Life Sciences Commons^™

Expression Of Acetate Permease-Like (Apl) Genes In Subsurface Communities Of Geobacter Species Under Fluctuating Acetate Concentrations, Derek Lovley, Hila Elifantz, Lucie N'Guessan, Paula Mouser, Kenneth Williams, Michael Wilkins, Carla Risso, Dawn Holmes, Philip Long

Carla Risso

The addition of acetate to uranium-contaminated aquifers in order to stimulate the growth and activity of Geobacter species that reduce uranium is a promising in situ bioremediation option. Optimizing this bioremediation strategy requires that sufficient acetate be added to promote Geobacter species growth. We hypothesized that under acetate-limiting conditions, subsurface Geobacter species would increase the expression of either putative acetate symporters genes (aplI and aplII). Acetate was added to a uranium-contaminated aquifer (Rifle, CO) in two continuous amendments separated by 5 days of groundwater flush to create changing acetate concentrations. While the expression of aplI in monitoring well D04 (high …

From Structure To Function: The Ecology Of Host-Associated Microbial Communities, Courtney Jaime Robinson, Brendan J M Bohannan, Vincent Bensan Young

Courtney Robinson

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael Lombardo, Patrick Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. Zeller

Michael P Lombardo

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.

Access To Mutualistic Endosymbiotic Microbes: An Underappreciated Benefit Of Group Living, Michael Lombardo

Michael P Lombardo

"The original publication is available at www.springerlink.com"

A central question in behavioral ecology has been why animals live in groups. Previous theories about the evolution of sociality focused on the potential benefits of decreased risk of predation, increased foraging or feeding efficiency, and mutual aid in defending resources and/or rearing offspring. This paper argues that access to mutualistic endosymbiotic microbes is an underappreciated benefit of group living and sets out to reinvigorate Troyer’s hypothesis that the need to obtain cellulolytic microbes from conspecifics influenced the evolution of social behavior in herbivores and to extend it to nonherbivores. This extension is …

Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara Mills, Michael Lombardo, Patrick Thorpe

Michael P Lombardo

Microbes have the potential to be important selective forces in many aspects of avian biology. Microbes can affect fitness as a result of either their pathogenic or beneficial effects on host health. Little is known about the chronology of microbial colonization of nestlings or the effects of microbes on fledgling condition. We set out to (1) characterize the time course of microbial colonization of the cloacae of nestling Tree Swallows (Tachycineta bicolor), (2) examine the relationship between cloacal microbes and fledgling condition, and (3) determine if nest mates had similar assemblages of cloacal microbes. We repeatedly measured nestlings and sampled …

On The Evolution Of Sexually Transmitted Diseases In Birds, Michael Lombardo

Michael P Lombardo

"The definitive version is available at www.blackwell-synergy.com".

Sexually transmitted diseases (STDs) in animals are caused by pathogens that are transmitted during copulation. Birds have played an important role in the development of STD-centered theories of mating behavior. However, it is not known whether STDs exist in wild bird populations. While the avian cloaca with its dual functions of gamete transfer and excretion seemingly predisposes birds for the evolution of STDs, the life history patterns of most birds (i.e., seasonal breeders with relatively brief annual periods of sexual activity) suggest otherwise. The importance of STDs as selective forces that shape host …

The Beneficial Sexually Transmitted Microbe Hypothesis Of Avian Copulation, Michael Lombardo, Patrick Thorpe, Harry Power

Michael P Lombardo

Several hypotheses have been proposed to explain why female birds either copulate repeatedly with a single mate or copulate with multiple partners even though only a single copulation may be sufficient to fertilize an entire clutch. We hypothesize that females may directly benefit from high frequencies of copulation and multiple copulation partners if they receive a cloacal inoculation of beneficial sexually transmitted microbes (STMs) that can either protect them against future encounters with pathogens and/or serve as therapy against present infections. Experiments in domestic animal production, wildlife rehabilitation, and clinical medicine indicate that inoculations of beneficial microbes derived from the …

Molecular Probes For The Detection Of Cyanophage As-1 And Its Cyanobacterial Hosts., Tin-Chun Chu, Jonathan Jimenez, Lauren Strawn, Michelle Reed, Lauren Pohren, Lee Lee

Tin-Chun Chu, Ph.D.

No abstract provided.

Antibiotic Administration Alters The Community Structure Of The Gastrointestinal Micobiota, Courtney Jaime Robinson, Vincent Bensan Young

Courtney Robinson

Elevated Tumor Necrosis Factor Alpha Production Concomitant To Elevated Prostaglandin E2 Production By Trauma Patients' Monocytes, Thomas Takayama, Carol Miller-Graziano, Gyongyi Szabo

Gyongyi Szabo

The level of tumor necrosis factor alpha (TNF alpha), a monokine implicated in mediating septic shock, is elevated in the blood of some patients with sepsis. Monocytes from 11 trauma patients and 11 burn patients were suboptimally stimulated with interferon gamma and muramyl dipeptide, an analogue of bacterial wall products. The patients with sepsis showed significantly greater total TNF alpha levels (secreted in combination with cell-associated) 3 days before septic episodes, as compared with normal controls (32.38 to 2231.76 ng/10(6) monocytes per milliliter, median = 121.03 ng/10(6) monocytes per milliliter; normal control: 0.00 to 18.20 ng/10(6) monocytes per milliliter, median …

Hepatitis C Core And Nonstructural 3 Proteins Trigger Toll-Like Receptor 2-Mediated Pathways And Inflammatory Activation, Angela Dolganiuc, Shilpa Oak, Karen Kodys, Douglas Golenbock, Robert Finberg, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND AND AIMS: Recent evidence suggests that toll-like receptors (TLRs) recognize certain viruses. We reported that hepatitis C virus (HCV) core and nonstructural 3 (NS3) proteins activate inflammatory pathways in monocytes. The aim of this study was to investigate the role of TLRs in innate immune cell activation by core and NS3 proteins. METHODS: Human monocytes, human embryonic kidney cells transfected with TLR2, and peritoneal macrophages from TLR2, MyD88 knockout, and wild-type mice were studied to determine intracellular signaling and proinflammatory cytokine induction by HCV proteins. RESULTS: HCV core and NS3 proteins triggered inflammatory cell activation via the pattern recognition …

Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Jasminum Sambac From Djibouti, Fatou Abdoul-Latif, Prosper Edou, François Eba, Nabil Mohamed, Adwa Ali, Samatar Djama, Louis-Clément Obame, Mamoudou Hama Dicko

Pr. Mamoudou H. DICKO, PhD

The essential oil of jasminum sambac from Djibouti was subjected to screening for their possible antioxidant activity by two complementary test systems, namely DPPH free radical scavenging and beta-carotene-linoleic acid assays. Butylated hydroxytoluene (BHT) was used as positive control in both test systems. In the DPPH test system, the IC50 value of essential oil and methanol extract were respectively 7.43 and 2.30 μg/ml. In the beta-carotene-linoleic acid system, oxidation was effectively inhibited by Jasminum sambac, the RAA value of essential oil and methanol extract were respectively 96.6 and 93.9%. When compared to BHT, the essential oil and methanol extract had …

Early Cranial Patterning In The Direct-Developing Frog Eleutherodactylus Coqui Revealed Through Gene Expression, Ryan Kerney, Joshua Gross, James Hanken

Ryan Kerney

Genetic and developmental alterations associated with the evolution of amphibian direct development remain largely unexplored. Specifically, little is known of the underlying expression of skeletal regulatory genes, which may reveal early modifications to cranial ontogeny in direct-developing species. We describe expression patterns of three key skeletal regulators (runx2, sox9, and bmp4) along with the cartilage-dominant collagen 2a1 gene (col2a1) during cranial development in the direct- developing anuran, Eleutherodactylus coqui. Expression patterns of these regulators reveal transient skeletogenic anlagen that correspond to larval cartilages, but which never fully form in E. coqui. Suprarostral anlagen in the frontonasal processes are detected through …

The Chitobiose Transporter, Chbc, Is Required For Chitin Utilization In Borrelia Burgdorferi, David Nelson

David R. Nelson

Background: The bacterium Borrelia burgdorferi, the causative agent of Lyme disease, is a limited-genome organism that must obtain many of its biochemical building blocks, including N-acetylglucosamine (GlcNAc), from its tick or vertebrate host. GlcNAc can be imported into the cell as a monomer or dimer (chitobiose), and the annotation for several B. burgdorferi genes suggests that this organism may be able to degrade and utilize chitin, a polymer of GlcNAc. We investigated the ability of B. burgdorferi to utilize chitin in the absence of free GlcNAc, and we attempted to identify genes involved in the process. We also examined the …

The Genome Of Geobacter Bemidjiensis, Exemplar For The Subsurface Clade Of Geobacter Species That Predominate In Fe(Iii)-Reducing Subsurface Enviorments, Derek Lovley, Muktak Aklujkar, Nealson Young, Dawn Holmes, Milind Chavan, Carla Risso, Hajnalka Kiss, Cliff Han, Miriam Land

Muktak Aklujkar

BACKGROUND: Geobacter species in a phylogenetic cluster known as subsurface clade 1 are often the predominant microorganisms in subsurface environments in which Fe(III) reduction is the primary electron-accepting process. Geobacter bemidjiensis, a member of this clade, was isolated from hydrocarbon-contaminated subsurface sediments in Bemidji, Minnesota, and is closely related to Geobacter species found to be abundant at other subsurface sites. This study examines whether there are significant differences in the metabolism and physiology of G. bemidjiensis compared to non-subsurface Geobacter species. RESULTS: Annotation of the genome sequence of G. bemidjiensis indicates several differences in metabolism compared to previously sequenced non-subsurface …

Video: Body Languages: Choreographing Biology, Katja Kolcio

Katja Kolcio Ph.D.

Co-taught by professors Manju Hingorani and Katja Kolcio at Wesleyan University, this course was an introduction to human biology. From scientific and choreographic perspectives, students practiced movement awareness and learned basic principles of choreography, and applied these skills to the exploration of human biology. Manju Hingorani, Professor of Molecular Biology and Biochemistry Katja Kolcio, Associate Professor of Dance and Environmental Studies

Contributions Of Francisella Tularensis Subsp. Novicida Chitinases And Sec Secretion System To Biofilm Formation On Chitin, Jeffrey J. Margolis, Sahar H. El-Etr, Lydia-Marie Joubert, Emily Moore, Richard Robinson, Amy Rasley, Alfred M. Spormann, Denise M. Monack

Jeffrey Margolis

Indigenous Ectosymbiotic Bacteria Associated With Diverse Hydrothermal Vent Invertebrates, Shana K. Goffredi

Shana Goffredi

Symbioses involving bacteria and invertebrates contribute to the biological diversity and high productivity of both aquatic and terrestrial environments. Well-known examples from chemosynthetic deep-sea hydrothermal vent environments involve ectosymbiotic microbes associated with the external surfaces of marine invertebrates. Some of these ectosymbioses confer protection or defence from predators or the environment itself, some are nutritional in nature, and many still are of unknown function. Several recently discovered hydrothermal vent invertebrates, including two populations of yeti crab (Kiwa spp.), a limpet (Symmetromphalus aff. hageni), and the scaly-foot snail (as yet undescribed), support a consortium of diverse bacteria. Comparisons of these ectosymbioses …

Interference With Histidyl-Trna Synthetase By A Crispr Spacer Sequence As A Factor In The Evolution Of Pelobacter Carbinolicus, Derek Lovley, Muktak Aklujkar

Muktak Aklujkar

BACKGROUND: Pelobacter carbinolicus, a bacterium of the family Geobacteraceae, cannot reduce Fe(III) directly or produce electricity like its relatives. How P. carbinolicus evolved is an intriguing problem. The genome of P. carbinolicus contains clustered regularly interspaced short palindromic repeats (CRISPR) separated by unique spacer sequences, which recent studies have shown to produce RNA molecules that interfere with genes containing identical sequences. RESULTS: CRISPR spacer #1, which matches a sequence within hisS, the histidyl-tRNA synthetase gene of P. carbinolicus, was shown to be expressed. Phylogenetic analysis and genetics demonstrated that a gene paralogous to hisS in the genomes of Geobacteraceae is …

Synthetic Genome: Now That We’Re Creators, What Should We Create?, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.

The Ecology Of Speciation In Bacillus, Nora Connor, Johannes Sikorski, Alejandro P. Rooney, Sarah Kopac, Alexander F. Koeppel, Andrew Burger, Scott G. Cole, Elizabeth B. Perry, Danny Krizanc, Nicholas C. Field, Michele Slaton, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.

The Genome Of Geobacter Bemidjiensis, Exemplar For The Subsurface Clade Of Geobacter Species That Predominate In Fe(Iii)-Reducing Subsurface Enviorments, Derek Lovley, Muktak Aklujkar, Nealson D. Young, Dawn Holmes, Milind Chavan, Carla Risso, Hajnalka E. Kiss, Cliff S. Han, Miriam L. Land

Carla Risso

BACKGROUND: Geobacter species in a phylogenetic cluster known as subsurface clade 1 are often the predominant microorganisms in subsurface environments in which Fe(III) reduction is the primary electron-accepting process. Geobacter bemidjiensis, a member of this clade, was isolated from hydrocarbon-contaminated subsurface sediments in Bemidji, Minnesota, and is closely related to Geobacter species found to be abundant at other subsurface sites. This study examines whether there are significant differences in the metabolism and physiology of G. bemidjiensis compared to non-subsurface Geobacter species. RESULTS: Annotation of the genome sequence of G. bemidjiensis indicates several differences in metabolism compared to previously sequenced non-subsurface …

Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan Kerney, Brian K. Hall, James Hanken

Ryan Kerney

This study characterizes regulatory elements of collagen 2α1 (col2a1) in Xenopus that enable transgene expression in cartilage-forming chondrocytes. The reporters described in this study drive strong cartilage-specific gene expression, which will be a valuable tool for further investigations of Xenopus skeletal development. While endogenous col2a1 mRNA is expressed in many embryonic tissues, its expression becomes restricted to tadpole and adult chondrocytes. This chondrocyte-specific expression is recapitulated by col2a1 reporter constructs, which were tested through I-SceI meganuclease-mediated transgenesis. These constructs contain a portion of the Xenopus tropicalis col2a1 intron, which aligns to a cartilage-specific intronic enhancer that has been well characterized …