{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T14:27:16Z","timestamp":1788532036983,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T00:00:00Z","timestamp":1788480000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: Bacillus spp. are often isolated from airborne microbiota. Five Bacillus strains (AD12\u201316) isolated from dust during a sandstorm in Kuwait were characterized for their potential to produce antimicrobial compounds, biosurfactants and siderophores by genotypic and phenotypic approaches. Methods: Whole-genome sequencing was performed, and biosynthetic gene clusters (BGCs) were predicted using antiSMASH. Antimicrobial activities were determined by agar-well diffusion assays. Siderophore and biosurfactant production were determined by Arnow\u2019s and drop-collapse assays, respectively. The active metabolites were separated, fractionated, and analyzed by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and LC\u2013MS\/MS. Results: Genome mining identified many BGCs associated with known secondary metabolites such as bacillibactin and bacilysin, as well as a number of unassigned clusters. The isolates exhibited distinct antimicrobial profiles, with Bacillus subtilis AD16 displaying the highest antimicrobial activity against multidrug-resistant pathogens. Biosurfactant- and siderophore-associated activities varied among the isolates. Active fractions demonstrated bactericidal activity, while LC\u2013MS\/MS analysis revealed molecular features tentatively assigned to siderophore- and lipopeptide-associated metabolite classes based on accurate mass and MS\/MS fragmentation patterns. Conclusions: The combination of unassigned BGCs, antimicrobial activity, and incompletely characterized molecular features highlights unexplored biosynthetic potential in sandstorm-derived Bacillus. Further purification and structural characterization are required to establish the identities and biological functions of the active metabolites.<\/jats:p>","DOI":"10.3390\/antibiotics15090863","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T13:50:44Z","timestamp":1788529844000},"page":"863","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Genomic and Phenotypic Characterization of Sandstorm-Derived Airborne Bacillus Strains Reveals Diverse Biosynthetic Potential"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-8032-1303","authenticated-orcid":false,"given":"Khadijah M.","family":"Dashti","sequence":"first","affiliation":[{"name":"Department of Medical Laboratory Sciences, Faculty of Allied Health Sciences, Kuwait University, Kuwait City 46300, Kuwait"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-7740-3703","authenticated-orcid":false,"given":"Leila","family":"Vali","sequence":"additional","affiliation":[{"name":"School of Education and Applied Science, Francis Close Hall Campus, University of Gloucestershire, Cheltenham GL50 2RH, UK"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Nawal","family":"Mohammed","sequence":"additional","affiliation":[{"name":"Hematology and Blood Banking Laboratory, Farwaniya Hospital, Farwaniya 81004, Kuwait"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6309-0236","authenticated-orcid":false,"given":"Ali A.","family":"Dashti","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Sciences, Faculty of Allied Health Sciences, Kuwait University, Kuwait City 46300, Kuwait"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1016\/S0140-6736(21)02724-0","article-title":"Global burden of bacterial antimicrobial resistance in 2019: A systematic analysis","volume":"399","author":"Murray","year":"2022","journal-title":"Lancet"},{"key":"ref_2","unstructured":"World Health Organization (2024). 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