Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “host range”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 649 records · Page 36Linked to original sources
PubMed1983

Construction of a broad-host-range kanamycin-resistant plasmid vector.

A new 10.2-kb plasmid, pIRL2, was constructed by using a 2140-bp DNA fragment carrying the Kmr gene and BamHI cohesive ends. These BamHI cohesive ends were used to trap the replicating DNA fragment from a partial Sau3A digest of the plasmid R300B. The plasmid contains unique EcoRI, SstI, HindIII, SmaI, SalI, and XhoI sites. These sites can be used as cloning sites without the loss of Kmr. A unique BglII site can be used as a cloning site by insertional inactivation of the Kmr structural gene, coding for neomycin phosphotransferase type II. The new plasmid carries the Sur and Smr genes of R300B. The direction of transcription from the neo promoter is clockwise, the same as that from the sul promoter. The plasmid retains the broad-host-range function of R300B, and thus it may be used for gene cloning in Rhizobium and Agrobacterium for genetic engineering of plant cells.

Cloning, Molecular↗
PubMed1993

Sequence diversity in the surface-exposed amino-terminal region of the coat proteins of seven strains of sugarcane mosaic virus correlates with their host range.

The N-terminal region of the coat proteins of five strains (Isis, Brisbane, Sabi, Bundaberg, and BC) of sugarcane mosaic virus (SCMV) isolated from four different plant species (sugarcane, sabi grass, wild sorghum, and blue couch grass) have been compared with the previously published data for SCMV-SC and SCMV-MDB, isolated from sugarcane and maize, respectively. The region, beginning at residue 11 and ending 16 residues beyond the second trypsin cleavage site of the coat protein, varied in size from 68 amino acid residues (Bundaberg) to 115 residues (BC) and contained repeat sequence motifs. Comparisons of the sequence identity and the nature of the repeats in the seven sequences showed that there were five different sequence patterns. These could be grouped further into three subsets which appeared to correlate with the host range of the strains. SCMV-Brisbane, SC, and Isis, isolated from sugarcane, showed almost identical sequence patterns and formed one subset. The other four strains had different sequence patterns and could be grouped further into a Sabi and Bundaberg subset (isolated from sabi grass), and a BC and MDB subset.

Amino Acid Sequence↗
PubMed1996

Broad host range of human T-cell leukemia virus type 1 demonstrated with an improved pseudotyping system.

Studies of human T-cell leukemia virus type 1 (HTLV-1) have been hampered by the difficulty of achieving high cell-free and cell-associated infectious titers. Current retroviral pseudotyping systems using the HTLV-1 envelope generate titers of less than 200 infectious particles per ml. We describe here an improved system for pseudotyping using a defective human immunodeficiency virus (HIV) type 1 genome in combination with HTLV-1 env in 293T producer cells. Introduction of additional copies of rev and treatment of cells with sodium butyrate resulted in a cell-associated titer of 10(5)/ml and cell-free titers of greater than 10(4)/ml . By using this system, we found that the host range of HTLV-1 is even greater than previously suspected. Earlier studies which assigned a chromosomal location for the HTLV-1 receptor may therefore reflect cell-to-cell variation in receptor number rather than the absolute presence or absence of a receptor. The generation of higher-titer HIV(HTLV-1) may facilitate identification of the cellular receptor and investigations of the pathophysiology of HTLV-1 infection.

Cell Line↗
PubMed2003

Porites ulcerative white spot disease: description, prevalence, and host range of a new coral disease affecting Indo-Pacific reefs.

The results of an investigation of a new coral disease affecting Indo-Pacific reefs are presented. Porites ulcerative white spot disease (PUWS) is characterized by discrete, bleached, round foci, 3 to 5 mm in diameter, that may either regress or progress to full tissue-thickness ulcerations that coalesce, occasionally resulting in colony mortality. Monitoring of 25 diseased and 5 healthy reference colonies for 17 mo revealed that advanced stages of the disease were characterized by lesion coalescence, partial colony death (i.e. portions of the colony still alive; n = 17) and total colony death (n = 2). Field transmission experiments revealed that 95% of healthy colonies developed lesions within 5 wk after continual exposure to diseased branches, while 60% of the reference colonies remained healthy. The host range of PUWS includes branching and massive Porites spp., and prevalence per species was positively correlated with species density. On 10 reefs surveyed in the Central Philippines, 22 +/- 7% (mean +/- SE) of poritid colonies were infected, and the disease was present on 80% of the surveyed reefs. Poritids are dominant Indo-Pacific reef builders; a disease targeting this genus could cause major shifts in community structure over time. This report contributes to the limited knowledge of PUWS impacts in this region.

Animals↗
PubMed1977

Host range characteristics of the primate coccidian, Isospora arctopitheci Rodhain 1933 (Protozoa: Eimeriidae).

Studies were conducted on 35 primates, 12 carnivores, and 2 marsupials to determine their susceptibility to the primate coccidian, Isospora arctopitheci. Patent oocyst infections resulted in 12 of the 14 species of animals investigated. These included 6 genera of New World primates native to Panama: Saguinus geoffroyi, Aotus trivirgatus, Ateles fusciceps, Cebus capucinus, Alouatta villosa, and Saimiri sciureus. In addition 4 families of carnivores (2 domestic and 2 sylvatic) and 1 species of marsupial became infected following experimental exposure. These animals are represented respectively by the following 6 genera and species: Canis familiaris; Felis catus; Nasua nasua, and Potos flavus; Eiria barbara; and Didelphis marsupialis. Four Old World rhesus monkeys, Macaca mulatta, and 1 carnivore, Bassaricyon gabbii, did not become oocyst positive. This unusually large host range makes this isosporan unique among the coccidia that have been investigated to date.

Alouatta↗
PubMed1985

Construction of recombinants between molecular clones of murine retrovirus MCF 247 and Akv: determinant of an in vitro host range property that maps in the long terminal repeat.

The leukemogenic mink cell focus-forming (MCF) retroviruses such as MCF 247 have biological properties distinct from those of their ecotropic progenitors. Nucleotide sequences encoding portions of gp70, Prp15E, and the long terminal repeat differ between the two types of viruses. To investigate the role of each of these genetic elements in determining the biological properties of MCF viruses, we prepared infectious molecular clones of MCF 247 and generated a set of recombinants between these clones and a molecular clone of Akv, the ecotropic parent of MCF 247. Each molecular clone of MCF 247 was distinct. All the recombinants between Akv and MCF 247 yielded infectious virus upon transfection. Most interestingly, recombinants which contain the long terminal repeat of MCF 247 were found to have an in vitro host range property that has been correlated with high oncogenic activity and thymotropism of certain MCF isolates; namely, they plated with higher efficiency on SC-1 cells than on NFS mouse embryo cells. Nononcogenic MCF isolates showed a slight preference for NFS cells, whereas Akv virus plated with approximately equal efficiency on the two cell types.

Animals↗
PubMed2001

Sudden increase in Pseudomonas aeruginosa nosocomial strains with broad host range transfer of antibiotic resistance.

We investigated transfer of antibiotic resistance from 51 multiply resistant strains of Pseudomonas aeruginosa isolated from seriously ill patients in the Frankfurt University Clinics. Nine isolates directly transferred resistance to three recipient strains used. Ticarcillin and cephalothin resistance determinants were accepted from eight isolates, and in one case a kanamycin resistance determinant was transferred. The total spectrum of resistance transferred demonstrated that several donor strains transferred a different set of resistance determinants to all three recipient strains. Two P. aeruginosa isolates transferred spectrum of seven resistance determinants including ceftazidime, cefepime and aztreonam, three isolates transferred five determinants and four isolates transferred four resistance determinants. The fact that identical spectra of multiple drug resistance were transferred to recipient strains belonging to three different species (Escherichia coli, Proteus mirabilis and P. aeruginosa), indicates a broad host range in all three transferable genetic elements not observed in previous transfers from P. aeruginosa strains.

Conjugation, Genetic↗
PubMed2001

Construction and use of a broad-host-range plasmid expressing the lamB gene for utilization of bacteriophage lambda vectors in the marine bacterium Vibrio harveyi.

The remarkable success of Escherichia coli as a model organism in molecular genetics was dependent, among other things, on its susceptibility to genetic manipulation. Many versatile and sophisticated genetic tools for molecular biology studies are derived from bacteriophage lambda. However, this bacteriophage is specific for E. coli, and thus lambda-based techniques have been restricted to this bacterium. Plasmids expressing the E. coli gene coding for bacteriophage lambda receptor were reported previously, and introduction of such plasmids into cells of some other bacteria made them sensitive to phage lambda infection. However, we found that these systems were not efficient for Vibrio harveyi, one of the most frequently investigated species of marine bacteria. Here we describe construction of a broad-host-range plasmid expressing the lamB gene. Introduction of this plasmid to V. harveyi cells and expression of lamB made this strain susceptible to bacteriophage lambda adsorption and lambda DNA injection. Foreign genetic material could be introduced into cells of this strain using a cosmid vector.

Journal Article↗
PubMed1986

Characterization and recombination mapping of an antigenic and host range mutation of canine parvovirus.

A mutant of canine parvovirus (CPV) was derived after culture of a highly passaged isolate of CPV in the NLFK feline cell line. The virus (CPV-102/10) differed from the parental strain in its antigenic type when tested with a panel of neutralizing monoclonal antibodies, and in its relative ability to replicate in a dog cell line or in dogs. The mutant formed little replicative form DNA in the canine cells. Five single recombinants and two double recombinants between CPV-102/10 and a wild type CPV were constructed by digesting purified viral replicative form DNA with restriction enzymes, ligating the separated ends from the different strains, and examining the viruses isolated after transfecting the DNA into cell cultures. Analysis of the recombinant viruses showed that the mutation(s) determining both the antigenic and host range differences mapped between 64 and 73 map units in the genome, within the capsid protein gene. Sequencing the DNA from that region revealed differences of two adjacent amino acids, both resulting in nonconservative differences in the predicted amino acid sequences of the viruses. These results show that the ability of CPV to infect dogs or their cultured cells is determined, at least in part, by the conformation of the surface of the virus capsid.

Amino Acid Sequence↗
PubMed1986

T-even type phages can change their host range by recombination with gene 34 (tail fibre) or gene 23 (head).

T-even type phages recognize their cellular receptors with the tip of their long tail fibres. The gene products involved in receptor recognition are proteins 37 and 38. While screening libraries of phage K3 with a probe of gene 38 from phage T2, a class of weakly hybridizing clones was found in addition to the expected clones of gene 38 of K3. One of these clones was identified as being from gene 23 of the phage which codes for the major head subunit; another clone originated from gene 34, which codes for the proximal half of the long tail fibres. Neither gene product 23 nor 34 is involved in receptor recognition. Phages can recombine with the DNA of the gene 23 and gene 34 clones and change the host range.

Base Sequence↗
PubMed2005

Plasmid donor affects host range of promiscuous IncP-1beta plasmid pB10 in an activated-sludge microbial community.

Horizontal transfer of multiresistance plasmids in the environment contributes to the growing problem of drug-resistant pathogens. Even though the plasmid host cell is the primary environment in which the plasmid functions, possible effects of the plasmid donor on the range of bacteria to which plasmids spread in microbial communities have not been investigated. In this study we show that the host range of a broad-host-range plasmid within an activated-sludge microbial community was influenced by the donor strain and that various mating conditions and isolation strategies increased the diversity of transconjugants detected. To detect transconjugants, the plasmid pB10 was marked with lacp-rfp, while rfp expression was repressed in the donors by chromosomal lacI(q). The phylogeny of 306 transconjugants obtained was determined by analysis of partial 16S rRNA gene sequences. The transconjugants belonged to 15 genera of the alpha- and gamma-Proteobacteria. The phylogenetic diversity of transconjugants obtained in separate matings with donors Pseudomonas putida SM1443, Ralstonia eutropha JMP228, and Sinorhizobium meliloti RM1021 was significantly different. For example, the transconjugants obtained after matings in sludge with S. meliloti RM1021 included eight genera that were not represented among the transconjugants obtained with the other two donors. Our results indicate that the spectrum of hosts to which a promiscuous plasmid transfers in a microbial community can be strongly influenced by the donor from which it transfers.

Conjugation, Genetic↗
PubMed1988

Broad-host-range plasmid and M13 bacteriophage-derived vectors for promoter analysis in Escherichia coli and Pseudomonas aeruginosa.

A set of bacteriophage and plasmid vectors containing xylE as a reporter gene was constructed for the analysis of promoters functional in Escherichia coli and in other Gram-negative bacteria. Two M13 bacteriophage derivatives, M13mVDX18 and M13mMK010, were designed for rapid cloning, screening and sequencing of DNA fragments promoting transcription in E. coli. To demonstrate their utility, total cellular DNA from a variety of bacterial species including Pseudomonas aeruginosa strain PAO was shotgun cloned in M13 vectors and clones displaying promoter activity in E. coli were isolated. These randomly cloned promoters from P. aeruginosa, Borrelia burgdorferi, Streptococcus pneumoniae and other bacterial species were sequenced without a need for further subcloning manipulation. The promoter activity of P. aeruginosa clones was verified by subcloning inserts on a broad-host-range promoter probe vector pVDX18 and assaying the xylE transcription from these promoters in P. aeruginosa. The pVDX18 vector was also used for initial characterization of the algD promoter controlling mucoidy in P. aeruginosa. The activities of the wild-type and deletion clones of the algD promoter were compared. Results indicated that the region containing direct and inverted repeats at -55 to -110 bp upstream of the mRNA 5' end was important for the activation of the algD transcription in mucoid P. aeruginosa infecting cystic fibrosis patients.

Bacteriophages↗
PubMed1992

Coexpression of the simian immunodeficiency virus Env and Rev proteins by a recombinant human adenovirus host range mutant.

Recombinant human adenoviruses (Ads) that replicate in the intestinal tract offer a novel, yet practical, means of immunoprophylaxis against a wide variety of viral and bacterial pathogens. For some infectious agents such as human immunodeficiency virus (HIV), the potential for residual infectious material in vaccine preparations must be eliminated. Therefore, recombinant human Ads that express noninfectious HIV or other microbial proteins are attractive vaccine candidates. To test such an approach for HIV, we chose an experimental model of AIDS based on simian immunodeficiency virus (SIV) infection of macaques. Our data demonstrate that the SIV Env gene products are expressed in cultured cells after infection with a recombinant Ad containing both SIV env and rev genes. An E3 deletion vector derived from a mutant of human Ad serotype 5 that efficiently replicates in both human and monkey cells was used to bypass the usual host range restriction of Ad infection. In addition, we show that the SIV rev gene is properly spliced from a single SIV subgenomic DNA fragment and that the Rev protein is expressed in recombinant Ad-SIV-infected human as well as monkey cells. The expression of SIV gene products in suitable live Ad vectors provides an excellent system for studying the regulation of SIV gene expression in cultured cells and evaluating the immunogenicity and protective efficacy of SIV proteins in macaques.

Adenoviridae↗
PubMed1996

Evolution of canine parvovirus involved loss and gain of feline host range.

Canine parvovirus (CPV) type-2 emerged as a new virus infecting dogs in 1978, and it was probably derived as a variant of feline panleukopenia virus or of a closely related virus infecting another carnivore. CPV type-2 was subsequently replaced in nature by antigenically variant viruses (CPV type-2a and CPV type-2b) which now coexist in dog populations worldwide. We show that CPV type-2 isolates did not replicate in cats, but that both CPV type-2a and CPV type-2b isolates replicated efficiently. About 10% of the viruses isolated from cats with natural parvovirus disease were antigenically indistinguishable from CPV type-2a or type-2b. The capsid protein gene sequence of a 1990 feline parvovirus isolate ("FPV-24") was essentially identical to the sequence of CPV type-2b viruses from dogs. The loss and reacquisition of the feline host range in CPV was most likely due in each case to small numbers of changes in a region of the virus capsid where three protein monomers interact.

Animals↗
PubMed1986

Narrow host range of AIDS-related retroviruses (YU-1, 2, 3, 4) isolated from Japanese hemophiliacs: inability to infect H9, Molt-4, and MT-4 cells.

Infectivity was assayed by infecting human T-lymphocytes, H9, Molt-4, and MT-4 cells with different strains of AIDS viruses (HTLV-III, LAV, ARV, and YU viruses). Human T-lymphotropic virus type-III (HTLV-III), lymphadenopathy-associated virus (LAV), and AIDS-associated retrovirus (ARV) were able to infect all kinds of target cells tested and to induce virus-specific antigens, whereas Japanese isolates, YU viruses, infected only interleukin-2-dependent human T-lymphocytes. Long-term propagation of the YU viruses and pretreatment of the cells with Polybrene did not allow the YU virus to produce viral antigens by infecting H9, Molt-4, and MT-4 cells. Thus, YU viruses have a rather narrow host range as compared with HTLV-III, LAV, and ARV. These different infectivities may be reflected in the progress and symptoms of AIDS in vivo.

Acquired Immunodeficiency Syndrome↗
PubMed1981

In vitro host range of equine infectious anemia virus.

Equine infectious anemia virus (EIAV) was successfully inoculated onto cell cultures of canine and feline origin, resulting in chronic infections in these cultures. Infection of equine cell cultures, which were the previous sole in vitro source demonstrated for virus production, was also performed for comparative purposes. Determination of the nature of the virus produced in the heterologous as well as the equine cells was accomplished in several ways. SDS-PAGE of purified virus from the different cell lines indicated very similar protein composition. Immunological identity was observed in gel diffusion tests employing an antiserum to the major core protein (p24) of equine-derived EIAV. Competition radioimmunoassays also indicated similar antigenicity in the viruses derived from the several cell lines. Strong relatedness was further demonstrated by hybridization of viral RNAs to EIAV complementary DNA. These data indicate that EIAV has an amphotropic cell culture host range and that the viruses isolated from the permissive lines were similar.

Animals↗
PubMed1994

Pseudotyped REV/SRV retroviruses reveal restrictions to infection and host range within members of the same receptor interference group.

The reticuloendotheliosis virus (REV) group of retroviruses and type D simian retroviruses (SRV) belong to the same receptor interference group. The cellular receptor for these viruses has not yet been identified. In order to study the distribution of the receptor and to identify a receptor negative cell line, vector viral pseudotypes between REV and SRV were made. Using these viral pseudotypes, susceptibility to infection was examined in some rodent and marsupial cell lines. Infectivity assays with these envelope pseudotypes demonstrated that all cell types tested were resistant to infection. However, treatment of the rodent cells with the N-linked glycosylation inhibitor tunicamycin rendered most of the cells susceptible to infection. These results indicate that all the rodent cells tested express a nonfunctional receptor for viruses of the REV and SRV groups, which can be made functional by tunicamycin treatment. A difference in receptor host range among members of the same receptor interference group was observed which suggests that the REV/SRV receptor for this interference group might be differentially modified in different cell types. The studies also identified at least one cell line not expressing the REV/SRV receptor which should be useful for isolating the gene encoding the receptor.

Animals↗
PubMed1987

An adenovirus type 3 host range variant with mutations in the E1a and E3 early gene regions.

A spontaneous variant of adenovirus (Ad) type 3 (subgroup B) was identified, which did not grow in HeLa cells, but grew in 293 cells with a large plaque morphology. The variant (Ad3var100) had a defect in the the early gene region E1a; it could grow in cells that supplied E1a functions and was complemented for growth in HeLa cells by Ad5 wild-type (subgroup C) but not by the E1a deletion mutant Ad5d1312. It also bore a deletion of some 1.5 kb in the E3 region. The loss of these sequences conferred on the variant the ability to inhibit Ad5 wild-type virus, although Ad3 wild-type was dominant over the variant. No transdominance was seen between wild-type Ad3 and Ad5. The E1a mutation was placed in a wild-type background and this E1a mutant had the host range properties of the variant, but did not retain the large plaque morphology and was not dominant over Ad5. The E3 mutation was separated from the E1a lesion by marker rescue; the resulting E3 mutant retained dominance over Ad5, grew in HeLa cells and had a plaque morphology intermediate between wild-type and variant.

Adenovirus Early Proteins↗