bluuebunny/crossref_metadata_2025 huggingface dataset:
68  A new paradigm for the aphanizomenon bloom problem in upper klamath lake
Authors: Henry E. C. , Geiger N. S.
Published: January 2004

Upper Klamath Lake (UKL) is the largest lake in Oregon (area 287 km2, avg. depth 4.2 m). It is naturally eutrophic and regularly suffers nuisance summer blooms of cyanobacteria, principally Aphanizomenon flos‐aquae (AFA). Sediment coring studies show that AFA was absent or minimal until about 1880 when a steady increase began, culminating in the blooms of recent decades. These studies show concomitant increases in sediment N (∼20%) and P (∼50%) along with shifts in the algal flora indicating increased eutrophication. These changes correlate with increased human impacts, such as deforestation, construction, roadbuilding etc., and especially the ditching, diking and draining of adjacent wetlands for conversion to agriculture. Agricultural nutrient runoff, especially P, has been often cited as the cause of the AFA blooms, and most attention has been focused on the dynamics of UKL during the summer bloom. We propose that a more significant factor may be the loss of early‐season suppression of AFA because of the loss of the lake‐associated wetlands, which originally constituted 42% of the lake area, and which have declined in area by 66.3% since the late 1800's. The melting of snow and ice in the spring would flush into the lake a surge of wetland plant decomposition products, most significantly organic acids and humic substances. We propose that formerly these wetland effluents caused a complex of effects on lake pH, solar UV transparency, photochemical interactions, nutrient availability, and Daphnia grazing dynamics, which would have combined to prevent the development of any AFA bloom.
7  Integrating autonomous data acquisition and forecasting into regional monitoring efforts; a synopsis of the merhab 2002: eastern gulf of mexico sentinel program
Authors: Bendis B. , Fries D. , Haywood A. , Kirkpatrick G. , Millie D. , Orsi T. , Scholin C. , Steidinger K. , Stumpf R. , Walsh J. , Weisberg B.
Published: January 2004

Blooms of the red‐tide dinoflagellate, Karenia brevis, occur annually in coastal waters of the eastern Gulf of Mexico (GOMx) and impact marine resources, public health, and community economics. Early forecasting of and subsequent mitigation for blooms are objectives of agency, academic, and private partnerships. The 5‐year, NOAA‐funded MERHAB 2002: Eastern GOMx Sentinel Program will develop and assess the utility of a networked system of autonomous sampling platforms. The goal of the program is to become a strategic, proactive hardware‐ and information‐technology for operational GOMx coastal observatories and as such, facilitate model initializations and state‐wide, adaptive field sampling. Monitoring platforms will utilize both existing and newly established buoys, and autonomous, water‐column profiling vehicles incorporating physical, chemical, and biological sensors. The biological sensors, including a bio‐optical phytoplankton discriminator and a processor containing a molecular‐probe array, previously have provided consistent results in laboratory and field trials and show great promise for remote, autonomous discrimination of K. brevis. Generated data will initialize a coupled bio‐physical forecast model and validate remote sensing algorithms for K. brevis blooms. Data acquisition and forecasting efforts will be integrated with a geographically‐comprehensive, rapid response component that incorporates adaptive, field sampling and a volunteer sampling network. NOAA's National Coastal Data Development Center will manage instrument data streams and disseminate and integrate all data into existing (and future) coastal partnerships with their associated management and communication network.
70  Use of molecular probe to detect taste/odor‐causing cyanobacteria in the phoenix drinking water distribution system
Authors: Hu Q. , Budinoff C. R. , Liu G. X. , Sommerfeld M. , Westerhoff P.
Published: January 2004

Tastes and odors caused by 2‐methyl‐isoborneol (MIB) and geosmin occur frequently in drinking water supply sources and aquaculture environments. Cyanobacteria often are implicated as culprit organisms responsible for production of these compounds. To develop cost‐effective and efficient mitigation measures to prevent or reduce the off‐flavors requires a sensitive, specific method with forecasting ability to detect the occurrence and distribution of the culprit species in a water system. Conventional biological (e.g., microscopy, isolation and cultivation of algae) and chemical (e.g., gas chromatography and mass spectrometry) methods are useful, but are usually incapable of providing predictive information. In this report, we introduce a new molecular fingerprinting technique for probing for the presence of cyanobacteria that have the genetic potential to produce MIB and geosmin. This method involves denaturing gradient gel electrophoresis (DGGE) analysis of PCR‐amplified 16S rDNA fragments. When analyzed by this method, the phylogenetic composition of benthic cyanobacterial assemblages differed substantially among ten permanent sampling sites along the Arizona Canal. The Arizona Canal is an open channel conveying water to four water treatment plants providing drinking water to over two million people in the Phoenix metropolitan area. Clear relationships were observed between specific DNA fingerprints, and episodes and intensity of MIB/geosmin production in specific sections of the canal. This suggests that the method could serve as a sensitive and reliable molecular method for early detection and forecasting of taste/odor episodes in water environments.
71  Proteomics of haematococcus pluvialis: new opportunities for study of genomics of a non‐sequenced species
Authors: Hu Q. , Sommerfeld M. , Wang S.‐B. , Chen S. F. , Liu G. X. , Hu Z. Y.
Published: January 2004

The green alga, Haematococcus pluvialis, has become a model organism for commercial production of the high‐value carotenoid astaxanthin. H. Pluvialis has also drawn significant scientific attention because fundamental biological questions relating to the massive cellular accumulation of astaxanthin have to be addressed in order to improve the yield and quality of the algal biomass. However, research has been impeded by the lack of molecular background information on this non‐sequenced species. A combination of classical biochemistry with a state‐of‐the‐art proteomic approach was used to address these questions. This was possible by taking advantage of information already available for homologous genes/gene‐products in organisms whose genomes have been sequenced. The approach involved isolation of subsets of the proteome from subcellular compartments/organelles of an organism by one‐ or two‐dimensional electrophoresis (1‐DE or 2‐DE) and their identification by N‐terminal sequencing and peptide mass fingerprinting (PMF), involving matrix‐assisted laser desorption/ionization and time‐of‐flight (MALDI‐TOF) mass spectrometry coupled with bioinformatics. Based upon the information obtained from the combined methods, expression and physiological functions of specific genes/encoded proteins may be deduced. Examples include profiling of cell wall proteins, biogenesis and protein composition of lipid bodies, and expression patterns of soluble proteins under stress conditions. Advantages and limitations of the method for non‐sequenced organisms and for cross‐species protein identification will also be discussed.
72  An examination of the periphytic algae in the sheyenne river, north dakota, usa, and the factors influence the community structure
Authors: Jaskowiak M. A. , Fawley K. P. , Fawley M. W.
Published: January 2004

The Sheyenne River is a third order stream in central and eastern North Dakota. The algae in this river had not been previously studied. For this study, periphytic algal samples were collected Fall 1997, April–November 1998, and May–October 1999. Two hundred sixteen periphytic algal taxa were identified. These taxa included 137 Bacillariophyceae, 33 Cyanophyta, 40 Chlorophyta, 8 Xanthophyceae, and 3 Euglenophyta. Several species of algae found in the river appear to be previously undescribed taxa. Two of these organisms were described as new species, Nitzschia sheyennensis and Nitzschia dakotensis (Bacillariophyceae). The distribution of the periphytic algae was correlated to changes in the selected environmental variables using canonical correspondence analysis (CCA) and mult‐dimensional scaling (MDS). The statistically significant environmental variables were nitrite‐nitrate, pH, arsenic, potassium, magnesium, manganese, and total dissolved solids. A reservoir, Lake Ashtabula on the river was formed by a dam in 1954. In the initial statistical analysis, the effects of this reservoir on the periphytic algae downstream were so great that an upstream/downstream covariable had to be used. Further statistical analysis was used to determined that this effect could be correlated to changes in the nutrient levels rather than hydrologic changes.
73  The use of algae to treat wastewater in the berkeley pit
Authors: Jemmings W. J. , Mitman G. G.
Published: January 2004

The Berkeley Pit in Butte, Montana is currently filled with 35 billion gallons of water, with 6 million gallons being added daily. The water in the pit contains a number of dissolved metals and other elements. These elements include: aluminum, iron, manganese, zinc, copper, cadmium, magnesium, nickel, calcium, sulfur, and silicon. Also, over 40 different types of small organisms live in the contaminated water. The purpose of this experiment is to examine the uptake potential of elements from Berkeley pit water by highly concentrated algal samples. The algae used are called Chlamydomonas acidophila. Chlamydomonas acidophila's optimum pH is between 3.5 and 4.5 and it may be capable of metal uptake by two mechanisms: absorption and adsorption. Adsorption and absorption are good alternatives to traditional wastewater treatments because algal cells are a naturally abundant renewable resource that can be cheaply produced. Algal cells are also highly selective in terms of removal and recovery of specific heavy metals, they do not require reagents, which typically cause disposal and space problems, and they require a relatively low initial capital investment with low operating costs. The experimental procedure involved using modified acid medium to grow algae from a stock solution to a concentration of 1.6×108 algae cells/mL. The growth medium was then washed from the algae cells. Three initial samples of sterile filtered pit water (SFPW) were set aside as a control. Then, concentrated algae cells were added to three centrifuge tubes. Next, SFPW was added to 3 tubes with algae and three tubes without algae. After 1 hour, a 5 mL sample was taken from each of the centrifuge tubes. After 24 hours, another 5 mL sample was taken from each of the centrifuge tubes. Inductively Coupled Plasma (ICP) analysis was performed on all the samples. The results from the initial SFPW were compared with those samples containing algae for 1 hour and 24 hours. Total metal uptake in 24 hours was roughly 7.81%.
74  Diversity of scenedesmus from itasca state park, minnesota
Authors: Johnson J. L. , Fawley M. W. , Fawley K. P.
Published: January 2004

The diversity of Scenedesmus and Scenedesmus‐like taxa from Itasca State Park, Minnesota was assessed using light microscopy and molecular techniques. Thirty isolates from various ponds and lakes in Itasca State Park were examined. Light microscopy showed many similarities in morphology among isolates, but PCR‐RFLP analysis of the ribosomal ITS region from these isolates revealed twenty different types. A previous study from Itasca State Park using only light microscopy found only six taxa of Scenedesmus; however, our results suggest that there is much greater diversity than previously suspected. DNA sequences of the 5.8S ribosomal subunit and the ITS‐2 region from our isolates are presently being determined and will be used to assess this diversity in greater detail.
75  The role of feeding in growth and photosynthesis of myrionecta rubra
Authors: Johnson M. D. , Stoecker D. K.
Published: January 2004

Myrionecta rubra (=Mesodinium rubrum) is an obligate phototroph that possesses plastids, mitochondria and sometimes nuclei of cryptophyte algae. Plastids and nuclei have been observed to increase in M. rubra when feeding. The current study was conducted in order to better understand the relationship between feeding and photosynthetic physiology in M. rubra. During the experiment, cryptophytes were introduced for 2 consecutive growth periods (14 d) and the cultures were then starved during 4 additional periods. Photosynthesis‐irradiance (PE) response curves were measured twice during each growth period (days 7 and 14), and the parameters alpha and Pmax were measured and normalized to cell and chlorophyll (chl) concentrations. In both treatments, growth rate and nuclei/cell increased significantly when fed (p<0.05), and then declined over time. Cell volume increased substantially in the HL treatment when in the presence of prey (p<0.05), but otherwise varied little. In both treatments, chl/cell and Pmax(cell) increased after feeding and then declined after several weeks in the absence of prey. Absolute changes in these parameters were greater in the LL treatment. In both treatments Pmax(chl) increased over the study. As observed previously, M. rubra appears to possess a limited capacity for producing pigments. While these results illustrate some dependency of photosynthesis and growth in M. rubra upon ingestion of cryptophyte prey, they also display that the ciliate can use and sustain plastids like a phototroph.
76  The Pneumocystis sam:smt, an atypical fungal enzyme protein
Authors: Kaneshiro E. S. , Basselin M. , Yarbrough D. N. , Smulian A. G.
Published: January 2004

Pneumocystis, an opportunistic fungal protist, causes a type of pneumonia in immunocompromised individuals such as AIDS patients. Rat‐derived P. carinii and human‐derived P. jiroveci contain a large number of sterols with C‐24 alkyl groups. S‐Adenosyl‐L‐methionine:sterol C‐24 methyl transferase (SAM:SMT) is the enzyme that transfers methyl groups from SAM to the C‐24 position of the sterol side chain. An alkyl group at the C‐24 sterol side chain position appears to be essential for the organism to proliferate. Thus SAM:SMT, which is absent in mammals, is an attractive target for chemotherapeutic attack against the pathogen. The P. carinii erg6 gene that codes for SAM:SMT has been sequenced, cloned, and the protein expressed in E. coli. Since bacteria do not synthesize sterols, and do not have SAM:SMT, the P. carinii erg6 gene product expressed in E. coli would only transmethylate exogenously provided sterol substrates. The P. carinii recombinant SAM:SMT is unique because lanosterol, a central intermediate in sterol biosynthesis, is its preferred substrate for enzyme activity. Most SAM:SMT from other organisms do not bind lanosterol and prefer other sterol substrates produced from lanosterol. Furthermore, it appears that this unusual P. carinii SAM:SMT can also methylate cholesterol, which is readily scavenged from the lungs of its rat host. The recombinant enzyme protein is being purified by affinity chromatography techniques, which will be used to obtain definitive structural analyses of the sterol compounds formed by the enzyme reaction using different sterols substrates and allow detailed structural analysis of this unusual SAM:SMT enzyme protein.
77  Cryptic speciation of Peridinium Limbatum
Authors: Kim E. , Graham J. , Graham L.
Published: January 2004

Cosmopolitanism vs. endemism of microbial diversity in water has been debated for a long time. Finlay (2002) argued that reported similarities in microbial biodiversity in different lakes and oceans support cosmopolitanism of microorganisms. Lee and Patterson (1998) suggested that many endemism studies are flawed due to underrepresentation of taxa. On the other hand, Theriot and Stoermer (1984) showed that Stephanodiscus niagrarae, the centric diatom once thought to be a cosmopolitan species, actually consists of four slightly different species. Mating tests of Paramecium aurelia revealed 14 sibling species, which are morphologically almost identical (Sonneborn, 1957). Here, I present evidence for the cryptic speciation of Peridinium limbatum from two water bodies (Crystal Lake and Crystal Bog) that are near each other but chemically distinct. We observed that the two Peridinium limbatum had different responses to the same growth medium. Previous works at the Microbial Observatory program showed that their seasonal population dynamics were also different; while a summer bloom of Crystal Bog Peridinium limbatum was correlated with a dramatic decrease in phytoplankton diversity, and an extreme drop in bacterial diversity, a bloom of Crystal Lake Peridinium limbatum was not. To see the genetic variations in this study, I sequenced internal transcribed spacer region 1 and 2 from the two Peridinium limbatum. The sequence variations were 8.53% in ITS1 and 8.06% in ITS2, which were much larger than within variations. In another ongoing study that I expect to complete before the meeting, I've been testing their possible allelopathic differences on Cryptomonas.
78  A comparison of four native Porphyra species from coastal new england in response to ammonium and temperature in small tank system
Authors: Kim J.K. , Kraemer G.P. , Neefus C.D. , Chung I.K. , Yarish C.
Published: January 2004

Porphyra is one of the world's most valued maricultured seaweeds. The effects of ammonium concentration and temperature on growth and tissue nitrogen content of Porphyra from coastal New England were studied in 50 liter tanks to produce critical information for the development of a land based aquaculture system. Four Northwest Atlantic Porphyra species: P. leucosticta, P. amplissima, P. linearis and P. umbilicalis, were cultivated for two to three weeks at saturating light intensities (100–150?Em‐2s‐1) and six combinations of ammonium (25 and 250?M) and temperature: 10, 15 and 20?C. The specific growth rate (SGR) of all species under most temperature conditions was significantly higher at 250?M than at 25?M ammonium. P. leucosticta showed higher growth rate at 10 and 15?C (10%d‐1 at 250?M versus 9 – 9.5%d‐1 at 25?M) in the first week. The SGRs of P. linearis in the second week and P. umbilicalis in the first week were the highest at 10?C (16 and 10%d‐1 at 250?M versus 12 and 8%d‐1 at 25?M, respectively). The SGR decreased with increasing temperature. In contrast, P. amplissima showed the highest SGR at 20?C (9%d‐1 at 250?M versus 7%d‐1 at 25?M) in the first week, and the SGR decreased at lower temperatures. Nitrogen concentration in tissue of P. leucosticta was significantly higher at 250?M than at 25?M. The rapid nutrient assimilation and fast growing ability makes Porphyra an excellent candidate for bioremediation and integrated aquaculture.
79  Systematic revision of Phaeostrophion Irregulare (phaeophyceae) and proposal of a new family phaeostrophionaceae
Authors: Kawai H. , Sasaki H. , Maeba S. , Henry E.C.
Published: January 2004

Phaeostrophion irregulare S. & G. is distributed along the Pacific coast of NW America, and has been placed in the family Punctariaceae, order Dictyosiphonales (or Ectocarpales s.l.), based on morphological resemblances. Culture studies have indicated a direct life history, with erect thalli forming unilocular and/or plurilocular sporangia. However, the occurrence of a perennial prostrate system (holdfast), presence on the holdfast of marginal meristematic cells, and lack of pyrenoids in the chloroplasts, suggest that this taxonomic assignment is questionable. Our TEM observations confirm the lack of pyrenoids in the chloroplasts. The occurrence of reductive divisions in the unilocular sporangia was confirmed by comparing the DNA content in each nucleus using a fluorescent stain, but both unilocular and plurilocular sporangia‐bearing erect thalli showed diploidy. Molecular phylogenetic analysis using rbcL (chloroplast) and 18S rDNA (nuclear) gene sequences reveals that Phaeostrophion is not included in the clade of Ecotocarpales s.l., but diverged relatively early in the evolution of Phaeophyceae, forming a clade with Sphacelariales and Syringodermatales, which share the apical/marginal meristematic mode of growth. Although we propose a new family Phaeostrophionaceae to accommodate Phaeostrophion, we suspend judgment of the appropriate taxonomic treatment at the ordinal level.
8  Grazing by heterotrophic nanoflagellates on virus‐ and bacteria‐sized particles in two lakes of different trophy
Authors: Bettarel Y. , Sime‐ngando T. , Amblard C.
Published: January 2004

Although viruses are now widely recognized to infect aquatic bacteria as well as prokaryotic and eukaryotic phytoplankton, our understanding of how they fit into aquatic foodwebs remains still deficient. The present study examined the potential nutritional food source that viral particles represent for natural assemblages of heterotrophic nanoflagellates (HNF). We determined the seasonal and depth‐related variability in the grazing activity of HNF on virus‐ and bacteria‐sized particles in the oligomesotrophic Lake Pavin and the eutrophic Lake Aydat. Ingestion rates were determined using 50 and 500 nm diameter fluorescent microspheres. Estimated ingestion rates ranged from 0.01 to 1.7 viruses cell−1·h−1 (Aydat) and from 0.01 to 2 viruses cell−1·h−1 (Pavin). Derived clearance rates for viruses represented 3–5% (Aydat) and 10–12% (Pavin) of those for bacteria. In general, HNF grazing on both viruses and bacteria showed a similar pattern characterized by an apparent decrease in summer followed by autumnal peaks, with lowest values always being recorded in the hypolimnion. Viral production, estimated from the frequency of visibly infected cells (using transmission electronic microscopy), was consumed by HNF at rates averaging 2% (Aydat) and 10% (Pavin). This study suggests that, viruses, which are assumed to correspond to 1×10−7 ng C/particle, are likely to be of low nutritive value for HNF in both lakes. However, these results imply that HNF grazing may contribute significantly to the removal of viruses in freshwaters, especially in low productive systems.
80  Purification and characterization of male and female gamete recognition molecules of a marine red alga aglaothamnion oosumiense
Authors: Kim G.H. , Jo B.H. , Chean H.J.
Published: January 2004

In red algae, fertilization begins with gamete‐gamete contact between the trichogyne cell wall of the female carpogonium and spermatial coverings. During the fertilization in Aglaothamnion oosumiense, reproductive cells interact with each other through sex specific adhesion molecules on the surface of spermatia and trichogyne. The gamete binding is highly selective suggesting the presence of recognition factors along their surfaces. In the previous studies, we have reported that spermatial binding to trichogynes of a red alga, Aglaothamnion oosumiense is mediated by a lectin‐carbohydrate complementary system. Spermatial binding to trichogynes was inhibited by pre‐incubation of trichogynes with N‐acetyl‐D‐galactosamine and D‐glucose and hence lectins specific to these sugars were expected to present on the surfaces of trichogyne cell wall. We have isolated a new lectin from Aglaothamnion oosumiense by the use of agarose bound N‐acetyl‐D‐galactosamine affinity chromatography and named it as rhodobindin. Rhodobindin agglutinated human erythrocytes as well as spermatia of Aglaothmanion oosumiense. The agglutinating activity of this lectin was inhibited by N‐acetyl‐D‐galactosamine and N‐acetyl‐D‐glucosamine. SDS‐PAGE results showed that this lectin may be monomeric. The molecular weight was determined as 21,876 dalton by matrix‐assisted laser desorption ionization (MALDI) mass‐spectrometry. N‐terminal amino acid sequence of the lectin was analyzed and revealed to have no identity with those of known proteins. The complementary male glycoprotein was also isolated and purified by the use of SBA‐agarose affinity chromatography. The subtractive cloning was carried out to characterize the recognition molecules.
81  Recent introduction of polysiphonia morrowii (ceramiales, rhodophyta) to punta arenas, chile
Authors: Kim M.S. , Yang E.C. , Mansiella A. , Boo S.M.
Published: January 2004

Polysiphonia morrowii (Rhodomelaceae, Rhodophyta) is abundant intertidally in spring in the Northwest Pacific. The species occurs in a large part of the North Sea and in Thau Lagoon, France, showing disjointed distributions, where the alga has been probably introduced recently. Using plastid protein‐coding rbcL sequence data from specimens of P. morrowii and putatively related taxa, collected in Korea, Japan and Far‐east Russia, and Chile, we tested the taxonomic position of each taxon. Pairwise divergence and topology of the sequences indicate that the Chilean taxon was identical to P. morrowii and was clearly separated from other related taxa from Chile. The results suggest that P. morrowii is recently anthropogenically introduced from the Northwest Pacific to Chile by boat or by transport with aquacultured organisms. Detailed observations of field‐collected material will probably enable a more realistic evaluation of distribution of P. morrowii to be made in the Pacific Ocean.
82  Taxonomic revision of sphaerotrichia divaricata (C. AG.) kylin (ectocarpales S.L., phaeophyceae), with a reappraisal of s. firma (GEPP) a. zinova from the northwestern pacific
Authors: Kim S.‐H. , Peters A. F. , Kawai H.
Published: January 2004

Specimens of Sphaerotrichia in Japan can be classified into two morphotypes based on mode of branching and anatomy: 1) specimens having an obvious (traceable) main axis associated with more first‐order branches, and the distance between the branches is relatively constant; 2) specimens that branches more or less divaricately and the distance between branches tends to be shorter in the distal portion. Molecular analyses of North Atlantic and North Pacific Sphaerotrichia using ribo‐somal RNA (ITS1‐5.8S‐ITS2 and IGS regions between 26S and 5S rDNA) and Rubisco (almost complete rbcL gene and the spacer between rbcL and rbcS) gene sequences revealed that there are two major genetic groups (i.e. Group‐1 and Group‐2), whereas the sequence length variation in ITS1 suggested subdivisions of Group‐2 into two subgroups (Group‐2Atlantic and Group‐2Pacific). Specimens belonging to Group‐1 were generally epilithic, and morphologically corresponded to Sphaerotrichia firma (Gepp) A. Zinova. Specimens belonging to Group‐2 were epiphytic or epilithic and morphologically corresponded to S. divaricata (C. Ag.) Kylin.
83  Comparative analysis of vertically migrating euglena viridis populations in tidal and non‐tidal benthic environments
Authors: Kingston M.B.
Published: January 2004

Benthic populations of Euglena viridis exhibit vertical migration behavior on high energy intertidal beaches and along the sand banks of freshwater streams. This study examines similarities and differences in the migratory behavior and cell morphology of populations of E. viridis inhabiting Scripps Beach, La Jolla, California and Coble Brook, Burlington, North Carolina. The timing of migration was measured by counting the number of cells in samples collected from the sediment surface throughout the day. Sediment cores were extracted and sectioned to determine the vertical distribution of the population. Neutral density filters and opaque canisters were used to shade the substratum to 56%, 22%, 2%, and 0% of incident irradiance (Io) to examine the effect of light on cell morphology and migratory behavior. On intertidal beaches, E. viridis exhibited a tidal rhythm in vertical migration with cells migrating below the sediment surface at night (>15 cm) and during daytime high tides. In this habitat, the upward migration response was enhanced at irradiances lower than 100% Io but cell morphology was not altered by shading. On the banks of freshwater streams, E. viridis exhibited a diurnal migratory rhythm with both tear‐drop and spherical morphologies observed throughout the day. The population was most concentrated at the surface around solar noon and at night it was located between 1 and 2 cm below the surface. Shading did not enhance upward migration but it did affect cell morphology. These results will be interpreted in the context of the dominant selection pressures in each environment.
84  Linking environmental forcing, kelp forest habitat dynamics, and community structure in the northeast pacific
Authors: Kinlan B.P.
Published: January 2004

Habitat‐forming species of large brown macroalgae (e.g., kelps) often differ from associated benthic species in resource requirements, sources of disturbance, and dispersal ability. Differences in environmental drivers and demographic processes may cause these habitats to fluctuate at spatial and temporal scales that differ from the “optimal” scale that would promote maximum abundance of any particular associate species. As a result, the spatiotemporal dynamics of habitat may exert important effects on benthic community structure and composition. To quantify the spatial and temporal dynamics of giant kelp (Macrocystis pyrifera), a key habitat‐former in the NE Pacific, I analyzed a 34‐year monthly time series of estimated canopy biomass spanning ∼1500 km of coastline (7° of latitude) and digital maps of annual maximum canopy cover. Canopy biomass varied interannually at dominant periods of 4–5 y, 11–13 y and ∼20 y, and spatial scales ranging from local (∼30 km) to mesoscale (∼100–150 km) and regional (∼330 km). Temporal dynamics were strongly related to basin‐scale climate fluctuations (El Niño‐Southern Oscillation, Pacific Decadal Oscillation) and spatial patterns were correlated with coastline geomorphology. Digital canopy maps reveal that changes in biomass are associated with shifts in the spatial structure of the kelp habitat. Long‐term subtidal community monitoring data from areas with markedly different spatial and temporal scales of kelp forest habitat structure reveal a complex but important influence of habitat dynamics on the distribution of life histories within kelp‐associated communities. Future changes in the dynamics of Pacific climate fluctuations may have important implications for kelp forest community structure.
85  Regeneration of protoplasts from disintegrated cells of the multi‐cellular marine green alga microdictyon umbilicatum
Authors: Klotchkova T.A. , Kim J.M. , Kim G.H.
Published: January 2004

Protoplast regeneration from extruded cytoplasm of the multi‐cellular marine green alga Microdictyon umbilicatum (Velley) Zanardini (Cladophorales, Anadyomenaceae) was investigated. The early process of protoplast formation is comprised of two steps: agglutination of cell organelles into protoplasmic masses followed by generation of a temporary enclosing envelope around them. Agglutination of cell organelles was mediated by a lectin‐carbohydrate complementary system. Three sugars, D‐galactosamine, D‐glucosamine, and a‐D‐mannose, inhibited the agglutination process, and three complementary lectins for the above sugars, peanut agglutinin, Ricinus communis agglutinin and concanavalin A, bound to the surfaces of chloroplasts. Agglutination assay using human erythrocytes showed the presence of lectins specific for the above sugars in the algal vacuolar sap. The lectin has been purified by the use of D‐mannose agarose affinity column. Its Molecular weight was shown to be 36,000 dalton by SDS‐PAGE gel electrophoresis. When the basic regeneration process was accomplished, the cells chose one of two developmental strategies; about 70% of one‐celled protoplasts transformed into reproductive cells within two weeks after wounding, while others began cell division and grew into typical Microdictyon plants. Quadriflagellate swarmers were liberated from the reproductive cells, and they germinated into mature plants
86  Chloroplast genome phylogenetics: facts and opinions
Authors: Kowallik K.V.
Published: January 2004

Recent progress in sequencing genomes from primary and secondary plastids provided various data including genomic complexities, gene sequences, gene complements, gene cluster organizations and rearrangements as well as secondary gene losses/gene relocations. They are considered to reflect evolutionary traits at different phylogenetic levels. However, current views of the validity of individual data sets are controversial and sometimes appear to reflect opinions rather than facts. Here I will present the plastid genomes of the Xanthophyte Vaucheria bursata and the brown alga Dictyota dichotoma and compare these genomes with those of other algae containing secondary plastids of rhodophytic origin. Gene complement analysis will focus on differential gene losses across evolutionary lineages and gene cluster rearrangements as a consequence of numerous inversions unknown from land plants. It will be discussed whether rearranged gene clusters common to two lineages, to the exclusion of others, may reflect parsimonious events or simply resulted from random independent processes. Although specific characters are encountered among all plastid genomes sequenced to date, the plastid genomes of Vaucheria and Dictyota confirm the presence of a basal set of 46 protein coding genes common to all plastid genomes of algae and metaphytes that have been used to infer a monophyletic origin of primary plastids and their evolutionary offsprings.
87  Algal bioremediation of eutrophic effluents in small scale integrated aquaculture systems
Authors: Kraemer G.P. , Pereira R. , Snellgrove D. , Carmona R. , Neefus C. , Chopin T. , Yarish C.
Published: January 2004

Non‐point source eutrophication of coastal waters is a significant problem that may be exacerbated locally by effluent from aquaculture operations. Porphyra spp. grow and assimilate nutrients rapidly, making them good candidates for eutrophication abatement via systems of integrated aquaculture. I summarize our work examining the bioremediatory performance (growth rate, nutrient assimilation, tissue N and pigment content) of four U.S. and three Asian Porphyra species as functions of N concentration and source (nitrate vs. ammonium). The Northeast U.S. species P. amplissima is the best performing local bioremediator (maximum growth rate and tissue N=24% d‐1, 5.2% DW, respectively), comparing well with P. yezoensis, an economically important species in Asia. When tissue remained non‐reproductive, P. amplissima growing in 300 μM ammonium removed 99–100% of N but only about 50% of P (fed 10:1 molar N:P ratio). We have begun investigating the relationship between stocking density and yield, and will begin demonstration scale tests of the mesoscale system.
88  Preliminary observations on the identity of the red algal genus Caloglossa (delesseriaceae, ceramiales) in the northwestern gulf of mexico
Authors: Krayesky D.M. , Fredericq S.
Published: January 2004

Phylogenetic analyses inferred from rbcL sequences indicates that specimens of Caloglossa (Harvey) G. Martens collected from Vermilion Bay, Louisiana and Galveston, Texas, reported as C. leprieurii (Montagne) G. Martens (1869) constitutes a separate taxon. Studies are presently being conducted to compare this northwestern Gulf of Mexico taxon with material of C. intermedia Kamiya et West in Kamiya et al. (2000, J. Phycol. 36:411‐420) from the Western Atlantic coast and with C. apomeiotica West et Zuccarello in West et al. (1994, Bot. Mar. 37:381–390) from Baja California, Mexico.
89  Morphological and molecular characterisation of four nostoc species isolated from desert soils
Authors: Kubeckova K. , Johansen J.R. , Li X.
Published: January 2004

Four unusual strains of Nostoc species from desert soils of the western United States were chosen for morphological and molecular characterization. The morphological characteristics of the desert Nostoc were compared with the species of Nostoc described in the literature. Although our strains were similar to previously described species such as N. punctiforme, N. paludosum, N. commune, N. microscopicum and N. muscorum, they did not fit any of these taxa well when all characters (including ecological preference) were used. The 16S rRNA gene sequences of the strains CM1‐VF10, CM1‐VF14, CNP‐AK1 and JT2‐VF2 were aligned with published Nostoc sequences from GenBank and other desert Nostoc sequenced at John Carroll University. Pseudanabaena, Cylindrospermum sp. and Anabaena spiroides from GenBank were used as outgroups. In addition, the ITS regions of all four desert taxa, a typical Nostoc commune from European temperate soils, Nostoc punctiforme PCC73102 from cycad roots were compared by examining secondary structure. The combined analysis provided compelling evidence that CM1VF10, CM1VF14, and JT2VF2 were species new to science. While CNP‐AK1 (the phycobiont of the desert soil lichen, Collema tenax) had some significant discontinuities from its closest relative, N. punctiforme, we consider the evidence currently insufficient to separate these two strains. The purported phycobiont of this lichen is N. commune, and we have demonstrated that this is incorrect. One of the desert strains (JT2‐VF2) likely represents a new genus. Morphological autapomorphies, distinctive SSU rRNA gene sequence, and differences in secondary structure of the 16S‐23S ITS provide congruent evidence for this conclusion.
9  Beyond biogeography: large‐scale patterns of distribution and abundance of intertidal marine algae along the us west coast
Authors: Blanchette C. A. , Raimondi P. T. , Wilson M. , Lohse D. , Kendall A. , Kusic K. , Livingston H. , Maloney E. , Williams M.
Published: January 2004

Biogeographers have long been intrigued by the richness and diversity of the Northeast Pacific algal flora. Most studies have focused attention on distributional patterns delineated into provinces and most strongly influenced by temperature. However, biogeographical studies have always been plagued by the necessity of interpreting distributional data that may be incomplete, non‐quantitative, limited in spatial extent and taxonomic resolution. We attempt to overcome some of these impediments by providing a quantitative description of intertidal community structure across a large spatial scale; ranging from northern Washington to southern California, including the California Channel Islands. We quantified patterns of distribution and abundance of marine algae and invertebrates in permanently marked grids extending 30 m along the shoreline and vertically from the upper barnacle zone to the surfgrass zone at MLLW. We identified most organisms to species level, when possible and collected voucher specimens of all taxa. Here we present the results of these studies focusing on geographic patterns of algal richness and diversity, patterns of abundance across geographical ranges, and functional group abundances relative to regional and mesoscale oceanographic patterns.
90  Initial characterization of the terminal domains of linear plasmid‐like dna's from ernodesmis verticillata (chlorophyta)
Authors: La Claire J.W. , Wang J.
Published: January 2004

Terminal regions of linear plasmid‐like DNAs from the chloroplasts of Ernodesmis verticillata (Kützing) Bøergesen were characterized. The 2.2‐kb molecules are believed to consist of a single strand of DNA folded back on itself in a hairpin configuration. The 5′ end of isolated molecules is capable of being phosphorylated with polynucleotide kinase, and the 3′ end can be homopolymeric tailed with terminal deoxynucleotidyl transferase. Thus, both ends are accessible for further manipulation. Exonuclease III and lambda exonuclease digest native molecules only after heat denaturation and certain cooling regimes, suggesting that conformational changes brought about by de‐ and renaturation make the 3′and 5′ ends (respectively) vulnerable to exonuclease activity. The cloning strategy involved poly‐G tailing of native molecules, and hybridizing them to a poly‐C‐tailed vector. Two rounds of cloning the 3′ ends yielded a total of 14 clones. Molecular sequencing revealed that two distinct clones have extensive terminal inverted repeats (TIRs). Short TIRs are also evident in most clones, possibly indicating that molecular foldbacks protect the 3′ ends. Multiple tandem and direct repeats are also prevalent near the 3′ termini. Despite overall sequence heterogeneity among most clones, a consensus sequence found at the 5′ end of these clones probably has structural and/or functional significance. Pairwise sequence comparisons and the presence of extensive repeats suggest that these molecules may be highly recombinant.
91  Maintenance of genetic diversity in heterosigma akashiwo by temporal variability in its environment
Authors: Lakeman M.B. , Cattolico R.A.
Published: January 2004

Heterosigma akashiwo (Hada) Hada ex Y. Hara et Chihara (Chromophyta: Raphidophyceae) is a coastal HAB forming species that is not known to undergo sexual reproduction. Ribosomal ITS sequences for 36 strains of Heterosigma have been determined and found to be identical except for two strains that had one single nucleotide polymorphism each. Despite the apparent absence of meiosis and the ostensible homogeneity of genotypes (at least at the ITS locus), different strains of Heterosigma display a very wide range of phenotypes. This inconsistency suggests that greater genetic diversity exists in Heterosigma than is evident through sequence analysis of the ITS region. Data will be presented summarizing efforts to develop better genetic markers for examining intrapopulational diversity. Results of experiments examining the effects of nutrient concentration in batch culture on growth response have demonstrated that sufficient haplotype variability exists in established culture strains to allow Darwinian selection, even when these strains are “clonal”. We propose that batch culture imposes a sequence of different selection pressures on a rapidly dividing population of cells, and this environmental variation promotes the maintenance of genetic diversity. Extrapolating the batch culture scenario to the much more highly dynamic marine coastal environment, it becomes apparent that the observed phenotypic variation between Heterosigma strains is largely a function of a diverse haplotype distribution, maintained, in a large part, by patchy resource availability on both temporal and spatial scales.
92  Phylogenetic analysis of the caulerpales (ulvophyceae, chlorophyta) based on rbcl gene sequences
Authors: Lam D.W. , Zechman F.W.
Published: January 2004

Our research seeks to clarify the phylogeny of the Caulerpales through analyses of rbcL (large subunit of ribulose 1,5 biphosphate carboxylase/oxygenase) gene sequences. In a review of caulerpalean taxonomy, Hillis‐Colinvaux (1984) recognized two suborders (Bryopsidineae and Halimedineae) on the basis of anatomical, physiological, and habitat characteristics. The Bryopsidineae (including the genera Bryopsis, Derbesia, and Codium) have cosmopolitan distributions, non‐holocarpic reproduction, and homoplasty, while the Halimedineae (including Caulerpa, Halimeda, and Udotea) have tropical to subtropical distributions, holocarpic reproduction, and heteroplasty. Previous phylogenetic analyses based on 18S rRNA sequence data supported the hypothesis of two monophyletic suborders within the Caulerpales (Zechman et al 1990). However, cladistic analyses of morphological characters (Vroom 1998) suggested that only the Halimedineae was monophyletic. Preliminary maximum likelihood and Bayesian analyses suggest the Halimedineae and Bryopsidineae form separate monophyletic groups, with robust support (bootstrap and posterior probabilities) for the former and moderate to poor support for the latter. The families of the Halimedineae (Caulerpaceae, Udoteaceae) form monophyletic sister groups with robust support. The freshwater family Dichotomosiphonaceae was inferred to be basal to the marine Halimedineae clade. The families within the Bryopsidineae (Derbesiaceae, Bryopsidaceae, Codiaceae) each form distinct monophyletic groups. The Codiaceae forms a basal monophyletic group to the sister clade of Bryopsidaceae and Derbeseaceae. This research was partially supported from a NSF grant (DEB‐0128977 to FWZ).
93  Progress in characterizing the symbiodinium sp. in soritid foraminifera
Authors: Lee J.J. , Harrison M. , Byfield C. , Lee S. , Médor G.
Published: January 2004

Various methodological approaches are being used to characterize Symbiodinium spp isolated from Marginopora vertebralis and Amphisorus hemprichii from the Indo‐pacific. While most of the cells in culture are non‐motile vegetative cells, dinospores are occur in batch cultures. We find consistant variance among the isolates in the duration and time of appearance. Nitrate (0.146 mM) supports higher populations of the isolates than does NH4 (0.146 mM). Higher concentrations of NH4 inhibit growth. Although Fensome et al (1993) characterized the Order Suessiales (and Family Symbiodiniaceae) as gymnnodiniphycideans in which the amphiesmal vesicals are arranged in 7–10 longitudinal series we were unable to detect any plates on the surfaces of our isolates in the SEM. Following Klut et al (1988) we unsuccessfuly attempted to reveal plates by using freeze fracture. We were more successful in using various chemical agents (e.g. H2O2, HOCl‐) and enzymes (cellulase, chitinase) to remove surface layers. Amphiesmal plates are present but they are not polygonal or arranged in the patterns anticipated for the Symbiodiniaceae. Polyclonal antibody studies are in agreement with molecular systematic studies in the sense that there is a common relatedness; the foram endosymbiotic dinoflagellates share some common surface antigens with each other and with the one invertebrate isolate we have tested. Studies of the foraminiferal symbionts' plastids revealed considerable morphological diversity. These studies were supported by NIH/NIGMS 08168‐22 and PSC‐CUNY grant 64234‐00 33.
94  An obligate(?) heterokont biflagellate parasite in codium fragile
Authors: Lee T. F. , Kugrens P.
Published: January 2004

Specimens of Codium fragile (Suringar) Hariot ssp. tomentosoides were collected from 9 sites in New England, and Long Island, New York at intervals throughout the years 1999‐2003. Segments were removed from the thalli and chopped into fine fragments, mostly individual utricles and medullary filaments. Fragments were incubated in enriched seawater in dim light at 15C, 12:12 LD. Within 2–3 days, in almost all cases (more than 300) motile cells formed in many of the utricles and filaments. These were 10–15 micrometer elongated biflagellate heterokont cells. They appeared to consume the chloroplasts, and within 24 hours were reduced to colorless cells, about 5 micrometers long. These cells are unable to grow in Codium chloroplast suspensions. They appear to be always associated with Codium thalli, despite attempts to clean the thalli, and were never seen in utricles or filaments of intact plants. Their ultrastructure is under investigation and will be reported on here.