Showing 1591 - 1600 of 5709 Items

Alongside Despair: Signs of Life on the River des Peres

Date: 2020-01-01

Creator: Marina Henke

Access: Open access

This River des Peres is a partially enclosed river which runs through St. Louis, Missouri. Used since prior to the city’s founding, the des Peres has gone through two considerable engineering projects: one in 1901 in light of the World’s Fair, and one in 1923, which encapsulated more than half of the river and placed nearly five miles of it underground. Presently, the des Peres constitutes the backbone of the sanitary and sewer system of St. Louis city and county. Ultimately, the river offers a broad meditation on what it means to live around and in a “natural” waterway that is simultaneously not natural at all. Themes of St. Louis are equally reflected in the river: of environmental racism, of Midwestern decline, and of urban decay and renewal. Additionally, those who interact with the river prove a broad cast of characters. Through using a selection of interviews with locals, alongside an engagement with the work of contemporary poet Donald Finkel, this piece of creative nonfiction explores the multiplicity, and ultimately the value, of distorted natural spaces.


Polar oceanography: Engendering students with a sense of place and a sense of time

Date: 2016-06-01

Creator: Collin S. Roesler

Access: Open access



Metabolic Glycan Labeling-Based Screen to Identify Bacterial Glycosylation Genes

Date: 2020-12-11

Creator: Karen D. Moulton, Adedunmola P. Adewale, Hallie A. Carol, Sage A. Mikami, Danielle H., Dube

Access: Open access

Bacterial cell surface glycans are quintessential drug targets due to their critical role in colonization of the host, pathogen survival, and immune evasion. The dense cell envelope glycocalyx contains distinctive monosaccharides that are stitched together into higher order glycans to yield exclusively bacterial structures that are critical for strain fitness and pathogenesis. However, the systematic study and inhibition of bacterial glycosylation enzymes remains challenging. Bacteria produce glycans containing rare sugars refractory to traditional glycan analysis, complicating the study of bacterial glycans and the identification of their biosynthesis machinery. To ease the study of bacterial glycans in the absence of detailed structural information, we used metabolic glycan labeling to detect changes in glycan biosynthesis. Here, we screened wild-type versus mutant strains of the gastric pathogen Helicobacter pylori, ultimately permitting the identification of genes involved in glycoprotein and lipopolysaccharide biosynthesis. Our findings provide the first evidence that H. pylori protein glycosylation proceeds via a lipid carrier-mediated pathway that overlaps with lipopolysaccharide biosynthesis. Protein glycosylation mutants displayed fitness defects consistent with those induced by small molecule glycosylation inhibitors. Broadly, our results suggest a facile approach to screen for bacterial glycosylation genes and gain insight into their biosynthesis and functional importance, even in the absence of glycan structural information.


Genetic interactions of yeast eukaryotic translation initiation factor 5a (eIF5A) reveal connections to poly(A)-binding protein and protein kinase C signaling

Date: 2002-03-14

Creator: Sandro R. Valentini, Jason M. Casolari, Carla C. Oliveira, Pamela A. Silver, Anne E., McBride

Access: Open access

The highly conserved eukaryotic translation initiation factor eIF5A has been proposed to have various roles in the cell, from translation to mRNA decay to nuclear protein export. To further our understanding of this essential protein, three temperature-sensitive alleles of the yeast TIF51A gene have been characterized. Two mutant eIF5A proteins contain mutations in a proline residue at the junction between the two eIFSA domains and the third, strongest allele encodes a protein with a single mutation in each domain, both of which are required for the growth defect. The stronger tif51A alleles cause defects in degradation of short-lived mRNAs, supporting a role for this protein in mRNA decay. A multicopy suppressor screen revealed six genes, the overexpression of which allows growth of a tif51A-1 strain at high temperature; these genes include PAB1, PKC1, and PKC1 regulators WSC1, WSC2, and WSC3. Further results suggest that eIFSA may also be involved in ribosomal synthesis and the WSC/PKC1 signaling pathway for cell wall integrity or related processes.


Arginine methyltransferase affects interactions and recruitment of mRNA processing and export factors

Date: 2004-08-15

Creator: Michael C. Yu, François Bachand, Anne E. McBride, Suzanne Komili, Jason M., Casolari, Pamela A. Silver

Access: Open access

Hmt1 is the major type I arginine methyltransferase in the yeast Saccharomyces cerevisiae and facilitates the nucleocytoplasmic transport of mRNA-binding proteins through their methylation. Here we demonstrate that Hmt1 is recruited during the beginning of the transcriptional elongation process. Hmt1 methylates Yra1 and Hrp1, two mRNA-binding proteins important for mRNA processing and export. Moreover, loss of Hmt1 affects interactions between mRNA-binding proteins and Tho2, a component of the TREX (transcription/export) complex that is important for transcriptional elongation and recruitment of mRNA export factors. Furthermore, RNA in situ hybridization analysis demonstrates that loss of Hmt1 results in slowed release of HSP104 mRNA from the sites of transcription. Genome-wide location analysis shows that Hmt1 is bound to specific functional gene classes, many of which are also bound by Tho2 and other mRNA-processing factors. These data suggest a model whereby Hmt1 affects transcriptional elongation and, as a result, influences recruitment of RNA-processing factors.


From the editor

Date: 2014-01-01

Creator: Stephen Meardon

Access: Open access




Descriptive Catalogue of the Bowdoin College Art Collections

Date: 1895-01-01

Creator: Henry Johnson

Access: Open access

Includes index.


Four Artists

Date: 1982-01-01

Access: Open access

Bowdoin College Museum of Art exhibition catalogue from January 22-March 7, 1982.


Sri Lanka in 2018: Seeking a way forward

Date: 2019-02-01

Creator: Sree Padma

Access: Open access

The highlight of Maithripala Sirisena's presidency came in its very beginning when he ended a decade of autocracy by restoring democracy. And when rivalry with his own prime minister, Ranil Wickremesinghe, devolved into a constitutional crisis, Sirisena was forced to abide by the democratic norms he had restored.