Publications by authors named "Amanda L Miller"

strain B59671 naturally produces thermophilin 110, a broad-spectrum bacteriocin encoded within the bacteriocin-like peptide () gene cluster, and thermophilin 13 from a separate chromosomal locus. Analysis of the gene cluster revealed two genes, and , as potentially encoding bacteriocins. Deletion of from the B59671 chromosome did not result in a loss of antimicrobial activity against either ST113 or F.

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Bacteriocin production in is regulated by cell density-dependent signaling molecules, including BlpC, which regulates transcription from within the bacteriocin-like peptide () gene cluster. In some strains, such as ST106, this signaling system does not function properly, and BlpC must be supplied exogenously to induce bacteriocin production. In other strains, such as B59671, bacteriocin (thermophilin 110 in strain B59671) production occurs naturally.

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Ice cream manufacture commonly results in the accumulation of wasted product that contains valuable food-grade quality components, including fat, carbohydrates, and protein. Methods have been developed for recovering the fat from this waste stream, but this results in the generation of a co-product rich in fermentable carbohydrates. This study aimed to investigate the potential for using this co-product as a fermentation substrate for production of antimicrobial peptides, called bacteriocins, by dairy starter cultures.

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Objective: Thermophilin 110, a bacteriocin produced by Streptococcus thermophilus B59671, inhibited planktonic growth and biofilm formation of Cutibacterium acnes, a commensal skin bacterium associated with the inflammatory disease, acne vulgaris, and more invasive deep tissue infections.

Results: Thermophilin 110 prevented planktonic growth of C. acnes at a concentration ≥ 160 AU mL; while concentrations ≥ 640 AU mL resulted in a > 5 log reduction in viable planktonic cell counts and inhibited biofilm formation.

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Consumers' growing interest in fermented dairy foods necessitates research on a wide array of lactic acid bacterial strains to be explored and used. This study aimed to investigate the differences in the proteolytic capacity of Lactobacillus helveticus strains B1929 and ATCC 15009 on the fermentation of commercial ultra-pasteurized (UHT) skim milk and reconstituted nonfat dried milk powder (at a comparable protein concentration, 4%). The antihypertensive properties of the fermented milk, measured by angiotensin-I-converting enzyme inhibitory (ACE-I) activity, were compared.

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is a genus of bacteria emerging as new biocontrol agents in agriculture. Although iron acquisition is essential for the bacteria, no siderophore has been identified from any . Here, we report the identification of the first siderophore, 1,8-bis(2,3-dihydroxybenzoyl)spermidine (lysochelin), and its biosynthetic gene cluster from .

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Background: Few large investigations have addressed the prevalence of COVID-19 infection among trauma patients and impact on providers. The purpose of this study was to quantify the prevalence of COVID-19 infection among trauma patients by timing of diagnosis, assess nosocomial exposure risk, and evaluate the impact of COVID-19 positive status on morbidity and mortality.

Methods: Registry data from adults admitted 4/1/2020-10/31/2020 from 46 level I/II trauma centers were grouped by: timing of first positive status (Day 1, Day 2-6, or Day ≥ 7); overall Positive/Negative status; or Unknown if test results were unavailable.

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Deposition of human amyloids is associated with complex human diseases such as Alzheimer's and Parkinson's. Amyloid proteins are also produced by bacteria. The bacterial amyloid curli, found in the extracellular matrix of both commensal and pathogenic enteric bacterial biofilms, forms complexes with extracellular DNA, and recognition of these complexes by the host immune system may initiate an autoimmune response.

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Bacteria are microscopic, single-celled organisms known for their ability to adapt to their environment. In response to stressful environmental conditions or in the presence of a contact surface, they commonly form multicellular aggregates called biofilms. Biofilms form on various abiotic or biotic surfaces through a dynamic stepwise process involving adhesion, growth, and extracellular matrix production.

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Curli, a major component of the bacterial biofilms in the intestinal tract, activates pattern recognition receptors and triggers joint inflammation after infection with Salmonella enterica serovar Typhimurium. The factors that allow Typhimurium to disperse from biofilms and invade the epithelium to establish a successful infection during acute inflammation remain unknown. Here, we studied Typhimurium biofilms and to understand how the inflammatory environment regulates the switch between multicellular and motile Typhimurium in the gut.

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Adults with disabilities have long been at the forefront of disability advocacy in the United States. Grounded in the tenets of radical disability studies and principles of disability justice, this study explored the lived experiences of 12 adults with disabilities, including intellectual disability and developmental disabilities, with a particular focus on self-advocacy. Two focus groups were primary data sources.

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Covering: up to August 2021 is a genus of Gram-negative bacteria that was classified in 1987. Several species are emerging as new biocontrol agents for crop protection in agriculture. are prolific producers of new bioactive natural products that are largely underexplored.

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The human microbiota is the community of microorganisms that live upon or within their human host. The microbiota consists of various microorganisms including bacteria, fungi, viruses, and archaea; the gut microbiota is comprised mostly of bacteria. Many bacterial species within the gut microbiome grow as biofilms, which are multicellular communities embedded in an extracellular matrix.

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Reactive arthritis, an autoimmune disorder, occurs following gastrointestinal infection with invasive enteric pathogens, such as Salmonella enterica. Curli, an extracellular, bacterial amyloid with cross beta-sheet structure can trigger inflammatory responses by stimulating pattern recognition receptors. Here we show that S.

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Bacterial biofilms, especially those associated with implanted medical devices, are difficult to eradicate. Curli amyloid fibers are important components of the biofilms formed by the Enterobacteriaceae family. Here, we show that a human monoclonal antibody with pan-amyloid-binding activity (mAb 3H3) can disrupt biofilms formed by Salmonella enterica serovar Typhimurium in vitro and in vivo.

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produce amyloid proteins called curli that are the major proteinaceous component of biofilms. Amyloids are also produced by humans and are associated with diseases such as Alzheimer's. During the multistep process of amyloid formation, monomeric subunits form oligomers, protofibrils, and finally mature fibrils.

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In this chapter several aspects of Pt(II) are highlighted that focus on the properties of Pt(II)-RNA adducts and the possibility that they influence RNA-based processes in cells. Cellular distribution of Pt(II) complexes results in significant platination of RNA, and localization studies find Pt(II) in the nucleus, nucleolus, and a distribution of other sites in cells. Treatment with Pt(II) compounds disrupts RNA-based processes including enzymatic processing, splicing, and translation, and this disruption may be indicative of structural changes to RNA or RNA-protein complexes.

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Purpose: To improve lingual ultrasound imaging with the corrected high frame rate anchored ultrasound with software alignment (CHAUSA; Miller, 2008) method.

Method: A production study of the IsiXhosa alveolar click is presented. Articulatory-to-acoustic alignment is demonstrated using a Tri-Modal 3-ms pulse generator.

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