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Fenical, W.

Publications and source records attributed to Fenical, W..

3 recordsLinked to original sources

An extremophilic Nocardiopsis strain from Great Salt Lake expands the taxonomic range of mycolic acid biosynthesis

Mycolic acids, long-chain fatty acids that form the characteristic and relatively impermeable mycomembrane, have long been considered a defining chemotaxonomic feature of the order Mycobacteriales. Here, we report that Nocardiopsis bonnevillensis, a new type strain isolated from the hypersaline environment of Great Salt Lake, is the first organism outside of this order known to produce mycolic acids. Lipid profiling, acid-fast staining, isoniazid sensitivity, and genome mining confirmed hallmark features of mycolic acid biosynthesis. Evaluation of the strains metabolic capabilities led to the isolation of bonnevanoside, a thiophenyl nonulopyranoside reported here for the first time from a natural source. Moreover, additional Great Salt Lake-derived Nocardiopsis isolates exhibited acid-fast staining, suggesting that this trait may be more widespread than previously recognized. Altogether, these findings expand the taxonomic distribution of mycolic acid biosynthesis, challenge long-standing chemotaxonomic boundaries, and highlight the potential ecological significance of mycolate-containing envelopes in supporting bacterial survival in extreme environments.

microbiology↗

Bacterial Diversity and Chemical Ecology of Natural Product-Producing Bacteria from Great Salt Lake Sediment

Great Salt Lake (GSL), located northwest of Salt Lake City, UT, is the largest terminal lake in the United States. While the average salinity of seawater is [~]3.3%, the salinity in GSL ranges between 5-28%. In addition to being a hypersaline environment, GSL also contains toxic concentrations of heavy metals, such as arsenic, mercury, and lead. The extreme environment of GSL makes it an intriguing subject of study, both for its unique microbiome and its potential to harbor novel natural product-producing bacteria, which could be used as resources for the discovery of biologically active compounds. Though work has been done to survey and catalogue bacteria found in GSL, the Lakes microbiome is largely unexplored, and little-to-no work has been done to characterize the natural product potential of GSL microbes. Here, we investigate the bacterial diversity of two important regions within GSL, describe the first genomic characterization of Actinomycetota isolated from GSL sediment, including the identification of a new Saccharomonospora species, and provide the first survey of the natural product potential of GSL bacteria.

ecology↗

Nanoscaled discovery of a shunt rifamycin from Salinispora arenicola using a three-colour GFP-tagged Staphylococcus aureus macrophage infection assay.

Antimicrobial resistance has emerged as an urgent global public health threat, and development of novel therapeutics for treating infections caused by multi-drug resistant bacteria is urgent. Staphylococcus aureus is a major human and animal pathogen, responsible for high levels of morbidity and mortality worldwide. The intracellular survival of S. aureus in macrophages contributes to immune evasion, dissemination, and resilience to antibiotic treatment. Here, we present a confocal fluorescence imaging assay for monitoring macrophage infection by GFP-tagged Staphylococcus aureus as a front-line tool to identify antibiotic leads. The assay was employed in combination with nanoscaled chemical analyses to facilitate the discovery of a novel, active rifamycin analogue. Our findings indicate a promising new approach to the identification of anti-microbial compounds with macrophage intracellular activity. The novel antibiotic identified here may represent a useful addition to our armoury in tackling the silent pandemic of antimicrobial resistance.

cell biology↗