bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE PRODUCTION OF HYDROGEN PEROXIDE BY BLUE‐GREEN ALGAE: A SURVEY1
Authors: Stevens S. E. , Patterson C. O. Pat , Myers Jack 
Published: August 2007

SUMMARYA survey of 38 axenic isolates of blue‐green algae indicated that over half the isolates produced hydrogen peroxide under defined growth conditions. Three kinetic profiles for the formation of hydrogen peroxide, were observed; these are described. The possible site or sites of hydrogen peroxide formation remain unknown.
CALCIFICATION AND ITS INHIBITION IN COCCOLITHOPHORIDS1,2
Authors: Dorigan Janet L. , Wilbur Karl M. 
Published: August 2007

SUMMARYThe protein synthesis inhibitors cycloheximide and chloramphenicol and the transport inhibitors LaCl3, oligoniycin, and ethacrynic acid were found to inhibit reversibly calcium uptake, coccolith formation, and cell division in the coccolithophorid Cricosphacra (Hymenomonas) carterae. With some, compounds, recovery of calcification was retarded, and in the case of oligomycin, incomplete. Glycerol, 0.5 M, partially reversed the inhibitory effect of chloramphenicol on calcification but not on division. Ouabain was without significant effect on calcium uptake but slowed division in 3 of 5 experiments. Ruthenium red inhibited, neither calcification nor division. In the absence of light, calcification did not occur.
THE POSSIBLE OCCURRENCE OF PHOTOSYNTHETIC MICROORGANISMS IN DEEP‐SEA SEDIMENTS OF THE NORTH ATLANTIC1,2,3
Authors: Malone T. C. , Garside C. , Anderson R. , Roels O. A. 
Published: August 2007

SUMMARYAn assemblage of 12 diatom species and other photosynthetic microorganisms associated with red clay sediments collected from a depth of 6150 m in the North Atlantic was observed to bloom in Antarctic bottom water when exposed to sunlight at sea surface temperature. Although no growth could be detected over the first 3 days of the experiment, nitrate was nearly completely stripped from the water. The maximum growth rate of 4.7 doubling/day was reached between days 4 and 5. Most of the diatom species have been described as littoral or coastal forms, and it is suggested that these organisms are transported to depth by fecal material, turbidity currents, or a combination of the two.
EFFECT OF LIGHT INTENSITY AND GLYCEROL ON THE GROWTH, PIGMENT COMPOSITION, AND ULTRASTRUCTURE OF CHROOMONAS SP.1,2,3
Authors: Faust Maria A. , Gantt Elisabeth 
Published: August 2007

SUMMARYGrowth of Chroomonas sp. increased with light intensity (100, 1800, and 2700 μW/cm2) with a fivefold increase from the lowest to the highest intensity. Chlorophyll and phycocyanin content per cell were greater in cells grown at low light intensity, but the ratio of chlorophyll a and c did not vary appreciably. Cells grown at low light intensity had 30% more phycocyanin than cells grown at high intensities of light. The chloroplast of cells with the higher phycocyanin content had average intrathyla‐koidal widths of 300 Å, whereas those cells with the lower phycocyanin content had average intrathylakoidal widths of 200 Å. This result is compatible with the hypothesis that phycocyanin is located in the intrathylakoidal space in the cryptophyte algae. Of the various energy sources tested, only glycerol was able to support limited growth tinder nonphotosynthetic conditions. Under no condition was the chloroplast reduced to an elioplast or proplastid state. Starch accumulation was greatest in cells grown in continuous while light in glycerol. Eye‐spots were commonest in cells grown in darkness and interrupted every 24 hr by a few seconds of white light. It was concluded that this organism is an obligate phototroph.
BACTERIA‐ASSIMILABLE ORGANIC COMPOUNDS, PHOSPHATE, AND ENHANCED GROWTH OF BACTERIA‐ASSOCIATED BLUE‐GREEN ALGAE1
Authors: Lunge Willy 
Published: August 2007

SUMMARYThe complexities of algal physiology and nutrition make it likely that diverse and often substantial nutrient limitations will be required to control eutrophication in different situations. In defense of a policy exemplified by the generalization “phosphorus is the primary limiting nutrient in most lakes,” Schindler of the Canadian Freshwater Institute has misquotated the work of Lange. Key points of Lange's conclusions are properly quoted, and the reader is cautioned against an oversimplification of a single approach to algal control.
CHARACTERIZATION OF BLEACHING IN CHLORELLA INDUCED BY SUBOPTIMAL GROWTH TEMPERATURES1
Authors: Marvin James W. , Karlander Edward P. 
Published: August 2007

SUMMARYIncubation of cultures of a high‐temperature strain of chlorella at 10 C stopped growth and bleached all chlorophyll in the cells in 24 hr. Optimal conditions of light (3.0 mw/cm2), gas (1% CO2‐in‐air), and inorganic medium for maximal growth at 39 C were maintained in the transfer from 39 to 12, 10, or 5 C. The bleaching process at 10 C is characterized by a lag period for the first few hours followed by a linear decrease in chlorophyll content of cultures. The amounts of time required to bleach half of the chlorophyll initially present (effective half‐times) at 10 C were 14 hr for chlorophyll a and 17 hr for chlorophyll b. Effective half‐times of bleaching for total chlorophyll were 47 hr at 12 C and 6 hr at 5 C. Addition of glucose to inorganic medium delayed but did not prevent bleaching. Use of argon gas instead, of 1% CO2‐in‐air prevented cells from bleaching in both inorganic and glucose media, and indicated an oxygen requirement for bleaching. Incubation of 6 additional strains of Chlorella at 10 C resulted in responses ranging from bleaching to no growth to growth.
SCENEDESMUS MORPHOGENESIS. COLONY CONTROL IN DILUTE MEDIA1
Authors: Trainor F. R. , Shubert L. E. 
Published: August 2007

SUMMARYMorphological stability, with the elimination of the unicellular singe, was achieved by culturing several strains of Scenedesmus in media with, low inorganic salt levels. Organisms stabilize and form only colonies at specific nutrient levels. One became colonial only when the salt level was dropped to 3.07 mg inorganic salts per liter, with N and P at levels found in nature.
THE EXTRACELLULAR RELEASE Of GLYCOLIC ACID BY A MARINE DIATOM1
Authors: Smith Walker O. 
Published: August 2007

SUMMARYThe excretion of glycolic acid by the marine diatom Chaetoceros socialis through time was studied. Excretion in axenic cultures was linear for the time intervals used, but for nonaxenic cultures an equilibrium was created, suggesting bacterial uptake of glycolic acid. In studies with an inhibitor of glycolate dehydrogenase, the level of glycolic acid in the medium jumped 15–fold. This shows the presence of this enzyme, and implies the presence of the entire set of enzymes which convert glycolic acid to serine and release carbon dioxide. In both axenic and nonaxenic cultures a steady state was reached. All of the data suggest that at high cell densities glycolic acid is liberated from the cell by a passive mechanism. The effect of such an excretion in natural waters is discussed.
MORPHOLOGY AND NUTRITION OF PANDORINA UNICOCCA SP. NOV.1,2
Authors: Rayburn William R. , Starr Richard C. 
Published: August 2007

SUMMARYEleven strains of Pandorina unicocca sp. nov. were studied for morphological characterization. The species was delimited by having cells which contain a single basal pyrenoid and by colonies which have cells separate from each other in the colonial envelope. A defined medium was developed for 4 strains of P. unicocca and the nutritional requirements of these strains were examined. All 4 strains were capable of completely autotrophic growth and they could utilize nitrate, ammonium, or urea as nitrogen sources. Optimum growth was nuts attained at pH 8.0.
COMPARATIVE PHYSIOLOGY AND MORPHOLOGY OF SIX STRAINS OF STIGONEMATACEAN BLUE‐GREEN ALGAE1
Authors: Martin Thelma C. , Wyatt J. T. 
Published: August 2007

SUMMARYSix strains of branched blue‐green algae were examined in a search for lines to an explanation for apparent noncompetitiveness. Classical taxonomic treatments were often inadequate for confident species determination; forms that were very differ their morphologically frequently “keyed” to the same species. Strain distinctions based on comparative morphological and physiological studies were inconclusive. With the exception of 1 species, there were no substantial differences in physiological rates. In addition to the branching habit, diversity of cellular form was found to be an outstanding group characteristic. Individual cells of developing trichomes became a spore‐like and then divided to produce either cell clusters or lateral branches. The eventual separation of daughter cells by sheath materials may be analogous to spore formation in Nostocales and could be the factor which determines the nature of these organisms. The Stigonemataceae may not represent the pinnacle of blue‐green algal development but may, instead, be a primitive and basic form linking coccoid and filamentous algae.
CALCIUM DEFICIENCY CAN INDUCE THE TRANSITION FROM OVAL TO FUSIFORM CELLS IN CULTURES OF PHAEODACTYLUM TRICORNUTUM BOHLIN1,2
Authors: Cooksey Keith E. , Cooksey Barbara 
Published: August 2007

SUMMARYThe diatom Phaeodactylum tricornutum Bohlin is known to be pleomorphic. Previously it was considered that growth on medium solidified with agar produced ovate cells, whereas growth in liquid medium gave rise to fusiform cells. We have shown that ovate cells can be propagated in liquid medium if the calcium content of the medium is below 15 mg/liter. If the concentration of calcium is raised, fusiform cells develop.
STRUCTURE OF THE PERIPLAST OFCRYPTOMONAS OVATAVAR.PALUSTRIS1,2
Authors: Faust Maria A. 
Published: August 2007

SUMMARYThe periplast ofCryptomonas ovatavar.palustrisis composed of polygonal plates which are delineated by shallow ridges. A small ejectosome is located at each corner of the plate area. The plate areas vary in size; they are smallest at the anterior and posterior ends and are largest in the middle of the cell with an average length of 0.5 μ and of width 0.4 μ. In cross section a plate area is composed of 2 distinct layers, an outer plasma membrane layer with a fine particulate, appearance, and an inner layer consisting of two sheets. The sheets of the inner layer have a striated lattice pattern with a periodicity of about 20 nm. In negatively stained preparations one lattice appears to underlie another at certain angles. Protease digestion removed polygonal shaped inner layer.
THE ULTRASTRUCTURE OF CARPOSPOROGENESIS IN THE MARINE HEMIPARASITIC RED ALGAERYTHROCYSTIS SACCATA1
Authors: Kugrens Paul , West John A. 
Published: August 2007

SUMMARYThe ultrastructure of carposporogenesis forErythrocystis saccatais described. The fusion and gonimoblast cells contain few organelles, and chloroplasts are in a proplastid state, with pit plugs between gonimoblast cells dissolving early in development. Carpospore development may be separated into 3 stages, the first stage being characterized by the appearance of straight‐profiled dictyosomes, fibrous vesicles, and an increase of discoid thylakoids within the chloroplasts. During the second, stage the dictyosomes assume a curved profile and striped vesicles are formed by the endoplasmic reticulum. The third stage is initiated by the disappearance of striped vesicles and the appearance of straight‐profiled dictyosomes secreting vesicles with cores. Mature carpospores consist of many cored vesicles, fibrous vesicles, and floridean starch grains. A single wall layer surrounds each carpospore since the carposporangial wall becomes incorporated into a mucilaginous matrix surrounding the spores.
SPORANGIAL STRUCTURE AND ZOOSPOROGENESIS IN CHORDA TOMENTOSA (LAMINARIALES)1,2,3
Authors: Toth Ronald 
Published: August 2007

SUMMARYMembers of the genus Chorda represent the simplest form of sporophyte in the order Laminariales. The present study deals with reproduction in Chorda tomentosa, involving the initiation, growth, and structure of the sporangium and the process of zoosporogenesis. The simple tube‐like sporophyte of Chorda tomentosa grows in diameter by means of repeated anticlinal divisions in a superficial meristematic layer known as the meristoderm. The onset of reproduction is marked by the conversion of the meristoderm from contributing cells to the vegetative plant body to producing 2 new cell types: paraphyses and sporangial mother cells. At the time of initiation, sporangial mother cells are crescent shaped and possess a densely staining cytoplasm. Sporangial mother cells increase in size, become ellipsoid, decrease in staining density, and undergo meiosis. After meiosis, sporangia increase in size while their nuclei undergo successive cycles of synchronous mitotic divisions. Sporangia increase to a maximum length of 120 μ;m at which time they possess the characteristic “cap” found in all members of the order studied thus far. At this stage the protoplast of the sporangium is organized into a peripheral layer of nucleus‐chloroplast pairs and a central region of vacuoles. Cleavage furrows begin to form at the cell membrane and are met by furrows developing in the interior of the cytoplasm resulting in the division of the entire protoplast into separate units. Each unit is an individual zoospore. The biflagellate zoospores contain a nucleus, one chloroplast with eyespot, perinuclear Golgi, and several bodies of presumed storage carbohydrate. The occurrence of a small population of early developing sporangia is described. In essential details, the origin, development, and structure of sporangia in Chorda tomentosa are identical to all earlier observations in the Laminariales.
PHYCOLOGICAL NOTES. III. TWO NEW SACCATE UNICELLULAR CHLOROPHYCEAE1
Authors: Bold Harold C. , MacEntee Frank J. 
Published: August 2007

SUMMARYComparative study, under standard conditions of growth in a variety of media, of 2 unicellular chlorophycean algae living in soil, both of which produce spherical and saccate cells in their development, has resulted in the description of 2 new taxa, Ascochloris multinucleata gen. et sp. nov., Chlorococcaceae, Chlorococcales, and Ignatius tetrasporus gen. et sp. nov. of the Chlorosarcinaceae, Chlorosarcinales.
CHLOROPLAST STRUCTURE AND PIGMENT COMPOSITION IN THE RED ALGA GRIFFITHSIA PACIFICA: REGULATION BY LIGHT INTENSITY1
Authors: Waaland J. Robert , Waaland Susan D. , Bates George 
Published: August 2007

SUMMARYThe ratio of accessory phycobiliproteins to chlorophyll a is controlled by light intensity in the marine red alga Griffithsia pacifica. The greatest changes in pigment ratios are observed below 300 ft‐c; above 300 ft‐c the response approaches saturation. Ultrastructural examination of chloroplasts of plants grown at different intensities reveals that the number of phycobilisomes per unit of photosynthetic thylakoid changes in direct proportion to the pigment ratios and in inverse proportion to the light intensity.
EXTRACELLULAR INVESTMENTS IN BLUE‐GREEN ALGAE WITH PARTICULAR EMPHASIS ON THE GENUS NOSTOC1
Authors: Martin Thelma C. , Wyatt J. T. 
Published: August 2007

SUMMARYThe investments of a wide variety of blue‐green algae were examined. Many strains formed diffuse slime layers that were unnoticed unless mounted in India ink. Slime occurred in species with and without readily detectable sheaths. The extracellular integument type seemed consistent within strains, although the extent often varied with culture conditions. Experiments with NOSTOC on agar plates indicated that motility was inversely related to the amount of slime present. Some aspects of behavior were related to the nature of an alga's investment.
A SEASONAL DIATOM IN A FROZEN WISCONSIN LAKE1
Authors: Boylen Charles W. , Brock Thomas D. 
Published: August 2007

SUMMARYAn extensive bloom of a stalked diatom, Cymbella sp., developed under the ice in Lake Wingra, a hard‐water lake in southern Wisconsin. The diatoms were attached to decomposing plants of Myriophyllum spicatum L. Uptake of H14CO3− showed the Cymbella to have an optimum temperature for carbon fixation of 25 C throughout the winter. Microscopic examination of samples taken from January through April showed Cymbella to dominate all other eucaryotic organisms. It is concluded that despite the fact this organism predominates in this winter habitat, it does not become optimally adapted to the temperature of its environment.
POLYMORPHISM IN THE DESMID MICRASTERIAS PINNATIFIDA AND ITS TAXONOMICAL IMPLICATIONS1
Authors: Sormus Laine , de Mattos Bicudo Carlos Eduardo 
Published: August 2007

SUMMARYA case of polymorphism in the desmid Micrasterias pinnatifida (Kütz.) Ralfs is described. It is based on material collected from the overflow channel of a dam in Caeté, Minas Gerais State.After careful examination of nearly 500 specimens, 26 different morphological expressions of the alga were found which led the authors to make the following deductions: (1) for delimitation of species and infraspecific taxa in desmids it is absolutely necessary to analyze sample populations; (2) the morphological characteristics presently used, for delimination of some varieties of M. Pinnatifida (Kütz.) Ralfs seem to have no taxonomical value if only isolated individuals are examined; (3) the varieties granulata, inflata, and tridentata must be considered with some caution, until further studies are carried out, because they can be merely distinct morphological expressions of M. pinnatifida (Kütz.) Ralfs var. pinnatifida.
GROWTH OF TWO FACULTATIVELY HETEROTROPHIC MARINE CENTRIC DIATOMS1,2
Authors: White Alan W. 
Published: August 2007

SUMMARYThe facultative, heterotrophs Cyclotella cryptica (sclone WT‐1‐8) and Coscinodiscus sp. were selectively isolated from coastal waters by dark incubation of organically enriched solid medium. C. cryptica grows in the dark with glucose and galactose, and Coscinodiscus sp. with glucose. Clone WT‐1‐8 of C. cryptica grows about twice as fast with glucose as a previously studied clone (0‐3A). In the dark with, 5 × 10−6 M glucose C. cryptica divides every 3 days, while with 5 × 10−5 M glucose Coscinodiscus sp. divides every 10 days. Heterotrophic growth of either diatom for 1 year does not cause a major reduction in carbon, nitrogen, chlorophyll a, and chlorophyll c contents, or in photosynthetic ability, compared to light‐grown cells. It is possible that facultative heterotrophy is of ecological benefit to these diatoms, probably for slow growth and survival during extended periods of dim light or darkness.
MICROMORPHOLOGY OF A SMALL DINOFLAGELLATE PROROCENTRUM MARIAE‐LEBOURIAE (PARKE & BALLATINE) COMB. NOV.1,2,3
Authors: Faust Maria A. 
Published: August 2007

SUMMARYThe surface structures of the bivalvate dinoflagellate Prorocentrum mariae‐lebouriae are described in detail. It has an almost spheroidal shape in face‐view, a compressed saucer‐shape in side view, with a distinct striated band at the edge of the cell. Its surface is covered with small spines in a regular pattern, with 450 nm distance between pairs. The spines are 100–120 nm wide and 200–300 nm long. There are 600–700 spines on each valve. At the anterior cell end, one of the values has a V‐shaped depression which contains a specialized structure accommodating the 2 flagellar pores. The flagellar pores are‐enclosed by 8 small, thick plates held together and to the values by sutures. The flagellar pore area consists of 2 distinct structures: an apical collar possessing a curved forked plate and a larger structure composed of an unbranched, plate. There are 2 flagellar canals located between the flagellar pore plates. Beneath each flagellar canal lies a row of 11 microtubules. A row of microtubules forming a microtubular cylinder is situated adjacent to the oblong flagellar canal near a simple pusule. The microtubular cylinder encircles electron dense bodies. The bases of the longitudinal and transverse flagella appear to lie at an angle to each other. The above features are illustrated with transmission and scanning electron micrographs.
PHYTOPLANKTON DISTRIBUTION AND WATER QUALITY INDICES FOR LAKE MEAD (COLORADO RIVER)1
Authors: Staker Robert D. , Hoshaw Robert W. , Everett Lorne G. 
Published: August 2007

SUMMARYPhytoplankton samples were collected in Lake Mead 6 times from September 1970 to June 1971 for 8 stations at depths of 0, 3, 5, 10, 20, and 30 m. These samples were processed through a Millipore filter apparatus and 79 planktonic algae were identified. Algal divisions represented were Bacillariophyta, 42 species; Chlorophyta, 18; Cyanophyta, 9; Chrysophyta, 3; Cryptophyta, 3; Pyrrophyta, 2; and Euglenophyta, 2. Blue‐green algae were dominant in late summer and fall; green algae, diatoms, and cryptomonads in winter; and green algae in spring. The early summer flora was best represented by the Chlorophyta, Cryptophyta, and Chrysophyta. Palmer's pollution‐tolerant algae indices and Nygaard's indices were calculated from, phytoplankton data. These indices suggest eutrophic conditions in Lake Mead, especially for Boulder Basin.
CHLAINOMONAS KOLII(HARDY ET CURL) COMB. NOV. (CHLOROPHYTA, VOLVOCALES), A REVISION OF THE SNOW ALGA, TRACHELOMONAS KOLII HARDY ET CURL (EUGLENOPHYTA, EUGLENALES)1,2
Authors: Hoham Ronald W. 
Published: August 2007

SUMMARYThe snow alga Trachelomonas kolii is transferred from the Euglenophyta (Euglenales) to the Chlorophyta (Volvocales) as Chlainomonas kolii comb. nov. As a result of critical examination of both living and type material, this species was found to have 4 flagella per vegetative cell, true starch, and 1 axial plastid per cell with several peripheral lobes. Vegetative cells of Trachelomonas kolii were described originally as having 1 flagellum, lacking true starch but having paramylum, and as having several parietal plastids per cell. The reticulate markings on the outer envelope of vegetative cells were found to be different from those in the original illustrations.Vegetative cells and resting spores of Chlainomonas kolii and Chlainomonas rubra are compared. The similarities of resting spores of Chlainomonas kolii and Chlamydomonas nivalis are discussed. These are the first records of Chlainomonas kolii from snow in Washington State.
ENDOCYTOSIS OF MICROCYSTIS AERUGINOSA BY OCHROMONAS DANICA1
Authors: Cole Garry T. , Wynne Michael J. 
Published: August 2007

SUMMARYOchromonas danicaPrings., a chrysomonad alga which demonstrates a high degree of nutritional versatility, is capable of feeding on the toxic blue‐green algaMicrocystis aeruginosaKuetz. In this paper light microscopic, electron microscopic, and cytochemical examinations of endocytosis inO. danicaare reported, with particular emphasis on the vicissitudes of endocytic and lysosomal activities during intra‐cellular digestion. An interpretation of the function of organelles associated with endocytosis is presented.
COMPETITIVE EXCLUSION AMONG THREE PLANKTONIC BLUE‐GREEN ALGAL SPECIES1,2
Authors: Lange Willy 
Published: August 2007

SUMMARYAlthough domination of 1 species in an algal community has often been attributed to toxic effects, nutrient exhaustion can also lead to competitive exclusion among algal species.The bacteria‐associated blue‐green algae Microcystis aeruginosa, Nostoc muscorum, and Phormidium foveolarum were cultivated in Zehnder‐Gorham's medium No. 11 individually and in their combinations. The growth rates of Microcystis and of Nostoc were reduced by the presence of Phormidium. This detrimental effect was apparently not due to formation of any toxic or allelopathic matter. It was caused by the reduction of iron and trace metal concentrations in the medium by Phormidium to levels too low for normal growth of Microcystis and Nostoc. Work with the axenic forms of the 3 algal species also indicated a lowering of iron and trace element concentrations by Phormidium to levels not sufficient for sustained growth of Microcystis and Nostoc. Thus, bacteria played no significant role in this example of competitive exclusion.