Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| mapping missense and nonsense mutation in gene ci of bacteriophage lambda: marker effects. | amber and missense mutations in gene ci of bacteriophage lambda were mapped by reciprocal four-factor crosses, selecting recombinants between the outside markers (n amber and o amber). distances between ci missense mutations were additive. several ci amber mutants recombined with other ci mutations with a higher frequency than expected from the map location. multiple exchanges in the n-o region occurred at a frequency greater than expected by chance. this "high negative interference" was especia ... | 1976 | 794694 |
| cloning of all ecori fragments from phage lambda in e.coli. | 1976 | 794729 | |
| induction of sigma factor synthesis in escherichia coli by the n gene product of bacteriophage lambda. | thermoinduction of cells of e. coli carrying prophage lambdaci857 within the bfe gene brings about not only "escape synthesis" of core subunits of the dna-dependent rna polymerase (rna nucleotidyltransferase, nucleosidetriphosphate:rna nucleotidyltransferase, ec 2-7-7-6), but also a striking stimulation of sigma factor synthesis. the latter phenomenon, termed sigma induction, is generally observed after lambda phage infection or prophage induction. a series of experiments with various bacterial ... | 1976 | 794877 |
| the yield of radiation-induced dna single-strand breaks in escherichia coli and superinfecting phage lambda at different dose rates. repair of strand breaks in different buffers. | 1976 | 794917 | |
| suppressible mutations in the cro gene of bacteriophage lambda. | 1976 | 795138 | |
| physicochomecial studies on interactions between dna and rna polymerase. isolation and mapping of a t7 dna fragment containing the early promoters for escherichia coli rna polymerase. | the cleavage sites in the early promoter region of coliphage t7 have been mapped for four restriction enzymes. they are, from the left end in base pairs, 1100 and 740 for hinf; 680, 320, 530, 240, 77, and 67 for hind ii; 620 and 530 for hpa ii; 790 for alu i. the nucleotide sequence between the hind ii site at 680 base pairs from the left end and the hinf site at 740 base pairs from the left end has been determined, from which the start point of the promoter a3 is located at 720 base pairs from ... | 1976 | 795461 |
| [physical mapping of products of phage lambda dna hydrolysis by serratia marcescens restriction endonuclease]. | 1976 | 795624 | |
| cell envelope proteins involved in the transport of maltose and sn-glycerol-3-phosphate in escherichia coli. | two types of proteins are discussed in their role of facilitating the transport of maltose and sn-glycerol-3-phosphate in e. coli. the first protein is the receptor for phage lambda, known to be an outer membrane protein. by facilitating the diffusion of maltose and the higher maltodextrins through the outer membrane the effect of the lambda receptor is to decrease the km of the transport system without influencing the vmax of substrate flux. the second protein is a periplasmic protein that is i ... | 1976 | 795812 |
| overproduction of phage lambda repressor under control of the lac promotor of escherichia coli. | the gene coding for bacteriophage lambda repressor (ci gene) has been fused to the lac operon of escherichia coli. in some of the fusions lambda repressor synthesis can be controlled by the lac operator and promoter. upon induction of the lac operon the amount of lambda repressor is increased by a factor of 7 over that found in a single lysogen. in combination with the polarity suppressor sua the induction factor rises to 20. transducing phages of one fusion were constructed. after thermal induc ... | 1976 | 796661 |
| a map of the restriction targets in yeast 2 micron plasmid dna cloned on bacteriophage lambda. | the 2 micron circular dna from s. cerevisiae has been cloned on bacteriophage lambda. the two forms of circular dna which exist in equilibrium due to recombination between inverted repeat sequences were separated as stable clones, and a map of targets for restriction endonucleases ecori, hindiii and hpai was constructed. the circular dnas isolated from a particular oligomycin resistant strain and its parent oligomycin snesitive strain were compared by restriction endonuclease analysis, and no di ... | 1976 | 796664 |
| identity of a gene responsible for suppression of aminoacyl-trna synthetase mutations with rpst, the structural gene for ribosomal protein s20. | sepcialized transducing lines of phage lambda carrying segments between thr and car from the e. coli chromosome have been isolated. with help of these phages it has been shown that the gene sups20 (böck et al., 1974) corresponds to rpst, the structural gene for ribosomal protein s20. | 1976 | 796681 |
| [morphogenesis of the tail of bacteriophage lambda (author's transl)]. | 1976 | 796887 | |
| lysogenization by bacteriophage lambda iv inhibition of phage dna synthesis by the products of genes cii and ciii. | in direct measurements of phage lambda dna synthesis, we have detected an inhibition caused by the cii and ciii gene products. this inhibition was more clearly observed when p amber phages were grown in a permissive host, presumably because of the limitation in dna synthesis due to uncomplete suppression. the inhibition takes place in cells infected at high multiplicity, but not in cells infected at low multiplicity. to explain these findings, we propose a model in which the bacterial population ... | 1976 | 797399 |
| [new mutations in the early stage of phage lambda]. | 1976 | 798250 | |
| effect of change in structure of cohesive ends on aggregating ability and biological activity of bacteriophage lambda dna. | the effect of different types of buildup of the cohesive ends on the ability of phage lambda dna molecules to form cyclic and concatemeric forms and on their biological activity in two infection systems--transfection and transformation--was investigated with the aid of e. coli dna polymerase. a change in the structure of the cohesive ends leads to a change in the aggregating ability of the phage lambda dna molecules up to an almost complete loss of this ability. the infectious activity of phage ... | 1976 | 799259 |
| propagation in e. coli of bacteriophage lambda with integrated fragments of adenovirus 2 dna. | hybrid genomes of bacteriophage lambda with integrated fragments of adenovirus type 2 (ad2) dna have been constructed in vitro and propagated in e. coli. dna from a derivative of bacteriophage lambdaplac5 (rambach and tiollais, 1974) was used as a vector. the two fragments of the vector dna contain all the essential genes for the replication of the lambda dna but are too short to be encapsidated. insertion of dna is therefore essential for plaque formation which constitutes a selection method fo ... | 1976 | 802391 |
| in vitro construction of bacteriophage lambda and plasmid dna molecules containing dna fragments from bacteriophage t4. | restriction endonucleases ecori and hindiii generated fragments of t4 cytosine-containing dna were inserted into bacteriophage vector lambdagtsuiii and plasmid vectors pmb9 and pbr313. resulting clones were screened for hybridization with 32p labeled t4 trna. recombinant bacteriophages and plasmids were isolated which contained a t4 fragment coding for t4 rna species 1 and 2 and t4 trna arg. selected lambda-t4 hybrid bacteriophages were grown to high titer and their dna analyzed by gel electroph ... | 1976 | 802392 |
| [identification of partial hydrolysis products of lambda bacteriophage dna by restriction endonuclease ecori]. | the relationship between the electrophoretic mobility of double stranded dna fragments electrophoresed in agarose gel and their molecular weights within the range from 1.10(6) to 8.10(7) daltons and agarose concentration 0.3--2.0% has been studied. partial hydrolysis products of lambda phage dna obtained by restriction endonuclease ecori have been separated. partial hydrolysis products have been identified by determining the fragments of full cleavage as well as by genetic methods using a system ... | 1976 | 802774 |
| evidence for common binding sites for ferrichrome compounds and bacteriophage phi 80 in the cell envelope of escherichia coli. | mutants ton a and ton b of escherichia coli k12, known to be resistant to bacteriophage phi80, were found to be insensitive as well to albomycin, an analogue of the specific siderochrome ferrichrome. ferrichrome at micromolar concentrations strongly inhibited plaque production by phi80. preincubation with ferrichrome did not inactivate the phage. at a concentration at which ferrichrome allowed 90% inhibition of plaque formation, the chromium analogue of ferrichrome showed no detectable activity. ... | 1975 | 803957 |
| elements involved in site-specific recombination in bacteriophage lambda. | 1975 | 807737 | |
| isolation of coliphage lambda ghosts able to adsorb onto bacterial cells. | we have examined three methods of lambda ghost production, starting with the [3h]leucine-labelled phage, purified by cscl density gradient sedimentation. ghosts obtained by the osmotic shock or by incubation in 5 m licl do not adsorb on bacteria. ghosts obtained by the treatment with the chelating agent edta and purified by cscl density gradient sedimentation possess well preserved adsorption properties and are virtually free of dna and infectious phage particles. | 1975 | 809058 |
| putrescine and certain polyamines can inhibit dna injection from bacteriophage lambda. | 1975 | 809592 | |
| 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 | |
| identification of the site of interruption in relaxed circles producing during bacteriophage lambda dna circle replication. | the dna that accumulates in the lambda infection restricted to the early (circular) stage of replication consists of approximately two-thirds covalently closed circles and one-third relaxed circles bearing a single interruption in either strand of the duplex. the latter molecules are presumed to be a unique class in that the interruption is not repairable by dna polymerase and ligase. preferential radioisotopic labeling of the region immediately adjacent to the interruption, followed by hybridiz ... | 1977 | 833943 |
| purification and characterization of the major protein and the terminator protein of the bacteriophage lambda tail. | 1977 | 835226 | |
| the isolation of restriction fragments containing the att site of bacteriophage lambda. | 1977 | 835230 | |
| packaging of the bacteriophage lambda chromosome: effect of chromosome length. | 1977 | 841861 | |
| charon phages: safer derivatives of bacteriophage lambda for dna cloning. | the charon lambda bacteriophages have been developed as vectors for cloning. their construction incorporates mutations that make them simple to use and also greatly increases their safety for the biological containment of cloned recombinant dna. three of the charon vector phages, 3a, 4a, and 16a, have been certified for use as ek2 vector-host systems, when propagated in bulk in a special bacterial host, dp50supf. we present here some of the data on which the safety of these systems was evaluated ... | 1977 | 847462 |
| suppression of a pm mutant by the sar mutation for the synthesis of repressor by bacteriophage lambda. | 1977 | 853519 | |
| genetic effects of photoadducts and photocross-links in the dna of phage lambda exposed to 360 nm light and tri-methylpsoralen or khellin. | the furocoumarin, 4,5',8-trimethylpsoralen, sensitizes cells and viruses to 360 nm light, producing cross-links and monoadducts in their dna. the furanochromone khellin is a less effective sensitizing agent than psoralen, but has been found to induce cross-links and adducts in dna also. the number of cross-links increases as the square of the time of exposure to light. we found that greater fluences were required for khellin than for psoralen, possibly because of the less favorable angle of the ... | 1977 | 856276 |
| a genetic analysis of the att-int-xis region of coliphage lambda. | 1977 | 859185 | |
| studies on an in vitro system for the packaging and maturation of phage lambda dna. | 1977 | 860404 | |
| early events in the in vitro packaging of bacteriophage lambda dna. | 1977 | 860405 | |
| regulation of protein synthesis in bacteriophage lambda. restoration of gene expression in lambda n-strains by mutations in the cro gene. | 1977 | 867830 | |
| interaction of cii, ciii, and cro gene products in the regulation of early and late functions of phage lambda. | 1977 | 867831 | |
| the product on gene p of coliphage lambda. | 1977 | 867832 | |
| completed dna sequences and organization of repressor-binding sites in the operators of phage lambda. | 1977 | 875019 | |
| independence of gene n and tof functions of bacteriophage lambda. | 1977 | 875037 | |
| rolling circle replicative structure of bacteriophage lambda dna in a recombination deficient system. | rolling-circle replicating structures which represent late stage lambda dna replication can be detected among intracellular phage lambda dna molecules under recombination deficient conditions as well as in wild-type infections. furthermore, if initiation of lambda replication is delayed until the late stage of lambda infection, then nearly all replicating molecules are rolling-circle, even in the first round. thus neither genetic recombination nor termination of a round of replication are requir ... | 1977 | 876025 |
| transcription of a mammalian sequence under phage lambda control. | 1977 | 876387 | |
| a map of the cleavage sites for endonuclease avai in the chromosome of bacteriophage lambda. | the linear order of nine fragments generated by the action of endonuclease avai on the dna of bacteriophage lambda was determined from the altered fragmentation patterns of bacteriophages containing known deletions and of hybrids of bacteriophages lambda and phi80. digestion of 5'-terminally 32p-labelled bacteriophage-lambda dna was used to identify the terminal fragments. measurement of relative fragment lengths permitted rough mapping of the endonuclease-avai cleavage sites relative to the end ... | 1977 | 880215 |
| site-specific recombination in bacteriophage lambda. | 1977 | 886614 | |
| cell free synthesis of bacteriophage lambda replication proteins. | 1977 | 891979 | |
| the essential role of the cro gene in lytic development by bacteriophage lambda. | 1977 | 898664 | |
| synthesis and biological activity of a lambda pseudo operator. | the chemical and enzymatic syntheses of bacteriophage lambda pseudo operator dna are described. the 17 base-paired duplex contains the dna which has been proposed as the binding site for ci repressor protein. the synthetic duplex is twofold symmetric and represents the best possible nucleotide summation of the six proposed operator sites in the leftward and rightward operators. however, it does not correspond exactly to any single proposed operator sequence. the chemical synthesis includes the d ... | 1977 | 901770 |
| dna sequence at the end of the ci gene in bacteriophage lambda. | the nucleotide sequence of 57 base pairs near the end of the ci gene in phage lambda is presented. this sequence was determined by direct sequencing techniques and includes the codons for 11 carboxyterminal aminoacids of the ci product, the lambda repressor. the sequence reveals that the ci gene, which has recently been shown to have a unique initiation region, is terminated by a uga codon. a gug triplet, which could act as a translation start signal for the rex gene occurs 8 base pairs beyond t ... | 1977 | 909767 |
| protection of particular endonuclease r. hind iii cleavage sites by distamycin a, propyl-distamycin and netropsin. | it is shown that three related antibiotics, distamycin a, propyl-distamycin and netropsin, can protect certain endo r.hind iii cleavage sites from attack by endonuclease, giving rise, after endo r.hind iii digestion, to larger dna fragments. bacteriophage lambda dna has six recognition sites for hind iii enzyme. three of these sites: shind iii 2, 3 and 6 can be protected from nuclease action by all the antibiotics used. propyl-distamycin protects partly shind iii 5, too. netropsin protects partl ... | 1977 | 909774 |
| a ribosome binding site from the pr rna of bacteriophage lambda. | 1977 | 915942 | |
| simple method of purification of bacteriophage lambda by hydroxyapatite column chromatography. | 1977 | 924490 | |
| rapid method for the purification of bacteriophage lambda by gel filtration. | 1977 | 924534 | |
| mapping of restriction sites in the attachment site region of bacteriophage lambda. | a find structure map of the ecori fragment containing the lambda attachment-site region has been constructed. 38 different restriction endonucleases have been employed and 170 sites located in this fragment. in addition, sites in adjacent regions have been determined for several enzymes. complete cleavage maps of the entire lambda genome have been obtained for endonucleases bglii, blui, kpni, saci, sacii, sali and xbai. the strategy employed for mapping included comparison of deletion and substi ... | 1977 | 927438 |
| construction of chimeric phages and plasmids containing the origin of replication of bacteriophage lambda. | segments of the replication control region of bacteriophage lambda (lambda) and lambda mutants defective in replication were attached in vitro to the phi80 phage vector charon 3 and to the plasmid vector mini col el (pvh51). the chimeric phages and plasmids have been used to localize the origin of lambda dna replication and to facilitate a structural analysis of the lambda replicator. | 1977 | 929185 |
| genetic structure of the replication origin of bacteriophage lambda. | a fragment of bacteriophage lambda dna produced by the restriction endonuclease eco ri and extending from the immunity region to a point inside gene o is found to have a fully functional origin of replication. seven ori- mutations of lambda cluster in a small region just to the left of the eco ri cleavage site which defines the right end of this fragment. these mutations lie within gene o. | 1977 | 929186 |
| physical structure of the replication origin of bacteriophage lambda. | the nucleotide sequence of part of the replication region of wild-type bacteriophage lambda and of four mutants defective in the origin of dna replication (ori-) has been determined. three of the ori- mutations are small deletions, and one is a transversion. the sequence of the origin region, defined by these mutations, contains a number of unusual features. | 1977 | 929187 |
| deletion mutations and the replication of dna in bacteriophage lambda. | 1977 | 929978 | |
| 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 |
| isolation of the bacteriophage lambda a-gene protein. | an in vitro assay for measuring the activity of the phage lambda a-gene product has been developed. the assay is based on the observation that a-donor extracts complement a minus extracts for packaging of exogenous immature lambda dna into phage particles. a partial purification of the a-gene product activity using this assay is presented. a method is suggested by which this a protein-dependent in vitro system might be manipulated to analyze the mechanism of reforming the lambda cohesive termini ... | 1975 | 1054839 |
| integrative recombination of bacteriophage lambda dna in vitro. | an in vitro system for the production of integrative recombinant dna of bacteriophage lambda is described. the in vitro recombination mimics the in vivo integration of viral dna into host dna in its requirement for int gene product, for the presence of a thermolabile component, and for the limitation of the recombination to a pair of specialized sites (attachment sites) on the dna. the enzymes are extracted from escherichia coli containing phage lambda gene products. the substrate is the dna fro ... | 1975 | 1055366 |
| nucleotide sequence of the rightward operator of phage lambda. | the sequence of 72 base pairs of the rightward operator (o-r) of bacteriophage lambda is presented as determined with simple and rapid methods for direct dna sequencing. the sequence of an operator mutant is also described. the methods are of general use in sequencing dna fragments with unique 5' ends up to 50 base pairs in length. previous experiments have shown that this operator contains multiple sites recognized by the lambda phage repressor. we believe we have identified three of these site ... | 1975 | 1055375 |
| repression and autogenous stimulation in vitro by bacteriophage lambda repressor. | purified lambda repressor protein is shown to reduce the lambda dna-directed synthesis of proteins in vitro as determined both by net amino-acid incorporation and by analysis of specific lambda-coded proteins resolved by sodium dodecyl sulfate/polyacrylamide slab gel electrophoresis. by means of different lambda dna templates carrying deletion and point mutations in the operators o-l or o-r, it has been possible to demonstrate repression of the synthesis of two classes of lambda proteins. the sy ... | 1975 | 1055378 |
| transcription termination and late control in phage lambda. | a transcription termination site occurs between the promoter for late gene expression of bacteriophage lambda and the late genes themselves. it is proposed that the lambda q gene product controls late gene expression by over-coming this termination barrier. | 1975 | 1059112 |
| transposition of r factor genes to bacteriophage lambda. | transpositions of segments of r factor (antibiotic resistance plasmids) to bacteriophage lambda have been selected and characterized. cells of escherichia coli harboring r factors that determine kanamycin resistance were infected with phage lambda, and lambdakan transducing lines were obtained. each of the three examined is unusual when compared to lambda transducing phages containing e. coli chromosomal genes: the kan insertions (a) occur at several sites, each well removed from the integration ... | 1975 | 1059152 |
| acquisition of a determinant for chloramphenicol resistance by coliphage lambda. | a determinanat for chloramphenicol resistance, cam, initially detected on a resistance transfer factor (rtf) and since transferred to phage p1, may be acquired from p1 by coliphage lambda. lambdapcam are obtained when a lambda prophage is induced in bacteria which also harbor p1 cam prophage. lambdacam formation is not dependent upon host rec or lambda red recombination functions. electron microscopic heteroduplex analysis shows that the cam locus in two lambdapcams is a 5% addition of dna in th ... | 1975 | 1061090 |
| 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 |