bluuebunny/crossref_metadata_2025_split huggingface dataset:
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.
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.
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.
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.
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.
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.
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.
The Effects of Heat and Cold on Cellular Development in Synchronized Tetrahymena pyriformis WH‐6*
Authors: GAVIN RAY H. 
Published: May 2007

SYNOPSIS. Experiments were performed to ascertain the effect of heat and cold on oral and micronuclear development in synchronized Tetrahymena pyriformis WH‐6. The developing oral primordium becomes insensitive to cold sometime during stage 2. Cold shocks cause the reversion of many stage 2 primordia to stage 1. Cells so affected are set back in division. The delayed division is always asynchronous. When heat shocks are applied prior to late stage 4, the developing primordium will regress. High temperature shocks applied at later stages permit continued development. However, when the cell begins to cleave at the high temperature, division is frequently arrested and the new oral areas regress. Subsequent cell separation is greatly delayed and asynchronous.Heat and cold affect the micronucleus in the same way. Both agents prolong the arrest of mitosis brought about by the synchronizing treatment. A temperature shock is ineffective if applied after there is a space completely separating the chromosome groups, so that mitosis is completed in the presence of the agent. Bimicronucleate chains result in those cases in which division is arrested by heat shocks.It is suggested that the different phases of sensitivity to heat and cold may reflect different types of syntheses necessary for development of the oral primordium. Division arrest and subsequent oral replacement might possibly be related to high temperature induced changes in the physical state of the ciliate cortex.
Ultrastructure of Trypanosoma lewisi: Flagellum, Microtubules, and the Kinetoplast
Authors: ANDERSON W. A. , ELLIS R. A. 
Published: May 2007

SYNOPSIS. With the technique of preselecting pure suspensions of trypanosomes for subsequent electron microscopy and with epoxy resin embedding after glutaraldehyde fixation, we have re‐examined the ultrastructure of Trypanosoma lewisi with particular reference to the flagellum and pellicle. The peripheral flagellar tubules exhibit clockwise asymmetry; however, sub‐tubule B of the peripheral tubules is divided into a doublet by a diagonally running anti‐clockwise arm that originates from the median diaphragm. Projections which seem to be continuous with the counter‐clockwise arms extend into a “basket shaped” intra‐flagellar structure. This structure, originating distal to the flagellar pocket and running anteriorly within the flagellar membrane, may play a role in maintaining the rigidity of the flagellum.The central flagellar tubules have a double helical substructure and dense cross‐striae (diameter 50 Å), and are regularly arranged at distances of approximately 250 Å. The central tubules arise from separate kinetosomal plates that lie at two different elevations. One central flagellar tubule originates from a flattened kinetosomal plate which makes contact with the peripheral tubules. The other central tubule passes through the flattened plate to fuse with an underlying “disc‐like” plate.The primary kinetosome exhibits the uniform triplet pattern of tubules at its most proximal region. A pair of tubules closely associated with one of the triplets represents two of the four subpellicular tubules which penetrate the cytoplasm in the region of the flagellar pocket. Sub‐pellicular tubules of dimensions similar to the flagellar tubules form a uniform cytoskeleton in all regions of the cell except in the area of the flagellar pocket.A desmosome‐like structure maintains continual cell membrane contact with the flagellum and the pellicle. This structure is designated the attachment zone. The fine structure of the kinetoplast is demonstrated. The dense intra‐mitochondrial elements (presumably containing DNA) are actually tubules, embedded in a moderately dense matrix. Morphological observations indicate that this organelle is probably primarily concerned with the ontogenesis of mitochondria, and several mitochondria extend from it into the cytoplasm of the cell.
Neustonic Marine Craspedomonadales (Choanofiagellates) from Washington and California
Authors: NORRIS RICHARD E. 
Published: May 2007

SYNOPSIS. Neustonic choanoflagellates can be found in marine tide pools in the San Juan Islands, Washington, and on the Monterey Peninsula, California. Several marine photo‐synthetic Chrysophyceae (in the Pedinellaceae), which also occur in these regions, have a basic structure so similar to choanoflagellates that this family is placed in the Craspedomonadales. In pointing out this relationship, the derivation of the Craspedomonadales from pigmented Chrysophyceae is strongly indicated.In addition to the naked choanoflagellates, which are placed in the Codonosigaceae, these organisms produce loricae of two different types: 1) loricae possibly of cellulose and without visible structure in the light microscope (Salpingoecaceae), 2) loricae composed of silica strands, sometimes forming a mesh with large open spaces (Acanthoecaceae). Members of the latter family seem to be confined to a marine environment and are a prominent part of this investigation. Examination of several species with the electron microscope has revealed interesting details of lorica morphology that are not visible with the light microscope.Several new combinations of taxa are proposed in addition to new taxa, including 4 new species of Salpingoeca, 3 new species of Diploeca and 4 new species of Pleurasiga. Three new genera are described, Ellisiella gen. nov., Acanthoecopsis gen. nov., and Sportelloeca gen. nov.
The Fine Structure of Colpoda maupasi with Special Emphasis on Food Vacuoles*
Authors: RUDZINSKA MARIA A. , JACKSON GEORGE J. , TUFFRAU MICHEL 
Published: May 2007

SYNOPSIS. An electron microscope study of Colpoda maupasi Enriques, isolated from the intestine of the blue‐tongued skink Tiliqua nigrolutea, showed that the fine structure of this ciliate is similar in all respects to that of free‐living ciliates. The correspondence applies particularly to the structure, distribution and number of mitochondria. This organelle has a rich intramitochondrial structure in the form of microvilli; it is found close to the periphery, near the nuclear apparatus and in other parts of the cytoplasm. It was concluded that the association between Colpoda maupasi and Tiliqua nigrolutea was probably accidental and limited to the cyst stage. Thus electron microscopy confirmed a conclusion arrived at by light microscopy.The presence of numerous food vacuoles made it possible to study stages of digestion within this organelle. Four major types of food vacuole were distinguished. Type 1 food vacuoles are characterized by their large size, the presence of intact bacteria and abundance of water. In type 2 the food vacuole is deprived of water, the bacteria are pressed together and the nuclei have lost their structure. Type 3 food vacuoles contain only bacterial ghosts, cytoplasmic and nuclear material having been digested. Food vacuoles of this type are found only occasionally, suggesting their short duration. It is of interest that during this transient stage the bulk of digestion takes place. In type 4 nothing reminiscent of bacteria is found; there are only myelin figures and vesicles of different sizes. Evaginations and invagnations of the vacuolar membrane and vesicles of different size and structure inside and outside the food vacuoles of types 1, 3 and 4 suggest that extensive communication exists between the cytoplasm and the food vacuole. It seems likely that enzymes are delivered to the food vacuole and digested materials are released from the food vacuole to the cytoplasm.