Publications

highly repressible expression system for cloning genes that specify potentially toxic proteins.	a highly repressible expression vector system that allows the cloning of potentially deleterious genes has been constructed. undesired expression of a cloned gene was prevented (i) at the level of initiation of transcription, by the presence of the strong but highly repressible leftward promoter of bacteriophage lambda, lambda pl, and (ii) at the level of transcript elongation or translation, through synthesis of antisense rna complementary to the mrna of the cloned gene. the system was tested b ...	1987	2443481
genetically engineered diphtheria toxin fusion proteins carrying the hepatitis b surface antigen.	tripartite fusion proteins comprising the nontoxic mutant protein crm228 of diphtheria toxin (dt), the hepatitis b virus surface antigen (hbsag), and beta-galactosidase were obtained by expression of hybrid genes from the pr promoter of bacteriophage lambda and purification by affinity chromatography. the antigenicity and immunogenicity of the individual protein constituents were analyzed. a major neutralizing epitope of dt was inactivated by the hbsag insertion into the dt b fragment. the fusio ...	1987	2444498
molecular cloning and chemical synthesis of a region of platelet glycoprotein iib involved in adhesive function.	membrane glycoprotein (gp) iib-iiia is a component of a platelet adhesive protein receptor. a region of the heavy chain of gpiib, defined by the monoclonal antibody pmi-1, is involved in adhesion receptor function. we have localized and chemically synthesized this region of gpiib. a cdna clone that directs the synthesis of a fusion protein reactive with the pmi-1 antibody was isolated from a phage lambda gt11 expression library constructed with mrna from an erythroleukemia (hel) cell line. the d ...	1987	2444974
an elongation control particle containing the n gene transcriptional antitermination protein of bacteriophage lambda.	the n gene transcriptional antitermination protein of bacteriophage lambda is incorporated in vitro into transcriptional elongation complexes containing the e. coli proteins nusa and nusb. the binding of nusa to elongating rna polymerase is sequence-independent and follows the release of sigma 70. incorporation of n into the elongation complex requires an n utilization site (nut site) on the dna template. incorporation of nusb into the complex requires nusa, ribosomal protein s10, and the boxa c ...	1987	2445491
a rapid and improved method for generating cdna libraries in plasmid and phage lambda vectors.	we have developed a fast and efficient procedure for generating cdna libraries in plasmid or phage lambda vectors. we used mo-mulv reverse transcriptase to synthesize the first strand and directly added escherichia coli dna polymerase i with rnase h to synthesize the second strand. a special advantage of our procedure is the use of oligodeoxynucleotide adapters to insert the cdna into the vector, avoiding the use of methylating enzymes and subsequent digestion with massive amounts of restriction ...	1987	2445632
processing of escherichia coli 16s rrna with bacteriophage lambda leader sequences.	to test whether any specific 5' precursor sequences are required for the processing of pre-16s rrna, constructs were studied in which large parts of the 5' leader sequence were replaced by the coliphage lambda pl promoter and adjacent sequences. unexpectedly, few full-length transcripts of the rrna were detected after the pl promoter was induced, implying that either transcription was poor or most of the rrna chains with lambda leader sequences were unstable. nevertheless, sufficient transcripti ...	1987	2445728
induction of the heat shock regulon of escherichia coli markedly increases production of bacterial viruses at high temperatures.	production of bacteriophages t2, t4, and t6 at 42.8 to 44 degrees c was increased from 8- to 260-fold by adapting the escherichia coli host (grown at 30 degrees c) to growth at the high temperature for 8 min before infection; this increase was abolished if the host htpr (rpoh) gene was inactive. others have shown that the htpr protein increases or activates the synthesis of at least 17 e. coli heat shock proteins upon raising the growth temperature above a certain level. at 43.8 to 44 degrees c ...	1988	2446014
molecular cloning of a gene encoding a 45,000-dalton polypeptide associated with bile acid 7-dehydroxylation in eubacterium sp. strain vpi 12708.	eubacterium sp. strain vpi 12708 is an intestinal anaerobic bacterium which possesses an inducible bile acid 7-dehydroxylation activity. two cholic acid-induced polypeptides with apparent molecular weights of 27,000 and 45,000, respectively, coeluted with bile acid 7-dehydroxylation activity upon anaerobic high-performance gel filtration chromatography of crude cellular protein extracts. the 45,000-dalton polypeptide was purified to greater than 95% homogeneity by high-performance liquid chromat ...	1988	2448288
overproduction of an antisense rna containing the oop rna sequence of bacteriophage lambda induces clear plaque formation.	we have constructed an iptg-inducible plasmid which overexpresses oop rna sequences in escherichia coli. infection of these transformed e. coli cells (sb221/poop5) with lambda+ phage produced clear plaques, whereas lambda+ infection of cells transformed with the plasmid vector (sb221/pjdc406) or the plasmid expressing the oop rna transcript in the other orientation (sb221/poop9) gave rise to turbid plaques characteristic of lambda+. calculations of the percentage of infected cells forming lysoge ...	1987	2448589
phage lambda and the regulation of transcription termination.		1988	2449971
generation and characterization of monoclonal antibodies to 28-, 35-, and 65-kilodalton proteins of mycobacterium tuberculosis.	three monoclonal antibodies (h60.15, h61.3, and h105.10) directed to protein antigens of mycobacterium tuberculosis were obtained and characterized. h60.15 recognizes a protein with a molecular mass of 28 kilodaltons (kda) with broad cross-reactivity on a panel of 12 species and strains of mycobacteria. h61.3 reacts with a 35-kda protein present in m. tuberculosis, mycobacterium bovis bcg, and m. africanum. on the basis of the antigen molecular masses and competition experiments with other monoc ...	1988	2451641
mutagenesis of bleomycin-damaged lambda phage in sos-deficient and repair endonuclease-deficient escherichia coli.	previous dna sequence analysis of bleomycin-induced forward mutations in repackaged lambda phage has suggested sos-dependent replicative bypass of oxidized apyrimidinic sites as a possible mechanism of mutagenesis. in order to evaluate this hypothesis further, frequencies of mutation to a clear-plaque phenotype were compared for bleomycin-damaged phage grown in various repair-deficient strains of escherichia coli. survival of bleomycin-damaged phage was virtually identical in all host strains. s ...	1988	2453358
cloning and expression of taenia ovis antigens in escherichia coli.	double stranded dna complementary to poly(a)+ mrna from the tapeworm taenia ovis was cut with sau 3a to an average length of about 300 bp and inserted into the bam hi site of the expression plasmids pex1, pex2 and pex3. these plasmids express a hybrid protein derived from a fusion of the cro gene with the lac z gene (truncated at its 5' end by 53 bp) of phage lambda. cloning sites lie downstream from the gene fusion. escherichia coli infected with another plasmid (pci857) bearing the temperature ...	1988	2453801
[regulation of expression of the escherichia coli htpr gene by antisense rna].	a vector plasmid directing the synthesis of antisense rna of escherichia coli gene htpr has been constructed. for this fragment of htpr gene encoding the synthesis of n-terminal sequence of htpr protein has been cloned in this plasmid in the opposite orientation under the control of pr promoter of bacteriophage lambda. under conditions of pr transcription the induction the growth of bacterial cells carrying the recombinant plasmid was delayed and the rate of degradation of puromycin polypeptides ...	1988	2455865
cloning and expression of the mspi restriction and modification genes.	the genes for the mspi restriction (r) and modification enzymes (recognition sequence ccgg) have been cloned into escherichia coli using the vector pbr322. clones carrying both genes have been isolated from libraries prepared with ecori, hindiii and bamhi. the smallest fragment that encodes both activities is a 3.6-kb hindiii fragment. plasmids purified from the clones are fully resistant to digestion by mspi, indicating that the modification gene is functional in e. coli. the clones remain sens ...	1988	2456254
engineered recombinant messenger rna can be replicated and expressed inside bacterial cells by an rna bacteriophage replicase.	in this paper we describe how an rna replicase can be "tricked" into recognizing, binding to, and replicating host-cell message rnas. in our system, the gene encoding q beta replicase is constitutively expressed from a plasmid vector present in an escherichia coli host, while a second plasmid directs the transcription of a replication-competent, phage-like template rna. this 680 nucleotide transcript (n- rna) contains specific sequences required for q beta replicase function. included within thi ...	1988	2456396
rna-primed initiation sites of dna replication in the origin region of bacteriophage lambda genome.	using dna molecules synthesized in the early stage of lambda phage infection, deoxynucleotides at the transition sites from primer rna to dna synthesis have been mapped in the 1.5 kbase area of the lambda phage genome containing the genetically defined replication origin (ori lambda). sites in the 1-strand (the polarity of the 1-strand is 5' to 3' from the left to the right direction of the lambda phage genetic map) were distributed both inside and outside of the ori lambda, whereas the sites in ...	1988	2456527
common epitopes of glycoprotein b map within the major dna-binding proteins of bovine herpesvirus type 2 (bhv-2) and herpes simplex virus type 1 (hsv-1).	bovine herpesvirus 2 (bhv-2) specifies a glycoprotein of 130 kda (gb bhv-2) which shows extensive homology to glycoprotein b (gb-1) of herpes simplex virus 1 (hsv-1). the bhv-2-specific 130-kda glycoprotein is able to induce cross-reacting antibodies, some of which even cross-neutralize hsv-1. in order to determine the genome localization of gb bhv-2 and in order to identify conserved antigenic domains in both glycoproteins, we established libraries of subgenic fragments of bhv-2 and hsv-1 dna i ...	1988	2457278
regulation of proteolysis in escherichia coli cells by antisense rna of htpr gene.	a new vector has been constructed on the basis of plasmid pcqv2 containing thermoinducible regulatory elements of bacteriophage lambda. the vector makes it possible to combine an inducible synthesis of foreign proteins with negative control of intracellular proteolysis. the principle employed for the construction of the plasmid implies the regulation of gene expression by antisense rnas. in the sali restriction site of pcqv2 a fragment of htpr gene encoding the n-terminal region of the polypepti ...	1988	2457382
monoclonal antibodies to a proenkephalin a fusion peptide synthesized in escherichia coli recognize novel proenkephalin a precursor forms.	monoclonal antibodies have been generated to a chimeric peptide comprised of escherichia coli beta-galactosidase fused to the amino acid sequence 69-207 of human preproenkephalin a. two monoclonal antibodies, pe-1 and pe-2, were identified by their ability to recognize the same segment of proenkephalin a fused to the cii gene product of the e. coli bacteriophage lambda. the binding domains of pe-1 and pe-2 have been broadly located, with respect to the primary translation product, within the ami ...	1988	2461943
distal ccaat box deletion in the a gamma globin gene of two black adolescents with elevated fetal a gamma globin.	point mutations in g gamma and a gamma globin gene promoters are associated with increased production of g gamma and a gamma globin, respectively. to determine whether an upstream promoter mutation could account for elevated a gamma in a black adolescent with a gamma-beta+-hpfh and sickle cell trait, we cloned the 13 kb bglii fragment containing both gamma genes into phage lambda vector embl3. for one clone, the a gamma upstream promoter showed no hybridization to a 19 bp oligonucleotide whose s ...	1988	2462713
characterization of mrna species related to human liver cytochrome p-450 nifedipine oxidase and the regulation of catalytic activity.	p-450nf is the major enzyme in human liver involved in the metabolism of the calcium-channel blocker nifedipine. by screening a bacteriophage lambda gt11 expression library, a cdna clone designated nf 10 with an insert length of 2.8 kilobases (kb) was isolated. this clone was sequenced and found to be highly similar in its overlapping section with sequences of two other cdna clones previously isolated from the same expression library, nf 25 (beaune, p. h., umbenhauer, d. r., bork, r. w., lloyd, ...	1989	2463251
construction of onchocerca volvulus cdna libraries and partial characterization of the cdna for a major antigen.	adult onchocerca volvulus were isolated from nodules removed from onchocerciasis patients at four locations--two in the west african sudan-savanna region (near bamako, mali, and touboro, cameroon), one in a west african forest region (kumba, cameroon) and one near guatemala city, guatemala. four different cdna expression libraries were constructed in bacteriophage lambda gt11 using poly(a)+ rna from the adult female worms. individual cdna clones of single copy genes were used to compare the geno ...	1988	2464764
single-shot cloning of multiple cdnas coding for a set of related microtubule-associated proteins.	we describe a method for isolating multiple cdna clones coding for a set of related proteins from bacteriophage lambda expression libraries in a single screening with polyclonal antiserum. the antiserum is raised against a tissue sub-fraction containing the proteins of interest; in the example presented this was brain microtubules. each antibody-positive clone from the lambda expression library is plaque-purified and then grown in contact with nitrocellulose membrane that becomes coated with pro ...	1988	2465208
the gene coding for the 190,000-dalton iron-regulated protein of yersinia species is present only in the highly pathogenic strains.	a genomic library containing dna fragments of 0.5 to 2 kilobase pairs in length from yersinia enterocolitica serovar o:8 was constructed in a bacteriophage lambda gt11 expression vector. mouse antibodies specific for the iron-regulated high-molecular-weight proteins (hmwps) were used to screen the library. two positive clones of 1 and 0.5 kilobase pairs, designated a13 and d7, respectively, were detected and isolated. they coded for beta-galactosidase fusion proteins of 151,000 and 138,000 dalto ...	1989	2466794
analysis of mycobacterium tuberculosis genoma and production of a recombinant protein containing specific b and t cell antigenic determinants--new approaches to second generation antituberculosis vaccines.	tuberculosis is still a major health problem in almost all over the world. thus, new directions in basic and applied research of tuberculosis are under investigation in several laboratories. in this paper, we provide recent data obtained in our laboratory with the recombinant dna technology which allow a systematic survey of the microbial genome. screening of the m. tuberculosis genomic dna library in the phage lambda gt11 expression vector, using e. coli as surrogate host, has evidenced the pos ...	1989	2467445
antisense rna does not significantly affect expression of the galk gene of escherichia coli or the n gene of coliphage lambda.	the effect of antisense rna on the expression of genes galk and n was studied in vivo. these two genes were either present in the escherichia coli chromosome, as single copies, or were cloned on plasmid vectors. antisense rna was supplied from multicopy vectors where the entire galk or n gene, or only their n-proximal portions, were cloned in the antisense orientation downstream from the strong pl, pr or laczp promoters. in all of the experiments there was no significant inhibition of the galk o ...	1988	2468564
molecular cloning of eel growth hormone cdna and its expression in escherichia coli.	cdna clones coding for growth hormone (egh) of japanese eel (anguilla japonica) have been isolated from a cdna library prepared from pituitary gland poly(a)+ rna. the nucleotide sequence of the egh cdna was determined. it codes for the prehormone of 209 amino acids (aa) including a putative signal peptide of 19 aa. the deduced amino acid sequence was identical with that determined for egh protein. the primary structure of egh was compared with those of other species growth hormones (chum salmon, ...	1988	2468582
isolation and characterization of the human chorionic gonadotropin beta subunit (cg beta) gene cluster: regulation of transcriptionally active cg beta gene by cyclic amp.	the alpha and beta subunit genes encoding chorionic gonadotropin (cg) are regulated transcriptionally in placental cells by cyclic amp (camp). the regulatory response sequences of the alpha gene have been studied extensively. similar studies of the cg beta subunit (cg beta) gene have not been possible because transcriptionally active sequences have not been identified in the clones isolated to date. the cg beta subunit genes form a complex cluster of seven structurally similar genes that include ...	1988	2468994
two variant surface glycoprotein genes distinguish between different substrains of trypanosoma brucei gambiense.	trypanosoma brucei gambiense differs from other t. brucei subspecies in the stability and conservation of its bloodstream form antigenic repertoire. two variant surface glycoprotein (vsg) cdna clones corresponding to the antigens u1 and l2 were isolated from t. b. gambiense bacteriophage lambda gt11 expression libraries and characterized. a third vsg cdna clone, p1, was also examined. the l2 and u1 vsg genes are present in a large number of t. b. gambiense stocks isolated over a thirty-year peri ...	1989	2469013
translation products of cauliflower mosaic virus orf v, the coding region corresponding to the retrovirus pol gene.	open reading frame (orf) v of cauliflower mosaic virus (camv), the candidate for the reverse transcriptase gene, has been expressed in e. coli under control of the pr promoter of bacteriophage lambda either as an n-terminal polypeptide fused to beta-galactosidase or as the total orf v without fusion. antibodies against these proteins were used to analyze extracts from camv-infected plants by immunoblotting. orf v-specific polypeptides of 80, 62, 58, 22, and 18 kd apparent molecular weights were ...	1987	2469252
a versatile phage lambda expression vector system for cloning in escherichia coli.	by integrating fragments from the expression plasmids pjk2 and pjk4 into a derivative of the bacteriophage lambda, we constructed the phage expression vectors lambda jk2 and lambda jk4, which allow efficient cloning of genomic or cdna either into the 5' end or the 3' end of the lacz gene of escherichia coli. expression of barrier-free dna in phase may lead to fusion proteins consisting of active beta-galactosidase (beta gal) plus an additional polypeptide encoded by the inserted dna. analysis of ...	1989	2469628
analysis of apolipoprotein e7 (apolipoprotein e-suita) gene from a patient with hyperlipoproteinemia.	we have isolated and analyzed apolipoprotein e7 gene from a patient with hyperlipoproteinemia. apolipoprotein e7 (apolipoprotein e-suita) is a variant of apolipoprotein e with four additional units of positive charge compared to apolipoprotein e3, which is the major isoform of apolipoprotein e. the heterozygous gene of apolipoprotein e7/3 from the patient was cloned into lambda phage. the cloned apolipoprotein e genes were subcloned into a murine retrovirus shuttle vector and were expressed. two ...	1989	2470732
antisense rna: effect of ribosome binding sites, target location, size, and concentration on the translation of specific mrna molecules.	a series of plasmids were constructed to generate rna complementary to the beta-galactosidase messenger rna under control of the phage lambda pl promoter. these plasmids generate anti-lacz mrna bearing or lacking a synthetic ribosome binding site adjacent to the lambda pl promoter and/or the lacz ribosome binding site in reverse orientation. fragments of lacz dna from the 5' and/or the 3' region were used in these constructions. when these anti-mrna molecules were produced in escherichia coli 29 ...	1989	2472339
construction of directional cdna libraries enriched for full-length inserts in a transcription-competent vector.	we have designed a simple procedure for the construction of directional cdna libraries enriched for full-length inserts in a transcription-competent cloning vector. an oligonucleotide, its 5' end starting with a heteropolymeric sequence encoding the rare restriction sites for noti and sfii, followed by 50 dt residues, is used to prime first-strand synthesis on size-selected mrna. after second-strand synthesis and ecori linker addition, the cdna is double digested with ecori and noti, or with eco ...	1989	2473019
cloning and analysis of the gene for the major outer membrane lipoprotein from pseudomonas aeruginosa.	the gene for the pseudomonas aeruginosa outer membrane lipoprotein i was isolated from a genomic library in the phage lambda embl3 vector and subsequently subcloned in the low copy-number, wide host-range plasmid vector, pkt240. the cloned gene was highly expressed, resulting in the production of a low molecular-weight protein (8 kd) that was found to be associated with the outer membrane. sequence analysis showed an open reading frame of 83 amino acids with a putative n-terminal hydrophobic sig ...	1989	2473376
molecular cloning and expression of a t-cell stimulating membrane protein of francisella tularensis.	the isolation and expression in escherichia coli of a gene encoding a t-cell stimulating 17 kilodalton (kda) membrane protein of francisella tularensis is described. a genomic library of dna from the live vaccine strain lvs of f. tularensis was constructed in the e. coli expression vector phage lambda gt11. the library was probed with antibodies directed against the 17 kda protein. one recombinant phage was isolated, containing a 2.8 kilobase (kb) dna insert. the insert was cleaved and a resulti ...	1989	2475738
identification of a maltose-inducible major outer membrane protein in actinobacillus (haemophilus) pleuropneumoniae.	the addition of maltose to the growth media of actinobacillus pleuropneumonia (serotype 1) resulted in the induction of an outer membrane protein (omp) with a molecular mass of 42 kda. this protein had porin-like properties in that it was peptidoglycan-associated and was resistant to proteolysis by trypsin. a pleuropneumoniae expressing the 42 kda omp were unable to bind lambda phage. similar proteins were also induced in a. pleuropneumoniae isolates representing serotypes 2 to 7 with the except ...	1989	2475740
dna base changes and rna levels in n-acetoxy-2-acetylaminofluorene-induced dihydrofolate reductase mutants of chinese hamster ovary cells.	formerly, we isolated a series of dihydrofolate reductase-deficient chinese hamster ovary cell mutants that were induced by n-acetoxy-2-acetylaminofluorene. deletions and complex gene rearrangements were detected in 28% of these mutants; 72% contained putative point mutations. in the present study, we have localized the putative point mutations in the 25,000 base dhfr gene by rnase heteroduplex mapping. assignment of a position for each mutation was successful in 16 of 19 mutants studied. we clo ...	1989	2477551
[polymerization of dna fragments coding epitopes of the surface antigen of hepatitis b in escherichia coli cells].	synthetic oligonucleotides coding for the amino acid residues 135-151 (a, b) and 93-109 (c) of the hepatitis b surface antigen (hbsag) have been polymerized. the obtained polymers (ac)n and (bcac)n were inserted into the beginning of the lacz gene under the control of the chloramphenicol promoter or the right promoter pr of bacteriophage lambda. stability of the obtained plasmids was investigated during transformation, cell growth and gene expression.	1989	2482440
use of the polymerase chain reaction for the differential cross screening of libraries cloned into phage-lambda-based vectors.	we describe a simple and rapid method that can be used to identify sequences present in any two dna libraries (either genomic or cdna), provided only that the libraries are in different vectors with different cloning sites. this procedure makes use of the polymerase chain reaction (pcr) to amplify the inserts of one library. the product of the pcr reaction is then used to screen a second library to identify sequences which are common to both. we illustrate the use of this method for the systemat ...	1989	2482827
identification of cdna clones that code for protein-tyrosine kinases by screening expression libraries with antibodies against phosphotyrosine.	a phage lambda gt11 human fibroblast cdna expression library was screened with antibodies against phosphotyrosine to determine the feasibility of this approach as a method for the identification of clones that code for protein-tyrosine kinases. several antibody positive clones were isolated. one clone also scored positive with degenerate oligonucleotides designed to identify sequences coding for protein-tyrosine kinases. this cdna clone was partially sequenced and proved to be identical to part ...	1988	2485256
human cysticercosis and taeniasis: molecular approaches for specific diagnosis and parasite identification.	the construction and antibody screening of taenia solium cdna libraries, generated in the escherichia coli bacteriophage lambda gt11, with the identification of clones putatively expressing antigen b, t. solium-specific and other antigens is described. lysogens were produced from a number of selected clones and beta-galactosidase fusion peptides ranging in mr of approximately 135,000-150,000 were demonstrated. these proteins were shown by immunoblotting to be reactive with a pool of sera from cy ...	1989	2489006
autoimmunity in lyme disease: molecular cloning of antigens recognized by antibodies in the cerebrospinal fluid.	in inflammatory disease of the central nervous system (cns), oligoclonal bands of immunoglobulin with restricted heterogeneity can often be observed in cerebrospinal fluid (csf) samples. these antibodies can be directed against the disease inducing pathogen or might be autoreactive and involved in the process of brain inflammation and demyelination. we used a molecular biology approach to characterize these antibody responses in patients with lyme disease. this disorder is caused by infections w ...	1989	2491615
structure of the gene for human plasminogen activator inhibitor-2. the nearest mammalian homologue of chicken ovalbumin.	plasminogen activator inhibitor-2 (pai-2) can regulate the formation of plasmin by inhibiting urokinase and tissue plasminogen activator. pai-2 is induced in monocytes and endothelium by inflammatory mediators, and it is made in the placenta during pregnancy. pai-2 is a member of the serine protease inhibitor gene family, and it is particularly similar to chicken ovalbumin. like ovalbumin, pai-2 is secreted without cleavage of a signal peptide. to determine the structure of the pai-2 gene, two b ...	1989	2494165
cloning, sequence analysis and transcriptional study of the isopenicillin n synthase of penicillium chrysogenum as-p-78.	a gene (ips) encoding the isopenicillin n synthase of penicillium chrysogenum as-p-78 was cloned in a 3.9 kb sali fragment using a probe corresponding to the amino-terminal end of the enzyme. the sali fragment was trimmed down to a 1.3 kb ncoi-bglii fragment that contained an open reading frame of 996 nucleotides encoding a polypeptide of 331 amino acids with an mr of 38012 dalton. the predicted polypeptide encoded by the ips gene of strain as-p-78 contains a tyrosine at position 195, whereas th ...	1989	2499766
[construction of promoter-probe vectors on the basis of a modified beta-galactosidase gene of escherichia coli].	plasmid-based promoter-probe vectors ppv4 and ppv5 have been constructed which are useful for comparing the relative efficiencies of bacterial promoters. the vectors utilize the beta-galactosidase (lacz) gene of e. coli as an indicator gene. the latter was modified using synthetic dna fragments. the promotor-probe system contains the ampicillin resistance gene and the origin of replication of plasmid pbr322. the plasmids ppv4 and ppv5 carry clustered unique restriction sites usable for promoter ...	1989	2500937
construction and phosphorylation of a fusion protein hu-ifn-alpha a/gamma.	a protein consisting of human (hu)-ifn-alpha a to which the cooh-terminal 16 amino acids of hu-ifn-gamma were fused was prepared by constructing an expression vector by oligonucleotide-directed mutagenesis. the hybrid protein hu-ifn-alpha a/gamma was expressed under the control of phage lambda pl promoter. the protein was purified with the use of a monoclonal antibody against hu-ifn-alpha or the cooh-terminal amino acid sequence of hu-ifn-gamma. the purified protein exhibited a single major band ...	1989	2502045
structure of the canine pancreatic lipase gene.	identification of three overlapping clones in a canine genomic lambda phage library allowed us to determine a detailed restriction enzyme map of the primary transcriptional unit of the pancreatic lipase gene (15.5 kilobase pairs) as well as 15 and 6 kilobase pairs of 5'- and 3'-flanking regions, respectively. dna sequence analysis provided the primary structure of (a) 1,345 nucleotides (nt) of 5'-flanking sequence including caat and tata boxes at positions -112 and -35, respectively, and a class ...	1989	2502543
localization, cloning, and expression of genetic determinants for bacteriophage resistance (hsp) from the conjugative plasmid ptr2030.	genetic determinants for a bacteriophage resistance mechanism (hsp+) encoded by plasmid ptr2030 (46.2 kilobases [kb]) were localized by mapping an 11.5-kb deletion that accompanied the transition of lactococcus lactis lma12-4 transconjugants (m. e. sanders, p. j. leonard, w. d. sing, and t. r. klaenhammer, appl. environ. microbiol. 52:1001-1007, 1986) from phage resistance to phage sensitivity. the deleted 34.7-kb replicon (ptr2023, hsp-) retained its conjugative ability, demonstrating that the ...	1989	2504114
salmonella typhimurium metc operator-constitutive mutations.	we used an escherichia coli lac deletion strain lysogenized with a metc-lacz fusion phage (lambda clac) to select operator-constitutive mutations in the salmonella typhimurium metc gene control region. the mutations were located in a region containing 2 tandemly repeated 8 bp palindromes previously proposed to be the metj repressor binding site. lysogens carrying lambda clac mutant phage exhibit high beta-galactosidase levels that are only partially repressible by methionine. the results suggest ...	1989	2506106
cloning and dna sequence analysis of a lactococcus bacteriophage lysin gene.	a gene for the lysin of lactococcus lactis bacteriphage phi vml3 was cloned using an escherichia coli/bacteriophage lambda host-vector system. the gene was detected by its expression of antimicrobial activity against l. lactis cells in a bioassay. the cloned fragment was analysed by sub-cloning on to e. coli plasmid vectors and by restriction endonuclease and deletion mapping. its entire dna sequence was determined and an open reading frame for the lysin structural gene was identified. the seque ...	1989	2506424
the cloned polc gene of bacillus subtilis: characterization of the azp12 mutation and controlled in vitro synthesis of active dna polymerase iii.	wild type (wt) bacillus subtilis polc and polcazp12, a mutant derivative specifying a form of dna polymerase iii resistant to hydroxyphenylazopyrimidines, were cloned as genomic fragments approximating the length required to encode the entire polymerase. the cloned dna fragments were subjected to restriction and partial sequence analysis to locate the 5' end of the polc-specific coding sequence and the azp12 mutation, which was identified as a t----g transversion specifying replacement of serine ...	1989	2515995
[interference of inducible repair processes in escherichia coli].	radiation and the majority of chemical mutagens produce lesions in the dna of cells which provoke the induction--as a reverse response--of some inducible repair processes. one of them is the adaptive response--highly specific in the repair of damages, induced by alkylating agents. this repair pathway decreases the toxic and mutagenic effects of many alkylating agents and can be induced in escherichia coli cells exposed to sublethal concentrations of the same agents. by contrast, the sos repair p ...	1989	2517492
isolation and characterization of a rhizobium loti gene required for effective nodulation of lotus pedunculatus.	a rhizobium loti gene required for effective invasion of the host lotus pedunculatus has been identified by transposon tn5 mutagenesis. cosmids that complemented a previously isolated mutation (239) at this invasion (inv) locus were identified by in planta complementation and used to construct a physical map of the gene region. the insertion site of tn5 in pn239 was mapped to a 7.5-kb ecori fragment, which complemented the mutation when subcloned into plafr1. further tn5 mutagenesis of the 7.5-k ...	1989	2520823
retroregulation of the bacteriophage lambda int gene: limited secondary degradation of the rnase iii-processed transcript.	expression of the int gene of bacteriophage lambda from two promoters, pi and pl, is differentially regulated through rna processing. efficient int protein synthesis from the pl rna is inhibited by the action of sib, a cis-acting retroregulator downstream from the int gene. we have used mapping procedures with nuclease s1 to study the pl transcripts produced in vivo after phage lambda infection. we have found an rnase iii-dependent processing site within the int coding sequence, 387 nucleotides ...	1989	2521618
repression of transcription from the b2-att region of coliphage lambda by integration host factor.	the central b2-att region of coliphage lambda is known to be transcriptionally active in vitro, but silent in vivo in lambda lysogens. to explain such in vivo repression of transcription originating in the b2-att region, we explored the effect of the escherichia coli integration host factor (ihf), the product of e. coli genes hima and himd, especially since the att region contains several ihf-binding sites. using various lambda dna templates, we mapped the transcripts which are initiated in vitr ...	1989	2521754
dna looping induced by bacteriophage lambda o protein: implications for formation of higher order structures at the lambda origin of replication.	a plasmid has been constructed, pori2, which contains two lambda replication origin sequences separated by 1068 bp; both lambda sequences having the same orientation. when lambda initiation protein o is reacted with linearized pori2 and examined by electron microscopy it is found to contain a looped area in which two parts of the plasmid are bound together by the o protein complex. length measurements show that the o protein binds at the expected positions of the lambda origin sequences and that ...	1989	2521755
phage lambda cro protein and ci repressor use two different patterns of specific protein-dna interactions to achieve sequence specificity in vivo.	by assaying the binding of wild-type cro to a set of 40 mutant lambda operators in vivo, we have determined that the 14 outermost base pairs of the 17 base pair, consensus lambda operator are critical for cro binding. cro protein recognizes 4 base pairs in a lambda operator half-site in different ways than ci repressor. the sequence determinants of cro binding at these critical positions in vivo are nearly perfectly consistent with the model proposed by w. f. anderson, d. h. ohlendorf, y. takeda ...	1989	2521838
structural analysis of the carboxy terminus of bacteriophage lambda repressor determined by antipeptide antibodies.	to analyze lambda repressor function and structure, antibodies were generated with synthetic peptides corresponding to sequences believed to be involved in prophage induction. these site-directed antibodies seemed to recognize preferentially the primary sequence of repressor because they reacted better in competition experiments with the oligopeptide and with the partially denatured forms of repressor than with the native molecules. this information, together with the characteristic ability of t ...	1989	2522089
escherichia coli dnak and grpe heat shock proteins interact both in vivo and in vitro.	previous studies have demonstrated that the escherichia coli dnak and grpe genes code for heat shock proteins. both the dnak and grpe proteins are necessary for bacteriophage lambda dna replication and for e. coli growth at all temperatures. through a series of genetic and biochemical experiments, we have shown that these heat shock proteins functionally interact both in vivo and in vitro. the genetic evidence is based on the isolation of mutations in the dnak gene, such as dnak9 and dnak90, whi ...	1989	2522091
expression of human parathyroid hormone in escherichia coli.	human parathyroid hormone (pth) has been expressed in escherichia coli as a cro-beta-galactosidase-hpth fusion protein under temperature-sensitive control of the lambda phage pr promoter. the lacz gene has been truncated to a different extent revealing an optimal length of the prokaryotic peptide portion between 199 and 407 amino acid residues. up to 250 mg of pure fusion protein have been obtained from 1-liter e. coli culture by stepwise solubilization with urea. the linkage between the prokary ...	1989	2522444
structure and inherent properties of the bacteriophage lambda head shell. vi. dna-packaging-defective mutants in the major capsid protein.	some amino acid substitutions in the major capsid protein (gene e product) of lambda phage are found to cause a defect in dna packaging. these substitutions permit initiation of dna packaging and expansion of the prohead. however, cleavage of the concatemer dna at the cos site takes place only to a very small extent, and the capsid eventually becomes empty. interestingly, the mutations are suppressed by a decrease of the dna length between the cos sites by 8000 to 10,000 bases. these properties ...	1989	2522554
lambda phage shuttle vectors for analysis of mutations in mammalian cells in culture and in transgenic mice.	foreign dna sequences contained in lambda bacteriophage genomes integrated in mammalian dna can be efficiently rescued into infectious phage particles by treatment of the mammalian dna with lambda-packaging extracts prepared in e. coli. this system provides for rapid, non-selective recovery of stably integrated, chromosomal sequences into lambda phage for subsequent analysis in bacterial systems. since rescue is prior to selection, mutations can be recovered from intact animals made transgenic f ...	1989	2522589
[lethal and mutagenic effect of incorporated 6-3h-pyrimidines on extracellular phage lambda].	a study was made of lethal and mutagenic effects of 6-3h-thymidine and 6-3h-cytosine, incorporated into dna, on extracellular phage lambda. the lethal effects of both 6-3h-pyrimidines (the number of lethal hits per 3h decay) do not differ from those of [3h-methyl]thymidine and 5-3h-cytosine. the mutagenic effects (at equal survival rates) are as follows: 6-3h-thymidine approximately 3h2o less than [3h-methyl]thymidine less than 6-3h-cytosine less than 5-3h-cytosine. uv-irradiation of host cells ...	1989	2522663
lambda repressor mutants that are better substrates for reca-mediated cleavage.	reca-mediated cleavage of the bacteriophage lambda repressor results in inactivation of the protein and leads to induction of the lambda prophage. here, we report the identification of three mutations in lambda repressor that significantly increase the rate of reca-mediated cleavage. these mutations were isolated as intragenic second-site suppressors of a mutation (ind-) which prevents cleavage. purified repressor proteins that contain both the ind- mutation and one of the second-site mutations ...	1989	2522996
genetic analysis of bacteriophage lambda ciii gene: mrna structural requirements for translation initiation.	the bacteriophage lambda ciii gene product regulates the lysogenic pathway. the ciii gene is located in the leftward operon, which is transcribed from the pl promoter. we have previously shown (s. altuvia and a. b. oppenheim, j. bacteriol. 167:415-419, 1986) that mutations that show elevated expression lie within the ciii coding sequence. we isolated mutants that show decreased ciii activity. all the mutations were found to cause a drastic reduction in the rate of initiation of ciii translation. ...	1989	2523380
induction of lambda prophage near the site of focused uv laser radiation.	dna damage from photon scatter or beam spread during uv excimer laser irradiation was investigated using the induction of bacteriophage lambda in e. coli br339. prophage induction in these cells leads to the production of beta-galactosidase which can be detected colorimetrically by the application of appropriate substrates. an agar surface overlayed with br339 cells was placed at various distances from the focal point of a converging lens and exposed to either 193 or 248 nm laser radiation. ener ...	1989	2523542
efficient simplified cosmid cloning: construction and characterization of cosmid vectors that carry the two cohesive end sites of lambda phages arrayed in tandem.	we constructed a series of cosmid vectors that carry the two cohesive end sites (cos) of lambda phage, arrayed in tandem, which enabled us to clone fragments of genomic dna of up to 50 kb without a vector background. an equimolar mixture of the left and right vector arms of equal length was prepared from the vector dna, simply by treating the dna sequentially with three enzymes, restriction enzyme pvuii, alkaline phosphatase, and restriction enzyme bamhi (or bglii), without purification by agaro ...	1989	2523674
footprint of the sigma protein.	escherichia coli rna polymerase is a multi-subunit enzyme that catalyzes rna synthesis, using dna as a template. the sigma subunit of this enzyme plays an important role in the recognition of promoter sites on dna. using dnase i footprinting, we have found that in the absence of the other subunits, sigma binds specifically to the bacteriophage lambda pr promoter dna sequence. in the presence of the sigma subunit alone, a protective footprint encompassing the region between residue positions -41 ...	1989	2523702
phage genetic sites involved in lambda growth inhibition by the escherichia coli rap mutant.	the rap mutation of escherichia coli prevents the growth of bacteriophage lambda. we have isolated phage mutants that compensate for the host deficiency. the mutations, named bar, were genetically located to three different loci of the lambda genome: bari in the attp site, barii in the ciii ea10 region, and bariii within or very near the imm434 region. the level of lambda leftward transcription correlates with rap exclusion. phage lambda mutants partially defective in the pl promoter or in pl-tr ...	1989	2523838
integration of mini-retroviral dna: a cell-free reaction for biochemical analysis of retroviral integration.	after retroviral infection of a permissive cell, the viral rna is reverse-transcribed to make a dna copy of the viral genome. integration of this dna copy into the host genome is a necessary step for efficient viral replication. we have developed a cell-free system for integration of exogenous mini-retroviral dna. the termini of this linear mini-moloney murine leukemia virus (momlv) dna are designed to mimic the ends of authentic unintegrated momlv dna. the viral proteins required for integratio ...	1989	2524066
nucleotide sequence of the stp-1 gene coding for rat spermatid nuclear transition protein 1 (tp1): homology with protamine p1 and assignment of the mouse stp-1 gene to chromosome 1.	spermatid transition protein 1 (tp1) is a 54 amino acid (aa), highly basic chromosomal protein found in mammals during the brief period when histones are being replaced by protamines in the haploid phase of spermatogenesis. using a cdna clone as probe, we have isolated the gene (stp-1) coding for rat tp1 from a population of recombinant bacteriophage lambda. the nucleotide (nt) sequence was established from a point 126 nt upstream from the mrna cap site to a point about 30 nt downstream from the ...	1989	2524424
ordered assembly of nucleoprotein structures at the bacteriophage lambda replication origin during the initiation of dna replication.	replication of the chromosome of bacteriophage lambda depends on the cooperative action of two phage-coded proteins and seven replication and heat shock proteins from its escherichia coli host. as previously described, the first stage in this process is the binding of multiple copies of the lambda o initiator to the lambda replication origin (ori lambda) to form the nucleosomelike o-some. the o-some serves to localize subsequent protein-protein and protein-dna interactions involved in the initia ...	1989	2525129
specialized nucleoprotein structures at the origin of replication of bacteriophage lambda. protein association and disassociation reactions responsible for localized initiation of replication.	binding of the o protein of phage lambda to the replication origin (ori lambda) results in the formation of an organized nucleoprotein structure termed the o-some. the o-some serves to localize and initiate a six-protein sequential reaction that provides for localized unwinding of the origin region, the critical prepriming step for precise initiation of dna replication. by the use of electron microscopy of gold-tagged antibody complexes, we have defined four stages of protein association and dis ...	1989	2525130
modulation of the sos response by truncated reca proteins.	reca protein plays several key roles in the sos response. we have constructed truncated proteins and examined their capacity to accomplish weigle reactivation and mutagenesis of bacteriophage lambda and recombination in escherichia coli. our data indicate that the 17 carboxyl terminal amino acids are not essential to reca function. however in the presence of wild-type reca protein, the truncated protein reduces the efficiency of recombination without affecting either mutagenesis or induction of ...	1989	2525224
transcription of a region downstream from lambda ori is required for replication of plasmids derived from coliphage lambda.	dna replication of lambda phage depends on transcriptional activation at or around the lambda ori region by rna polymerase. to elucidate the function of the transcriptional activation, we constructed several plasmids carrying lambda ori and lacp, whose relative locations and directions were different from each other, and studied replication activity of these recombinant plasmids. transcription in a region immediately downstream from lambda ori, but not in the lambda ori region, was found to be e ...	1989	2525225
flanking dna-sequences contribute to the specific binding of ci-repressor and or1.	the binding of ci-repressor to a series of mutant operators containing or1 of the right operator of bacteriophage lambda was investigated. sites or2 and/or or3 were inactivated by either point or deletion mutations. the free energy of binding repressor to or1 in the wildtype operator, delta g1, is -13.7 +/- 0.3 kcal/mol. delta g1 determined for an or2- operator created by a single point mutation in or2 is -13.6 +/- 0.2 kcal/mol. in contrast, delta g1 for the binding of repressor to a cloned synt ...	1989	2525252
[features of expression of cloned genes under the control of tandem promotors pl and pr of phage lambda].	the regulatory block p'r from the bacteriophage lambda has been inserted between the promoter and initial part of the gene into the plasmid pcj55 carrying the gene for the klenow fragment under the control of pl. as it should be predicted, at the inverted orientation the sharp decrease in the klenow fragment quantity is registered. however, at the direct orientation there is some decrease in the synthesis of the protein, as compared with the synthesis of the klenow fragment in the strain harbour ...	1989	2525666
[the z-form of bacteriophage lambda dna, modified in situ].	using the methods of chemical modification, restriction analysis and immune-electron microscopy it has been shown that the definite regions of the bacteriophage lambda dna contain unpaired bases in situ. the distribution map of such sites along the genome has been constructed. the correlation of the in situ modification and the reaction with anti-z-dna antibodies is shown for the 44972 bp site of bacteriophage dna. the possibility of the existence of z-form dna in situ is discussed.	1989	2525667
large scale preparation of bacteriophage lambda by tangential flow ultrafiltration for isolation of lambda dna.	a preparative procedure for purifying bacteriophage lambda from large volumes of phage lysates by recirculating tangential flow ultrafiltration is described. lambda dna, isolated by deproteinization of the phage, is suitable for use in molecular biology.	1989	2525883
thermodynamic and enzymological characterization of the interaction between transcription termination factor rho and lambda cro mrna.	termination of transcription at tr1, the rho-dependent terminator between genes cro and cii of bacteriophage lambda, is mediated by interactions between rho protein and an rna sequence element called rut. we show, using a filter retention assay technique, that rho protein binds with about 10-fold lower affinity to variants of cro rna lacking both parts of rut or to normal cro rna having one or the other part of rut bound to a complementary dna oligonucleotide than it binds to unmodified cro rna. ...	1989	2525925
a general method for detecting rearrangements in a bacterial genome.	an effective method was developed to monitor genome rearrangement in bacteria. the whole procedure consists of five steps. (i) genomic dnas of reference cells and test cells are digested with the same restriction enzyme. (ii) the dna restriction fragments from the test cells are radioactively labeled. (iii) the labeled dna fragments of test cells are mixed with unlabeled dna fragments from reference cells that are 100- to 1000-fold in excess and the mixture is electrophoresed in an agarose gel. ...	1989	2526339
characterization, overproduction and purification of the product of gene 1 of bacillus subtilis phage phi 29.	unit-length phi 29 dna was not synthesized after restrictive infection of bacillus subtilis with the phi 29 mutant sus1(629) indicating that the phage phi 29 protein p1 is needed for the viral dna replication. sequencing of the orf-6 of mutant sus1(629) showed that a c in the wild-type (wt) phage had been changed to a t at nt position 19 of the orf-6, giving rise to a taa ochre codon, indicating that this orf corresponds to gene 1. orf-6 was cloned in plasmid pplc28 under the control of the pl p ...	1989	2526779
a component of the side tail fiber of escherichia coli bacteriophage lambda can functionally replace the receptor-recognizing part of a long tail fiber protein of the unrelated bacteriophage t4.	the distal part of the long tail fiber of escherichia coli bacteriophage t4 consists of a dimer of protein 37. dimerization requires the catalytic action of protein 38, which is encoded by t4 and is not present in the virion. it had previously been shown that gene tfa of the otherwise entirely unrelated phage lambda can functionally replace gene 38. open reading frame (orf) 314, which encodes a protein that exhibits homology to a cooh-terminal area of protein 37, is located immediately upstream ...	1989	2526805
identification of a functional allele of a human interferon-alpha gene previously characterized as a pseudogene.	three recombinant phage lambda l47 clones containing 4 alpha interferon (ifn) genes have been isolated from a newly constructed human genomic library. each gene is an allele of a previously described ifn gene, three being only minor variants. the fourth gene smtiii.1a is a functional allele of the psi leif-l gene which previously has been described only as a pseudogene. therefore, it appears likely that other variant alleles may remain to be described and that the ifn system may be able to toler ...	1989	2526839
cystathionase: high-performance liquid chromatography. molecular cloning in lambda gt11. nonradioactive immunodetection of fusion protein.	a method of purification of rat liver cystathionase by high-performance liquid chromatography (hplc) utilizing non-ideal gel filtration method is proposed. resolution factors-flow rate, ph values, ionic strength of the mobile phase-were optimized. antibodies to the enzyme were purified using an immunosorbent synthesized on the basis of epoxylated toyopearl-65. radioimmunoassay and immunoblotting demonstrated antibody monospecificity towards cystathionase. these monospecific antibodies were utili ...	1989	2527065
the effect of attachment site mutations on strand exchange in bacteriophage lambda site-specific recombination.	recombination of phage lambda attachment sites occurs by sequential exchange of the dna strands at two specific locations. the first exchange produces a holliday structure, and the second resolves it to recombinant products. heterology for base substitution mutations in the region between the two strand exchange points (the overlap region) reduces recombination; some mutations inhibit the accumulation of holliday structures, others inhibit their resolution to recombinant products. to see if hete ...	1989	2527180
[expression of the bacillus pumilus chloramphenicol acetyltransferase gene in bacillus subtilis, achieved by the p-r-promotor of phage lambda].	the possibility of expression of the bacillus pumilus chloramphenicol acetyltransferase gene (cat) in bacillus subtilis from the pr promoter of phage lambda has been investigated in this work. for this purpose, the plasmid ppl703 carrying the b. pumilus dna segment with the cat gene lacking promoter has been combined with the plasmid pbm21 containing the pr promoter. the recombinant plasmid pel1 is capable of providing the 60 mkg/ml chloramphenicol resistance in bac. subtilis cells.	1989	2527182
effects of all single base substitutions in the loop of boxb on antitermination of transcription by bacteriophage lambda's n protein.	the 'n' antitermination proteins of lambdoid bacteriophages are essential for overcoming multiple transcription terminators located within the major early operons of these phages (1). in order for n proteins to function, a genome sequence specifying n utilization, nut, must be located within an operon, between the promoter and the terminators (2). two components have been identified within nut: 8-base boxa, conserved among different phages and implicated in the recognition of host nusa protein, ...	1989	2527353
mutations of the phage lambda attachment site alter the directionality of resolution of holliday structures.	integrative recombination of bacteriophage lambda occurs by two sequential, reciprocal strand exchanges at specific positions within the attachment sites. both exchanges are promoted by the lambda int protein; the first forms a holliday structure, and the second resolves it to recombinant products. recombination requires sequence homology within the 7 bp 'overlap' region that separates the two points of strand exchange. to see if homology promotes the second strand exchange, we constructed attac ...	1989	2527743
initiation of lambda dna replication with purified host- and bacteriophage-encoded proteins: the role of the dnak, dnaj and grpe heat shock proteins.	based on previous in vivo genetic analysis of bacteriophage lambda growth, we have developed two in vitro lambda dna replication systems composed entirely of purified proteins. one is termed 'grpe-independent' and consists of supercoiled lambda dv plasmid dna, the lambda o and lambda p proteins, as well as the escherichia coli dnak, dnaj, dnab, dnag, ssb, dna gyrase and dna polymerase iii holoenzyme proteins. the second system includes the e.coli grpe protein and is termed 'grpe-dependent'. both ...	1989	2527744
expression vector with two-step control by the ci-pr-q-p'r-qut-t'r module of coliphage lambda.	a plasmid expression vector (pceq3), using temperature-regulated transcription from the p'r promoter of bacteriophage lambda, has been constructed. the vector is derived from pbr327 in which the ecori-clai fragment of plasmid dna is replaced with a 2.2-kb dna module ci857-pr-q-p'r-qut-t'r, consisting of two regions of the lambda genome. the first region contains the repressor gene ci857 and promoter pr; the second one contains gene q and the late promoter p'r. when the repressor protein, product ...	1989	2527778
high level expression of genes cloned in phage lambda gt11.	plasmid cloning vectors have been constructed which allow genes originally cloned in lambda gt11 to be expressed at a high level in escherichia coli. they are based on the pembl and puc vectors, with the genes transcribed from the lac promoter. the ecori site in the vector has been altered to be in the same reading frame as the site used for cloning in lambda gt11. cloned proteins are expressed fused to a 2-kda leader sequence containing a run of six aparagine residues which considerably improve ...	1989	2527780
translesion synthesis is the main component of sos repair in bacteriophage lambda dna.	agents that interfere with dna replication in escherichia coli induce physiological adaptations that increase the probability of survival after dna damage and the frequency of mutants among the survivors (the sos response). such agents also increase the survival rate and mutation frequency of irradiated bacteriophage after infection of treated bacteria, a phenomenon known as weigle reactivation. in uv-irradiated single-stranded dna phage, weigle reactivation is thought to occur via induced, erro ...	1989	2527845
an oligonucleotide probe specific for onchocerca volvulus.	a genomic dna library of a liberian strain of onchocerca volvulus was prepared in the vector bacteriophage lambda gt10. the library was differentially screened by hybridisation with radiolabelled total dna from the homologous parasite, two heterologous onchocerca parasites (onchocerca gibsoni and onchocerca gutturosa) and human liver cells. a clone (c1a1) was isolated whose binding to o. volvulus dna was at least 50 times stronger than to the other parasite dna samples. no binding was observed w ...	1989	2528065
a systematic study of field inversion gel electrophoresis.	the mobilities of oligomers of phage lambda dna and of yeast chromosomes in agarose gels during field inversion gel electrophoresis (fige) were measured at different pulse times and electric fields. also the ratios between forward and backward pulse times and/or field gradients were varied. the problem of 'band inversion' during fige, leading to an ambiguity in the mobility of large dna fragments, was solved by using two dimensional gel electrophoresis with different parameters in the first and ...	1989	2528121
functional replacement of a protein-induced bend in a dna recombination site.	in recent years the capacity of proteins to bend dna by binding to specific sites has become a widely appreciated phenomenon. in many cases, the protein-dna interaction is known to be functionally significant because destruction of the dna site or the protein itself results in an altered phenotype. an important question to be answered in these cases is whether bending of dna is important per se or is merely a consequence of the way a particular protein binds to dna. here we report direct evidenc ...	1989	2528697
phasing of protein-induced dna bends in a recombination complex.	many of the structures responsible for replication, transcription initiation and recombination arise from complex sets of protein-protein interactions and the folding of dna in three dimensions, with protein-induced bending of dna often playing an integral role. the magnitude and orientation of dna bending induced by various single proteins has been estimated by gel mobility shift methods and by modelling of crystallographic data. the site-specific recombination by which bacteriophage lambda (ph ...	1989	2528698
half-att site substrates reveal the homology independence and minimal protein requirements for productive synapsis in lambda excisive recombination.	the early events in site-specific excisive recombination were studied with phage lambda half-att sites that have no dna to one side of the strand exchange region; they carry a single core-type integrase binding site and either p or p' arm flanking dna. these half-attr and half-attl sites exhibit normal properties for the initial (covalent) top-strand transfer and form stable intermediates independent of later steps in the reaction. with these novel substrates we show that xis specifically promot ...	1989	2529039