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Species specificity of guinea pig erythropoietin.

Various stimuli (hypoxic hypoxia, bleeding, carbon monoxide hypoxia and cobalt administration), well known to increase erythropoietin plasma level in many species including man, failed to increase the erythropoietin activity in plasma of guinea pigs when measured in the polycythaemic mice assay. Nevertheless, the plasma of these guinea pigs stimulated the erythropoiesis in polycythaemic guinea pigs which, however, failed to respond to rat erythropoietin. From this it was concluded that not only the erythropoietin, but also the erythropoietin responsive cells in the bone marrow of guinea pigs are species specific. Bilateral nephrectomy in guinea pigs exposed to hypoxia prevented the increase in the erythropoietin plasma level, thus suggesting that, similarly as in other species, also in guinea pigs the kidney is the main organ of erythropoietin elaboration. The species specificity of guinea pig erythropoietin - erythropoiesis system is an interesting exception among mammals, since the erythropoietin of a large number of species belonging to this class was demonstrated to lack species specificity.

Animals↗

The mouse DNA polymerase alpha-primase subunit p48 mediates species-specific replication of polyomavirus DNA in vitro.

Mouse cell extracts support vigorous replication of polyomavirus (Py) DNA in vitro, while human cell extracts do not. However, the addition of purified mouse DNA polymerase alpha-primase to human cell extracts renders them permissive for Py DNA replication, suggesting that mouse polymerase alpha-primase determines the species specificity of Py DNA replication. We set out to identify the subunit of mouse polymerase alpha-primase that mediates this species specificity. To this end, we cloned and expressed cDNAs encoding all four subunits of mouse and human polymerase alpha-primase. Purified recombinant mouse polymerase alpha-primase and a hybrid DNA polymerase alpha-primase complex composed of human subunits p180 and p68 and mouse subunits p58 and p48 supported Py DNA replication in human cell extracts depleted of polymerase alpha-primase, suggesting that the primase heterodimer or one of its subunits controls host specificity. To determine whether both mouse primase subunits were required, recombinant hybrid polymerase alpha-primases containing only one mouse primase subunit, p48 or p58, together with three human subunits, were assayed for Py replication activity. Only the hybrid containing mouse p48 efficiently replicated Py DNA in depleted human cell extracts. Moreover, in a purified initiation assay containing Py T antigen, replication protein A (RP-A) and topoisomerase I, only the hybrid polymerase alpha-primase containing the mouse p48 subunit initiated primer synthesis on Py origin DNA. Together, these results indicate that the p48 subunit is primarily responsible for the species specificity of Py DNA replication in vitro. Specific physical association of Py T antigen with purified recombinant DNA polymerase alpha-primase, mouse DNA primase heterodimer, and mouse p48 suggested that direct interactions between Py T antigen and primase could play a role in species-specific initiation of Py replication.

Animals↗

Species specific chlamydiae antibodies in voluntary blood donors of Delhi.

BACKGROUND & OBJECTIVES: Different species of genus Chlamydia have been associated with ocular, genitourinary and respiratory infections, and coronary artery disease. Since the majority of these infections remain asymptomatic or subclinical, antibodies may be present in apparently healthy individuals, and the determination of species specific Chlamydia antibodies in a healthy population may reflect exposure. We therefore screened the sera of healthy blood donors for species specific Chlamydia antibodies by microimmunofluorescence assay. METHODS: Sera of 844 voluntary blood donors from Delhi were screened by microimmunofluorescence assay using specific antigens of C. trachomatis (18 serovars divided in 3 pools of serotypes A-C, D-K and L1-L3), C. psittaci and C. pneumoniae for Chlamydia antibodies. RESULTS: A total of 470 (55.69%) blood donors were found positive for Chlamydia antibodies. Of these, 361(42.77%) were positive for C. pneumoniae, 106 (12.5%) for C. trachomatis [of which 72 (8.5%) were against serotypes D-K and 34(4%) were against serotypes A-C]. There donors (0.3%) had antibodies to C. psittaci. INTERPRETATION & CONCLUSION: The results suggested that more than half of the study population (55.69%) is exposed to one or other species of chlamydiae. Majority of the donors (44.7%) had C. pneumoniae antibodies, suggesting the presence of widespread apparent or inapparent C. pneumoniae infection. The findings also suggest that Chlamydia antibody testing for the diagnosis of chlamydial infections may not be helpful due to the presence of antibodies in a large proportion of healthy individuals.

Antibodies, Bacterial↗

Species-specific hypoglycemic activity of triphenylphosphoranylideneacetophenones.

The species-specific hypoglycemic activity of two 2-triphenylphosphoranylideneacetophenones is described. 2-Triphenylphosphoranylideneacetophenone (SK&F 45359) and 2-triphenylphosphoranylidene-m-trifluoromethyl-acetophenone (SK&F 62775) were hypoglycemic in various rat models, but failed to exhibit hypoglycemic activity in other species.

Acetophenones↗

Species-specific heavy metal accumulation patterns of earthworms on a floodplain in Japan.

We identified all earthworm species found on a floodplain contaminated by heavy metals (Cu, Zn, Cd, and Pb) from an old mine in central Japan and compared their abundance, biomass, and heavy metal concentrations in tissue. There were six species belonging to three families: Megascolecidae, Moniligastridae, and Lumbricidae. Earthworm community structure seemed to be influenced mostly by soil properties, especially pH and clay fraction. Despite the same endogeic characteristics, species-specific patterns of heavy metal accumulation were observed: species in Megascolecidae and Lumbricidae had relatively lower concentrations compared to those in Moniligastridae. Within Moniligastridae, Drawida sp. accumulated Cu and Pb markedly higher than Drawida japonica. Based on heavy metal concentrations in extracts of CaCl(2) and diethylenetriaminepentaacetic acid, the aging caused remarkably low concentrations in pore water, indicating low availability by dermal uptake. Therefore the different patterns of heavy metal accumulation among species would partly result from species-specific gut process.

Animals↗

Species specificity of anticoagulant activity of activated human protein C: involvement of factor V as well as protein S.

Activated protein C (APC) possesses species specificity in its anticoagulant activity. Human APC exerts only weak activity in rat plasma compared with that in human plasma. The present study was undertaken to estimate the difference in interaction of human and rat factors with human APC and to assess the cause of the species specificity. Human or rat protein S (PS), factor V, or factor VIII was used to supplement human plasma depleted of each respective factor, and the anticoagulant activity of human APC was measured in term of the elongation of activated partial thromboplastin time (APTT). The activity of human APC in rat PS- or factor V-supplemented plasma was weaker than that in the human PS- or factor V-supplemented plasma. Furthermore, using purified human and rat factor V, human APC showed weaker inactivation of rat factor V than human factor V. Equal anticoagulant activity was observed in human or rat factor VIII-supplemented plasma. And there was a little difference in the interaction of APC with its inhibitors in human or rat plasma during a few minutes of incubation as judged by measurement of residual activity by an enzyme capture assay. From these results factor V as well as PS seems to play a major role in the species specificity of APC.

Animals↗

Importance of species-specific antigens in the serodiagnosis of Chlamydia trachomatis reactive arthritis.

OBJECTIVES: To determine the most sensitive and specific method of anti-Chlamydia antibody measurement for the serodiagnosis of Chlamydia trachomatis reactive arthritis. METHODS: Immunoblotting, enzyme-linked immunosorbent assays using six synthetic peptides or recombinant antigens and a microimmunofluorescence test were used to determine the presence of IgG, IgM and IgA in serum samples from 17 patients with C. trachomatis reactive arthritis. Twenty patients with other inflammatory arthropathies without evidence of urogenital C. trachomatis infection were used as controls. RESULTS: The best association of sensitivity (76%) and specificity (85%) was obtained when IgG and/or IgA reactivity to two species-specific antigens was determined. These antigens were synthetic peptides, derived from species-specific epitopes in the variable domain IV of the major outer membrane protein (MOMP) (Labsystems, Finland) and recombinant polypeptide encoded by open reading frame 3 of the plasmid (pgp3). CONCLUSIONS: IgG and/or IgA anti-MOMP-derived peptides and anti-pgp3 could be useful for the diagnosis of probable C. trachomatis reactive arthritis.

Adolescent↗

Immunochemical characterization of a heat-stable surface antigen of Mycoplasma pulmonis expressing both species-specific and strain-specific determinants.

We sought to characterize the strain-specific antigens of four strains of Mycoplasma pulmonis (47, 63, Negroni, and 19612) by crossed immunoelectrophoresis. Although the strains possessed a number of common antigens, type-specific antigens of 0.32 mobility (bovine albumin was assigned a value of 1) were detected in strains 47 and 63. Strains 19612 and Negroni cross-reacted and represented a third group. Each strain possessed a major heat-stable antigen complex of 0.32 mobility characterized by a faster-moving component of 0.55 mobility. Monospecific antiserum to heat-stable antigen 0.32 of strain 63 demonstrated that this antigen complex consisted of at least three antigen-antibody precipitating systems characterized by type-specific and group-specific determinants. Adsorption of antiserum with whole cells revealed that the 0.32 antigen complex was surface exposed. The antigen complex is pronase sensitive and only partially sensitive to periodate. Purification of antigen 0.32 from detergent-extracted cells by affinity chromatography using monospecific antiserum revealed two major polypeptides of 86,500 and 83,500 dalton which reacted strongly with monospecific antiserum by immunoblotting. These reactive polypeptides were present in all strains examined. Additional polypeptides of different molecular weights in strains 19612 and Negroni produced strong reactions with monospecific antiserum, although sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of the two strains were strikingly similar. Common heat-stable antigens were observed also. This study demonstrates that M. pulmonis strains possess an antigenically variable heat-stable surface antigen which is unique in that it contains not only strain-specific determinants but also species-specific determinants.

Antigens, Surface↗

Cohesin-dockerin interactions within and between Clostridium josui and Clostridium thermocellum: binding selectivity between cognate dockerin and cohesin domains and species specificity.

The cellulosome components are assembled into the cellulosome complex by the interaction between one of the repeated cohesin domains of a scaffolding protein and the dockerin domain of an enzyme component. We prepared five recombinant cohesin polypeptides of the Clostridium thermocellum scaffolding protein CipA, two dockerin polypeptides of C. thermocellum Xyn11A and Xyn10C, four cohesin polypeptides of Clostridium josui CipA, and two dockerin polypeptides of C. josui Aga27A and Cel8A, and qualitatively and quantitatively examined the cohesin-dockerin interactions within C. thermocellum and C. josui, respectively, and the species specificity of the cohesin-dockerin interactions between these two bacteria. Surface plasmon resonance (SPR) analysis indicated that there was a certain selectivity, with a maximal 34-fold difference in the K(D) values, in the cohesin-dockerin interactions within a combination of C. josui, although this was not detected by qualitative analysis. Affinity blotting analysis suggested that there was at least one exception to the species specificity in the cohesin-dockerin interactions, although species specificity was generally conserved among the cohesin and dockerin polypeptides from C. thermocellum and C. josui, i.e. the dockerin polypeptides of C. thermocellum Xyn11A exceptionally bound to the cohesin polypeptides from C. josui CipA. SPR analysis confirmed this exceptional binding. We discuss the relationship between the species specificity of the cohesin-dockerin binding and the conserved amino acid residues in the dockerin domains.

Amino Acid Sequence↗

[Determination of Staphylococcus species-specific antigens by using erythrocyte reagents].

Species-specific (Staphylococcus aureus and S. epidermidis) antigenic and antibody erythrocyte diagnosticums have been prepared. Various tests made with the use of these diagnosticums have demonstrated that the activity of specific antigens is higher in hydrochloric acid extracts than in trichloroacetic and phenolic ones; this activity is linked with undialyzed components and depends on the peculiar features of the strain.

Animals↗

Detection and measurement of species-specific malarial antibodies by immunofluorescence tests.

Species-specific serodiagnosis of malaria could be made by means of the standardized indirect fluorescent antibody test, either by determination of the usual end-point titres or by fluorescent intensity measurements on antigens. The malarial antibody levels could also be measured by the fluorescent intensity measurements at a single serum dilution. Thus the fluorescent intensity measurements could effectively replace the end point titre determination, with the advantages of standardization and saving in technician time.

Adolescent↗

The species specificity of the microimmunofluorescence antibody test and comparisons with a time resolved fluoroscopic immunoassay for measuring IgG antibodies against Chlamydia pneumoniae.

AIMS: To examine the species specificity of the microimmunofluorescence test (MIF) and assess a time resolved fluoroscopic immunoassay (TRIA) for measuring IgG antibodies to C pneumoniae. METHODS: Sera from 1020 subjects were tested by MIF for IgG, IgM, and IgA antibodies to C pneumoniae, C trachomatis, and C psittaci; 501 serum samples were also tested by TRIA for IgG antibodies to C pneumoniae. RESULTS: C pneumoniae antibody titres as measured by MIF were correlated with those for C psittaci and trachomatis. It was estimated that on average, one third of the twofold dilution steps that make up the final C pneumoniae antibody titre may be due to cross reacting genus specific antibody. The results of TRIA correlated well with those of MIF. In 75% of cases, the TRIA result predicted a three titre range within which the actual MIF result would fall. CONCLUSIONS: MIF does not appear to be as species specific as claimed. TRIA is unlikely to be as specific but as it is completely objective, easier to perform, amenable to automation, and gives reproducible results, it is a rapid and useful method for comparing populations.

Aged↗

Species-specific PCR primers for Pythium developed from ribosomal ITS1 region.

AIMS: To develop a specific method for distinguishing and detecting Pythium species. METHODS AND RESULTS: Twenty PCR primers were designed from the sequences of the rDNA internal transcribed spacer 1 (ITS1) region from 34 Pythium species. The specificity of these forward primers paired with ITS2 or ITS4 and reverse universal primers was tested. Five species-specific primers were obtained, other primers showed different specificity to Pythium species. The specific amplifications enabled nine Pythium species to be differentiated. Specific detection of Pythium aphanidermatum from infested plants and P. dimorphum from soil was demonstrated. CONCLUSIONS: A method for identifying nine Pythium species using specific PCR amplification was achieved. SIGNIFICANCE AND IMPACT OF THE STUDY: Because of its rapidness and ease, the results of PCR amplified with different primers can be a powerful method for identifying Pythium species and detecting or monitoring the target fungus directly from plant material, soil and water samples.

Base Sequence↗

Isolation and partial characterization of a genus common antigen and species specific antigen of Capnocytophaga.

Sixteen strains of Capnocytophaga were isolated from the pocket of a localized juvenile periodontitis patient. These strains were divided into four groups on the basis of morphological and physiological traits. Strains from group I and group III were identified as C. ochracea and group II as C. sputigena. An antigen common to genus Capnocytophaga was purified utilizing immunoabsorbent chromatography from lysates obtained by sodium dodecyl sulfate treatment of C. ochracea strain S1. An antigen specific to C. ochracea was prepared by sequential gel filtration and preparative isoelectric focusing. The genus common and species specific antigens isolated were immunologically unique and pure when tested by immunoelectrophoresis and immunodiffusion against rabbit antisera prepared to Capnocytophaga and other gram-negative rods. The genus common antigen was susceptible to trypsin and pronase digestion, was soluble in chloroform-methanol, but was unaltered by ribonuclease and deoxyribonuclease treatments and periodate oxidation. Antigenicity of the species specific antigen was destroyed by periodate oxidation. The genus common antigen appeared to be lipid-associated protein, while the species specific antigen consisted mainly of carbohydrate. These specific immunological reagents would be valuable in diagnosing and monitoring diseases.

Age Factors↗

Trans-acting factors dictate the species-specific placental expression of corticotropin-releasing factor genes in choriocarcinoma cell lines.

CRF, in addition to its role in the hypothalamus, demonstrates species-specific expression in the placentas of higher primates, but not rodents. Transient transfections of BeWo and JEG-3 choriocarcinoma cells, as models for human trophoblasts, demonstrate regulated expression of human (h) CRF-luciferase reporter genes, whereas little or no expression is detected in other lines, including CV-1 cells. The rodent choriocarcinoma cell line, Rcho-1, a model for rodent trophoblasts, is defective in the expression of transfected hCRF genes. The mouse CRF promoter behaves similarly to the corresponding hCRF construct. It is active in BeWo and inactive in Rcho-1 cells. The transcriptional response to cAMP contributes to the specific expression of CRF. Analyses of deleted or mutated hCRF promoters identify a key role for protein kinase A-dependent pathways. A major part, but not all, of this effect is mediated by the canonical cAMP response element conserved in mouse, rat, and human CRF promoters. Additional deletions of the human CRF promoter identify control regions that also contribute to the observed species-specific expression pattern, and each identified region binds factors in nuclear extracts derived from the appropriate cell line. These studies using human and rodent choriocarcinoma cell lines as models of placental trophoblasts demonstrate dominant effects of cellular trans-acting factors, rather than DNA sequence differences, in dictating the species-specific placental expression of CRF.

Animals↗

Human erythroid 5-aminolevulinate synthase. Gene structure and species-specific differences in alternative RNA splicing.

Erythroid 5-aminolevulinate synthase (ALAS) is expressed exclusively in differentiating erythroid cells as the principal isoform of the enzyme to catalyze the first step of the heme biosynthetic pathway. The human gene encoding this isozyme was isolated from a cosmid library, and its structure was characterized with restriction mapping followed by sequencing of fragments. The gene is 22 kilobases long and has 11 exons. Exon 2 encodes the N-terminal signal sequence required for mitochondrial import, exons 3 and 4 encode a variable portion of the N-terminal end, and exons 5-11 the highly conserved C-terminal portion of the mature protein, respectively. Enzymatic amplification of human reticulocyte RNA using PCR techniques revealed two erythroid ALAS mRNA transcripts predicted to encode both the prototypical 64-kDa isoform as well as a novel smaller isoform with a deletion of 37 amino acids near the N terminus. The two mRNA isoforms are generated by alternative splicing of exon 4 and are expressed in fetal erythroid cells as well as at all stages of erythroid development tested, so that there is no evidence of differentiation-specific regulation of exon 4 splicing. However, striking species-specific differences were observed in that alternative splicing of exon 4 was found in man but not dog or mouse; also, the previously described alternative splicing within exon 3 in mouse was not observed in man. This transcript heterogeneity suggests the existence of erythroid ALAS protein isoforms with potentially distinct functional or regulatory roles. The occurrence of species-specific splicing in the least conserved region of the enzyme may reflect another mechanism of gene evolution in eukaryotes.

5-Aminolevulinate Synthetase↗

Sperm-egg binding: identification of a species-specific sperm receptor from eggs of Stronglyocentrotus purpuratus.

We have attempted to identify a surface component of echinoderm eggs that is involved in the species-specific binding of sperm. Cell surface membranes from eggs of the sea urchins Strongylocentrotus purpuratus or Arbacia punctulata were radioiodinated, detergent-treated, and subjected to density-gradient centrifugation. In the presence of bindin, the complementary binding protein isolated from sperm, one component of the membranes sedimented to a different density. This membrane component bound species specifically to sperm that had undergone the acrosome reaction. This binding led to an inhibition of the ability of treated sperm to fertilize eggs. Exhaustive proteolytic digestion of this receptor fraction yields a high molecular weight glycopeptide that can also bind to bindin. It therefore appears that this egg surface membrane fraction contains a functionally intact, species-specific receptor for sperm.

Animals↗

Selection of species-specific DNA probes which detect strain restriction polymorphism in four Bifidobacterium species.

Randomly cloned fragments (in a size range 1 to 2.5 kb) of DNA from Bifidobacterium longum ATCC 15707, B. adolescentis CIP 64.59T, B. bifidum CIP 64.65 and B. animalis ATCC 25527 were used as hybridization probes to characterize strains of these species and distinguish them from closely related Bifidobacterium species. The fragments were screened for hybridization with native DNA from 41 different Bifidobacterium strains. For each species, a fragment hybridizing specifically with DNA from strains of the same species was isolated. Each fragment was then hybridized with restriction digests in order to study the genome polymorphism. In some of the tested B. longum strains including strain ATCC 15707, the species-specific fragment L6/45 hybridized with 2 fragments instead of one as expected. Sequence of the fragment revealed the presence of an ORF which had an amino acid sequence similar to the site-specific recombinases of lambda integrase family. Moreover, Southern analysis demonstrated that at least 3 copies of this fragment are present in the chromosome of B. longum ATCC 15707 and in some other B. longum strains. The species-specific fragment A6/17 of B. adolescentis hybridized with the same restriction fragment on the eight strains of this species tested. The B. bifidum-specific fragment hybridized with different DNA restriction fragments according to the strain. The restriction fragment an1 from B. animalis ATCC 25527 hybridized with the same restriction fragment from strain B. animalis ATCC 27536. However, these two strains could be differentiated by another restriction pattern. Thus, hybridization results highlight the genetic polymorphism which exists among Bifidobacterium strains of the same species.

Base Sequence↗