Still not sterile: viability-based assessment of the skin microbiome following pre-surgical application of a broad-spectrum antiseptic reveals transient pathogen enrichment and long-term recovery

Microbiology Spectrum, Journal Year: 2025, Volume and Issue: unknown

Published: April 10, 2025

ABSTRACT Broad-spectrum antiseptics such as chlorhexidine gluconate (CHG) have widespread use pre-surgical tools to lower skin microbial burden and reduce the risk of surgical site infection. However, short- long-term effects CHG on healthy communities remain undefined due confounding binding with persistent bacterial DNA surface. Here, we aim accurately characterize immediate impact preparation CHG-based human microbiome. Twenty-eight patients undergoing elective surgeries were enrolled. Swabs a control microbiome collected at multiple time points before up 2 weeks after surgery. A propidium monoazide (PMAxx)-based viability assay was optimized selectively evaluate from live microbes in complex viability-qPCR viable 16S ribosomal RNA gene profiling. Pre-operative induces measurable reduction bioburden site. On day surgery, sites displayed significant increase relative abundance several SSI-associated genera including Acinetobacter, Bacillus, Escherichia-Shigella, Pseudomonas compared baseline. Bacillus species isolated subjects baseline also demonstrate resistance minimum inhibitory concentrations exceeding 1,000 µg/mL. Although there are major shifts upon exposure CHG, find that these largely transient. For majority individuals, community structure recover near by post-surgical follow-up. IMPORTANCE Surgical infections continue occur despite adoption antiseptics. Before often wash their whole body times (CHG)-based antiseptic soap applied operating room. persisting dead cells skin. We target CHG. Our findings application significantly reduces skin; however, potentially pathogenic bacteria remain. Post-surgery, eventually recovers resemble its pre-CHG exposed state. Collectively, identify tangible avenues for improving formulations further support is viable, stable, resilient chemical perturbation.

Language: Английский

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Abundance measurements reveal the balance between lysis and lysogeny in the human gut microbiome

Current Biology, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

Language: Английский

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Highly-resolved within-species dynamics in the human facial skin microbiome

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 10, 2024

Adult human facial skin microbiomes are remarkably similar at the species-level, dominated by Cutibacterium acnes and Staphylococcus epidermidis, yet each person harbors a unique community of strains. Understanding how person-specific communities assemble is critical for designing microbiome-based therapies. Here, using 4,055 isolate genomes 360 metagenomes, we reconstruct on-person evolutionary history to reveal on between-person strain dynamics. We find that multiple cells typically involved in transmission, indicating ample opportunity migration. Despite this accessibility, family members share only some their S. epidermidis dynamic, with persisting an average 2 years. C. strains more stable have higher colonization rate during transition adult microbiome, suggesting window could facilitate engraftment therapeutic These previously undetectable dynamics may influence design microbiome therapeutics motivate study effects hosts.

Language: Английский

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Cutaneous Surgical Wounds Have Distinct Microbiomes from Intact Skin

Microbiology Spectrum, Journal Year: 2022, Volume and Issue: 11(1)

Published: Dec. 21, 2022

Infections are relatively rare following cutaneous surgical procedures, despite the potential for wound exposure to pathogens both during surgery and throughout healing process. Although gut commensals believed reduce risk of intestinal infections, an analogous role skin has not been described. In fact, microbiome normally wounds yet profiled using culture-independent techniques. We characterized in 53 patients who underwent cancer healed without signs or symptoms infection. A week after surgery, several bacterial species displayed significant differences relative abundance when compared control, nonoperated from same patient. The most common bacterium found on intact skin, Cutibacterium acnes, was reduced 5-fold. Staphylococcus aureus, a frequent cause postoperative enriched 6.4-fold clinically noninfected wounds, suggesting active suppression pathogenicity. Finally, members

Language: Английский

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Still Not Sterile: Chlorhexidine gluconate treatment does not completely reduce skin microbial bioburden and promotes pathogen overabundance in patients undergoing elective surgeries.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: July 21, 2024

Abstract Surgical site infections (SSI) continue to occur despite widespread adoption of surgical antiseptics. The effects chlorhexidine gluconate (CHG)-based antiseptics on the skin microbiome also remains undefined due confounding CHG persistence skin. Patients undergoing elective surgery were enrolled characterize immediate and long-term impact pre-surgical preparation with antiseptic microbial communities. Due broad-spectrum antimicrobial activity its propensity bind extracellular DNA, methods selectively identify live microorganisms are critical this process fully elucidate effectiveness protocols potential disruptions healthy microbiome. Swabs collected at multiple timepoints before after surgery. Microbial bioburden community compositions evaluated viability qPCR 16S ribosomal RNA gene profiling. Pre-operative induced a measurable reduction in viable site. On day surgery, sites displayed significant increase relative abundance several SSI associated bacterial genera, including , Acinetobacter, Bacillus, Escherichia-Shigella, Pseudomonas compared baseline . Bacillus species isolated from subjects showed resistance MICs exceeding 1000 µg/ml. Despite major shifts upon exposure CHG, they transient majority individuals. Skin structure recovered by post-surgical follow-up. In short, study shows that application can significantly reduce bioburden, however, complete sterility is not achieved. While induces temporary microbiome, enrichment for potentially pathogenic taxa, recovers back near baseline. Collectively, these findings tangible avenues improving formulations offer further support viable, stable, resilient chemical perturbation.

Language: Английский

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Abundance measurements reveal the balance between lysis and lysogeny in the human gut microbiome

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 27, 2024

The human gut contains diverse communities of bacteriophage, whose interactions with the broader microbiome and potential roles in health are only beginning to be uncovered. Here, we combine multiple types data quantitatively estimate phage population dynamics lifestyle characteristics subjects. Unifying results from previous studies, show that an average a low ratio particles bacterial cells (~1:100), but much larger genomes (~4:1), implying most effectively temperate (e.g., integrated prophage, phage-plasmids, etc.). By integrating imaging sequencing generalized model dynamics, induction lysis occurs at rate (~0.001-0.01 per bacterium day), imposing modest fitness burden on their hosts. Consistent these estimates, find composition synthetic community gnotobiotic mice can predicted abundances alone, while still exhibiting diversity comparable native microbiomes. These provide foundation for interpreting existing future studies links between virome health.

Language: Английский

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Intraspecies warfare restricts strain coexistence in human skin microbiomes

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: May 7, 2024

Determining why only a fraction of encountered or applied bacterial strains engraft in given person's microbiome is crucial for understanding and engineering these communities

Language: Английский

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Diversity of Neurotransmitter Producing Human Skin Commensals

Published: Oct. 24, 2024

Recent findings indicate that human microbiota can excrete trace amines, dopamine, and serotonin. These neurotransmitters (NTs) either affect classical neurotransmitter signaling or directly trigger amine-associated receptors (TAARs), with still unclear consequences for host physiology. Compared to gut microbiota, less information is available on the role of skin in NT production. To explore this, 1909 isolates, mainly from genera Staphylococcus, Bacillus, Corynebacterium, were tested Only 6.7% isolates capable producing NTs, all which belonged Staphylococcus genus. Based substrate specificity, we identified two distinct profiles among producers. One group primarily produced tryptamine (TRY) phenylethylamine (PEA), while other tyramine (TYM) dopamine (Dopa). differing production could be attributed activity aromatic amino acid decarboxylase enzymes, SadA TDC, responsible generating TRY/PEA TYM/Dopa product spectra, respectively. TDC orthologues differ structure size; has approximately 475 acids, whereas TDC-type consists about 620 acids. The genomic localization respective genes also varies: tdc are typically found small, conserved gene clusters, sadA not. Heterologous expression Escherichia coli yielded same spectrum as parent strains. possible effects microbiota-derived NTs neuroreceptor remain investigated.

Language: Английский

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Facultatively Anaerobic Staphylococci Enable Anaerobic Cutibacterium Species to Grow and Form Biofilms Under Aerobic Conditions

Microorganisms, Journal Year: 2024, Volume and Issue: 12(12), P. 2601 - 2601

Published: Dec. 16, 2024

Facultatively anaerobic Staphylococcus spp. and Cutibacterium are among the most prominent bacteria on human skin. Although skin microbes generally grow as multispecies biofilms, few studies have investigated interaction between staphylococci in dual-species biofilms. Here, we measured mono- biofilm formation of four staphylococcal species (S. epidermidis, S. hominis, capitis, aureus) two (C. acnes C. avidum) cultured vitro under both aerobic conditions. The biofilms were quantitated by rinsing them to remove planktonic cells, detaching via sonication, enumerating cells dilution plating. When alone, formed conditions, whereas only In co-culture, was unaffected presence spp., regardless oxygen availability. However, significantly enhanced staphylococci, enabling robust growth Fluorescence confocal microscopy suggested that create niches at base where can grow. These findings demonstrate facilitate colonization oxygen-rich environments, potentially explaining their high numbers oxygen-exposed stratum corneum.

Language: Английский

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Bacterial viability in the built environment of the home

PLoS ONE, Journal Year: 2023, Volume and Issue: 18(11), P. e0288092 - e0288092

Published: Nov. 8, 2023

The built environment (BE) consists of human-made structures and, much like living organisms, is colonized by bacteria that make up the BE microbiome. microbiome can potentially affect human health because constant proximity these to humans. This has led increasing public concern whether in are harmful. Previous studies have used approaches based on DNA sequencing assess composition However, extent which bacterial represents viable cells could infect hosts remains unknown. To address this open question we both culture-based and culture-independent molecular methods profile viability microbiomes from several sites. As part an undergraduate-led project, found vast majority not associated with bacteria, suggesting most dead. begin understand determinants mock communities investigate effects temperature, relative humidity, interaction viability. We surface material did statistically significant viability, but environmental exposure decreased These results update our conception define factors

Language: Английский

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