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Species specificity of the anticoagulant activity of human urinary soluble thrombomodulin.

The anticoagulant activities of human urinary soluble thrombomodulin (UTM) in blood taken from various species using several anticoagulant assay systems were compared; it was examined which coagulant assay system is appropriate for evaluation of the antithrombotic effects of UTM and how the species specificity of UTM is involved in the mechanisms of action of UTM. When anticoagulant activities were compared using activated partial thromboplastin time (APTT), thromboelastography (TEG), and thrombin generation test (TGT), the effect of UTM was found to be the strongest in humans among various species tested. Among the anticoagulant assays tested, TGT reflecting protein C (PC) activation by UTM, appeared to be more sensitive than APTT and TEG in detection of thrombomodulin activity. In the study of the mechanisms of action of UTM, UTM exhibited nearly the same antithrombin activity against human and rat thrombin; the rate of activation of human PC by thrombin/UTM complex was much higher than that of rat PC. Therefore, the species specificity of the anticoagulant activity of UTM may be attributable to thrombin/UTM-PC interaction, but not to UTM-thrombin interaction. From these results, we concluded that TGT reflecting PC activation by UTM will be a more useful assay than APTT and TEG for estimating the antithrombotic effects of UTM in humans. Furthermore, our findings suggest that UTM will exhibit more potent antithrombotic effects in humans than those in rats by strongly enhancing thrombin-catalyzed PC activation.

Animals↗

Species-specific oligonucleotides for enumeration of Pseudomonas putida F1, Burkholderia sp. strain JS150, and Bacillus subtilis ATCC 7003 in biodegradation experiments.

Species-specific sequences were identified within the V4 variable region of 16S rRNA of two bacterial species capable of aromatic hydrocarbon metabolism, Pseudomonas putida F1 and Burkholderia sp. strain JS150, and a third, Bacillus subtilis ATCC 7003, that can function as a secondary degrader. Fluorescent in situ hybridization (FISH) with species-specific oligonucleotides was used for direct counting of these species throughout a phenol biodegradation experiment in batch culture. Traditional differential plate counting methods could not be used due to the similar metabolism and interactions of the primary degraders and difficulties in selecting secondary degraders in mixed culture. In contrast, the FISH method provided reliable quantitative results without interference from those factors.

Bacillus subtilis↗

TBP-associated factors interact with DNA and govern species specificity of RNA polymerase I transcription.

Unlike genes transcribed by RNA polymerases II and III, transcription by RNA polymerase I is highly species-specific. Ribosomal promoter selectivity is brought about by a multisubunit transcription factor (SL1/TIF-IB) which consists of the TATA-binding protein (TBP) and three TBP-associated factors (TAFs). To determine the basis for the inability of SL1/TIF-IB to recognize heterologous rDNA, the transcriptional properties and the subunit composition of the murine and the human factor, as well as a chimeric complex containing epitope-tagged human TBP and murine TAFs, have been compared. We show that TBP can be exchanged between the human and mouse factor indicating that the variable N-terminal domain of TBP does not play a significant role in rDNA promoter selectivity. Instead, DNA binding is brought about by the TAFs. UV crosslinking experiments demonstrate that binding to the ribosomal gene promoter is mediated by two TAFs (TAFI48 and TAFI68) which have the same electrophoretic mobility in the human and mouse factor. The largest TAF is different in both species and is suggested to play a role in the species-specific assembly of productive preinitiation complexes. Thus, evolutionary changes of rDNA promoter sequences have been accompanied by changes in specific TAFs.

Amino Acid Sequence↗

Physical localisation of repetitive DNA sequences in Alstroemeria: karyotyping of two species with species-specific and ribosomal DNA.

Fluorescence in situ hybridization (FISH) was used to localise two species-specific repetitive DNA sequences, A001-I and D32-13, and two highly conserved 25S and 5S rDNA sequences on the metaphase chromosomes of two species of Alstroemeria. The Chilean species, Alstroemeria aurea (2n = 16), has abundant constitutive heterochromatin, whereas the Brazilian species, Alstroemeria inodora, has hardly any heterochromatin. The A. aurea specific A001-I probe hybridized specifically to the C-band regions on all chromosomes. The FISH patterns on A. inodora chromosomes using species-specific probe D32-13 resembled the C-banding pattern and the A001-I pattern on A. aurea chromosomes. There were notable differences in number and distribution of rDNA sites between the two species. The 25S rDNA probe revealed 16 sites in A. aurea that closely colocalised with A001-I sites and 12 in A. inodora that were predominantly detected in the centromeric regions. FISH karyotypes of the two Alstroemeria species were constructed accordingly, enabling full identification of all individual chromosomes. These FISH karyotypes will be useful for monitoring the chromosomes of both Alstroemeria species in hybrids and backcross derivatives.

Brazil↗

A 35-kDa protein is the basic unit of the core from the 2 x 10(4)-kDa aggregation factor responsible for species-specific cell adhesion in the marine sponge Microciona prolifera.

Dissociated sponge cells quickly reaggregate in a species-specific manner, differentiate, and reconstruct tissue, providing a very handy system to investigate the molecular basis of more complex intercellular recognition processes. Species-specific cell adhesion in the marine sponge Microciona prolifera is mediated by a supramolecular complex with a Mr = 2 x 10(7), termed aggregation factor. Guanidinium hydrochloride/cesium chloride dissociative gradients and rhodamine B isothiocyanate staining indicated the presence of several proteins with different degrees of glycosylation. Hyaluronate has been found to be associated with the aggregation factor. Chemical deglycosylation revealed a main component accounting for nearly 90% of the total protein. The cDNA-deduced amino acid sequence predicts a 35-kDa protein (MAFp3), the first sponge aggregation factor core protein ever described. The open reading frame is uninterrupted upstream from the amino terminus of the mature protein, and the deduced amino acid sequence for this region has been found to contain a long stretch sharing homology with the Na+-Ca2+ exchanger protein. A putative hyaluronic acid binding domain and several putative N- and O-glycosylation signals are present in MAFp3, as well as eight cysteines, some of them involved in intermolecular disulfide bridges. Northern blot data suggest variable expression, and Southern blot analysis reveals the presence of other related gene sequences. According to the respective molecular masses, one aggregation factor molecule would contain about 300 MAFp3 units, suggesting that sponge cell adhesion might be based on the assembly of multiple small glycosylated protein subunits.

Amino Acid Sequence↗

Role of a vitelline layer-associated 350 kDa glycoprotein in controlling species-specific gamete interaction in the sea urchin.

The process of sperm-egg binding is one of the barriers to cross-fertilization between related sea urchin species. A 350 kDa glycoprotein in the egg vitelline layer of Strongylocentrotus purpuratus has been shown to be a sperm-binding protein (SBP). Sulfated O-linked oligosaccharide chains on the 350 kDa glycoprotein, as well as domains of the polypeptide chain, serve as ligands for this binding process. The hypothesis that species-specific sperm-egg binding is attributed to the interaction between the sperm and the 350 kDa glycoprotein was tested using S. purpuratus and S. franciscanus. It was found that both species had a 350 kDa glycoprotein on the egg surface that cross-reacted immunologically using antibodies prepared against a recombinant form of the SBP. Because earlier studies had implicated the carbohydrate chains of the 350 kDa glycoprotein of S purpuratus in sperm binding, differences in carbohydrate chains on the 350 kDa glycoproteins of these species were examined. It was found that among the lectins tested only wheat germ agglutinin and Sambucus nigra agglutinin showed a significant difference in reactivity to the 350 kDa glycoproteins between species. Finally, using a bead-binding assay, it was shown that the isolated 350 kDa glycoproteins exhibited species-specific sperm-binding activity.

Animals↗

Organ and species specificity of the messenger RNA transport factor.

The transport of messenger RNA from isolated rat liver nuclei is dependent on a 35,000 dalton protein localized in the cytoplasm. The tissue and species specificity of this protein are reported. The factor from female rat liver or from rat brain, kidney, or hepatoma supports the transport of messenger RNA from male rat liver nuclei. Messenger RNA is also transported in response to the factor from beef and chicken liver. The cytosols from rat erythrocytes, amoeba and yeast were inactive in the rat liver system. The results indicate that the messenger RNA transport factor is not specific for the nucleotide sequence of the coding portion of the messenger RNA and that it is not organ or species specific within the vertebrates.

Amoeba↗

Rat ribosomal RNA gene can utilize primate RNA polymerase I transcription machinery: lack of absolute species specificity in rDNA transcription.

The transcriptional activity of rodent ribosomal RNA gene (rDNA) in the primate cell was examined in the light of reported species specificity of eukaryotic ribosomal RNA synthesis. The present study showed that rat rDNA can be transcribed in HeLa nuclear extract whereas mouse rDNA was not transcribed in the heterologous extract. Rat and mouse rDNA transcription factors were interchangeable with respect to efficiency and accuracy of transcription. The initiation of rat ribosomal gene transcription by RNA polymerase I occurred at the +1 site in the heterologous extract. Initiation of transcription at the correct site also occurred in vivo following transfection of cloned rat rDNA into the primate (COS-7) cells. These data indicate that rat ribosomal RNA gene can be expressed in the primate system in vitro and in vivo. The absolute lack of species specificity in rDNA transcription has been discussed based on the present data and other reports.

Animals↗

Presence of species-specific, monomorphic antigens on sheep and goat binucleate cells.

Immunocytochemical assays for sheep and goat species-specific, monomorphic antigens were developed utilizing polyclonal antisera from sheep and goats immunized by interspecific pregnancy. The assays were applied to cell isolates from sheep and goat fetal cotyledons collected from allogeneic pregnancies at Days 35, 40 and 120 of gestation. The isolates contained 7 to 48% binucleate cells (BNC). Using these assays, the sheep-specific antigen was detected on sheep cotyledonary cell isolates on all days of gestation tested (P < 0.001); the assay also detected the antigen on the BNC subset of the cotyledonary cell isolate population (P < 0.001). The caprine-specific antigen was shown to be present on cotyledonary cell isolates (P < 0.05), although the presence of the antigen could not be demonstrated with statistical confidence on goat BNC due to insufficient numbers of discernible cells. Binucleate cells contribute to the formation of the syncytial layer of the placenta by fusing with maternal epithelial cells and with the syncytium. The species-specific antigen (or antigens) is present on BNC at the appropriate time of gestation at which it (they) could play a role in the humoral immune response to interspecific and hybrid pregnancies observed in ewes and does.

Journal Article↗

Development of species-specific hybridization probes for marine luminous bacteria by using in vitro DNA amplification.

By using two highly conserved region of the luxA gene as primers, polymerase chain reaction amplification methods were used to prepare species-specific probes against the luciferase gene from four major groups of marine luminous bacteria. Laboratory studies with test strains indicated that three of the four probes cross-reacted with themselves and with one or more of the other species at low stringencies but were specific for members of their own species at high stringencies. The fourth probe, generated from Vibrio harveyi DNA, cross-reacted with DNAs from two closely related species, V. orientalis and V. vulnificus. When nonluminous cultures were tested with the species-specific probes, no false-positive results were observed, even at low stringencies. Two field isolates were correctly identified as Photobacterium phosphoreum by using the species-specific hybridization probes at high stringency. A mixed probe (four different hybridization probes) used at low stringency gave positive results with all of the luminous bacteria tested, including the terrestrial species, Xenorhabdus luminescens, and the taxonomically distinct marine bacterial species Shewanella hanedai; minimal cross-hybridization with these species was seen at higher stringencies.

Base Sequence↗

Detection and identification of fungi in blood using broad-range 28S rDNA PCR amplification and species-specific hybridisation.

The aim of the present study was to develop a PCR-based method to detect and identify fungi directly from human venous blood. We used broad-range PCR primers that targeted a part of the large subunit 28S rRNA genes. To obtain species-specific hybridisation probes, type strains of Candida albicans, C. glabrata, C. krusei, C. parapsilosis, C. tropicalis and Cryptococcus neoformans were PCR amplified, and the amplicons were analysed by gene sequencing. Based on the sequence analysis, species-specific probes that targeted variable regions were designed and used in hybridisation analyses. Between 2 to 10 fungal cells/ml of spiked blood samples could be detected and correctly identified to species. We applied the technique to blood samples obtained from two patients with or two patients without verified candidaemia. The three samples of candidaemia patients were correctly identified to species level, and those of the negative patients remained negative. This method is a potential tool for diagnosis of systemic invasive candidiasis.

Blotting, Southern↗

On the species specificity of sperm binding and sperm penetration of the zona pellucida.

Sperm binding and sperm penetration of the zona pellucida (zp) are regarded as species-specific. In this investigation, the interactions between bovine oocytes and porcine, respectively, equine spermatozoa have been studied under in vitro conditions and compared with the normal in vitro fertilization of bovine oocytes by bovine sperm. Surprisingly, many of the heterologous spermatozoa adhered firmly to the bovine oocytes and could not be removed by intense washing. On average, more than 100 boar or equine spermatozoa were bound to the zp of bovine oocytes. Electron microscopic studies clearly demonstrated that porcine sperm attached to the zona and underwent the acrosome reaction. Equine spermatozoa displayed a similar binding affinity, but unlike the porcine spermatozoa even penetrated the zp and were taken up into the oocyte after a longer period of co-incubation. Considering these new results the dogma of a strict species specificity of sperm zona interactions under in vitro conditions has to be reconsidered.

Acrosome↗

Direct measurement of species-specific cohesion in cellular slime molds.

Partially differentiated cells of two species of cellular slime molds, Dictyostelium discoideum and Dictyostelium purpureum, were labeled with isothiocyanate derivatives of fluorescent dyes. The labeled cells of each species segregated promptly when mixed and placed on moist filters. We determined whether cells studied at a time when they demonstrated this capacity to segregate showed a preferential adherence to cells of the same species. When labeled dissociated cells of each species were interacted with an unlabeled immobilized layer of cells of each species under appropriate conditions, binding was, in part, species-specific.

Dictyostelium↗

Failure to detect mouse species-specific antigens in Toxoplasmin Sevac.

Toxoplasmin--a highly purified extract from the protozoa Toxoplasma gondii propagated in mice--was tested for the presence of the mouse species-specific antigens by immunodiffusion in agar gel and by PCA test. Neither test gave positive reaction. It was concluded therefore that Toxoplasmin Sevac used for the detection of dermal hypersensitivity to toxoplasma antigens in humans does not contain any detectable contamination by mouse species-specific antigens within the limits of sensitivity of both methods used.

Animals↗

Species specificity of leukocytic pyrogens.

Polymorphonuclear neutrophilic leukocytes of the dog, cat, and goat release leukocytic pyrogen under the same conditions as the heterophile polymorphonuclear leukocytes of the rabbit. The characteristics of the febrile response to an intravenous injection of homologous leukocytic pyrogen in all four species are very similar: a brisk monophasic fever reaching a peak between 30 and 50 min with smooth defervescence to the baseline by 3 hr. Shivering, which is not obvious in the rabbit, is noted in the dog, cat, and goat during the first 30 min. Quantitative differences in response reveal the cat to be the most sensitive of of these species to homologous leukocytic pyrogen, followed by the rabbit, dog, and goat. The response to heterologous pyrogen is in most cases markedly diminished compared to that after equal doses of homologous protein, suggesting the operation of species specificity, although canine and feline pyrogen behaved very similarly in all tests. Species specificity of leukocytic pyrogen is probably related to amino acid substitutions in different species of a common mammalian protein effector molecule.

Animals↗

Rapid and reliable identification of Staphylococcus equorum by a species-specific PCR assay targeting the sodA gene.

Rapid and reliable identification of Staphylococcus (S.) equorum was achieved by species-specific PCR assays. A set of primers targeting the manganese-dependent superoxide dismutase (sodA) gene of S. equorum was designed. Species-specificity of the primer set was evaluated by using a total of 112 strains (including 27 reference strains of the DSM collection), representing 26 different species of the genus Staphylococcus, 3 species of the genus Kocuria, and different strains of Macrococcus caseolyticus. By using primers SdAEqF and SdAEqR the expected PCR fragment was obtained only when DNA from S. equorum strains was used as template. The rapidity (about 4 h from DNA isolation to results) and reliability of the PCR procedures established suggests that the method may be profitably applied for specific detection and identification of S. equorum strains.

Bacterial Proteins↗

Interleukin-15 interactions with interleukin-15 receptor complexes: characterization and species specificity.

Interleukin (IL-) 2 and IL-15 share the IL-2 receptor betagamma c subunits (IL-2Rbetagamma c) but have specific, unique alpha receptor subunits. We studied species specificity of human (hu), simian (si), and mouse (mu) IL-15 and found that hu and si IL-15 behaved similarly in all systems investigated. Hu and mu IL-15 bound hu or mu IL-15Ralpha with equal high affinity in the presence or absence of IL-2Rbetagamma c and exhibited similar proliferative activities on cells containing all three subunits. However, quantitative differences were noted in the specific activity of hu and mu IL-15 in both in vitro and in vivo systems utilizing IL-2Rbetagamma c in the absence of IL-15Ralpha. These data show that hu IL-15 may be used in mouse model systems, however care must be taken when comparing the efficacy and toxicity of cytokines across species.

Animals↗

The vectorial competence of Phlebotomus sergenti is specific for Leishmania tropica and is controlled by species-specific, lipophosphoglycan-mediated midgut attachment.

The vectorial competence of Phlebotomus sergenti for 3 Old World species of Leishmania, L. tropica, L. major and L. donovani, was investigated in vivo and by in vitro midgut binding assays using living promastigotes and purified lipophosphoglycan (LPG). P. sergenti consistently showed a high specificity for L. tropica strains, which were able to develop mature, potentially transmissible infections. The loss of infection with L. major and L. donovani correlated with the excretion of the digested bloodmeal. These strains were able to produce sustained infections in the midguts of their appropriate vectors, P. papatasi and P. argentipes, respectively. In in vitro binding assays, a significantly higher number of L. tropica procyclic promastigotes attached to the midgut lining of P. sergenti, compared to those of L. major and L. donovani (P < 0.05). The prediction that the species specificity of midgut attachment is controlled by polymorphic structures on the parasite LPG was supported by the finding that P. sergenti midguts were intensely stained following incubation with purified phosphoglycan (PG) from L. tropica compared with PGs from L. major or L. donovani. The results provide further evidence that LPG structural polymorphisms are driven by the species diversity of molecules present on the sandfly midgut that function as parasite attachment sites.

Animals↗