Widespread antibiotic resistance among important bacterial pathogens such as Staphylococcus aureus1 calls for alternative routes of drug development. Interfering with critical virulence determinants is considered a promising novel approach to control bacterial infection2. Phenol-soluble modulins (PSMs) are peptide toxins with multiple key roles in pathogenesis3–5 and a major impact on the ability of highly virulent S. aureus to cause disease3,6. However, targeting PSMs for therapeutic intervention is hampered by their multitude and diversity. Here, we report that an ABC transporter with previously unknown function is responsible for the export of all PSM classes, thus representing a single target to interfere simultaneously with the production of all PSMs. The transporter had a strong effect on virulence phenotypes, such as neutrophil lysis, and the development of S. aureus infection, similar in extent to the sum of all PSMs. Furthermore, it proved essential for bacterial growth. Moreover, it protected the producer from the antimicrobial activity of secreted PSMs and contributed to defense against PSM-mediated bacterial interference. Our study reveals a non-canonical, dedicated secretion mechanism for an important toxin class and identifies this mechanism as a comprehensive potential target for the development of drugs efficiently inhibiting growth and virulence of pathogenic staphylococci.

Antibiotic prescribing practices across the VA experienced significant shifts during the coronavirus (COVID-19) pandemic. From 2015 to 2019, antibiotic use between January – May decreased from 638 to 602 DOT/1000 DP, while the corresponding months in 2020 saw antibiotic utilization rise to 628 DOT/1000 DP.

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Background Isavuconazole and posaconazole are commonly used for both prophylaxis and treatment of invasive fungal infections. These agents are formulated for oral administration as a capsule and delayed release (DR) tablet or suspension, respectively. In patients unable to swallow, alternative means of administration, such as crushing posaconazole DR tablets and opening isavuconazole capsules, may be used to avoid IV administration or use of posaconazole suspension, which often produces subtherapeutic concentrations. Objectives To assess the feasibility of achieving target plasma drug concentrations with enteral feeding tube (EFT) administration of crushed posaconazole DR tablets and opened isavuconazole capsules. Methods We retrospectively reviewed pharmacy records to identify patients receiving EFT administration of posaconazole or isavuconazole with concurrent therapeutic drug monitoring from October 2019 to June 2021. Plasma concentrations of either agent as well as clinical outcomes were documented. Results We identified 37 patients receiving 38 courses of EFT isavuconazole or posaconazole. The majority of patients received primary prophylaxis following lung transplantation (64.9%). Plasma concentrations upon first assessment were therapeutic in the majority of patients (posaconazole 71.5%, isavuconazole 83.3%) with a mean level of 1.61 ± 0.77 mg/L for posaconazole and 2.07 ± 1.1 mg/L for isavuconazole. Of those that were subtherapeutic on initial assessment, all but one subsequently achieved target levels upon dose titration. Standard maintenance doses were used in all isavuconazole and most posaconazole patients. Conclusions Our case series demonstrates that isavuconazole and posaconazole can be administered via EFT with concurrent therapeutic drug monitoring to achieve target plasma concentrations in the majority of patients.