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Targeted Disruption Of The Α-Amylase Gene In The Hyperthermophilic Archaeon Sulfolobus Solfataricus, Penny Worthington, Viet Hoang, Francisco Perez-Pomares, Paul H. Blum Jan 2003

Targeted Disruption Of The Α-Amylase Gene In The Hyperthermophilic Archaeon Sulfolobus Solfataricus, Penny Worthington, Viet Hoang, Francisco Perez-Pomares, Paul H. Blum

School of Biological Sciences: Faculty Publications

Sulfolobus solfataricus secretes an acid-resistant _-amylase (amyA) during growth on starch as the sole

carbon and energy source. Synthesis of this activity is subject to catabolite repression. To better understand

_-amylase function and regulation, the structural gene was identified and disrupted and the resulting mutant

was characterized. Internal _-amylase peptide sequences obtained by tandem mass spectroscopy were used to

identify the amyA coding sequence. Anti-_-amylase antibodies raised against the purified protein immunoprecipitated

secreted _-amylase activity and verified the enzymatic identity of the sequenced protein. A new

gene replacement method was used to disrupt the amyA coding sequence by …


Single-Cell Protein Profiling Of Wastewater Enterobacterial Communities Predicts Disinfection Efficiency, Gomathinayagam Ponniah, Han Chen, Ronda Michielutti, Nancy Salonen, Paul H. Blum Jan 2003

Single-Cell Protein Profiling Of Wastewater Enterobacterial Communities Predicts Disinfection Efficiency, Gomathinayagam Ponniah, Han Chen, Ronda Michielutti, Nancy Salonen, Paul H. Blum

School of Biological Sciences: Faculty Publications

The efficiency of enterobacterial disinfection is dependent largely on enterobacterial community physiology. However, the relationship between enterobacterial community physiology and wastewater processing is unclear. The purpose of this study was to investigate this relationship. The influence of wastewater treatment processes on enterobacterial community physiology was examined at the single-cell level by using cultureindependent methods. Intracellular concentrations of two conserved proteins, the growth-related protein Fis and the stationary-phase protein Dps, were analyzed by epifluoresence microscopy of uncultivated cells by using enterobacterial group-specific polyclonal fluorochrome-coupled antibodies. Enterobacterial single-cell community protein profiles were distinct for different types of biological treatment. The differences were …


Large-Scale Cultivation Of Acidophilic Hyperthermophiles For Recovery Of Secreted Proteins, Penny Worthington, Paul H. Blum, Francisco Perez-Pomares, Tom Elthon Jan 2003

Large-Scale Cultivation Of Acidophilic Hyperthermophiles For Recovery Of Secreted Proteins, Penny Worthington, Paul H. Blum, Francisco Perez-Pomares, Tom Elthon

School of Biological Sciences: Faculty Publications

An electric water heater was modified for large-scale cultivation of aerobic acidophilic hyperthermophiles to enable recovery of secreted proteins. Critical changes included thermostat replacement, redesign of the temperature control circuit, and removal of the cathodic anticorrosion system. These alterations provided accurate temperature and pH control. The bioreactor was used to cultivate selected strains of the archaeon Sulfolobus solfataricus and other species within this genus. Reformulation of a basal salts medium facilitated preparation of large culture volumes and eliminated sterilization-induced precipitation of medium components. Substrate induction of synthesis of the S. solfataricus-secreted alpha-amylase during growth in a defined medium …


Putative Subunits Of The Maize Origin Of Replication Recognition Complex Zmorc1±Zmorc5, Xiaohong Witmer, Raul Alvarez-Venegas, Phillip San-Miguel, Olga Danilevskaya, Zoya Avramova Jan 2003

Putative Subunits Of The Maize Origin Of Replication Recognition Complex Zmorc1±Zmorc5, Xiaohong Witmer, Raul Alvarez-Venegas, Phillip San-Miguel, Olga Danilevskaya, Zoya Avramova

School of Biological Sciences: Faculty Publications

The finding in animal species of complexes homologous

to the products of six Saccharomyces cerevisiae

genes, origin of replication recognition

complex (ORC), has suggested that ORC-related

mechanisms have been conserved in all eukaryotes.

In plants, however, the only cloned putative homologs

of ORC subunits are the Arabidopsis ORC2 and

the rice ORC1. Homologs of other subunits of plant

origin have not been cloned and characterized. A

striking observation was the absence from the

Arabidopsis genome of an obvious candidate genehomolog

of ORC4. This fact raised compelling

questions of whether plants, in general, and

Arabidopsis, in particular, may have lost the …


Hyperthermophilic Alpha-Glucosidase Gene And Its Use, Paul Blum Jan 2003

Hyperthermophilic Alpha-Glucosidase Gene And Its Use, Paul Blum

School of Biological Sciences: Faculty Publications

Recombinant, thermostable alpha-glucosidases from archaeal micro-organisms and isolated DNA encoding for such alpha-glucosidases are provided. The isolated DNA is obtained by use of DNA or antibody probes prepared from the DNA encoding S. sulfataricus alpha-glucosidase. Also provided are methods for producing recombinant archaeal thermostable alpha-glucosidase and transformants incorporating thermostable alpha-glucosidase. Autoprocessing of plant tissue through the use of transgenic thermostable glycosyl hydrolases is described.


Multistate Estimates Of Survival And Movement In Relation To Colony Size In The Sociable Weaver, Charles R. Brown, Rita Covas, Mark D. Anderson, Mary Bomberger Brown Jan 2003

Multistate Estimates Of Survival And Movement In Relation To Colony Size In The Sociable Weaver, Charles R. Brown, Rita Covas, Mark D. Anderson, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

We estimated survival and movement probabilities in relation to breeding-colony size in the sociable weaver (Philetairus socius) by using multistate statistical methods, in which survival and movement to time t + 1 is conditional on an individual’s colony size at time t. The sociable weaver is a colonial, cooperatively breeding species that builds a massive communal nest, with colony size ranging from fewer than 20 to more than 500 individuals in some areas. We conducted an 8-year capture/mark/re-capture study of sociable weavers near Kimberley, South Africa. By comparing the fit of different multistate models to our data, we found evidence …


Testis Size Increases With Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown Jan 2003

Testis Size Increases With Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

By using a sample of more than 800 male cliff swallows (Petrochelidon pyrrhonota) that died during a rare climatic event in our Nebraska study area in 1996, we investigated how testis size was related to body size, age, parasite load, a bird’s past colony-size history, and spleen size. Testis volume in-creased with body size. After correcting for body size, testis volume was lowest for birds age 1 and 2 years but did not vary with age for males 3 years old or more. Birds occupying parasite-free (fumigated) colonies had significantly larger testes than did birds at non-fumigated sites. …


Avian Population Trends Within The Evolving Agricultural Landscape Of The Eastern And Central United States, Michael T. Murphy Jan 2003

Avian Population Trends Within The Evolving Agricultural Landscape Of The Eastern And Central United States, Michael T. Murphy

Biology Faculty Publications and Presentations

State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have driven population trends of grassland and shrub habitat birds over the past two decades. The degree to which population trends differed between grassland and shrub habitats was evaluated with respect to migratory and nesting behavior. Grassland birds declined significantly between 1980 and 1999, but, on average, shrub habitat species did not. Grassland-breeding, long-distance migrants exhibited the strongest negative trends. Most species (78%; n = 63) exhibited at least one significant …


Algal Composition And Abundance In The Neuston Surface Micro Layer From A Lake And Pond In Virginia (U.S.A.), Lubomira Burchardt, Harold G. Marshall Jan 2003

Algal Composition And Abundance In The Neuston Surface Micro Layer From A Lake And Pond In Virginia (U.S.A.), Lubomira Burchardt, Harold G. Marshall

Biological Sciences Faculty Publications

A comparative study was conducted that characterized the algae within the neuston, ca 2 mm below the surface, and the algae in the water column from two freshwater habitats. There were significant differences in total algal abundance and the abundance of diatoms, cyanoprokaryotes, and chlorophytes between the neuston and water column algae of these two regions during each season and at both sites. The pond neuston was dominated by chlorophytes, with total algal abundance ranging seasonally from 0.6 to 59.6 x 10-3 cells ml-1 compared to water column algal concentrations of 4.1 to 40.4 x 10-3 cells ml-1. …


Leptodactylus Mystacinus, M. M. Heyer, W. R. Heyer, Rafael O. De Sá Jan 2003

Leptodactylus Mystacinus, M. M. Heyer, W. R. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus mystacinus are of moderate size, the head is as wide as long, and the hind limbs are moderately short (see Table; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally or at best are weakly expanded laterally and slightly darker than female throats. Male snouts are more spatulate than those of females. Male forearms are not hypertrophied. Males lack asperities on the thumbs and chest. One or two pairs of dorsolateral folds (indicated by dark/light outlining in indifferently preserved specimens) are present: one …


The Reactive Genome, Scott F. Gilbert Jan 2003

The Reactive Genome, Scott F. Gilbert

Biology Faculty Works

No abstract provided.


The Role Of Predator-Induced Polyphenism In The Evolution Of Cognition: A Baldwinian Speculation, Scott F. Gilbert Jan 2003

The Role Of Predator-Induced Polyphenism In The Evolution Of Cognition: A Baldwinian Speculation, Scott F. Gilbert

Biology Faculty Works

No abstract provided.


Regression Approaches For Microarray Data Analysis, Mark R. Segal, Kam D. Dahlquist, Bruce R. Conklin Jan 2003

Regression Approaches For Microarray Data Analysis, Mark R. Segal, Kam D. Dahlquist, Bruce R. Conklin

Biology Faculty Works

A variety of new procedures have been devised to handle the two sample comparison (e.g., tumor versus normal tissue) of gene expression values as measured with microarrays. Such new methods are required in part because of some defining characteristics of microarray-based studies: (i) the very large number of genes contributing expression measures which far exceeds the number of samples (observations) available, and (ii) the fact that by virtue of pathway/network relationships, the gene expression measures tend to be highly correlated. These concerns are exacerbated in the regression setting, where the objective is to relate gene expression, simultaneously for multiple genes, …


Mappfinder: Using Gene Ontology And Genmapp To Create A Global Gene-Expression Profile From Microarray Data, Scott W. Doniger, Nathan Salomonis, Kam D. Dahlquist, Karen Vranizan, Steven C. Lawlor, Bruce R. Conklin Jan 2003

Mappfinder: Using Gene Ontology And Genmapp To Create A Global Gene-Expression Profile From Microarray Data, Scott W. Doniger, Nathan Salomonis, Kam D. Dahlquist, Karen Vranizan, Steven C. Lawlor, Bruce R. Conklin

Biology Faculty Works

MAPPFinder is a tool that creates a global gene-expression profile across all areas of biology by integrating the annotations of the Gene Ontology (GO) Project with the free software package GenMAPP (http://www.GenMAPP.org). The results are displayed in a searchable browser, allowing the user to rapidly identify GO terms with over-represented numbers of geneexpression changes. Clicking on GO terms generates GenMAPP graphical files where gene relationships can be explored, annotated, and files can be freely exchanged.


Thicker Than Blood: Conserved Mechanisms In Drosophila And Vertebrate Hematopoiesis, Cory J. Evans, Volker Hartenstein, Utpal Banerjee Jan 2003

Thicker Than Blood: Conserved Mechanisms In Drosophila And Vertebrate Hematopoiesis, Cory J. Evans, Volker Hartenstein, Utpal Banerjee

Biology Faculty Works

Blood development in Drosophila melanogaster shares several interesting features with hematopoiesis in vertebrates, including spatiotemporal regulation as well as the use of similar transcriptional regulators and signaling pathways. In this review, we describe what is known about hematopoietic development in Drosophila and the various cell types generated and their functions. Additionally, the molecular genetic mechanisms of hematopoietic cell fate determination and commitment within Drosophila blood cell lineages are discussed and compared to vertebrate mechanisms.


"Autapomorphies Of The Endophragmal System In Trichodactylid Freshwater Crabs" , Richard V. Sternberg, Neil Cumberlidge Jan 2003

"Autapomorphies Of The Endophragmal System In Trichodactylid Freshwater Crabs" , Richard V. Sternberg, Neil Cumberlidge

Journal Articles

No abstract provided.


"Les Crustacés Décapodes Du Nimba Et Sa Région" , Neil Cumberlidge, Denise Huguet Jan 2003

"Les Crustacés Décapodes Du Nimba Et Sa Région" , Neil Cumberlidge, Denise Huguet

Journal Articles

No abstract provided.


Life History Characteristics Of Placental Nonvolant Mammals, S.K. Morgan Ernest Jan 2003

Life History Characteristics Of Placental Nonvolant Mammals, S.K. Morgan Ernest

Biology Faculty Publications

The purpose of this data set was to compile general life history characteristics for a variety of mammalian species in order to perform comparative life history analyses among different taxa and different body size groups. Data were collected from the literature, and data sources are documented for each species within the data file. Since life history characteristics will show minor variation with environmental conditions (resource availability, climate, competitive environment, and predation pressure) a general life history for each species was sought to average over minor differences in local populations. To create a general life history for each species, life history …


Body Mass Of Late Quaternary Mammals, F. A. Smith, S. K. Lyons, S.K. Morgan Ernest, K. E. Jones, D. M. Kaufman, T. Dayan, P. A. Marquet, J. P. Haskell Jan 2003

Body Mass Of Late Quaternary Mammals, F. A. Smith, S. K. Lyons, S.K. Morgan Ernest, K. E. Jones, D. M. Kaufman, T. Dayan, P. A. Marquet, J. P. Haskell

Biology Faculty Publications

The purpose of this data set was to compile body mass information for all mammals on Earth so that we could investigate the patterns of body mass seen across geographic and taxonomic space and evolutionary time. We were interested in the heritability of body size across taxonomic groups (How conserved is body mass within a genus, family, and order?), in the overall pattern of body mass across continents (Do the moments and other descriptive statistics remain the same across geographic space?), and over evolutionary time (How quickly did body mass patterns iterate on the patterns seen today? Were the Pleistocene …


First Nesting Attempt Of Yellow-Faced Grassquit (Tiaris Olivacea) In The United States, Timothy Brush Jan 2003

First Nesting Attempt Of Yellow-Faced Grassquit (Tiaris Olivacea) In The United States, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

No abstract provided.


Improving Quantitative Understanding Using Spreadsheet Models, Michelle A. Baker Jan 2003

Improving Quantitative Understanding Using Spreadsheet Models, Michelle A. Baker

Biology Faculty Publications

No abstract provided.


Mosquitoes, West Nile Virus, Attractants, Competition, Environmental Conditions, And Insecticide Resistance, Alan Bradley Wells Jan 2003

Mosquitoes, West Nile Virus, Attractants, Competition, Environmental Conditions, And Insecticide Resistance, Alan Bradley Wells

College of Graduate Studies: Theses & Dissertations (1964–2006)

The six main objectives of this project were: 1) test for levels of West Nile Virus in mosquitoes collected at a Fulton County Recreational Facility, 2) assay various mosquito oviposition attractants on West Nile virus positive female mosquitoes, 3) test effects of distance between mosquito infusion attractants, 4) determine effects of study site location, treatment, and competition distances on mosquito collections, 5) test for any correlation between environmental factors and mosquito abundance, and 6) measure levels of enzymatic insecticide resistance present in species of female mosquitoes that tested positive for the presence of West Nile Virus. Ofthe two species that …


Detecting Stress In Glasshouse Plants Using Color Infrared Imagery: A Potential New Application For Remote Sensing, Kenneth R. Summy, Christopher R. Little, Ruben A. Mazariegos, James H. Everitt, M. R. Davis, J. V. French, A. W. Scott Jr. Jan 2003

Detecting Stress In Glasshouse Plants Using Color Infrared Imagery: A Potential New Application For Remote Sensing, Kenneth R. Summy, Christopher R. Little, Ruben A. Mazariegos, James H. Everitt, M. R. Davis, J. V. French, A. W. Scott Jr.

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

English: Studies were conducted to evaluate the effectiveness of color infrared (CIR) film for detecting physiological stress in plants located within glasshouse structures. Spectroradiometer measurements obtained within and outside of a structure constructed of polycarbonate plastic indicated no significant attenuation or disruption of visible and near-infrared radiation entering the structure. CIR photographs of cucumber seedlings (Cucumis sativus) obtained within the greenhouse were comparable in quality to those obtained outside the structure, and clearly distinguished between foliage of healthy plants and those subjected to a moderate level of nitrogen stress. In CIR imagery of a trifoliate orange tree (Poncirus trifoliata (L.) …


Effects Of Social Interaction On The Electric Organ Discharge In A Mormyrid Fish, Gnathonemus Petersii (Mormyridae, Teleostei), Thomas A. Terleph, Peter Moller Jan 2003

Effects Of Social Interaction On The Electric Organ Discharge In A Mormyrid Fish, Gnathonemus Petersii (Mormyridae, Teleostei), Thomas A. Terleph, Peter Moller

Biology Faculty Publications

African weakly discharging electric fish (Mormyridae) use their self-generated electric signals and electroreceptive abilities for orientation and communication in the context of courtship and territorial interactions. This paper documents socially mediated changes in the electric organ discharge (EOD) of subadult Gnathonemus petersii under non-breeding environmental conditions. Increases in EOD duration and changes in the relative phase amplitudes occurred in dominant fish during same-sex (male–male, female–female) and opposite-sex interactions. Similar changes were also observed in fish that were restricted in their physical interactions, suggesting that direct contact is not necessary to induce dominance-typical EOD waveforms. The possible communicative functions of these …


Effects Of Pesticides And Their Combinations On Human Fibroblast Cells, Yijun Deng Jan 2003

Effects Of Pesticides And Their Combinations On Human Fibroblast Cells, Yijun Deng

Dissertations and Theses @ UNI

Pesticides are widely used in Iowa due to its primarily agricultural economy. Many studies have shown that the water sources in Iowa are contaminated by multiple pesticides. Most of the information about the adverse human health effects due to such environmental contaminants comes from studies that focus on exposure to single rather than multiple pesticides. Additionally, many of the environmental regulations regarding levels of pesticide contamination refer only to single, individual pesticides. Many questions remain about the human health effects of exposure to pesticide combinations. This study attempts to understand the effects of pesticide combinations on human cells. A cell …


Comparative Serological And Molecular Analysis Of Group Viii Spiroplasma From Australia And North America, April Carmita Murphy Jan 2003

Comparative Serological And Molecular Analysis Of Group Viii Spiroplasma From Australia And North America, April Carmita Murphy

College of Graduate Studies: Theses & Dissertations (1964–2006)

Spiroplasma bacteria (Mollicutes: Spiroplasmataceae) are characterized by motility, helical morphology and are most frequently found in insect guts and phloem tubes of plants. Traditionally, Spiroplasma have been classified by serology. Recent work has generated 16S rDNA sequences that generally correlate with the serological findings. Although the serology and the 16S rDNA sequence analysis clearly classifies strains to the group level, they do not distinguish between strains within the same group. The goal of this project was to investigate the utility of the 16S-23S rDNA intergenic spacer region sequence as a means to distinguish these closely related strains.

We chose Group …


Perfecting The Match: The Visual Economy Of Egg Donation, Katherine M. Boulay Jan 2003

Perfecting The Match: The Visual Economy Of Egg Donation, Katherine M. Boulay

Doctoral

This thesis is a response to the absence of discussion in feminist and cultural studies of Assisted Reproductive Technology’s (ART) increasing utilisation of visuality and technology as complementary legitimating discourses. While critiques of the epistemologies and practices undergirding ART point to the fact that imaging technologies are used to reveal knowledge held in bodies, lacking in current theoretical work on ART, however, is an ethnographic engagement with how visual technologies actually produce the internal and externalscapes of these bodies, and knowledges about them. Mapping selective visual knowledges and technologies constitutive of the ART egg donation, the thesis engages with disparate …


Identification Of Asteroid Genera With Species Capable Of Larval Cloning, K. E. Knott, E. J. Balser, William Jaeckle Jan 2003

Identification Of Asteroid Genera With Species Capable Of Larval Cloning, K. E. Knott, E. J. Balser, William Jaeckle

Scholarship

Asexual reproduction in larvae, larval cloning, is a recently recognized component of the complex life histories of asteroids. We compare DNA sequences of mitochondrial tRNA genes (Ala, Leu, Asn, Pro and Gln) from larvae in the process of cloning collected in the field with sequences from adults of known species in order to identify asteroid taxa capable of cloning. Neighbor-joining analysis identified four distinct groups of larvae, each having no, or very little, sequence divergence (p distances ranging from 0.00000 to 0.02589); thus, we conclude that each larval group most likely represents a single species. These field-collected larvae cannot …


Assessment Of Wind Energy Potential For Eletricity Generation In Setchet, Hanang, Tanzania, A. S. Kasasi, R. M. Kainkwa Dec 2002

Assessment Of Wind Energy Potential For Eletricity Generation In Setchet, Hanang, Tanzania, A. S. Kasasi, R. M. Kainkwa

Tanzania Journal of Science

Tanzania depends heavily on hydropower for her electricity demand and experiences power shortage during the dry seasons. Wind energy is proposed as an alternative source of electricity to the fossil fuel generators during the dry season, the latter are normally used to supplement the shortfall in hydro-electricity generation. Fossil fuel generators produce emissions that are toxic and as such degrade the environment. Wind speed data from a site called Setchet is used to illustrate that the available wind energy can be harvested to generate electricity that can supplement the shortfall of electricity. The windy season, which is from July to …


Morphometrics Of The Pancake Tortoise (Malacochersus Tornieri) In Tanzania, J. Kabigumila Dec 2002

Morphometrics Of The Pancake Tortoise (Malacochersus Tornieri) In Tanzania, J. Kabigumila

Tanzania Journal of Science

Observations were made of the morphometrics of captive pancake tortoise (Malacochersus tornieri) in June 1995. Carapace length ranges for immature tortoises and adult males and females were 50-115, 123-160 and 129-171 mm respectively. The respective carapace widths were 45-90, 97-130, and 92-129 and 97-130 mm. Carapace height ranges were 15-29, 25-40 and 117-159 mm, respectively, while plastron length ranges were 45-110, 108-150 and 117-159 mm. The relationships between carapace length and width (males: y = 13.763+0.639x; females: y = 17.302+0.639x) and height (males: y=6.851+0.170x, females: y = 17.274+0.170x) were isometric and sexually dimorphic in adults. The relationship between carapace length …