bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concept, Definition, Prevalence, and Host‐Interactions of Xenosomes (Cytoplasmic and Nuclear Endosymbionts)1,2
Authors: CORLISS JOHN O. 
Published: May 2007

ABSTRACT.In this paper the concept of “xenosome” is greatly expanded from its current usage, which has been based on its application during the past 10 years by Soldo and co‐workers solely to certain bacterial invaders of the cytoplasm in species of a single genus of marine scuticociliales. The author proposes that the term now be considered to embrace all DNA‐containing, membrane‐bounded bodies or organelles—prokaryotic or eukaryotic in original nature—found within the cytoplasm or nucleus of eukaryotic cells of any or all kinds, whether the occupation (“colonization”) is temporary and transient or permanent and stable. Thus, virulent or pathogenically infectious organisms can be included as well as the commonly recognized cell endosymbionts sensu stricto, which are often mutualistic in nature. Of significance, such “normal” cell organelles as plastids, mitochondria, and even nuclei may also be embraced by this expanded definition of xenosome, based on the conjecture that these inclusions might have been “alien” or “foreign” extracellular, independent, free‐living organisms in their own past evolutionary histories. The author's enlarged concept and unifying principle allows more meaningful comparative consideration of the numerous and diverse kinds of xenosome‐host interrelationships, many of which involve species of protozoa and algae from a large number of the taxonomic groups comprising the kingdom Protista.
An Organofluorophosphate‐Hydrolyzing Activity in Tetrahymena thermophila1
Authors: LANDIS WAYNE G. , SAVAGE RUSSELL E. , HOSKIN FRANCIS C. G. 
Published: May 2007

An enzymatic activity that hydrolyzes O,O‐diisopropylphosphofluoridate (DFP) and O‐1,2,2–trimethylpropylmethyl‐phosphonofluoridate (Soman) was discovered in the ciliate protozoan Tetrahymena thermophila. The enzymatic activity classifies the protein as Mazur‐type similar to that found in hog kidney and Escherichia coli. The rate of hydrolysis of Soman by the Tetrahymena‐extract is the highest, on a per gram of extract basis, of any eucaryote. The molecular weight is approximately 75,400 as determined by Sephacryl column chromatography. A maximum fifteen‐fold purification has been achieved.Potential exists for the detoxification and one‐step detection of common organofluorophosphate pollutants. Additionally, Tetrahymena should prove an easier subject for manipulation than mammalian or squid sources. Protozoa may be a potentially important source of detoxification and degradation enzymes for other environmental contaminants.
Identification of the Basal Bodies and Kinetodesmal Fibers in Living Cells of Paramecium tetraurelia Sonneborn, 1975 and Paramecium sonneborni Aufderheide, Daggett & Nerad, 19831
Authors: AUFDERHEIDE KARL J. 
Published: May 2007

ABSTRACT. Critical use of Nomarski DIC optics and a rotocompressor permits basal bodies and kinetodesmal fibers to be visualized in the cortices of living Paramecium tetraurelia and Paramecium sonneborni. The identification of these structures is confirmed by the correspondence of the images obtained by DIC optics of living cells and by brightfield optics of fixed cells stained by the Fernández‐Galiano silver technique.Examination of cells carrying cortical inversions (portions of the cortex rotated 180°) shows that inverted regions may be identified and distinguished from normal regions by the orientation of the kinetodesmal fibers of the kinetids (cortical units) within the kineties (ciliary rows). This demonstrates that both the asymmetry and the polarity of each cortical unit may be assessed in the living cell. This technique has useful applications in the study of morphogenesis and patterning in living cells and for the screening of mutations and variants conferring altered cortical phenotypes.
Pleurotricha indica n. sp., a New Hypotrich Ciliate from the Indian Subcontinent1
Authors: AMMERMANN DIETER , SAPRA GULSHAN R. , SCHLEGEL MARTIN 
Published: May 2007

ABSTRACTA new species, Pleurotricha indica n. sp., is described, characterized by an average size of 220 × 119 μm, a firm and inflexible body, six rows of dorsal kineties, one left and two right rows of marginal cirri, and an “Oxytricha‐like” pattern of ventral cirri. The parts of the macronucleus are variable in shape and number. The comparison with other members of the genus shows that P. indica differs from other congeneric species in the combination of these characters.
Constitutive and Induced Excretion of Polypeptides in Tetrahymena thermophila1
Authors: SUHR‐JESSEN PETER 
Published: May 2007

ABSTRACTPolypeptides normally excreted to growth or starvation media were revealed using O'Farrell gel‐electrophoresis and silver‐staining. The major polypeptides detected in conditioned media were either constitutive, growth specific, starvation specific, or high‐Tris specific. The majority of the excreted polypeptides could be released from the cells by a hypo‐osomotic shock, possibly resulting in membrane leakage, but also mucocyst and/or plasma membrane‐associated polypeptides were detected in the conditioned media.
Differential Protein Synthesis During the Life Cycle of the Protozoan Parasite Trypanosoma brucei1
Authors: SHAPIRO STUART Z. , KIMMEL BRUCE E. 
Published: May 2007

ABSTRACTTwo‐dimensional polyacrylamide gel electrophoresis has been used to analyze changes in protein content and protein synthesis in three stages of the life cycle of the protozoan parasite Trypanosoma brucei. The stages examined were slender and stumpy mammalian bloodstream forms and procyclic forms, which are analogous to the tsetse fly midgut stage. Two‐dimensional gels of 35S‐methionine‐labeled proteins were examined by autoradiography to analyze newly synthesized protein, and gels were stained with ammoniacal silver to analyze proteins present. Several stage‐specific molecules were noted. The most obvious was the variant surface glycoprotein, which was only present in bloodstream forms. Some other proteins were also bloodstream form specific; they had molecular weights of 120,000 and 38,000. Proteins of 52,000, 46,000, 25–30,000, and 16,000 daltons were present both in stumpy forms and procyclics but not in slender‐form trypanosomes. Several proteins (molecular weights of 50–70,000, 43,000, 40,000, 26–24,000, 20–25,000, and 15,000) were present only in one of the three stages. One protein, a molecule of about 18,000 daltons present in both slender and stumpy parasites, did not appear to be synthesized in the stumpy stage. In vitro translation products of mRNA purified from the three stages were also examined. The abundance of mRNA encoding a protein of about 40,000 daltons appeared to be greater in slender than in stumpy parasites although the stumpy forms contained more of the protein and synthesized it at a higher rate.
Localization of Acid Phosphatase Activity in Giardia lamblia and Giardia muris Trophozoites1
Authors: FEELY DENNIS E. , DYER JOHN K. 
Published: May 2007

ABSTRACTNumerous membrane‐bounded vacuoles are found adjacent to the plasma membrane of the pathogenic protozoan Giardia lamblia. The function of these vacuoles has been discussed by several authors. Approximately 100–400 nm in diameter with a core of low electron density, they have been suggested to be mitochondria, mucocysts, lysosomes, and endocytotic vacuoles. Enzyme cytochemical localization for acid phosphatase activity using cerium as a capturing agent demonstrates reaction product in these vacuoles as well as in the endoplasmic reticulum and nuclear envelope cisternae. The distribution of reaction product suggests the vacuoles are lysosome‐like; however, their function and development remain in question.
Growth of Paramecium tetraurelia in Bacterized, Monoxenic Cultures1
Authors: ENRIGHT WILLIAM J. , HENNESSEY TODD M. 
Published: May 2007

ABSTRACTWild type and mutant Paramecium tetraurelia were grown in monoxenic cultures by first growing Enterobacter aerogenes on a defined medium and then adding the Paramecium to the stationary phase bacterial culture. The bacterial growth was proportional to the concentration of the carbon source (citrate), and the Paramecium growth was dependent upon both the bacterial density and the starting density of Paramecium. The behavior, electrophysiological properties, ciliary lipid composition, and growth characteristics were similar to the commonly used bacterized medium (Cerophyl) except that 5–10 times greater Paramecium yields were reliably obtained.
Oxidation of Fatty Acids by Leishmania braziliensis panamensis1
Authors: BLUM J. J. 
Published: May 2007

ABSTRACTHeating cultures of Leishmania braziliensis panamensis (grown at 26°C) to 34°C for 1.5–12 h transformed the cells to an ellipsoidally shaped form. The heat treatment caused an increase in the rate of oxidation of both medium and long chain fatty acids but decreased the rate of oxidation of [1‐14C]glucose. The rate of fatty acid oxidation continued to increase for times as long as 20 h after returning the cultures to 26°C. In both the promastigote and heat‐induced ellipsoidal forms, the ratio of 14CO2 release from [1‐14C]laurate to that from [12‐14C]laurate was generally larger than four, whereas this ratio from [1‐14C]oleate relative to [10‐14C]oleate was approximately two. These data show that metabolic and morphological differentiation begin after a short heat treatment and that some metabolic changes may continue even after the reverse transformation is initiated. The data also suggest that either the ω‐terminal portion of the fatty acids is not completely oxidized to acetyl CoA and/or that there are two functional fatty acid oxidation pathways in Leishmania.
Oxidation of Glucose, Ribose, Alanine, and Glutamate by Leishmania braziliensis panamensis1
Authors: KEEGAN FRANK P. , SANSONE LISA , BLUM J. J. 
Published: May 2007

ABSTRACTThe metabolism of [1‐14C]‐ and [6‐14C]glucose, [1‐14]ribose, [1‐14C]‐ and [U‐14C]alanine, and [1‐14C]‐ and [5‐14C]glutamate by the promastigotes of Leishmania braziliensis panamensis was investigated in cells resuspended in Hanks' balanced salt solution supplemented with ribose, alanine, or glutamate. The ratio of 14CO2 produced from [1‐14C]glucose to that from [6‐14C]glucose ranged from about two to six, indicating appreciable carbon flow through the pentose phosphate pathway. A functional pentose phosphate pathway was further demonstrated by the production of 14CO2 from [1‐14C]ribose although the rate of ribose oxidation was much lower than the rate of glucose oxidation. The rate of 14CO2 production from [1‐14C]glucose was almost linear with time of incubation, whereas that of [6‐14C]glucose accelerated, consistent with an increasing rate of flux through the Embden‐Meyerhof pathway during incubation. Increasing the assay temperature from 26°C to 34°C had no appreciable effect on the rates or time courses of oxidation of either [1‐14C]‐ or [6‐14C]glucose or of [1‐14C]ribose. Both alanine and glutamate were oxidized by L. b. panamensis, and at rates comparable to or appreciably greater than the rate of oxidation of glucose. The ratios of 14CO2 produced from [1‐14C]‐ to [U‐14C]alanine and from [1‐14C]‐ to [5‐14C]glutamate indicated that these compounds were metabolized via a functioning tricarboxylic acid cycle and that most of the label that entered the tricarboxylic acid cycle was oxidized to carbon dioxide. Heating the cultures for 6 or 12 h at 34°C, which converts the promastigotes into an ellipsoidally shaped intermediate form, decreased the rates of oxidation of glucose, alanine, and glutamate. The oxidation of glutamate decreased by about 50% and 70% after a 6‐h or 12‐h heat treatment, respectively. Returning the heated cultures to 26°C initiated a reversion to the promastigote form and recovery of the rate of glucose oxidation, but glutamate oxidation did not return to control levels by 19 h at 26°C.
Light and Electron Microscopical Observations on the Stomatogenesis of the Ciliate Coleps amphacanthus Ehrenberg, 1833
Authors: HUTTENLAUCH IRM , BARDELE CHRISTIAN F. 
Published: May 2007

ABSTRACTLight and electron microscopical observations on the stomatogenesis of Coleps amphacanthus Ehrenberg, 1833, show that this “gymno”‐stome ciliate has a well developed oral ciliature made of 19–23 “paroral dikinetids” and three “adoral organelles.” These structures were previously known as “circumoral ciliature” and “dorsal brosse,” and it was thought that they originated from the distal ends of all the 22–26 somatic kineties. Contrary to this view, only four stomatogenic kineties (K1, Kn, Kn‐1, and Kn‐2) are involved in stomatogenesis of the opisthe. All paroral dikinetids arise from one single kinetofragment (KF1) to the right of the oral anlage while the adoral organelles originate from the three left kinetofragments (KFn, KFn‐1, and KFn‐2). In particular, the future paroral dikinetids perform a complex morphogenetic movement that leads to a situation where the postciliary microtubules of the once posterior kinetosome of each oral dikinetid give rise to the cytopharyngeal microtubular ribbons. The postciliary origin of the cytopharyngeal ribbons which could only be detected by an EM study of stomatogenesis shows that the basket of Coleps belongs to the cyrtos‐type and not to the rhabdos‐type basket, where transverse microtubules accompany the basket‐forming nematodesmata. The taxonomic implications of these observations, which may lead to a revision of the systematic position of the genus Coleps, are discussed.
Effects of Iron‐, Manganese‐, or Magnesium‐Deficiency on the Growth and Morphology of Euglena gracilis1
Authors: HILT KENNETH L. , GORDON PHILIP R. , HEIN ANN , CAULFIELD JOHN P. , FALCHUK KENNETH H. 
Published: May 2007

ABSTRACTIron‐, manganese‐, or magnesium‐deficiency has been induced in Euglena gracilis. Each arrests cell proliferation, decreases the intracellular content of the deficient metal, and increases that of several other metals. Light and electron microscopy of stationary phase cells reveal that Fe‐deficient (‐Fe) cells are similar in size and shape to control organisms. Magnesium‐deficient (‐Mg) cells, however, are larger, and approximately 14% are multilobed, containing 2 to 12 lobes of equal size emanating from a central region. Individual (‐Mg) cells and each lobe of multilobed cells contain a single nucleus. Manganese‐deficient (‐Mn) organisms are morphologically more heterogeneous than (‐Fe) or (‐Mg) cells. Most are spherical and larger than controls. Approximately 15% are multilobed but, unlike (‐Mg) cells, contain lobes of unequal size with either zero, one, or several nuclei present in each. Nuclei of (‐Mn) cells differ in size and shape from those of control, (‐Fe), or (‐Mg) cells. All three deficient cell types accumulate large quantities of paramylon. Other cytoplasmic structures, however, appear normal. Addition of Fe, Mn, or Mg to the respective deficient stationary phase cultures reverses growth arrest and restores normal morphology. The results suggest that Fe‐, Mn‐, and Mg‐deficiencies affect different stages of the E. gracilis cell cycle.
Ultrastructural Visualization of Lipids in Trypanosomatids1
Authors: SOARES MAURÍLIO JOSÉ , DE SOUZA MARCOS FARINA , DE SOUZA WANDERLEY 
Published: May 2007

ABSTRACTAn imidazole‐buffered osmium tetroxide solution was used to visualize lipids at the ultrastructural level in the following members of the family Trypanosomatidae: Trypanosoma cruzi, T. dionisii, T. vespertilionis, T. rangeli, Crithidia deanei, C. fasciculata, C. oncopelti, and Blastocrithidia culicis. Electron‐dense material was seen in various lipid droplets found in all parasites and in the multivesicular structure of members of the sub‐genus Schizotrypanum. High contrast of some membranes, mainly those which enclose the mitochondrion, the nucleus, and the endoplasmic reticulum, was observed even in unstained sections. X‐ray microanalysis confirmed that the electron density of lipid droplets of B. culicis and membrane‐bounded dense granules of C. oncopelti was due to the presence of osmium.
Redescription of Paralagenophrys singularis (Kellicott) n. comb. (Ciliophora: Peritricha: Lagenophryidae)1
Authors: CLAMP JOHN C. 
Published: May 2007

ABSTRACTLagenophrys singularis is removed from Lagenophrys and designated the type species of Paralagenophrys n. g. Compared to members of Lagenophrys, the oral area of P. singularis is radically distorted. Paralagenophrys apparently also lacks second‐type division, a special phase of sexual reproduction characteristic of Lagenophrys and associated with its adaptation to symbiotic life on crustaceans. Members of Lagenophrys are obligate ectocommensals of crustaceans. In contrast, P. singularis (Kellicott, 1887) n. comb. occurs most often on the leaves of aquatic vascular plants.
Polyamine Metabolism in Acanthamoeba: Polyamine Content and Synthesis of Ornithine, Putrescine, and Diaminopropane1
Authors: KIM BYEONG G. , SOBOTA ANDREZJ , BITONTI ALAN J. , McCANN PETER P. , BYERS THOMAS J. 
Published: May 2007

ABSTRACTFive polyamines which could be separated by high performance liquid chromatography were found in Acanthamoeba castellanii (strain Neff). These included in order of decreasing abundance: 1,3‐diaminopropane, spermidine, spermine, norspermidine, and putrescine. Only diaminopropane and norspermidine had been found previously. Spermine was present in cultures grown in broth, but not in defined medium. Radioactive substrates were used to establish that putrescine was synthesized by decarboxylation of ornithine, ornithine was synthesized from arginine or citrulline, and diaminopropane was synthesized from spermidine. The presence of ornithine decarboxylase (EC 4.1.1.17), arginase (EC 3.5.3.1), and urease (EC 3.5.1.5) and the absence of arginine decarboxylase (EC 4.1.1.19) were established. A scheme for polyamine biosynthesis in A. castellanii is proposed.
Further Characterization of Carbohydrate‐Containing Fractions from Trypanosoma mega1
Authors: SANTOS R. L. DOS , GORIN P. A. J. , BARRETO‐BERGTER E. 
Published: May 2007

ABSTRACTEpimastigotes of Trypanosoma mega were submitted to phenol extraction after lipid extraction, providing an extract whose carbohydrate portion (30%) contained fucose, ribose, xylose, mannose, galactose, and glucose. The purified fraction recovered in the void volume of Bio Gel P‐150 gave on SDS‐PAGE a band of Mr∼ 55,000 positive for protein and carbohydrate and a diffuse band strongly positive for carbohydrate and lipids (Mr∼ 22,000). The structural analysis of the carbohydrate moiety of this fraction by GLC‐MS indicated the presence of nonreducing end groups of fucopyranose, mannopyranose, and galactopyranose, 3‐O‐ and 4‐O‐substituted and 2,3‐ and 2,4‐di‐O‐substituted galactopyranosyl units. Extraction of this fraction with chloroform/methanol/water provided a soluble fraction that on SDS‐PAGE gave rise to a carbohydrate and lipid‐positive band (Mr∼ 22,000). This fraction contained fucose, mannose, and galactose (1:1:1). As main branch points, 2,3‐di‐O‐substituted galactopyranosyl units were present according to methylation data. Similar proportions of fucopyranosyl, mannopyranosyl, galactopyranosyl end units were present. The presence of lipids in this fraction was confirmed by methanolysis following isolation and characterization of the corresponding fatty acid methyl esters. Palmitic acid (16:0) and an 18:1 fatty acid were the predominant fatty acids.
Ichthyophthirius multifiliis (Ciliophora) Exit from Gill Epithelium1
Authors: EWING MARGARET S. , KOCAN KATHERINE M. 
Published: May 2007

ABSTRACTThe first change in the sequence of morphological events occurring as fully developed Ichthyophthirius multifiliis trophonts spontaneously left gill epithelium or as younger trophonts departed, following experimentally induced death of the fish, was the separation of parasites from overlying host cells. Discharge of contractile vacuoles may have played a role in this process. Spaces then appeared between host cells, and individual epithelial cells became vacuolated. Finally, the epithelium ruptured and the parasites swam free. In induced exit after three days residence in the host, departure of the trophont was evident only after autolysis of epithelium had occurred. Induced departure of trophonts after four days residence was more rapid, suggesting an active role for the parasite in exit. Changes in parasite and epithelium observed in induced exit were similar to those in spontaneous departure after five days residence.
Antigenic Relationship Between Plasmodium falciparum and Babesia bovis: Reactivity with Antibodies to Culture‐Derived Soluble Exoantigens1
Authors: JAMES MARK A. , MONTENEGRO‐JAMES SONIA , FAJFAR‐WHETSTONE CAROL , MONTEALEGRE FEDERICO , ERICKSON JAMES , RISTIC MIODRAG 
Published: May 2007

ABSTRACTAntigenic similarities between Plasmodium and Babesia parasites of the phylum Apicomplexa have been previously demonstrated primarily by the serological cross reactivity observed in the indirect fluorescent antibody (IFA) test. We have now studied the antigenic relationship between the human malaria parasite, Plasmodium falciparum, and the hemoparasitic agent of cattle, Babesia bovis, using rabbit monospecific antibodies produced against individual culture‐derived P. falciparum polypeptides and bovine polyspecific antibodies to B. bovis exoantigens. These respective antibodies were found to be distinctly cross reactive in the IFA test using infected erythrocytes (squirrel monkey—P. falciparum; bovine—B. bovis) as antigen substrates. Immunofluorescence was shown to be highly specific for parasite surfaces. Additionally, the degree of reactivity with soluble exoantigens contained in Plasmodium and Babesia culture supernatants was monitored by a two‐site enzyme immunoassay employing the cross‐reactive antibodies. Further evidence for antigenic cross reactivity between P. falciparum and B. bovis parasites was shown with the in vitro inhibition assay. Antibodies to P. falciparum and B. bovis were found to be highly inhibitory for the in vitro growth of P. falciparum in human erythrocytes.
Five New Species of Lagenophrys (Ciliophora, Peritricha, Lagenophryidae) from the United States with Observations on Their Developmental Stages1
Authors: CLAMP JOHN C. 
Published: May 2007

ABSTRACTFive species of the loricate genus Lagenophrys were found on freshwater hosts and are described for the first time. Lagenophrys dennisi n. sp., L. incompta n. sp., and L. oregonensis n. sp. are ectosymbionts of astacid crayfish. Lagenophrys foxi n. sp and L. missouriensis n. sp. are ectosymbionts of gammarid amphipods. All five species appear to occur only m North America. Protargol preparations of the five species reveal that the peristomial myoneme is much broader and more extensive in telotrochs and metamorphosing individuals than in adults. Darkly staining bands appearing to be somatic myonemes were also seen underneath the surface of the body and in the center of the body of telotrochs and metamorphosing individuals. The telotroch of Lagenophrys is so different from the adult that it constitutes a true larval form rather than a simple dispersal stage. Structural parallels between the telotroch of Lagenophrys and mobiline peritrichs suggest the hypothesis that mobilines evolved from the telotroch of a sessiline pentrich which had first evolved into a true larval form.