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Possible Nonconductive Role Of Geobacter Sulfurreducens Pilus Nanowires In Biofilm Formation, Gemma Reguera, Rachael B. Pollina, Julie S. Nicoll, Derek Lovley

Derek Lovley

Geobacter sulfurreducens required expression of electrically conductive pili to form biofilms on Fe(III) oxide surfaces, but pili were also essential for biofilm development on plain glass when fumarate was the sole electron acceptor. Furthermore, pili were needed for cell aggregation in agglutination studies. These results suggest that the pili of G. sulfurreducens also have a structural role in biofilm formation.

Bmc Infectious Diseases, Frances Cirino, Wilmore C. Webley, Corrie West, Nancy L. Croteau, Chester Andrzejewski Jr, Elizabeth S. Stuart

Wilmore C Webley

No abstract provided.

A Genomic Approach To Identify Regulatory Nodes In The Transcriptional Network Of Systemic Acquired Resistance In Plants, Dong Wang, Nita Amornsiripanitch, Xinnian Dong

Dong Wang

Many biological processes are controlled by intricate networks of transcriptional regulators. With the development of microarray technology, transcriptional changes can be examined at the whole-genome level. However, such analysis often lacks information on the hierarchical relationship between components of a given system. Systemic acquired resistance (SAR) is an inducible plant defense response involving a cascade of transcriptional events induced by salicylic acid through the transcription cofactor NPR1. To identify additional regulatory nodes in the SAR network, we performed microarray analysis on Arabidopsis plants expressing the NPR1-GR (glucocorticoid receptor) fusion protein. Since nuclear translocation of NPR1-GR requires dexamethasone, we were able …

Reconstitution Of Protein Targeting To The Inner Envelope Membrane Of Chloroplasts, Ming Li, Danny Schnell

Danny Schnell

The chloroplast envelope plays critical roles in the synthesis and regulated transport of key metabolites, including intermediates in photosynthesis and lipid metabolism. Despite this importance, the biogenesis of the envelope membranes has not been investigated in detail. To identify the determinants of protein targeting to the inner envelope membrane (IM), we investigated the targeting of the nucleus-encoded integral IM protein, atTic40. We found that pre-atTic40 is imported into chloroplasts and processed to an intermediate size (int-atTic40) before insertion into the IM. Int-atTic40 is soluble and inserts into the IM from the internal stromal compartment. We also show that atTic40 and …

Role Of Red Gsu In Stress Response And Fe(Iii) Reduction In Geobacter Sulfurreducens, Laurie N. Didonato, Sara A. Sullivan, Barbara A. Methѐ, Kelly P. Nevin, Reg England, Derek Lovley

Kelly Nevin

Geobacter species are key members of the microbial community in many subsurface environments in which dissimilatory metal reduction is an important process. The genome of Geobacter sulfurreducens contains a gene designated relGsu, which encodes a RelA homolog predicted to catalyze both the synthesis and the degradation of guanosine 3′,5′-bispyrophosphate (ppGpp), a regulatory molecule that signals slow growth in response to nutrient limitation in bacteria. To evaluate the physiological role of RelGsu in G. sulfurreducens, a relGsu mutant was constructed and characterized, and ppGpp levels were monitored under various conditions in both the wild-type and relGsu mutant strains. In the wild-type …

Role Of Red Gsu In Stress Response And Fe(Iii) Reduction In Geobacter Sulfurreducens, Laurie N. Didonato, Sara A. Sullivan, Barbara A. Methѐ, Kelly P. Nevin, Reg England, Derek Lovley

Derek Lovley

Geobacter species are key members of the microbial community in many subsurface environments in which dissimilatory metal reduction is an important process. The genome of Geobacter sulfurreducens contains a gene designated relGsu, which encodes a RelA homolog predicted to catalyze both the synthesis and the degradation of guanosine 3′,5′-bispyrophosphate (ppGpp), a regulatory molecule that signals slow growth in response to nutrient limitation in bacteria. To evaluate the physiological role of RelGsu in G. sulfurreducens, a relGsu mutant was constructed and characterized, and ppGpp levels were monitored under various conditions in both the wild-type and relGsu mutant strains. In the wild-type …

Implicating An Introduced Generalist Parasitoid In The Invasive Browntail Moth's Enigmatic Demise, Joseph Elkinton, D. Parry, G. Boettner

Joseph Elkinton

Recent attention has focused on the harmful effects of introduced biological control agents on nontarget species. The parasitoid Compsilura concinnata is a notable example of such biological control gone wrong. Introduced in 1906 primarily for control of gypsy moth, Lymantria dispar, this tachinid fly now attacks more than 180 species of native Lepidoptera in North America. While it did not prevent outbreaks or spread of gypsy moth, we present reanalyzed historical data and experimental findings suggesting that parasitism by C. concinnata is the cause of the enigmatic near-extirpation of another of North America's most successful invaders, the browntail moth (Euproctis …

Cardiac Myosin Missense Mutations Cause Dilated Cardiomyopathy In Mouse Models And Depress Molecular Motor Function, Joachim Schmitt, Edward Debold, Ferhaan Ahmad, Amy Armstrong, Andrea Frederico, David Conner, Ulrike Mende, Martin Lohse, David Warshaw, Christine Seidman, J. Seidman

Edward P. Debold

Dilated cardiomyopathy (DCM) leads to heart failure, a leading cause of death in industrialized nations. Approximately 30% of DCM cases are genetic in origin, with some resulting from point mutations in cardiac myosin, the molecular motor of the heart. The effects of these mutations on myosin's molecular mechanics have not been determined. We have engineered two murine models characterizing the physiological, cellular, and molecular effects of DCM-causing missense mutations (S532P and F764L) in the α-cardiac myosin heavy chain and compared them with WT mice. Mutant mice developed morphological and functional characteristics of DCM consistent with the human phenotypes. Contractile function …

The Structure Of Escherichia Coli Signal Recognition Particle Revealed By Scanning Transmission Electron Microscopy, Lain L. Mainprize, Daniel R. Beniac, Elena Falkovskaia, Robert M. Cleverley, Lila Gierasch, F. Peter Ottensmeyer, David W. Andrews

Lila Gierasch

Structural studies on various domains of the ribonucleoprotein signal recognition particle (SRP) have not converged on a single complete structure of bacterial SRP consistent with the biochemistry of the particle. We obtained a three-dimensional structure for Escherichia coli SRP by cryoscanning transmission electron microscopy and mapped the internal RNA by electron spectroscopic imaging. Crystallographic data were fit into the SRP reconstruction, and although the resulting model differed from previous models, they could be rationalized by movement through an interdomain linker of Ffh, the protein component of SRP. Fluorescence resonance energy transfer experiments determined interdomain distances that were consistent with our …

Biofilm And Nanowire Production Leads To Increased Current In Geobacter Sulfurreducens Fuel Cells, Gemma Reguera, Kelly P. Nevin, Julie S. Nicoll, Sean F. Covalla, Trevor L. Woodard, Derek Lovley

Derek Lovley

Geobacter sulfurreducens developed highly structured, multilayer biofilms on the anode surface of a microbial fuel cell converting acetate to electricity. Cells at a distance from the anode remained viable, and there was no decrease in the efficiency of current production as the thickness of the biofilm increased. Genetic studies demonstrated that efficient electron transfer through the biofilm required the presence of electrically conductive pili. These pili may represent an electronic network permeating the biofilm that can promote long-range electrical transfer in an energy-efficient manner, increasing electricity production more than 10-fold.

Biofilm And Nanowire Production Leads To Increased Current In Geobacter Sulfurreducens Fuel Cells, Gemma Reguera, Kelly P. Nevin, Julie S. Nicoll, Sean F. Covalla, Trevor L. Woodard, Derek Lovley

Kelly Nevin

Geobacter sulfurreducens developed highly structured, multilayer biofilms on the anode surface of a microbial fuel cell converting acetate to electricity. Cells at a distance from the anode remained viable, and there was no decrease in the efficiency of current production as the thickness of the biofilm increased. Genetic studies demonstrated that efficient electron transfer through the biofilm required the presence of electrically conductive pili. These pili may represent an electronic network permeating the biofilm that can promote long-range electrical transfer in an energy-efficient manner, increasing electricity production more than 10-fold.

A Comprehensive Structure–Function Analysis Of Arabidopsis Sni1 Defines Essential Regions And Transcriptional Repressor Activity, Rebecca A. Mosher, Wendy E. Durrant, Dong Wang, Jungi Song, Xinnian Dong

Dong Wang

The expression of systemic acquired resistance (SAR) in plants involves the upregulation of many Pathogenesis-Related (PR) genes, which work in concert to confer resistance to a broad spectrum of pathogens. Because SAR is a costly process, SAR-associated transcription must be tightly regulated. Arabidopsis thaliana SNI1 (for Suppressor of NPR1, Inducible) is a negative regulator of SAR required to dampen the basal expression of PR genes. Whole genome transcriptional profiling showed that in the sni1 mutant, Nonexpresser of PR genes (NPR1)–dependent benzothiadiazole S-methylester–responsive genes were specifically derepressed. Interestingly, SNI1 also repressed transcription when expressed in yeast, suggesting that it functions as …

Tests Of Parallel Molecular Evolution In A Long-Term Experiment With Escherichia Coli, Margaret Riley, Robert Woods, Dominique Schneider, Cynthia L. Winkworth, Richard E. Lenski

Margaret Riley

The repeatability of evolutionary change is difficult to quantify because only a single outcome can usually be observed for any precise set of circumstances. In this study, however, we have quantified the frequency of parallel and divergent genetic changes in 12 initially identical populations of Escherichia coli that evolved in identical environments for 20,000 cell generations. Unlike previous analyses in which candidate genes were identified based on parallel phenotypic changes, here we sequenced four loci (pykF, nadR, pbpA-rodA, and hokB/sokB) in which mutations of unknown effect had been discovered in one population, and then we compared the substitution pattern in …

Conference Keynoter Defends Practices Buried In New England’S Agricultural History, Plans For Future, Madeleine K. Charney

Madeleine K. Charney

Brian Donahue, environmental historian, debunks the myths of early New England farming practices.

Conference Keynoter Defends Practices Buried In New England’S Agricultural History, Plans For Future, Madeleine K. Charney

University Libraries Publication Series

Brian Donahue, environmental historian, debunks the myths of early New England farming practices.

Proposal To The Ethics Education In Science And Engineering Program, National Science Foundation: Role-Play Scenarios For Teaching Responsible Conduct Of Research, Michael C. Loui, C. K. Gunsalus

Ethics in Science and Engineering National Clearinghouse

We propose to develop and assess role-play scenarios to teach central topics in the responsible conduct of research (RCR) to graduate students in science and engineering. Together the scenarios will cover plagiarism, authorship, conflict of interest, interpersonal conflicts in mentoring, and concerns about compliance with research regulations on human participants in research, animal subjects, or hazardous substances. Two scenarios will present potential whistleblowing situations.

Intellectual merit: Few previous studies have carefully assessed the effectiveness of role-play in teaching ethics. We will conduct a rigorous, systematic assessment of role-play, using multiple methods, with a diverse group of graduate students. We will …

Belladonna/Lhx2 Is Required For Neural Patterning And Midline Axon Guidance In The Zebrafish Forebrain, Anandita Seth, James Culverwell, Mitchell Walkowicz, Sabrina Toro, Jens M. Rick, Stephan C.F. Neuhauss, Zoltan M. Varga, Rolf O. Karlstrom

Rolf O Karlstrom

Some of the earliest axon pathways to form in the vertebrate forebrain are established as commissural and retinal axons cross t he midline of the diencephalon and telencephalon. To better understand axon guidance in the forebrain, we characterized the zebrafish belladonna ( bel ) mutation, which disrupts commissural and retinal axon guidance in the forebrain. Using a positional cloning strategy, we determined that the bel locus encodes zebrafish Lhx2, a lim-homeodomain transcription factor expressed in the brain, eye and fin buds. We show that bel(lhx2) function is required for patterning in the ventral forebrain and eye, and that loss of …

Detection Of Chlamydia In The Peripheral Blood Cells Of Normal Donors Using In Vitro Culture, Immunofluorescence Microscopy And Flow Cytometry Techniques, Frances Cirino, Wilmore Webley, Corrie West, Nancy L. Croteau, Chester Andrzejewski Jr., Elizabeth S. Stuart

Wilmore C Webley

BACKGROUND: Chlamydia trachomatis (Ct) and Chlamydia pneumoniae (Cp) are medically significant infectious agents associated with various chronic human pathologies. Nevertheless, specific roles in disease progression or initiation are incompletely defined. Both pathogens infect established cell lines in vitro and polymerase chain reaction (PCR) has detected Chlamydia DNA in various clinical specimens as well as in normal donor peripheral blood monocytes (PBMC). However, Chlamydia infection of other blood cell types, quantification of Chlamydia infected cells in peripheral blood and transmission of this infection in vitro have not been examined.

METHODS: Cp specific titers were assessed for sera from 459 normal human …

Two Putative C-Type Multiheme Cytochromes Required For The Expression Of Omcb, And Outer Membrane Protein Essential For Optimal Fe(Iii) Reduction In Geobacter Sulfurreducens, Byoung-Chan Kim, Xinlei Qian, Ching Leang, Maddalena V. Coppi, Derek Lovley

Derek Lovley

Deletion of two homologous Geobacter sulfurreducens c-type cytochrome genes, omcG and omcH, decreased the rate of Fe(III) reduction and decreased the level of an outer membrane cytochrome critical for Fe(III) reduction, OmcB, without affecting its transcription. Expression of either gene restored Fe(III) reduction and OmcB expression, suggesting functional similarity.

Dna Microarray And Proteomic Analyses Of The Rpos Regulon In Geobacter Sulfurreducens, Carol Giometti, Cinthia Núñez, Sandra Tollaksen, Abraham Esteve-Núñez, Tripti Khare, Winston Lin, Derek Lovley, Barbara Methѐ

Derek Lovley

The regulon of the sigma factor RpoS was defined in Geobacter sulfurreducens by using a combination of DNA microarray expression profiles and proteomics. An rpoS mutant was examined under steady-state conditions with acetate as an electron donor and fumarate as an electron acceptor and with additional transcriptional profiling using Fe(III) as an electron acceptor. Expression analysis revealed that RpoS acts as both a positive and negative regulator. Many of the RpoS-dependent genes determined play roles in energy metabolism, including the tricarboxylic acid cycle, signal transduction, transport, protein synthesis and degradation, and amino acid metabolism and transport. As expected, RpoS activated …

Motion Flow Estimation From Image Sequences With Applications To Biological Growth And Motility, Gang Dong, Tobias I. Baskin, Kannappan Palaniappan

Biology Department Faculty Publication Series

In this paper, a new method for motion flow estimation that considers errors in all the derivative measurements is presented. Based on the total least squares (TLS) model, we accurately estimate the motion flow in the general noise case by combining noise model (in form of covariance matrix) with a parametric motion model. The proposed algorithm is tested on two different types of biological motion, a growing plant root and a gastrulating embryo, with sequences obtained microscopically. The local, instantaneous velocity field estimated by the algorithm reveals the behavior of the underlying cellular elements.

Cortical Microtubule Arrays Lose Uniform Alignment Between Cells And Are Oryzalin Resistant In The Arabidopsis Mutant, Radially Swollen 6, A Bannigan, Amd Wiedemeier, Re Williamson, Rl Overall, Ti Baskin

Biology Department Faculty Publication Series

No abstract provided.

Suprachiasmatic Regulation Of Circadian Rhythms Of Gene Expression In Hamster Peripheral Organs: Effects Of Transplanting The Pacemaker, Hg Guo, Jm Brewer, Mn Lehman, El Bittman

Biology Department Faculty Publication Series

No abstract provided.

The Quick And The Fast: The Evolution Of Acceleration Capacity In Anolis Lizards, Bieke Vanhooydonck, Anthony Herrel, Raoul Van Damme, Duncan J. Irschick

Biology Department Faculty Publication Series

Although of prime ecological relevance, acceleration capacity is a poorly understood locomotor performance trait in terrestrial vertebrates. No empirical data exist on which design characteristics determine acceleration capacity among species and whether these design traits influence other aspects of locomotor performance. In this study we explore how acceleration capacity and sprint speed have evolved in Anolis lizards. We investigate whether the same or different morphological traits (i.e., limb dimensions and muscle mass) correlate with both locomotor traits. Within our sample of Anolis lizards, relative sprint speed and acceleration capacity coevolved. However, whereas the variation in relative acceleration capacity is primarily …

Belladonna/(Lhx2) Is Required For Neural Patterning And Midline Axon Guidance In The Zebrafish Forebrain, Anandita Seth, Jay Culverwell, Mitch Walkowicz, Sabrina Toro, Jens M. Rick, Stephan Neuhauss, Zoltan M. Varga, Rolf O. Karlstrom

Biology Department Faculty Publication Series

Some of the earliest axon pathways to form in the vertebrate forebrain are established as commissural and retinal axons cross the midline of the diencephalon and telencephalon. To better understand axon guidance in the forebrain, we characterized the zebrafish belladonna (bel) mutation, which disrupts commissural and retinal axon guidance in the forebrain. Using a positional cloning strategy we determined that the bel locus encodes zebrafish Lhx2, a lim-homeodomain transcription factor expressed in the brain, eye, and fin buds. We show that bel(lhx2) function is required for patterning in the ventral forebrain and eye and that loss of bel …

The Physiology Of Cranberry Yield, Teryl Roper

Cranberry Station Fact Sheets

No abstract provided.

2006 Chart Book: Nutrition Management For Producing Bogs, Carolyn J. Demoranville

Cranberry Chart Book - Management Guide

No abstract provided.

2006 Chart Book: Table Of Contents, University Of Massachusetts Amherst Cranberry Station

Cranberry Chart Book - Management Guide

No abstract provided.

2006 Chart Book: Groundwater Protection Regulations And Zone Ii, Martha M. Sylvia

Cranberry Chart Book - Management Guide

No abstract provided.

Research Update Meeting 2006 - Sare Project, Water And Plant Canopy Management: Sanding, Pruning, Irrigation, Drainage, Carolyn J. Demoranville, Hilary A. Sandler, Frank Caruso, Anne L. Averill, Justine Vanden Heuvel, Martha Sylvia

Cranberry Station Extension meetings

No abstract provided.