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PubMed1986

Production and purification of eta (ETA) precipitinogen, species-specific to mycobacterium tuberculosis and its intradermal reactivity.

The partially purified preparation of eta precipitinogen which is species-specific for Mycobacterium tuberculosis showed skin reaction specificity for guinea pigs sensitized with M. tuberculosis. Strains of M. tuberculosis and the conditions for cultivation for optimal production of stable eta precipitinogen preparation in a large scale were investigated. Additional purification of procedures of the partially purified preparation of eta were also investigated. The significance of eta precipitinogen in the diagnosis of mycobacterial infection is discussed.

Animals↗
PubMed1978

Development of species identification in ducklings: IV. Change in species-specific perception caused by auditory deprivation.

The purpose of the present experiments was to identify the change in species-specific perception that underlies the aurally deprived ducklings' lack pf preference or discrimination in the mallard versus chicken call test. Among other acoustic differences, the mallard and chicken maternal calls differ in repetition rate (3.7 and 2.3 notes/sec, respectively). The present experiments showed the dimension of repetition rate to be uppermost in the perceptual hierarchy underlying the auditory aspect of species identification in Peking ducklings. The relatively narrow species-typical repetition-rate preferences of normal Peking ducklings (about 4--6 notes/sec) is lacking in the aurally deprived ducklings, and they respond to lower rates than usual (2.3 notes/sec). This broadening of the range of responsiveness on a perceptual dimension (repetition rate) that is basic to species identification accounts for the devocal ducklings' lack of discrimination in the mallard versus chicken call test.

Age Factors↗
PubMed1993

Mapping human T cell epitopes in leishmania gp63. Identification of cross-reactive and species-specific epitopes.

Both a conserved surface metalloprotease of leishmania, gp63 as well as certain gp63-derived peptides, have been shown to have immunoprophylactic potential in mouse models of leishmaniasis. In addition, PBMC from individuals with cutaneous, mucosal, or cured visceral leishmaniasis respond in vitro to both native and rgp63. In this report, we mapped human T cell epitopes within gp63. T cells from leishmaniasis patients responded in vitro to certain peptides of gp63 by proliferation and IFN-gamma production. One peptide, (PT7), stimulated cells from all individuals tested (n = 7). Anti-PT7 T cell lines derived from PBMC of a mucosal leishmaniasis patient contained a heterogeneous population of cells which responded by proliferation and IFN-gamma production to in vitro stimulation with Leishmania promastigote lysate. Another peptide (PT1) derived from Leishmania chagasi gp63 stimulated PBMC from an L. chagasi patient although the corresponding Leishmania major-derived peptide did not. Both L. major PT7 and L. chagasi PT1 were able to induce anti-Leishmania-specific T cell lines from normal human PBMC. These T cell lines responded to in vitro stimulation with promastigote lysate indicating that both peptides were immunogenic for naive T cells in vitro. In conclusion, both antigenic and immunogenic gp63 peptide sequences have been defined, some appearing to be conserved among Leishmania species and at least one that appears to be species specific.

Amino Acid Sequence↗
PubMed1990

Species-specific substrate interaction of picornavirus 3C proteinase suballelic exchange mutants.

The substrate recognition properties of the polio-virus type 1 and coxsackievirus B3 3C proteinases have been examined in vitro by allelic and suballelic exchange of 3C between the cloned virus genomes. The activity of the altered 3C proteinases was examined by translation of synthetic RNA in a rabbit reticulocyte lysate/HeLa cell extract translation system. Analysis of the subsequent processing of virus polyproteins by the altered 3C proteinases showed that all of the mutant proteinases maintained some catalytic activity. The disruption of polyprotein cleavages mediated by 3C followed a distinct pattern, suggesting a specific order of events in processing the polyprotein. Differences in cleavage activity of mutant proteinases when tested on coxsackievirus or poliovirus protein substrates suggest that, although structural elements throughout the proteinase play a role in efficient substrate utilization, the carboxyl-terminal region of the 3C proteinase contains elements most important in species-specific substrate recognition.

Alleles↗
PubMed2006

Tissue-cell- and species-specific expression of gonadotropin-regulated long chain acyl-CoA synthetase (GR-LACS) in gonads, adrenal and brain. Identification of novel forms in the brain.

Gonadotropin-regulated long chain acyl-CoA synthetase (GR-LACS) is a novel hormonally regulated fatty acyl-CoA synthetase (FACS) with activity for long-chain fatty acids. The presence of this enzyme in the Leydig cells of the mature rat testis and its mode of regulation suggest that it participates in testicular steroidogenesis. This study demonstrates that GR-LACS expression is tissue, cell and species-specific. The 79 kDa GR-LACS protein is expressed in rodent gonads and brain, and only in the mouse in the adrenal cortex. In the ovary of both species it is associated with follicles undergoing atresia. It is present in the newborn and immature testis tubules and after puberty only in the Leydig cells. A distinct GR-LACS protein species of 64 kDa that was more abundant than the 79 kDa long form was found in the rat brain. Also, a minor 73 kDa form was observed in the rat brain and mouse ovary. Two novel species resulting from alternatively splicing of the GR-LACS gene were identified in a rat brain cDNA library: a short form 1 (S1) lacking exon 8 and short form 2 (S2) lacking exons 6-8. Expression studies revealed that the sizes of the S1/S2 proteins are comparable to those of the endogenous variant species. Neither S form contains FACSs activity, suggesting that exon 8 is essential for the enzymatic function. GR-LACS variants exhibit small but significant dominant negative effects on the FACS activity of the long form. GR-LACS variants may regulate the long form's activity in the brain.

Adrenal Glands↗
PubMed1988

Corticosteroid receptor analyses in rat and hamster brains reveal species specificity in the type I and type II receptors.

In vitro cytosol binding, receptor autoradiography with radiolabelled corticosteroid analogs, and immunocytochemistry with monoclonal antibodies have revealed the presence of two receptor systems for corticosteroids in rat and hamster brains. The type I receptor is found mainly in the hippocampal region, and in the hamster it binds cortisol (F) and corticosterone (B) with similar affinity while in the rat (a species which unlike the hamster secretes solely B) the type I receptor shows high affinity to B and not to F. The type II receptor is more widely distributed in the brain and it binds to F (hamster) or B (rat) with affinity 4-6-fold lower than to the type I. in vivo, the hamster type I and II retain F much more than B while those in the rat show the opposite. In conclusion, the present study clearly indicates species-specificity in type I and type II receptor systems in these animals. Furthermore, the type I receptor displays in vivo stringent preference for retention of the animal's predominantly circulating corticosteroid (F in hamster, in B in rat).

Adrenalectomy↗
PubMed1997

Selective, physiological transport of insulin across the blood-brain barrier: novel demonstration by species-specific radioimmunoassays.

Insulin in blood is thought to cross the blood-brain barrier (BBB) to act within the brain to help control appetite. We examined the ability of blood-borne insulin to cross the BBB. Human insulin was infused for 48 h subcutaneously at several doses into mice and the amount of human and murine insulin in serum and brain measured with species-specific radioimmunoassays. For the exogenous human insulin, both brain and blood concentrations increased with increasing doses of infused insulin, whereas for the endogenous murine insulin, brain and blood concentrations decreased. Since the mouse cannot make human insulin, blood was the only source for the human insulin in brain, demonstrating that insulin does indeed cross the BBB. The relationship between the concentrations of human insulin in brain and blood was nonlinear, showing that passage is by a saturable mechanism. Partial saturation of the transporter occurred at euglycemic concentrations of serum insulin. Thus, insulin enters the brain by a saturable transport system that is operational primarily at physiological levels of serum insulin.

Animals↗
PubMed1982

The molecules that initiate cardiac hypertrophy are not species-specific.

Extracts from hypertrophying dog hearts perfused through isolated rat hearts increase the synthesis of messenger RNA and initiate hypertrophy in the treated hearts. Total RNA extracted from experimental and control hearts was translated in vitro and hybridized with polyuridylate. Synthesis of protein and polyadenylate-containing RNA was greater in rat hearts perfused with extracts of hypertrophying dog hearts than in control hearts. The results demonstrate that molecules from hypertrophying dog hearts are not species-specific since they are effective in stimulating transcription of messenger RNA in rat hearts as well as in dog hearts.

Animals↗
PubMed1989

Species-specific effects of neurotensin on gallbladder contraction in vitro.

We have previously shown that an in vivo administration of neurotensin (NT) stimulates contraction of dog gallbladder (GB), but produces dilatation of GB in humans. The objective of this study was to examine the effect of NT on human, dog, guinea pig, and rabbit GB in vitro, in order to delineate direct versus indirect actions of NT in different species and to evaluate the structure-activity relationships of NT. The effect of NT on the canine sphincter of Oddi (SOD) was also examined in vitro. Isolated longitudinal strips of GB from the four species given above and SOD from dogs were suspended in oxygenated Krebs buffer, and the isometric tension responses to various doses of NT, NT 8-13, NT 1-11, and xenopsin (XP) were determined. All the NT homologs, except NT 1-11, stimulated contraction of the dog GB and SOD in a dose-dependent manner. NT also caused dose-related stimulation of GB contraction from guinea pigs but did not stimulate or depress the contractile activity of human and rabbit GB strips. These results suggest that NT action on GB contraction is species-specific. Tetrodotoxin did not modify the contraction of dog GB and SOD in response to NT, indicating that NT mediates its contractile effects directly. The relaxing effect of NT on GB of humans in vivo, as previously reported by us, thus appears to be an indirect action.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Comparison of the rompA gene repeat regions of Rickettsiae reveals species-specific arrangements of individual repeating units.

Genes containing repeating units have been described for several eukaryotic and prokaryotic proteins, although none exhibit the extraordinary length and conservation seen with the Rickettsia rickettsii 190-kDa protein (OmpA) repeat region. The genetic organization of the repeat regions of the ompA gene for R. conorii and R. akari was examined and compared to that of R. rickettsii. Individual repeating units, which constitute the makeup of the repeat regions, share extensive DNA homology among these species. However, differences were observed in the overall numbers and arrangements of repeating units within each species' repeat region. It appears that the distinctive arrangement of repeating units within the gene may represent the basis for encoding a protective species-specific conformational epitope of the protein.

Amino Acid Sequence↗
PubMed1983

Species-specific homogeneity of the primate Alu family of repeated DNA sequences.

We have determined the base sequence of several cloned Alu family members from the DNAs of a new world monkey (owl monkey) and a prosimian (galago). The three owl monkey Alu family members reported here belong to a single 300 base pair consensus sequence which closely resembles the human Alu family consensus. The galago Alu family members can best be represented as belonging to either of two related but distinct consensus sequences. One of the two galago Alu family subgroups (Type I) more accurately resembles the human consensus sequence than does the other subgroup (Type II). In this work we compare base sequences of human and galago Type I Alu family members. There are several examples of species-specific differences between the human and Type I galago sequences indicating that the Alu family members are effectively homogenized within a species.

Animals↗
PubMed1986

Naegleria actin elicits species-specific antibodies.

Actin, the major protein of amebae of Naegleria gruberi, proved to be strongly immunogenic in rabbits. The resulting precipitating antibodies are specific to actin of Naegleria. In a competitive solid-phase radioimmunoassay, these antibodies bound similarly to Naegleria G- and F-actin. Actins from amebae of Acanthamoeba and Dictyostelium, plasmodia of Physarum, sea urchin eggs, and vertebrate muscles gave no competition in the radioimmunoassay. Estimates of the amount of actin in Naegleria amebae ranged from a minimum of 5% of the total cell protein by radioimmunoassay to a maximum of 16% by electrophoresis. The unusual species specificity of these antibodies indicates that Naegleria actin, although conserved in many properties, is different enough to have unique antigenic determinants.

Actins↗
PubMed1980

Evidence for species-specific lipid antigens in Mycobacterium leprae.

A partially purified lipid fraction from Mycobacterium leprae yielded distinct lines of precipitation with antisera from two lepromatus patients and from an infected armadillo. There was no reaction to the sera from patients with tuberculosis or a M. avium infection or to the serum from a normal armadillo. The activity in the lipid fraction was unaffected by mild alkali, and upon hydrolysis the fraction yielded 6-deoxyhexoses. This information suggests that the lipid antigens of M. leprae may be species specific and related to the A, B, C or G mycosides.

Animals↗
PubMed2005

The use of real-time PCR and species-specific primers for the identification and monitoring of Paecilomyces lilacinus.

The Paecilomyces lilacinus is the most widely tested fungus for the control of root-knot and cyst nematodes. The fungus has also been implicated in a number of human and animal infections, difficulties in diagnosis often result in misdiagnosis or delays in identification leading to a delay in treatment. Here, we report the development of species-specific primers for the identification of P. lilacinus based on sequence information from the ITS gene, and their use in identifying P. lilacinus isolates, including clinical isolates of the fungus. The primer set generated a single PCR fragment of 130 bp in length that was specific to P. lilacinus and was also used to detect the presence of P. lilacinus from soil, roots and nematode eggs. Real-time PCR primers and a TaqMan probe were also developed and provided quantitative data on the population size of the fungus in two field sites. PCR, bait and culture methods were combined to investigate the presence and abundance of the fungus from two field sites in the United Kingdom where potato cyst nematode populations were naturally declining, and results demonstrated the importance of using a combination of methods to investigate population size and activity of fungi.

Animals↗
PubMed1999

Identification, isolation, and characterization of a species-specific 30-kDa antigen of Oesophagostomum dentatum.

In the search for a serology tool for the diagnosis of nonpatent as well as patent infections with Oesophagostomum dentatum in pigs a water-soluble, unglycosilated antigen of about 30 kDa specific for the third-stage larvae of the parasite was purified by ion-exchange chromatography. In Western blots, the antigen was first detected by antibodies at day 7 postinfection. Cross-reactivity with O. quadrispinulatum, Ascaris suum, or Trichuris suis was not detected. It is suggested that this protein is a suitable tool for the species-specific serodiagnosis of O. dentatum infection in pigs.

Animals↗
PubMed1995

Identification, cloning, and characterization of PWL2, a gene for host species specificity in the rice blast fungus.

Genetic analysis of host specificity in the rice blast fungus (Magnaporthe grisea) identified a single gene, PWL2 (for Pathogenicity toward Weeping Lovegrass), that exerts a major effect on the ability of this fungus to infect weeping lovegrass (Eragrostis curvula). The allele of the PWL2 gene conferring nonpathogenicity was genetically unstable, with the frequent appearance of spontaneous pathogenic mutants. PWL2 was cloned based on its map position. Large deletions detected in pathogenic mutants guided the gene cloning efforts. Transformants harboring the cloned PWL2 gene lost pathogenicity toward weeping lovegrass but remained fully pathogenic toward other host plants. Thus, the PWL2 host species specificity gene has properties analogous to classical avirulence genes, which function to prevent infection of certain cultivars of a particular host species. The PWL2 gene encodes a glycine-rich, hydrophilic protein (16 kD) with a putative secretion signal sequence. The pathogenic allele segregating in the mapping population, pwl2-2, differed from PWL2 by a single base pair substitution that resulted in a loss of function. The PWL2 locus is highly polymorphic among rice pathogens from diverse geographic locations.

Alleles↗
PubMed2006

Stable isotope evidence of diverse species-specific and individual wintering strategies in seabirds.

Although there is increasing evidence that climatic variations during the non-breeding season shape population dynamics of seabirds, most aspects of their winter distribution and ecology remain essentially unknown. We used stable isotope signatures in feathers to infer and compare the moulting (wintering) habitat of subantarctic petrels breeding at two distant localities (South Georgia and Kerguelen). Petrels showed species-specific wintering habitat preferences, with a similar pattern of latitudinal segregation for all but one taxon. At both localities, delta13C values indicated that blue petrels (Halobaena caerulea) moult in Antarctic waters, South Georgian diving petrels (Pelecanoides georgicus) in the vicinity of the archipelagos and/or in the Polar Frontal Zone and Antarctic prions (Pachyptila desolata) in warmer waters. In contrast, common diving petrels (Pelecanoides urinatrix) showed divergent strategies, with low and high intrapopulation variation at South Georgia and Kerguelen, respectively. Birds from Kerguelen dispersed over a much wider range of habitats, from coastal to oceanic waters and from Antarctica to the subtropics, whereas those from South Georgia wintered mainly in waters around the archipelago. This study is the first to show such striking between-population heterogeneity in individual wintering strategies, which could have important implications for likely demographic responses to environmental perturbation.

Animal Migration↗
PubMed2000

Two-dimensional agarose gel electrophoresis as a tool to isolate genus- and species-specific repetitive DNA sequences.

Two-dimensional electrophoresis in agarose gels separates DNA-restriction fragments not only by molecular weight but also according to their AT-cluster content. The method produced genus-specific spot patterns of multicopy DNA fragments of grains as well as spot patterns of highly repetitive DNA fragments of ciliates, demonstrated for barley, spelt, and Tetrahymena. Further investigations in regard to their specificity by hybridization with three other grain species (wheat, oat, and rye) and three ciliate species (Tetrahymena thermophila, Tetrahymena pigmentosa, and Tetrahymena borealis) were performed. The DNA samples from spelt and Tetrahymena were demonstrated to be genus specific for Triticum and species specific for Tetrahymena pyriformis, respectively.

Animals↗