Publications by authors named "Samantha Halliwell"

Bacteriocins are a distinct family of antimicrobial proteins postulated to porate bacterial membranes. However, direct experimental evidence of pore formation by these proteins is lacking. Here we report a multi-mode poration mechanism induced by four-helix bacteriocins, epidermicin NI01 and aureocin A53.

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Background: The secretion of recombinant disulfide-bond containing proteins into the periplasm of Gram-negative bacterial hosts, such as E. coli, has many advantages that can facilitate product isolation, quality and activity. However, the secretion machinery of E.

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The ability of RNA to sense, regulate, and store information is an attractive attribute for a variety of functional applications including the development of regulatory control devices for synthetic biology. RNA folding and function is known to be highly context sensitive, which limits the modularity and reuse of RNA regulatory devices to control different heterologous sequences and genes. We explored the cause and effect of sequence context sensitivity for translational ON riboswitches located in the 5' UTR, by constructing and screening a library of N-terminal synonymous codon variants.

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The apparent mislocalization or excretion of cytoplasmic proteins is a commonly observed phenomenon in both bacteria and eukaryotes. However, reports on the mechanistic basis and the cellular function of this so-called "nonclassical protein secretion" are limited. Here we report that protein overexpression in recombinant cells and antibiotic-induced translation stress in wild-type cells both lead to excretion of cytoplasmic protein (ECP).

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Objectives: To investigate the efficacy of a potent novel antimicrobial protein of mass 6 kDa, epidermicin NI01, for eradicating the nasal burden of MRSA in a cotton rat ( Sigmodon hispidus ) model.

Methods: MRSA strain ATCC 43300 was used to establish a robust colonization of cotton rat nares. This model was used to evaluate the efficacy of topical 0.

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The ability to induce gene expression in a small molecule dependent manner has led to many applications in target discovery, functional elucidation and bio-production. To date these applications have relied on a limited set of protein-based control mechanisms operating at the level of transcription initiation. The discovery, design and reengineering of riboswitches offer an alternative means by which to control gene expression.

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We investigated the relevance of gene expression heterogeneity to virulence properties of a major fungal pathogen, Candida glabrata. The organism's key virulence-associated factors include glycosylphosphatidylinositol-anchored adhesins, encoded subtelomerically by the EPA gene family. Individual-cell analyses of expression revealed very striking heterogeneity for Epa1, an adhesin that mediates ∼95% of adherence to epithelial cells in vitro.

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