Biotechnological potential of Actinobacteria from Canadian and Azorean volcanic caves

• Published in: Applied microbiology and biotechnology 2017-01, Vol.101 (2), p.843-857
• Main Authors: Riquelme, Cristina, Enes Dapkevicius, Maria de Lurdes, Miller, Ana Z., Charlop-Powers, Zachary, Brady, Sean, Mason, Cohord, Cheeptham, Naowarat
• Format: Article
• Language: English
• Subjects: Actinobacteria; Actinomycetes; Analysis; Anti-Bacterial Agents - metabolism; Antibiotics; Antimicrobial agents; Arthrobacter; Arthrobacter - genetics; Arthrobacter - isolation & purification; Arthrobacter - metabolism; Azores; Bacteria; Biodiversity; Biofilms; Biological Products - metabolism; Biomedical and Life Sciences; Biosynthesis; Biotechnology; British Columbia; Caves; Caves - microbiology; Computational Biology; Environmental aspects; Environmental Biotechnology; Enzymatic activity; Enzymes; Enzymes - analysis; Genome, Bacterial; Genomics; Lava; Life Sciences; Limestone; Metabolites; Metagenomics; Microbial Genetics and Genomics; Microbiology; National parks; Natural products; Peptide Biosynthesis, Nucleic Acid-Independent - genetics; Peptides; Scanning electron microscopy; Secondary Metabolism; Secondary metabolites; Sediments; Streptomyces; Streptomyces - genetics; Streptomyces - isolation & purification; Streptomyces - metabolism
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-016-7932-7

Caves are regarded as extreme habitats with appropriate conditions for the development of Actinobacteria. In comparison with other habitats, caves have not yet been the target of intensive screening for bioactive secondary metabolites produced by actinomycetes. As a primary screening strategy, we conducted a metagenomic analysis of the diversity and richness of a key gene required for non-ribosomal peptide (NRP) biosynthesis, focusing on cave-derived sediments from two Canadian caves (a lava tube and a limestone cave) to help us predict whether different types of caves may harbor drug-producing actinobacteria. Using degenerate PCR primers targeting adenylation domains (AD), a conserved domain in the core gene in NRP biosynthesis, a number of amplicons were obtained that mapped back to biomedically relevant NRP gene cluster families. This result guided our culture-dependent sampling strategy of actinomycete isolation from the volcanic caves of Canada (British Columbia) and Portugal (Azores) and subsequent characterization of their antibacterial and enzymatic activities. Multiple enzymatic and antimicrobial activities were identified from bacterial of the Arthrobacter and Streptomyces genera demonstrating that actinomycetes from volcanic caves are promising sources of antibacterial, antibiofilm compounds and industrially relevant enzymes.