Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| genomic organization of the human nsp gene, prototype of a novel gene family encoding reticulons. | recently, cdna cloning and expression of three mrna variants of the human nsp gene were described. this neuroendocrine-specific gene encodes three nsp protein isoforms with unique amino-terminal parts, but common carboxy-terminal parts. the proteins, with yet unknown function, are associated with the endoplasmic reticulum and therefore are named nsp reticulons. potentially, these proteins are neuroendocrine markers of a novel category in human lung cancer diagnosis. here, the genomic organizatio ... | 1996 | 8833145 |
| conjugative transposon tn916: evidence for excision with formation of 5'-protruding termini. | conjugative transposons are genetic elements able to promote their own intracellular transposition and intercellular conjugal transfer. they move by an excision-integration system related to that of lambdoid phages, in which the first step is the excision of the transposon from the donor replicon to form a covalently closed circular intermediate which contains a heteroduplex joint. in this work, sequencing both strands of the circular intermediate heteroduplex joint, it was found that, as during ... | 1996 | 8824634 |
| structural organization of the human gene (pkr) encoding an interferon-inducible rna-dependent protein kinase (pkr) and differences from its mouse homolog. | the gene encoding the interferon-inducible, rna-dependent protein kinase (pkr) was isolated as lambda phage and p1 phage clones from human genomic dna libraries and characterized by southern blot and nucleotide sequence analyses. southern blot analyses were consistent with a single pkr gene, and genomic clones colocalized by fluorescence in situ hybridization to human chromosome 2p. sequence analysis demonstrated that the human pkr gene consists of 17 exons and spans about 50 kb. the aug transla ... | 1996 | 8812437 |
| surface display of proteins on bacteriophage lambda heads. | we have developed plasmid and phage vectors for the display of foreign proteins on the surface of bacteriophage lambda capsid by modifying the d gene which encodes the major head protein gpd. the vectors have multiple cloning sites, and permit colour selection and conditional chain termination for recombinants. displayed proteins can be fused to either the n or c terminus of gpd by a peptide linker. the conditional chain termination scheme, via a host escherichia coli suppressor activity, allows ... | 1996 | 8809176 |
| genetic analysis of the bacteriophage lambda attl nucleoprotein complex. | site-specific recombination in bacteriophage lambda involves interactions among proteins required for integration and excision of dna molecules. we have analyzed the elements required to form an in vivo nucleoprotein complex of integrase (int) and integration host factor (ihf). interaction of int with the core (the site of strand exchange) is stabilized by the flanking arm region of attl. ihf, in addition to int, is required for efficient int-core binding. we used the in vivo attl binding assay ... | 1996 | 8807282 |
| homology requirements for double-strand break-mediated recombination in a phage lambda-td intron model system. | many group i introns encode endonucleases that promote intron homing by initiating a double-strand break-mediated homologous recombination event. a td intron-phage lambda model system was developed to analyze exon homology effects on intron homing and determine the role of the lambda 5'-3' exonuclease complex (red alpha beta) in the repair event. efficient intron homing depended on exon lengths in the 35- to 50-bp range, although homing levels remained significantly elevated above nonbreak-media ... | 1996 | 8807281 |
| analysis of genetic instability during mammary tumor progression using a novel selection-based assay for in vivo mutations in a bacteriophage lambda transgene target. | genetic instability is thought to be responsible for the numerous genotypic changes that occur during neoplastic transformation and metastatic progression. to explore the role of genetic instability at the level of point mutations during mammary tumor development and malignant progression, we combined transgenic mouse models of mutagenesis detection and oncogenesis. bitransgenic mice were generated that carried both a bacteriophage lambda transgene to assay mutagenesis and a polyomavirus middle ... | 1996 | 8799156 |
| interactions between a minimal protein serine/threonine phosphatase and its phosphopeptide substrate sequence. | the protein phosphatase encoded by coliphage lambda (pplambda) was found to be the equivalent of the minimal catalytic core of serine/threonine protein phosphatases (pp) by biochemical and mutational criteria. bacterially expressed truncated versions of pp1 and pp5 phosphatases, representing the catalytic cores homologous to pplambda, exhibited potent phosphatase activity. unlike full-length pp1, but like pplambda, the recombinant cores could use casein, p-nitrophenyl phosphate, and a wide varie ... | 1996 | 8798696 |
| mutations affecting the high affinity atpase center of gpa, the large subunit of bacteriophage lambda terminase, inactivate the endonuclease activity of terminase. | phage lambda terminase carries out the cos cleavage reaction that generates mature chromosomes from immature concatemeric dna. the atp-stimulated endonuclease activity of terminase is located in gpa, the large terminase subunit. there is a high affinity atpase center in gpa, and a match to the conserved p-loop of known atpases is found starting near residue 490. changing the conserved p-loop lysine at residue 497 of gpa affects the high affinity atpase activity of terminase. in the present work, ... | 1996 | 8794874 |
| isolation and subcloning of chitinase clone from chickpea genomic library. | chickpea genomic library constructed earlier in phage lambda (embl-3) was screened for the presence of chitinase clone using tobacco chitinase cdna as a probe. positive clones obtained by primary screening of plaques (2 x 10(6)) were ascertained by secondary and tertiary screening. presence of chitinase insert in the positive clones obtained, was further confirmed by restricting phage dna with sal i and then doing southern with tobacco chitinase. the insert band was eluted out and subcloned in p ... | 1996 | 8792650 |
| thi1, a thiamine biosynthetic gene in arabidopsis thaliana, complements bacterial defects in dna repair. | an arabidopsis thaliana cdna was isolated by complementation of the escherichia coli mutant strain bw535 (xth, nfo, nth), which is defective in dna base excision repair pathways. this cdna partially complements the methyl methane sulfonate (mms) sensitive phenotype of bw535. it also partially corrects the uv-sensitive phenotype of e. coli ab1886 (uvra) and restores its ability to reactivate uv-irradiated lambda phage. it has an insert of ca. 1.3 kb with an open reading frame of 1047 bp (predicti ... | 1996 | 8790291 |
| sequencing of a 23 kb fragment from saccharomyces cerevisiae chromosome vi. | plasmid clone gapb and lambda phage clone 4682, which contain fragments of saccharomyces cerevisiae chromosome vi, were analysed. a 23 kb sequence was determined and ten open reading frames (orfs) were revealed. among them, five orfs were identical to five yeast genes (sec4, msh4, spb4, deg1 and nic96), two were identical to transposable elements (tya and tyb), one (gapborff003) was highly homologous to a yeast expressed sequence tag, and another (4682orff002) was predicted to be a nuclear prote ... | 1996 | 8789262 |
| structural prediction of a- and b-dna duplexes based on coordinates of the phosphorus atoms. | the sequence-dependent structure of dna double helices was studied extensively during the past 10 years. how the backbone structure correlates with the base structure in a duplex conformation is still an important yet open question. using a set of reduced coordinates and a least-squares fitting procedure, we have developed a method to predict structures for b-dna duplexes based on coordinates of the phosphorus atoms. this method can be used to predict all-atom structures for both bent and straig ... | 1996 | 8789108 |
| characterization of a translocation-associated deletion defines the candidate region for the gene responsible for branchio-oto-renal syndrome. | fluorescence in situ hybridization analysis of an 8q translocation breakpoint, dir ins(8)(q24.11;q13.3;q21.13), carried by an individual presenting with branchio-oto-renal (bor) syndrome, resulted in the identification of an associated deletion. the generation of a yac contig and the isolation of overlapping recombinant p1 and lambda phage clones from the region allowed further characterization of this deletion. its size was estimated to be between 470 and 650 kb, and it was flanked by the two p ... | 1996 | 8786145 |
| structure of the human laminin gamma 2 chain gene (lamc2): alternative splicing with different tissue distribution of two transcripts. | we have determined the structure of the human laminin gamma 2 chain gene (lamc2), which is mutated in some patients with junctional epidermolysis bullosa. eight lambda phage clones isolated from a genomic library and three subgenomic lambda phage clones made from a plasmid artificial chromosome clone spanned 75 kb, including the 55-kb gene. the lamc2 gene contains 23 exons and is structurally highly homologous with the 28-exon lamc1 gene (kallunki et al., 1991, j. biol. chem. 266: 221-228), with ... | 1996 | 8786121 |
| conserved structure and adjacent location of the thrombin receptor and protease-activated receptor 2 genes define a protease-activated receptor gene cluster. | thrombin is a serine protease that elicits a variety of cellular responses. molecular cloning of a thrombin receptor revealed a g protein-coupled receptor that is activated by a novel proteolytic mechanism. recently, a second protease-activated receptor was discovered and dubbed par2. par2 is highly related to the thrombin receptor by sequence and, like the thrombin receptor, is activated by cleavage of its amino terminal exodomain. also like the thrombin receptor, par2 can be activated by the h ... | 1996 | 8784787 |
| membrane topology of the mannose transporter of escherichia coli k12. | the mannose transporter of the bacterial phosphotransferase system mediates carbohydrate transport across the cytoplasmic membrane concomitant with carbohydrate phosphorylation. it also functions as a receptor for bacterial chemotaxis [adler.j. & epstein, w. (1974) proc. natl acad. sci. usa 71. 2895-2899] and is required for infection of the cell by bacteriophage lambda where it most likely functions as a pore for penetration of phage dna [elliott, j. & arber, w. (1978) mol. & gen. genet. 161, 1 ... | 1996 | 8774730 |
| device for the simultaneous screening of bacteriophage lambda clones. | 1996 | 8770396 | |
| [organization of the gene for the beta-subunit of human photoreceptor cyclic gmp phosphodiesterase]. | two recombinant bacteriophage lambda clones encoding a 27.8-kb fragment of the human phosphodiesterase beta-subunit gene were isolated from a human genomic library. the nucleotide sequences of 19 exons (from the 4th to 22nd), 18 introns, and the 3'-flanking region were determined. the analysis of the nucleotide sequence of the phosphodiesterase beta-subunit gene revealed four alu repeats and four minisatellite regions. | 1996 | 8768262 |
| a proposal for using modified site-specific recombination systems for making insertions into a chosen chromosomal site in vivo based on the analysis of lambda phage integration. | a proposal is presented here to use modified mobile genetic elements for making chromosomal insertions in vivo, into any desired chromosomal site. the idea lies in replacing the sequences which direct specificity of integration of those elements with other dna sequences, homologous to the desired target chromosomal site. the idea is analysed on the basis of a lambda phage integration system. a design for a universal system for making chromosomal insertions into any site of choice is proposed. | 1996 | 8763358 |
| characterization of the rat glutathione s-transferase yc2 subunit gene, gsta5: identification of a putative antioxidant-responsive element in the 5'-flanking region of rat gsta5 that may mediate chemoprotection against aflatoxin b1. | we have isolated and characterized genomic dna encoding the rat glutathione s-transferase yc2 subunit. this protein is now referred to as rgsta5 and is noteworthy because of its high activity towards aflatoxin b1-8,9-epoxide, its marked inducibility by chemoprotectors, its sex-specific regulation, and its over-expression in hepatoma and preneoplastic nodules. the rgsta5 gene, which was isolated on two overlapping bacteriophage lambda clones, is approx. 12 kb in length and, unlike other class alp ... | 1996 | 8761455 |
| cloning, restriction endonuclease mapping and partial sequence analysis of the genome of human herpesvirus 7 strain ji. | human herpesvirus 7 (hhv-7) is a recently isolated herpesvirus that has been shown to be related to human cytomegalovirus and human herpesvirus 6 and to be a member of the betaherpesvirus subgroup. here we report the cloning, restriction endonuclease mapping and partial sequence analysis of hhv-7 strain ji dna. virus particles were obtained from the supernatant of infected supt1 cells, the dna isolated by proteinase k treatment-phenol extraction, and full-length viral dna was purified and isolat ... | 1996 | 8760442 |
| identification of an up element within the ihf binding site at the pl1-pl2 tandem promoter of bacteriophage lambda. | an up element defines a supplementary promoter element located upstream of the -35 region that stimulates transcription by interacting with the c-terminal domain of the rna polymerase alpha subunit (alpha ctd). the alpha ctd also responds to various transcription activators, including the integration host factor protein, ihf, in the stimulation of the bacteriophage lambda pl promoter. pl consists of the tandem pl1-pl2 promoters where pl1 is stimulated and pl2 is repressed by ihf. we identified a ... | 1996 | 8759315 |
| function of e. coli rna polymerase sigma factor sigma 70 in promoter-proximal pausing. | the sigma factor sigma 70 of e. coli rna polymerase acts not only in initiation, but also at an early stage of elongation to induce a transcription pause, and simultaneously to allow the phage lambda gene q transcription antiterminator to act. we identify the signal in dna that induces early pausing to be a version of the sigma 70 -10 promoter consensus, and we show that sigma 70 is both necessary for pausing and present in the paused transcription complex. regions 2 and 3 of sigma 70 suffice to ... | 1996 | 8756730 |
| raman spectroscopy of the ff gene v protein and complexes with poly(da): nonspecific dna recognition and binding. | raman spectra of crystals and solutions of the single-stranded dna binding protein of bacteriophage ff (gene v protein, gvp) and of solution complexes of gvp with single-stranded poly-(deoxyadenylic acid) [poly(da)] reveal the following: (i) the gvp secondary and tertiary structures are similar in solution and in the crystal and are dominated by beta-sheet domains, in agreement with nmr and x-ray findings. (ii) subunit conformation and side chain environments of gvp are virtually unchanged over ... | 1996 | 8755742 |
| complete structure of the human alpha-albumin gene, a new member of the serum albumin multigene family. | the nucleotide sequence of the human alpha-albumin gene, including 887 bp of the 5'-flanking region and 1311 bp of the 3-flanking region (24,454 in total), was determined from three overlapping lambda phage clones. the sequence spans 22,256 bp from the cap site to the polyadenylylation site, revealing a gene structure of 15 exons separated by 14 introns. the methionine initiation codon atg is within exon 1; the termination codon tga is within exon 14. exon 15 is entirely untranslated and contain ... | 1996 | 8755513 |
| cloning and analysis of igg kappa and igg lambda anti-thyroglobulin autoantibodies from a patient with hashimoto's thyroiditis: evidence for in vivo antigen-driven repertoire selection. | antibodies to thyroglobulin (tg) are commonly found in patients with the autoimmune thyroid diseases graves' disease and hashimoto's thyroiditis as well as in individuals with apparently normal thyroid function. although it is not clear how tg abs are involved in the pathology of the diseases, the study and analysis of these abs may nevertheless be instructive in allowing the development of an ab response to an autoimmune disease-associated self ag to be followed. we have prepared igg kappa and ... | 1996 | 8752947 |
| construction and characterization of a potential live oral carrier-based vaccine against vibrio cholerae o139. | the rfb region from vibrio cholerae o139 strain mo45 was cloned from cosmid gene banks established in escherichia coli hb101, using an immunoblot assay for screening of the correct clones. immunoblot analysis of lipopolysaccharide (lps) preparations revealed the presence of two types of positive clones: (i) those expressing only a short core-linked o polysaccharide (sops) and (ii) those also expressing a highly polymerized capsular polysaccharide (cps) not bound to the e. coli k-12 lps core. in ... | 1996 | 8751900 |
| sequencing of an 18.8 kb fragment from saccharomyces cerevisiae chromosome vi. | the nucleotide sequence of lambda phage clone 4121, which contains the 18.8 kb fragment of saccharomyces cerevisiae chromosome vi left arm, was determined. this sequence had seven open reading frames (orfs), four of which were identical to known genes (act1, ypt1, tub2 and rpo41). another three orfs (4121orfr003, 4121orfr004 and 4121orfrn001) were highly homologous to fet3 multi-copper oxidase, glucose transport protein, and hypothetical protein of yil106w on chromosome ix, respectively. 4121orf ... | 1995 | 8750241 |
| overproduction and one-step purification of escherichia coli udp-n-acetylglucosamine enolpyruvyl reductase. | the escherichia coli gene murb, encoding the enzyme uridine-5'-diphospho-n-acetyl-2-amino-2-deoxy-3-o-lactylglucosenicoti namide adenine dinucleotide phosphate oxidoreductase (ec 1.1.1.158) (ep-reductase), the second enzyme in the peptidoglycan biosynthetic pathway, has been amplified using pcr technology with the kohara recombinant lambda phage e11c11 (534) as template. the synthetic gene was subcloned into the ndei and bamhi restriction sites of the expression vector pt7-7, designed to utilize ... | 1995 | 8746627 |
| the reactivity of sera from patients with systemic lupus erythematosus to seven different species of single and double stranded deoxyribonucleic acids. | anti-dna antibodies are frequently found in the serum of patients with systemic lupus erythematosus (sle). to understand whether the avidity of sle sera to different species of single-stranded (ss) and double-stranded (ds) dna is different or not, the reactivity of active sle sera to seven species of dna from viral, bacterial, piscine, and mammalian sources was compared. | 1996 | 8737719 |
| [expression of hiv-1 epitopes included in particles formed by human hepatitis b virus nucleocapsid protein]. | hybrids of the core protein of hepatitis b virus (hbcag) have been designed which carry n-terminal insertions of b- and t-cell epitopes of hiv-1 an immunodominant b-epitope from gp41, a t-cell epitope from p34 pol, and a cluster of b- and t-cell epitopes from p17 gag. the hybrids have been synthesized using two expression systems-one based on the thermoinducible pr promoter of bacteriophage lambda and the other one based on phi 10 promoter of bacteriophage t7 with 3-5% and 7-14% yields, respecti ... | 1996 | 8724609 |
| structural distortions induced by integration host factor (ihf) at the h' site of phage lambda probed by (+)-cc-1065, pluramycin, and kmno4 and by dna cyclization studies. | integration host factor (ihf) is a sequence-specific dna-bending protein that is proposed to interact with dna primarily through the minor groove. we have used various chemical probes [(+)-cc-1065, a minor-groove-specific agent that alkylates n3 of adenine and traps bends into the minor groove; pluramycin, a minor-major-groove threading intercalator that alkylates n7 of guanine; kmno4, which reacts more strongly with bases in denatured dna] to gain more information on the interaction of ihf with ... | 1996 | 8718873 |
| structure and organization of the bovine oxytocin receptor gene. | a dna probe specific for the v and vi transmembrane domains of the bovine oxytocin receptor was initially prepared by reverse transcription pcr, and its structure and specificity confirmed by dna sequencing. this probe was then used to screen a bovine genomic dna library in bacteriophage lambda, and three positive clones were purified, subjected to restriction analysis and relevant fragments sequenced. parallel to this, a cdna library prepared using bovine endometrial rna at the time of ovulatio ... | 1995 | 8713979 |
| telomere-homologous sequences occur near the centromeres of many tomato chromosomes. | several bacteriophage lambda clones containing interstitial telomere repeats (itr) were isolated from a library of tomato genomic dna by plaque hybridization with the cloned arabidopsis thaliana telomere repeat. restriction fragments lacking highly repetitive dna were identified and used as probes to map 14 of the 20 lambda clones. all of these markers mapped near the centromere on eight of the twelve tomato chromosomes. the exact centromere location of chromosomes 7 and 9 has recently been dete ... | 1996 | 8709958 |
| transcription antitermination: the lambda paradigm updated. | coliphage lambda employs systems of transcription termination and antitermination to regulate gene expression. early gene expression is regulated by the phage-encoded n protein working with a series of escherichia coli proteins, nus, at rna sites, nut, to modify rna polymerase to a termination-resistant form. expression of lambda late genes is regulated by the phage-encoded q antitermination protein. q, which appears to use only one host factor, acts at a dna site, qut, to modify rna polymerase ... | 1995 | 8709839 |
| rho-dependent termination of transcription is governed primarily by the upstream rho utilization (rut) sequences of a terminator. | a rho-dependent transcription terminator in escherichia coli dna consists of an upstream part for rho utilization (rut) and the transcription stop point (tsp) region. to test the role of the tsp region variants of the coliphage lambda cro gene terminator, tr1, containing inserts of non-terminator sequences between its rut and tsp regions were tested for termination function. the results showed that termination occurred with high efficiency at multiple sites in each of the new sequences with the ... | 1996 | 8702947 |
| effect of eugenol on the mutagenicity of benzo[a]pyrene and the formation of benzo[a]pyrene-dna adducts in the lambda-lacz-transgenic mouse. | to study the possible reduction by eugenol of the mutagenicity and genotoxicity of benzo[a]pyrene (b[a]p) in vivo, the lambda-lacz-transgenic mouse strain 40.6 (muta mouse) was used. male mice were fed a diet containing 0.4% (w/w) eugenol or a control diet for 58 days. on day 10, half of the mice received an i.p. dose of 100 mg/kg b.w. b[a]p. the lacz mutants were recovered by packaging of dna isolated from liver into lambda phage, and expressed in e. coli c lacz-reca-gale- bacteria. in both con ... | 1996 | 8700188 |
| detection of dna damage induced by human carcinogens in acellular assays: potential application for determining genotoxic mechanisms. | positive outcomes of in vitro genotoxicity tests may not always occur as a consequence of direct reaction of a compound or a metabolite with dna. to follow-up positive responses in in vitro tests, we developed two supplemental, cell-free assays to examine the potential of compounds and metabolites to directly damage dna. calf thymus dna was used as the target for the direct detection of adducts by 32p-postlabeling/tlc and electrochemical detection, and alkaline gel electrophoresis was used to de ... | 1996 | 8692229 |
| systematic mapping of autonomously replicating sequences on chromosome v of saccharomyces cerevisiae using a novel strategy. | we have developed a new procedure for easy and rapid identification of autonomously replicating sequences (arss) and have applied it to the analysis of chromosome v of saccharomyces cerevisiae. the procedure makes use of the ordered lambda phage clone bank of this chromosome that we have constructed, and includes transposition of a mini-transposon and selection of transposon-containing derivatives, isolation of their dna and circularization at their cos-ends, transformation of yeast cells with t ... | 1996 | 8686374 |
| interaction between camp-dependent protein kinase catalytic subunit and peptide inhibitors analyzed with lambda repressor fusions. | the lambda phage repressor is currently used as a genetic tool to analyze homodimeric interactions in escherichia coli. we have applied this system to detect the interaction that takes place within an enzyme-protein inhibitor complex. the sequences encoding the catalytic subunit of the camp-dependent protein kinase and the active portion of the natural thermostable protein kinase inhibitor have been fused to the carboxy terminus of the repressor dna binding domain and introduced into compatible ... | 1996 | 8683565 |
| specificity mechanisms in the control of transcription. | in this overview we analyze and illustrate the principles underlying some of the specificity mechanisms that control the initiation, elongation, and termination phases of transcription. thermodynamic mechanisms dominate in the first steps of initiation, where promoters at various levels of activation can be considered to be in competition for a limiting supply of core rna polymerase. in the later stages of initiation, as well as in elongation and termination, the regulatory mechanisms that contr ... | 1996 | 8672714 |
| evaluation of a plasmid-based transgenic mouse model for detecting in vivo mutations. | to study in vivo somatic mutations a c57bl/6 transgenic mouse model was constructed harboring multiple chromosomally integrated copies of the plasmid pur288, which carried the lacz reporter gene as the mutational target. we previously demonstrated that lacz-containing plasmids could be rescued from their integrated state efficient enough to detect mutations in lacz by positive selection. the smaller size of the plasmid vector, as compared with our earlier transgenic mouse model based on bacterio ... | 1996 | 8671725 |
| frequent spontaneous deletions at a shuttle vector locus in transgenic mice. | transgenic mice carrying multiple copies of a recoverable lambda phage shuttle vector (lambda supf) were constructed for the purpose of studying mutagenesis in a whole animal. spontaneous mutations in rescued supf target genes from several different lines of transgenic mice were analyzed. one mouse line, 1139, was identified in which the frequency of spontaneous mutations was unusually high (3.15 x 10(-4)), 20-fold higher than in other transgenic mice carrying a similar number of copies of the l ... | 1996 | 8671715 |
| synthesis of the bacteriophage lambda p protein in amino acid-starved escherichia coli cells. | it was demonstrated previously that in isoleucine-starved escherichia coli rela mutants harboring a plasmid derived from bacteriophage lambda the lambda o protein is not synthesized. however, a protein which coprecipited with the lambda o during immunoprecipitation with anti-lambda o serum was synthesized during the relaxed response. here we found that this protein is the lambda p gene product. despite significant inhibition of transcription from the pr promoter (which produces mrna for the lamb ... | 1996 | 8670253 |
| a multicopy suppressor of nin1-1 of the yeast saccharomyces cerevisiae is a counterpart of the drosophila melanogaster diphenol oxidase a2 gene, dox-a2. | nin1 is an essential gene for growth of the yeast saccharomyces cerevisiae and was recently found to encode a component of the regulatory subunit of the 26s proteasome. the nin1-1 mutant is temperature sensitive and its main defect is in g1/s progression and g2/m progression at non-permissive temperatures. one of the two multicopy suppressors of nin1-1, sun2 (suppressor of nin1-1), was found to encode a protein of 523 amino acids whose sequence is similar to those of drosophila melanogaster diph ... | 1996 | 8668124 |
| the rna chain elongation rate of the lambda late mrna is unaffected by high levels of ppgpp in the absence of amino acid starvation. | in this study, the effects of high levels of guanosine tetraphosphate (ppgpp) on the decay and rna chain elongation kinetics of the bacteriophage lambda late transcript in escherichia coli were examined in the absence of amino acid starvation. the accumulation, mrna decay kinetics, and rna chain elongation rate of the lambda late mrna were determined after heat induction of lambdaci857 lysogens in the presence of high levels of ppgpp induced from a relaalpha fragment-overproducing plasmid. the a ... | 1996 | 8663373 |
| structure-function analysis of the zinc finger region of the dnaj molecular chaperone. | dnaj is a molecular chaperone, which not only binds to its various protein substrates, but can also activate the dnak cochaperone to bind to its various protein substrates as well. dnaj is a modular protein, which contains a putative zinc finger motif of unknown function. quantitation of the released zn(ii) ions, upon challenge with p-hydroxymercuriphenylsulfonic acid, and by atomic absorption showed that two zn(ii) ions interact with each monomer of dnaj. following the release of zn(ii) ions, t ... | 1996 | 8662861 |
| cloning and sequencing analysis of three amylase cdnas in the shrimp penaeus vannamei (crustacea decapoda): evolutionary aspects. | in penaeus vannamei, alpha-amylase is the most important glucosidase and is present as at least two major isoenzymes which have been purified. in order to obtain information on their structure, a hepatopancreas cdna library constructed in phage lambda-zap ii (strategene) was screened using a synthetic oligonucleotide based on the amino acid sequence of a v8 staphylococcal protease peptide of p. vannamei alpha-amylase. three clones were selected: amy sk 37 (embl sequence accession number: x 77318 ... | 1996 | 8661999 |
| physical assignments of 68 porcine cosmid and lambda clones containing polymorphic microsatellites. | two lambda phage and 66 cosmids containing informative porcine microsatellites were assigned to 17 of 18 porcine autosomes and the x chromosome (chr) by fluorescence in situ hybridization (fish). these assignments provide additional physically anchored markers to integrate the porcine physical and genetic maps. | 1996 | 8661726 |
| structure of the human type iv collagen col4a6 gene, which is mutated in alport syndrome-associated leiomyomatosis. | basement membrane (type iv) collagen, a subfamily of the collagen protein family, is encoded by six distinct genes in mammals. three of those, col4a3, col4a4, and col4a5, are linked with alport syndrome (hereditary nephritis). patients with leimoyomatosis associated with alport syndrome have been shown to have deletions in the 5' end of the col4a6 gene, in addition to having deletions in col4a5 (zhou et al., science 261: 1167-1169, 1993). the human col4a6 gene is reported to be 425 kb as determi ... | 1996 | 8661006 |
| amphimeric mitochondrial genomes of petite mutants of yeast. i. flip-flop amphimers make up the mitochondrial genomes of "palindromic" petite mutants of yeast. | the mitochondrial (mt) genomes of three spontaneous cytoplasmic "palindromic" petite mutants of yeast were studied by restriction-enzyme analysis. these mt genomes were shown to be made up of an amplified "master basic unit" consisting of two inverted segments (a and a) and of two different unique segments (d and t) separating them. the basic unit was called "amphimeric", this term having been first proposed for certain lambda-phage mutants. we propose that in the mt genomes of the petite mutant ... | 1996 | 8660459 |
| tsp49i (acgt/), a thermostable neoschizomer of the type ii restriction endonuclease maeii (a/cgt), discovered in isolates of the genus thermus from the azores, iceland and new zealand. | one hundred and forty eight isolates of the genus thermus, from neutral and alkaline hot water springs on four continents, have been screened for the presence of restriction endonuclease activity. an isolate (sm49) from the island of sao miguel, in the azores, showed a high level of restriction endonuclease activity when a cell-free extract was incubated with lambda phage dna at 65 degrees c. a type ii restriction endonuclease (tsp49i) has been partially purified from this isolate and the recogn ... | 1996 | 8657557 |
| topology of the membrane protein lamb by epitope tagging and a comparison with the x-ray model. | we previously developed a genetic approach to study, with a single antibody, the topology of the outer membrane protein lamb, an escherichia coli porin with specificity towards maltodextrins and a receptor for bacteriophage lambda. our initial procedure consisted of inserting at random the same reporter epitope (the c3 neutralization epitope from poliovirus) into permissive sites of lamb (i.e., sites which tolerate insertions without deleterious effects on the protein activities or the cell). a ... | 1996 | 8655540 |
| epitope-specific tolerance induction with an engineered immunoglobulin. | isologous and heterologous immunoglobulins have been shown to be extremely effective as tolerogenic carriers for nearly 30 years. the efficacy of these proteins is due in part to their long half-life in vivo, as well as their ability to crosslink surface igm with fc receptors. the concept of using igg as a carrier molecule to induce unresponsiveness in the adult immune system has been exploited for simple haptens, such as nucleosides, as well as for peptides. to further evaluate the in vivo pote ... | 1996 | 8643522 |
| use of genomic dna probes for the diagnosis of acute sarcocystosis in experimentally infected cattle. | two clones of 1.4 and 4.33 kilobase pairs (kbp) dna inserts, were selected from a sarcocystis cruzi sporozoite genomic library constructed in bacteriophage lambda gt10. these clones strongly hybridized with sporozoite and merozoite dna and were evaluated as probes for detection of merozoite dna in clinical samples. of five calves in the experiment, four were each orally dosed with approximately 200,000 s. cruzi sporocysts; one calf served as non-infected control. subsequently, blood was collecte ... | 1996 | 8638397 |
| a refined vector system for the in vitro construction of single-copy transcriptional or translational fusions to lacz. | new single-copy vectors based on lambda phage have been developed for creating either transcriptional (operon) or translational (gene) fusions to the lacz gene. the improvements of these vectors over the previous lambda tl61 vector include: (i) incorporation of a tetracycline-resistance-encoding gene (tcr) to permit direct selection of lysogens, (ii) low-background beta-galactosidase activity, (iii) the ability to accept dna inserts up to 8 kb in size, and (iv) an expanded multiple cloning site ... | 1996 | 8635751 |
| identification of functional regions of the nun transcription termination protein of phage hk022 and the n antitermination protein of phage lambda using hybrid nun-n genes. | phages lambda and hk022 express proteins n and nun, respectively, each of which acts with a number of escherichia coli host nus factors at lambda nut rna sites, to influence transcription elongation. the lambda nut sites, nearly identical sequences located downstream of the early promoters, pl and pr, were first identified as cis-acting signals required for the action of n in forming termination-resistant transcription complexes. surprisingly, the nun protein, resembling n and expressed by anoth ... | 1996 | 8632463 |
| a family of genes coding for two serologically distinct chicken interferons. | southern blot analysis and screening of a genomic lambda phage library with the previously cloned chicken interferon (ifn) cdna indicated that the chicken genome contains at least 10 ifn genes. a particularly strongly hybridizing phage clone that we analyzed in more detail carried a head to tail arrangement of three intron-less ifn genes that differed from each other and from the cloned chicken ifn cdna by only a few base changes. the primary translation products of these three ifn genes consist ... | 1996 | 8631799 |
| overexpression of an mrna dependent on rare codons inhibits protein synthesis and cell growth. | lambda's int gene contains an unusually high frequency of the rare arginine codons aga and agg, as well as dual rare arg codons at three positions. related work has demonstrated that int protein expression depends on the rare aga trna. strong transcription of the int mrna with a highly efficient ribosome-binding site leads to inhibition of int protein synthesis, alteration of the overall pattern of cellular protein synthesis, and cell death. synthesis or stability of int and ampicillin resistanc ... | 1996 | 8631683 |
| escherichia coli thymidylate kinase: molecular cloning, nucleotide sequence, and genetic organization of the corresponding tmk locus. | thymidylate kinase (dtmp kinase; ec 2.7.4.9) catalyzes the phosphorylation of dtmp to form dtdp in both de novo and salvage pathways of dttp synthesis. the nucleotide sequence of the tmk gene encoding this essential escherichia coli enzyme is the last one among all the e. coli nucleoside and nucleotide kinase genes which has not yet been reported. by subcloning the 24.0-min region where the tmk gene has been previously mapped from the lambda phage 236 (e9g1) of the kohara e. coli genomic library ... | 1996 | 8631667 |
| precise limitation of concerted evolution to orfs in mosquito hsp82 genes. | two hsp82 genes were isolated from the malaria vector anopheles albimanus in a single lambda phage clone. the two genes are in a head-to-head arrangement separated by approx. 0.9 kbp. northern hybridizations and 5' race demonstrate that both genes are transcribed, have moderate levels of constitutive transcription, and are also heat-inducible with maximum transcript accumulation occurring after 40 degrees c heat shocks. both genes have typical heat-shock promoters and conserved intron boundaries ... | 1996 | 8630537 |
| a bipartite signaling mechanism involved in dnaj-mediated activation of the escherichia coli dnak protein. | the dnak and dnaj heat shock proteins function as the primary hsp70 and hsp40 homologues, respectively, of escherichia coli. intensive studies of various hsp70 and dnaj-like proteins over the past decade have led to the suggestion that interactions between specific pairs of these two types of proteins permit them to serve as molecular chaperones in a diverse array of protein metabolic events, including protein folding, protein trafficking, and assembly and disassembly of multisubunit protein com ... | 1996 | 8626673 |
| the rz1 gene product of bacteriophage lambda is a lipoprotein localized in the outer membrane of escherichia coli. | the rz1 gene of bacteriophage lambda is located within the rz1 lysis gene. it codes for the 6.5-kda prolipoprotein (rz1) which undergoes n-terminal signal sequence cleavage and post-translational lipid modification of the n-terminal cys of the mature protein. globomycin, the antibiotic which inhibits bacterial signal peptidase ii, specific for prolipoproteins containing diacylglyceryl cysteine [hayashi and wu, j. bioenerg. biomembr. 22 (1990) 451-471] inhibits the n-terminal sequence cleavage of ... | 1996 | 8626053 |
| conservation of the rd-bf-c2 organization in the pig mhc class-iii region: mapping and cloning of the pig rd gene. | the rd gene, named after the arginine (r) and aspartic acid (d) repeat in the central part of its protein, was initially mapped in the mouse h-2s subregion between c4 and bf. it was later mapped in the same position in the human mhc and here we show it is also conserved in the pig mhc class iii region, close to the complement bf gene. a pig rd genomic clone was isolated from a lambda-phage library. hybridizations on genomic dna separated with pulsed field gel electrophoresis identified common 22 ... | 1996 | 8624034 |
| long-circulating bacteriophage as antibacterial agents. | the increased prevalence of multidrug-resistant bacterial pathogens motivated us to attempt to enhance the therapeutic efficacy of bacteriophages. the therapeutic application of phages as antibacterial agents was impeded by several factors: (i) the failure to recognize the relatively narrow host range of phages; (ii) the presence of toxins in crude phage lysates; and (iii) a lack of appreciation for the capacity of mammalian host defense systems, particularly the organs of the reticuloendothelia ... | 1996 | 8622911 |
| interaction between the phage hk022 nun protein and the nut rna of phage lambda. | the nun gene product of prophage hk022 excludes phage lambda infection by blocking the expression of genes downstream from the lambda nut sequence. the nun protein functions both by competing with lambda n transcription-antitermination protein and by actively inducing transcription termination on the lambda chromosome. we demonstrate that nun binds directly to a stem-loop structure within nut rna, boxb, which is also the target for the n antiterminator. the two proteins show comparable affinitie ... | 1995 | 8618858 |
| disassembly of the coliphage lambda replication complex due to heat shock induction of the groe operon. | we have found previously that, in contrast to the free o initiator protein of lambda phage or plasmid rapidly degraded by the escherichia coli clpp/clpx protease, the lambda o present in the replication complex (rc) is protected from proteolysis. in amino acid-starved e. coli rela cells, a temperature shift from 30 to 43 degrees did not affect rc integrity, as judged from the unchanged level of stable lambda o observed; however, the same temperature shift in a complete medium resulted in the dec ... | 1996 | 8610451 |
| effects of dna heterologies on bacteriophage lambda packaging. | we have examined the impact of dna heterologies on the packaging of lambda dna in vitro. heterology-containing dna molecules were constructed by denaturing and reannealing a mixture of dna from ci+ phage and dna front phage carrying small insertion or deletion mutations in the ci gene. we found that molecules with heterologies of up to 19 base pairs (bp) can be packaged as viable heterozygous phage with approximately the same efficiency as molecules with a base pair mismatch. in contrast, with a ... | 1988 | 8608932 |
| effects of dna heterologies on bacteriophage lambda recombination. | previous studies of bacteriophage lambda recombination have provided indirect evidence that substantial sequence nonhomologies, such as insertions and deletions, may be included in regions of heteroduplex dna. however, the direct products of heterology-containing heteroduplex dna--heterozygous progeny phage--have not been observed. we have constructed a series of small insertion and deletion mutations in the ci gene to examine the possibility that small heterologies might be accommodated in hete ... | 1988 | 8608922 |
| exclusion of t4 phage by the hok/sok killer locus from plasmid r1. | the hok (host killing) and sok (suppressor of killing) genes (hok/sok) efficiently maintain the low-copy-number plasmid r1. to investigate whether the hok/sok locus evolved as a phage-exclusion mechanism, escherichia coli cells that contain hok/sok on a pbr322-based plasmid were challenged with t1, t4, t5, t7, and lambda phage. upon infection with t4, the optical density of cells containing hok/sok on a high-copy-number plasmid continued to increase whereas the optical density for those lacking ... | 1996 | 8606182 |
| identification of new fis binding sites by dna scission with fis-1,10-phenanthroline-copper(i) chimeras. | the chimeric nuclease fis-op has been used to identify novel fis binding sites. tethering the chemical nuclease op-cu+ to position 73 of the protein with a newly developed longer acetyl-beta-alanylamino spacer has facilitated the localization of two high-affinity fis binding sequences in a 3 kb puc19 plasmid. the shorter acetamido linker has allowed the chimeric nuclease to locate two strong fis binding sites in the 50 kb phage lambda genome. all four sites reside in biologically interesting loc ... | 1996 | 8605181 |
| cooperativity mutants of bacteriophage lambda ci repressor: temperature dependence of self-assembly. | analytical ultracentrifugation was used to study higher order self-assembly of lambda ci repressors, including eight mutants whose monomer to dimer reactions were recently characterized [burz et al. (1994) biochemistry 33, 8399]. six of the mutants were found to remain dimeric up to 50 microm total protein; the remaining mutants (ek102 and pt158) were found to undergo higher order oligomerization, as does wild-type ci. for these three repressors, we determined the stoichiometries and energetics ... | 1996 | 8605172 |
| computer-aided discrimination between active and inactive mutants of the n-terminal domain of the bacteriophage lambda repressor. | binding of the n-terminal domain of the lambda repressor to dna is coupled to dimerization. hydrophobic interactions between helix-5 and helix-5' drive the packing at the dimer interface. we have carried out computations of the conformational energy of packing of the fifth helices (and of the helix-4-loop-helix-5 portions) of variants of the lambda repressor operator binding domain, using an ecepp/3-based packing algorithm. here, we report the results for 26 mutants chosen among those that hve b ... | 1996 | 8604135 |
| cysticercosis: identification and cloning of protective recombinant antigens. | we describe the cloning and the evaluation of the protective capacity of 5 recombinant antigens expressed during the cysticercus stage of both taenia crassiceps and taenia solium. a cdna library was constructed in bacteriophage lambda zap using mrna isolated from larvae of t. crassiceps of the orf strain. the recombinant phage library was screened with polyclonal antibodies against 56- and 74-kda protective antigen fractions. this screening identified 13 recombinant clones, 5 of which were also ... | 1996 | 8604092 |
| nucleotide sequence and expression of the gene encoding nadp+- dependent glutamate dehydrogenase (gdha) from agaricus bisporus. | the gene encoding nadp+-dependent glutamate dehydrogenase (gdha) was isolated from an agaricus bisporus recombinant phage lambda library. the deduced amino acid sequence would specify a 457-amino acid protein that is highly homologous in sequence to those derived from previously isolated and characterized genes coding for microbial nadp+-gdh. the open reading frame is interrupted by six introns. none of the introns is located at either one of the positions of the two introns conserved in the cor ... | 1996 | 8602149 |
| identification, localization, and functional implications of an abundant nematode annexin. | cultures of the nematode c. elegans were examined for the presence of calcium-dependent, phospholipid-binding proteins of the annexin class. a single protein of apparent mass on sds-polyacrylamide gels of 32 kd was isolated from soluble extracts of nematode cultures on the basis of its ability to bind to phospholipids in a calcium-dependent manner. after verification of the protein as an annexin by peptide sequencing, an antiserum to the protein was prepared and used to isolate a corresponding c ... | 1996 | 8601586 |
| [growth of radiation resistance in bacteriophages as a result of intensifying expression of the stress system in host cells]. | by means of polyacrylamide gel electrophoresis (page) of proteins from radiation-resistant gamr mutants of escherichia coli, it was shown that induction and elimination of reca protein in these mutants are kinetically more rapid than in wild type cells, and heat-shock proteins (hsp) are hyperproduced even at a normal temperature (32 degrees c). gamma-and uv-irradiated bacteriophages were used to study the results of simultaneous enhanced expression of two stress repair systems. radiation-resista ... | 1995 | 8601508 |
| cleavage by rnase p of gene n mrna reduces bacteriophage lambda burst size. | rnase p, an enzyme essential for trna biosynthesis, can be directed to cleave any rna when the target rna is in a complex with a short, complementary oligonucleotide called an external guide sequence (egs). rnase p from escherichia coli can cleave phage lambda n mrna in vitro or in vivo when the mrna is in a complex with an egs. the egs can either be separate from or covalently linked to m1 rna, the catalytic rna subunit of rnase p. the requirement for mg2+ in the reaction in vitro is lower when ... | 1996 | 8600449 |
| high pressure represses expression of the malb operon in escherichia coli. | the formation of plaques by lambda phage in escherichia coli was prevented by elevated hydrostatic pressure; phage plaques were not detected at 30 mpa. furthermore, using promoter fragments derived from the malb operon, we showed that gene expression initiated from both promoters (malk-lamb and malefg) was repressed by elevated hydrostatic pressure. our findings suggest that high pressure affects gene expression directed by the malb regulatory interval, and this may cause a decrease in the quant ... | 1996 | 8598266 |
| role of escherichia coli rna polymerase alpha subunit in modulation of pausing, termination and anti-termination by the transcription elongation factor nusa. | the alpha subunit (alpha) of rna polymerase (rnap) is critical for assembly of polymerase and positive control of transcription initiation in escherichia coli. here, we report that alpha also plays a role in transcription elongation, and this involves a direct interaction between alpha and nusa factor. during in vitro transcription without nusa, alpha interacts with the nascent rna, as revealed by photocrosslinking. when nusa is present, rna crosslinks to nusa rather than to alpha. we show that ... | 1996 | 8598198 |
| quantitative dna fiber mapping. | the assembly of sequence ready, high-resolution physical maps and construction of minimally overlapping contigs for the human as well as model genomes requires accurate determination of the extent of overlap between adjacent clones as well as their relative orientation. this is presently done by procedures such as clone fingerprinting, southern blot analysis or clone end sequencing. we present a complementary analytical technique to map directly cloned dna sequences on to individual stretched dn ... | 1995 | 8595414 |
| direct automated sequencing of single lambda-phage plaques by exponential amplification sequencing. | 1995 | 8595004 | |
| nucleotide sequence of the schizosaccharomyces japonicus var. versatilis ribosomal rna gene cluster and its phylogenetic implications. | fission yeasts form a small but heterogeneous group of ascomycetes and it is still unclear whether they should be subdivided into three genera (schizosaccharomyces, octosporomyces, hasegawaea) or remain a single genus (schizosaccharomyces). in order to decide whether a new genus hasegawaea should be established for the species schizosaccharomyces japonicus and schizosaccharomyces versatilis, we have characterized the entire rdna cluster in schizosaccharomyces japonicus var. versatilis and compar ... | 1995 | 8590481 |
| solid-phase nested deletion: a new subcloning-less method for generating nested deletions. | we have developed a new subcloning-less method for generating nested deletions which we have termed solid-phase nested deletion. the basic procedure for this method is as follows. the target dna fragment is cloned in the multiple cloning site of a cloning vector, puc or its derivatives, and amplified by pcr using a set of primers, one of which is 5'-biotinylated. the amplified dna is partially digested by a restriction enzyme with a 4-base recognition sequence. the digested dna is ligated with a ... | 1995 | 8590281 |
| inhibition of transcription starting from bacteriophage lambda pr promoter during the stringent response in escherichia coli: implications for lambda dna replication. | replication of lambda plasmid dna is halted in amino acid-starved wild type (stringent) strains whereas it proceeds in rela (relaxed) mutants. the only transcription which could be important in lambda plasmid dna replication in amino acid-starved escherichia coli cells is that starting from the pr promoter. using a fusion which consists of the lacz gene under the control of bacteriophage lambda pr promoter we found that transcription starting from this promoter was inhibited during the stringent ... | 1995 | 8588470 |
| transformation of naturally competent streptococcus mutans with replicative and non-replicative tn916-containing plasmids: implications for a mechanism of transposition. | based on the observations reported here and what is known concerning transformation of naturally competent strains of s. mutans and other streptococcal species such as s. gordonii, we propose the model shown in figure 2. the tn916-intermediate transforms s. mutans as originally proposed for b. subtilis by scott and coworkers [8]. it is not clear in either system (b. subtilis or s. mutans) whether the tn916 intermediate enters the cell as ds-dna or ss-dna. because it is likely that transformation ... | 1995 | 8586174 |
| p1 clones from drosophila melanogaster as markers to study the chromosomal evolution of muller's a element in two species of the obscura group of drosophila. | thirty p1 clones from the x chromosome (muller's a element) of drosophila melanogaster were cross-hybridized in situ to drosophila subobscura and drosophila pseudoobscura polytene chromosomes. an additional recombinant phage lambda dsuby was also used as a marker. twenty-three (77%) of the p1 clones gave positive hybridization on d. pseudoobscura chromosomes but only 16 (53%) did so with those of d. subobscura. eight p1 clones gave more than one hybridization signal on d. pseudoobscura and/or d. ... | 1995 | 8585990 |
| interleukin-5 receptor alpha subunit gene regulation in human eosinophil development: identification of a unique cis-element that acts lie an enhancer in regulating activity of the il-5r alpha promoter. | further functional and biochemical characterization of the nuclear factor(s) which interacts with the eos1 enhancer-like element in the il-5r alpha promoter is currently in progress. since different transcription factors recognize and interact with dna in distinct fashions and with distinct structural motifs, we have modeled potential binding of the eos1 factor to its cis-element based upon its methylation interference pattern (fig. 2), using a cylindrical dna helical projection (fig. 6). over a ... | 1996 | 8585949 |
| the effects of trinucleotide repeats found in human inherited disorders on palindrome inviability in escherichia coli suggest hairpin folding preferences in vivo. | unusual dna secondary structures have been implicated in the expansion of trinucleotide repeat tracts that are associated with several human inherited disorders. we present evidence consistent with the folding of these trinucleotide repeats into hairpin loops at the center of a long dna palindrome in vivo. our assay utilizes a palindrome in bacteriophage lambda, the center of which determines its ability to inhibit plaque formation in a manner that is consistent with folding into a hairpin or cr ... | 1995 | 8582629 |
| chi recombination activity in phage lambda decays as a function of genetic distance. | in escherichia coli, chi is a recombination hotspot that stimulates recbcd-dependent exchange at and to one side of itself. chi activity is highest at chi and decreases with distance from chi. the decrease in chi activity may be a simple property of the physical distance over which chi can stimulate recombination. alternatively, the decay in chi activity with distance may reflect the high likelihood that chi-stimulated recombination occurs in a single chi-proximal act, to the exclusion of additi ... | 1995 | 8582627 |
| heterogeneous endolysins in listeria monocytogenes bacteriophages: a new class of enzymes and evidence for conserved holin genes within the siphoviral lysis cassettes. | listeria monocytogenes bacteriophages a118, a500 and a511 are members of three distinct phage groups with characteristic host ranges. their endolysin (ply) genes were cloned and expressed in escherichia coli as demonstrated by the conferred lytic phenotype when colonies of recombinant cells were overlaid with a lawn of listeria cells. the nucleotide sequences of the cloned dna fragments were determined and the individual enzymes (ply118, 30.8 kda; ply500, 33.4 kda; ply511, 36.5 kda) were shown t ... | 1995 | 8577256 |
| virus dna packaging: the strategy used by phage lambda. | phage lambda, like a number of other large dna bacteriophages and the herpesviruses, produces concatemeric dna during dna replication. the concatemeric dna is processed to produce unit-length, virion dna by cutting at specific sites along the concatemer. dna cutting is co-ordinated with dna packaging, the process of translocation of the cut dna into the preformed capsid precursor, the prohead. a key player in the lambda dna packaging process is the phage-encoded enzyme terminase, which is involv ... | 1995 | 8577244 |
| ribose catabolism of escherichia coli: characterization of the rpib gene encoding ribose phosphate isomerase b and of the rpir gene, which is involved in regulation of rpib expression. | escherichia coli strains defective in the rpia gene, encoding ribose phosphate isomerase a, are ribose auxotrophs, despite the presence of the wild-type rpib gene, which encodes ribose phosphate isomerase b. ribose prototrophs of an rpia genetic background were isolated by two different approaches. firstly, spontaneous ribose-independent mutants were isolated. the locus for this lesion, rpir, was mapped to 93 min on the linkage map, and the gene order zje::tn10-rpir-mel-zjd::tn10-psd-pura was es ... | 1996 | 8576032 |
| the human protoporphyrinogen oxidase gene (ppox): organization and location to chromosome 1. | we determined the structure of the human protoporphyrinogen oxidase (ppox) gene after isolation and characterization of lambda phage clones mapping discrete regions of the cdna. southern blotting of human genomic dna showed that there is a single copy of the ppox gene, and fluorescence in situ hybridization to metaphase chromosomes mapped the gene to region 1q22. the gene has 13 exons and about 8 kb. the exon/intron boundary sequences conform to consensus acceptor (gtn) and donor (nag) sequences ... | 1995 | 8575762 |
| suicide substrates reveal properties of the homology-dependent steps during integrative recombination of bacteriophage lambda. | a fundamental feature of bacteriophage lambda site-specific recombination is the strict requirement for a region of sequence identity between recombining dna duplexes. it has been difficult to understand how the recombination machinery identifies and responds to nonhomologies as subtle as a single base-pair substitution, because the reaction intermediates are transient and there are likely to be several different homology-dependent steps. in order to understand better how the recombination machi ... | 1995 | 8574589 |
| nondisruptive detection of activity of catabolic promoters of pseudomonas putida with an antigenic surface reporter system. | a simple procedure to detect the switching on and off of catabolic promoters of pseudomonas putida, at the level of single cells based on the immunodetection of a reporter epitope expressed on the surface of bacterial cells, has been developed. to do this, the antigenic sequence asp-leu-pro-pro-asn-ser-asp-val-val-asp, from a coronavirus, was inserted genetically in the permissive site around amino acid position 153 of the lamb protein (maltose and lambda phage receptor) of escherichia coli. whe ... | 1996 | 8572699 |
| quantitative fluorescence method for continuous measurement of dna hybridization kinetics using a fluorescent intercalator. | we present a quantitative fluorescence method for continuous measurement of dna or rna hybridization (including renaturation) kinetics using a fluorescent dna intercalator. the method has high sensitivity and can be used with reaction volumes as small as 1 microliter and amounts of dna around 1 ng. the method is based on the observations that (i) for the usual hybridization conditions, intercalators such as ethidium bromide bind (intercalate) to double-stranded dna (dsdna) but not single-strande ... | 1995 | 8572297 |
| structural analysis of mitochondrial dna molecules from fungi and plants using moving pictures and pulsed-field gel electrophoresis. | the size and structure of mitochondrial dna (mtdna) molecules was investigated by conventional and pulsed-field gel electrophoresis (pfge) and by analyzing moving pictures during electrophoresis of individual fluorescently labelled mtdna molecules. little or no mtdna that migrated into the gel was found in circular form for fungi (schizosaccharomyces pombe, saccharomyces cerevisiae and neurospora crassa) or plants (brassica hirta, tobacco, voodoo lily and maize). most mtdna migrated as a smear o ... | 1996 | 8568898 |
| impaired protein catabolism in trypanosoma cruzi-infected macrophages: possible involvement in antigen presentation. | the effect of trypanosoma cruzi infection on the ability of mature and immature murine peritoneal macrophage (mpm) subpopulations to catabolize the bacteriophage lambda repressor ci protein (ci) has been investigated. the capacity of infected mpm to present the ci and to stimulate various cd4+, i-ad- or i-ed-restricted t-cell hybridomas specific for ci was also assessed. our results show that the radioiodinated ci uptake and catabolism decreased sharply after infection of mpm with t. cruzi. a ci ... | 1995 | 8567032 |