Publications by authors named "Miranda Wallace"

Gastrointestinal colonization by Clostridioides difficile is common in healthcare settings and ranges in presentation from asymptomatic carriage to lethal C. difficile infection (CDI). We used a systems biology approach to investigate why patients colonized with C.

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Engineered probiotics are an emerging platform for in situ delivery of therapeutics to the gut. Herein, we developed an orally administered, yeast-based therapeutic delivery system to deliver next-generation immune checkpoint inhibitor (ICI) proteins directly to gastrointestinal tumors. We engineered Saccharomyces cerevisiae var.

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Gastrointestinal colonization by is common in healthcare settings and ranges in clinical presentation from asymptomatic carriage to lethal infection (CDI). We used a systems biology approach to investigate why patients colonized with have a range of outcomes. Microbiota-humanization of germ-free mice with fecal samples from toxigenic C.

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Bacteroides fragilis group (BFG) species are common members of the human microbiota that provide several benefits to healthy hosts, yet BFG are also the most common anaerobes isolated from human infections, including intra-abdominal infections, abscesses, and bloodstream infection. Compared to many other anaerobes associated with disease, members of the BFG are more likely to be resistant to commonly used antimicrobials, including penicillin (>90% resistant), carbapenems (2 to 20% resistant), and metronidazole (0.2 to 4% resistant).

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Infections due to Gram-negative bacteria are increasingly dangerous due to the spread of multi-drug resistant strains, emphasizing the urgent need for new antibiotics with alternative modes of action. We have previously identified a novel class of antibacterial agents, thioacetamide-triazoles, using an antifolate targeted screen and determined their mode of action which is dependent on activation by cysteine synthase A. Herein, we report a detailed examination of the anti- structure-activity relationship of the thioacetamide-triazoles.

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Bacteroides fragilis group (BFG) are the most frequently recovered anaerobic bacteria from human infections, and resistance to frontline antibiotics is emerging. In the absence of routine antimicrobial susceptibility testing (AST) for BFG in most clinical settings, we assessed the utility of clinical and modern genomics tools to determine BFG species-level identification and resistance patterns. A total of 174 BFG clinical isolates supplemented with 20 archived carbapenem-resistant B.

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The peptide binding protein DppA is an ABC transporter found in prokaryotes that has the potential to be used as drug delivery tool for hybrid antibiotic compounds. Understanding the motifs and structures that bind to DppA is critical to the development of these bivalent compounds. This study focused on the biophysical analysis of the MtDppA from M.

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Although Bordetella hinzii coccobacilli is most commonly identified in respiratory tracts of birds and rodents, this organism has occasionally been isolated in human infections. We describe a case of B. hinzii spontaneous bacterial peritonitis in Missouri, USA.

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Multidrug-resistant bacteria are causing a serious global health crisis. A dramatic decline in antibiotic discovery and development investment by pharmaceutical industry over the last decades has slowed the adoption of new technologies. It is imperative that we create new mechanistic insights based on latest technologies, and use translational strategies to optimize patient therapy.

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Increasing rates of drug-resistant Gram-negative (GN) infections, combined with a lack of new GN-effective antibiotic classes, are driving the need for the discovery of new agents. Bacterial metabolism represents an underutilized mechanism of action in current antimicrobial therapies. Therefore, we sought to identify novel antimetabolites that disrupt key metabolic pathways and explore the specific impacts of these agents on bacterial metabolism.

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Acyldepsipeptides are a unique class of antibiotics that act via allosterically dysregulated activation of the bacterial caseinolytic protease (ClpP). The ability of ClpP activators to kill nongrowing bacteria represents a new opportunity to combat deep-seated biofilm infections. However, the acyldepsipeptide scaffold is subject to rapid metabolism.

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Staphylococcal species are a leading cause of bacterial drug-resistant infections and associated mortality. One strategy to combat bacterial drug resistance is to revisit compromised targets, and to circumvent resistance mechanisms using structure-assisted drug discovery. The folate pathway is an ideal candidate for this approach.

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Herein we report the antibacterial structure-activity relationships of cyclic hexapeptide wollamide analogs derived from solid-phase library synthesis. Wollamide B, a cyclic hexapeptide natural product, has been previously found to have activity against Mycobacterium bovis. To further evaluate its antimycobacterial/antibacterial potential, 27 peptides including wollamides A/B, and desotamide B, were synthesized and subsequently tested against a panel of clinically significant bacterial pathogens.

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In an effort to develop new fluoroquinolones, we synthesized eight compounds and tested them against a panel of bacteria. The design of these compounds was guided by the introduction of the isothiazoloquinolone motif. The three most active compounds in this series, 8-10, demonstrated good antibacterial activity against methicillin-sensitive Staphylococcus aureus and healthcare-acquired methicillin-resistant Staphylococcus aureus (MIC 0.

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The sulfonamide class of antibiotics has been in continuous use for over 70years. They are thought to act by directly inhibiting dihydropteroate synthase (DHPS), and also acting as prodrugs that sequester pterin pools by forming dead end pterin-sulfonamide conjugates. In this study, eight pterin-sulfonamide conjugates were synthesized using a novel synthetic strategy and their biochemical and microbiological properties were investigated.

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Context: The phenotypic effects of ADIPOQ mutations early in life, prior to type 2 diabetes onset, have not been studied.

Aim: The objective of the study was to characterize the impact of a novel ADIPOQ mutation in vitro and in vivo.

Design: The design of the study was ADIPOQ screening, adiponectin oligomerization, and cardiometabolic phenotype assessment.

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