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- Amino acid sequence; Bacteria; Genetic code; Proteins -- Analysis; Proteolytic enzymes (1)
- Bacillus megaterium; Bacillus subtilis — Genetics; Bacterial spores; Genetic regulation; Germination (1)
- Bacillus subtilis; Drug resistance in microorganisms; Genetic transcription; Mutagenesis (1)
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- Genetic code; Genetic transcription; Shigella flexneri (1)
Articles 1 - 6 of 6
Full-Text Articles in Microbiology
Evaluating Snow Microbial Assemblages, Jenny Lam, Jessica K. Guy, Ryan Brock, Matt Oates, Alison E. Murray
Evaluating Snow Microbial Assemblages, Jenny Lam, Jessica K. Guy, Ryan Brock, Matt Oates, Alison E. Murray
Undergraduate Research Opportunities Program (UROP)
Psychrophiles are organisms that grow optimally below 20C (1). The US Great Basin is home to many mountain peaks with an abundance of alpine snow environments perfect for psychrophilic habitation. We analyzed samples from three different locations, Wheeler Peak, Pacific Crest Trail, and Mount Conness, characterizing and comparing the psychrophilic communities at varying depth intervals in the snow. Polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) showed no notable difference in community structure with depth, but there was a distinct difference when comparing different snow environments (i.e. shaded vs. full sun exposure). The chlorophyll concentration decreased as the …
Evaluation Of Virb Binding Site Contribution To The Regulation Of The Icsp Promoter In Shigella Flexneri, Juan C. Duhart, Maria I. Castellanos, Helen J. Wing
Evaluation Of Virb Binding Site Contribution To The Regulation Of The Icsp Promoter In Shigella Flexneri, Juan C. Duhart, Maria I. Castellanos, Helen J. Wing
Undergraduate Research Opportunities Program (UROP)
Shigella species are gram-negative, rod-shaped bacteria that are closely related to Escherichia coli. Virulent Shigella spp. are intracellular pathogens that invade, replicate and spread through epithelial cells of the lower intestine and cause bacillary dysentery in humans. This disease is characterized by a robust inflammatory response that results in fever, abdominal pain, and bloody diarrhea (3). According to the CDC, approximately 14,000 cases are reported each year in the United States alone. This number however, does not reflect the actual incidence of this disease as many cases go unreported. The molecular pathogenesis of these bacteria lies in the large virulence …
Modifying The Amino Acid Sequence In The Surface-Exposed Loops Of The Omptin Family Of Proteins To Determine Their Effect On Function, Natiera Magnuson, Eun-Hae Kim, Christian Ross, Helen J. Wing
Modifying The Amino Acid Sequence In The Surface-Exposed Loops Of The Omptin Family Of Proteins To Determine Their Effect On Function, Natiera Magnuson, Eun-Hae Kim, Christian Ross, Helen J. Wing
Undergraduate Research Opportunities Program (UROP)
The omptin family of proteins consists of proteases which lie in the outer membrane of some gram-negative, pathogenic bacteria such as Escherichia coli (OmpT), Shigella flexneri (IcsP), Salmonella typhimurium (PgtE), and Yersinia pestis (Pla). These proteases are highly conserved, sharing approximately 50% sequence identity and a β-barrel shape (fig. 1D). The differences in the structure of these four proteins are in the surface-exposed loop region surrounding the active site, but not in the active site itself [4]. These proteases are important for the virulence of many bacteria. For example, OmpT of E. coli cleaves an antimicrobial peptide secreted by epithelial …
Antibiotic Resistance In Bacillus Subtilis As Affected By Transcriptional Derepression And The Stringent Response, Brandon Eisinger, Ronald E. Yasbin, Eduardo A. Robleto
Antibiotic Resistance In Bacillus Subtilis As Affected By Transcriptional Derepression And The Stringent Response, Brandon Eisinger, Ronald E. Yasbin, Eduardo A. Robleto
Undergraduate Research Opportunities Program (UROP)
Bacterial cells under conditions of starvation or prolonged non-lethal selective pressures accumulate mutations in highly transcribed genes. This process is part of cellular programs to increase genetic diversity in conditions of stress, also known as stationary phase or stress-induced mutagenesis. This experiment investigated mutation frequencies for antibiotic resistance as affected by the stringent response. The stringent response is a global cellular process that initiates at the cessation of growth and mediates changes in gene expression that repress synthesis of ribosome components. We used Bacillus subtilis strains that differ in RelA proficiency. The relA gene controls the synthesis of (p)ppGpp, the …
The Small Regulatory Rna Ryhb Regulates Icsa Expression In Shigella Flexneri, Nick Egan, Helen J. Wing
The Small Regulatory Rna Ryhb Regulates Icsa Expression In Shigella Flexneri, Nick Egan, Helen J. Wing
Undergraduate Research Opportunities Program (UROP)
Shigella flexneri is a gram negative non-motile, non-spore forming, rod-shaped bacterium responsible for bacillary dysentery in humans. The master regulator, VirF, initiates a cascade of virulence gene activation by acting as a transcription factor for the gene encoding the global regulator, VirB (1). Production of VirB is also negatively regulated by the regulatory small RNA (sRNA), RyhB 2). Regulatory sRNAs are untranslated RNA molecules involved in the regulation of both transcription and translation. RyhB, a 90 nt sRNA, was first identified in E. coli and subsequently found in all Shigella species. In Shigella this sRNA is maximally expressed in response …
Examination Of Germination Receptors Of B. Subtilis And B. Megaterium, Shruti Patel, Alessio Luinetti, Ernesto Abel-Santos, Eduardo Robleto
Examination Of Germination Receptors Of B. Subtilis And B. Megaterium, Shruti Patel, Alessio Luinetti, Ernesto Abel-Santos, Eduardo Robleto
Undergraduate Research Opportunities Program (UROP)
Many bacterial species including those in the Bacilli group form spores as a mechanism to survive harsh conditions such as extreme temperature, radiation, chemicals, and nutrient starvation. By forming spores, they can remain metabolically dormant for an extended period and revert to their vegetative form when environment becomes favorable. This resumption of metabolism and growth is marked by a process called germination that is triggered by exogenous nutrients such as amino acids, sugars, and nucleotides. The (Ger) germination receptors that are postulated to respond to these germinants, in the case of B. subtilis and B. megaterium, are a complex of …