Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| proposed mechanism of bacteriophage lambda induction: acquisition of binding sites for lambda repressor by dna of the host. | interference with the in vitro binding of lambda phage repressor to lambda operator dna was observed when escherichia coli dna containing the following lesions was present in the reaction mixture: (a) dna with single-strand breaks from pancreatic dnase (nicked dna); (b) dna isolated from thymine-straved cells; (c) dna from ultraviolet-treated cells; (d) dna of mitomycin-treated cells; and (e) dna from a temperature-sensitive ligase mutant after 1 hr at 42 degrees. normal e. coli dna did not inte ... | 1975 | 1098048 |
| strand breakage of coliphage lambda dna supercoils in infected lysogens. i. genetic and biochemical evidence for two types of nicking processes. | 1975 | 1098274 | |
| the kil gene of bacteriophage lambda. | 1975 | 1098278 | |
| host mutants resistant to phage lambda killing. | 1975 | 1098279 | |
| regulation of early protein synthesis in bacteriophage lambda. | 1975 | 1098280 | |
| isolation of specialized transducing bacteriophage lambda carrying genes of the l-arabinose operon of escherichia coli b/r. | a heat-inducible lysis-defective phage lambda (lambdaci857s7) has been integrated at multiple sites within the l-arabinose region (aracoibad) of a strain of escherichia coli k-12 deleted for the normal lambda attachment site (lambdaattdelta). the lambda phage has become integrated with opposite orientations at two different loci within the aratb gene and with the "normal" orientation (clockwise n-ra-j) at a single site in the arac gene. the burst size, spontaneous-curing frequencies, and number ... | 1975 | 1099071 |
| electron microscopic study of the repressor of bacteriophage lambda and its interaction with operator dna. | 1975 | 1099211 | |
| the nature and origin of a class of essential gene substitutions in bacteriophage lambda. | 1975 | 1099781 | |
| maltose transport in escherichia coli k-12: involvement of the bacteriophage lambda receptor. | mutants affected in lamb, the structural gene for phage lambda receptor, are unable to utilize maltose when it is present at low concentrations (less than or equal 10 mum). during growth in a chemostat at limiting maltose concentrations, the lamb mutants tested were selected against in the presence of the wild-type strain. transport studies demonstrate that most lamb mutants have deficient maltose transport capacities at low maltose concentrations. when antibodies against purified phage lambda r ... | 1975 | 1100596 |
| role of the receptor for bacteriophage lambda in the functioning of the maltose chemoreceptor of escherichia coli. | chemotaxis towards maltose is specifically defective in many strains of escherichia coli carrying mutations affecting lamb, the gene coding for the outer membrane receptor for bacteriophage lambda. however, with one exception, the most extreme effect of lamb mutants on the maltose response as determined in the capillary assay is a shift to higher sugar concentrations and a reduction in the number of bacteria accumulated to about 25% of the wild-type level. the severity of the taxis defect is str ... | 1975 | 1100597 |
| indirect mutagenesis in phage lambda by ultraviolet preirradiation of host bacteria. | 1975 | 1100853 | |
| extensive segments of the escherichia coli k12 chromosome in proteus mirabilis diploids. | various escherichia coli k12 hfr donors transfer at low frequency portions of the e. coli genome to proteus mirabilis. by remating such proteus hybrids with the same or a different e. coli hfr strain, other genetic characters could be added to yield diploid proteus hybrids which contained more than 30 percent of the e. coli genome. the extent of the e. coli genetic material in these unstable proteus diploid hybrids included segments with the following selected markers: gal, lac, ara, mel, mtl, a ... | 1975 | 1101034 |
| [e. coli mutanic produced by the insertion of bacteriophage lambda dna (author's transl)]. | 1975 | 1101309 | |
| synthesis and degradation of early mrna in lambda phage. | using two different escherichia coli mutants defective in elongation factors efg and efts required for peptide synthesis, lambda phage with or without a tof mutation was analysed for synthesis of early mrna by dna-rna hybridization technique. (1) in cp78g carrying temperature-sensitive elongation factor g, shift-up to high temperature (41 degrees c) in the middle of phage infection did not affect early mrna synthesis with lambdatof+ phage but did inhibit it with lambdatof- phage. (2) in hak88 ca ... | 1975 | 1101966 |
| tandem genetic duplications in phage lambda. iii. the frequency of duplication mutants in two derivatives of phage lambda is independent of known recombination systems. | 1975 | 1102698 | |
| processing of bacteriophage lambda dna during its assembly into heads. | 1975 | 1102699 | |
| dna packaging steps in bacteriophage lambda head assembly. | 1975 | 1102700 | |
| assembly of bacteriophage lambda heads: protein processing and its genetic control in petit lambda assembly. | 1975 | 1102701 | |
| studies on the cleavage of bacteriophage lambda dna with ecori restriction endonuclease. | 1975 | 1102702 | |
| replication of bacteriophage lambda dna: in vivo studies of the interaction between the viral gamma protein and the host recbc dnaase. | 1975 | 1102714 | |
| further structural and functional analogies between the repressor regions of phages p22 and lambda. | mutants of p22 which have been located in the c2 repressor gene were examined. the most rightward "c2 mutation" was found to define a site that is necessary only for the establishment and not for the maintenance of repressor synthesis. we conclude that this site c27 is an analog of cy mutants in phage lambda which define a promotor for repression establishment (pre). the k5 mutation of p22 maps between c27 and all other c2 mutants. examination of its biological behavior and direct measurement of ... | 1975 | 1102926 |
| visualization of a novel junction in bacteriophage lambda dna. | at early times after infection of a reca derivative of escherichia coli with lambdab221c126red270a42 phage, a low but significant proportion of intracellular lambda molecules show a novel junction. these junctions are also present, although in reduced numbers, in a lysate obtained at late times after infection of a reca+ host with lambdaciiciii phage. fine structure and denaturation mapping analyses showed that these junctions occur at homologous positions and that they are compatible with the o ... | 1975 | 1103134 |
| in vitro construction of bacteriophage lambda carrying segments of the escherichia coli chromosome: selection of hybrids containing the gene for dna ligase. | dna from lambdagt-lambdab bacteriophage was cleaved with ecori endonuclease and fragments from ecori-digested e. coli dna were inserted. this dna was used to infect e. coli, and phages containing the gene for dna ligase were isolated by genetic selection. two different hybrids were found with the same e. coli segment inserted in opposite orientations. both hybrids produced similar levels of ligase as measured in crude extracts of infected cells. | 1975 | 1103146 |
| characterization of a novel, low-molecular-weight dna-binding protein from escherichia coli. | a low-molecular-weight (7000), heat-stable protein--hu--that stimulates transcription of bacteriophage lambda dna by e. coli rna polymerase was purified from e. coli extracts using affinity chromatography on dna-cellulose. hu binds to native dna, resulting in an apparent thickening of the dna chains as revealed by electron microscopy. contrary to dna unwinding proteins, it causes no destabilization of the double helix. hu differs from previously described transcription factors (h1, d, etc.) and ... | 1975 | 1103148 |
| bacteriophage lambda induction causes increased production of e. coli lysine transfer rna. | 1975 | 1103738 | |
| recovery of phage lambda from ultraviolet damage. | recovery of phage lambda from ultraviolet damage can occur, in the dark, through three types of repair processes as defined by microbiological tests: (1) host-cell reactivation, (2) prophage reactivation, and (3) uv reactivation. this paper reviews the properties of the three repair processes, analyzes their dependence on the functioning of bacterial and phase genes, and discusses their relationship. progress in the understanding of the molecular mechanisms underlying the three repair processes ... | 1975 | 1103822 |
| deoxyribonucleic acid modification by intermediate-type modification mutants of escherichia coli k-12 and b. | the modification of bacteriophages grown on r-m+/- restriction and modification mutants of escherichia coli k-12 or b appears to be related to the number of restriction-specific sites in the viral genome. bacteriophage fd and its mutant u1 fd, which carry two and one b-specific sites, respectively, are not modified in vivo by rb-mb+/- mutant strains. in vitro treatment of fd rf-b+/- deoxyribonucleic acid (dna) or u1 fd rf-b+/- dna by endo r-eco b results in cleavage of the substrate dna. lambda ... | 1975 | 1104586 |
| excision of bacteriophage lambda from a site in the arabinose b gene. | a lambda lysogen with the prophage inserted into the arabinose b gene of escherichia coli strain k-12 has been prepared. induction of the phage from this lysogen yields viable phage at a frequency 4 x 10(-6) that found for induction of lysogens with phage inserted at the normal attachment site. over 30% of the phage particles induced from the insertion in ara are arabinose-transducing phage. the excision end points of 62 independently isolated, nondefective arac-transducing phage containing less ... | 1975 | 1104587 |
| petit lambda, a family of particles from coliphage lambda infected cells. | 1975 | 1104865 | |
| phage lambda receptor chromosomes for dna fragments made with restriction endonuclease iii of haemophilus influenzae and restriction endonuclease i of escherichia coli. | 1975 | 1104875 | |
| the sensitivity of bacteriophage lambda dna to restriction endonuclease rii. | 1975 | 1104876 | |
| induction of error-prone repair as a consequence of dna ligase deficiency in escherichia coli. | dna ligase deficiency is shown to induce generalized mutator activity in e. coli. this mutator activity is unaffected by 3 mug/ml of chloramphenicol but is abolished both in lig-reca double mutants and by incubation with 20 mug/ml of chloramphenicol. dna ligase deficiency is also shown to reactivate ultraviolet light-irradiated phage lambda and t7 and to increase both spontaneous and ultraviolet light-induced mutagenesis in phage lambda, all of which are abolished in lig-reca strains. interactio ... | 1975 | 1105587 |
| an early regulatory gene of salmonella phage p22 analogous to gene n of coliphage lambda. | 1975 | 1105960 | |
| [isolation of a protein factor increasing the infectivity of bacteriophage lambda dna]. | 1975 | 1106973 | |
| letter: the dna synthesis of u.v.-irradiated lambda phage in a u.v.-sensitive host bacterium. | 1975 | 1107241 | |
| reversible interaction between coliphage lambda and its receptor protein. | 1975 | 1107562 | |
| prophage induction and cell division in e. coli. iii. mutations sfia and sfib restore division in tif and lon strains and permit the expression of mutator properties of tif. | in e. coli k12, cell filamentation promoted by tif is enhanced by the lon mutation; in contrast, prophage induction and repair of uv-irradiated phage lambda, also promoted by tif, are not affected by lon. from a tif lon double mutant, "revertants" having recovered the ability to divide at 41 degrees were isolated, among which most (95%) had also lost their lon filamentous phenotype after ultraviolet (uv) irradiation. from these 95% of revertants: (1) 94% are suppressed for the whole tif phenotyp ... | 1975 | 1107802 |
| genetic consequences of transfection with heterduplex bacteriophage lambda dna. | the role of rectification of heteroduplex heterozygotes in the formation of recombinant genotypes involving closely linked markers has been examined. heteroduplex molecules of bacteriophage lambda dna, heterozygous at several alleles, have been constructed and the genetic composition of phage present in infective centers derived by transfection with such molecules has been determined. allele loss and concomitant recombinant formation is frequent, and appears to reflect marker specificity as well ... | 1975 | 1107809 |
| effects of bacteriophage t4-induced modification of escherichia coli rna polymerase on gene expression in vitro. | after t4 bacteriophage infection of e. coli a complex series of events take place in the bacterium, including gross inhibition of host transcription and discrete changes in the classes of the genes of t4 that are transcribed. accompanying these changes in the pattern of transcription one finds t4-induced changes in the rna polymerase (ec 2.7.7.6; nucleosidetriphosphate:rna nucleotidyltransferase). the effects of modified polymerase on transcription can be advantageously analyzed in a dna-directe ... | 1975 | 1108008 |
| inhibtory effect of colicin e2 on transport systems of escherichia coli in the presence of the rex gene of lambda prophage. | purified colicin e(2) was found to cause marked inhibition of the permeation rate of o-nitrophenyl-galactoside (onpg) in several lambda-lysogenic strains of escherichia coli in the presence of chloramphenicol to prevent prophage induction. the inhibitory effect of colicin e(2) on transport systems was analyzed with cells of e. coli cp78(lambda). the dose of colicin e(2) for the half-maximum inhibition of the onpg-permeation rate was about 9 molecules of the colicin per bacterium under the aerobi ... | 1975 | 1108779 |
| preparation and photochemical properties of strand-specific 5-bromouracil-substituted lambda phage. | 1975 | 1110980 | |
| morphogenesis of the tail of bacteriophage lambda. | 1975 | 1111212 | |
| [isolation of a dna fragment containing phage lambda repressor gene]. | 1975 | 1112180 | |
| functional inactivation of bacteriophage lambda morphogenetic gene in rna. | 1975 | 1113861 | |
| positive and negative regulation by the cii and ciii gene products of bacteriophage lambda. | 1975 | 1114699 | |
| amber red- mutants of phage lambda. | 1975 | 1114701 | |
| isolation of nonsense mutants in the morphogenetic region of the bacteriophage lambda chromosome. | 1975 | 1114710 | |
| sequence of the or operator of phage lambda. | a sequence of 79 nucleotides from the lambda or operator is obtained by primed transcription of repressor protected dna fragments. the sequence contains the primary repressor binding site plus partial duplications which can be interpreted as secondary repressor binding sites. | 1975 | 1117995 |
| sequence of the pr promoter of phage lambda. | the rna polymerase binding site from the lambda pr promoter was isolated and sequenced. this dna fragment contains the transcription initiation site and shares 25 nucleotides with or. the sequence preceding the initiation site suggests that the promoter recognition site is not identical with the tight binding and initiation site. | 1975 | 1117996 |
| detection by electron microscopy of photo-induced denaturation in lambda dna. | we have used an electron microscope to study localized denatured regions in ultraviolet-irradiated dna. dna from bacteriophage lambda was uv-irradiated and then prepared for electron microscopy after fixing in buffered (ph 9.5) formaldehyde solutions at 25 degrees c. the denatured regions observed corresponded to those described by inman and schnös (1) who used alkaline denaturation to preferentially destroy thymine-adenine base pairing. in uv-irradiated dna, pairs of neighboring thymine residue ... | 1975 | 1121421 |
| regulation of early gene expression in bacteriophage lambda: effect of tof mutation on strand-specific transcriptions. | 1975 | 1129947 | |
| genetic analysis of the tof gene in the bacteriophage lambda genome. | 1975 | 1129948 | |
| specific hydrolysis of the cohesive ends of bacteriophage lambda dna by three single strand-specific nucleases. | procedures have been worked out for aspergillus nuclease s1 and mung been nuclease to quantitatively cleave off both of the 12-nucleotide long, single-stranded cohesive ends of lambdadna. this cleavage is indicated by the almost complete elimination of the repair incorporation of radioactive nucleotides by dna polymerase into the digested dna. with s1 nuclease, cleavage was complete at 10 degrees as well as at 30 degrees. under the conditions for quantitative cleavage of the single-stranded regi ... | 1975 | 1141222 |
| the synthesis of a dna duplex corresponding to the icosanucleotide sequence at the 5' end of messenger rna from the gene n of bacteriophage lambda. | in connection with work on the nucleotide sequence of the promoter for the gene n of bacteriophage lambda as well as a study of the mechanism of transcription, a 20-unit long dna duplex corresponding to the known sequence at the 5' end of the above gene transcript has been synthesized. for synthesis, the required duplex was divided into the following deoxyribooligonucleotides: a) the dodecanucleotide, d-a-t-c-a-g-c-a-g-g-a-c-g (ii); b) the octanucleotide, d-c-a-c-t-g-a-c-c- (iv); c) the hexanucl ... | 1975 | 1141242 |
| rec-mediated recombinational hot spot activity in bacteriophage lambda. iii. chi mutations are site-mutations stimulating rec-mediated recombination. | 1975 | 1142440 | |
| fine structures in denaturation curves of bacteriophage lambda dna. their relation to the intramolecular heterogeneity in base compositon. | precise recording of polyphasic optical melting curves was carried out for three kinds of bacteriophage lambda dna differing in length (lambdac1857s7, lambdacib2 and lambdacib2b5). each of denaturation steps in melting profiles was characterized by two parameters, the melting temperature and the relative size. any difference in fine structures in melting profiles was not recognized between the intact lambdaci857s7dna and the dna fragmented into halves. the change in fine structures in melting pr ... | 1975 | 1148236 |
| integrative recombination in bacteriophage lambda: analysis of recombinant dna. | 1975 | 1152037 | |
| control of bacteriophage lambda repressor synthesis after phage infection: the role of the n, cii, ciii and cro products. | 1975 | 1152053 | |
| control of bacteriophage lambda repressor synthesis: regulation of the maintenance pathway of the cro and ci products. | 1975 | 1152054 | |
| the isolation and characterization of plaque-forming arabinose transducing bacteriophage lambda. | 1975 | 1152060 | |
| defective bacteriophage lambda chromosome, potential vector for dna fragments obtained after cleavage by bacillus amyloliquefaciens endonuclease (bami). | 1975 | 1157934 | |
| [inactivating effect of o-methylhydroxylamine on phage lambda and its mutants]. | the kinetics of inactivation of lambda+, lambda c160, lambda nsus7, lambda gsus9, lambda tsus6 phages under the effect of o-methylhydroxylamine was studied. inactivation curves of all the phages under study were found to be of a complex character and early in the reaction (up to 4 hours) to deviate from exponential dependence of the inactivation rate upon the time of incubation with the mutagen. all the phages under study showed differences in the inactivation rates early in the reaction. consta ... | 1975 | 1162960 |
| role of genes o and p in the replication of bacteriophage lambda dna. | 1975 | 1177302 | |
| evidence for a dual control of the initiation of host-cell lysis caused by phage lambda. | the timing of host-cell lysis by coliphage lambda is controlled by two separable systems. the lambdas gene product acts as a positive effector of lysis while another protein, the lysis regulator, is an inhibitor of lysis. if the continuous function of the lysis regulator is interrupted in phage infected cells immediate lysis ensues. this lysis requires metabolic energy but not s gene activity. in contrast, s protein activity is stimulated by agents which uncouple and which block oxidative phosph ... | 1975 | 1177863 |
| sequence of the promoter-operator proximal region of the major leftward rna of bacteriophage lambda. | the sequence of the first 149 nucleotides of the major leftward rna of bacteriophage lambda has been determined. preliminary sequence information was also obtained for a portion of the untranscribed area immediately upstream of the point on the template when rna synthesis normally starts. several restriction endonuclease sites, deletion endpoints, and single base changes have been localized within the sequence. the first potential translation initiation codon which is not followed by an in-phase ... | 1975 | 1178525 |
| the structure of tubular head forms of bacteriophage lambda; relation to the capsid structure of petit lambda and normal lambda heads. | 1975 | 1179647 | |
| effect of chloramphenicol on early mrna synthesis in bacteriophage lambda. | the n gene product induces lambda-delayed early mrna synthesis. this transcription was sensitive to chloramphenicol at the very early stage of phage development, but became resistant within 2-4 min after infection. however, the same transcription was sensitive to the antibiotic throughout phage development if lambda tof- mutant was used as the infecting phage. the results suggest involvement of the tof gene in lambda early transcription; the tof product may act as a stabilizer of the n gene func ... | 1975 | 1180971 |
| tandem genetic duplications in phage lambda. iv. the locations of spontaneously arising tandem duplications. | 1975 | 1185775 | |
| polarized packaging of bacteriophage lambda chromosomes. | 1975 | 1185777 | |
| a simple method for making new transducing lines of coliphage lambda. | a variety of novel transducing lines of phage lambda can be obtained by induction of a mixed culture of abnormal lysogens. such a culture is simply made by mass lysogenization of a host lacking the normal prophage attachment site. | 1975 | 1186657 |
| rec-mediated recombinational hot spot activity in bacteriophage lambda. iv. effect of heterology on chi-stimulated crossing over. | a chi mutation in phage lambda stimulates rec-mediated crossing over more to one side of itself than to the other; stimulation, which is maximal near chi, can occur at some distance from the chi site as well. a gross heterology differentiating the two recombining parents does not interfere with the distant chi-stimulated crossover whether the heterology is at the chi site or between the chi site and the distant interval in which recombination is monitored. these conclusions hold whether recombin ... | 1975 | 1186661 |
| model for arrangement of minor structural proteins in head of bacteriophage lambda. | 1975 | 1186870 | |
| dna as substrate for packaging into bacteriophage lambda, in vitro. | 1975 | 1195386 | |
| studies on the late replication of phage lambda: rolling-circle replication of the wild type and a partially suppressed strain, oam29 pam80. | 1975 | 1195390 | |
| [hybrid molecules of phage lambda dna and co1 e1 plasmid]. | 1975 | 1204431 | |
| [mechanism of packing dna into the head of bacteriophage lambda]. | 1975 | 1204455 | |
| [relation of the biological activity of bacteriophage lambda dna to the structure of the "cohesive" ends]. | 1975 | 1204464 | |
| proceedings: the detection of activated carcinogens with bacteriophage lambda. | 1975 | 1212389 | |
| [biological activity of different forms of bacteriophage lambda dna]. | hershey circles and linear tandem aggregated forms of dna have been obtained in vitro and treated with polynucleotide ligase to form phosphodiester bond. using zone centrifugation in glycerol gradient covalently closed circles and linear dimers have been purified and their biological activity investigated. it was found that closed circular molecules lost most, if not all, of their activity in cacl2-dependent system. in order to investigate the biological activity of tandem dimer molecules, hybri ... | 1975 | 1219377 |
| [influence of the reca- mutation on spontaneous filamentation and the titer of the lambda phage in ylonb- mutants of e. coli k12 (lambda)]. | a study was made of the effect of reca- mutation on the spontaneous filament formation and the spontaneous induction of the lambda prophage in the e. coli k12 strain bearing lonb- mutation. it was revealed that in the absence of a functionally-active product of the reca- gene the lonb- strain of e. coli k12 displayed but a partial depression of spontaneous formation of filamentous forms and of spontaneous induction of the lambda prophage. | 1975 | 1221730 |
| [dissociation of lambda phage from the host chromosome]. | 1975 | 1240271 | |
| 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 |
| [competence in escherichia coli cells. iii. formation of competent states in escherichia coli x7026 and escherichia coli hfr h cells during storage in different conditions]. | the competence formation in 2 strains of escherichia coli x7026 and hfr h to isolated phage gamma dna after the prolonged treatment of cells with ca++ ions at low temperatures was investigated. in both strains studied the sensitivity of cells to phage lambda dna increased during several days of maintenance at 4 degrees c in 0.2 m cacl2, and reached the maximal value in 24-48 hours for e. coli hfr h cells, and in 72-96 hours for e. coli x7026 cells. cells maintained in cacl2 for 24 hours and more ... | 1975 | 767199 |
| inhibitory effect of u.v. -irradiation on the formation of twisted circular lambda dna. | ultra-violet irradiation of lambda phage results in an inhibition of conversion of lambda dna in host cells from the initial linear form to twisted circular form. the formation of open circular lambda dna in vitro (formation of hershey's circle) was quite resistant to the irradiation. the occurrence of denaturation of ultraviolet irradiation was detected in lambda dna. | 1975 | 1079515 |
| mechanisms of protection of gamma-irradiated bacteriophage lambda by proflavine. | the protective effect of proflavine on gamma-irradiated bacteriophage lambda and its isolated dna was investigated under conditions of predominantly indirect or direct effects. in both conditions addition of small amounts of the dye during irradiation of phage or dna was shown to enhance their biological activity. protection against indirect effects results probably from extensive scavenging of radioinduced water radicals within the medium. on the other hand the results obtained at minus 196 deg ... | 1975 | 1080138 |
| different types of thermoconditional clear plaque-mutants and prophage induction by heat or cold of serratia phage kappa. | phage kappa of seratia marcescens was treated with different mutagens to induce thermoconditional clear plaque-mutants. 176 mutants obtained were analysed by crosses and found to be located in clear plaque-region iii. two types resembling the mutants t2 and t1 of phage lambda were identified. lysogens for the mutant 126 can be induced by heat and even by cold whereas they are scarcely inducible by uv. nevertheless, a 126 prophage like a uv inducible ct 163 prophage can be sensitized to thermoind ... | 1975 | 1179753 |
| morphogenesis of the tail of bacteriophage lambda. iii. morphogenetic pathway. | 1975 | 1237629 | |
| the starting point and direction of rolling-circle replicative intermediates of coliphage lambda dna. | intermediates of lambda dna replication in the second half of the latent period after phage lambda infection were isolated and investigated in the electron microscope by denaturation mapping. the isolated replicative forms (rf) are predominantly single branched circular dna. the starting points of replication in these lariat molecules located at the same region as the first round lambda dna replication. about 60% of the rf replicate from left to right and the other 40% replicate in the reverse d ... | 1975 | 1214777 |
| genetic heterozygosity in unreplicated bacteriophage lambda recombinants. | bacteriophage crosses using density-labeled parents have been carried out under conditions restricting dna synthesis. the parental material and genetic contributions to progeny manifesting recombination within a genetic interval sufficiently short to exhibit high negative interference have been examined. the unreplicated products of recombination isolated as phage particles appear to contain long continuous heteroduplex regions which are heterozygous for the closely linked markers. recombination ... | 1975 | 1205127 |
| genetic exchanges induced by structural damage in nonreplicating phage lambda dna. | genetic recombination between irradiated lambda phage and the unirradiated lambda prophage in homoimmune lysogens has been studied under conditions in which phage dna replication and repair were controlled. the lambda phage were exposed to one of three treatments before infecting the lysogens: (a) 254-nm light, which produces pyrimidine dimers and other photoproducts; (b) 313-nm light with acetopheneone d, which produces thymine dimers and a different spectrum of other photoproducts; (c) 360-nm ... | 1975 | 1191175 |
| 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 |
| 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 |
| 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 |
| hyperfine structure in melting profile of bacteriophage lambda dna. | 1976 | 1252601 |