Biodiversity, Bioactivity, and Metabolites of High Desert Derived Oregonian Soil Bacteria

Abstract

From arid, high desert soil samples collected near Bend, Oregon, 19 unique bacteria were isolated. Each strain was identified by 16S rRNA gene sequencing, and their organic extracts were tested for antibacterial and antiproliferative activities. Noteworthy, six extracts (30 %) exhibited strong inhibition resulting in less than 50 % cell proliferation in more than one cancer cell model, tested at 10 μg/mL. Principal component analysis (PCA) of LC/MS data revealed drastic differences in the metabolic profiles found in the organic extracts of these soil bacteria. In total, fourteen potent antibacterial and/or cytotoxic metabolites were isolated via bioactivity‐guided fractionation, including two new natural products: a pyrazinone containing tetrapeptide and 7‐methoxy‐2,3‐dimethyl‐4H‐chromen‐4‐one, as well as twelve known compounds: furanonaphthoquinone I, bafilomycin C1 and D, FD‐594, oligomycin A, chloramphenicol, MY12‐62A, rac‐sclerone, isosclerone, tunicamycin VII, tunicamycin VIII, and (6S,16S)‐anthrabenzoxocinone 1.264‐C.

Antibacterial, Antifungal and Anticancer Activities of Compounds Produced by Newly Isolated Streptomyces Strains from the Szczelina Chochołowska Cave (Tatra Mountains, Poland)

“…In addition, antibiotic activities of natural anthrabenzoxocinones can be enhanced by biochemical modifications [31]. Furthermore, recent studies highlighted a high biodiversity of natural products, including anthrabenzoxocinone compounds, produced by bacteria isolated from natural habitats [32], and a high genetic potential of Streptomyces spp. in production of a variety of bioactive compounds, also including anthrabenzoxocinones [33].…”