Complete genome sequence of B273 and its epidermicin NI01 biosynthesis plasmid.

The human skin commensal produces diverse, therapeutically relevant bacteriocins. We report the complete whole-genome sequence of the nasal isolate B273, which contains a plasmid with the biosynthetic gene cluster for epidermicin NI01, a broad-spectrum type II antimicrobial peptide.

Evaluation of plasma activated liquids for the elimination of mixed species biofilms within endoscopic working channels.

The use of reusable flexible endoscopes has increased dramatically over the past decade, however despite improvements in endoscope reprocessing, the continued emergence of endoscopy-associated outbreaks as a result of multi-drug resistant bacteria has highlighted the need for a new approach to disinfection. Here, the use of plasma activated liquids (PALs) for the elimination of mixed species biofilm contamination within the working channels of endoscopes was evaluated. Cold atmospheric pressure plasma was used to chemically activate water and a commercially available pH buffered peracetic acid to create PALs.

Benchmarking classification abilities of novel optical photothermal IR spectroscopy at the single-cell level with bulk FTIR measurements.

Fourier-transform infrared (FTIR) spectroscopy is a simple, fast and inexpensive method with a history of use for bacterial analysis. However, due to the limitations placed on spatial resolution inherent to infrared wavelengths, analysis has generally been performed on bulk samples, leading to biological variance among individual cells to be buried in averaged spectra. This also increases the bacterial load necessary for analysis, which can be problematic in clinical settings where limiting incubation time is valuable.

Microbial keratitis in Southern Malawi: a microbiological pilot study.

Objective: Microbial keratitis (MK) is a significant cause of blindness in sub-Saharan Africa. We investigated the feasibility of using a novel corneal impression membrane (CIM) for obtaining and processing samples by culture, PCR and whole-genome sequencing (WGS) in patients presenting with suspected MK in Malawi.

Methods And Analysis: Samples were collected from patients presenting with suspected MK using a 12 mm diameter polytetrafluoroethylene CIM disc.

Bacteriophages from human skin infecting coagulase-negative Staphylococcus: diversity, novelty and host resistance.

The human skin microbiome comprises diverse populations that differ temporally between body sites and individuals. The virome is a less studied component of the skin microbiome and the study of bacteriophages is required to increase knowledge of the modulation and stability of bacterial communities. Staphylococcus species are among the most abundant colonisers of skin and are associated with both health and disease yet the bacteriophages infecting the most abundant species on skin are less well studied.

Commensal production of a broad-spectrum and short-lived antimicrobial peptide polyene eliminates nasal Staphylococcus aureus.

Antagonistic bacterial interactions often rely on antimicrobial bacteriocins, which attack only a narrow range of target bacteria. However, antimicrobials with broader activity may be advantageous. Here we identify an antimicrobial called epifadin, which is produced by nasal Staphylococcus epidermidis IVK83.

Bioprospecting the Skin Microbiome: Advances in Therapeutics and Personal Care Products.

Bioprospecting is the discovery and exploration of biological diversity found within organisms, genetic elements or produced compounds with prospective commercial or therapeutic applications. The human skin is an ecological niche which harbours a rich and compositional diversity microbiome stemming from the multifactorial interactions between the host and microbiota facilitated by exploitable effector compounds. Advances in the understanding of microbial colonisation mechanisms alongside species and strain interactions have revealed a novel chemical and biological understanding which displays applicative potential.

Compositional Variations between Adult and Infant Skin Microbiome: An Update.

Human skin and its commensal microbiome form the first layer of protection to the outside world. A dynamic microbial ecosystem of bacteria, fungi and viruses, with the potential to respond to external insult, the skin microbiome has been shown to evolve over the life course with an alteration in taxonomic composition responding to altered microenvironmental conditions on human skin. This work sought to investigate the taxonomic, diversity and functional differences between infant and adult leg skin microbiomes.

Comparative genomics of reveals species determinants.

is primarily described as a human skin commensal but is now emergent as an opportunistic pathogen isolated from the bloodstream and prosthetic joint infections, and neonatal intensive care unit (NICU)-associated sepsis. We used comparative genomic analyses of to provide new insights into commensal scalp isolates from varying skin states (healthy, dandruff lesional, and non-lesional), and to expand our current knowledge of the species populations (scalp isolates, = 59; other skin isolates, = 7; publicly available isolates, = 120). A highly recombinogenic population structure was revealed, with genomes including the presence of a range of previously described staphylococcal virulence factors, cell wall-associated proteins, and two-component systems.

Selection of in a murine nasopharyngeal colonization model.

nasal colonization is a risk factor for infection. A large proportion of the population are identified as potential carriers yet we only partially understand the repertoire of genetic factors that promote long-term nasal colonization. Here we present a murine model of nasopharyngeal colonization that requires a low inoculum and is amenable to experimental evolution approaches.

Amoebicidal Activity of Poly-Epsilon-Lysine Functionalized Hydrogels.

Purpose: To determine the amoebicidal activity of functionalized poly-epsilon-lysine hydrogels (pɛK+) against Acanthamoeba castellanii.

Methods: A. castellanii trophozoites and cysts were grown in the presence of pɛK solution (0-2.

Bacterial keratitis: identifying the areas of clinical uncertainty.

Bacterial keratitis is a common corneal infection that is treated with topical antimicrobials. By the time of presentation there may already be severe visual loss from corneal ulceration and opacity, which may persist despite treatment. There are significant differences in the associated risk factors and the bacterial isolates between high income and low- or middle-income countries, so that general management guidelines may not be appropriate.

Transcriptomic Responses and Survival Mechanisms of Staphylococci to the Antimicrobial Skin Lipid Sphingosine.

Sphingosines are antimicrobial lipids that form part of the innate barrier to skin colonization by microbes. Sphingosine deficiencies can result in increased epithelial infections by bacteria including Staphylococcus aureus. Recent studies have focused on the potential use of sphingosine resistance or its potential mechanisms.

An Evaluation of a Simplified Impression Membrane Sampling Method for the Diagnosis of Microbial Keratitis.

The purpose of this study was to compare bacterial isolation rate using a corneal impression membrane (CIM) and a sharp instrument for obtaining corneal samples from patients with suspected microbial keratitis (MK). Data was retrospectively collected for all patients that had corneal samples taken for presumed MK between May 2014 and May 2020. Prior to May 2017 samples were collected by scraping the edges of the ulcer with a blade.

Recurrent microbial keratitis and endogenous site Staphylococcus aureus colonisation.

This study investigated Staphylococcus aureus carriage in patients with microbial keratitis (MK). 215 patients with MK, 60 healthy controls and 35 patients with rheumatoid arthritis (RA) were included. Corneal scrapes were collected from patients with MK.

Antimicrobial Activity of Poly-epsilon-lysine Peptide Hydrogels Against Pseudomonas aeruginosa.

Purpose: To determine the antimicrobial activity of poly-epsilon-lysine (pɛK) functionalization of hydrogels against Pseudomonas aeruginosa.

Methods: Antimicrobial activities of pɛK and pɛK+ hydrogels were tested against both keratitis and a laboratory strain of Paeruginosa at a range of inocula sizes, over 4 and 24 hours. The number of viable CFU on pɛK and pɛK+ hydrogels or commercial contact lenses (CL) was investigated.

Toxin-mediated competition in weakly motile bacteria.

Many bacterial species produce toxins that inhibit their competitors. We model this phenomenon by extending classic two-species Lotka-Volterra competition in one spatial dimension to incorporate toxin production by one species. Considering solutions comprising two adjacent single-species colonies, we show how the toxin inhibits the susceptible species near the interface between the two colonies.

Comparative Genomics of Reveals Determinants of Speciation and Diversification of Antimicrobial Defense.

The bacterial genus comprises diverse species with most being described as colonizers of human and animal skin. A relational analysis of features that discriminate its species and contribute to niche adaptation and survival remains to be fully described. In this study, an interspecies, whole-genome comparative analysis of 21 species was performed based on their orthologues.

Whole-Genome Sequence of Strain J31 Isolated from Healthy Human Skin.

We report here the first whole-genome sequence of a skin-associated strain of determined using the PacBio long-read sequencing platform. is a major commensal of the skin microflora. This genome sequence adds to our understanding of this species and will aid studies of gene traffic between staphylococci.

Comparative Transcriptomics Reveals Discrete Survival Responses of and to Sapienic Acid.

Staphylococcal colonization of human skin is ubiquitous, with particular species more frequent at different body sites. Whereas can be isolated from the skin of every individual tested, is isolated from <5% of healthy individuals. The factors that drive staphylococcal speciation and niche selection on skin are incompletely defined.

Deferred Growth Inhibition Assay to Quantify the Effect of Bacteria-derived Antimicrobials on Competition.

Competitive exclusion can occur in microbial communities when, for example, an inhibitor-producing strain outcompetes its competitor for an essential nutrient or produces antimicrobial compounds that its competitor is not resistant to. Here we describe a deferred growth inhibition assay, a method for assessing the ability of one bacterium to inhibit the growth of another through the production of antimicrobial compounds or through competition for nutrients. This technique has been used to investigate the correlation of nasal isolates with the exclusion of particular species from a community.

A Novel Peptide Hydrogel for an Antimicrobial Bandage Contact Lens.

A peptide hydrogel with an antimicrobial activity is developed as a bandage contact lens. The antimicrobial activity is enhanced with the addition of the biomolecules penicillin G or poly-ε-lysine and is positive against Staphylococcus aureus and Escherichia coli. The lens is also noncytotoxic toward a human corneal epithelial cell line and as a consequence is of great potential as a drug-eluting bandage lens replacing conventional corneal ulcer treatment.

Rapid evolution of microbe-mediated protection against pathogens in a worm host.

Microbes can defend their host against virulent infections, but direct evidence for the adaptive origin of microbe-mediated protection is lacking. Using experimental evolution of a novel, tripartite interaction, we demonstrate that mildly pathogenic bacteria (Enterococcus faecalis) living in worms (Caenorhabditis elegans) rapidly evolved to defend their animal hosts against infection by a more virulent pathogen (Staphylococcus aureus), crossing the parasitism-mutualism continuum. Host protection evolved in all six, independently selected populations in response to within-host bacterial interactions and without direct selection for host health.

Whole-Genome Sequence of Staphylococcus epidermidis Tü3298.

Staphylococcus epidermidis Tü3298 is a frequently used laboratory strain, known for its production of epidermin and absence of the icaABCD operon. We report the whole-genome sequence of this strain, a 2.5-kb genome containing 2,332 genes.