probab ... | 1976 | 775309 |
| expression of flagellar genes carried by bacteriophage lambda. | 1976 | 775345 | |
| functional genetic expression of eukaryotic dna in escherichia coli. | we have isolated a segment of dna from the eukaryote saccharomyces cerevisiae (baker's yeast) as a viable molecular hybrid of bacteriophage lambda dna which, when integrated into the chromosome of an e. coli histidine auxotroph, allows this bacterium to grow in the absence of histidine. the nonrevertable, histidine auxotroph lacks the enzymatic activity of imidazole glycerol phosphate (igp) dehydratase (ec 4.2.1.19). from genetic experiments, we conclude that expression of the segment of yeast d ... | 1976 | 775490 |
| role of s gene of bacteriophage lambda in host lysis. | 1976 | 776186 | |
| maltose transport in escherichia coli k12. a comparison of transport kinetics in wild-type and lambda-resistant mutants as measured by fluorescence quenching. | the kinetic parameters for the maltose transport system in escherichia coli k12 were determined with maltose and maltotriose as substrates. the system exhibits an apparent km of 1 mum for maltose and 2 mum for maltotriose. the v of entry was determined as 2.0 and 1.1 nmol substrate/min per 10(8) cells. mutations in lamb, the structural gene for the receptor protein of phage lambda, increased the km for maltose transport by a factor of 100-500 without influencing the maximal rate of transport. ma ... | 1976 | 776623 |
| a mutant of escherichia coli that prevents growth of phage lambda and is bypassed by lambda mutants in a nonessential region of the genome. | 1976 | 779235 | |
| a genetic analysis of bacteriophage lambda head assembly. | 1976 | 779236 | |
| new att mutants of phage lambda. | 1976 | 779238 | |
| the red plaque test: a rapid method for identification of excision defective variants of bacteriophage lambda. | 1976 | 779239 | |
| physical mapping of coliphage lambda att2. | 1976 | 779246 | |
| attempts to purify a membrane attached chromoid of bacteriophage lambda. | using methods which proved successful for the isolation of e. coli chromosome in a folded form (the e. coli chromoid), we have attempted to purity the "native" form of bacteriophage gamma chromosome from gamma infected cells. upon sedimentation of lysates we find that phage dna separates into two fractions, one of which cosediments with the bacterial chromoid ; the other sediments nearer to the top of gradient. both fractions probably contain membrane-bound phage dna, and both support the in viv ... | 1976 | 779853 |
| mutant of escherichia coli that instantaneously loses the ability to adsorb lambda bacteriophage upon exposure to high temperature. | lad (lambda adsorption), an escherichia coli mutant that loses the ability to adsorb lambda phage immediately after a shift to high temperature (e.g., 42 c), was isolated. this property for phage adsorption is irreversible and has been observed with phage lambda and 21 but not with phages 434, phi 170, and phi 80. a crude receptor preparation, extracted from lad cells will cholate-ethylenediaminetetraacetic acid by the procedure of randall-hazelbauer and schwartz (1973), inactivated the phage la ... | 1976 | 780336 |
| morphogenesis of bacteriophage lambda: electron microscopy of thin sections. | 1976 | 781268 | |
| the circle mode of replication of bacteriophage lambda: the role of covalently closed templates and the formation of mixed catenated dimers. | 1976 | 781278 | |
| transposition and fusion of the lac genes to selected promoters in escherichia coli using bacteriophage lambda and mu. | 1976 | 781293 | |
| lethal lysogenization by coliphage lambda. | 1976 | 782020 | |
| the effect of 5-bromouracil on recombination of phage lambda. | 1976 | 782022 | |
| second-site mutations in capr (lon) strains of escherichia coli k-12 that prevent radiation sensitivity and allow bacteriophage lambda to lysogenize. | capr (lon) mutants of escherichia coli k-12 are mucoid and sensitive to ultraviolet (uv) and x-ray radiation as well as to nitrofurantoin. the mutants form filaments after exposure to these agents. capr mutants are also conditionally lethal since they die when plated on complex medium even without uv treatment; this phenomenon is designated "complex medium-induced killing". furthermore, capr mutants are poorly lysogenized by bacteriophage lambda. second-site revertants were isolated by plating o ... | 1976 | 783136 |
| role of the bacterial and phage recombination systems and of dna replication in genetic recombination of uv-irradiated phage lambda. | in this paper are studied in e. coli k12 the influence of the bacterial rec and phage mu red recombination systems on the rescue of the o plus gene from the prophage by a superinfecting o minus phage, uv irradiated or not. in the absence of uv irradiation the red system produces more recombinants than does the rec system, and its action requires dna replication. the presence of uv lesions in the mu dna facilitates the action of the rec system, which is more efficient in this instance than the re ... | 1976 | 785209 |
| control of ci gene expression in bacteriophage lambda imm434, studied in an immunity/trp fusion made in vitro. | the trp genes of a lambda imm434 trp-transducing phage have been fused to the immunity region by deletion, in vitro, of the dna between two targets for the restriction enzyme r.ecori. the resulting phage has been used to study the control of expression of the ci gene in vivo. the constitutive rate of expression of the ci gene is between 2 and 5% of the maximally stimulated rate. the products of the cii and ciii genes enhance expression of ci on infection of a sensitive host. the requirement for ... | 1976 | 785219 |
| the construction in vitro of transducing derivatives of phage lambda. | methods are described for the construction of plaque-forming, transducing derivatives of phage lambda, using appropirate receptor genomes and fragments of dna generated by the restriction enzymes endo r.ecori and endo r.hindiii. the general properties of the transducing derivatives are described and discussed. plaque-forming phages carrying the e. coli trp, his, cysb, thya, supd, supe, sup f, hsd, tna and lig genes have been isolated. | 1976 | 785220 |
| n-terminal sequence of phage lambda repressor. | lambda repressor was purified from an e. coli strain which produces 150 times more lambda repressor than a single lysogen. the sequence of the fifty n-terminal residues was determined by automated edman degradation. it contains 43% of all arginine and lysine residues of the chain and constitutes according to the genetic data of oppenheim et al. (1975) a substantial part of the operator-dna-binding site of the repressor. | 1976 | 785222 |
| phenotypic instability in a tif-1 mutant of escherichia coli. ii. recessiveness of the tif-1 mutation. | merodiploids of the type tif-1/f'tif+, constructed in e. coli k12 strain t44(lambda), show that the tif-1 mutation is recessive with respect to induction of phage lambda and thermolability. an additional manifestation of tif-1 expression is increased tolerance to low levels of streptomycin (sm) and chloramphenicol (cm) and this, too, is abolished in the merodiploids. | 1976 | 785227 |
| regional replication of the bacterial chromosome induced by derepression of prophage lambda. ii. direction and origin. | we have demonstrated previously by dna-dna hybridization that induction of lambda phage with wild type o and p genes results in an increase of bacterial dna in the chromosomal region adjacent to the left of the prophage; is a segment between gal and attlambda (gal dna) (imae and fukasawa, 1970). evidence is presented in this report that such an increase of bacterial dna is also seen in the region to the right of the prophage; a segment between bio and attlambda (bio dna). we postulate therefore ... | 1976 | 785228 |
| a class of rifr rna polymerase mutations that interferes with the expression of coliphage lambda late gene. | 1976 | 785804 | |
| isolation of bacteriophage lambda containing yeast ribosomal rna genes: screening by in situ rna hybridization to plaques. | we have developed an in situ hybridization technique which can be used to screen large numbers of hybrid bacteriophage for the presence of a particular inserted dna sequence. plaques of hybrid phage are formed on e. coli lawns on nitrocellulose filters, and their dna is released, denatured, and fixed directly on the filters for hybridization to radioactive rna probes. we have used this technique to isolate a number of hybrid bacteriophage lambda which contain ecorl restriction fragments of the r ... | 1976 | 786462 |
| use of a sequence-specific dna-binding ligand to probe the environments of ecori restriction endonuclease cleavage sites. | the dnas of bacteriophage lambda and adenovirus were incubated with the sequence-specific dna-binding ligand 6,4'-diamidino-2-phenylindole. digestion of the ligand-dna complexes with ecori nuclease and subsequent agarose gel electrophoresis demonstrated that the ligand inhibited nuclease activity at some sites, but not at others. the results suggest that diamidino-2-phynylindole can be used to probe the immediate environments of the ecori cleavage sites. | 1976 | 786629 |
| expression of the guanine operon of escherichia coli as analyzed by bacteriophage lambda induced mutations. | studies were made on two guanine-requiring strains of escherichia coli isolated independently as a result of insertion of prophage gamma into one of the structural genes of the guanine operon. these mutants do not exhibit any detectable guab function but express the guaa function constitutively at a low level, presumably due to transcription from the pi promoter on the prophage. various types of plaque-forming gua-transducing phages were generated from these lysogens. the approximate location an ... | 1976 | 787758 |
| [bacteriophage lambda head assembly]. | 1976 | 787945 | |
| specialized transduction of colicin e1 dna in escherichia coli k-12. | genetic studies were made on e. coli k-12 tm96, which carries recombinant molecules constructed by in vitro combination of colicin e1 dna and a dna fragment of e. coli for guanine synthesis derived from transducing phage. the recombinant molecules existed as stable plasmids within the cell and contained genes for colicin e1 immunity and the guaa enzyme (xanthosine 5'-monophosphate aminase) together with a part of the lambda genome, r through j: (r-a-f-j)+. a block of the lambda genome, int throu ... | 1976 | 787989 |
| new types of escherichia coli recombination-deficient mutants. | a set of escherichia coli mutants deficient in intramolecular recombination and different from those previously found is described. all have temperature-sensitive lethal mutations. the mutants have been characterized with respect to the following properties: the pap phenotype, deoxyribonucleic acid synthesis, sensitivity to ultraviolet light, ability to support the growth of phage lambda, filament formation, and mutation frequency. | 1976 | 789362 |
| efficient suppression of the requirement for n function of bacteriophage lambda by a rho-defective e.coli sua mutant. | the e. coli sua mutant (t82), which is a suppressor of polarity by virtue of its impaired transcription termination factor (rho) activity, is shown to be an efficient suppressor of lambdan- mutants. the relief of the n requirement by this host is reflected in a substantial restoration of growth and n-dependent beta-galactosidase expression as well as in a partial relief of polarity of n-defective phages. | 1976 | 790156 |
| specificity of polarity suppression in e. coli: correction of defects in gene n, but not in gene q, of phage lambda. | the bacterial mutation psua1, known as (sua) a polarity suppressor, partially relieves all n defects in bacteriophage lambda growth. no evidence is found that psua1 relieves q defects in lambda growth. specific mechanisms of action by the n and q gene products are discussed. the psua1 mutation was also found to suppress is1 type but not is2 type insertion mutations in lambda. | 1976 | 790157 |
| maturation of a single lambda phage particle from a dimeric circular lambda dna. | 1976 | 790755 | |
| n-ethylmaleimide and the induction of phage lambda. | 1976 | 790756 | |
| isolation of lambda prophage mutants defective in structural genes: their use for the study of bacteriophage morphogenesis. | mutants of coliphage lambda defective in structural genes were isolated and characterized. the isolation method consisted in lysogenizing bacteria with mutagenized phage and testing for inability to form plaques after heat induction. the mutants were propagated as prophages in the lysogens. mutants in the region of the tail-genes u, v, g and h were enriched for by a selection method based on recombination and complementation with known mutants, and they were mapped by deletion mapping with newly ... | 1976 | 792680 |
| a transducing bacteriophage lambda carrying the structural gene for elongation factor ts. | a specialized transducing bacteriophage lambdadpolcdap d-9 has been isolated that carries the structural gene for ef-ts1 (tsf). the presence of ef-ts among the proteins synthesized under the direction of this phage in uvl-inactivated cells has been detected by two-dimensional gel electrophoresis and has been verified by antibody precipitation. in an induced lysogen of this phage the relative rate of synthesis of ef-ts is increased 4-fold. evidence is presented which suggest that the structural g ... | 1976 | 792684 |
| [competency of escherichia coli cells. iv. effect of freezing--thawing on the formation of competency in escherichia coli cells in the presence of ca++ ions]. | the paper is initiated in the aim to use the effect of freezing-thawing in the system of intact escherichia coli cells treated with ca++ ions to increase the transfection efficiency. it is demonstrated that freezing-thawing of ca++ treated cells increases the transfection indices of lambda phage dna for e. coli hfr clone with low transfection indices in 20-30 times, and for the strain of e. coli x7026 of high competence-in 5 times. freezing-thawing efficiently increased the transfection only in ... | 1976 | 793933 |