Antibiotic discovery throughout the Small World Initiative: A molecular strategy to identify biosynthetic gene clusters involved in antagonistic activity

• Published in: MicrobiologyOpen (Weinheim) Vol. 6; no. 3
• Main Authors: Davis, Elizabeth, Sloan, Tyler, Aurelius, Krista, Barbour, Angela, Bodey, Elijah, Clark, Brigette, Dennis, Celeste, Drown, Rachel, Fleming, Megan, Humbert, Allison, Glasgo, Elizabeth, Kerns, Trent, Lingro, Kelly, McMillin, MacKenzie, Meyer, Aaron, Pope, Breanna, Stalevicz, April, Steffen, Brittney, Steindl, Austin, Williams, Carolyn, Wimberley, Carmen, Zenas, Robert, Butela, Kristen, Wildschutte, Hans
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.06.2017; John Wiley and Sons Inc
• Subjects: Anti-Bacterial Agents - biosynthesis; Anti-Bacterial Agents - isolation & purification; Antibiotics; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - isolation & purification; Bacteria - metabolism; biosynthetic gene cluster; Biosynthetic Pathways - genetics; citizen science; Colleges & universities; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; DNA, Ribosomal - chemistry; DNA, Ribosomal - genetics; Drug Discovery - methods; Drug Discovery - organization & administration; Drug resistance; Drugs; Economics; Gene clusters; Gene sequencing; Genomes; Global health; Humans; Listeria; Listeria monocytogenes; Methicillin; Multigene Family; Mutagenesis, Insertional; Original Research; Pathogens; Polymerase chain reaction; Profitability; pseudomonads; RNA, Ribosomal, 16S - genetics; rRNA 16S; Sequence Analysis, DNA; Small World Initiative; Soil bacteria; Soil Microbiology; Soil microorganisms; Staphylococcus infections; Strains (organisms); Students; Transposon mutagenesis; United States; Universities; Workflow; Small World Initiative; citizen science; biosynthetic gene cluster; pseudomonads
• ISSN: 2045-8827; 2045-8827
• DOI: 10.1002/mbo3.435

The emergence of bacterial pathogens resistant to all known antibiotics is a global health crisis. Adding to this problem is that major pharmaceutical companies have shifted away from antibiotic discovery due to low profitability. As a result, the pipeline of new antibiotics is essentially dry and many bacteria now resist the effects of most commonly used drugs. To address this global health concern, citizen science through the Small World Initiative (SWI) was formed in 2012. As part of SWI, students isolate bacteria from their local environments, characterize the strains, and assay for antibiotic production. During the 2015 fall semester at Bowling Green State University, students isolated 77 soil‐derived bacteria and genetically characterized strains using the 16S rRNA gene, identified strains exhibiting antagonistic activity, and performed an expanded SWI workflow using transposon mutagenesis to identify a biosynthetic gene cluster involved in toxigenic compound production. We identified one mutant with loss of antagonistic activity and through subsequent whole‐genome sequencing and linker‐mediated PCR identified a 24.9 kb biosynthetic gene locus likely involved in inhibitory activity in that mutant. Further assessment against human pathogens demonstrated the inhibition of Bacillus cereus, Listeria monocytogenes, and methicillin‐resistant Staphylococcus aureus in the presence of this compound, thus supporting our molecular strategy as an effective research pipeline for SWI antibiotic discovery and genetic characterization. The evolution of bacterial resistance to all known antibiotics is a global crisis. To combat this concern, the Small World Initiative (SWI) was created to crowd source efforts in antibiotic discovery and education. In this report, we expand on the traditional SWI workflow and offer an alternative approach using molecular techniques to identify biosynthetic gene clusters involved in antibiotic production.