| protection and host cell repair of irradiated lambda phage. i. irradiation of normal phage with ultraviolet light. | | 1969 | 4897977 |
| recombination in bacteriophage lambda. 3. studies on the nature of the prophage attachment region. | | 1969 | 4904107 |
| two stages in the replication of bacteriophage lambda dna. | | 1969 | 4904393 |
| regulation of bacteriophage lambda development by gene n: properties of a mutation that bypasses n control of late protein synthesis. | | 1970 | 4909409 |
| unbiased synthesis of pulse-labeled dna framents of bacteriophage lambda and t4. | | 1970 | 4922215 |
| control of late messenger rna synthesis during lambda phage development. | | 1971 | 4926028 |
| properties of phage lambda dna-rna polymerase complexes isolated from escherichia coli (lambda). | | 1970 | 4912207 |
| crypticogenicity of bacteriophage lambda. | | 1970 | 4920426 |
| effect of carbohydrates on induction of bacteriophage lambda. | | 1970 | 4920472 |
| role of exonuclease and beta protein of phage lambda in genetic recombination. v. recombination of lambda dna in vitro. | the sequential action of lambda exonuclease and polynucleotide ligase upon redundant joint molecules is sufficient to produce intact polynucleotide chains and heat-stable, biologically active molecules of lambda dna, whereas the action of ligase alone is insufficient. these results (a) confirm the previously described mechanism of single-strand assimilation, including a subsidiary mechanism by which the further action of lambda exonuclease is arrested when a redundant strand is completely assimi ... | 1971 | 4934524 |
| light-induced cross-linking of dna in the presence of a furocoumarin (psoralen). studies with phage lambda, escherichia coli, and mouse leukemia cells. | | 1970 | 4927248 |
| polar mutations in the left arm of bacteriophage lambda i434. | by studying complementation between frameshift and nonsense mutants located in the structural genes for the head of bacteriophage lambdai434, we found mutations in gene b which are polar on genes c and d and one mutation in gene e which is polar on gene f. | 1971 | 4927522 |
| [the irreparability of damage caused by 1m hydroxylamine in lambda phage when submitted to passage in e. coli hcr+ and hcr- cells]. | | 1970 | 4932341 |
| mutants of bacteriophage lambda defective in vegetative genetic recombination. | | 1968 | 4938547 |
| [induction of lambda phage and transduction in bacterial forms with changed synthesis of the cell wall]. | | 1971 | 4938667 |
| bacteriophage p2: interaction with phage lambda and with recombination-deficient bacteria. | | 1971 | 4943192 |
| bacterial mutants in which the gene n function of bacteriophage lambda is blocked have an altered rna polymerase. | bacterial mutants have been isolated, called gron, that block phage development by interference with the action of the product of the phage n gene. lambdatrp phages, which depend on the n product for the synthesis of tryptophan enzymes, do not make these enzymes in gron bacteria. two type of phage mutants have been isolated that can overcome the gron block. one type makes an altered n product, the other contains an n-bypass mutation. the gron mutation is closely linked to the rifamycin-resistanc ... | 1971 | 4943550 |
| establishment and maintenance of repression by bacteriophage lambda: the role of the ci, cii, and c3 proteins. | to define the events necessary for the establishment and maintenance of repression in a lambda-infected cell, we have studied the requirements for efficient synthesis of the ci protein ("lambda-repressor"). three classes of lambda mutants defective in the establishment of repression are also defective in the appearance of ci protein activity at the normal time. two of these mutational classes (cii(-) and ciii(-)) probably result from inactivation of lambda-specified proteins, but the third class ... | 1971 | 4943791 |
| purification and properties of 3-deoxy-d-arabinoheptulosonic acid-7-phosphate synthetase (phe) from a lambda arog+ transductant of escherichia coli. | by incorporating arog, the structural gene for 3-deoxy-d-arabinoheptulosonic acid-7-phosphate (dahp) synthetase (phe), into the genome of a heat-inducible susr60 mutant of phage lambda, it has been possible to increase the intracellular levels of dahp synthetase (phe) in a lysogenized strain of escherichia coli some 15-fold over levels found in the wild-type strain. by using this strain, the enzyme has been purified approximately 2,000-fold compared with wild type, and various kinetic parameters ... | 1971 | 4937786 |
| ultraviolet- and x-ray-induced responses of a deoxyribonucleic acid polymerase-deficient mutant of escherichia coli. | escherichia coli k-12, polal(-) is a mutant strain whose extracts are deficient in kornberg deoxyribonucleic acid (dna) polymerase activity. we have compared the mutant and parental strains on the basis of a number of responses to ultraviolet (uv) and x-irradiation. for both types of radiation, the mutant is more sensitive by approximately the same factor as measured by reduction in colony formation, depression of dna synthesis, and enhancement of dna degradation. the rate of repair of x-ray-ind ... | 1971 | 4935330 |
| immunolabelling of bacteriophage lambda receptor protein (lamb) on thin sections of e. coli embedded in lowicryl. | lamb is one of the major cellular proteins when e. coli is grown in the presence of maltose and is localized in the outer membrane. previous immunolabellings obtained with monoclonal antibodies showed that this protein is a transmembrane protein and led to the detection of 4 epitopes exposed on the cell surface and 2 located on the inner surface of the outer membrane (scheckman et al., 1983). in the present study, we have used this biological model in order to see whether these two classes of ep ... | 1984 | 6084531 |
| a v-sis oncogene protein produced in bacteria competes for platelet-derived growth factor binding to its receptor. | the oncogene of simian sarcoma virus, v-sis, encodes a protein which is homologous to human platelet-derived growth factor (pdgf). this v-sis-encoded protein was expressed in bacteria using an inducible promotor of lambda phage. soluble extracts from these bacteria contained a substance which competed with 125i-pdgf for pdgf receptor sites in fibroblast membranes. the receptor competition activity was correlated with the presence of the v-sis-encoded protein as assessed by genetic and immunochem ... | 1984 | 6088510 |
| analysis of the escherichia coli proba locus by dna and protein sequencing. | a 2.9 kb dna fragment carrying the escherichia coli proba region, which encodes the first two enzymes of the proline biosynthetic pathway, was subcloned onto an expression plasmid carrying both the bacteriophage lambda pl promoter (lambda pl) and the lambda gene encoding a thermolabile ci repressor protein (ci857). derepression of the lambda pl promoter by thermal inactivation of the ci857 repressor protein resulted in the simultaneous overproduction of the prob (gamma-glutamyl kinase) and proa ... | 1984 | 6089111 |
| expression of normal and transforming h-ras genes in escherichia coli and purification of their encoded p21 proteins. | the h-ras gene of the balb murine sarcoma virus (balb-msv) was placed under the transcriptional control of the tightly regulated pl promoter of bacteriophage lambda in the expression vectors pev-vrf-1 and prc23. upon derepression of the pl promoter, large amounts (10-20% of total cellular protein) of the h-ras gene product p21 are synthesized in escherichia coli. we constructed three h-ras gene expression vectors, designated pjcl-h5, pjcl-e30, and pjcl-33. pjcl-h5 directs the synthesis of p21, a ... | 1984 | 6089191 |
| analysis of two potential shuttle vectors containing herpes simplex virus defective dna. | two potential shuttle vectors which contained the identical herpes simplex virus type 1 (hsv-1) defective particle dna (ddna), but prokaryotic dna of different origins, were examined for their stability when propagated in eukaryotic cells, and for their efficiency as shuttle vectors. each chimeric molecule contained a 9.5 kilobase-pair (kb) ecori fragment (hsv12-7) representing a single unit of a class i hsv-1 ddna. this ddna was cloned into the bacteriophage lambda (lambda) vector lambda gtwes ... | 1984 | 6090565 |
| a phage lambda endonuclease controlled by genes o and p. | | 1971 | 4937245 |
| extension of bacteriophage lambda host range: selection, cloning, and characterization of a constitutive lambda receptor gene. | a set of plasmids has been constructed that carry a constitutive lamb gene (lambc phenotype) from escherichia coli and that confer functional phage lambda receptors to bacteria other than e. coli. this e. coli lambc strain has been selected to escape both maltose-inducible and glucose-repressible control. constitutivity results from an is-3 insertion, carrying a mobile promoter, proximal to lamb. the lambc dna has been cloned into both broad and narrow host-range plasmids, and the resulting ptro ... | 1984 | 6091132 |
| antitermination of e. coli rrna transcription is caused by a control region segment containing lambda nut-like sequences. | we have localized the antitermination system involved in e. coli ribosomal rna transcription and compared it with antitermination in the lamboid bacteriophages. in vivo experiments with gene-fusion plasmids were used to examine the ability of specific areas of the rrng control region to convert an ordinary transcription complex into antitermination transcription complex. a 67 bp restriction fragment immediately following the rrng p2 promoter decreased transcription termination about 50%. this fr ... | 1984 | 6091902 |
| resolution of synthetic att-site holliday structures by the integrase protein of bacteriophage lambda. | site-specific recombination of the bacteriophage lambda genome into and out of the host bacterial genome is postulated to involve the formation of holliday structure intermediates by reciprocal single-strand exchanges. synthetic analogues of the predicted recombination intermediates are resolved in vitro by the protein product of the lambda int gene. some of the structural features and reaction conditions for this genetic recombination can now be defined. | 1984 | 6092961 |
| plasmid vectors for the rapid isolation and transcriptional analysis of human beta-globin gene alleles. | we describe the construction and characterization of miniplasmid vectors that can be used to isolate and express normal and mutant alleles of the human beta-globin gene. these vectors, designated pi sv beta plasmids, contain a bacterial origin of replication and selectable marker, a 5'-flanking beta-globin dna fragment that can be used for recombination screening (seed, 1983), and simian virus 40 (sv40) sequences that allow accurate and efficient expression of the beta-globin gene transfected in ... | 1983 | 6094959 |
| cloning, nucleotide sequence and high level expression of the gene coding for the connector protein of bacillus subtilis phage phi 29. | the phi 29 dna restriction fragment hindiii-d, shown to contain gene 10 coding for the connector protein, has been cloned in plasmid pplc28 under the control of the pl promoter of phage lambda. after heat induction to inactivate the lambda repressor, a protein with the electrophoretic mobility of the connector protein p10 was synthesized, accounting for about 30% of the total escherichia coli protein after 3 h of induction. the 2205 nucleotide-long sequence of the cloned hindiii-d fragment has b ... | 1984 | 6096227 |
| l factor that is required for beta-galactosidase synthesis is the nusa gene product involved in transcription termination. | the dna-dependent in vitro synthesis of escherichia coli beta-galactosidase requires the presence of a soluble protein referred to as l factor [kung, h., spears, c. & weissbach, h. (1975) j. biol. chem. 250, 1556-1562]. in the present study, comparison of physical, immunological, and biological properties shows that l factor is the product of the e. coli nusa gene. the nusa gene product is known to interact with bacteriophage lambda n gene protein and to prevent premature termination of transcr ... | 1980 | 6154941 |
| studies on the e. coli gronb (nusb) gene which affects bacteriophage lambda n gene function. | escherichia coli mutants, called gronb, which block the growth of bacteriophage lambda at the level of action of the gene n product, have been isolated as survivors at 42 degrees c of bacteria carrying a) the defective prophage lambda bio11 i lambda ci857 delta h1 or b) the pcr1 plasmid containing the ecori immunity fragment of phage lambda ci857. in addition, gronb bacterial mutants have been isolated at 37 degrees c, as large colony formers in the presence of lambda i lambda ci h434, lambda i ... | 1980 | 6161293 |
| absortive lysogenization of bacteriophage lambda b2 and residual immunity of non-lysogenic segregants. | | 1967 | 5340186 |
| assembly pathway of newly synthesized lamb protein an outer membrane protein of escherichia coli k-12. | the assembly of newly induced lamb protein (phage lambda receptor) was investigated in an operon fusion strain of escherichia coli, in which the lamb gene is expressed under lac promoter control. the induction kinetics both for total cellular and for cell surface-exposed lamb protein were studied by immunochemical detection methods, using two distinct antisera directed against detergent-solubilized lamb trimers and completely denatured lamb monomers, respectively. anti-trimer antibodies recogniz ... | 1984 | 6204059 |
| identification of transfer rna suppressors in escherichia coli. iv. amber suppressor su+6 a double mutant of a new species of leucine trna. | an escherichia coli dna fragment containing an su+6 amber suppressor gene (supp) was cloned into a lambda gt lambda ch vector by the shotgun method, selecting a su+6 transducing phage lambda psu+6. through prophage integration followed by induction occurring at the transducing region of the lambda psu+6 in su- e. coli, a counterpart transducing phage carrying the wild-type allele (su degrees 6) was isolated (lambda psu degrees 6). the fingerprint of a trna encoded by lambda psu degrees 6 was ide ... | 1984 | 6207302 |
| solid-phase sequence analysis of polypeptides eluted from polyacrylamide gels. an aid to interpretation of dna sequences exemplified by the escherichia coli unc operon and bacteriophage lambda. | an approach to sequencing proteins by the solid-phase method combined with isolation of proteins and polypeptides by gel electrophoresis is described. mixtures of proteins or polypeptides resulting from digests are fractionated in the presence of dodecylsulphate in polyacrylamide gels. they are detected with coomassie blue, eluted, selectively reacted with porous glass derivatives and sequenced in their amino-terminal regions with the aid of a new microsequencer. alternatively they can be analys ... | 1982 | 6210528 |
| the formation of superinfection-double lysogens of phage lambda in escherichia coli k-12. | | 1965 | 5318339 |
| site-specificity of abnormal excision: the mechanism of formation of a specialized transducing bacteriophage lambda plac5. | molecular mechanism of the specialized transducing bacteriophage lambda plac5 formation has been studied. phage-bacterial dna junctions in lambda plac5 dna are localized and primary structure of regions of the abnormal excisional recombination leading to the phage formation is elucidated; the crossover region proved to be comparable with the central part of attp and attb sites (the core and the adjacent tetranucleotide) in length and degree of homology. bacterial insert in lambda plac5 dna is sh ... | 1984 | 6091038 |
| identity of a chi site of escherichia coli and chi recombinational hotspots of bacteriophage lambda. | | 1982 | 6210783 |
| rna splicing mutation in an aberrantly rearranged immunoglobulin lambda i gene. | the mouse cell line mopc 315 is an iga (lambda ii)-producing myeloma. we have studied a derivative of mopc 315 that secretes normal lambda ii chains but no heavy chain. this derivative, mopc 315-26, was found to contain a rearranged lambda i gene in addition to a rearranged lambda ii gene. the rearranged lambda i gene was cloned into bacteriophage lambda dna and its structure was studied. the lambda i gene was found to have arisen by an aberrant recombination event that resulted in a single base ... | 1981 | 6171827 |
| purification of the bacteriophage lambda xis gene product required for lambda excisive recombination. | excision of the lambda prophage from the chromosome of its escherichia coli host requires the products of the two viral genes int and xis. this paper reports a purification of the lambda xis gene product using a complementation assay in which functional xis must be added to purified int and an e. coli-derived host factor extract. excisive recombination between a left (attl) and right (attr) prophage attachment site cloned on the same plasmid dna substrate occurred efficiently under these conditi ... | 1982 | 6213611 |
| analysis of lambda insertions in the fucose utilization region of escherichia coli k-12: use of lambda fuc and lambda arga transducing bacteriophages to partially order the fucose utilization genes. | escherichia coli k-12 strains have deletions for the normal lambda integration site were lysogenized with bacteriophage lambda at a site within the l-fucose utilization system (fuc). the frequency of lambda integration at this site is approximately 2 x 10(-8) to 5 x 10(-7). studies of the lytic properties of these strains indicated very infrequent cell lysis with a relatively low phage burst size. transductional ability of the phage lysates was found to be normal, comparable to that found in con ... | 1982 | 6214544 |
| construction of recombinant lambda phages that carry the e. coli recb and recc genes. | a fragment of the e. coli chromosome including the recc gene has been cloned by in vitro recombinant dna techniques into a phage lambda vector to give the recombinant phage lambda drecc. this was used to derive the phage lambda drecbc by in vivo recombination. on lysogenisation of recb and recc mutants with lambda drecbc wild levels of uv-resistance and recbc dnase activity were restored. infection of e coli with lambda drecbc led to the synthesis of phage-coded proteins of 125 kilodaltons (kd) ... | 1982 | 6211590 |
| formation of oligomeric structures from plasmid dna carrying cos lambda that is packaged into bacteriophage lambda heads. | plasmids that carry cos lambda, the region necessary for lambda phage packaging and that are as small as four kilobases in size can be packaged into lambda phage heads in head-to-tail tandem oligomeric structures. multimeric oligomers as large as undecamers have been detected. oligomer formation depends upon the products of red and gam of lambda, and the general recombination occurs between different plasmids that share homologous dna regions. the packaging efficiency of plasmids depends on its ... | 1983 | 6217189 |
| a comparison of the requirements for antitumour activity and antibacteriophage lambda activity for a series of non-intercalative dna-binding agents. | a series of non-intercalative dna-binding agents, comprising mainly bisquaternary ammonium heterocyclic compounds, has been found to inhibit strongly the production of bacteriophage lambda following its induction in escherichia coli. the inhibition is much greater than that found with a number of dna intercalating agents, including 9-aminoacridine, ethidium and daunorubicin. the inhibition correlated significantly with antitumour effect, as measured in a life extension assay with l1210 leukaemia ... | 1982 | 6212240 |
| purification and characterization of reca protein from salmonella typhimurium. | reca protein was purified to homogeneity from salmonella typhimurium ta98 strain after induction of the cells by nalidixic acid. the purification was monitored with a radioimmune assay and involved a specific elution of the protein by atp from a single-stranded dna-cellulose column. from 240 liters of cell culture we obtained 40 mg of reca protein which was more than 98% pure. this protein exhibited the same molecular weight as measured on sodium dodecyl sulfate-polyacrylamide gel and the same i ... | 1983 | 6219107 |
| cloning of colicin e1 tolerant tolc (mtcb) gene of escherichia coli k12 and identification of its gene product. | a mutation in the tolc(mtcb) gene of escherichia coli k12 results in increased sensitivity to sodium dodecylsulfate (sds), sodium deoxycholate, basic dyes, mitomycin c, and bleomycin, and makes the cell tolerant to the killing action of colicin e1. from lysogens with lambda ci857s7 integrated at a secondary attachment site, a transducing phage (lambda dtolc+) that transduces a tolc recipient to sds resistance was isolated. a recombinant dna molecule was constructed in vitro from plasmid pbr322 a ... | 1982 | 6219270 |
| cleavage of lambda repressor and synthesis of reca protein induced by transferred uv-damaged f sex factor. | transfer of a uv-damaged f sex factor to a recipient lambda lysogen induces prophage lambda development. under these conditions reca protein synthesis was induced and lambda repressor cleaved, as observed upon direct induction, that is, when the recipient lambda lysogen was directly exposed to uv-light. the efficiency of induction of reca protein synthesis in recipient bacteria which had received an irradiated f-lac factor was about 80% of that measured upon direct induction. we observed the sim ... | 1982 | 6213837 |
| features of bacteriophage lambda: analysis of the complete nucleotide sequence. | | 1983 | 6222866 |
| mutation and w-reactivation of lambda phage by mitomycin c in the excision-defective escherichia coli. | | 1982 | 6216402 |
| gene transfer into animal cells after fusion with bacteriophage lambda-infected e coli protoplasts. | | 1983 | 6227013 |
| expression of the replication region of phage lambda dna cloned into pbr322 in e. coli minicells. | replication region of bacteriophage lambda dna was cloned into pbr322 plasmid by the use of two restriction enzymes--psti and hindiii. the restriction analysis of four obtained plasmids revealed that lambda dna was cloned in both orientations. recombinant plasmids were transferred to the minicell-producing strain of e. coli and synthesis of the plasmid-mediated proteins was analysed by polyacrylamide-gel electrophoresis. all four recombinant plasmids produced lambda dna replication proteins po a ... | 1982 | 6218724 |
| proteolytic processing of phage lambda tail protein gph: timing of the cleavage. | we describe a method for the rapid partial purification of intermediate structures of phage lambda tail assembly, using formaldehyde-fixed escherichia coli cells to precipitate tail-related structures. the purification depends on the specific interaction between the e. coli lambda receptor protein and lambda tail protein gpj. protein compositions of tail assembly intermediates were analyzed to determine when in the assembly sequence the minor tail protein gph is cleaved. gph joins the tail precu ... | 1983 | 6220513 |
| lambda mutation in the escherichia coli rho gene that inhibits the n protein activity of phage lambda. | certain escherichia coli rho mutations, exemplified by rho026, block the growth of phage lambda by interfering with phage gene expression. the phage gene n, whose product suppresses transcription termination, appears to be expressed normally in the mutants, and the functional stability of the n protein is not affected. our data suggest that these rho mutations allow transcription to terminate despite the presence of n. other e. coli mutants displaying a similar phenotype (nus(-)) fail to propaga ... | 1983 | 6225121 |
| facile and gentle method for quantitative lysis of escherichia coli and salmonella typhimurium. | garrett et al. (mol. gen. genet. 182:326-331, 1981) constructed strains of escherichia coli harboring derivatives of plasmid pbr322 that carry the lysis genes (s, r, and rz) of phage lambda. the plasmid construction placed the genes under control of the lactose operon operator-promotor (and thus of lac repressor). induction of e. coli strains carrying these plasmids resulted in rapid lysis of the culture unless the s gene was defective, in which case the cells grew normally. a freeze-thaw treatm ... | 1984 | 6232260 |
| an integration-proficient int mutant of bacteriophage lambda. | we have isolated and characterized a novel int mutant of phage lambda. this mutant promotes efficient recombination between the phage and bacterial attachment sites, but, unlike wild type, does not promote efficient recombination of any other pair of attachment sites tested in most conditions. in particular, recombination between two phage or two prophage attachment sites is poor relative to the wild type frequency. we attribute this unusual phenotype to differences in the distribution of int pr ... | 1984 | 6238223 |
| escherichia coli plasmid vectors for high-level regulated expression of the bacteriophage lambda xis gene product. | the bacteriophage lambda xis protein is one of the proteins required for site-specific excisive recombination by which the lambda prophage is excised from the escherichia coli bacterial chromosome. we cloned the lambda xis gene under the control of several prokaryotic promoters to obtain a sufficient source of the protein for biochemical studies. our results demonstrate that e. coli lac promoter and lambda pl promoter fusions to the xis gene produce high levels of xis protein. induction of the e ... | 1983 | 6229452 |
| [bacteriophage lambda integration into host chromosome (biochemistry of int protein and pleiotropic effects of host factors) (author's transl)]. | | 1980 | 6243784 |
| construction and properties of a cole1::tn3-cos lambda plasmid for determining rna polymerase binding sites on cole1 and tn3. | to determine the location of the rna polymerase binding sites on the cole1 plasmid and tn3 transposon, a special hybrid cole1::tn3-cos lambda molecule was constructed which contains the left arm of phage lambda dna and the right lambda terminal fragment. this permits orienting cole1 molecules, since the rna polymerase binding pattern of these two lambda fragments are known to be distinct. cole1 dna contains seven binding sites and tn3 binds three rna polymerases, with some of the latter probably ... | 1980 | 6247244 |
| cloning of the replication gene o of e. coli bacteriophage lambda and its expression under the control of the lac promoter. | the expression of the replication gene o of bacteriophage lambda was put under the control of the lac promoter-operator region integrated into the pbr322 cloning vehicle. the new plasmid pkk104 was introduced into minicells and the o gene induced by isopropyl-beta-thiogalactoside (iptg). the o protein could be identified as a major component in extracts from these cells, in association with the cell membrane fractions. the molecular weight of the o protein in sds gels is about 33 000, and it is ... | 1980 | 6254838 |
| bacteriophage lambda cloning vehicles for studies of genetic recombination. | a pair of bacteriophage lambda cloning vehicles has been constructed for use in studies of genetic recombination. these phages, lambda rva and lambda rvb, have the following properties: (1) each vector has a single hindiii site in the immunity region, at which segments of dna can be inserted. (2) these hindiii sites are flanked by selectable markers with the following phenotypes: spi+/- (fec+/-) to the left, and imm lambda or imm434 to the right. (3) there is essentially no sequence homology bet ... | 1980 | 6254844 |
| lack of induction of non-targeted mutations in intact bacteriophage by uvb (313 nm), uva (334 nm, 365 nm) and visible (405 nm) irradiation of host cells. | mutation to virulence has been measured in intact bacteriophage lambda 15 infected into host cells pre-treated with uvc (254 nm), uvb (313 nm), uva (334 nm, 365 nm) or visible (405 nm) radiations. we have confirmed that uvc radiation leads to a large enhancement (maximum enhancement factor of 140 in wild-type) of the background spontaneous mutation frequency (non-targeted mutagenesis) and have further shown that this is at least partially dependent on excision repair (maximum enhancement factor ... | 1984 | 6229698 |
| cloning of the exonuclease iii gene of escherichia coli. | overproducers of exonuclease iii (exo iii) were found within a colony bank containing cole1-escherichia coli hybrid plasmids. through the enzymatic ligation of restriction enzyme fragments, the exo iii gene, xth, was transferred to a thermoinducible, integration-proficient lambda phage and to a chimeric cole1-lambda plasmid that was thermoinducible for lambda-directed dna replication. transfer of the xth gene was facilitated by a technique involving prior selection for tn5 insertions into plasmi ... | 1980 | 6260569 |
| the nus mutations affect transcription termination in escherichia coli. | the nusa1 and nusb5 mutations in a partial suppression of polarity and thus transcription termination in escherichia coli. as these mutations block the transcription antitermination activity of bacteriophage lambda n gene product, they paradoxically seem to enhance transcription termination at phage termination sites. the rho mutation hdf026 displays almost identical properties. the observations suggest that the nusa and nusb gene products may act as termination factors analogous to rho protein. | 1981 | 6265784 |
| replication defective rp4 plasmids recovered after chromosomal integration. | phh6000 is a composite replicon made by the in vitro ligation of the incp plasmid rp4 to a fragment of bacteriophage lambda capable of autonomous replication. derivatives were selected in which it had integrated into the escherichia coli chromosome by homologous recombination with the resident lambda prophage, and plasmids were subsequently regenerated from the integrated molecules. although of the same molecular size as phh6000, all had altered properties: those recovered from the chromosome of ... | 1984 | 6231650 |
| isolation of beta-globin-related genes from a human cosmid library. | a human gene library was constructed using an improved cloning technique for cosmid vectors. human placental dna was partially digested with restriction endonuclease mboi; size-fractionated and ligated to bamhi-cut and phosphatase-treated cosmid vector pjb8. after packaging in lambda phage particles, the recombinant dna was transduced into escherichia coli 1400 or hb101 followed by selection on ampicillin for recombinant e. coli. 150 000 recombinant-dna-containing colonies were screened for the ... | 1981 | 6266915 |
| cosmid cloning and transposon mutagenesis in salmonella typhimurium using phage lambda vehicles. | we have constructed a strain of salmonella typhimurium which contains the malb region from escherichia coli and carries the bacteriophage lambda receptor protein in its outer membrane. phage lambda adsorbs to this strain but cannot grow, thus providing a very useful system for transposon mutagenesis of s. typhimurium using lambda vehicles carrying transposons. this system can also be used for cosmid cloning. | 1981 | 6268936 |
| [artificial tn2551 transposon with replicative properties]. | a hybrid plasmid, pbe10 was constructed. it consists of dnas of rsf2124 (cole1 :: tn3) plasmid and pub110 plasmid of staphylococcus aureus. the latter can be stably maintained in bacillus subtilis. bamhi cleaved pub110 was introduced into the bamhi site of transposon tn3 and the resulting enlarged tn3 (tn2551) was transposed from pbe10 onto phage lambda and than to pmb9 (tc) and rsf1010(sm su) plasmids. restriction and heteroduplex analysis of pmb9 :: tn2551(pbe21) and rsf1010 :: :: tn2551(pbe32 ... | 1981 | 6273258 |
| beta protein of bacteriophage lambda promotes renaturation of dna. | the protein encoded by the red beta gene of bacteriophage lambda was found to promote reannealing of complementary single strands of dna. reannealing activity was optimal at ph 6.0 and required a divalent cation. a threshold temperature of at least 15 degrees c was necessary in order to detect activity. the reaction was linear with time for about 20 min, but the extent of reaction was dependent upon the amount of beta protein added. reannealing of complementary single strands was confirmed by me ... | 1981 | 6273399 |
| construction and characterization of a tufa-lacz fusion coding for an e. coli ef-tu-beta-galactosidase chimeric protein. | a new phage lambda cloning vector was constructed that has a single ecori site upstream from weakly expressed laci-z gene isolated by müller-hill and kania (1974). an ecori fragment containing the complete tufa gene of e. coli was cloned on the vector and the recombinant phage was crossed into the str operon that has tufa as its last gene. subsequent selection gave rise to a tufa-lacz fusion that codes for a chimeric peptide. the fused peptide has a molecular weight of 148,000 and contains 40% o ... | 1981 | 6276696 |
| the ral gene of phage lambda. i. identification of a non-essential gene that modulates restriction and modification in e. coli. | host controlled restriction in escherichia coli can be relieved by pre-infecting restricting cells with modified lambda helper phages. this process, in which intact unmodified phage genomes are allowed to escape restriction attack, is mediated by a newly identified lambda function called ral. the ral gene has been located by deletion mapping between ciii and n. efficient expression of the ral gene requires the product of the regulator gene n. polyacrylamide gel analysis of the lambda proteins sp ... | 1980 | 6256607 |
| molecular cloning and amplification of the gene for thymidylate synthetase of e. coli. | the thya gene of escherichia coli, which directs the synthesis of the enzyme thymidylate synthetase, has been subcloned from a recombinant lambda phage (hickson et al., 1982) into the multicopy plasmid pbr325 to give the plasmid ppe245. to identify the thya gene product, the transposon tn1000 was inserted into ppe245 and derivative plasmids isolated that were no longer able to complement thya mutations. when proteins synthesised by these plasmids and by ppe245 were labelled and analysed on sds-p ... | 1982 | 6290329 |
| abelson murine leukemia virus: structural requirements for transforming gene function. | the integrated abelson murine leukemia virus (a-mulv) genome cloned in bacteriophage lambda gtwes.lambda b was used to localize viral genetic sequences required for transformation. comparison of the biological activity of cloned a-mulv genomic and subgenomic fragments showed that subgenomic clones that lacked the 5' long terminal repeat and adjoining sequences (300 base pairs downstream of the repeat) were not biologically active. in contrast, subgenomic clones that lacked the 3' long terminal r ... | 1982 | 6291048 |
| escherichia coli plasmid vectors containing synthetic translational initiation sequences and ribosome binding sites fused with the lacz gene. | the construction of a series of escherichia coli plasmid vectors suitable for assaying the effects of gene control signals fused with the e. coli lacz gene is reported. a synthetic deoxyoligonucleotide dodecamer 5'-catgaattcatg gtacttaagtac-5' containing two translation initiation codons (atg) separated by an ecori site was ligated with a lacz gene derivative which lacks the codons for the first eight amino acids in plasmid pmc1403 (casadaban et al., 1980). two ribosome-binding sequences were sy ... | 1982 | 6293930 |
| localization of the metjblf gene cluster of escherichia coli in lambda met transducing phage. | the position of the metjblf gene cluster in the transducing phage lambda met102 was determined by ligation of its leftmost ecori fragment (102-1) to the lambda bcdef (nin5) ecori fragment of lambda gtl (lambda bc) and characterization of the resultant recombinant phage. the new transducing phage carries about 6kb of bacterial dna which contains the entire met gene cluster including the promoter of its rightmost member metf. reasonable estimates of the coding capacity required for the four genes ... | 1982 | 6294471 |
| probing cii and hima action at the integrase promoter pi of bacteriophage lambda. | plasmids were constructed to supply cii-coded protein for activation of the phage promoter pi. using a fusion which expresses lacz from pi. we can accurately follow activation of pi without having to assay int activity in vivo. a large excess of cii protein compared to a normal lytic infection stimulates lacz expression about 10-fold over the basal level. the int-c226 constitutive allele of pi is not further activated by cii even though its level of lacz expression is less than the maximal cii-a ... | 1982 | 6295882 |
| plasmid vectors capable of transferring large dna fragments to yeast. | we have constructed several cloning vectors which can be used in vitro packaging and yeast transformation. these plasmids have been designed for the convenient cloning of large segments of dna and their transfer to yeast. they contain bacterial plasmid dna sequences for replication and selection in escherichia coli, yeast 2-microns plasmid dna sequences or chromosomal replicators and yeast markers necessary for replication and selection in yeast, and the cohesive ends of bacteriophage lambda whi ... | 1981 | 6299664 |
| identification of sequences necessary for packaging dna into lambda phage heads. | several species of dna molecules are packaged into lambda phage heads if they carry the region around the cohesive end site of lambda phage (cos lambda). the minimal functional sequence around cos lambda needed for packaging was examined by cloning in pbr322. the results showed that the minimal region contained 85 bp around cos lambda; 45 bp of the left arm of lambda phage and 40 bp of the right arm. a 75-bp region located to the right of the minimal region seems to enhance packaging. a 223-bp f ... | 1982 | 6299893 |
| overproduction of the ecorii endonuclease and methylase by escherichia coli strains carrying recombinant plasmids constructed in vitro. | recombinant dna molecules were constructed from the plasmid pil203 and the ecori-fragment of n3 plasmid containing ecorii endonuclease and methylase genes and also a gene for resistance to sulfanilamide. the pil203 plasmid, used as a vector, consisted of the bam hi-ecori-fragment of the plasmid pbr322 conferring resistance to ampicillin and the bam hi-ecori-fragment of lambda phage containing promoters, a thermosensitive mutation in the ci gene and a suppressible amber mutation in the cro gene. ... | 1981 | 6266480 |
| site-specific recombination by gin of bacteriophage mu: inversions and deletions. | a 3000-bp invertible segment in the dna of bacteriophage mu determines the host range of the phage. the inversion is catalyzed by the phage-coded protein gin; the recombination sites are short inverted repeats. gin protein is only made in low amounts by mu. to further investigate the gin-mediated recombination reaction a gin overproducing strain was constructed. the gin gene was cloned on a plasmid behind the pl-promotor of phage lambda. this results in a 100-fold higher inversion frequency of a ... | 1983 | 6305017 |
| use of lambda phasmids for deletion mapping of non-selectable markers cloned in plasmids. | a nonselectable gene carried on a poorly selectable recombinant plasmid has been physically mapped by deletion analysis. our method involved cloning the plasmid into a coliphage lambda vector and treating the recombinant phage with a chelator. virtually all particles surviving this treatment carried large deletions within the plasmid insert. further deletion analysis was done by inserting a selectable lambda sequence into one such deletion derivative and repeating the chelator selection. chelato ... | 1983 | 6305773 |
| site-specific dna condensation and pairing mediated by the int protein of bacteriophage lambda. | the int protein of bacteriophage lambda catalyzes the site-specific integrative recombination that inserts lambda dna into the host chromosome. the attachment site region of lambda dna required for this reaction spans 230 base pairs and includes four separable binding sites for int protein. we have used the electron microscope to determine the functional consequences of the interaction of int with its multiple binding sites. we find that int condenses a 230-base pair segment of dna into a compac ... | 1982 | 6310548 |
| integration of viral dna into the genome of the adenovirus type 2-transformed hamster cell line he5 without loss or alteration of cellular nucleotides. | hamster cell line he5 has been established from primary lsh hamster embryo cells by transformation with adenovirus type 2 (ad2) (1). each cell contains two to three copies of integrated ad2 dna (2, 3). we cloned and sequenced the sites of junction between viral and cellular dnas. the terminal 10 and 8 nucleotides of ad2 dna were deleted at the left and right sites of junction, respectively. the integrated viral dna had an internal deletion between map units 35 and 82 on the ad2 genome. at the in ... | 1983 | 6316259 |
| mutations in the dna gyrb gene that are temperature sensitive for lambda site-specific recombination, mu growth, and plasmid maintenance. | we report the isolation of two mutations in the gyrb gene of escherichia coli k12 obtained from an initial selection for resistance to coumermycin a1 and a subsequent screening for bacteria that fail to support site-specific recombination of phage lambda, i.e., him-. these two mutations have a temperature-sensitive him- phenotype, supporting site-specific recombination efficiently at low temperature, but inefficiently at high temperatures. like other him mutants, the gyrb-him mutants fail to pla ... | 1984 | 6319362 |
| genetic analysis of clear-plaque mutations induced in bacteriophage lambda by 9-aminoacridine. | clear-plaque mutations were induced in the ci and cii genes of lambda by treating lysogenic cells with 9-aminoacridine (9aa). mapping of the mutations revealed that there were two hot spots for 9aa mutagenesis in ci, and one strong hot spot in cii. the hot spots in ci mapped close to 1 of the 3 runs of 4 g/c base-pairs and near the only run of 5 g/cs, respectively, in this gene. of 36 ci mutations tested, at most one mapped near a run of 6 a/t base-pairs. by analogy, the sequence responsible for ... | 1984 | 6239977 |
| mrna processing in escherichia coli: an activity encoded by the host processes bacteriophage f1 mrnas. | to examine the regions of the male-specific filamentous bacteriophage f1 genome that include signals for mrna processing, the 5' endpoints of the major in vivo phage mrnas have been located in the f1 dna sequence by s1 nuclease mapping. the 5' ends of the purified mrnas and additional phage-specific rnas transiently visible early after infection occur in clusters of t-rich residues within genes that code for three phage proteins. when a 270-nucleotide region encompassing the 5' endpoints of thre ... | 1984 | 6322124 |
| protein degradation in escherichia coli: the lon gene controls the stability of sula protein. | escherichia coli lon mutants are defective in the atp-dependent proteolysis of abnormal proteins. the mutants are also sensitive to ultraviolet light (uv) in that septation is inhibited after exposure to uv. sula mutations, isolated as suppressors of uv sensitivity unlinked to lon, do not affect proteolysis but allow septation to occur after dna damage. we have confirmed the hypothesis that the product of the sula gene is degraded by lon proteolysis. if sula (the product of sula) is a uv-inducib ... | 1983 | 6300834 |
| cloning and manipulation of the escherichia coli cyclopropane fatty acid synthase gene: physiological aspects of enzyme overproduction. | like many other eubacteria, cultures of escherichia coli accumulate cyclopropane fatty acids (cfas) at a well-defined stage of growth, due to the action of the cytoplasmic enzyme cfa synthase. we report the isolation of the putative structural gene, cfa, for this enzyme on an e. coli-cole1 chimeric plasmid by the use of an autoradiographic colony screening technique. when introduced into a variety of e. coli strains, this plasmid, plc18-11, induced corresponding increases in cfa content and cfa ... | 1984 | 6325391 |
| transcriptional termination sites in the b2 region of bacteriophage lambda that are unresponsive to antitermination. | a bacteriophage lambda cloning vector carrying the trp/lacw205 substitution is described. the vector facilitates the fusion in vitro of genetic control signals to the lacz structural gene of escherichia coli. this system was used to define transcriptional termination sites in the lambda b2 region. this region contains termination sites that are unresponsive to the lambda antiterminating proteins pq and pn. | 1982 | 6285144 |
| identification of the phom gene product and its regulation in escherichia coli k-12. | plasmids containing the chromosome region of escherichia coli encoding phom, whose product is a positive regulator of alkaline phosphatase expression, were isolated from the clarke and carbon plasmid bank. a 9.9-kilobase ecori fragment of plasmid plc17-39 (subcloned into pbr322) was able to complement both phom and thrb mutations. restriction endonuclease analysis and in vitro mutagenesis of the hybird plasmids enabled the localization of the phom gene locus to 3 kilobases of the cloned chromoso ... | 1984 | 6330029 |
| construction of a plasmid that overproduces the large proteolytic fragment (klenow fragment) of dna polymerase i of escherichia coli. | using currently available gene fusion techniques, we have constructed plasmids that direct the overproduction of the carboxyl-terminal two-thirds of dna polymerase i, corresponding to the proteolytically derived "klenow fragment." we have obtained overproduction amounting to several percent of the cellular protein using constructs in which expression is directed either from the lac promoter or from the leftward promoter of phage lambda. the polymerase fragment has been purified to homogeneity fr ... | 1983 | 6340110 |
| stabilization of proteins by a bacteriophage t4 gene cloned in escherichia coli. | the cloned bacteriophage t4 pin gene functions to stabilize several different kinds of proteins in escherichia coli bacteria. incomplete proteins such as puromycyl polypeptides, abnormal but complete proteins such as the lambda phage tso protein, and labile eukaryotic proteins encoded by genes cloned in e. coli such as mature human fibroblast interferon are stabilized in cells in which the t4 pin gene is expressed. the cloned t4 pin gene does not seem to affect the turnover of normal e. coli pro ... | 1983 | 6340113 |
| expression of cloned mitochondrial dna from the petite negative yeast schizosaccharomyces pombe in e. coli minicells. | the minicell producing escherichia coli strain d24 (lysogenic for phage lambda ci857) was transformed with the recombinant plasmid pdg3 containing the entire mitochondrial (mt) genome of the fission yeast schizosaccharomyces pombe (s. pombe) cloned in the single bamhi-site of the e. coli plasmid pbr322 (del giudice 1981). by dna-rna hybridization it could be shown that the total mtdna sequence of the plasmid pdg3 was transcribed in the e. coli minicells. the cloned mtdna also directed the synthe ... | 1983 | 6350830 |
| expression and regulation of protein k, an escherichia coli k1 porin, in escherichia coli k-12. | using a modified lambda phage as a vector and a procedure developed in dr. c. schnaitman's laboratory, we have cloned the structural gene for protein k from an escherichia coli k1 strain to an e coli k-12 strain. the cloned inserts consist of two hindiii fragments, 4 kb and 6.5 kb in size. the protein produced by the insert is nearly identical to "authentic" protein k when chymotryptic peptides of 125i-labeled proteins are compared. protein k was found to respond to changes in the osmolarity of ... | 1983 | 6373798 |
| [mutagenic effects of gamma-rays on plasmid dna in escherichia coli]. | a purified and dried dna of plasmid pko482 (galk+) is 10 times more resistant to the inactivating action of 60co-gamma-rays than that of lambda phage. gamma-irradiation of the plasmid dna induces forward mutations of galk, the frequency of which increases linearly with the dose. the efficiency of the mutagenic action of gamma-rays on the plasmid galk locus is 10(-12) per 1 rad and per 1 base pair. the mutagenic effect of gamma-radiation but slightly depends upon bacterial reca+ gene and upon the ... | 1984 | 6390494 |
| mapping of the glucose dehydrogenase gene in bacillus subtilis. | a 4.0-kilobase dna fragment containing the developmentally regulated gene for glucose dehydrogenase (gdh) from bacillus subtilis was incorporated into the plasmid pgx345, which contains a marker conferring chloramphenicol resistance (cat). the resistance marker of the resulting integration vector was used to map the gdh gene on the b. subtilis chromosome. using pbs1 transduction, the gene order was determined to be aroi cat (gdh) mtlb dal. the cat (gdh) marker was also cotransformable with mtlb. ... | 1984 | 6438057 |
| lambda placmu: a transposable derivative of bacteriophage lambda for creating lacz protein fusions in a single step. | we isolated a plaque-forming derivative of phage lambda, lambda placmu1 , that contains sequences from bacteriophage mu enabling it to integrate into the escherichia coli chromosome by means of the mu transposition system. the mu dna carried by this phage includes both attachment sites as well as the ci, ner (cii), and a genes. lambda placmu1 also contains the lacz gene, deleted for its transcription and translation initiation signals, and the lacy gene of e. coli, positioned next to the termina ... | 1984 | 6327627 |
| purification and characterization of the integration protein specified by bacteriophage lambda. | | 1980 | 6444632 |
| [adsorption of lambda phage dna onto escherichia coli cells treated with ca2+ ions and onto frozen--thawed bacteria]. | the study of the biologically active tritium-labeled phage lambda dna adosrption on ca2+-treated and frozen--thawed e. coli cells showed the absence of a correlation between the adsorption level and transfection efficiency. thus the infectious phage lambda dna adsorption level does not change, while frozing--thawing of e. coli cells but it increases ten-fold when treating the cells with ca2+ in ice, the transfection efficiency level with this dna being equal for both types of recipients. | 1980 | 6446330 |