Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| transcriptional activation of bacteriophage lambda dna replication in vitro: regulatory role of histone-like protein hu of escherichia coli. | initiation of bacteriophage lambda dna replication in vivo and in crude in vitro systems is strongly dependent on transcription at or near the lambda replication origin (ori lambda). through its capacity to prevent rna polymerase-mediated 'transcriptional activation' of lambda dna replication, the lambda ci repressor is capable of negatively regulating initiation of lambda dna replication, even when all required replication proteins are present. surprisingly, the strict requirement for transcrip ... | 1989 | 2529119 |
| high-level expression of active human cystatin c in escherichia coli. | expression of the human cysteine proteinase inhibitor, cystatin c (cysc) in the cytoplasm of escherichia coli was studied using a cdna fragment encoding the cysteine proteinase inhibitor controlled by the phage lambda pr/ci857 system. the yield of cysc was low, probably due to proteolytic degradation. by fusing the cysc cdna to a dna fragment encoding the signal peptide of the e. coli outer membrane protein a, it was possible to produce a substantial amount of cysc in the periplasm. the processi ... | 1989 | 2529167 |
| stability of the transformants obtained by phage particle-mediated gene transfer. | recombinant lambda phage dna, encapsulated in phage particles and coprecipitated with calcium phosphate, efficiently transforms cultured mammalian cells without a requirement for carrier dna. the present paper analyzes the stability of the transformants obtained by the phage transfer method. lambda phage particles containing recombinant dna that includes the thymidine kinase (tk) gene of herpes simplex virus type 1 as a selective marker were introduced into ltk- cells deficient in tk activity, a ... | 1989 | 2529979 |
| distribution of chi-stimulated recombinational exchanges and heteroduplex endpoints in phage lambda. | the recombination hotspot chi, 5' g-c-t-g-g-t-g-g 3', stimulates the recbcd recombination pathway of escherichia coli. we have determined, with precision greater than previously reported, the distribution of chi-stimulated exchanges around a chi site in phage lambda. crosses of lambda phages with single base-pair mutations surrounding a chi site were conducted in and analyzed on mismatch correction-impaired hosts to preserve heteroduplex mismatches for analysis. among phages recombinant for flan ... | 1989 | 2530132 |
| the rex genes of bacteriophage lambda can inhibit cell function without phage superinfection. | the rexa and rexb genes of bacteriophage lambda are expressed from the prophage and cause the exclusion of many superinfecting mutant phages. we cloned the rexa and rexb genes into a multicopy plasmid so that they were overexpressed from the inducible tac promoter. no obvious phenotypes were associated with overexpressing both rexa and rexb or overexpressing rexa in the absence of rexb expression. however, induction of rexa in the presence of limiting rexb activity caused an immediate cessation ... | 1989 | 2530135 |
| phasmids as effective and simple tools for construction and analysis of gene libraries. | phasmid lambda pmyf131, a hybrid of phage lambda vectors and plasmid puc19, was constructed. the phasmid and its derivatives were shown to be efficient vectors for construction and analysis of gene libraries in escherichia coli cells. the lambda pmyf131 dna molecule contains all the genes and regions essential for phage lytic development. the plasmid cannot be packaged either in the monomeric or the oligomeric form due to its specific length. elongation of the dna molecule by ligation with fragm ... | 1989 | 2530136 |
| cloning and expression in escherichia coli of the genes of the arginine deiminase system of streptococcus sanguis nctc 10904. | the common oral bacterium streptococcus sanguis can degrade arginine via the arginine deiminase (ad) system. the three enzymes of this system, ad, ornithine carbamyltransferase (otc), and carbamate kinase (ck), catalyze the breakdown of arginine to ornithine, co2, and two molecules of ammonia, with the production of atp from adp. the genes of the ad system, which are subject to complex regulation in the oral streptococci, have been isolated in bacteriophage lambda by screening for ad activity. t ... | 1989 | 2530176 |
| repression of the lambda pcin promoter by integrative host factor. | the cin-1 mutation creates a new promoter (pcin) in the tr1 region of bacteriophage lambda. the pcin promoter transcribes the ci repressor gene constitutively. lambda cin-1 does not propagate on escherichia coli mutants lacking the integrative host factor (ihf). lambda ci- cin-1 grows normally in ihf- mutants, indicating that repressor overproduction from pcin blocks lytic growth. the presence of an ihf binding site which overlaps the pcin promoter led us to the hypothesis that ihf functions as ... | 1989 | 2530356 |
| efficient rescue of integrated shuttle vectors from transgenic mice: a model for studying mutations in vivo. | to study gene mutations in different organs and tissues of an experimental animal, we produced transgenic mice harboring bacteriophage lambda shuttle vectors integrated in the genome in a head-to-tail arrangement. as a target for mutagenesis, the selectable bacterial lacz gene was cloned in the vector. the integrated vectors were rescued from total genomic dna with high efficiency by in vitro packaging and propagation of the phages in a lacz- strain of escherichia coli c. the background mutation ... | 1989 | 2530578 |
| construction of a modified murine interferon alpha with increased stability. | the mutant [ser86] murine interferon alpha a was constructed by oligodeoxyribonucleotide-directed site-specific mutagenesis and expressed under the control of lambda phage pl promoter in escherichia coli. the effect of the substitution of serine for the cysteine residue at position 86 in the murine interferon alpha a was studied. it was observed that the mutant ser86 murine interferon alpha a which does not contain the free cysteine residue in the peptide was inactivated more slowly than its par ... | 1989 | 2530803 |
| [structure of the recombination zone during abnormal excision of the transducing bacteriophage lambda plac9]. | investigating molecular mechanism of illegitimate recombinations in prokaryote we study transducing bacteriophages of the lambda lac series. we have carried out physical mapping of bacteriophage lambda plac9 dna and, by comparing the obtained results with the data on the structure of lambda dna and lac operon of e. coli, located the phage-bacterial junction corresponding to the lambda-lac9 abnormal excision and elucidated the nucleotide sequence around the junction. it led to the primary structu ... | 1989 | 2530989 |
| characterization of the dna-dna cross-linking activity of 3'-(3-cyano-4-morpholinyl)-3'-deaminoadriamycin. | 3'-(3-cyano-4-morpholinyl)-3'-deaminoadriamycin (cma) is a highly potent analogue of the antitumor agent, adriamycin (adr), being up to 1500 times more cytotoxic both in vivo and in vitro. in contrast to adr, cma, and 5-imino-3'-(3-cyano-4-morpholinyl)-3'-deaminoadriamycin (icma) have been shown to possess alkylating activity, as seen by their ability to produce dna-dna cross-links in human and murine tumor cells and in isolated lambda-phage dna. we have compared the pharmacological activities o ... | 1989 | 2531036 |
| dual translational initiation sites control function of the lambda s gene. | lysis gene s of phage lambda has a 107 codon reading frame beginning with the codons met1-lys2-met3. genetic data have suggested that translational initiation occurs at both met1 and met3, generating two polypeptides, s107 and s105 respectively. we have proposed a model in which the proper scheduling of lysis depends on the partition of translational initiations between the two start codons. here, using in vitro methods, we show that two stem-loop structures, one immediately upstream of the read ... | 1989 | 2531079 |
| interaction between the sbcc gene of escherichia coli and the gam gene of phage lambda. | gam mutants of phage lambda carrying long palindromes fail to form plaques on wild-type escherichia coli but do grow on strains that are mutant in the sbcc gene. gam + lambda carrying the same palindrome grow on both hosts and on a host deleted for the recb, c and d genes. these results suggest that the gam protein of lambda, known to interact also with e. coli's recbcd protein, can interact with the product of the sbcc gene. | 1989 | 2531105 |
| phage particle-mediated gene transfer of recombinant cosmids to cultured mammalian cells. | an efficient procedure for the introduction of recombinant cosmids into cultured mammalian cells consists of the following steps. cosmids were packaged, in vitro, into lambda phage particles and transduced into escherichia coli hosts lysogenized with thermo-inducible lambda c its phage. the introduced cosmids were repackaged into phage particles in the thermo-induced hosts. the efficiency of such in vivo cosmid packaging was further improved by construction of ptc vectors that carried three cohe ... | 1989 | 2531106 |
| [thermo-regulated expression of the htpr gene under the control of the pr-promotor of bacteriophage lambda induces supersynthesis of heat shock proteins]. | the mechanisms of induction of heat shock protein synthesis in e. coli have been studied. for this purpose plasmids in which htpr gene expression is controlled by the pr-promoter of bacteriophage lambda and by the trp-promoter have been constructed. an effective induction of heat shock proteins requires both an increased content of htpr protein and additional cofactors formed in the cell under heat shock conditions. | 1989 | 2531273 |
| improved cdna cloning into bacteriophage lambda gt11. | 1989 | 2531373 | |
| generation of a large combinatorial library of the immunoglobulin repertoire in phage lambda. | a novel bacteriophage lambda vector system was used to express in escherichia coli a combinatorial library of fab fragments of the mouse antibody repertoire. the system allows rapid and easy identification of monoclonal fab fragments in a form suitable for genetic manipulation. it was possible to generate, in 2 weeks, large numbers of monoclonal fab fragments against a transition state analog hapten. the methods described may supersede present-day hybridoma technology and facilitate the producti ... | 1989 | 2531466 |
| overproduction of truncated subunit a of h+-atpase causes growth inhibition of escherichia coli. | genes (uncb) for wild-type and mutant a subunits of escherichia coli h+-atpase (f0f1) were cloned into recombinant plasmids. the subunits were expressed under the control of a weak promoter of the unc operon at 30 degrees c and strong promoters of lambda phage at 42 degrees c. at 30 degrees c, the wild type and a truncated (glu-269----end) a subunit complemented the defect of the a subunit mutant kf24a (trp-111----end), whereas the other mutant subunits (trp-111----end, trp-231----end, gln-252-- ... | 1989 | 2531735 |
| alternative mrna structures of the ciii gene of bacteriophage lambda determine the rate of its translation initiation. | the bacteriophage lambda ciii gene product has a regulatory function in the lysis-lysogeny decision following infection. the availability of a set of ciii expression mutants allowed us to establish the structure-function relationship of the ciii mrna. we demonstrate, using defined in vitro systems, that the ciii mrna is present in two conformations at equilibrium. mutations that have been shown to lead to ciii overexpression were found to freeze the rna in one conformation (structure b), and per ... | 1989 | 2532257 |
| a rapid method for determining the orientation of inserts in bacteriophage lambda vectors. | 1989 | 2532323 | |
| human thymidylate synthase gene: isolation of phage clones which cover a functionally active gene and structural analysis of the region upstream from the translation initiation codon. | two genomic dna fragments partially encoding human thymidylate synthase (ts) [ec 2.1.1.45] were previously cloned in lambda phage from the mouse cell transformant, but had no transforming activity on mouse ts-negative mutant cells. in this study, an additional genomic dna for human ts was cloned and demonstrated to have the transforming activity in combination with one of the two previously cloned dnas and to produce human ts mrna. the two transforming genomic dnas overlapped and covered a regio ... | 1989 | 2532645 |
| the terminus of the escherichia coli chromosome is flanked by several polar replication pause sites. | replication of two small 'constrained' regions of the escherichia coli chromosome, one bordered by replication terminator t1 and the other by t2, displays normal velocity in the normal direction whereas it is much slower in the opposite direction (de massy et al., 1987). the presence of multiple polar terminators has been investigated, using a bacteriophage lambda derivative which provides a replication origin movable to predetermined loci and inducible on demand. the amount of dna made from thi ... | 1989 | 2532703 |
| study on the function of the bent dna within adenovirus type 2 eia enhancer: analysis using an in vitro transcription system. | the role of the bent dna within human adenovirus type 2 (ad2) enhancer in transcriptional activation of e1a gene has been investigated. the bent region of the enhancer was substituted by a straight dna fragment or by a bent dna fragment of 194 bp from origin region of phage lambda replication. employing an in vitro transcription system using hela cell extract, effects of mutant enhancers on e1a gene transcription were analyzed. the results obtained showed that the amount of transcripts is affect ... | 1989 | 2532737 |
| bending of dna by gene-regulatory proteins: construction and use of a dna bending vector. | the binding of a protein to its specific sequence, borne on a dna fragment, retards the mobility of the fragment in a characteristic way during gel electrophoresis. if the protein induces bending in the dna, the contortion can also be monitored by gel electrophoresis, because the amount of retardation of the mobility of the dna-protein complex is dependent upon the position and the degree of the bend induced in the dna fragment [wu and crothers, nature 308 (1984) 509-513]. we have constructed a ... | 1989 | 2533576 |
| a convenient moderate-scale procedure for obtaining dna from bacteriophage lambda. | 1989 | 2534273 | |
| sequencing of cloned dna using bacteriophage lambda gt11 templates. | a procedure for isolating and directly sequencing recombinant bacteriophage lambda gt11 dna templates is described. approximately 250-300 bases of sequence can be obtained directly from the lambda gt11 template, eliminating the need for subcloning prior to dideoxynucleotide sequencing of clones. | 1989 | 2534351 |
| a reliable method for the purification of bacteriophage lambda dna. | 1989 | 2534352 | |
| genetic analysis of the n transcription antitermination system of phage lambda. | regulation of coliphage lambda gene expression occurs, in part, by a process of termination and antitermination of transcription. the n gene product, one of two lambda encoded antitermination proteins, acts with host encoded proteins, nus, at sites, nut, located downstream of the early promoters to render the transcribing rna polymerase resistant to many downstream termination signals. we discuss the nature of some of the proteins and sites involved in this process. | 1989 | 2534385 |
| homologous recombination in prokaryotes: enzymes and controlling sites. | a common step in prokaryotic recombination appears to be the synapsis of the 3'-end of single-stranded dna with duplex dna to form a d-loop. the enzymatic mechanisms by which 3'-ends are produced and by which d-loops are converted into recombinant molecules are illustrated by proposed mechanisms of recombination by the escherichia coli recbcd pathway and the phage lambda red pathway. the enzymes promoting recombination and the special dna sites at which they act are emphasized. recombination by ... | 1989 | 2534386 |
| a hybrid mode of rotating gel electrophoresis for separating linear and circular duplex dna. | during agarose gel electrophoresis, alternately applying the electrical potential gradient (e) in two directions (separated by an angle, psi) has been used to enhance the separation by length of linear, double-stranded dna; the value of psi is usually between 0.5 pi and 0.7 pi radians (cantor et al. (1988). ann. rev. biophys. biophys. chem. 17, 287-304). when the direction of e is changed by rotating the gel (rotating gel electrophoresis, or rge), open circular dna longer than 48 kb is found her ... | 1989 | 2535118 |
| reconstitution of a nine-protein system that initiates bacteriophage lambda dna replication. | we have established an in vitro system, composed of highly purified bacteriophage lambda and escherichia coli proteins, that specifically replicates supercoiled templates bearing the lambda replication origin (ori lambda). the complete system is composed of three groups of proteins: the virus-encoded initiator proteins (the lambda o and p proteins), the e. coli replication fork propagation machinery (single-stranded dna-binding protein, dnab helicase, dnag primase, dna polymerase iii holoenzyme, ... | 1989 | 2536726 |
| specificity of the interaction of furfural with dna. | furfural or 2-furaldehyde is a dietary mutagen and is present in various frequently consumed food products. the alkaline unwinding assay and protection of cleavage sites from the action of various restriction enzymes was used to study the interaction of furfural with dna. alkaline unwinding experiments showed the formation of an increasing number of strand breaks in duplex dna both with increasing furfural concentration and with time of reaction. treatment of lambda phage dna with furfural prote ... | 1989 | 2538745 |
| cloning and expression of the streptococcal c5a peptidase gene in escherichia coli: linkage to the type 12 m protein gene. | a genomic library of streptococcus pyogenes cs24 dna was constructed by cloning streptococcal dna partially digested with sau3a into the lambda replacement vector embl3. the expression of streptococcal c5a peptidase (scp) was analyzed by radioimmunoassay with hyperimmune rabbit serum. two clones, lambda 4.1 and lambda 4.2, were found to express the desired antigen, and various dna fragments from the hybrid bacteriophage lambda 4.1 were subcloned into the plasmid vector puc9 in escherichia coli. ... | 1989 | 2542163 |
| suppression of reca deficiency in plasmid recombination by bacteriophage lambda beta protein in recbcd- exoi- escherichia coli cells. | plasmid recombination, like other homologous recombination in escherichia coli, requires reca protein in most conditions. we have found that the plasmid recombination defect in a reca mutant can be efficiently suppressed by the beta protein of bacteriophage lambda. beta protein is required for homologous recombination of lambda chromosomes during lytic phage growth in a reca host and is known to have a strand-annealing activity resembling that of reca protein. the bioluminescence recombination a ... | 1989 | 2542228 |
| vaccinia dna topoisomerase i promotes illegitimate recombination in escherichia coli. | vaccinia virus encapsidates a mr 32,000 type idna topoisomerase. although the vaccinia gene encoding the topoisomerase is essential for virus growth, the role of the enzyme in vivo remains unclear. in the present study, the physiologic consequences of vaccinia topoisomerase action have been examined in a heterologous system, escherichia coli. the vaccinia topoisomerase gene was inducibly expressed in an int-lambda lysogen bl21(de3) using a t7 rna polymerase-based transcription system. expression ... | 1989 | 2542933 |
| heat shock protein-mediated disassembly of nucleoprotein structures is required for the initiation of bacteriophage lambda dna replication. | three escherichia coli heat shock proteins, dnaj, dnak, and grpe, are required for replication of the bacteriophage lambda chromosome in vivo. we show that the grpe heat shock protein is not required for initiation of lambda dna replication in vitro when the concentration of dnak is sufficiently high. grpe does, however, greatly potentiate the action of dnak in the initiation process when the dnak concentration is reduced to a subsaturating level. we demonstrate in the accompanying articles (alf ... | 1989 | 2543679 |
| dna looping generated by dna bending protein ihf and the two domains of lambda integrase. | the multiprotein-dna complexes that participate in bacteriophage lambda site-specific recombination were used to study the combined effect of protein-induced bending and protein-mediated looping of dna. the protein integrase (int) is a monomer with two autonomous dna binding domains of different sequence specificity. stimulation of int binding and cleavage at the low affinity core-type dna sites required interactions with the high affinity arm-type sites and depended on simultaneous binding of t ... | 1989 | 2544029 |
| topoisomerase ii-mediated dna cleavage activity induced by ellipticines on the human tumor cell line n417. | ellipticine derivatives have been shown to induce dna strand breaks by trapping dna-topoisomerase ii (topo ii) in an intermediary covalent complex between topo ii and dna which could be related to their cytotoxic effects. we report here that celiptium and detalliptinium, two ellipticine derivatives clinically used for their antitumoral properties against breast cancer, exhibit the highest in vitro activity on topo ii dna cleavage reaction and decatenation among a series of 14 ellipticine derivat ... | 1989 | 2544183 |
| [complete assignment of signals in 1d and 2d h-nmr spectra of a 17-member oligonucleotide, a model symmetrical analog of lambda operators]. | a synthetic analog of lambda phage operators, a symmetric duplex of oligonucleotides, was studied by 1h nmr at 400 mhz. signals in the spectrum of imino protons of the duplex in h2o were assigned based on the results of noe experiments and temperature dependences. resonance assignment of the non-exchangeable protons of bases and deoxyribose was performed by analysing the noesy spectrum obtained in the single experiment. the results indicate that the major part of the duplex has a conformation si ... | 1989 | 2544793 |
| expression in bacteria of functional inhibitory subunit of retinal rod cgmp phosphodiesterase. | the cgmp phosphodiesterase of vertebrate retinal rod outer segments plays a key role in visual transduction. a functionally active form of the inhibitory gamma subunit of the phosphodiesterase, which keeps the enzyme inactive in the dark, has been obtained in high yield from a synthetic gene expressed in escherichia coli. a dna sequence encoding the 87-residue bovine gamma subunit was chemically synthesized and assembled from 10 oligonucleotides. the synthetic gene was cloned into an expression ... | 1989 | 2544882 |
| [characteristics of escherichia coli k-12 mutants with altered effectiveness of excision of tn5 and tn9 transposons]. | the properties of escherichia coli k-12 mutans hfetn5, hfetn9 and lfetn9 have been studied. the majority of mutations were shown to have pleiotropic effect. some of them increase cell sensitivity to uv light and mitomycin c and affect efficiency of homologous recombination in transduction and conjugation. the level of spontaneous mutagenesis is increased in a number of mutants. none of the mutations isolated affect frequency of transposition of tn5 from bacteriophage lambda::tn5 into the chromos ... | 1989 | 2545521 |
| overproduction and preliminary crystallographic study of ribonuclease h from escherichia coli. | to facilitate the preparation of ribonuclease h from escherichia coli in an amount sufficient for crystallographic studies, we have constructed an overproduction system for the enzyme. the structural gene for the enzyme was subcloned from psk750 (kanaya, s., and crouch, r. j. (1983) j. biol. chem. 258, 1276-1281) to make a plasmid vector ppl801, in which the gene was under the control of bacteriophage lambda pl promoter. thermal induction of the gene accumulated the enzyme in e. coli n4830-1 to ... | 1989 | 2545673 |
| cloning and dna sequence of plasmid determinant iss, coding for increased serum survival and surface exclusion, which has homology with lambda dna. | escherichia coli k12 cells carrying a cloned 1.4 kb hindiii fragment from plasmid colv2-k94, showed increased survival in guinea pig serum. the recombinant plasmid also conferred group ii surface exclusion, i.e. the cells were reduced in recipient ability towards the incoming plasmid r538drd in conjugation experiments. southern blotting suggested homology with bacteriophage lambda dna and to the insertion element is2. determination of the dna sequence of the fragment demonstrated the presence of ... | 1989 | 2546040 |
| the human lysozyme gene. sequence organization and chromosomal localization. | we have isolated two overlapping recombinant lambda-phage clones from a genomic lambda-embl3 library containing 25 kb of the human lysozyme gene region. furthermore a full-lenght human lysozyme cdna clone of 1.5 kb was isolated from a human placenta cdna library. nucleotide sequences of the entire structural gene and the cdna clone were determined. the human lysozyme gene spans 5856 bp and its sequence organization with four exons and three introns is homologous to the chicken lysozyme gene and ... | 1989 | 2546758 |
| [deletion-insertion mapping of the region non-essential for functioning of the beta-subunit of escherichia coli rna polymerase]. | a plasmid has been constructed containing the gene of beta-subunit of rna polymerase of escherichia coli under control of the pr promoter of bacteriophage lambda. pr promoter may be induced by heating up to 42 degrees c. in frame insertions of different sequences between 989 and 990 or 1010 and 1011 codons of the rpob gene do not inactivate the beta-subunit function. deletions in the region of 1011-1027 codons result in inactivation of beta-subunit. we localized antigene determinant of monoclona ... | 1989 | 2547695 |
| the escherichia coli protein, fis: specific binding to the ends of phage mu dna and modulation of phage growth. | we show, using gel retardation, that crude escherichia coli cell extracts contain a protein which binds specifically to dna fragments carrying either end of the phage mu genome. we have identified this protein as fis, a factor involved in several site-specific recombinational switches. furthermore, we show that induction of a mucts62 prophage in a fis lysogen occurs at a lower temperature than that of a wild-type strain, and that spontaneous induction of mucts62 is increased in the fis mutant. d ... | 1989 | 2548061 |
| mutational specificity studies of endogenous mammalian cell loci: methodological aspects. | we report here the details of a modified cloning method first described by seed et al. (1983) for use in an extensive study of mutational specificity at the aprt locus of chinese hamster ovary cells. the technology depends on homologous recombination between a suppressor probe plasmid and the desired insert in a genomic library constructed in a double amber mutant bacteriophage lambda vector. recombinant phage form blue plaques on a non-suppressor, lacz amber host. we have determined the sensiti ... | 1989 | 2548093 |
| tn5supf, a 264-base-pair transposon derived from tn5 for insertion mutagenesis and sequencing dnas cloned in phage lambda. | we constructed a derivative of transposon tn5 called tn5supf for insertion mutagenesis and sequencing dnas cloned in phage lambda. this element carries a supf amber-suppressor trna gene. its insertion into lambda can be selected by plaque formation by using nonsuppressing (sup0) escherichia coli for amber mutant lambda phage and sup0 dnab-amber e. coli for nonamber lambda phage. tn5supf is just 264 base pairs long. it transposes efficiently and inserts quasi-randomly into dna targets. the unique ... | 1989 | 2548192 |
| discovery of a protein phosphatase activity encoded in the genome of bacteriophage lambda. probable identity with open reading frame 221. | infection of escherichia coli with phage lambda gt10 resulted in the appearance of a protein phosphatase with activity towards 32p-labelled casein. activity reached a maximum near the point of cell lysis and declined thereafter. the phosphatase was stimulated 30-fold by mn2+, while mg2+ and ca2+ were much less effective. activity was unaffected by inhibitors 1 and 2, okadaic acid, calmodulin and trifluoperazine, distinguishing it from the major serine/threonine-specific protein phosphatases of e ... | 1989 | 2548489 |
| nick translation of lambda phage dna with a deoxycytidine analog spin labeled in the 5 position. | the synthesis and properties of a novel c(5)-spin-labeled 2'-deoxycytidine 5'-triphosphate which serves as a suitable substrate for the template-directed enzyme escherichia coli dna polymerase i are reported. the spin label is readily incorporated into lambda phage dna by nick translation where it reports the characteristic local base motion for double- and single-stranded dna as determined by electron spin resonance. the high-frequency deoxycytidine motion is similar to the previously reported ... | 1989 | 2549877 |
| effect of base pair mismatches on recombination via the recbcd pathway. | the effect of base pair mismatches on recombination via the recbcd pathway was studied in muts and wild-type escherichia coli, using substrates that contain single or multiple mismatches. recombination between homologous dna inserts in lambda phage and pbr322-derived plasmids forms phage-plasmid cointegrates that result from an odd numbers of crossovers. in the muts host, when the sequence homology of a pair of 405 bp substrates decreased from 100% to 89%, the recombinant frequency decreased by ... | 1989 | 2550771 |
| specific high frequency rearrangements induced by mnng in sv40-infected human keratinocytes. | in order to study carcinogen-induced changes in integrated viral sequences clonal sublines of sv40-transformed human keratinocytes were exposed to n-methyl-n'-nitro-n-nitrosoguanidine (mnng) at sublethal concentrations ranging up to 10 micrograms/ml for a period of 15 min and then examined by southern blot hybridization using full-length sv40 dna as a probe. of the clonal sublines tested, one (ag34) was found to exhibit certain consistent, dose-dependent changes at 4 days post-treatment: (i) los ... | 1989 | 2551523 |
| molecular characterization of two proteins involved in the excision of the conjugative transposon tn1545: homologies with other site-specific recombinases. | excision is probably the initial and rate-limiting step of the movements of conjugative transposons of gram-positive bacteria such as tn916 and tn1545. we have shown, by molecular cloning and dna sequencing, that a 2058 bp sau3a right-junction fragment of transposon tn1545 specifies two gene products that are involved in the excision of the element. the dna sequence of these genes, designated orf1 and orf2, has been determined and the corresponding proteins, orf1 and orf2, have been identified i ... | 1989 | 2551683 |
| new derivatives of transposon tn5 suitable for mobilization of replicons, generation of operon fusions and induction of genes in gram-negative bacteria. | three types of new variants of the broad-host-range transposon tn5 are described. (i) tn5-mob derivatives with the new selective resistance (r) markers gmr, spr and tcr facilitate the efficient mobilization of replicons within a wide range of gram-negative bacteria. (ii) promoter probe transposons carry the promoterless reporter genes lacz, nptii, or luc, and nmr, gmr or tcr as selective markers. these transposons can be used to generate transcriptional fusions upon insertion, thus facilitating ... | 1989 | 2551782 |
| physical and biological consequences of interactions between integration host factor (ihf) and coliphage lambda late p'r promoter and its mutants. | the integration host factor (ihf) binds to a site (ihf) that overlaps the -35 region of the phage lambda late rightward promoter (p'r). this interaction represses p'r-promoted transcription, both in vivo and in vitro. in vivo repression was observed when a plasmid carrying both p'r and the galk reporter gene was transfected into ihf+ or ihf- hosts. in vitro repression of transcription by ihf was observed only with linear, but not with supercoiled wild-type p'r templates. when binding to ihf, ihf ... | 1989 | 2553535 |
| characterization of the cryptic lambdoid prophage dlp12 of escherichia coli and overlap of the dlp12 integrase gene with the trna gene argu. | the argu (dnay) gene of escherichia coli is located, in clockwise orientation, at 577.5 kilobases (kb) on the chromosome physical map. there was a cryptic prophage spanning the 2 kb immediately downstream of argu that consisted of sequences similar to the phage p22 int gene, a portion of the p22 xis gene, and portions of the exo, p, and ren genes of bacteriophage lambda. this cryptic prophage was designated dlp12, for defective lambdoid prophage at 12 min. immediately clockwise of dlp12 was the ... | 1989 | 2553674 |
| analysis of bordetella pertussis virulence gene regulation by use of transcriptional fusions in escherichia coli. | the virulence regulon of bordetella pertussis includes a trans-acting regulatory locus, bvg, that is required for expression of several virulence factors. the virulence control system also responds to environmental signals. we have reconstructed a bvg-dependent regulatory system in escherichia coli by using bacteriophage lambda vectors carrying transcriptional fusions to laczya. single-copy laczya fusions to the b. pertussis fhab locus, which encodes the attachment factor filamentous hemagglutin ... | 1989 | 2553678 |
| mapping of insertion elements is1, is2 and is3 on the escherichia coli k-12 chromosome. role of the insertion elements in formation of hfrs and f' factors and in rearrangement of bacterial chromosomes. | the chromosome of an escherichia coli k-12 strain w3110 contains seven copies of insertion element is1, 12 copies of is2 and six copies of is3. we determined the approximate locations of six copies of is1 (named is1a to is1f), ten copies of is2 (named is2a to is2j), and five copies of is3 (named is3a to is3e) on the w3110 chromosome by plaque hybridization using the "mini-set" of the lambda phage library that includes 476 clones carrying chromosomal segments that cover the w3110 chromosome almos ... | 1989 | 2553981 |
| "activated"-reca protein affinity chromatography of lexa repressor and other sos-regulated proteins. | we have developed an affinity column to study the interaction of lexa repressor and other substrates with the activated form of reca protein. nucleoprotein complexes of reca protein, (dt)25-30, and adenosine 5'-[gamma-s]thio-triphosphate were formed in solution and bound to reca protein-agarose columns. these "activated"-reca nucleoprotein complexes were retained by strong hydrophobic interactions. purified lexa protein bound tightly to these activated reca columns, whereas the lexa protein boun ... | 1989 | 2554312 |
| episomal hpv 16 dna isolated from a cervical carcinoma presents a partial duplication of the early region. | an invasive cervical carcinoma was found to harbor an episomal variant of human papillomavirus (hpv) type 16 dna, with a size of about 10.1 kb. a genomic library of the tumor was constructed in bacteriophage lambda and a recombinant phage clone was isolated by screening with hpv 16 probe. analysis by restriction mapping and southern hybridization showed that the isolate contained a 2.2 kb duplication of the early region, which included part of e6, all e7 and part of e1 open reading frames. possi ... | 1989 | 2554613 |
| rapid isolation of high-molecular-weight dna from agarose gels. | we have developed a simple, reliable, and rapid method for recovering dna from agarose gels. while many methods for dna extraction have already been described, few provide quantitative recovery of large dna molecules. these procedures generally require costly apparatus, extended elution times, or considerable handling of the sample after elution. our method employs a novel electroelution chamber constructed from acrylic plastic. gel slices containing dna are placed in the chamber between platinu ... | 1989 | 2554757 |
| heteroduplex substrates for bacteriophage lambda site-specific recombination: cleavage and strand transfer products. | lambda's int protein acts as a specific topoisomerase at attachment sites, the dna segments that are required for site-specific recombination. int cleaves each strand of an attachment site at a unique place and creates strand exchanges by joining broken ends from two different parents. to study the action of int topoisomerase in more detail, heteroduplex attachment sites were made by annealing strands that are complementary except for a few base pairs that lie in the region between the points of ... | 1989 | 2555168 |
| bacteriophage lambda-mediated transposon mutagenesis of phytopathogenic and epiphytic erwinia species is strain dependent. | using transformation and conjugal mobilization, plasmids carrying the lamb gene of escherichia coli were transferred to a range of erwinia strains. the resultant strains were infected with lambda 467, and kanamycin resistant transductants were screened for various mutant phenotypes including auxotrophy and altered extracellular enzyme activities. reversion analysis suggested that most mutant phenotypes were due to tn5 insertion. the applicability of the techniques was highly strain dependent. ho ... | 1989 | 2555669 |
| recombination of bacteriophage lambda in recd mutants of escherichia coli. | recbcd enzyme is centrally important in homologous recombination in escherichia coli and is the source of exov activity. null alleles of either the recb or the recc genes, which encode the b and c subunits, respectively, manifest no recombination and none of the nuclease functions characteristic of the holoenzyme. loss of the d subunit, by a recd mutation, likewise results in loss of exov activity. however, mutants lacking the d subunit are competent for homologous recombination. we report that ... | 1989 | 2556327 |
| exometh sequencing of dna: eliminating the need for subcloning and oligonucleotide primers. | a method is reported for sequencing dna based on exonuclease iii digestion and strand protection by using modified nucleoside triphosphates. up to 10 kilobases of sequence information may be obtained from each strand of a given template without subcloning. prior knowledge of the restriction map is not important; prior knowledge of any of the sequence is not required. nor are oligonucleotide primers needed. double-stranded cosmids, plasmids, lambda phage, or linear molecules (including amplified ... | 1989 | 2556705 |
| long-range activation of transcription by sv40 enhancer is affected by "inhibitory" or "permissive" dna sequences between enhancer and promoter. | the transcriptional enhancer effect is used in many, if not all, organisms for remote control of gene transcription. an enhancer dna can dramatically stimulate transcription of a linked gene from positions either 5' or 3' to the gene. both the proximal promoter and the distal enhancer sequences are binding sites for transcription factors. interaction between promoter and enhancer is mediated by these factors, presumably via looping out of the intervening dna. here we report that the extent of re ... | 1989 | 2556801 |
| a simple and rapid method for the isolation of plasmid and lambda phage dnas. | 1989 | 2557581 | |
| isolation of a cdna clone of the 14-kda subunit of the signal recognition particle by cross-hybridization of differently primed polymerase chain reactions. | using an enhancement of the polymerase chain reaction (pcr) technique, we have isolated a complementary dna encoding srp14 (14-kda subunit), one of six proteins contained in the signal recognition particle (srp). several pools of degenerate oligonucleotides encoding different peptide sequences of srp14 were used to generate amplified dna by the pcr. a cross-hybridization procedure was developed to identify the authentic srp14 cdna clone among the amplified dna products obtained by pcr. the basis ... | 1989 | 2557625 |
| molecular cloning and nucleotide sequence of a cdna encoding euglena gracilis cytochrome c1. | the amino acid sequence of the mature protein of euglena gracilis cytochrome c1 was determined by sequencing of its cdna. a cdna expression library was constructed from euglena poly(a)+ rna in phage lambda gt11 and screened with an antiserum raised against cytochrome c1 polypeptide isolated from purified e. gracilis complex iii. an isolated cdna clone consisted of 872 base pairs and encoded the mature protein with 243 amino acids. the deduced amino acid sequence contained the unusual heme bindin ... | 1989 | 2558110 |
| substrate properties of 25-nt parallel-stranded linear dna duplexes. | four 25-nt oligonucleotides consisting of sequences of da and dt (d1-4) have been synthesized. as shown in a companion paper (rippe et al., 1989), the two combinations d1.d3 and d2.d4 form normal antiparallel duplexes, whereas the pairs d1.d2 and d3.d4 constitute duplexes with the same sequences, but with the two strands parallel to each other. the activities of the following dna processing enzymes and chemical reagents on the parallel stranded (ps) and antiparallel stranded (aps) duplexes were ... | 1989 | 2558723 |
| specificity and mechanism of antitermination by q proteins of bacteriophages lambda and 82. | lambdoid phage late gene operons are positively regulated by genome-specific antiterminator proteins encoded by the q gene of each phage. in this paper, we compare the activity of phage lambda and phage 82 q proteins. q82-mediated antitermination, like that of q lambda, involves a transcription pause during which the regulator can modify rna polymerase. we show that the activities of both q82 and q lambda are genome-specific in chasing rna polymerase out of the early pause sites and in mediating ... | 1989 | 2559206 |
| location and molecular cloning of the structural gene for the deoxyguanosine triphosphate triphosphohydrolase of escherichia coli. | the structural gene for deoxyguanosine triphosphate triphosphohydrolase (dgtpase) (ec 3.1.5.1) and its regulator, opta, have been located on a lambda phage carrying a 17.5kb escherichia coli dna insert. the dna fragment has been excised and ligated into pbr325 and also transferred to another lambda vector. from the results of transduction and transformation experiments, we find that the structural gene for dgtpase is very closely linked to opta and dapd, which locates it at approximately 3.6 min ... | 1989 | 2559296 |
| sumo15a: a lambda phasmid that permits easy selection for and against cloned inserts. | we report the construction of a phasmid vector, sumo15a, designed for recombination-based screening of recombinant dna libraries [seed, nucleic acids res. 11 (1983) 2427-2445]. this vector permits rapid selection in escherichia coli for homology-mediated integration and excision between homologous dna inserts cloned in a supf-carrying plasmid and in sumo15a. the region available for recombination spans the homologous sequence shared by the plasmid and the phasmid. supf is the selection tool that ... | 1989 | 2559877 |
| saturation mutagenesis of the inside end of insertion sequence is50. | a 19-bp segment at the inside (i) end of is50 (tn5) is needed for efficient transposition. the importance of each position was assayed by making at least one base substitution at each position by either chemical-or oligodeoxyribonucleotide-directed mutagenesis. mutant i ends were paired with a wild-type (wt) segment from the outside (o) end of is50 and the transposase (tnp) gene was placed either between the ends or 1200 bp from the o end. the frequency of transposition of the resultant elements ... | 1989 | 2559878 |
| [study on molecular hybridization with biotin-labelled hpv 16 dna probe in human cervical carcinoma]. | biotin-labelled human papillomavirus (hpv) 16 type dna probe was prepared by the techniques of molecular biology. and dot hybridization technique was used to detect the hpv 16 homologous sequences in the tissues dna of human cervical carcinoma. the results indicated that 16 cases out of 28 of the human cervical carcinoma tissues were positive. the positive rate was 57%. the other 4 cases of normal uterine cervix tissues were negative. only 1 in 4 chronic cervicitis tissues showed positive. the h ... | 1989 | 2560458 |
| [topoisomerase i from human placenta. functional activity of products of expression of cloned cdna fragments]. | immunoscreening of the human placenta cdna-library in the expression vector lambda gt11 using non-isotope detection based on the avidin-biotin system allowed to identify a number of clones encoding human topoisomerase i. the fusion protein from an extract of escherichia coli cells infected with the recombinant phage lambda gt11 interacts with the monoclonal antibody raised against topoisomerase i from calf thymus; the dissociation constant being 5.7.10(-8) m. the restricted dna fragments coding ... | 1989 | 2561176 |
| the transposable element tn3 promotes general recombination at the neighboring regions. | transposon tn3 was inserted into a trna operon of the amber suppressor su+2 on a transducing phage (lambda hci857nin5psu+2) by selecting phages with ampicillin resistance and su- phenotypes. in a strain thus obtained, tn3 was inserted between the promoter and the first trna gene of the operon, which was determined by dna sequencing. the su+2 trna operon on the transducing phage consisted of two trna genes for trna(met) and su+2 trna(2gln), which was a deletion derivative of the supb-e trna opero ... | 1989 | 2561260 |
| [escherichia coli phage receptors. minor porins and proteins participating in the specific transport as phage receptors]. | except for the main porin proteins ompc and ompf there exist the membrane proteins participating in the transport of specific substrates: phosphates, nucleosides, iron, vitamin b12, maltose and maltodextrins, that also play the role of phage receptors. some phages use as receptors the porins determined by the genes of lambdoid prophages. lamb protein that serves receptor for phage lambda exposes the amino acids sequence on the outer surface of membranes that participates in phage adsorption. the ... | 1989 | 2561376 |
| structure of the human gene for the proliferating cell nuclear antigen. | the proliferating cell nuclear antigen (pcna, cyclin) was originally defined as a nuclear protein whose appearance correlated with the proliferative state of the cell. it is now known to be a co-factor of dna polymerase delta and to be necessary for dna synthesis and cell cycle progression. cdna clones of human pcna have been isolated and, using one of these cdna, we have now obtained from a lambda phage library a clone containing the entire human pcna gene and flanking sequences. the human pcna ... | 1989 | 2565339 |
| mapping of the gene encoding the multifunctional protein carrying out the first three steps of pyrimidine biosynthesis to human chromosome 2. | the cad gene encodes a trifunctional protein that carries the activities of the first three enzymes (carbamyl phosphate synthetase ii, aspartate transcarbamylase, and dihydroorotase) of de novo pyrimidine biosynthesis. genomic fragments of the human cad gene have been obtained by screening a human genomic library in bacteriophage lambda using a syrian hamster cdna clone as a probe. these human genomic clones have been used to assign the cad gene to human chromosome 2 using in situ hybridization ... | 1989 | 2565865 |
| a plasmid to visualize and assay termination and antitermination of transcription in escherichia coli. | to facilitate the analysis of termination and antitermination of transcription in prokaryotes, a complex operon has been assembled into the pbr322 replicon, drawing upon natural and synthetic dna elements. this operon is initiated from a strongly inducible promoter without temperature restraints. it includes a severe transcription terminator and therefore requires antitermination of transcription to express a downstream lacz reporter gene. antitermination can be provided by an upstream n-utiliza ... | 1989 | 2567018 |
| the oct-1 homoeodomain directs formation of a multiprotein-dna complex with the hsv transactivator vp16. | the herpes simplex virus transactivator vp16 participates in the formation of a multiprotein-dna complex with the ubiquitous octamer-motif-binding factor oct-1. complex formation is dependent on specific amino acids in the oct-1 homoeodomain which are in positions analogous to positive control mutations in helix 2 of the lambda phage repressor helix-turn-helix motif, indicating that this structure is an ancient target for protein-protein interactions mediating transcriptional control. | 1989 | 2571937 |
| typing of listeria monocytogenes for epidemiological studies using dna probes. | we have investigated the possibility of using restriction fragment length polymorphisms (rflps) to distinguish different strains of listeria monocytogenes. cloned dna fragments (probes) were selected from a bacteriophage lambda gene library of l. monocytogenes (l1428). dnas from two lambda clones consisting of a total of approximately 20kb of probe dna were labelled with biotinylated dutp for use in these experiments. the criteria for probe selection were the ability both to hybridise with all s ... | 1989 | 2576579 |
| expression of protective and cardiac tissue cross-reactive epitopes of type 5 streptococcal m protein in escherichia coli. | the immunochemical properties of type 5 m protein antigens that were expressed in escherichia coli k-12 by recombinant lambda bacteriophages isolated from a gene bank of serotype 5 streptococcus pyogenes have been analyzed in detail. m proteins from partially purified bacteriophage lysates displayed precipitin lines of identity with a purified peptic extract of type 5 m protein (pep m5) in immunodiffusion assays. immunoblot analyses of the m protein-positive lysates demonstrated that the cloned ... | 1985 | 2579908 |
| transfer of human and murine globin-gene sequences into transgenic mice. | we have studied the transfer of human and murine globin gene sequences into fertilized mouse oocytes by microinjection. germline transmission was demonstrated for the human delta- and beta-globin genes contained in the bacteriophage lambda h beta g1. expression of these human globin-gene sequences was not detectable in either erythroid or nonerythroid tissues. a recombinant plasmid containing the murine beta maj promoter region coupled to the prokaryotic coding sequence for galactokinase was als ... | 1985 | 2580434 |
| the human alpha-fetoprotein gene. sequence organization and the 5' flanking region. | the human alpha-fetoprotein (afp) gene was isolated into three overlapping clones in bacteriophage lambda vectors and its sequence organization analyzed by restriction endonuclease mapping and nucleotide sequencing. the human afp gene is about 20 kilobase pairs long and contains 15 exons and 14 introns. the overall organization of the human afp gene is similar to that of the mouse afp gene, with all but two exons showing identical sizes. nucleotide sequences at all exon/intron junctions display ... | 1985 | 2580830 |
| mrna usage during drosophila melanogaster embryonic development. analysis of nine cloned dna segments. | a set of nine phage lambda clones containing inserts from drosophila melanogaster which are complementary to cdna made from oocyte poly(a)+ rna were selected from a larger group. these cloned elements code for a range of middle abundant rna sequences which show no appreciable change in abundance during drosophila embryogenesis. seven of the nine clones are complementary to two oocyte rnas, one to three rnas and one to four rnas. this study describes the changes that occur in these rnas during em ... | 1985 | 2581797 |
| automated dna sequencing methods involving polymerase chain reaction. | polymerase chain reaction (pcr) as a method for preparing dna templates has been used for several dna sequencing applications. an in situ procedure for directly sequencing pcr products by the dideoxy-termination method has been developed by using fluorophore-labeled sequencing primers. completed sequence reactions were combined and loaded into a single electrophoretic lane of a fluorescence-based dna sequence analyzer. dna targets devoid of a universal primer sequence could be sequenced with lab ... | 1989 | 2582616 |
| replication origin of a single-stranded dna plasmid pc194. | the replication of the single-stranded (ss) dna plasmid pc194 by the rolling circle mechanism was investigated using chimeric plasmids that possess two pc194 replication origins. one of the origins was intact, whereas the other was either intact or mutated. the origins were activated by inducing synthesis of the pc194 replication protein, under the control of lambda phage pl promoter. initiation of pc194 replication at one origin and termination at the other generated circular ssdna molecules sm ... | 1989 | 2583127 |
| the nucleotide sequence of a microvitellogenin encoding gene from the tobacco hornworm, manduca sexta. | a microvitellogenin (mvg)-coding gene (mvg) has been isolated from a lambda phage library prepared from the tobacco hornworm, manduca sexta. one of the lambda clones had a 15-kb insert and contained the entire mvg gene. a dna fragment (3.0 kb) containing this mvg gene has been sequenced. southern blot analysis showed that there may be more than one mvg gene in m. sexta. the putative transcriptional start point (tsp) for the cloned mvg was determined by primer extension analysis. this gene contai ... | 1989 | 2583514 |
| structure of the gene for human von willebrand factor. | von willebrand factor is a large multimeric plasma protein composed of identical subunits which contain four types of repeated domains. von willebrand factor is essential for normal hemostasis, and deficiency of von willebrand factor is the most common inherited bleeding disorder of man. four human genomic dna cosmid libraries and one bacteriophage lambda library were screened with von willebrand factor cdna probes. twenty positive overlapping clones were characterized that span the entire von w ... | 1989 | 2584182 |
| expression of the human parvovirus b19 protein fused to protein a in escherichia coli: recognition by igm and igg antibodies in human sera. | a 1.4 kb fragment (nucleotides 2430 to 3901) encoding portions of the human parvovirus b19 structural proteins was inserted into the prit2 plasmid expression vector containing the gene encoding staphylococcal protein a under the control of the phage lambda promoter pr. the fusion protein was used to raise antibodies in rabbits. the sera were shown by immune electron microscopy to agglutinate b19 particles and were also shown to recognize the vp2 b19 capsid protein, by western blot analysis. the ... | 1989 | 2584954 |
| cloning and analysis of a human 86-kda heat-shock-protein-encoding gene. | an 86-kda heat-shock-protein-encoding (hsp86) cdna probe permitted to identify, in whole genomic human dna, two ecori fragments of 2.6 and 5.3 kb. these two fragments, as well as an homologous phage lambda viii1 harboring about 19 kb of human dna, were isolated from genomic libraries. sequence analysis revealed that three different genomic hsp86 sequences had been cloned, one of them being the 5' half of a functional gene. this gene contains several introns, as compared to the entire hsp86-encod ... | 1989 | 2591742 |
| cloning of the crystalline cell wall protein gene of bacillus licheniformis nm 105. | a protein with a tetragonal pattern, defined as rs protein, was found on the wall surface of an alkaline phosphatase secretion-deficient mutant (nm 105) of bacillus licheniformis 749/c. the protein was present on the wall surface of the exponential-growth-phase cells, but at the stationary growth phase it was overproduced and hypersecreted. this protein was precipitated to homogeneity from the culture fluid by 80% ammonium sulfate saturation and chilled acetone. the molecular mass of the protein ... | 1989 | 2592345 |
| alteration of mitogenic responses of mononuclear cells by anti-ds dna antibodies resembling immune disorders in patients with systemic lupus erythematosus. | anti-double-stranded dna antibodies (anti-dna) purified from pooled active sle sera by lambda phage dna-affinity chromatography was found to affect phytohemagglutinin (pha) and pokeweek mitogen (pwm)-induced responses of normal mononuclear cells. anti-dna at a concentration of 0.25 mg/ml (equivalent to 21 units/ml of dna binding activity) significantly suppressed the pha-induced [3h]thymidine incorporation of mononuclear cells in 3 days of culture but had no effect on 5-day and 7-day cultures. i ... | 1989 | 2595347 |
| [restriction-modification systems of type ii in shigella strains]. | two restriction-modification systems specified by two plasmids are discovered in the clinical species of shigella. the plasmids are designated pkmr114 and pkmr115. both are of 60.800 bp and belong to the incn incompatibility group. the ecori, ecorv, hindiii restriction patterns of both plasmid dnas are identical. as shown by efficiency of plating of bacteriophage lambda vir on the strains harbouring plasmids encoding ecori, ecorii, ecoriii, ecoriv, ecorv systems and plasmids studied, the discove ... | 1989 | 2599373 |
| muc18, a marker of tumor progression in human melanoma, shows sequence similarity to the neural cell adhesion molecules of the immunoglobulin superfamily. | the muc18 antigen is an integral membrane glycoprotein of 113 kda whose expression on primary human melanomas correlates with poor prognosis and the development of metastatic disease. muc18 is expressed only sporadically in benign melanocytic nevi and thin primary melanomas that have a low probability of metastasizing. however, with increasing tumor thickness, muc18 expression becomes more frequent and it is found on 80% of advanced primary tumors and metastases. muc18-encoding cdna clones were ... | 1989 | 2602381 |
| cloning of the bovine major histocompatibility complex class ii genes. | class ii genes of the bovine major histocompatibility complex (mhc) have been cloned from a genomic library. the library was constructed in the bacteriophage lambda vector embl3 and comprises approximately 10 times the equivalent of the haploid genome. half the library was screened with the human dqa, dqb, dra and drb cdna probes. of the 100 positively hybridizing phage clones, 37 were eventually fully characterized and mapped by means of southern blot analysis. the exons encoding the first, sec ... | 1989 | 2610402 |
| the missing nucleoside experiment: a new technique to study recognition of dna by protein. | we report a new technique for quickly determining which nucleosides in a dna molecule are contacted by a sequence-specific dna-binding protein. our method is related to the recently reported "missing contact" experiment [brunelle, a., & schleif, r. f. (1987) proc. natl. acad. sci. u.s.a. 84, 6673-6679]. we treat the dna molecule with the hydroxyl radical to randomly remove nucleosides. the ability of protein to bind to gapped dna is assayed by gel mobility shift. nucleosides important to protein ... | 1989 | 2611245 |