bluuebunny/crossref_metadata_2025 huggingface dataset:
In vitro Studies of Ablastin, the Reproduction‐Inhibiting Antibody to Trypanosoma lewisi*
Authors: D'ALESANDRO PHILIP A.
Published: May 2007

SYNOPSIS. Previously, the reproduction‐inhibiting effects of ablastin could only be shown in vivo. The present report describes techniques for the in vitro demonstration and titration of this antibody. With a medium composed of Hanks' balanced salt solution, rat serum, lactalbumin hydrolysate, yeast extract and rat blood lysate, blood stream forms of Trypanosoma lewisi can be grown for approximately 24 hours at 37d̀C. Starting with the medium containing normal rat serum and inoculated with adult (inhibited) trypanosomes from infected rat blood, 50% or more of the parasites are in various stages of division after incubation overnight. Under similar conditions with ablastic rat serum, the parasites do not reproduce but remain as adults. If the medium is inoculated with reproducing trypanosomes from the blood, parasites in the presence of normal serum continue to reproduce, whereas those exposed to ablastin are almost completely converted to adult, non‐reproducing forms. Similar results are obtained when the immune sera used are first adsorbed with living parasites to remove all trypanocidal antibodies. Ablastic serum inactivated at 56d̀C for 20 minutes does not lose its inhibitory activity indicating that ablastin is not complement dependent, and parasites grown on media at room temperature are not affected by the antibody suggesting that basic antigenic differences exist between blood stream forms at 37d̀C and culture forms at room temperature. Studies of the conversion of blood stream forms to culture forms indicate that the critical temperature range for the conversion lies between 28d̀ and 30d̀C. The significance of these results is discussed, and possible applications of the techniques described to studies of the mechanism of ablastic action are considered.
Comparative Excystation of Four Species of Poultry Coccidia
Authors: FARR MARION M. , DORAN DAVID J.
Published: May 2007

SYNOPSIS. Examination of the crop, gizzard, and intestinal contents of chickens fed suspensions of either Eimeria acervulina or E. tenella oocysts and turkeys fed either E. meleagrimitis or E. gallopavonis oocysts indicated that, in all 4 species, (1) oocysts apparently remained unchanged while in the crop, (2) sporocysts were liberated from oocysts while the latter were passing through the gizzard, (3) sporozoites were activated and escaped from liberated sporocysts after they had reached the small intestine, and (4) sporozoites within intact oocysts in the crop, gizzard, and intestines were not activated.

In vitro, trypsin 1–300 alone caused a small percentage of sporozoites to excyst from mechanically liberated sporocysts. The percentage of excystation increased greatly when trypsin was added to sodium taurocholate and increased even more when it was combined with chicken or turkey bile.

The two duodenal species (E. acervulina and E. meleagrimitis) differed both in vivo and in vitro from the two cecal species (E. tenella and E. gallopavonis). The duodenal species excysted in less time and farther anteriorly in the small intestine than did the cecal species. In addition, sporozoites of the two cecal species survived much longer in media containing trypsin plus bile or sodium taurccholate than did those of the two duodenal species.
Axenic Cultivation of Trichomonas tenax, the Oral Flagellate of Man I. Establishment of Cultures
Authors: DIAMOND LOUIS S. , Bartgis I. Louise
Published: May 2007

SYNOPSIS. A technique for the axenic cultivation of Trichomonas tenax, the oral flagellate of man, is presented. The medium employed consists of a nutrient broth supplemented with horse serum and a cell‐free extract of chick embryo. Three strains established in this medium have been maintained for 16, 23 and 48 months respectively.

All the cultures were initiated with trichomonads grown in association with Trypanosoma cruzi. Attempts to establish axenic cultures with trichomonads obtained from xenic cultures containing a bacterial flora of unknown composition met with failure. This suggests that the successful cutcome of the process of axenization is to a certain extent dependent upon the type of organism(s) with which T. tenax is associated in culture. Furthermore, these findings may serve to explain earlier failures since not only were all of these attempts made with media lacking tissue extract supplements but all were made using bacteria‐trichomonad cultures as a source of trichomonads.
Differentiation in Protozoa*
Authors: TRAGER WILLIAM
Published: May 2007

SYNOPSIS. Two main kinds of morphogenetic events occur among protozoa: (1) reproduction; (2) processes of reorganization, including encystment, excystment, sexual processes, structural and physiological adaptations exhibited in the course of complex life cycles, and restorative events elicited by environmental stimuli. Examples of such events are discussed with reference both to their own intrinsic interest and to their value in the study of cellular differentiation in general. Stomatogenesis in ciliates provides a remarkable instance of extensive and rapid differentiation. The phenomenon may be studied to advantage not only in reproduction but also in the macrostome‐microstome transformation. Other simple transformations in protozoa providing unparalleled material for experiments on cytodifferentiation under controlled conditions are excystment and encystment, the amebo‐flagellate transformation, and the leishmania‐leptomonad change. The more complex transformations occurring in the life cycles of trypanosomes and in the appearance of sex under the influence of an insect hormone provide additional material of basic significance to an understanding of differentiation.
Distribution of Schizonts of Plasmodium berghei in Tissues of Rats, Mice and Hamsters*
Authors: ALGER NELDA E.
Published: May 2007

SYNOPSIS. Adult mice, adult hamsters, 22‐day‐old rats, and 240–250 gram rats were each infected with one million parasitized red cells. Significant differences in the distribution of schizonts in the tissues of the four groups of animals ranked from the lowest to the highest were found to be as follows: young rats—blood, spleen, liver, bone marrow; older rats—blood, liver, spleen, bone marrow; adult mice—no significant difference between blood and liver, next in rank bone marrow, spleen; hamster—blood, but no significant differences among the organs.
Polymorphic Properties of Tetrahymena patula During Growth in Axenic Culture*
Authors: STONE G. E.
Published: May 2007

SYNOPSIS. The effects of temperature and pH on growth and polymorphism were studied. The dimorphic condition followed a cyclic nature associated with growth in axenic culture. During logarithmic growth the population consisted of 95–100% microstomes. Upon entering stationary phase the microstomes transformed into macrostomes. The percent microstomes which transformed into macrostomes was found to be affected by culture conditions. When grown at 25°C, pH 7.0, 50% of the population during stationary phase was macrostomes, whereas cultures grown at 25°, pH 7.4, showed 26% macrostomes during stationary phase. Hydrogen ion concentrations higher and lower than this value produced increasingly larger percent of macrostomes during stationary phase. At 20°C, pH 7.0, stationary phase, the population consisted of 100% macrostomes. Generally, those conditions which favored growth in axenic culture also favored the microstome during stationary phase.

Large populations of microstomes were induced to transform into macrostomes by transferring a logarithmically growing culture from 25° to 20° or 15°C. Silver impregnated cells showed that the transformation from microstome to macrostome involved oral replacement.

It was found that macrostomes, when placed in fresh medium, gave rise to two microstomes through cell division. A direct transformation from macrostome to microstome was not observed.
Metabolism of Purines by Extracts of Tetrahymena*
Authors: SEAMAN GERALD R.
Published: May 2007

SYNOPSIS. Cell‐free extracts of Tetrahymena contain adenase, guanase, xanthine oxidase, uricase, and adenosine deaminase. The levels of activity of the latter three are of the same order of magnitude as in mammalian tissues. 5′‐Adenylic acid deaminase is also present in ciliate extracts. Spectrophotometric assays of this enzyme indicate formation of two intermediates which, although not as yet identified, are not precursors of uric acid, the expected product of deamination of the nucleotide.
Extrinsic Requirements for Encystation by the Soil Amoeba, Hartmannella rhysodes*
Authors: BAND R. NEAL
Published: May 2007

SYNOPSIS. The environmental factors causing encystation in Hartmannella rhysodes, a small soil amoeba, appear to be an elevated osmotic pressure, Ca2+ and Mg2+, aeration and a decrease in carbon sources. After 36 hr under these conditions, amoebae harvested during active growth encyst. Nutrients essential for growth, other than carbon sources, have no effect on encystation. The factors which bring about encystation are components of the defined medium, in which the minimum essential organic requirements for growth are known.
A Bacterial Endosymbiote inCrithidia (Strigomonas) oncopelti:Biochemical and Morphological Aspects*
Authors: GILL JAMES W. , VOGEL HENRY J.
Published: May 2007

SYNOPSIS.It is concluded that the trypanosomatid flagellate,Crithidia (Strigomonas, Herpetomonas, Lepiomonas) oncopelti, contains a bacterial endosymbiote, which provides the protozoon with biosynthetic capabilities and, hence, with a measure of nutritional independence; the protozoon in turn gives the endosymbiote the protection of an intracellular environment. Tracer experiments show thatC. oncopeltihas the “bacterial” kind of lysine pathway (via α,ε‐diaminopimelic acid). Diaminopimelic decarboxylase, the last enzyme in this pathway, is associated with the endosymbiote. Electron micrographs of the endosymbiote reveal structures consistent with a cytoplasmic membrane and a cell wall. Endosymbiotes that are dividing, as judged by the presence of a constriction, exhibit membrane septa. Additionally, there are zones that are interpreted as representing nuclear material. The protozoon is “cured” of the endosymbiote by treatment with penicillin in a complex medium. The absence of the endosymbiote from “cured” protozoa can be checked with a staining method that permits the reliable detection of the endosymbiote in untreated protozoa.
The Inheritance of H‐L Serotype Differences at Conjugation in Tetrahymena*
Authors: NANNEY D. L.
Published: May 2007

SYNOPSIS. Cells of variety 1, Tetrahymena pyriformis, manifest different immobilization antigens when grown at 15d̀ and 25d̀C. These differences are partially maintained for a period of growth at an intermediate temperature. Crosses were performed at intermediate temperatures between parental cultures conditioned to high and low temperatures and the antigenic characteristics of their progeny were determined. When conjugation is abortive and paired cells do not complete conjugation, the cells separate and produce clones with distinctive serotypes. When conjugation is completed, however, no systematic differences between exconjugants can be demonstrated. These results differ from those obtained under comparable circumstances in Paramecium aurelia, and fail to support the idea that the cytoplasm plays a significant role in the maintenance of serotypes in Tetrahymena.
Electron Microscopy of Astasia longa*
Authors: RINGO DAVID L.
Published: May 2007

SYNOPSIS. Cells of Astasia longa (Jahn) were grown on a simple defined medium, fixed in the stationary phase of growth with OsO4, stained with uranyl acetate, and embedded in Vestopal for electron microscopy. The cell wall was found to be a membranous structure 100 Å thick. A double nuclear membrane, nucleolus, and many darkly staining bodies were observed in the nucleus. Cells contained ribosomes and elaborate Golgi bodies, but no well developed endoplasmic reticulum. The numerous mitochondria typically had well‐defined cristae running longitudinally in the mitochondrion. Two bodies of unknown function were observed, one sometimes seen to surround mitochondria, the other bounded by a double membrane. A model of the reservoir structure of the euglenoids is presented, based on observations of the reservoir of A. longa and on published data from Euglena gracilis and E. viridis.
Variation of Cell and Nuclear Volume of Tetrahymena pyriformis with Three Parameters of Growth: Age of Culture, Age of Cell, and Generation Time*
Authors: SUMMERS L. G.
Published: May 2007

SYNOPSIS. Cell volume and nuclear volume of Tetrahymena pyriformis strains HS and E, grown on a defined medium, were measured as a function of age of culture, age of cell and generation time. The volume of an “average” single cell between divisions was calculated for logarithmic phase cultures by using volume distributions and difference equations. Cell volume measurements were made by compressing the cells to known thickness and measuring the area from photomicrographs. The nuclear volume was determined from diameter measurements of the nucleus by assuming the shape of a sphere.

The cell volume decreased from the lag phase to the logarithmic phase and reached a minimum at the end of the logarithmic phase. It increased again during the stationary phase. The nuclear volume also decreased from the lag to logarithmic phase, but continued to decrease in the stationary phase until it reached the nuclear volume of the daughter cell. The average single cell volume increased at a constant rate for 85% of the generation time, at which point the rate diminished to zero. The nuclear volume showed no increase until 35% of the generation time had passed. It then increased at an accelerated rate which diminished just before division. Both the average cell and nuclear volumes decreased with increase in temperature until the optimum temperature was reached, at which point they increased again. There were no appreciable differences in volume changes for cells grown on different media.
The Development and Survival of the Blood‐Stream Forms of Trypanosoma conorhini in Culture
Authors: DESOWITZ R. S.
Published: May 2007

SYNOPSIS. Trypanosoma conorhini has been isolated from infected Triatoma rubrofasciata in Singapore. Parasites derived from the triatomid gut were inoculated into NNN medium and some cultures maintained at 25° to 27°C while others were kept at 37°. In cultures kept at lower temperatures crithidial forms predominated; however, at 37° blood‐stream trypanosome forms developed and survived for 10 days or more.
In vivo Activity of L‐Azaserine Against Trypanosoma equiperdum*
Authors: JAFFE JULIAN J.
Published: May 2007

SYNOPSIS. When the antibiotic L‐azaserine was injected intraperitoneally into female Ha/ICR albino mice infected with T. equiperdum, a marked but temporary inhibition of trypanosomal reproduction was observed and survival time of the hosts was more than doubled. The efficacy cf a given dose of azaserine was considerably reduced when its equivalent was divided equally over a 5‐day period. Azaserine was much more effective when injected intraperitoneally than when given by gastric intubation, even though measures were taken in the latter circumstance to reduce the rate of degradation of the drug by gastric juice and the liver. Some purine analogs were tested in combination with azaserine for ability to prolong the lives of mice infected with T. equiperdum; 6‐mercaptopurine was the only one that significantly enhanced the efficacy of azaserine. Evidence is presented that azaserine inhibits trypanosomal reproduction directly rather than by a host‐mediated mechanism.
A New Species of Leptomonas Parasitizing the Macronucleus of Paramecium trichium*
Authors: GILLIES CONCETTINA , HANSON EARL D.
Published: May 2007

SYNOPSIS. A leptomonad zooflagellate infecting the macronucleus of Paramecium trichium is described. The cell body of Leptomonas karyophilus n. sp. is 5μ long and the flagellum is 12μ long. There is a central ovoid nucleus, a bar‐shaped kinetoplast and a contractile vacuole. The flagellate undergoes division in the macronucleus, proliferating there until it has killed its host. Mildly infected paramecia are able to divide and if fed regularly can be maintained carrying the parasite. Cross infections with P. caudatum, P. bursaria and P. aurelia were successful to varying degrees.
A Comparison of the Protein Composition of Three Species of Amoebae*
Authors: Kates Joseph R. , Goldstein Lester
Published: May 2007

SYNOPSIS. A comparison has been made of the characteristics of proteins present in two strains of Amoeba proteus, Amoeba discoides, and Chaos chaos. Extractable protein mixtures of each of the strains have been compared with respect to electrophoretic mobilities, enzyme activities, and immunological reactivities. With one slight exception, the three Amoeba strains appear to be identical by all the tests that have been performed but each of the three strains is dearly different from C. chaos by the same tests. The exception may be a difference of a single immunologically active component between A. discoides and one of the A. proteus strains, according to a preliminary observation.
Physiology of an Obligate Photoautotroph (Chlamydomonas moewusii) I. Characteristics of Synchronously and Randomly Reproducing Cells and an Hypothesis to Explain Their Population Curves*
Authors: Bernstein Emil
Published: May 2007

SYNOPSIS. Cultures of Chlamydomonas moewusii begun with log‐phase cells of any age had the same lag phases and showed slight but demonstrable synchronous division. Those begun with stationary‐phase cells had longer lag phases and showed pronounced synchronously reproductive tendencies. Cultures grown under favorable or unfavorable conditions, and their log‐phase cells compared, behaved like log‐ and stationary‐phase cells respectively. Both stationary phase and unfavorably grown cultures shared some of the characteristics of cultures synchronized by light‐dark cycling. A light‐dark cycled population divides synchronously in direct response to the cycle, and not as a result of being transferred from one medium to another. Synchronous division will occur as 8‐fold increases with initial cell densities as low as 10 cells/ml and as high as 100,000 cells/ml. Initial concentrations above 100,000/ml will result in synchronous bursts of less than 8 times the cell number. Cycled cells will continue to divide synchronously when exposed to continuous illumination for an additional 24 hr (i.e., 1 entire “cycle” period). After 12 more hr, they divide exponentially. Continuously illuminated young log cells when subjected to a light‐dark regimen begin growing and dividing synchronously by the end of the 1st 12‐hr dark period (i.e., during the 2nd 24‐hr cycle). The synchronized cell cycle is described cytologkally and quantitatively, and the degree of synchrony for each of the phases of the cell cycle analyzed. After comparing the data from the synchronously and randomly growing cultures, an hypothesis is suggested to explain exponential and synchronous growth and division.
Metabolism of Schizotrypanum cruzi Chagas. IV. Evidence in Favor of the Presence of a Hexokinase*
Authors: Warren L. G. , Guevara A.
Published: May 2007

SYNOPSIS. Glucose‐6‐phosphate and adenosine triphospbate levels in glucose‐abundant and glucose‐depleted preparations of the culture forms of Schizotrypanum cruzi were measured. Glucose‐6‐phosphatc formation was dependent upon an exogenous source of glucose. Adenosine triphosphate levels were maintained whether exogenous glucose was present or absent. Net synthesis of adenosine triphosphate in the presence of exogenous glucose was observed. The results favor the presence of a hexokinase in S. cruzi.
Phosphate, Purines and Pyrimidines as Excretory Products of Tetrahymena*
Authors: LEBOY PHOEBE S. , OLINE SYLVIA G. , CONNER ROBERT L.
Published: May 2007

SYNOPSIS. Tetrahymena pyriformis strain W, incubated for 3 hours in a salts‐PO4 medium, showed a net loss of phosphate from the cell. This loss of phosphate was accompanied by release of material having an absorption maximum at 250–260 nvi. The u.v.‐absorbing material contained hypoxanthine as well as a pyrimidine component.

The release of hypoxanthine was consistent with an absence of detectable xanthine oxidase activity in Tetrahymena homogenates. Studies with homogenates indicated that hypoxanthine formation was paralleled by the formation of perchloric acid‐soluble material absorbing at 250 mμ, suggesting the degradation of nucleic acid.

While glucose diminished the extent of phosphate and hypoxanthine loss from intact cells, the addition of iodoacetic acid (IAA) resulted in increased losses, as well as release of pentose into the medium. Since IAA did not influence the amount of acid‐soluble material formed by homogenates, it is suggested that the effects of glucose and IAA on the extent of excretion represent alterations in the ability of the cells to utilize nucleic acid degradation products in RXA synthesis.
The Contractile Vacuole and Related Structures in Tetrahymena pyriformis*
Authors: ELLIOTT ALFRED M. , BAK IL JIN
Published: May 2007

SYNOPSIS. The nephridial system of T. pyriformis consists of a contractile vacuole with its two pores and an elaborate network of tubules. Both the vacuole and its tubules constitute a continuous system of single membranes of approximately 70 Å in thickness. Tubular fibrils of about 250 Å extend from the pore wall to the vacuole membrane and appear to function in dilating the pore prior to systole. The nephridial tubules arise directly from the wall of the vacuole and are continuous with it throughout the vacuolar cycle. The tubules appear to be contiguous with the granular endoplasmic reticulum. A typical Golgi complex was not found. Some speculation about the interrelation of these structures as regards function is offered.
The Mechanism of Locomotion of Flagellates. II. Function of the Mastigonemes of Ochromonas*
Authors: JAHN THEODORE L. , LANOMAN MICHAEL D. , FONSECA JAMES R.
Published: May 2007

SYNOPSIS. Mastigonemes occur on flagella of many species of Protozoa, but the only function so far proposed for the mastigonemes is to increase the effective surface of the flagellum. Locomotion of Ochromonas malhamensis, O. danica, and an unidentified marine chrysomonad was examined by means of high speed microcinematography up to 600 pictures per second. In addition, analyses were performed on the movement of the organism in a suspension of polystyrene spheres (1.17 μ in diameter). The films clearly show that the organisms move by means of a planar sine wave in the long anteriorly‐directed flagellum. The wave starts at the basal end of the flagellum and progresses distally. It is apparent that the organisms are pulled forward by the action of the long flagellum, and that the flagellum does not push backward as would ordinarily be expected with a forwardly‐directed sine wave.

It is well known that flagellar sine waves usually start at the base, move distally, and produce a push toward the point of attachment. It also is known (2) that in Mastigamoeba a helical wave may start at the tip, progress proximally toward the base, and pull the organism. However, in the present organisms the wave begins at the base, moves distally (i.e., forward), and pulls the organism. The flagellum is a true tractellum. The theoretical calculations of Taylor (1952, Proc. Roy. Soc., 214A, 158) show that if a thin cylinder, undergoing sinuous movements produced by a traveling sine wave of active bending, has a roughness of surface which is sufficiently great and has a certain directional character, propulsion may be achieved in the direction opposite to that expected of a smooth cylinder bending in exactly the same manner. It is known that the long flagellum of the chrysomonads is pantonematic, i.e., has numerous stiff lateral mastigonemes on at least two and probably all sides. It is proposed that one function of these mastigonemes is to provide a roughness of surface which brings about this type of reversal.
Quantitative Studies of Metabolism in Phagotrophic Ciliates. I. Growth of Tetrahymena pyriformis W on Viable and on Killed Bacteria*
Authors: DUCOFF H. S. , WILLIAMS SISTER M. , SYN TOH BEE , BUTLER BARBARA D.
Published: May 2007

SYNOPSIS. Tetrahymena pyriformis W, transferred from proteose peptone to bacterized Cerophyl, exhibited the same growth rate whether A. aerogenes, E. coli, or S. marcescens was the food organism. When T. pyriformis was suspended in sterile Cerophyl and fed various amounts of killed bacteria, the initial growth rate was the same as when viable bacteria were used, and the total increase in ciliate population was a function of the amount of bacterial protoplasm added. With Cerophyl concentrations below 0.1%, ingestion of the bacteria and reproduction of the ciliates were greatly reduced, suggesting a phagotrophy‐inducing factor in the Cerophyl. T. pyriformis resuspended in sterile Cerophyl can be fed washed killed bacteria for studies on various aspects of the metabolism of phagotrophic ciliates.
Morphogenesis in the Hymenostome Ciliate Pseudocohnilembus persalinus and its Taxonomic and Phylogenetic Implications*
Authors: EVANS FREDERICK R. , CORLISS JOHN O.
Published: May 2007

SYNOPSIS. Morphogenesis in the small holotrich ciliate Pseudocohnilembus persalinus has been found to be more complex than that reported to date for any other hymenostome species, at least with respect to the major phenomenon of stomatogenesis. Formation of two anlagen or fields of proliferating kinetosomes in the vicinity of the old oral area initiates the highly autonomous process. Subsequently a number of separate but coordinated morphogenetic movements occur which involve not only the new anlagen and their extraordinary growth and fragmentation but also the bases of the “old” ciliary buccal organelles.

Particularly indispensable in our investigation was the Bodian protargol technique which reveals the external ciliature of a properly fixed organism as well as components of its infraciliature. The Chatton‐Lwoff silver impregnation method, however, was also very useful in the overall comparative study of the present and related species of ciliates.

At one stage in stomatogenesis of Pseudocohnilembus persalinus there is clear evidence of a basic tetrahymenal plan of organization of the buccal ciliature, even though this is not at all apparent in the mature, non‐dividing ciliate. Such a revelation underlines the significant value of morphogenetic studies in comparative ciliate systematics, for our findings permit retention of the genus Pseudocohnilembus in the suborder Tetrahymenina of the holotrich order Hymenostomatida. At the same time, however, they necessitate revision of some currently held concepts in the fields of ciliate morphology, taxonomy, and phylogeny.
Tetrahymena pyriformis from Several Pacific Islands and Australia*
Authors: ELLIOTT ALFRED M. , STUDIER MARGARET A. , WORK JANIS A.
Published: May 2007

SYNOPSIS. From a total of 223 diverse habitats located in Australia, New Zealand, Fiji, Hawaii, Japan, Hong Kong, and the Philippines, 144 yielded Tetrahymena pyriformis. These collections were taken from a latitude of 35° N. to 35° S., from sea level to 4500 feet, and temperatures ranging from 15° to 30°C. From these habitats 2300 clones were isolated, of which approximately 800 were examined for micronuclei and 450 tested for mating type.

Two distinct interbreeding populations were isolated from the Australian collections. They failed to mate with any of the 10 known varieties and are therefore designated as varieties 11 and 12. No sexually active clones were found in New Zealand, Japan or Hong Kong. However, clones belonging to variety 9, previously found only in Colombia and Panama, were isolated from habitats in Hawaii and Fiji. This evidence suggests that possibly variety 9 is confined primarily to the tropics. There seems to be no other correlation of varieties with land mass.

Representative clones from each habitat were established in axenic culture, all of which grew well in proteose‐peptone. When first tested, a number of mutants were found among the 66 clones screened for their nutritional requirements. Some grew without thioctic acid or niacin. Several required aspaitic acid and one required biotin and proline in addition to the 18 nutrilites required for strain E. No pattern could be found which related the mutants to a particular region. Examination of the mutants one year later revealed that the synthetic capacity for both niacin and thioctic acid had been lost and that those clones requiring aspartic acid had acquired the capacity to make the amino acid.
An Occurrence of Shepheardella Siddal (Foraminiferida) from the West Coast of North America
Authors: DOUGLAS ROBERT
Published: May 2007

SYNOPSIS. An occurrence of the allogromid genus Shepheardella is here reported for the first time from the western hemisphere. The foraminifer is briefly redescribed and illustrated.
Iron Deficiency and the Metabolism of Tetrahymena pyriformis*
Authors: CONNER R. L. , CLINE S. G.
Published: May 2007

SYNOPSIS. An iron deficiency was noted for Tetrahymena grown in a proteose‐peptone‐yeast extract medium. Thus, the addition of an iron chelate and glucose was found to give consistent and luxuriant growth, whereas a number of other additives, including sodium acetate, an inorganic salt mixture lacking iron, and vitamins were found to be without influence on growth rate or cellular yield.

Iron‐deficient cells showed a marked reduction of oxidative capacity when suspended in a non‐nutrient medium as well as when supplied with oxidizable substrates. A 1 hour incubation of iron‐deficient Tetrahymena with iron chelate restored oxidative capacity only when the cells were suspended in a nutrient (peptone) medium. Growth of Tetrahymena in media autoclaved with salts resulted in cells with a larger volume but with no increase in oxidative capacity.

The addition of 2,4‐dinitrophenol elevated respiration of cells suspended in a non‐nutrient medium, and of iron deficient cells suspended in the growth medium, suggesting that this compound increases the availability of iron or iron containing compounds, or by‐passes the limiting steps.

Respiratory quotients were lowered by an iron deficiency and elevated when the cells were grown in the presence of iron and glucose. This suggests more complete utilization of the carbohydrate, possibly due to the activity of a number of enzymes known to be iron‐containing metalloproteins that are required for oxidative glucose dissimilation.
Leptomonas mirabilis Roubaud 1908 in a Central American Blowfly*
Authors: WALLACE F. G. , TODD S. RAMMOHAN
Published: May 2007

SYNOPSIS. The isolation of a culture of Leptomonas mirabilis from the fly Cynomyopsis cadaverina from Guatemala shows that this flagellate is not a stage of Herpetomonas muscarum. It is characterized by giant forms that reach 200 μ in length.

All records of giant leptomonads from flies are reviewed. This species was established in culture only by the addition of mosquito extract to the medium. Division of the giant flagellates appears to occur by equal binary fission.
Isospora spilogales n. sp. and I. sengeri n. sp. (Protozoa: Eimeriidae) from the Spotted Skunk, Spilogale putorius ambarvalis
Authors: LEVINE NORMAN D. , IVENS VIRGINIA
Published: May 2007

SYNOPSIS. Two new species of Isospora are described from the feces of an eastern spotted skunk Spilogale putorius ambarvalis imported into Montana from Florida. The oocysts of I. spilogales n. sp. are 29 to 38 by 22 to 28 μ and contain 2 sporocysts measuring 17 to 22 by 13 to 16 μ; a few Caryospora‐like oocysts containing a single sporocyst were considered abnormal I. spilogales oocysts. The oocysts of I. sengeri n. sp. are 16 to 23 by 12 to 18 μ and contain 2 sporocysts measuring 10 to 14 by 8 to 12 μ.
Comparative Metabolism of C14‐Glucose in Two Strains of Trypanosoma cruzi*
Authors: MANCILLA R. , NAQUIRA G.
Published: May 2007

SYNOPSIS. The Tulahuen and Peruvian strains of Trypanosoma cruzi have been compared as to their ability to metabolize C14‐glucose uniformly labeled, or labeled in carbons 1, 2, or 6. Most of the radioactivity from uniformly labeled glucose is incorporated into organic acids in both strains, but significant radioactivity is also recovered in CO2. The Tulahuen strain has a slightly higher rate of glucose consumption, and the rate of incorporation of uniformly labeled glucose‐C14 into CO2 is also higher. More radioactivity is incorporated into proteins from uniformly labeled glucose‐C14 in the Tulahuen strain, but the radioactivity recovered in total organic acids is fairly similar in both cases. On the basis of the rates of C14O2 production from C14‐glucose specifically labeled in carbons 1, 2, or 6, as well as the rates of incorporation into glycerol from uniformly labeled C14‐glucose and glucose‐6‐C14, it is considered that the reactions of the pentose phosphate pathway play a more important role in the Tulahuen strain. The pentose phosphate pathway accounts for 41.4% of the glucose catabolized by the Tulahuen strain compared to only 27.9% in the Peruvian strain. It is suggested that differences in the participation of alternative pathways of carbohydrate metabolism may have some relationship to pathogenicity.
Morphogenesis and Division in Chains of Tetrahymena pyriformis GL*
Authors: FRANKEL JOSEPH
Published: May 2007

SYNOPSIS. The formation of chains was induced both in exponentially growing and in synchronized cultures of Tetrahymena Pyriformis GL, by application of one or two hr 34°C shocks. An arrest in constriction along the division furrow is brought about as a result of prolonged exposure to 34° during an early phase of cell division.

After return to optimal temperatures, the chains remain in their original tandem configuration. They possess two sets of cortical structures, and generally also two macronuclei.

Subsequently, two new oral primordia appear, one in each component. These primordia develop in synchrony with each other. The later development of the chains is correlated with the placement of the oral primordia. In some situations, these primordia form immediately posterior to the pre‐existing oral areas and replace them; in these cases, the original division furrow is obliterated, and irregular and probably unstable homopolar doublets form. More frequently, one or both of the oral primordia are normal division primordia. In these cases, the original oral area of the anterior component persists, while that of the posterior component is resorbed. The original fission line persists, and two new fission lines are formed anterior to each of the new oral primordia. When constriction takes place along the new fission lines, the original arrested fission line is occasionally reactivated, and the chain then divides into four cells. More often, the original furrow is not reactivated (or only incompletely reactivated), and the chain divides into two or three cells, depending on how close the two new division furrows are to each other.

The chains ultimately give rise to normal clones of singlet cells. No clones of doublets were observed.

In the Discussion, the synchronization of developmental events in the two components of the chain is emphasized. The cases of reactivation of the original fission line in synchrony with constriction along the newly formed fission lines seem to indicate that furrowing results from an interaction of a preformed cortical site (fission line) with a pervasive substance which acts to trigger constriction.
Factors Influencing the in vitro Culture of the Rumen Ciliate Ophryoscolex purkynei Stein
Authors: MAH ROBERT A.
Published: May 2007

SYNOPSIS. A method for the in vitro culture of O. purkynei was developed which permitted the continuous culture of this protozoon in clone culture for a. period of 32 months. The shortest division time was 24 hr. The concentration of cells varied between 700 and 1000/ml in the routine procedure. Variations in spination which occurred in the clone culture suggested that this characteristic was of doubtful taxonomic importance.

Ground wheat and alfalfa served as substrates but soluble sugars did not. Green plant material appeared to be necessary for continued growth of the protozoa. Ingestion of a large streptococcus was demonstrated by vital staining of a mixed population of bacteria with tetrazolium prior to incubation with the protozoan suspension in the presence of wheat.

O. purkynei can tolerate exposure to variations in osmotic pressure, temperature, and oxygen which are consonant with its transfer in nature by grooming or ingestion of contaminated food or drink.
Comparison of the Life Cycle of Leptomonas oncopelti and Phytomonas elmassiani*
Authors: MCGHEE R. BARCLAY , HANSON WILLIAM L.
Published: May 2007

SYNOPSIS. After several years of field work devoted primarily to determining the incidence of infection of the common milkweed Asclepias syriaca with the trypanosomatid Phytomonas elmassiani, the life cycle of this parasite was determined under controlled conditions. Upon ingestion of phytomonads by the bug Oncopeltus fasciatus, reproduction apparently ceases but growth of individual phytomonads continues until they assume relatively giant proportions. Ten days after ingestion, giant forms are found in the hemocoel of the bug and by 12 days similar forms are present in the salivary glands. In this latter organ, unequal fission takes place with the ultimate formation of numerous forms similar to those found in the plant. Within 2 weeks after these infected bugs had fed on milkweeds, parasites were detected in the latex of formerly non‐parasitized plants. The lack of reproduction in the alimentary tract, the formation of giant forms, and the migration through the hemocoel to the salivary glands contrast markedly with the development of Leptomonas oncoptlti in the same bug. In the latter organism, budding leads to the formation of leishmaniform organisms which pass out with feces and are presumably the infective stage of the leptomonad.
Relations Between Temperature Sensitivity and Morphogenesis in Tetrahymena pyriformis GL*
Authors: WILLIAMS NORMAN E.
Published: May 2007

SYNOPSIS. The division delay responses of Tetrahymena (“set‐back” curves) which result from heat shocks of the type used in synchronizing studies have been examined in logarithmic and synchronized T. pyriformis GL. The curves indicate an increasing sensitivity to heat shocks with increasing cell age, a sudden sharp increase just prior to the “transition point” and a loss of sensitivity at the transition point. A correlated study of morphogenesis in the synchronous generation suggests that the sudden increase in thermal sensitivity before the transition point is due to a dedifferentiation and redifferentiation of the developing oral primordium which can be induced at this time. The results also suggest that the “stabilization” of the primordium which follows the transition point may occur at more than one developmental stage, i.e., is not stage‐specific. It is suggested that stabilization may therefore be due to conditions lying outside the primordium.
Some Observations on the Structure of the Peristomial Membranelle of Spirostomum ambiguum
Authors: DANIEL WENDELL A. , MATTERN CARL F. T.
Published: May 2007

SYNOPSIS. Electron‐microscopic observations of Spirostomum ambiguum have demonstrated additional details of superficial and deep tubular connections with peristomial and somatic kinetosomes. The superficial peristomial tubules appear to connect adjacent rows of kinetosomes. Anatomically, they course distally from the proximal kinetosomal plate. The deep tubules run proximally from the kinetosomal plate. Those in the somatic region appear to enter the endoplasm; those in the peristomial region leave the kinetosome as bundles of either 10 or 11 tubules which steadily converge to form 2 compact rows of 10 tubular bundles. These tubules connect to 2 of the 3 rows of 10 cilia each, the rows of 3 being separated by membranous folds protruding perpendicular to the peristomial groove. The rows of bundles converge further, enter the endoplasm and fan out again into tubular sheets, some of which appear to course in an antero‐posterior direction. Another set of tubules arises from each of the kinetosomes in the 3rd row of 10 kinetosomes and courses proximally at a different angle from those arising from the 2 other kinetosome rows. Terminations have not been observed for the deep somatic or peristomial tubules. Their possible role in producing the forceful longitudinal contraction of Spirostomum is discussed.
Fine Structure of Developing and Mature Trichocysts in Frontonia vesiculosa*
Authors: YUSA AYERE
Published: May 2007

SYNOPSIS. An electron microscope study of regenerating trichocysts in Frontonia vesirztlosa showed that these organelles oripnate from primordial, membrane‐limited vesicles which appear randomly in the endoplasm. The characteristic pattern of development leading to the first definitive organization of the trichocyst involves the elaboration of the amorphous intravesicular substance into a series of closely packed fibrous sheets. These densely staining elements, laid down in two dimensional arrays, constitute the fundamental plan upon which the various structural subdivisions of the organelle are subsequently formed. Maturation involves, however, the re‐transformation of the distinctly fibrillar pattern of the body into a homogeneous, structureless matrix.

The mature trichocyst, consisting of the tip, cap and body, is a pyriform structure bounded by a thin external membrane which is continuous with the pellicle. Extrusion of the organelle results in the transformation of the homogeneous tip and body into a slender shaft with transverse striations having a familiar periodicity of about 560 Å. During discharge the entire organelle is ejected, but the cap does not participate in the formation of the shaft. Elementary units of 120Å and 250 Å periodicities are also described in intracellularly discharged trichocysts. These observations are discussed in relation to current theories on the nature of the extrusion process.

The endoplasmic origin of trichocysts in Frontonia does not support the classical theory of the morphogenetic pluripatency of kinetosomes insofar as i t relates to the direct derivation of these organelles from pre‐existing ciliary basal bodies.
Nosema muris n. sp., a New Microsporidian Parasite of the White Mouse (Mus musculus L.)
Authors: WEISER JAROSLAV
Published: May 2007

SYNOPSIS. A microsporidian, Nosema muris n. sp., is described from laboratory white mice in Czechoslovakia. I t differs from Nosema cuniculi (Levaditi, Nicolau and Schoen, 1923) and other Microsporidia in mice in that it develops in the omentum and heart muscle, iorming large masses of schizonts and spores. The parasite is distributed to other tissues (liver, spleen, fat, peritoneal muscles, connective tissue and brain) by infected mononudear cells, and then forms localized cysts in them. Kidney, lungs, adrenal glands, pancreas and salivary glands are not infected. The parasite can be transmitted via the placenta, by feeding on infected tissues, or by experimental injection of ascitic fluid.
Inhibition by Chloramphenicol of Chlorophyll and Protein Synthesis and Growth in Euglena gracilis
Authors: POGO BEATRIZ G. T. , POGO ANGEL O.
Published: May 2007

SYNOPSIS. Chloramphenicol inhibits growth of Euglena gracilis. It also interferes in the “greening” process by inhibiting protein synthesis (measured by leucine uptake), but RNA synthesis is essentially unafiected. The antibiotic acts on all cell fractions, but prefermtially inhibits the synthesis of plastid protein. Inhibition of chlorophyll synthesis is transitory and does not affect the self‐reproduction system for chloroplast formation.
Susceptibility of 1‐ and 3‐Day‐Old Chicks to Infection with the Coccidium, Eimeria acervulina
Authors: DORAN DAVID J. , FARR MARION M.
Published: May 2007

SYNOPSIS. One‐day‐old chicks were less susceptible to experimental infection with E. acervidina than were 3‐day‐old chicks. Chicks fed intact oocysts when 3 days old produced 5.3, 6.7, and 42.7 times as many oocysts and had more extensive lesions than did those fed a similar number of oocysts when 1 day old. When oocyst suspensions that contained both liberated sporocysts and intact oocysts were administered, chicks infected when 3 days old produced only 1.8, 1.3, and 2.6 times as many oocysts as did those infected when 1 day old.

Examination of gizzard and intestinal contents of chicks killed 2–1½ hr after receiving massive numbers of intact oocysts showed that only a few sporocysts were liberated from oocysts in the gizzard of 1‐day‐old chicks, whereas more were liberated in the gizzard of 3‐day‐old chicks. Very few sporozoites were found in the duodenum of the 1‐day‐old chicks. but there was a linear increase in the percentages in samples from lower levels of the small intestine. In 3‐day‐old chicks, excystation in the duodenum was high and, instead of increasing, remained at about the same level in the jejunum.

The far smaller number of liberated sporocysts in the gizzards of 1‐day‐old chicks is attributed to less musculature and an incompletely developed grinding surface The delayed excystation of sporozoites in the intestine of 1‐day‐old chicks is thought to be due to suboptimal concentrations of trypsin and/or other pancreatic enzymes effecting excystation.

The lighter infections observed in 1‐day‐old chicks, as compared to those in chicks 3 days old, are attributed to (a) a smaller number of liberated sporocysts leaving the gizzard, (b) delayed excystation in the intestine, and (c) less opportunity for sporozoites to penetrate epithelial cells.
Biochemical Studies on Irradiated Protozoa. II. The Deamination of Deoxycytidine and Deoxycytidylic Acid by Tetrahymena pyriformis W*
Authors: WINICUR SANDRA , ROTH JAY S.
Published: May 2007

SYNOPSIS. The high speed supernatant fraction obtained from cell‐free preparations of Tetrahymena pyriformis W contains an enzyme that deaminates deoxycytidine (dC) readily, but there is no evidence for a specific dCMP deaminase. The supernatant fraction also contains an active dCMP phosphatase which is inhibited by high phosphate concentration. dC deaminase in declining order deaminates BrdC, IdC, dC, MedC and dCMP. The enzyme does not appear to have a cofactor and is unaffected by Mg† and EDTA. It exhibits a broad pH optimum. Irradiation with 570,000 r of γ‐rays did not markedly affect the activity of dC, dG or dA deamination by Tetrahymena high speed supernatant fraction.
Preparation of Fatty Acids Labeled with C14 from Ochromonas danica*
Authors: GELLERMAN J. L. , SCHLENK H.
Published: May 2007

SYNOPSIS. Labeled fatty acids were produced by adding 10 mc acetate‐1,2‐C14 to cultures of Ochrosonas danica, with a recovery of 21.4% of the radioactivity as mixed methyl esters.

Individual esters, or mixtures of isomers, were isolated in amounts between 2 and 200 mg by liquid‐liquid chromatography followed by gas‐liquid chromatography. Several esters, including Δ8,11,14‐C20, Δ5,8,11,14,17‐C20, Δ7,10,13,16‐C22 and Δ4,7,10,13,18‐C22 were obtained pure. Linoleate and arachidonate contained not more than 4% isomers; isomerism was more pronounced with C18:3 and C20:2.

The effect of different culturing conditions on fatty acid yield, composition and incorporation of C14 was explored. The radioactive level of acids from the preparative run varied within a factor of 3, the average being about 1 μc/mg.

All analytical and preparative procedures are described in detail and discussed.