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Full-Text Articles in Life Sciences

Employing Ai To Enhance In-Class Role Playing Scenarios, Eric Fournier Apr 2024

Employing Ai To Enhance In-Class Role Playing Scenarios, Eric Fournier

Generative AI Teaching Activities

Role playing can deepen student’s engagement with course content and help them develop skills while learning course material. Students will use AI to develop their characters and help them craft compelling arguments in the role-play scenarios


Teaching Evolutionary Principles With Ai Image Generators, Jacqueline Garnett Apr 2024

Teaching Evolutionary Principles With Ai Image Generators, Jacqueline Garnett

Generative AI Teaching Activities

The purpose of this assignment is for students to practice constructing phylogenies using the principle of parsimony. In this activity, students will use an AI Image Generator to create a grid of images of the same organism and identify a series of traits that vary to build a possible phylogenetic tree.


Biology Department Publications: 2023, Sam Lindgren Feb 2024

Biology Department Publications: 2023, Sam Lindgren

Biology Department Bibliographies

This document is a non-comprehensive list of publications made by graduate students, post-doctoral researchers, and faculty members in the Biology Department in 2023. It indexes those publications available through PubMed and Scopus, and serves as an archival record of the Department’s robust scholarly contributions.


Charged Pore-Lining Residues Are Required For Normal Channel Kinetics In The Eukaryotic Mechanosensitive Ion Channel Msl1, Angela M. Schlegel, Elizabeth S. Haswell Dec 2020

Charged Pore-Lining Residues Are Required For Normal Channel Kinetics In The Eukaryotic Mechanosensitive Ion Channel Msl1, Angela M. Schlegel, Elizabeth S. Haswell

Biology Faculty Publications & Presentations

Mechanosensitive (MS) ion channels are widespread mechanisms for cellular mechanosensation that can be directly activated by increasing membrane tension. The well-studied MscS family of MS ion channels is found in bacteria, archaea, and plants. MscS-Like (MSL)1 is localized to the inner mitochondrial membrane of Arabidopsis thaliana, where it is required for normal mitochondrial responses to oxidative stress. Like Escherichia coli MscS, MSL1 has a pore-lining helix that is kinked. However, in MSL1 this kink is comprised of two charged pore-lining residues, R326 and D327. Using single-channel patch-clamp electrophysiology in E. coli, we show that altering the size and …


Single‐Molecule 3d Orientation Imaging Reveals Nanoscale Compositional Heterogeneity In Lipid Membranes, Jin Lu, Hesam Mazidi, Tianben Ding, Oumeng Zhang, Matthew D. Lew Sep 2020

Single‐Molecule 3d Orientation Imaging Reveals Nanoscale Compositional Heterogeneity In Lipid Membranes, Jin Lu, Hesam Mazidi, Tianben Ding, Oumeng Zhang, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

In soft matter, thermal energy causes molecules to continuously translate and rotate, even in crowded environments, thereby impacting the spatial organization and function of most molecular assemblies, such as lipid membranes. Directly measuring the orientation and spatial organization of large collections (>3000 molecules μm−2) of single molecules with nanoscale resolution remains elusive. In this paper, we utilize SMOLM, single‐molecule orientation localization microscopy, to directly measure the orientation spectra (3D orientation plus “wobble”) of lipophilic probes transiently bound to lipid membranes, revealing that Nile red's (NR) orientation spectra are extremely sensitive to membrane chemical composition. SMOLM images resolve …


Structural Mechanism For Gating Of A Eukaryoticmechanosensitive Channel Of Small Conductance, Zengqin Deng, Grigory Maksaev, Angela M. Schlegel, Jingying Zhang, Michael Rau, James A.J. Fitzpatrick, Elizabeth S. Haswell, Peng Yuan Jul 2020

Structural Mechanism For Gating Of A Eukaryoticmechanosensitive Channel Of Small Conductance, Zengqin Deng, Grigory Maksaev, Angela M. Schlegel, Jingying Zhang, Michael Rau, James A.J. Fitzpatrick, Elizabeth S. Haswell, Peng Yuan

Biology Faculty Publications & Presentations

Mechanosensitive ion channels transduce physical force into electrochemical signaling that underlies an array of fundamental physiological processes, including hearing, touch, proprioception, osmoregulation, and morphogenesis. The mechanosensitive channels of small conductance (MscS) constitute a remarkably diverse superfamily of channels critical for management of osmotic pressure. Here, we present cryo-electron microscopy structures of a MscS homolog from Arabidopsis thaliana, MSL1, presumably in both the closed and open states. The heptameric MSL1 channel contains an unusual bowl-shaped transmembrane region, which is reminiscent of the evolutionarily and architecturally unrelated mechanosensitive Piezo channels. Upon channel opening, the curved transmembrane domain of MSL1 flattens and expands. …


The Mechanosensitive Ion Channel Msl10 Potentiates Responses To Cell Swelling In Arabidopsis Seedlings, Debarati Basu, Elizabeth S. Haswell Jul 2020

The Mechanosensitive Ion Channel Msl10 Potentiates Responses To Cell Swelling In Arabidopsis Seedlings, Debarati Basu, Elizabeth S. Haswell

Biology Faculty Publications & Presentations

The ability to respond to unanticipated increases in volume is a fundamental property of cells, essential for cellular integrity in the face of osmotic challenges. Plants must manage cell swelling during flooding, rehydration, and pathogen invasion-but little is known about the mechanisms by which this occurs. It has been proposed that plant cells could sense and respond to cell swelling through the action of mechanosensitive ion channels. Here, we characterize a new assay to study the effects of cell swelling on Arabidopsis thaliana seedlings and to test the contributions of the mechanosensitive ion channel MscS-like10 (MSL10). The assay incorporates both …


Plant Biomechanics: No Pain, No Gain For Birch Tree Stems, A. M. Schlegel, E. S. Haswell Feb 2020

Plant Biomechanics: No Pain, No Gain For Birch Tree Stems, A. M. Schlegel, E. S. Haswell

Biology Faculty Publications & Presentations

Allometric relationships between organism size and shape are often described in developmental or evolutionary terms. A new study characterizes a collapsing birch tree mutant and provides a genetic entry point into the biomechanical control of tree allometry.


Onramp: A Galaxy-Based Platform For Collaborative Annotation Of Eukaryotic Genomes, Yating Liu, Luke Sargent, Wilson Leung, Sarah C.R. Elgin, Jeremy Goecks Nov 2019

Onramp: A Galaxy-Based Platform For Collaborative Annotation Of Eukaryotic Genomes, Yating Liu, Luke Sargent, Wilson Leung, Sarah C.R. Elgin, Jeremy Goecks

Biology Faculty Publications & Presentations

G-OnRamp provides a user-friendly, web-based platform for collaborative, end-to-end annotation of eukaryotic genomes using UCSC Assembly Hubs and JBrowse/Apollo genome browsers with evidence tracks derived from sequence alignments, ab initio gene predictors, RNA-Seq data and repeat finders. G-OnRamp can be used to visualize large genomics datasets and to perform collaborative genome annotation projects in both research and educational settings.


The Impact Of Genetic Background And Cell Lineage On The Level And Pattern Of Gene Expression In Position Effect Variegation, Sarah C.R. Elgin, Sh Wang Nov 2019

The Impact Of Genetic Background And Cell Lineage On The Level And Pattern Of Gene Expression In Position Effect Variegation, Sarah C.R. Elgin, Sh Wang

Biology Faculty Publications & Presentations

"Background: Chromatin-based transcriptional silencing is often described as a stochastic process, largely because of the mosaic expression observed in position effect variegation (PEV), where a euchromatic reporter gene is silenced in some cells as a consequence of juxtaposition with heterochromatin. High levels of variation in PEV phenotypes are commonly observed in reporter stocks. To ascertain whether background mutations are the major contributors to this variation, we asked how much of the variation is determined by genetic variants segregating in the population, examining both the level and pattern of expression using the fruit fly, Drosophila melanogaster, as the model.

Results: Using …


Genetic And Physical Interactions Between The Organellar Mechanosensitive Ion Channel Homologs Msl1, Msl2, And Msl3 Reveal A Role For Inter-Organellar Communication In Plant Development, Josephine S. Lee, Margaret E. Wilson, Ryan A. Richardson, Elizabeth S. Haswell Mar 2019

Genetic And Physical Interactions Between The Organellar Mechanosensitive Ion Channel Homologs Msl1, Msl2, And Msl3 Reveal A Role For Inter-Organellar Communication In Plant Development, Josephine S. Lee, Margaret E. Wilson, Ryan A. Richardson, Elizabeth S. Haswell

Biology Faculty Publications & Presentations

Plant development requires communication on many levels, including between cells and between organelles within a cell. For example, mitochondria and plastids have been proposed to be sensors of environmental stress and to coordinate their re- sponses. Here we present evidence for communication between mitochondria and chloroplasts during leaf and root development, based on genetic and physical inter- actions between three Mechanosensitive channel of Small conductance-Like (MSL) proteins from Arabidopsis thaliana. MSL proteins are Arabidopsis homologs of the bac- terial Mechanosensitive channel of Small conductance (MscS), which relieves cellular osmotic pressure to protect against lysis during hypoosmotic shock. MSL1 localizes to …


Long-Term, Super-Resolution Imaging Of Amyloid Structures Using Transient Amyloid Binding Microscopy, Tianben Ding, Kevin Spehar, Jan Bieschke, Matthew D. Lew Feb 2019

Long-Term, Super-Resolution Imaging Of Amyloid Structures Using Transient Amyloid Binding Microscopy, Tianben Ding, Kevin Spehar, Jan Bieschke, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Amyloid fibrils and tangles are signatures of Alzheimer disease, but nanometer-sized aggregation intermediates are hypothesized to be the structures most toxic to neurons. The structures of these oligomers are too small to be resolved by conventional light microscopy. We have developed a simple and versatile method, called transient amyloid binding (TAB), to image amyloid structures with nanoscale resolution using amyloidophilic dyes, such as Thioflavin T, without the need for covalent labeling or immunostaining of the amyloid protein. Transient binding of ThT molecules to amyloid structures over time generates photon bursts that are used to localize single fluorophores with nanometer precision. …


Anolis Newsletter Vii, James T. Stroud, Anthony J. Geneva, Jonathan B. Losos Jan 2019

Anolis Newsletter Vii, James T. Stroud, Anthony J. Geneva, Jonathan B. Losos

Biology Faculty Publications & Presentations

Newsletter for the 7th Anolis Symposium, Fairchild Tropical Botanic Gardens, Miami, Florida, 17-18 March 2018.

It had been nearly a decade since the previous Anolis symposium was held in Cambridge, MA, at the Museum for Comparative Zoology, Harvard. A reunion of anole biologists en masse was long past due and it was decided that this symposium would be slightly different – we were going to hold it somewhere with anoles! And so, on the weekend of 17-18th March, 2018, nearly 70 anole biologists traveled to sunny south Florida to attend the 7th Anolis Symposium held at the beautiful Fairchild Tropical …


Generating Genome Browsers To Facilitate Undergraduate-Driven Collaborative Genome Annotation, Luke Sargent, Yating Liu, Wilson Leung, Nathan Mortimer, David Lopatto, Jeremy Goecks, Sarah C.R. Elgin Jan 2019

Generating Genome Browsers To Facilitate Undergraduate-Driven Collaborative Genome Annotation, Luke Sargent, Yating Liu, Wilson Leung, Nathan Mortimer, David Lopatto, Jeremy Goecks, Sarah C.R. Elgin

Biology Faculty Publications & Presentations

Scientists are sequencing new genomes at an increasing rate with the goal of associating genome contents with phenotypic traits. After a new genome is sequenced and assembled, structural gene annotation is often the first step in analysis. Despite advances in computational gene prediction algorithms, most eukaryotic genomes still benefit from manual gene annotation. Undergraduates can become skilled annotators, and in the process learn both about genes/genomes and about how to utilize large datasets. Data visualizations provided by a genome browser are essential for manual gene annotation, enabling annotators to quickly evaluate multiple lines of evidence (e.g., sequence similarity, RNA-Seq, gene …


Elucidating A Role For The Cytoplasmic Domain In The Mycobacterium Tuberculosis Mechanosensitive Channel Of Large Conductance, Nadia Herrera, Grigory Maksaev, Elizabeth S. Haswell, Douglas Rees Oct 2018

Elucidating A Role For The Cytoplasmic Domain In The Mycobacterium Tuberculosis Mechanosensitive Channel Of Large Conductance, Nadia Herrera, Grigory Maksaev, Elizabeth S. Haswell, Douglas Rees

Biology Faculty Publications & Presentations

Microbial survival in dynamic environments requires the ability to successfully respond to abrupt changes in osmolarity. The mechanosensitive channel of large conductance (MscL) is a ubiquitous channel that facilitates the survival of bacteria and archaea under severe osmotic downshock conditions by relieving excess turgor pressure in response to increased membrane tension. A prominent structural feature of MscL, the cytoplasmic C-terminal domain, has been suggested to infuence channel assembly and function. In this report, we describe the X-ray crystal structure and electrophysiological properties of a C-terminal domain truncation of the Mycobacterium tuberculosis MscL (MtMscLΔC). A crystal structure of MtMscLΔC solubilized in …


Nonpolar Residues In The Presumptive Pore‐Lining Helix Of Mechanosensitive Channel Msl10 Influence Channel Behavior And Establish A Nonconducting Function, Grigory Maksaev, Jennette K. Shoots, Simran Ohri, Elizabeth S. Haswell Jun 2018

Nonpolar Residues In The Presumptive Pore‐Lining Helix Of Mechanosensitive Channel Msl10 Influence Channel Behavior And Establish A Nonconducting Function, Grigory Maksaev, Jennette K. Shoots, Simran Ohri, Elizabeth S. Haswell

Biology Faculty Publications & Presentations

Mechanosensitive (MS) ion channels provide a universal mechanism for sensing and responding to increased membrane tension. MscS‐like (MSL) 10 is a relatively well‐studied MS ion channel from Arabidopsis thaliana that is implicated in cell death signaling. The relationship between the amino acid sequence of MSL10 and its conductance, gating tension, and opening and closing kinetics remains unstudied. Here, we identify several nonpolar residues in the presumptive pore‐lining transmembrane helix of MSL10 (TM6) that contribute to these basic channel properties. F553 and I554 are essential for wild type channel conductance and the stability of the open state. G556, a glycine residue …


Integrating Species Traits Into Species Pools, Marko J. Spasojevic, Christopher P. Catano, Joseph A. Lamanna Jun 2018

Integrating Species Traits Into Species Pools, Marko J. Spasojevic, Christopher P. Catano, Joseph A. Lamanna

Biology Faculty Publications & Presentations

Despite decades of research on the species‐pool concept and the recent explosion of interest in trait‐based frameworks in ecology and biogeography, surprisingly little is known about how spatial and temporal changes in species‐pool functional diversity (SPFD) influence biodiversity and the processes underlying community assembly. Current trait‐based frameworks focus primarily on community assembly from a static regional species pool, without considering how spatial or temporal variation in SPFD alters the relative importance of deterministic and stochastic assembly processes. Likewise, species‐pool concepts primarily focus on how the number of species in the species pool influences local biodiversity. However, species pools with similar …


Bioinformatics Core Competencies For Undergraduate Life Sciences Education, Sarah C.R. Elgin, Melissa Wilson - Sayers, Charles Hauser, Michael Sierk, Srebrenka Robic, Anne Rosenwald, Todd Smith, Eric W. Triplett, Jason Williams, Elizabeth Dinsdale, William Morgan, James Burnette, Samuel Donovan, Jennifer Drew, Edison Fowlks, Sebastian Galindo-Gonzales, Anya Goodman, Nealy Grandgenett, Carlos Goller, John Jungck, Jeffrey Newman, William Pearson, Elizabeth Ryder, Rafael Tosado-Acevedo, William Tapprich, Tammy Tobin, Arlin Toro-Martínez, Lonnie Welch, Robin Wright, Lindsay Barone, David Ebenbach, Mindy Mcwilliams, Kimberly Olney, Mark A. Pauley Jun 2018

Bioinformatics Core Competencies For Undergraduate Life Sciences Education, Sarah C.R. Elgin, Melissa Wilson - Sayers, Charles Hauser, Michael Sierk, Srebrenka Robic, Anne Rosenwald, Todd Smith, Eric W. Triplett, Jason Williams, Elizabeth Dinsdale, William Morgan, James Burnette, Samuel Donovan, Jennifer Drew, Edison Fowlks, Sebastian Galindo-Gonzales, Anya Goodman, Nealy Grandgenett, Carlos Goller, John Jungck, Jeffrey Newman, William Pearson, Elizabeth Ryder, Rafael Tosado-Acevedo, William Tapprich, Tammy Tobin, Arlin Toro-Martínez, Lonnie Welch, Robin Wright, Lindsay Barone, David Ebenbach, Mindy Mcwilliams, Kimberly Olney, Mark A. Pauley

Biology Faculty Publications & Presentations

Although bioinformatics is becoming increasingly central to research in the life sciences, bioinformatics skills and knowledge are not well integrated into undergraduate biology education. This curricular gap prevents biology students from harnessing the full potential of their education, limiting their career opportunities and slowing research innovation. To advance the integration of bioinformatics into life sciences education, a framework of core bioinformatics competencies is needed. To that end, we here report the results of a survey of biology faculty in the United States about teaching bioinformatics to undergraduate life scientists. Responses were received from 1,260 faculty representing institutions in all fifty …


Predator-By-Environment Interactions Mediate Bacterial Competition In The Dictyostelium Discoideum Microbiome, R Fredrik Inglis, Odion Asikhia, Erica Ryu, David C. Queller, Joan E. Strassmann Apr 2018

Predator-By-Environment Interactions Mediate Bacterial Competition In The Dictyostelium Discoideum Microbiome, R Fredrik Inglis, Odion Asikhia, Erica Ryu, David C. Queller, Joan E. Strassmann

Biology Faculty Publications & Presentations

Interactions between species and their environment play a key role in the evolution of diverse communities, and numerous studies have emphasized that interactions among microbes and among trophic levels play an important role in maintaining microbial diversity and ecosystem functioning. In this study, we investigate how two of these types of interactions, public goods cooperation through the production of iron scavenging siderophores and predation by the social amoeba Dictyostelium discoideum, mediate competition between two strains of Pseudomonas fluorescens that were co-isolated from D. discoideum. We find that although we are able to generally predict the competitive outcomes between …


An Insoluble Iron Complex Coated Cathode Enhances Direct Electron Uptake By Rhodopseudomonas Palustris Tie-1, Karthikeyan Rengasamy, Tahina Ranaivoarisoa, Rajesh Singh, Arpita Bose Apr 2018

An Insoluble Iron Complex Coated Cathode Enhances Direct Electron Uptake By Rhodopseudomonas Palustris Tie-1, Karthikeyan Rengasamy, Tahina Ranaivoarisoa, Rajesh Singh, Arpita Bose

Biology Faculty Publications & Presentations

Microbial electrosynthesis (MES) is a promising bioelectrochemical approach to produce biochemicals. A previous study showed that Rhodopseudomonas palustris TIE-1 can directly use poised electrodes as electron donors for photoautotrophic growth at cathodic potentials that avoid electrolytic H2 production (photoelectroautotrophy). To make TIE-1 an effective biocatalyst for MES, we need to improve its electron uptake ability and growth under photoelectroautotrophic conditions. Because TIE-1 interacts with various forms of iron while using it as a source of electrons for photoautotrophy (photoferroautotrophy), we tested the ability of iron-based redox mediators to enhance direct electron uptake. Our data show that soluble iron cannot …


Kelch F-Box Protein Positively Influences Arabidopsis Seed Germination By Targeting Phytochrome-Interacting Factor1, Manoj Majee, Santosh Kumar, Praveen Kumar Kathare, Shuiqin Wu, Derek Gingerich, Nihar R. Nayak, Louai Salaita, Randy Dinkins, Kathleen Martin, Michael Goodin, Lynnette M A Dirk, Taylor D. Lloyd, Ling Zhu, Joseph Chappell, Arthur G. Hunt, Richard D. Vierstra, Enamul Huq, A Bruce Downie Apr 2018

Kelch F-Box Protein Positively Influences Arabidopsis Seed Germination By Targeting Phytochrome-Interacting Factor1, Manoj Majee, Santosh Kumar, Praveen Kumar Kathare, Shuiqin Wu, Derek Gingerich, Nihar R. Nayak, Louai Salaita, Randy Dinkins, Kathleen Martin, Michael Goodin, Lynnette M A Dirk, Taylor D. Lloyd, Ling Zhu, Joseph Chappell, Arthur G. Hunt, Richard D. Vierstra, Enamul Huq, A Bruce Downie

Biology Faculty Publications & Presentations

Seeds employ sensory systems that assess various environmental cues over time to maximize the successful transition from embryo to seedling. Here we show that the Arabidopsis F-BOX protein COLD TEMPERATURE-GERMINATING (CTG)-10, identified by activation tagging, is a positive regulator of this process. When overexpressed (OE), CTG10 hastens aspects of seed germination. CTG10 is expressed predominantly in the hypocotyl, and the protein is localized to the nucleus. CTG10 interacts with PHYTOCHROME-INTERACTING FACTOR 1 (PIF1) and helps regulate its abundance in planta. CTG10-OE accelerates the loss of PIF1 in light, increasing germination efficiency, while PIF1-OE lines fail to complete germination in …


Proteasome Storage Granules Protect Proteasomes From Autophagic Degradation Upon Carbon Starvation, Richard S. Marshall, Richard D. Vierstra Apr 2018

Proteasome Storage Granules Protect Proteasomes From Autophagic Degradation Upon Carbon Starvation, Richard S. Marshall, Richard D. Vierstra

Biology Faculty Publications & Presentations

26S proteasome abundance is tightly regulated at multiple levels, including the elimination of excess or inactive particles by autophagy. In yeast, this proteaphagy occurs upon nitrogen starvation but not carbon starvation, which instead stimulates the rapid sequestration of proteasomes into cytoplasmic puncta termed proteasome storage granules (PSGs). Here, we show that PSGs help protect proteasomes from autophagic degradation. Both the core protease and regulatory particle sub-complexes are sequestered separately into PSGs via pathways dependent on the accessory proteins Blm10 and Spg5, respectively. Modulating PSG formation, either by perturbing cellular energy status or pH, or by genetically eliminating factors required for …


The Life Of A Microtubule, Ram Dixit, Sabine Petry Mar 2018

The Life Of A Microtubule, Ram Dixit, Sabine Petry

Biology Faculty Publications & Presentations

The Minisymposium “The Life of a Microtubule: Birth, Dynamics and Function” highlighted new findings on how microtubules (MTs) are made, how their length and spatial organization is regulated, and finally how they contribute to cellular functions.


Overdispersed Spatial Patterning Of Dominant Bunchgrasses In Southeastern Pine Savannas, Katherines A. Hovanes, Kyle E. Harms, Paul R. Gagnon, Jonathan A. Myers, Bret D. Elderd Feb 2018

Overdispersed Spatial Patterning Of Dominant Bunchgrasses In Southeastern Pine Savannas, Katherines A. Hovanes, Kyle E. Harms, Paul R. Gagnon, Jonathan A. Myers, Bret D. Elderd

Biology Faculty Publications & Presentations

Spatial patterning is a key natural history attribute of sessile organisms that frequently emerges from and dictates potential for interactions among organisms. We tested whether bunchgrasses, the dominant plant functional group in longleaf pine savanna groundcover communities, are nonrandomly patterned by characterizing the spatial dispersion of three bunchgrass species across six sites in Louisiana and Florida. We mapped bunchgrass tussocks of >5.0 cm basal diameter in three [Formula: see text] plots at each site. We modeled tussocks as two-dimensional objects to analyze their spatial relationships while preserving sizes and shapes of individual tussocks. Tussocks were overdispersed (more regularly spaced than …


New Classification Of The Dictyostelids, Sanea Sheikh, Mats Thulin, James C. Cavender, Ricardo Escalante, Shin-Ichi Kawakami, Carlos Lado, John C. Landolt, Vidyanand Nanjundiah, David C. Queller, Joan E. Strassmann, Frederick W. Spiegel, Steven L. Stephenson, Eduardo M. Vadell, Sandra L. Baldauf Feb 2018

New Classification Of The Dictyostelids, Sanea Sheikh, Mats Thulin, James C. Cavender, Ricardo Escalante, Shin-Ichi Kawakami, Carlos Lado, John C. Landolt, Vidyanand Nanjundiah, David C. Queller, Joan E. Strassmann, Frederick W. Spiegel, Steven L. Stephenson, Eduardo M. Vadell, Sandra L. Baldauf

Biology Faculty Publications & Presentations

Traditional morphology-based taxonomy of dictyostelids is rejected by molecular phylogeny. A new classification is presented based on monophyletic entities with consistent and strong molecular phylogenetic support and that are, as far as possible, morphologically recognizable. All newly named clades are diagnosed with small subunit ribosomal RNA (18S rRNA) sequence signatures plus morphological synapomorphies where possible. The two major molecular clades are given the rank of order, as Acytosteliales ord. nov. and Dictyosteliales. The two major clades within each of these orders are recognized and given the rank of family as, respectively, Acytosteliaceae and Cavenderiaceae fam. nov. in Acytosteliales, and Dictyosteliaceae …


Elucidating A Role For The Cytoplasmic Domain In The Mycobacterium Tuberculosis Mechanosensitive Channel Of Large Conductance, Nadia Herrera, Grigory Maksaev, Elizabeth S. Haswell, Douglas C. Rees Jan 2018

Elucidating A Role For The Cytoplasmic Domain In The Mycobacterium Tuberculosis Mechanosensitive Channel Of Large Conductance, Nadia Herrera, Grigory Maksaev, Elizabeth S. Haswell, Douglas C. Rees

All Faculty Publications

Microbial survival in dynamic environments requires the ability to successfully respond to abrupt changes in osmolarity. The mechanosensitive channel of large conductance (MscL) is a ubiquitous channel that facilitates the survival of bacteria and archaea under severe osmotic downshock conditions by relieving excess turgor pressure in response to increased membrane tension. A prominent structural feature of MscL, the cytoplasmic C-terminal domain, has been suggested to infuence channel assembly and function. In this report, we describe the X-ray crystal structure and electrophysiological properties of a C-terminal domain truncation of the Mycobacterium tuberculosis MscL (MtMscLΔC). A crystal structure of MtMscLΔC solubilized in …


Draft Genome Sequence Of Streptomyces Sp. Strain Jv178, A Producer Of Clifednamide-Type Polycyclic Tetramate Macrolactams, Yunci Qi, John M. D’Alessandro, Joshua A.V Blodgett Jan 2018

Draft Genome Sequence Of Streptomyces Sp. Strain Jv178, A Producer Of Clifednamide-Type Polycyclic Tetramate Macrolactams, Yunci Qi, John M. D’Alessandro, Joshua A.V Blodgett

Biology Faculty Publications & Presentations

Here, we report the draft genome sequence of Streptomyces sp. JV178, a strain originating from Connecticut (USA) garden soil. This strain produces the polycyclic tetramate macrolactam compounds clifednamides A and B. The draft genome contains 10.65 Mb, 9,045 predicted protein coding sequences, and several natural product biosynthetic loci.


Phyllotactic Regularity Requires The Paf1 Complex In Arabidopsis, Kateryna Fal, Mengying Liu, Assem Duisembekova, Yassin Refahi, Elizabeth S. Haswell, Olivier Hamant Nov 2017

Phyllotactic Regularity Requires The Paf1 Complex In Arabidopsis, Kateryna Fal, Mengying Liu, Assem Duisembekova, Yassin Refahi, Elizabeth S. Haswell, Olivier Hamant

Biology Faculty Publications & Presentations

In plants, aerial organs are initiated at stereotyped intervals, both spatially (every 137° in a pattern called phyllotaxis) and temporally (at prescribed time intervals called plastochrons). To investigate the molecular basis of such regularity, mutants with altered architecture have been isolated. However, most of them only exhibit plastochron defects and/or produce a new, albeit equally reproducible, phyllotactic pattern. This leaves open the question of a molecular control of phyllotaxis regularity. Here, we show that phyllotaxis regularity depends on the function of VIP proteins, components of the RNA polymerase II-associated factor 1 complex (Paf1c). Divergence angles between successive organs along the …


Anaerobic Oxidation Of Ethane, Propane, And Butane By Marine Microbes: A Mini Review, Rajesh Singh, Michael S. Guzman, Arpita Bose Oct 2017

Anaerobic Oxidation Of Ethane, Propane, And Butane By Marine Microbes: A Mini Review, Rajesh Singh, Michael S. Guzman, Arpita Bose

Biology Faculty Publications & Presentations

The deep ocean and its sediments are a continuous source of non-methane short-chain alkanes (SCAs) including ethane, propane, and butane. Their high global warming potential, and contribution to local carbon and sulfur budgets has drawn significant scientific attention. Importantly, microbes can use gaseous alkanes and oxidize them to CO2, thus acting as effective biofilters. A relative decrease of these gases with a concomitant 13C enrichment of propane and n-butane in interstitial waters vs. the source suggests microbial anaerobic oxidation. The reported uncoupling of sulfate-reduction (SR) from anaerobic methane oxidation supports their microbial consumption. To date, strain …


Photosensing And Thermosensing By Phytochrome B Require Both Proximal And Distal Allosteric Features Within The Dimeric Photoreceptor, E Sethe Burgie, Adam N. Bussell, Shu-Hui Lye, Tong Wang, Weiming Hu, Katrice E. Mcloughlin, Erin L. Weber, Huilin Li, Richard D. Vierstra Oct 2017

Photosensing And Thermosensing By Phytochrome B Require Both Proximal And Distal Allosteric Features Within The Dimeric Photoreceptor, E Sethe Burgie, Adam N. Bussell, Shu-Hui Lye, Tong Wang, Weiming Hu, Katrice E. Mcloughlin, Erin L. Weber, Huilin Li, Richard D. Vierstra

Biology Faculty Publications & Presentations

Phytochromes (Phys) encompass a diverse collection of bilin-containing photoreceptors that help plants and microorganisms perceive light through photointerconversion between red light (Pr) and far-red light (Pfr)-absorbing states. In addition, Pfr reverts thermally back to Pr via a highly enthalpic process that enables temperature sensation in plants and possibly other organisms. Through domain analysis of the Arabidopsis PhyB isoform assembled recombinantly, coupled with measurements of solution size, photoconversion, and thermal reversion, we identified both proximal and distal features that influence all three metrics. Included are the downstream C-terminal histidine kinase-related domain known to promote dimerization and a conserved patch just upstream …