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Abstract Staphylococcus aureusis an opportunistic pathogen frequently detected in environmental waters and commonly causes skin infections to water users.S. aureusconcentrations in fresh, brackish, and marine waters are positively correlated with water turbidity. To reduce the risk ofS. aureusinfections from environmental waters,S. aureussurvival (stability and multiplication) in turbid waters needs to be investigated. The aim of this study was to measureS. aureusin turbid fresh and brackish water samples and compare the concentrations over time to determine which conditions are associated with enhancedS. aureussurvival. Eighteen samples were collected from fresh and brackish water sources from two different sites on the east side of Oʻahu, Hawaiʻi.S. aureuswas detected in microcosms for up to 71 days with standard microbial culturing techniques. On average, the greatest environmental concentrations ofS. aureuswere in high turbidity fresh waters followed by high turbidity brackish waters. Models demonstrate that salinity and turbidity significantly predict environmentalS. aureusconcentrations.S. aureuspersistence over the extent of the experiment was the greatest in high turbidity microcosms with T90's of 147.8 days in brackish waters and 80.8 days in freshwaters. This study indicates that saline, turbid waters, in the absence of sunlight, provides suitable conditions for enhanced persistence ofS. aureuscommunities that may increase the risk of exposure in environmental waters. Practitioner PointsStaphylococcus aureusconcentrations, survival, and persistence were assessed in environmental fresh and brackish waters.Experimental design preserved in situ conditions to measureS. aureussurvival.Higher initialS. aureusconcentrations were observed in fresh waters with elevated turbidity, while sustained persistence was greater in brackish waters.Water turbidity and salinity were both positively associated withS. aureusconcentrations and persistence.Climate change leads to more intense rainfall events which increase water turbidity and pathogen loading, heightening the exposure risk toS. aureus.
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Complete Genome Sequence of Staphylococcus aureus Siphophage Lorac
ABSTRACT Staphylococcus aureus is a leading cause of a wide range of clinical infections. Here, we announce the complete genome sequence of S. aureus siphophage Lorac, a phiETA-like temperate phage that is similar at the nucleotide level to the previously described S. aureus prophage phiNM2.
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- Award ID(s):
- 1749886
- PAR ID:
- 10128592
- Date Published:
- Journal Name:
- Microbiology Resource Announcements
- Volume:
- 8
- Issue:
- 27
- ISSN:
- 2576-098X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1128/MRA.00586-19
